API

Python API

controllers

ArticulationController

PD Controller of all degrees of freedom of an articulation, can apply position targets, velocity targets and efforts.

loggers

DataLogger

This class takes care of collecting data as well as reading already saved data in order to replay it for instance.

materials

VisualMaterial	[summary]
PreviewSurface	[summary]
OmniPBR	[summary]
OmniGlass	[summary]
PhysicsMaterial	[summary]
ParticleMaterial	A wrapper around position-based-dynamics (PBD) material for particles used to simulate fluids, cloth and inflatables.
ParticleMaterialView	The view class to deal with particleMaterial prims.
DeformableMaterial	A wrapper around deformable material used to simulate soft bodies.
DeformableMaterialView	The view class to deal with deformableMaterial prims.

objects

GroundPlane	High level wrapper to create/encapsulate a ground plane
VisualCapsule	High level wrapper to create/encapsulate a visual capsule
VisualCone	High level wrapper to create/encapsulate a visual cone
VisualCuboid	High level wrapper to create/encapsulate a visual cuboid
VisualCylinder	High level wrapper to create/encapsulate a visual cylinder
VisualSphere	High level wrapper to create/encapsulate a visual sphere
FixedCapsule	High level wrapper to create/encapsulate a fixed capsule
FixedCone	High level wrapper to create/encapsulate a fixed cone
FixedCuboid	High level wrapper to create/encapsulate a fixed cuboid
FixedCylinder	High level wrapper to create/encapsulate a fixed cylinder
FixedSphere	High level wrapper to create/encapsulate a fixed sphere
DynamicCapsule	High level wrapper to create/encapsulate a dynamic capsule
DynamicCone	High level wrapper to create/encapsulate a dynamic cone
DynamicCuboid	High level wrapper to create/encapsulate a dynamic cuboid
DynamicCylinder	High level wrapper to create/encapsulate a dynamic cylinder
DynamicSphere	High level wrapper to create/encapsulate a dynamic sphere

physics_context

PhysicsContext

Provides high level functions to deal with a physics scene and its settings. This will create a

robots

Robot	Implementation (on SingleArticulation class) to deal with an articulation prim as a robot
RobotView	Implementation (on Articulation class) to deal with articulation prims as robots

scenes

Scene	Provide methods to add objects of interest in the stage to retrieve their information and set their reset default state in an easy way
SceneRegistry	Class to keep track of the different types of objects added to the scene

sensors

BaseSensor	Provides a common properties and methods to deal with prims as a sensor
RigidContactView	Provides high level functions to deal with rigid prims (one or many) that track their contacts through filters as well as their attributes/properties.

simulation_context

SimulationContext

This class provide functions that take care of many time-related events such as perform a physics or a render step for instance.

world

World

This class inherits from SimulationContext which provides the following.

tasks

BaseTask	This class provides a way to set up a task in a scene and modularize adding objects to stage, getting observations needed for the behavioral layer, calculating metrics needed about the task, calling certain things pre-stepping, creating multiple tasks at the same time and much more.
FollowTarget	[summary]
PickPlace	[summary]
Stacking	[summary]

Controllers

class ArticulationController

Bases: object

PD Controller of all degrees of freedom of an articulation, can apply position targets, velocity targets and efforts.

Checkout the required tutorials at

https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

initialize(articulation_view) → None

[summary]

Parameters:

articulation_view ([type]) – [description]

apply_action(

control_actions: ArticulationAction,

) → None

[summary]

Parameters:

• control_actions (ArticulationAction) – actions to be applied for next physics step.

• indices (Optional[Union[list, np.ndarray]], optional) – degree of freedom indices to apply actions to. Defaults to all degrees of freedom.

Raises:

Exception – [description]

set_gains(

kps: ndarray | None = None,

kds: ndarray | None = None,

save_to_usd: bool = False,

) → None

[summary]

Parameters:

• kps (Optional[np.ndarray], optional) – [description]. Defaults to None.

• kds (Optional[np.ndarray], optional) – [description]. Defaults to None.

Raises:

Exception – [description]

get_gains() → Tuple[ndarray, ndarray]

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

Tuple[np.ndarray, np.ndarray]

switch_control_mode(mode: str) → None

[summary]

Parameters:

mode (str) – [description]

Raises:

Exception – [description]

switch_dof_control_mode(

dof_index: int,

mode: str,

) → None

[summary]

Parameters:

• dof_index (int) – [description]

• mode (str) – [description]

Raises:

Exception – [description]

set_max_efforts(

values: ndarray,

joint_indices: ndarray | list | None = None,

) → None

[summary]

Parameters:

• value (float, optional) – [description]. Defaults to None.

• indices (Optional[Union[np.ndarray, list]], optional) – [description]. Defaults to None.

Raises:

Exception – [description]

get_max_efforts() → ndarray

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

np.ndarray

set_effort_modes(

mode: str,

joint_indices: ndarray | list | None = None,

) → None

[summary]

Parameters:

• mode (str) – [description]

• indices (Optional[Union[np.ndarray, list]], optional) – [description]. Defaults to None.

Raises:

• Exception – [description]

• Exception – [description]

get_effort_modes() → List[str]

[summary]

Raises:

• Exception – [description]

• NotImplementedError – [description]

Returns:

[description]

Return type:

np.ndarray

get_joint_limits() → Tuple[ndarray, ndarray]

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

Tuple[np.ndarray, np.ndarray]

get_applied_action() → ArticulationAction

Raises:

Exception – [description]

Returns:

Gets last applied action.

Return type:

ArticulationAction

Loggers

class DataLogger

Bases: object

This class takes care of collecting data as well as reading already saved data in order to replay it for instance.

add_data(

data: dict,

current_time_step: float,

current_time: float,

) → None

Adds data to the log

Parameters:

• data (dict) – Dictionary representing the data to be logged at this time index.

• current_time_step (float) – time step corresponding to the data collected.

• current_time (float) – time in seconds corresponding to the data collected.

get_num_of_data_frames() → int

Returns:

the number of data frames collected/ retrieved in the data logger.

Return type:

int

pause() → None

Pauses data collection.

start() → None

Resumes/ starts data collection.

is_started() → bool

Returns:

True if data collection is started/ resumed. False otherwise.

Return type:

bool

reset() → None

Clears the data in the logger.

get_data_frame(

data_frame_index: int,

) → DataFrame

Parameters:

data_frame_index (int) – index of the data frame to retrieve.

Returns:

Data Frame collected/ retrieved at the specified data frame index.

Return type:

DataFrame

add_data_frame_logging_func(

func: Callable[[List[BaseTask], Scene], Dict],

) → None

Parameters:

func (Callable[[list[BaseTask], Scene], None]) –

function to be called at every step when the logger is started. should follow:

def dummy_data_collection_fn(tasks, scene):

return {“data 1”: [data]}

save(log_path: str) → None

Saves the current data in the logger to a json file

Parameters:

log_path (str) – path of the json file to be used to save the data.

load(log_path: str) → None

Loads data from a json file to read back a previous saved data or to resume recording data from another time step.

Parameters:

log_path (str) – path of the json file to be used to load the data.

Materials

class VisualMaterial(

name: str,

prim_path: str,

prim: pxr.Usd.Prim,

shaders_list: List[pxr.UsdShade.Shader],

material: pxr.UsdShade.Material,

)

Bases: object

[summary]

Parameters:

• name (str) – [description]

• prim_path (str) – [description]

• prim (Usd.Prim) – [description]

• shaders_list (list[UsdShade.Shader]) – [description]

• material (UsdShade.Material) – [description]

property material: pxr.UsdShade.Material

[summary]

Returns:

[description]

Return type:

UsdShade.Material

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns:

[description]

Return type:

[type]

property name: str

[summary]

Returns:

[description]

Return type:

str

property prim_path: str

[summary]

Returns:

[description]

Return type:

str

property prim: pxr.Usd.Prim

[summary]

Returns:

[description]

Return type:

Usd.Prim

class PreviewSurface(

prim_path: str,

name: str = 'preview_surface',

shader: pxr.UsdShade.Shader | None = None,

color: ndarray | None = None,

roughness: float | None = None,

metallic: float | None = None,

)

Bases: VisualMaterial

[summary]

Parameters:

• prim_path (str) – [description]

• name (str, optional) – [description]. Defaults to “preview_surface”.

• shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

• color (Optional[np.ndarray], optional) – [description]. Defaults to None.

• roughness (Optional[float], optional) – [description]. Defaults to None.

• metallic (Optional[float], optional) – [description]. Defaults to None.

set_color(color: ndarray) → None

[summary]

Parameters:

color (np.ndarray) – [description]

get_color() → ndarray

[summary]

Returns:

[description]

Return type:

np.ndarray

set_roughness(roughness: float) → None

[summary]

Parameters:

roughness (float) – [description]

get_roughness() → float

[summary]

Returns:

[description]

Return type:

float

set_metallic(metallic: float) → None

[summary]

Parameters:

metallic (float) – [description]

get_metallic() → float

[summary]

Returns:

[description]

Return type:

float

property material: pxr.UsdShade.Material

[summary]

Returns:

[description]

Return type:

UsdShade.Material

property name: str

[summary]

Returns:

[description]

Return type:

str

property prim: pxr.Usd.Prim

[summary]

Returns:

[description]

Return type:

Usd.Prim

property prim_path: str

[summary]

Returns:

[description]

Return type:

str

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns:

[description]

Return type:

[type]

class OmniPBR(

prim_path: str,

name: str = 'omni_pbr',

shader: pxr.UsdShade.Shader | None = None,

texture_path: str | None = None,

texture_scale: ndarray | None = None,

texture_translate: ndarray | None = None,

color: ndarray | None = None,

)

Bases: VisualMaterial

[summary]

Parameters:

• prim_path (str) – [description]

• name (str, optional) – [description]. Defaults to “omni_pbr”.

• shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

• texture_path (Optional[str], optional) – [description]. Defaults to None.

• texture_scale (Optional[np.ndarray], optional) – [description]. Defaults to None.

• texture_translate (Optional[np.ndarray, optional) – [description]. Defaults to None.

• color (Optional[np.ndarray], optional) – [description]. Defaults to None.

set_color(color: ndarray) → None

[summary]

Parameters:

color (np.ndarray) – [description]

get_color() → ndarray

[summary]

Returns:

[description]

Return type:

np.ndarray

set_texture(path: str) → None

[summary]

Parameters:

path (str) – [description]

get_texture() → str

[summary]

Returns:

[description]

Return type:

str

set_texture_scale(x: float, y: float) → None

[summary]

Parameters:

• x (float) – [description]

• y (float) – [description]

set_texture_translate(x: float, y: float) → None

[summary]

Parameters:

• x (float) – [description]

• y (float) – [description]

get_texture_scale() → ndarray

[summary]

Returns:

[description]

Return type:

np.ndarray

get_texture_translate() → ndarray

[summary]

Returns:

[description]

Return type:

np.ndarray

set_project_uvw(flag: bool) → None

[summary]

Parameters:

flag (bool) – [description]

get_project_uvw() → bool

[summary]

Returns:

[description]

Return type:

bool

set_reflection_roughness(amount: float) → None

[summary]

Parameters:

amount (float) – [description]

get_reflection_roughness() → float

[summary]

Returns:

[description]

Return type:

float

set_metallic_constant(amount: float) → None

[summary]

Parameters:

amount (float) – [description]

get_metallic_constant() → float

[summary]

Returns:

[description]

Return type:

float

property material: pxr.UsdShade.Material

[summary]

Returns:

[description]

Return type:

UsdShade.Material

property name: str

[summary]

Returns:

[description]

Return type:

str

property prim: pxr.Usd.Prim

[summary]

Returns:

[description]

Return type:

Usd.Prim

property prim_path: str

[summary]

Returns:

[description]

Return type:

str

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns:

[description]

Return type:

[type]

class OmniGlass(

prim_path: str,

name: str = 'omni_glass',

shader: pxr.UsdShade.Shader | None = None,

color: ndarray | None = None,

ior: float | None = None,

depth: float | None = None,

thin_walled: bool | None = None,

)

Bases: VisualMaterial

[summary]

Parameters:

• prim_path (str) – [description]

• name (str, optional) – [description]. Defaults to “omni_glass”.

• shader (Optional[UsdShade.Shader], optional) – [description]. Defaults to None.

• color (Optional[np.ndarray], optional) – [description]. Defaults to None.

• ior (Optional[float], optional) – [description]. Defaults to None.

• depth (Optional[float], optional) – [description]. Defaults to None.

• thin_walled (Optional[bool], optional) – [description]. Defaults to None.

Raises:

Exception – [description]

set_color(color: ndarray) → None

[summary]

Parameters:

color (np.ndarray) – [description]

get_color() → ndarray | None

[summary]

Returns:

[description]

Return type:

np.ndarray

set_ior(ior: float) → None

get_ior() → float | None

set_depth(depth: float) → None

get_depth() → float | None

set_thin_walled(thin_walled: float) → None

get_thin_walled() → float | None

property material: pxr.UsdShade.Material

[summary]

Returns:

[description]

Return type:

UsdShade.Material

property name: str

[summary]

Returns:

[description]

Return type:

str

property prim: pxr.Usd.Prim

[summary]

Returns:

[description]

Return type:

Usd.Prim

property prim_path: str

[summary]

Returns:

[description]

Return type:

str

property shaders_list: List[pxr.UsdShade.Shader]

[summary]

Returns:

[description]

Return type:

[type]

class PhysicsMaterial(

prim_path: str,

name: str = 'physics_material',

static_friction: float | None = None,

dynamic_friction: float | None = None,

restitution: float | None = None,

)

Bases: object

[summary]

Parameters:

• prim_path (str) – [description]

• name (str, optional) – [description]. Defaults to “physics_material”.

• static_friction (Optional[float], optional) – [description]. Defaults to None.

• dynamic_friction (Optional[float], optional) – [description]. Defaults to None.

• restitution (Optional[float], optional) – [description]. Defaults to None.

property prim_path: str

[summary]

Returns:

[description]

Return type:

str

property prim: pxr.Usd.Prim

[summary]

Returns:

[description]

Return type:

Usd.Prim

property name: str

[summary]

Returns:

[description]

Return type:

str

property material: pxr.UsdShade.Material

[summary]

Returns:

[description]

Return type:

UsdShade.Material

set_dynamic_friction(friction: float) → None

[summary]

Parameters:

friction (float) – [description]

get_dynamic_friction() → float

[summary]

Returns:

[description]

Return type:

float

set_static_friction(friction: float) → None

[summary]

Parameters:

friction (float) – [description]

get_static_friction() → float

[summary]

Returns:

[description]

Return type:

float

set_restitution(restitution: float) → None

[summary]

Parameters:

restitution (float) – [description]

get_restitution() → float

[summary]

Returns:

[description]

Return type:

float

class ParticleMaterial(

prim_path: str,

name: str | None = 'particle_material',

friction: float | None = None,

particle_friction_scale: float | None = None,

damping: float | None = None,

viscosity: float | None = None,

vorticity_confinement: float | None = None,

surface_tension: float | None = None,

cohesion: float | None = None,

adhesion: float | None = None,

particle_adhesion_scale: float | None = None,

adhesion_offset_scale: float | None = None,

gravity_scale: float | None = None,

lift: float | None = None,

drag: float | None = None,

)

Bases: object

A wrapper around position-based-dynamics (PBD) material for particles used to simulate fluids, cloth and inflatables.

Note

Currently, only a single material per particle system is supported which applies to all objects that are associated with the system.

property prim_path: str

Returns: str: The stage path to the material.

property prim: pxr.Usd.Prim

Returns: Usd.Prim: The USD prim present.

property material: pxr.UsdShade.Material

Returns: UsdShade.Material: The USD Material object.

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

initialize(physics_sim_view=None) → None

is_valid() → bool

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

post_reset() → None

Resets the prim to its default state.

set_friction(value: float) → None

Sets the friction coefficient.

The friction takes effect in all interactions between particles and rigids or deformables. For solid particle-particle interactions it is multiplied by the particle friction scale.

Parameters:

value (float) – The friction coefficient. Range: [0, inf), Units: dimensionless

set_particle_friction_scale(value: float) → None

Sets the particle friction scale.

The coefficient that scales friction for solid particle-particle interaction.

Parameters:

value (float) – The particle friction scale. Range: [0, inf), Units: dimensionless

set_damping(value: float) → None

Sets the global velocity damping coefficient.

Parameters:

value (float) – The damping coefficient. Range: [0, inf), Units: dimensionless

set_viscosity(value: float) → None

Sets the viscosity for fluid particles.

Parameters:

value (float) – The viscosity. Range: [0, inf), Units: dimensionless

set_vorticity_confinement(value: float) → None

Sets the vorticity confinement for fluid particles.

This helps prevent energy loss due to numerical solver by adding vortex-like accelerations to the particles.

Parameters:

value (float) – The vorticity confinement. Range: [0, inf), Units: dimensionless

set_surface_tension(value: float) → None

Sets the surface tension for fluid particles.

Parameters:

value (float) – The surface tension. Range: [0, inf), Units: 1 / (distance * distance * distance)

set_cohesion(value: float) → None

Sets the cohesion for interaction between fluid particles.

Parameters:

value (float) – The cohesion. Range: [0, inf), Units: dimensionless

set_adhesion(value: float) → None

Sets the adhesion for interaction between particles (solid or fluid), and rigid or deformable objects.

Note

Adhesion also applies to solid-solid particle interactions, but is multiplied with the particle adhesion scale.

Parameters:

value (float) – The adhesion. Range: [0, inf), Units: dimensionless

set_particle_adhesion_scale(value: float) → None

Sets the particle adhesion scale.

This coefficient scales the adhesion for solid particle-particle interaction.

Parameters:

value (float) – The adhesion scale. Range: [0, inf), Units: dimensionless

set_adhesion_offset_scale(value: float) → None

Sets the adhesion offset scale.

It defines the offset at which adhesion ceases to take effect. For interactions between particles (fluid or solid), and rigids or deformables, the adhesion offset is defined relative to the rest offset. For solid particle-particle interactions, the adhesion offset is defined relative to the solid rest offset.

Parameters:

value (float) – The adhesion offset scale. Range: [0, inf), Units: dimensionless

set_gravity_scale(value: float) → None

Sets the gravitational acceleration scaling factor.

It can be used to approximate lighter-than-air inflatable. For example (-1.0 would invert gravity).

Parameters:

value (float) – The gravity scale. Range: (-inf , inf), Units: dimensionless

set_lift(value: float) → None

Sets the lift coefficient, i.e. basic aerodynamic lift model coefficient.

It is useful for cloth and inflatable particle objects.

Parameters:

value (float) – The lift coefficient. Range: [0, inf), Units: dimensionless

set_drag(value: float) → None

Sets the drag coefficient, i.e. basic aerodynamic drag model coefficient.

It is useful for cloth and inflatable particle objects.

Parameters:

value (float) – The drag coefficient. Range: [0, inf), Units: dimensionless

get_friction() → float

Returns:

The friction coefficient.

Return type:

float

get_particle_friction_scale() → float

Returns:

The particle friction scale.

Return type:

float

get_damping() → float

Returns:

The global velocity damping coefficient.

Return type:

float

get_viscosity() → float

Returns:

The viscosity.

Return type:

float

get_vorticity_confinement() → float

Returns:

The vorticity confinement for fluid particles.

Return type:

float

get_surface_tension() → float

Returns:

The surface tension for fluid particles.

Return type:

float

get_cohesion() → float

Returns:

The cohesion for interaction between fluid particles.

Return type:

float

get_adhesion() → float

Returns:

The adhesion for interaction between particles (solid or fluid), and rigids or deformables.

Return type:

float

get_particle_adhesion_scale() → float

Returns:

The particle adhesion scale.

Return type:

float

get_adhesion_offset_scale() → float

Returns:

The adhesion offset scale.

Return type:

float

get_gravity_scale() → float

Returns:

The gravitational acceleration scaling factor.

Return type:

float

get_lift() → float

Returns:

The lift coefficient, basic aerodynamic lift model coefficient.

Return type:

float

get_drag() → float

Returns:

The drag coefficient, basic aerodynamic drag model coefficient.

Return type:

float

class ParticleMaterialView(

prim_paths_expr: str,

name: str = 'particle_material_view',

frictions: ndarray | Tensor | None = None,

particle_friction_scales: ndarray | Tensor | None = None,

dampings: ndarray | Tensor | None = None,

viscosities: ndarray | Tensor | None = None,

vorticity_confinements: ndarray | Tensor | None = None,

surface_tensions: ndarray | Tensor | None = None,

cohesions: ndarray | Tensor | None = None,

adhesions: ndarray | Tensor | None = None,

particle_adhesion_scales: ndarray | Tensor | None = None,

adhesion_offset_scales: ndarray | Tensor | None = None,

gravity_scales: ndarray | Tensor | None = None,

lifts: ndarray | Tensor | None = None,

drags: ndarray | Tensor | None = None,

)

Bases: object

The view class to deal with particleMaterial prims. Provides high level functions to deal with particle material (1 or more particle materials) as well as its attributes/ properties. This object wraps all matching materials found at the regex provided at the prim_paths_expr. This object wraps all matching materials Prims found at the regex provided at the prim_paths_expr.

property count: int

Returns: int: number of rigid shapes for the prims in the view.

property name: str

Returns: str: name given to the view when instantiating it.

is_physics_handle_valid() → bool

Returns:

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type:

bool

is_valid(

indices: ndarray | list | Tensor | None = None,

) → bool

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type:

bool

post_reset() → None

Resets the particles to their initial states.

initialize(

physics_sim_view: omni.physics.tensors.SimulationView | None = None,

) → None

Create a physics simulation view if not passed and creates a rigid body view in physX.

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

set_frictions(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the friction for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material friction tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_frictions(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the friction of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

friction tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_dampings(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the dampings for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_dampings(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the dampings of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

dampings tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_gravity_scales(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the gravity scale for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material gravity scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_gravity_scales(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the gravity scale of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

gravity scale tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_lifts(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the lifts for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material lift tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_lifts(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the lifts of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

lift tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_drags(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the drags for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material drag tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_drags(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the drags of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

drag tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_viscosities(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle viscosity for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle viscosity scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_viscosities(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the viscosity of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

viscosity tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_cohesions(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle cohesion for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle cohesion scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_cohesions(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the cohesion of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

cohesion tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_adhesions(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle adhesion for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle adhesion scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_adhesions(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the adhesion of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

adhesion tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_particle_adhesion_scales(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle adhesion for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle adhesion scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_particle_adhesion_scales(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the adhesion scale of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

adhesion scale tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_adhesion_offset_scales(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the adhesion offset scale for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material adhesion offset scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_adhesion_offset_scales(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the adhesion offset scale of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

adhesion offset scale tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_surface_tensions(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle surface tension for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle surface tension scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_surface_tensions(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the surface tension of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

surface tension tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_vorticity_confinements(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the vorticity confinement for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle vorticity confinement scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_vorticity_confinements(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the vorticity confinement of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

vorticity confinement tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_particle_friction_scales(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the particle friction scale for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material particle friction scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_particle_friction_scales(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the particle friction scale of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

particle friction scale tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

class DeformableMaterial(

prim_path: str,

name: str | None = 'deformable_material',

dynamic_friction: float | None = None,

youngs_modulus: float | None = None,

poissons_ratio: float | None = None,

elasticity_damping: float | None = None,

damping_scale: float | None = None,

)

Bases: object

A wrapper around deformable material used to simulate soft bodies.

property prim_path: str

Returns: str: The stage path to the material.

property prim: pxr.Usd.Prim

Returns: Usd.Prim: The USD prim present.

property material: pxr.UsdShade.Material

Returns: UsdShade.Material: The USD Material object.

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

initialize(physics_sim_view=None) → None

is_valid() → bool

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

post_reset() → None

Resets the prim to its default state.

set_dynamic_friction(value: float) → None

Sets the dynamic_friction coefficient.

The dynamic_friction takes effect in all interactions between particles and rigids or deformables. For solid particle-particle interactions it is multiplied by the particle dynamic_friction scale.

Parameters:

value (float) – The dynamic_friction coefficient. Range: [0, inf), Units: dimensionless

set_youngs_modululs(value: float) → None

Sets the youngs_modululs for fluid particles.

Parameters:

value (float) – The youngs_modululs. Range: [0, inf)

set_poissons_ratio(value: float) → None

Sets the poissons ratio coefficient

Parameters:

value (float) – The poissons ratio. Range: (0 , 0.5)

set_damping_scale(value: float) → None

Sets the damping scale coefficient.

Parameters:

value (float) – The damping scale coefficient Range: [0, inf)

set_elasticity_damping(value: float) → None

Sets the global velocity elasticity damping coefficient.

Parameters:

value (float) – The elasticity damping coefficient. Range: [0, inf), Units: dimensionless

get_dynamic_friction() → float

Returns:

The dynamic friction coefficient.

Return type:

float

get_youngs_modululs() → float

Returns:

The youngs modululs coefficient.

Return type:

float

get_poissons_ratio() → float

Returns:

The poissons ratio.

Return type:

float

get_damping_scale() → float

Returns:

The damping scale coefficient.

Return type:

float

get_elasticity_damping() → float

Returns:

The elasticity damping coefficient.

Return type:

float

class DeformableMaterialView(

prim_paths_expr: str,

name: str = 'deformable_material_view',

dynamic_frictions: ndarray | Tensor | None = None,

youngs_moduli: ndarray | Tensor | None = None,

poissons_ratios: ndarray | Tensor | None = None,

elasticity_dampings: ndarray | Tensor | None = None,

damping_scales: ndarray | Tensor | None = None,

)

Bases: object

The view class to deal with deformableMaterial prims. Provides high level functions to deal with deformable material (1 or more deformable materials) as well as its attributes/ properties. This object wraps all matching materials found at the regex provided at the prim_paths_expr. This object wraps all matching materials Prims found at the regex provided at the prim_paths_expr.

property count: int

Returns: int: number of rigid shapes for the prims in the view.

property name: str

Returns: str: name given to the view when instantiating it.

is_physics_handle_valid() → bool

Returns:

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type:

bool

is_valid(

indices: ndarray | list | Tensor | None = None,

) → bool

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type:

bool

post_reset() → None

Resets the deformables to their initial states.

initialize(

physics_sim_view: omni.physics.tensors.SimulationView | None = None,

) → None

Create a physics simulation view if not passed and creates a rigid body view in physX.

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

set_dynamic_frictions(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the dynamic friction for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material dynamic friction tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_dynamic_frictions(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the dynamic friction of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

dynamic friction tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_elasticity_dampings(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the elasticity_dampings for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_elasticity_dampings(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the elasticity dampings of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

elasticity dampings tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_damping_scales(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the damping scale for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material damping scale tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_damping_scales(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the damping scale of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

damping scale tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_poissons_ratios(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the poissons ratios for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material poissons ratio tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_poissons_ratios(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the poissons ratios of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

poissons ratio tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

set_youngs_moduli(

values: ndarray | Tensor | None,

indices: ndarray | list | Tensor | None = None,

) → None

Sets the youngs moduli for the material prims indicated by the indices.

Parameters:

• values (Optional[Union[np.ndarray, torch.Tensor]], optional) – material drag tensor with the shape (M, ).

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

get_youngs_moduli(

indices: ndarray | list | Tensor | None = None,

clone: bool = True,

) → ndarray | Tensor

Gets the Youngs moduli of materials indicated by the indices.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor]], optional) – indices to specify which material prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

Youngs moduli tensor with shape (M, )

Return type:

Union[np.ndarray, torch.Tensor]

Objects

Modules to create/encapsulate visual, fixed, and dynamic shapes (Capsule, Cone, Cuboid, Cylinder, Sphere) as well as ground planes

Type	Collider API	Rigid Body API
Visual	No	No
Fixed	Yes	No
Dynamic	Yes	Yes

class GroundPlane(

prim_path: str,

name: str = 'ground_plane',

size: float | None = None,

z_position: float | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

physics_material: PhysicsMaterial | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: object

High level wrapper to create/encapsulate a ground plane

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “ground_plane”.

• size (Optional[float], optional) – length of each edge. Defaults to 5000.0.

• z_position (float, optional) – ground plane position in the z-axis. Defaults to 0.

• scale (Optional[np.ndarray], optional) – local scale to be applied to the prim’s dimensions. Defaults to None.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual plane. Defaults to None.

• physics_material_path (Optional[PhysicsMaterial], optional) – path of the physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• static_friction (float, optional) – static friction coefficient. Defaults to 0.5.

• dynamic_friction (float, optional) – dynamic friction coefficient. Defaults to 0.5.

• restitution (float, optional) – restitution coefficient. Defaults to 0.8.

Example:

>>> from isaacsim.core.api.objects import GroundPlane
>>> import numpy as np
>>>
>>> # create a ground plane placed at 0 in the z-axis
>>> plane = GroundPlane(prim_path="/World/GroundPlane", z_position=0)
>>> plane
<isaacsim.core.api.objects.ground_plane.GroundPlane object at 0x7f15d003fb50>

property prim_path: str

Returns:

prim path in the stage.

Return type:

str

Example:

>>> plane.prim_path
/World/GroundPlane

property name: str | None

Returns:

name given to the prim when instantiating it. Otherwise None.

Return type:

str

Example:

>>> plane.name
ground_plane

property prim: pxr.Usd.Prim

Returns:

USD Prim object that this object holds.

Return type:

Usd.Prim

Example:

>>> plane.prim
Usd.Prim(</World/GroundPlane>)

property xform_prim: SingleXFormPrim

Returns:

wrapped object as a SingleXFormPrim

Return type:

SingleXFormPrim

Example:

>>> plane.xform_prim
<isaacsim.core.prims.single_xform_prim.SingleXFormPrim object at 0x7f1578d32560>

property collision_geometry_prim: SingleGeometryPrim

Returns:

wrapped object as a SingleGeometryPrim

Return type:

SingleGeometryPrim

Example:

>>> plane.collision_geometry_prim
<isaacsim.core.prims.single_geometry_prim.SingleGeometryPrim object at 0x7f15ff3461a0>

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> plane.initialize()

post_reset() → None

Reset the prim to its default state (position and orientation).

Example:

>>> plane.post_reset()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> plane.is_valid()
True

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> plane.apply_physics_material(material)

get_applied_physics_material() → PhysicsMaterial

Returns the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> plane.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7f517ff62920>

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> plane.set_world_pose(position=np.array([0.0, 0.0, 0.5]), orientation=np.array([1., 0., 0., 0.]))

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (0.0, 0.0, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[0. 0. 0.]
>>> orientation
[1. 0. 0. 0.]

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = plane.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f6efff41cf0>
>>>
>>> state.position
[0. 0. 0.]
>>> state.orientation
[1. 0. 0. 0.]

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Sets the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> plane.set_default_state(position=np.array([0.0, 0.0, -1.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> plane.post_reset()

class VisualCapsule(

prim_path: str,

name: str = 'visual_capsule',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: float | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: SingleGeometryPrim

High level wrapper to create/encapsulate a visual capsule

Note

Visual capsules (Capsule shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_capsule”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – capsule radius. Defaults to None.

• height (Optional[float], optional) – capsule height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from isaacsim.core.api.objects import VisualCapsule
>>> import numpy as np
>>>
>>> # create a red visual capsule at the given path
... prim = VisualCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<isaacsim.core.api.objects.capsule.VisualCapsule object at 0x7f4ff958b0d0>

set_radius(radius: float) → None

Set the capsule radius

Parameters:

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)

get_radius() → float

Get the capsule radius

Returns:

capsule radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

set_height(height: float) → None

Set the capsule height

Parameters:

height (float) – capsule height

Example:

>>> prim.set_height(2.0)

get_height() → float

Get the capsule height

Returns:

capsule height

Return type:

float

Example:

>>> prim.get_height()
1.0

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class VisualCone(

prim_path: str,

name: str = 'visual_cone',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: float | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: SingleGeometryPrim

High level wrapper to create/encapsulate a visual cone

Note

Visual cones (Cone shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cone”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cone height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from isaacsim.core.api.objects import VisualCone
>>> import numpy as np
>>>
>>> # create a red visual cone at the given path
>>> prim = VisualCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<isaacsim.core.api.objects.cone.VisualCone object at 0x7f513413aa70>

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

set_height(height: float) → None

Set the cone height

Parameters:

height (float) – cone height

Example:

>>> prim.set_height(2.0)

get_height() → float

Get the cone height

Returns:

cone height

Return type:

float

Example:

>>> prim.get_height()
1.0

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class VisualCuboid(

prim_path: str,

name: str = 'visual_cube',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = None,

color: ndarray | None = None,

size: float | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: SingleGeometryPrim

High level wrapper to create/encapsulate a visual cuboid

Note

Visual cuboids (Cube shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cube”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• size (Optional[float], optional) – length of each cube edge. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from isaacsim.core.api.objects import VisualCuboid
>>> import numpy as np
>>>
>>> # create a red visual cube at the given path
>>> prim = VisualCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<isaacsim.core.api.objects.cuboid.VisualCuboid object at 0x7f12e756fa00>

set_size(size: float) → None

Set the length of each cube edge

Parameters:

size (float) – edge length

Example:

>>> prim.set_size(2.0)

get_size() → ndarray

Get the length of each cube edge

Returns:

edge length

Return type:

float

Example:

>>> prim.get_size()
1.0

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class VisualCylinder(

prim_path: str,

name: str = 'visual_cylinder',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: float | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: SingleGeometryPrim

High level wrapper to create/encapsulate a visual cylinder

Note

Visual cylinders (Cylinder shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_cylinder”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cylinder height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from isaacsim.core.api.objects import VisualCylinder
>>> import numpy as np
>>>
>>> # create a red visual cylinder at the given path
>>> prim = VisualCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<isaacsim.core.api.objects.cylinder.VisualCylinder object at 0x7f4e433f22c0>

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

set_height(height: float) → None

Set the cylinder height

Parameters:

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)

get_height() → float

Get the cylinder height

Returns:

cylinder height

Return type:

float

Example:

>>> prim.get_height()
1.0

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class VisualSphere(

prim_path: str,

name: str = 'visual_sphere',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = True,

color: ndarray | None = None,

radius: float | None = None,

visual_material: VisualMaterial | None = None,

)

Bases: SingleGeometryPrim

High level wrapper to create/encapsulate a visual sphere

Note

Visual spheres (Sphere shape) have no collisions (Collider API) or rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “visual_sphere”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – sphere radius. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

Example:

>>> from isaacsim.core.api.objects import VisualSphere
>>> import numpy as np
>>>
>>> # create a red visual sphere at the given path
>>> prim = VisualSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<isaacsim.core.api.objects.sphere.VisualSphere object at 0x7f4e3eb3ea70>

set_radius(radius: float) → None

Set the sphere radius

Parameters:

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)

get_radius() → float

Get the sphere radius

Returns:

sphere radius

Return type:

float

Example:

>>> prim.get_radius()
1.0

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class FixedCapsule(

prim_path: str,

name: str = 'fixed_capsule',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

)

Bases: VisualCapsule

High level wrapper to create/encapsulate a fixed capsule

Note

Fixed capsules (Capsule shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_capsule”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – capsule radius. Defaults to None.

• height (Optional[float], optional) – capsule height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from isaacsim.core.api.objects import FixedCapsule
>>> import numpy as np
>>>
>>> # create a red fixed capsule at the given path
>>> prim = FixedCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> print(prim)
<isaacsim.core.api.objects.capsule.FixedCapsule object at 0x7f520c0d4790>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the capsule height

Returns:

capsule height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the capsule radius

Returns:

capsule radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_height(height: float) → None

Set the capsule height

Parameters:

height (float) – capsule height

Example:

>>> prim.set_height(2.0)

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the capsule radius

Parameters:

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class FixedCone(

prim_path: str,

name: str = 'fixed_cone',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

)

Bases: VisualCone

High level wrapper to create/encapsulate a fixed cone

Note

Fixed cones (Cone shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cone”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cone height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from isaacsim.core.api.objects import FixedCone
>>> import numpy as np
>>>
>>> # create a red fixed cone at the given path
>>> prim = FixedCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> prim
<isaacsim.core.api.objects.cone.FixedCone object at 0x7f51489f09a0>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the cone height

Returns:

cone height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(approximation_type: str) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_height(height: float) → None

Set the cone height

Parameters:

height (float) – cone height

Example:

>>> prim.set_height(2.0)

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class FixedCuboid(

prim_path: str,

name: str = 'fixed_cube',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

size: float | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

)

Bases: VisualCuboid

High level wrapper to create/encapsulate a fixed cuboid

Note

Fixed cuboids (Cube shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cube”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• size (Optional[float], optional) – length of each cube edge. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from isaacsim.core.api.objects import FixedCuboid
>>> import numpy as np
>>>
>>> # create a red fixed cube at the given path
>>> prim = FixedCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<isaacsim.core.api.objects.cuboid.FixedCuboid object at 0x7f7b4d91da80>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_size() → ndarray

Get the length of each cube edge

Returns:

edge length

Return type:

float

Example:

>>> prim.get_size()
1.0

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_size(size: float) → None

Set the length of each cube edge

Parameters:

size (float) – edge length

Example:

>>> prim.set_size(2.0)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class FixedCylinder(

prim_path: str,

name: str = 'fixed_cylinder',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: float | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

)

Bases: VisualCylinder

High level wrapper to create/encapsulate a fixed cylinder

Note

Fixed cylinders (Cylinder shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cylinder”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cylinder height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from isaacsim.core.api.objects import FixedCylinder
>>> import numpy as np
>>>
>>> # create a red fixed cylinder at the given path
>>> prim = FixedCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0])
... )
>>> print(prim)
<isaacsim.core.api.objects.cylinder.FixedCylinder object at 0x7f4f24144f40>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the cylinder height

Returns:

cylinder height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_height(height: float) → None

Set the cylinder height

Parameters:

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class FixedSphere(

prim_path: str,

name: str = 'fixed_sphere',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

)

Bases: VisualSphere

High level wrapper to create/encapsulate a fixed sphere

Note

Fixed spheres (Sphere shape) have collisions (Collider API) but no rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_sphere”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – sphere radius. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

Example:

>>> from isaacsim.core.api.objects import FixedSphere
>>> import numpy as np
>>>
>>> # create a red fixed sphere at the given path
>>> prim = FixedSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]))
>>> prim
<isaacsim.core.api.objects.sphere.FixedSphere object at 0x7f4e433f2140>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the sphere radius

Returns:

sphere radius

Return type:

float

Example:

>>> prim.get_radius()
1.0

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the sphere radius

Parameters:

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class DynamicCapsule(

prim_path: str,

name: str = 'dynamic_capsule',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: ndarray | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

mass: float | None = None,

density: float | None = None,

linear_velocity: Sequence[float] | None = None,

angular_velocity: Sequence[float] | None = None,

)

Bases: SingleRigidPrim, FixedCapsule

High level wrapper to create/encapsulate a dynamic capsule

Note

Dynamic capsules (Capsule shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_capsule”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – capsule radius. Defaults to None.

• height (Optional[float], optional) – capsule height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• mass (Optional[float], optional) – mass in kg. Defaults to None.

• density (Optional[float], optional) – density. Defaults to None.

• linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

• angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from isaacsim.core.api.objects import DynamicCapsule
>>> import numpy as np
>>>
>>> # create a red fixed capsule of mass 1kg at the given path
>>> prim = DynamicCapsule(
...     prim_path="/World/Xform/Capsule",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<isaacsim.core.api.objects.capsule.DynamicCapsule object at 0x7f4ff915f8e0>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_rigid_body_physics() → None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()

enable_rigid_body_physics() → None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns:

current angular velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_com() → float

Get the center of mass pose of the rigid body

Returns:

position of the center of mass of the rigid body. np.ndarray: orientation of the center of mass of the rigid body.

Return type:

np.ndarray

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_current_dynamic_state() → DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns:

the dynamic state of the rigid body prim

Return type:

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]

get_default_state() → DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns:

returns the default state of the prim that is used after each reset

Return type:

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]

get_density() → float

Get the density of the rigid body

Returns:

density of the rigid body.

Return type:

float

Example:

>>> prim.get_density()
0

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the capsule height

Returns:

capsule height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_linear_velocity() → ndarray

Get the linear velocity of the rigid body

Returns:

current linear velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_mass() → float

Get the mass of the rigid body

Returns:

mass of the rigid body in kg.

Return type:

float

Example:

>>> prim.get_mass()
0

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the capsule radius

Returns:

capsule radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_sleep_threshold() → float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns:

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type:

float

Example:

>>> prim.get_sleep_threshold()
5e-05

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_com(

position: ndarray,

orientation: ndarray,

) → None

Set the center of mass pose of the rigid body

Parameters:

• position (np.ndarray) – center of mass position. Shape (3,).

• orientation (np.ndarray) – center of mass orientation. Shape (4,).

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

linear_velocity: ndarray | None = None,

angular_velocity: ndarray | None = None,

) → None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

• angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()

set_density(density: float) → None

Set the density of the rigid body

Parameters:

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)

set_height(height: float) → None

Set the capsule height

Parameters:

height (float) – capsule height

Example:

>>> prim.set_height(2.0)

set_linear_velocity(velocity: ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters:

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_mass(mass: float) → None

Set the mass of the rigid body

Parameters:

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the capsule radius

Parameters:

radius (float) – capsule radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_sleep_threshold(threshold: float) → None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters:

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class DynamicCone(

prim_path: str,

name: str = 'dynamic_cone',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: ndarray | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

mass: float | None = None,

density: float | None = None,

linear_velocity: Sequence[float] | None = None,

angular_velocity: Sequence[float] | None = None,

)

Bases: SingleRigidPrim, FixedCone

High level wrapper to create/encapsulate a dynamic cone

Note

Dynamic cones (Cone shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_cone”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cone height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• mass (Optional[float], optional) – mass in kg. Defaults to None.

• density (Optional[float], optional) – density. Defaults to None.

• linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

• angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from isaacsim.core.api.objects import DynamicCone
>>> import numpy as np
>>>
>>> # create a red dynamic cone of mass 1kg at the given path
>>> prim = DynamicCone(
...     prim_path="/World/Xform/Cone",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<isaacsim.core.api.objects.cone.DynamicCone object at 0x7f4f9f5d11b0>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_rigid_body_physics() → None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()

enable_rigid_body_physics() → None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns:

current angular velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_com() → float

Get the center of mass pose of the rigid body

Returns:

position of the center of mass of the rigid body. np.ndarray: orientation of the center of mass of the rigid body.

Return type:

np.ndarray

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_current_dynamic_state() → DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns:

the dynamic state of the rigid body prim

Return type:

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]

get_default_state() → DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns:

returns the default state of the prim that is used after each reset

Return type:

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]

get_density() → float

Get the density of the rigid body

Returns:

density of the rigid body.

Return type:

float

Example:

>>> prim.get_density()
0

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the cone height

Returns:

cone height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_linear_velocity() → ndarray

Get the linear velocity of the rigid body

Returns:

current linear velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_mass() → float

Get the mass of the rigid body

Returns:

mass of the rigid body in kg.

Return type:

float

Example:

>>> prim.get_mass()
0

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_sleep_threshold() → float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns:

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type:

float

Example:

>>> prim.get_sleep_threshold()
5e-05

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_com(

position: ndarray,

orientation: ndarray,

) → None

Set the center of mass pose of the rigid body

Parameters:

• position (np.ndarray) – center of mass position. Shape (3,).

• orientation (np.ndarray) – center of mass orientation. Shape (4,).

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

linear_velocity: ndarray | None = None,

angular_velocity: ndarray | None = None,

) → None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

• angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()

set_density(density: float) → None

Set the density of the rigid body

Parameters:

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)

set_height(height: float) → None

Set the cone height

Parameters:

height (float) – cone height

Example:

>>> prim.set_height(2.0)

set_linear_velocity(velocity: ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters:

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_mass(mass: float) → None

Set the mass of the rigid body

Parameters:

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_sleep_threshold(threshold: float) → None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters:

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class DynamicCuboid(

prim_path: str,

name: str = 'dynamic_cube',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

size: float | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

mass: float | None = None,

density: float | None = None,

linear_velocity: Sequence[float] | None = None,

angular_velocity: Sequence[float] | None = None,

)

Bases: SingleRigidPrim, FixedCuboid

High level wrapper to create/encapsulate a dynamic cuboid

Note

Dynamic cuboids (Cube shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “fixed_cube”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• size (Optional[float], optional) – length of each cube edge. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• mass (Optional[float], optional) – mass in kg. Defaults to None.

• density (Optional[float], optional) – density. Defaults to None.

• linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

• angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from isaacsim.core.api.objects import DynamicCuboid
>>> import numpy as np
>>>
>>> # create a red dynamic cube of mass 1kg at the given path
>>> prim = DynamicCuboid(prim_path="/World/Xform/Cube", color=np.array([1.0, 0.0, 0.0]), mass=1.0)
>>> prim
<isaacsim.core.api.objects.cuboid.DynamicCuboid object at 0x7ff14c04d990>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_rigid_body_physics() → None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()

enable_rigid_body_physics() → None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns:

current angular velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_com() → float

Get the center of mass pose of the rigid body

Returns:

position of the center of mass of the rigid body. np.ndarray: orientation of the center of mass of the rigid body.

Return type:

np.ndarray

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_current_dynamic_state() → DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns:

the dynamic state of the rigid body prim

Return type:

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]

get_default_state() → DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns:

returns the default state of the prim that is used after each reset

Return type:

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]

get_density() → float

Get the density of the rigid body

Returns:

density of the rigid body.

Return type:

float

Example:

>>> prim.get_density()
0

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_linear_velocity() → ndarray

Get the linear velocity of the rigid body

Returns:

current linear velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_mass() → float

Get the mass of the rigid body

Returns:

mass of the rigid body in kg.

Return type:

float

Example:

>>> prim.get_mass()
0

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_size() → ndarray

Get the length of each cube edge

Returns:

edge length

Return type:

float

Example:

>>> prim.get_size()
1.0

get_sleep_threshold() → float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns:

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type:

float

Example:

>>> prim.get_sleep_threshold()
5e-05

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_com(

position: ndarray,

orientation: ndarray,

) → None

Set the center of mass pose of the rigid body

Parameters:

• position (np.ndarray) – center of mass position. Shape (3,).

• orientation (np.ndarray) – center of mass orientation. Shape (4,).

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

linear_velocity: ndarray | None = None,

angular_velocity: ndarray | None = None,

) → None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

• angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()

set_density(density: float) → None

Set the density of the rigid body

Parameters:

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)

set_linear_velocity(velocity: ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters:

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_mass(mass: float) → None

Set the mass of the rigid body

Parameters:

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_size(size: float) → None

Set the length of each cube edge

Parameters:

size (float) – edge length

Example:

>>> prim.set_size(2.0)

set_sleep_threshold(threshold: float) → None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters:

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class DynamicCylinder(

prim_path: str,

name: str = 'dynamic_cylinder',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

height: ndarray | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

mass: float | None = None,

density: float | None = None,

linear_velocity: Sequence[float] | None = None,

angular_velocity: Sequence[float] | None = None,

)

Bases: SingleRigidPrim, FixedCylinder

High level wrapper to create/encapsulate a dynamic cylinder

Note

Dynamic cylinders (Cylinder shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_cylinder”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – base radius. Defaults to None.

• height (Optional[float], optional) – cylinder height. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• mass (Optional[float], optional) – mass in kg. Defaults to None.

• density (Optional[float], optional) – density. Defaults to None.

• linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

• angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from isaacsim.core.api.objects import DynamicCylinder
>>> import numpy as np
>>>
>>> # create a red fixed cylinder of mass 1kg at the given path
>>> prim = DynamicCylinder(
...     prim_path="/World/Xform/Cylinder",
...     radius=0.5,
...     height=1.0,
...     color=np.array([1.0, 0.0, 0.0]),
...     mass=1.0
... )
>>> prim
<isaacsim.core.api.objects.cylinder.DynamicCylinder object at 0x7f4e8f5c4a60>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_rigid_body_physics() → None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()

enable_rigid_body_physics() → None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns:

current angular velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_com() → float

Get the center of mass pose of the rigid body

Returns:

position of the center of mass of the rigid body. np.ndarray: orientation of the center of mass of the rigid body.

Return type:

np.ndarray

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_current_dynamic_state() → DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns:

the dynamic state of the rigid body prim

Return type:

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]

get_default_state() → DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns:

returns the default state of the prim that is used after each reset

Return type:

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]

get_density() → float

Get the density of the rigid body

Returns:

density of the rigid body.

Return type:

float

Example:

>>> prim.get_density()
0

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_height() → float

Get the cylinder height

Returns:

cylinder height

Return type:

float

Example:

>>> prim.get_height()
1.0

get_linear_velocity() → ndarray

Get the linear velocity of the rigid body

Returns:

current linear velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_mass() → float

Get the mass of the rigid body

Returns:

mass of the rigid body in kg.

Return type:

float

Example:

>>> prim.get_mass()
0

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the base radius

Returns:

base radius

Return type:

float

Example:

>>> prim.get_radius()
0.5

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_sleep_threshold() → float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns:

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type:

float

Example:

>>> prim.get_sleep_threshold()
5e-05

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_com(

position: ndarray,

orientation: ndarray,

) → None

Set the center of mass pose of the rigid body

Parameters:

• position (np.ndarray) – center of mass position. Shape (3,).

• orientation (np.ndarray) – center of mass orientation. Shape (4,).

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

linear_velocity: ndarray | None = None,

angular_velocity: ndarray | None = None,

) → None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

• angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()

set_density(density: float) → None

Set the density of the rigid body

Parameters:

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)

set_height(height: float) → None

Set the cylinder height

Parameters:

height (float) – cylinder height

Example:

>>> prim.set_height(2.0)

set_linear_velocity(velocity: ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters:

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_mass(mass: float) → None

Set the mass of the rigid body

Parameters:

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the base radius

Parameters:

radius (float) – base radius

Example:

>>> prim.set_radius(1.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_sleep_threshold(threshold: float) → None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters:

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class DynamicSphere(

prim_path: str,

name: str = 'dynamic_sphere',

position: ndarray | None = None,

translation: ndarray | None = None,

orientation: ndarray | None = None,

scale: ndarray | None = None,

visible: bool | None = None,

color: ndarray | None = None,

radius: ndarray | None = None,

visual_material: VisualMaterial | None = None,

physics_material: PhysicsMaterial | None = None,

mass: float | None = None,

density: float | None = None,

linear_velocity: Sequence[float] | None = None,

angular_velocity: Sequence[float] | None = None,

)

Bases: SingleRigidPrim, FixedSphere

High level wrapper to create/encapsulate a dynamic sphere

Note

Dynamic spheres (Sphere shape) have collisions (Collider API) and rigid body dynamics (Rigid Body API)

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “dynamic_sphere”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• color (Optional[np.ndarray], optional) – color of the visual shape. Defaults to None, which means 50% gray

• radius (Optional[float], optional) – sphere radius. Defaults to None.

• visual_material (Optional[VisualMaterial], optional) – visual material to be applied to the held prim. Defaults to None. If not specified, a default visual material will be added.

• physics_material (Optional[PhysicsMaterial], optional) – physics material to be applied to the held prim. Defaults to None. If not specified, a default physics material will be added.

• mass (Optional[float], optional) – mass in kg. Defaults to None.

• density (Optional[float], optional) – density. Defaults to None.

• linear_velocity (Optional[np.ndarray], optional) – linear velocity in the world frame. Defaults to None.

• angular_velocity (Optional[np.ndarray], optional) – angular velocity in the world frame. Defaults to None.

Example:

>>> from isaacsim.core.api.objects import DynamicSphere
>>> import numpy as np
>>>
>>> # create a red dynamic sphere of mass 1kg at the given path
>>> prim = DynamicSphere(prim_path="/World/Xform/Sphere", color=np.array([1.0, 0.0, 0.0]), mass=1.0)
>>> prim
<isaacsim.core.api.objects.sphere.DynamicSphere object at 0x7f4deaf8f010>

apply_physics_material(

physics_material: PhysicsMaterial,

weaker_than_descendants: bool = False,

)

Used to apply physics material to the held prim and optionally its descendants.

Parameters:

• physics_material (PhysicsMaterial) – physics material to be applied to the held prim. This where you want to define friction, restitution..etc. Note: if a physics material is not defined, the defaults will be used from PhysX.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import PhysicsMaterial
>>>
>>> # create a rigid body physical material
>>> material = PhysicsMaterial(
...     prim_path="/World/physics_material/aluminum",  # path to the material prim to create
...     dynamic_friction=0.4,
...     static_friction=1.1,
...     restitution=0.1
... )
>>> prim.apply_physics_material(material)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_rigid_body_physics() → None

Disable the rigid body physics

When disabled, the object will not be moved by external forces such as gravity and collisions

Example:

>>> prim.disable_rigid_body_physics()

enable_rigid_body_physics() → None

Enable the rigid body physics

When enabled, the object will be moved by external forces such as gravity and collisions

Example:

>>> prim.enable_rigid_body_physics()

property geom: pxr.UsdGeom.Gprim

Returns: UsdGeom.Gprim: USD geometry object encapsulated.

get_angular_velocity()

Get the angular velocity of the rigid body

Returns:

current angular velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

get_applied_physics_material() → PhysicsMaterial

Return the current applied physics material in case it was applied using apply_physics_material or not.

Returns:

the current applied physics material.

Return type:

PhysicsMaterial

Example:

>>> # given a physics material applied
>>> prim.get_applied_physics_material()
<isaacsim.core.api.materials.physics_material.PhysicsMaterial object at 0x7fb66c30cd30>

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_collision_approximation() → str

Get the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Returns:

approximation used for collision

Return type:

str

Example:

>>> prim.get_collision_approximation()
none

get_collision_enabled() → bool

Check if the Collision API is enabled

Returns:

True if the Collision API is enabled. Otherwise False

Return type:

bool

Example:

>>> prim.get_collision_enabled()
True

get_com() → float

Get the center of mass pose of the rigid body

Returns:

position of the center of mass of the rigid body. np.ndarray: orientation of the center of mass of the rigid body.

Return type:

np.ndarray

get_contact_force_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed contact forces between the prims in the view and the filter prims including the normal contact forces, normal directions, contact points, separations. The number of contacts per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_contact_force_matrix(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the contact forces between the prims in the view and the filter prims. i.e., a matrix of dimension (self._contact_view.num_filters, 3) where num_filters is the determined according to the filter_paths_expr parameter.

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (self._geometry_prim_view._contact_view.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor]

get_contact_offset() → float

Get the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

contact offset of the collision shape. Default value is -inf, means default is picked by simulation.

Return type:

float

Example:

>>> prim.get_contact_offset()
-inf

get_current_dynamic_state() → DynamicState

Get the current rigid body state (position, orientation and linear and angular velocities)

Returns:

the dynamic state of the rigid body prim

Return type:

DynamicState

Example:

>>> # for the example the rigid body is in free fall
>>> state = prim.get_current_dynamic_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f740b36f670>
>>> state.position
[  0.99999857   2.0000017  -74.2862    ]
>>> state.orientation
[ 1.0000000e+00 -2.3961178e-07 -4.9891562e-09  4.9388258e-09]
>>> state.linear_velocity
[  0.        0.      -38.09554]
>>> state.angular_velocity
[0. 0. 0.]

get_default_state() → DynamicState

Get the default rigid body state (position, orientation and linear and angular velocities)

Returns:

returns the default state of the prim that is used after each reset

Return type:

DynamicState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.DynamicState object at 0x7f7411fcbe20>
>>> state.position
[-7.8622378e-07  1.4450421e-06  1.6135601e-07]
>>> state.orientation
[ 9.9999994e-01 -2.7194994e-07  2.9607077e-07  2.7016510e-08]
>>> state.linear_velocity
[0. 0. 0.]
>>> state.angular_velocity
[0. 0. 0.]

get_density() → float

Get the density of the rigid body

Returns:

density of the rigid body.

Return type:

float

Example:

>>> prim.get_density()
0

get_friction_data(

dt: float = 1.0,

) → ndarray | Tensor

If the object is initialized with filter_paths_expr list, this method returns the detailed friction forces between the prims in the view and the filter prims including the tangential forces, and points. The number of points per pair is determined from a static tensor of dimension (self._contact_view.num_filters) while the starting index of the associated contact in the above tensors is determined from another static tensor of dimension (self._contact_view.num_filters).

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), as well as two tensors with shape (self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

get_linear_velocity() → ndarray

Get the linear velocity of the rigid body

Returns:

current linear velocity of the the rigid prim. Shape (3,).

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[ 1.0812164e-04  6.1415871e-05 -2.1341663e-04]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_mass() → float

Get the mass of the rigid body

Returns:

mass of the rigid body in kg.

Return type:

float

Example:

>>> prim.get_mass()
0

get_min_torsional_patch_radius() → float

Get the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_min_torsional_patch_radius()
0.0

get_net_contact_forces(

dt: float = 1.0,

) → ndarray | Tensor

If contact forces of the prims in the view are tracked, this method returns the net contact forces on prims. i.e., a matrix of dimension (1, 3)

Parameters:

dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Net contact forces of the prims with shape (3).

Return type:

Union[np.ndarray, torch.Tensor]

get_radius() → float

Get the sphere radius

Returns:

sphere radius

Return type:

float

Example:

>>> prim.get_radius()
1.0

get_rest_offset() → float

Get the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Returns:

rest offset of the collision shape.

Return type:

float

Example:

>>> prim.get_rest_offset()
-inf

get_sleep_threshold() → float

Get the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Returns:

Mass-normalized kinetic energy threshold below which

an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Return type:

float

Example:

>>> prim.get_sleep_threshold()
5e-05

get_torsional_patch_radius() → float

Get the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Returns:

radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Return type:

float

Example:

>>> prim.get_torsional_patch_radius()
0.0

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the rigid body in stage

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

set_collision_approximation(

approximation_type: str,

) → None

Set the collision approximation

Approximation	Full name	Description
"none"	Triangle Mesh	The mesh geometry is used directly as a collider without any approximation
"convexDecomposition"	Convex Decomposition	A convex mesh decomposition is performed. This results in a set of convex mesh colliders
"convexHull"	Convex Hull	A convex hull of the mesh is generated and used as the collider
"boundingSphere"	Bounding Sphere	A bounding sphere is computed around the mesh and used as a collider
"boundingCube"	Bounding Cube	An optimally fitting box collider is computed around the mesh
"meshSimplification"	Mesh Simplification	A mesh simplification step is performed, resulting in a simplified triangle mesh collider
"sdf"	SDF Mesh	SDF (Signed-Distance-Field) use high-detail triangle meshes as collision shape
"sphereFill"	Sphere Approximation	A sphere mesh decomposition is performed. This results in a set of sphere colliders

Note

Use Convex Decomposition or SDF (Signed-Distance-Field) tri-meshes to capture details better

Warning

Switching to Convex Decomposition or SDF (Signed-Distance-Field) will have a simulation performance impact due to higher computational cost

Parameters:

approximation_type (str) – approximation used for collision

Example:

>>> prim.set_collision_approximation("convexDecomposition")

set_collision_enabled(enabled: bool) → None

Enable/disable the Collision API

Parameters:

enabled (bool) – Whether to enable or disable the Collision API

Example:

>>> # disable collisions
>>> prim.set_collision_enabled(False)

set_com(

position: ndarray,

orientation: ndarray,

) → None

Set the center of mass pose of the rigid body

Parameters:

• position (np.ndarray) – center of mass position. Shape (3,).

• orientation (np.ndarray) – center of mass orientation. Shape (4,).

set_contact_offset(offset: float) → None

Set the contact offset

Shapes whose distance is less than the sum of their contact offset values will generate contacts

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Contact offset of a collision shape. Allowed range [maximum(0, rest_offset), 0]. Default value is -inf, means default is picked by simulation based on the shape extent.

Example:

>>> prim.set_contact_offset(0.02)

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

linear_velocity: ndarray | None = None,

angular_velocity: ndarray | None = None,

) → None

Set the default state of the prim (position, orientation and linear and angular velocities), that will be used after each reset

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• linear_velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

• angular_velocity (np.ndarray) – angular velocity to set the rigid prim to. Shape (3,).

Example:

>>> prim.set_default_state(
...     position=np.array([1.0, 2.0, 3.0]),
...     orientation=np.array([1.0, 0.0, 0.0, 0.0]),
...     linear_velocity=np.array([0.0, 0.0, 0.0]),
...     angular_velocity=np.array([0.0, 0.0, 0.0])
... )
>>>
>>> prim.post_reset()

set_density(density: float) → None

Set the density of the rigid body

Parameters:

mass (float) – density of the rigid body.

Example:

>>> prim.set_density(0.9)

set_linear_velocity(velocity: ndarray)

Set the linear velocity of the rigid body in stage

Warning

This method will immediately set the rigid prim state

Parameters:

velocity (np.ndarray) – linear velocity to set the rigid prim to. Shape (3,).

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_mass(mass: float) → None

Set the mass of the rigid body

Parameters:

mass (float) – mass of the rigid body in kg.

Example:

>>> prim.set_mass(1.0)

set_min_torsional_patch_radius(radius: float) → None

Set the minimum radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – minimum radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_min_torsional_patch_radius(0.05)

set_radius(radius: float) → None

Set the sphere radius

Parameters:

radius (float) – sphere radius

Example:

>>> prim.set_radius(2.0)

set_rest_offset(offset: float) → None

Set the rest offset

Two shapes will come to rest at a distance equal to the sum of their rest offset values. If the rest offset is 0, they should converge to touching exactly

Search for Advanced Collision Detection in PhysX docs for more details

Warning

The contact offset must be positive and greater than the rest offset

Parameters:

offset (float) – Rest offset of a collision shape. Allowed range [-max_float, contact_offset. Default value is -inf, means default is picked by simulation. For rigid bodies its zero.

Example:

>>> prim.set_rest_offset(0.01)

set_sleep_threshold(threshold: float) → None

Set the threshold for the rigid body to enter a sleep state

Search for Rigid Body Dynamics > Sleeping in PhysX docs for more details

Parameters:

threshold (float) – Mass-normalized kinetic energy threshold below which an actor may go to sleep. Range: [0, inf) Defaults: 0.00005 * tolerancesSpeed* tolerancesSpeed Units: distance^2 / second^2.

Example:

>>> prim.set_sleep_threshold(1e-5)

set_torsional_patch_radius(radius: float) → None

Set the radius of the contact patch used to apply torsional friction

Search for “Torsional Patch Radius” in PhysX docs for more details

Parameters:

radius (float) – radius of the contact patch used to apply torsional friction. Allowed range [0, max_float].

Example:

>>> prim.set_torsional_patch_radius(0.1)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

Physics Context

class PhysicsContext(

physics_dt: float | None = None,

prim_path: str = '/physicsScene',

sim_params: dict | None = None,

set_defaults: bool = True,

)

Bases: object

Provides high level functions to deal with a physics scene and its settings. This will create a

a PhysicsScene prim at the specified prim path in case there is no PhysicsScene present in the current stage. If there is a PhysicsScene present, it will discard the prim_path specified and sets the default settings on the current PhysicsScene found.

Parameters:

• physics_dt (float, optional) – specifies the physics_dt of the simulation. Defaults to 1.0 / 60.0.

• prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

• set_defaults (bool, optional) – set to True to use the defaults physics parameters [physics_dt = 1.0/ 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

Raises:

• Exception – If prim_path is not absolute.

• Exception – if prim_path already exists and its type is not a PhysicsScene.

property prim_path

property device: str

property use_gpu_sim

property use_gpu_pipeline

property use_fabric

warm_start()

get_current_physics_scene_prim() → pxr.Usd.Prim | None

Used to return the PhysicsScene prim in stage by traversing the stage.

Returns:

returns a PhysicsScene prim if found in current stage. Otherwise, None.

Return type:

Optional[Usd.Prim]

set_physics_dt(

dt: float = 0.016666666666666666,

substeps: int = 1,

) → None

Sets the physics dt on the PhysicsScene

Parameters:

• dt (float, optional) – physics dt. Defaults to 1.0/60.0.

• substeps (int, optional) – number of physics steps to run for before rendering a frame. Defaults to 1.

Raises:

• Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

• ValueError – Physics dt must be a >= 0.

• ValueError – Physics dt must be a <= 1.0.

get_physics_dt() → float

Returns the current physics dt.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

physics dt.

Return type:

float

enable_fabric(enable)

enable_ccd(flag: bool) → None

Enables a second broad phase after integration that makes it possible to prevent objects from tunneling

through each other.

Parameters:

flag (bool) – enables or disables ccd on the PhysicsScene

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

enable_residual_reporting(flag: bool)

Set the physx scene flag to enable/disable solver residual reporting.

Parameters:

flag (bool) – enables or disables scene residuals on the PhysicsScene

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_solver_velocity_residual(report_max: bool = True)

Enable physics scene residual reporting API and chooses between RMS vs Max criteri for velocity residuals.

Parameters:

report_max (bool) – Use the max residual criterion if True, otherwise use the RMS criterion.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_solver_position_residual(report_max: bool = True)

Enable physics scene residual reporting API and chooses between RMS vs Max criteri for position residuals.

Parameters:

report_max (bool) – Use the max residual criterion if True, otherwise use the RMS criterion.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

is_ccd_enabled() → bool

Checks if ccd is enabled.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

True if ccd is enabled, otherwise False.

Return type:

bool

enable_stablization(flag: bool) → None

Enables additional stabilization pass in the solver.

Parameters:

flag (bool) – enables or disables stabilization on the PhysicsScene

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

is_stablization_enabled() → bool

Checks if stabilization is enabled.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

True if stabilization is enabled, otherwise False.

Return type:

bool

enable_gpu_dynamics(flag: bool) → None

Enables gpu dynamics pipeline, required for deformables for instance.

Parameters:

flag (bool) – enables or disables gpu dynamics on the PhysicsScene

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

is_gpu_dynamics_enabled() → bool

Checks if Gpu Dynamics is enabled.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

True if Gpu Dynamics is enabled, otherwise False.

Return type:

bool

set_broadphase_type(broadcast_type: str) → None

Broadcast phase algorithm used in simulation.

Parameters:

broadcast_type (str) – type of broadcasting to be used, can be “MBP”

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_broadphase_type() → str

Gets current broadcast phase algorithm type.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

Broadcast phase algorithm used.

Return type:

str

set_solver_type(solver_type: str) → None

solver used for simulation.

Parameters:

solver_type (str) – can be “TGS” or “PGS”. for references look at..

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_solver_type() → str

Gets current solver type.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

solver used for simulation.

Return type:

str

set_gravity(value: float) → None

sets the gravity direction and magnitude.

Parameters:

value (float) – gravity value to be used in simulation.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

get_gravity() → Tuple[List, float]

Gets current gravity.

Raises:

Exception – If the prim path registered in context doesn’t correspond to a valid prim path currently.

Returns:

returns a tuple, first element corresponds to the gravity direction vector and second element is the magnitude.

Return type:

Tuple[list, float]

set_physx_update_transformations_settings(

update_to_usd: bool | None = None,

update_velocities_to_usd: bool | None = None,

output_velocities_local_space: bool | None = None,

) → None

Sets how physx syncs with the usd when transformations are updated.

Parameters:

• update_to_usd (bool, optional) – Updates to USD the transformations. Defaults to True.

• update_velocities_to_usd (bool, optional) – Updates Velocities to USD. Defaults to True.

• output_velocities_local_space (bool, optional) – Output the velocities in the local frame and not the world frame. Defaults to False.

get_physx_update_transformations_settings() → Tuple[bool, bool, bool, bool]

Gets how physx syncs with the usd when transformations are updated.

Returns:

[update_to_usd, update_velocities_to_usd, output_velocities_local_space]

Return type:

Tuple[bool, bool, bool, bool]

set_invert_collision_group_filter(

invert_collision_group_filter: bool,

) → None

[summary]

Parameters:

invert_collision_group_filter (bool) – [description]

Raises:

Exception – [description]

get_invert_collision_group_filter() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_bounce_threshold(value: float) → None

[summary]

Parameters:

value (float) – [description]

Raises:

Exception – [description]

get_bounce_threshold() → float

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

float

set_friction_offset_threshold(value: float) → None

[summary]

Parameters:

value (float) – [description]

Raises:

Exception – [description]

get_friction_offset_threshold() → float

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

float

set_friction_correlation_distance(value: float) → None

[summary]

Parameters:

value (float) – [description]

Raises:

Exception – [description]

get_friction_correlation_distance() → float

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

float

set_enable_scene_query_support(

enable_scene_query_support: bool,

) → None

Sets the Enable Scene Query Support attribute in Physx Scene

Parameters:

enable_scene_query_support (bool) – Whether to enable scene query support

Raises:

Exception – [description]

get_enable_scene_query_support() → bool

Retrieves the Enable Scene Query Support attribute in Physx Scene

Raises:

Exception – [description]

Returns:

enable scene query support attribute

Return type:

bool

set_gpu_max_rigid_contact_count(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_max_rigid_contact_count() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_max_rigid_patch_count(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_max_rigid_patch_count() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_found_lost_pairs_capacity(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_found_lost_pairs_capacity() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_found_lost_aggregate_pairs_capacity(

value: int,

) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_found_lost_aggregate_pairs_capacity() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_total_aggregate_pairs_capacity(

value: int,

) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_total_aggregate_pairs_capacity() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_max_soft_body_contacts(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_max_soft_body_contacts() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_max_particle_contacts(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_max_particle_contacts() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_heap_capacity(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_heap_capacity() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_temp_buffer_capacity(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_temp_buffer_capacity() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_max_num_partitions(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_max_num_partitions() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

set_gpu_collision_stack_size(value: int) → None

[summary]

Parameters:

value (int) – [description]

Raises:

Exception – [description]

get_gpu_collision_stack_size() → int

[summary]

Raises:

Exception – [description]

Returns:

[description]

Return type:

int

Robots

class Robot(

prim_path: str,

name: str = 'robot',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool = True,

articulation_controller: ArticulationController | None = None,

)

Bases: SingleArticulation

Implementation (on SingleArticulation class) to deal with an articulation prim as a robot

Warning

The robot (articulation) object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create.

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “robot”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

• articulation_controller (Optional[ArticulationController], optional) – a custom ArticulationController which inherits from it. Defaults to creating the basic ArticulationController.

Example:

>>> import isaacsim.core.utils.stage as stage_utils
>>> from isaacsim.core.api.robots import Robot
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> prim_path = "/World/envs/env_0/panda"
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path)
>>>
>>> # wrap the prim as a robot (articulation)
>>> prim = Robot(prim_path=prim_path, name="franka_panda")
>>> print(prim)
<isaacsim.core.api.robots.robot.Robot object at 0x7fdd4875a1d0>

post_reset() → None

Reset the robot to its default state

Note

For a robot, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

apply_action(

control_actions: ArticulationAction,

) → None

Apply joint positions, velocities and/or efforts to control an articulation

Parameters:

• control_actions (ArticulationAction) – actions to be applied for next physics step.

• indices (Optional[Union[list, np.ndarray]], optional) – degree of freedom indices to apply actions to. Defaults to all degrees of freedom.

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

• For position control, set relatively high stiffness and low damping (to reduce vibrations)

• For velocity control, stiffness must be set to zero with a non-zero damping

• For effort control, stiffness and damping must be set to zero

Example:

>>> from isaacsim.core.utils.types import ArticulationAction
>>>
>>> # move all the robot joints to the indicated position
>>> action = ArticulationAction(joint_positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>> prim.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> action = ArticulationAction(joint_positions=np.array([0.0, 0.0]), joint_indices=np.array([7, 8]))
>>> prim.apply_action(action)

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

disable_gravity() → None

Keep gravity from affecting the robot

Example:

>>> prim.disable_gravity()

property dof_names: List[str]

List of prim names for each DOF.

Returns:

prim names

Return type:

list(string)

Example:

>>> prim.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']

property dof_properties: ndarray

Articulation DOF properties

DOF properties

Index	Property name	Description
0	type	DOF type: invalid/unknown/uninitialized (0), rotation (1), translation (2)
1	hasLimits	Whether the DOF has limits
2	lower	Lower DOF limit (in radians or meters)
3	upper	Upper DOF limit (in radians or meters)
4	driveMode	Drive mode for the DOF: force (1), acceleration (2)
5	maxVelocity	Maximum DOF velocity. In radians/s, or stage_units/s
6	maxEffort	Maximum DOF effort. In N or N*stage_units
7	stiffness	DOF stiffness
8	damping	DOF damping

Returns:

named NumPy array of shape (num_dof, 9)

Return type:

np.ndarray

Example:

>>> # get properties for all DOFs
>>> prim.dof_properties
[(1,  True, -2.8973,  2.8973, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -1.7628,  1.7628, 1, 1.0000000e+01, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -3.0718, -0.0698, 1, 5.9390470e+36, 5220., 60000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 5.9390470e+36,  720., 25000., 3000.)
 (1,  True, -0.0175,  3.7525, 1, 5.9390470e+36,  720., 15000., 3000.)
 (1,  True, -2.8973,  2.8973, 1, 1.0000000e+01,  720.,  5000., 3000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)
 (2,  True,  0.    ,  0.04  , 1, 3.4028235e+38,  720.,  6000., 1000.)]
>>>
>>> # property names
>>> prim.dof_properties.dtype.names
('type', 'hasLimits', 'lower', 'upper', 'driveMode', 'maxVelocity', 'maxEffort', 'stiffness', 'damping')
>>>
>>> # get DOF upper limits
>>> prim.dof_properties["upper"]
[ 2.8973  1.7628  2.8973 -0.0698  2.8973  3.7525  2.8973  0.04    0.04  ]
>>>
>>> # get the last DOF (panda_finger_joint2) upper limit
>>> prim.dof_properties["upper"][8]  # or prim.dof_properties[8][3]
0.04

enable_gravity() → None

Gravity will affect the robot

Example:

>>> prim.enable_gravity()

get_angular_velocity() → ndarray

Get the angular velocity of the root articulation prim

Returns:

3D angular velocity vector. Shape (3,)

Return type:

np.ndarray

Example:

>>> prim.get_angular_velocity()
[0. 0. 0.]

get_applied_action() → ArticulationAction

Get the last applied action

Returns:

last applied action. Note: a dictionary is used as the object’s string representation

Return type:

ArticulationAction

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]
>>> prim.get_applied_action()
{'joint_positions': [0.0, -1.0, 0.0, -2.200000047683716, 0.0, 2.4000000953674316,
                     0.800000011920929, 0.03999999910593033, 0.03999999910593033],
 'joint_velocities': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
 'joint_efforts': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]}

get_applied_joint_efforts(

joint_indices: List | ndarray | None = None,

) → ndarray

Get the efforts applied to the joints set by the set_joint_efforts method

Parameters:

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises:

Exception – If the handlers are not initialized

Returns:

all or selected articulation joint applied efforts

Return type:

np.ndarray

Example:

>>> # get all applied joint efforts
>>> prim.get_applied_joint_efforts()
[ 0.  0.  0.  0.  0.  0.  0.  0.  0.]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_applied_joint_efforts(joint_indices=np.array([7, 8]))
[0.  0.]

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_articulation_body_count() → int

Get the number of bodies (links) that make up the articulation

Returns:

amount of bodies

Return type:

int

Example:

>>> prim.get_articulation_body_count()
12

get_articulation_controller() → ArticulationController

Get the articulation controller

Note

If no articulation_controller was passed during class instantiation, a default controller of type ArticulationController (a Proportional-Derivative controller that can apply position targets, velocity targets and efforts) will be used

Returns:

articulation controller

Return type:

ArticulationController

Example:

>>> prim.get_articulation_controller()
<isaacsim.core.api.controllers.articulation_controller.ArticulationController object at 0x7f04a0060190>

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_dof_index(dof_name: str) → int

Get a DOF index given its name

Parameters:

dof_name (str) – name of the DOF

Returns:

DOF index

Return type:

int

Example:

>>> prim.get_dof_index("panda_finger_joint2")
8

get_enabled_self_collisions() → int

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Returns:

self collisions flag (boolean interpreted as int)

Return type:

int

Example:

>>> prim.get_enabled_self_collisions()
0

get_joint_positions(

joint_indices: List | ndarray | None = None,

) → ndarray

Get the articulation joint positions

Parameters:

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns:

all or selected articulation joint positions

Return type:

np.ndarray

Example:

>>> # get all joint positions
>>> prim.get_joint_positions()
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00  6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>>
>>> # get finger positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_positions(joint_indices=np.array([7, 8]))
[0.03991237  3.9999999e-02]

get_joint_velocities(

joint_indices: List | ndarray | None = None,

) → ndarray

Get the articulation joint velocities

Parameters:

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Returns:

all or selected articulation joint velocities

Return type:

np.ndarray

Example:

>>> # get all joint velocities
>>> prim.get_joint_velocities()
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  3.48245539e-02  8.84692147e-02  5.40335372e-04 1.02849208e-05]
>>>
>>> # get finger velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_joint_velocities(joint_indices=np.array([7, 8]))
[5.4033537e-04 1.0284921e-05]

get_joints_default_state() → JointsState

Get the default joint states (positions and velocities).

Returns:

an object that contains the default joint positions and velocities

Return type:

JointsState

Example:

>>> state = prim.get_joints_default_state()
>>> state
<isaacsim.core.utils.types.JointsState object at 0x7f04a0061240>
>>>
>>> state.positions
[ 0.012  -0.57000005  0.  -2.81  0.  3.037  0.785398  0.04  0.04 ]
>>> state.velocities
[0. 0. 0. 0. 0. 0. 0. 0. 0.]

get_joints_state() → JointsState

Get the current joint states (positions and velocities)

Returns:

an object that contains the current joint positions and velocities

Return type:

JointsState

Example:

>>> state = prim.get_joints_state()
>>> state
<isaacsim.core.utils.types.JointsState object at 0x7f02f6df57b0>
>>>
>>> state.positions
[ 1.1999920e-02 -5.6962633e-01  1.3480479e-08 -2.8105433e+00 6.8284894e-06
  3.0301569e+00  7.3234749e-01  3.9912373e-02  3.9999999e-02]
>>> state.velocities
[ 1.91603772e-06 -7.67638255e-03 -2.19138826e-07  1.10636465e-02 -4.63412944e-05
  245539e-02  8.84692147e-02  5.40335372e-04  1.02849208e-05]

get_linear_velocity() → ndarray

Get the linear velocity of the root articulation prim

Returns:

3D linear velocity vector. Shape (3,)

Return type:

np.ndarray

Example:

>>> prim.get_linear_velocity()
[0. 0. 0.]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_measured_joint_efforts(

joint_indices: List | ndarray | None = None,

) → ndarray

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters:

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises:

Exception – If the handlers are not initialized

Returns:

all or selected articulation joint measured efforts

Return type:

np.ndarray

Example:

>>> # get all joint efforts
>>> prim.get_measured_joint_efforts()
[ 2.7897308e-06 -6.9083519e+00 -3.6398471e-06  1.9158335e+01 -4.3552645e-06
  1.1866090e+00 -4.7079347e-06  3.2339853e-04 -3.2044132e-04]
>>>
>>> # get finger efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> prim.get_measured_joint_efforts(joint_indices=np.array([7, 8]))
[ 0.0003234  -0.00032044]

get_measured_joint_forces(

joint_indices: List | ndarray | None = None,

) → ndarray

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prim._articulation_view._metadata.joint_names  # list of names
prim._articulation_view._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters:

joint_indices (Optional[Union[List, np.ndarray]], optional) – indices to specify which joints to read. Defaults to None (all joints)

Raises:

Exception – If the handlers are not initialized

Returns:

measured joint forces and torques. Shape is (num_joint + 1, 6). Row index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type:

np.ndarray

Example:

>>> # get all measured joint forces and torques
>>> prim.get_measured_joint_forces()
[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 1.4995076e+02  4.2574748e-06  5.6364370e-04  4.8701895e-05 -6.9072924e+00  3.1881387e-05]
 [-2.8971717e-05 -1.0677823e+02 -6.8384506e+01 -6.9072924e+00 -5.4927128e-05  6.1222494e-07]
 [ 8.7120995e+01 -4.3871860e-05 -5.5795174e+01  5.3687054e-05 -2.4538563e+01  1.3333466e-05]
 [ 5.3519474e-05 -4.8109909e+01  6.0709282e+01  1.9157074e+01 -5.9258469e-05  8.2744418e-07]
 [-3.1691040e+01  2.3313689e-04  3.9990173e+01 -5.8968733e-05 -1.1863431e+00  2.2335558e-05]
 [-1.0809851e-04  1.5340537e+01 -1.5458489e+01  1.1863426e+00  6.1094368e-05 -1.5940281e-05]
 [-7.5418940e+00 -5.0814648e+00 -5.6512990e+00 -5.6385466e-05  3.8859999e-01 -3.4943256e-01]
 [ 4.7421460e+00 -3.1945827e+00  3.5528181e+00  5.5852943e-05  8.4794536e-03  7.6405057e-03]
 [ 4.0760727e+00  2.1640673e-01 -4.0513167e+00 -5.9565349e-04  1.1407082e-02  2.1432268e-06]
 [ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]
>>>
>>> # get measured joint force and torque for the fingers
>>> metadata = prim._articulation_view._metadata
>>> joint_indices = 1 + np.array([
...     metadata.joint_indices["panda_finger_joint1"],
...     metadata.joint_indices["panda_finger_joint2"],
... ])
>>> joint_indices
[10 11]
>>> prim.get_measured_joint_forces(joint_indices)
[[ 5.1680198e-03 -9.7754575e-02 -9.7093947e-02 -8.4155556e-12 -1.2910691e-12 -1.9347857e-11]
 [-5.1910793e-03  9.7588278e-02 -9.7106412e-02  8.4155573e-12  1.2910637e-12 -1.9347855e-11]]

get_position_residual(report_max: bool | None = True) → float

Get physics solver position residuals for articulations. This is the residual across all joints that are part of articulations.

The solver residuals are computed according to impulse variation normalized by the effective mass.

Parameters:

report_max (Optional[bool]) – whether to report max or RMS residual. Defaults to True, i.e. max criteria

Returns:

solver position/velocity max/rms residual.

Return type:

float

get_sleep_threshold() → float

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Returns:

sleep threshold

Return type:

float

Example:

>>> prim.get_sleep_threshold()
0.005

get_solver_position_iteration_count() → int

Get the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns:

position iteration count

Return type:

int

Example:

>>> prim.get_solver_position_iteration_count()
32

get_solver_velocity_iteration_count() → int

Get the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Returns:

velocity iteration count

Return type:

int

Example:

>>> prim.get_solver_velocity_iteration_count()
32

get_stabilization_threshold() → float

Get the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Returns:

stabilization threshold

Return type:

float

Example:

>>> prim.get_stabilization_threshold()
0.0009999999

get_velocity_residual(report_max: bool | None = True) → float

Get physics solver velocity residuals for articulations. This is the residual across all joints that are part of articulations.

The solver residuals are computed according to impulse variation normalized by the effective mass.

Parameters:

report_max (Optional[bool]) – whether to report max or RMS residual. Defaults to True, i.e. max criteria

Returns:

solver velocity max/rms residual.

Return type:

float

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

get_world_velocity() → ndarray

Get the articulation root velocity

Returns:

current velocity of the the root prim. Shape (3,).

Return type:

np.ndarray

property handles_initialized: bool

Check if articulation handler is initialized

Returns:

whether the handler was initialized

Return type:

bool

Example:

>>> prim.handles_initialized
True

initialize(

physics_sim_view: omni.physics.tensors.SimulationView | None = None,

) → None

Create a physics simulation view if not passed and an articulation view using PhysX tensor API

Note

If the articulation has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

property num_bodies: int

Number of articulation links

Returns:

number of links

Return type:

int

Example:

>>> prim.num_bodies
9

property num_dof: int

Number of DOF of the articulation

Returns:

amount of DOFs

Return type:

int

Example:

>>> prim.num_dof
9

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_angular_velocity(velocity: ndarray) → None

Set the angular velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – 3D angular velocity vector. Shape (3,)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_angular_velocity(np.array([0.1, 0.0, 0.0]))

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_enabled_self_collisions(flag: bool) → None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters:

flag (bool) – whether to enable self collisions

Example:

>>> prim.set_enabled_self_collisions(True)

set_joint_efforts(

efforts: ndarray,

joint_indices: List | ndarray | None = None,

) → None

Set the articulation joint efforts

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters:

• efforts (np.ndarray) – articulation joint efforts

• joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint efforts to 0.0
>>> prim.set_joint_efforts(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> prim.set_joint_efforts(np.array([10, 10]), joint_indices=np.array([7, 8]))

set_joint_positions(

positions: ndarray,

joint_indices: List | ndarray | None = None,

) → None

Set the articulation joint positions

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters:

• positions (np.ndarray) – articulation joint positions

• joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joints
>>> prim.set_joint_positions(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]))
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> prim.set_joint_positions(np.array([0.04, 0.04]), joint_indices=np.array([7, 8]))

set_joint_velocities(

velocities: ndarray,

joint_indices: List | ndarray | None = None,

) → None

Set the articulation joint velocities

Warning

This method will immediately set the affected joints to the indicated value. Use the apply_action method to control robot joints.

Parameters:

• velocities (np.ndarray) – articulation joint velocities

• joint_indices (Optional[Union[list, np.ndarray]], optional) – indices to specify which joints to manipulate. Defaults to None (all joints)

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the robot joint velocities to 0.0
>>> prim.set_joint_velocities(np.array([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]))
>>>
>>> # set only the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.01
>>> prim.set_joint_velocities(np.array([-0.01, -0.01]), joint_indices=np.array([7, 8]))

set_joints_default_state(

positions: ndarray | None = None,

velocities: ndarray | None = None,

efforts: ndarray | None = None,

) → None

Set the joint default states (positions, velocities and/or efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• positions (Optional[np.ndarray], optional) – joint positions. Defaults to None.

• velocities (Optional[np.ndarray], optional) – joint velocities. Defaults to None.

• efforts (Optional[np.ndarray], optional) – joint efforts. Defaults to None.

Example:

>>> # configure default joint states
>>> prim.set_joints_default_state(
...     positions=np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]),
...     velocities=np.zeros(shape=(prim.num_dof,)),
...     efforts=np.zeros(shape=(prim.num_dof,))
... )
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_linear_velocity(velocity: ndarray) → None

Set the linear velocity of the root articulation prim

Warning

This method will immediately set the articulation state

Parameters:

velocity (np.ndarray) – 3D linear velocity vector. Shape (3,).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_linear_velocity, set_angular_velocity, set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> prim.set_linear_velocity(np.array([0.1, 0.0, 0.0]))

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(scale: Sequence[float] | None) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_sleep_threshold(threshold: float) → None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters:

threshold (float) – sleep threshold

Example:

>>> prim.set_sleep_threshold(0.01)

set_solver_position_iteration_count(count: int) → None

Set the solver (position) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters:

count (int) – position iteration count

Example:

>>> prim.set_solver_position_iteration_count(64)

set_solver_velocity_iteration_count(count: int)

Set the solver (velocity) iteration count for the articulation

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters:

count (int) – velocity iteration count

Example:

>>> prim.set_solver_velocity_iteration_count(64)

set_stabilization_threshold(threshold: float) → None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters:

threshold (float) – stabilization threshold

Example:

>>> prim.set_stabilization_threshold(0.005)

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_world_velocity(velocity: ndarray)

Set the articulation root velocity

Parameters:

velocity (np.ndarray) – linear and angular velocity to set the root prim to. Shape (6,).

class RobotView(

prim_paths_expr: str,

name: str = 'rigid_prim_view',

positions: ndarray | Tensor | None = None,

translations: ndarray | Tensor | None = None,

orientations: ndarray | Tensor | None = None,

scales: ndarray | Tensor | None = None,

visibilities: ndarray | Tensor | None = None,

)

Bases: Articulation

Implementation (on Articulation class) to deal with articulation prims as robots

This class wraps all matching articulations found at the regex provided at the prim_paths_expr argument

Warning

The robot (articulation) view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters:

• prim_paths_expr (str) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Franka” will match /World/Env1/Franka, /World/Env2/Franka, etc. (a non regex prim path can also be used to encapsulate one rigid prim).

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_prim_view”.

• positions (Optional[Union[np.ndarray, torch.Tensor]], optional) – default positions in the world frame of the prims. shape is (N, 3). Defaults to None, which means left unchanged.

• translations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default translations in the local frame of the prims (with respect to its parent prims). shape is (N, 3). Defaults to None, which means left unchanged.

• orientations (Optional[Union[np.ndarray, torch.Tensor]], optional) – default quaternion orientations in the world/ local frame of the prims (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (N, 4).

• scales (Optional[Union[np.ndarray, torch.Tensor]], optional) – local scales to be applied to the prim’s dimensions in the view. shape is (N, 3). Defaults to None, which means left unchanged.

• visibilities (Optional[Union[np.ndarray, torch.Tensor]], optional) – set to false for an invisible prim in the stage while rendering. shape is (N,). Defaults to None.

Example:

>>> import isaacsim.core.utils.stage as stage_utils
>>> from isaacsim.core.cloner import GridCloner
>>> from isaacsim.core.api.robots import RobotView
>>> from pxr import UsdGeom
>>>
>>> usd_path = "/home/<user>/Documents/Assets/Robots/Franka/franka_alt_fingers.usd"
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # load the Franka Panda robot USD file
>>> stage_utils.add_reference_to_stage(usd_path, prim_path=f"{env_zero_path}/panda")  # /World/envs/env_0/panda
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=1.5)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> cloner.clone(source_prim_path=env_zero_path, prim_paths=cloner.generate_paths("/World/envs/env", num_envs))
>>>
>>> # wrap all robots
>>> prims = RobotView(prim_paths_expr="/World/envs/env.*/panda", name="franka_panda_view")
>>> print(prims)
<isaacsim.core.api.robots.robot_view.RobotView object at 0x7f12785a5fc0>

post_reset() → None

Reset the robots to their default states

Note

For the robots, in addition to configuring the root prim’s default positions and spatial orientations (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) and the joint’s stiffness and dampings (defined via the set_gains method) are imposed

Example:

>>> prims.post_reset()

apply_action(

control_actions: ArticulationActions,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Apply joint positions (targets), velocities (targets) and/or efforts to control an articulation

Note

This method can be used instead of the separate set_joint_position_targets, set_joint_velocity_targets and set_joint_efforts

Parameters:

• control_actions (ArticulationActions) – actions to be applied for next physics step.

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

• For position control, set relatively high stiffness and low damping (to reduce vibrations)

• For velocity control, stiffness must be set to zero with a non-zero damping

• For effort control, stiffness and damping must be set to zero

Example:

>>> from isaacsim.core.utils.types import ArticulationActions
>>>
>>> # move all the articulation joints to the indicated position.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> action = ArticulationActions(joint_positions=positions)
>>> prims.apply_action(action)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> action = ArticulationActions(joint_positions=positions, joint_indices=np.array([7, 8]))
>>> prims.apply_action(action, indices=np.array([0, 2, 4]))

apply_visual_materials(

visual_materials: VisualMaterial | List[VisualMaterial],

weaker_than_descendants: bool | List[bool] | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Apply visual material to the prims and optionally their prim descendants.

Parameters:

• visual_materials (Union[VisualMaterial, List[VisualMaterial]]) – visual materials to be applied to the prims. Currently supports PreviewSurface, OmniPBR and OmniGlass. If a list is provided then its size has to be equal the view’s size or indices size. If one material is provided it will be applied to all prims in the view.

• weaker_than_descendants (Optional[Union[bool, List[bool]]], optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False. If a list of visual materials is provided then a list has to be provided with the same size for this arg as well.

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Raises:

• Exception – length of visual materials != length of prims indexed

• Exception – length of visual materials != length of weaker descendants bools arg

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prims.apply_visual_materials(material)

property body_names: List[str]

List of prim names for each rigid body (link) of the articulations

Returns:

ordered names of bodies that corresponds to links for the articulations in the view

Return type:

List[str]

Example:

>>> prims.body_names
['panda_link0', 'panda_link1', 'panda_link2', 'panda_link3', 'panda_link4', 'panda_link5',
 'panda_link6', 'panda_link7', 'panda_link8', 'panda_hand', 'panda_leftfinger', 'panda_rightfinger']

property count: int

Returns:

Number of prims encapsulated in this view.

Return type:

int

Example:

>>> prims.count
5

property dof_names: List[str]

List of prim names for each DOF of the articulations

Returns:

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type:

List[str]

Example:

>>> prims.dof_names
['panda_joint1', 'panda_joint2', 'panda_joint3', 'panda_joint4', 'panda_joint5',
 'panda_joint6', 'panda_joint7', 'panda_finger_joint1', 'panda_finger_joint2']

get_angular_velocities(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the angular velocities of prims in the view.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

angular velocities of the prims in the view. shape is (M, 3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation angular velocities. Returned shape is (5, 3) for the example: 5 envs, angular (3)
>>> prims.get_angular_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation angular velocities for the first, middle and last of the 5 envs
>>> # Returned shape is (5, 3) for the example: 3 envs selected, angular (3)
>>> prims.get_angular_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]

get_applied_actions(

clone: bool = True,

) → ArticulationActions

Get the last applied actions

Parameters:

clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns:

current applied actions (i.e: current position targets and velocity targets)

Return type:

ArticulationActions

Example:

>>> # last applied action: joint_positions -> [0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04].
>>> # Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> actions = prims.get_applied_actions()
>>> actions
<isaacsim.core.utils.types.ArticulationActions object at 0x7f28af31d870>
>>> actions.joint_positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> actions.joint_velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> actions.joint_efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]

get_applied_joint_efforts(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the joint efforts of articulations in the view

This method will return the efforts set by the set_joint_efforts method

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint efforts of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all applied joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_applied_joint_efforts()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get finger applied efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_applied_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]

get_applied_visual_materials(

indices: ndarray | list | Tensor | warp.array | None = None,

) → List[VisualMaterial]

Get the current applied visual materials

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

a list of the current applied visual materials to the prims if its type is currently supported.

Return type:

List[VisualMaterial]

Example:

>>> # get all applied visual materials. Returned size is 5 for the example: 5 envs
>>> prims.get_applied_visual_materials()
[<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]
>>>
>>> # get the applied visual materials for the first, middle and last of the 5 envs. Returned size is 3
>>> prims.get_applied_visual_materials(indices=np.array([0, 2, 4]))
[<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>,
 <isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f829c165de0>]

get_armatures(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint armatures for articulations in the view. shape (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint armatures. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_armatures()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_armatures(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]

get_articulation_body_count() → int

Get the number of rigid bodies (links) of the articulations

Returns:

maximum number of rigid bodies (links) in the articulation

Return type:

int

Example:

>>> prims.get_articulation_body_count()
12

get_body_coms(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get rigid body center of mass (COM) of articulations in the view.

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body center of mass positions and orientations of articulations in the view. Position shape is (M, K, 3), orientation shape is (M, k, 4).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body center of mass. Returned shape is (5, 12, 3) for positions and (5, 12, 4) for orientations
>>> # for the example: 5 envs, 12 rigid bodies
>>> positions, orientations = prims.get_body_coms()
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]
  ...
  [0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]
  ...
  [1. 0. 0. 0.]
  [1. 0. 0. 0.]]]
>>>
>>> # get finger body center of mass: panda_leftfinger (10) and panda_rightfinger (11) for the first,
>>> # middle and last of the 5 envs. Returned shape is (3, 2, 3) for positions and (3, 2, 4) for orientations
>>> positions, orientations = prims.get_body_coms(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
>>> positions
[[[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]
 [[0. 0. 0.]
  [0. 0. 0.]]]
>>> orientations
[[[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]
 [[1. 0. 0. 0.]
  [1. 0. 0. 0.]]]

get_body_disable_gravity(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get whether the rigid bodies of articulations in the view have gravity disabled or not

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body gravity activation of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_body_index(body_name: str) → int

Get a ridig body (link) index in the articulation view given its name

Parameters:

body_name (str) – name of the ridig body to query

Returns:

index of the rigid body in the articulation buffers

Return type:

int

Example:

>>> # get the index of the left finger: panda_leftfinger
>>> prims.get_body_index("panda_leftfinger")
10

get_body_inertias(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get rigid body inertias of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body inertias of articulations in the view. Shape is (M, K, 9).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inertias()
[[[1.2988697e-06  0.0  0.0  0.0  1.6535528e-06  0.0  0.0  0.0  2.0331163e-06]
  [1.8686389e-06  0.0  0.0  0.0  1.4378986e-06  0.0  0.0  0.0  9.0681192e-07]
  ...
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]
>>>
>>> # get finger body inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]
 ...
 [[4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]
  [4.2041304e-10  0.0  0.0  0.0  3.9026365e-10  0.0  0.0  0.0  1.3347495e-10]]]

get_body_inv_inertias(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get rigid body inverse inertias of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body inverse inertias of articulations in the view. Shape is (M, K, 9).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse inertias. Returned shape is (5, 12, 9) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_inertias()
[[[7.6990012e+05  0.0  0.0  0.0  6.0475844e+05  0.0  0.0  0.0  4.9185578e+05]
  [5.3514888e+05  0.0  0.0  0.0  6.9545931e+05  0.0  0.0  0.0  1.1027645e+06]
  ...
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]
>>>
>>> # get finger body inverse inertias: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2, 9)
>>> prims.get_body_inv_inertias(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]
 ...
 [[2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]
  [2.3786132e+09  0.0  0.0  0.0  2.5623703e+09  0.0  0.0  0.0  7.4920422e+09]]]

get_body_inv_masses(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get rigid body inverse masses of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body inverse masses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body inverse masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_inv_masses()
[[ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]
 [ 0.35534042  0.42372888  0.42025304  0.37737525  0.3710848  0.33542618  0.8860687
   2.4673615  10. 1.7910539  71.14793  71.14793]]
>>>
>>> # get finger body inverse masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_inv_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[71.14793 71.14793]
 [71.14793 71.14793]
 [71.14793 71.14793]]

get_body_masses(

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get rigid body masses of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to query. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

rigid body masses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all body masses. Returned shape is (5, 12) for the example: 5 envs, 12 rigid bodies
>>> prims.get_body_masses()
[[2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]
 [2.8142028  2.3599997  2.3795187  2.6498823  2.6948018  2.981282
  1.1285807  0.40529126 0.1  0.5583305  0.01405522 0.01405522]]
>>>
>>> # get finger body masses: panda_leftfinger (10) and panda_rightfinger (11)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_body_masses(indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))
[[0.01405522 0.01405522]
 [0.01405522 0.01405522]
 [0.01405522 0.01405522]]

get_coriolis_and_centrifugal_forces(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the Coriolis and centrifugal forces (joint DOF forces required to counteract Coriolis and centrifugal forces for the given articulation state) of articulations in the view

Search for Coriolis and Centrifugal Forces in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs for fixed-based arituclations and K <= num of dofs + 6 for floating-based articulations. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

Coriolis and centrifugal forces of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all coriolis and centrifugal forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs for a fixed-based articulation
>>> prims.get_coriolis_and_centrifugal_forces()
[[ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842561e-06 -1.8269687e-04  5.2162375e-07 -9.7677454e-05  3.0365084e-07
   6.7375931e-06  6.1106007e-08 -4.6237533e-06 -4.1627954e-06]
 [ 1.6842524e-06 -1.8269569e-04  5.2162073e-07 -9.7677548e-05  3.0365106e-07
   6.7375149e-06  6.1105780e-08 -4.6237556e-06 -4.1627968e-06]]
>>>
>>> # get finger joint coriolis and centrifugal forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_coriolis_and_centrifugal_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[-4.6237556e-06 -4.1627968e-06]
 [-4.6237533e-06 -4.1627954e-06]
 [-4.6237556e-06 -4.1627968e-06]]

get_default_state() → XFormPrimViewState

Get the default states (positions and orientations) defined with the set_default_state method

Returns:

returns the default state of the prims that is used after each reset.

Return type:

XFormPrimViewState

Example:

>>> state = prims.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimViewState object at 0x7f82f73e3070>
>>> state.positions
[[ 1.5  -0.75  0.  ]
 [ 1.5   0.75  0.  ]
 [ 0.   -0.75  0.  ]
 [ 0.    0.75  0.  ]
 [-1.5  -0.75  0.  ]]
>>> state.orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]

get_dof_index(dof_name: str) → int

Get a DOF index in the joint buffers given its name

Parameters:

dof_name (str) – name of the joint that corresponds to the degree of freedom to query

Returns:

index of the degree of freedom in the joint buffers

Return type:

int

Example:

>>> # get the index of the left finger joint: panda_finger_joint1
>>> prims.get_dof_index("panda_finger_joint1")
7

get_dof_limits() → ndarray | Tensor

Get the articulations DOFs limits (lower and upper)

Returns:

degrees of freedom position limits. Shape is (N, num_dof, 2). For the last dimension, index 0 corresponds to lower limits and index 1 corresponds to upper limits

Return type:

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # get DOF limits. Returned shape is (5, 9, 2) for the example: 5 envs, 9 DOFs
>>> prims.get_dof_limits()
[[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]
...
[[-2.8973  2.8973]
 [-1.7628  1.7628]
 [-2.8973  2.8973]
 [-3.0718 -0.0698]
 [-2.8973  2.8973]
 [-0.0175  3.7525]
 [-2.8973  2.8973]
 [ 0.      0.04  ]
 [ 0.      0.04  ]]]

get_dof_types(

dof_names: List[str] | None = None,

) → List[str]

Get the DOF types given the DOF names

Parameters:

dof_names (List[str], optional) – names of the joints that corresponds to the degrees of freedom to query. Defaults to None.

Returns:

types of the joints that corresponds to the degrees of freedom. Types can be invalid, translation or rotation.

Return type:

List[str]

Example:

>>> # get all DOF types
>>> prims.get_dof_types()
[<DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Rotation: 0>, <DofType.Rotation: 0>,
 <DofType.Rotation: 0>, <DofType.Translation: 1>, <DofType.Translation: 1>]
>>>
>>> # get only the finger DOF types: panda_finger_joint1 and panda_finger_joint2
>>> prims.get_dof_types(dof_names=["panda_finger_joint1", "panda_finger_joint2"])
[<DofType.Translation: 1>, <DofType.Translation: 1>]

get_drive_types() → ndarray | Tensor

Get the articulations DOFs limits (lower and upper)

Returns:

degrees of freedom position limits. Shape is (N, num_dof). For the last dimension, index 0 corresponds to lower limits and index 1 corresponds to upper limits

Return type:

Union[np.ndarray, torch.Tensor, wp.array]

get_effort_modes(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → List[str]

Get effort modes for articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Returns:

Returns a List of size (M, K) indicating the effort modes: acceleration or force

Return type:

List

Example:

>>> # get the effort mode for all joints
>>> prims.get_effort_modes()
[['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration'],
 ['acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration', 'acceleration']]
>>>
>>> # get only the finger joints effort modes for the first, middle and last of the 5 envs
>>> prims.get_effort_modes(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[['acceleration', 'acceleration'], ['acceleration', 'acceleration'], ['acceleration', 'acceleration']]

get_enabled_self_collisions(

indices: ndarray | List | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get the enable self collisions flag (physxArticulation:enabledSelfCollisions) for all articulations

Parameters:

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

self collisions flags (boolean interpreted as int). shape (M,)

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all self collisions flags. Returned shape is (5,) for the example: 5 envs
>>> prims.get_enabled_self_collisions()
[0 0 0 0 0]
>>>
>>> # get the self collisions flags for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_enabled_self_collisions(indices=np.array([0, 2, 4]))
[0 0 0]

get_fixed_tendon_dampings(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the dampings of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon dampings of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_dampings()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]

get_fixed_tendon_limit_stiffnesses(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the limit stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limit stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limit_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]

get_fixed_tendon_limits(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the limits of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon stiffnesses of articulations in the view. Shape is (M, K, 2).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon limits
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_limits()
[[[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]
 [[-0.001  0.001] [-0.001  0.001] [-0.001  0.001] [-0.001  0.001]]]

get_fixed_tendon_offsets(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the offsets of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon offsets
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_offsets()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]

get_fixed_tendon_rest_lengths(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the rest length of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon rest lengths
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_rest_lengths()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]

get_fixed_tendon_stiffnesses(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the stiffness of fixed tendons for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

fixed tendon stiffnesses of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the fixed tendon stiffnesses
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> prims.get_fixed_tendon_stiffnesses()
[[0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]
 [0. 0. 0. 0.]]

get_friction_coefficients(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.array

Get the friction coefficients for the articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint friction coefficients for articulations in the view. shape (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get joint friction coefficients. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_friction_coefficients()
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_friction_coefficients(indices=np.array([0,2,4]), joint_indices=np.array([7,8]))
[[0. 0.]
 [0. 0.]
 [0. 0.]]

get_gains(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → Tuple[ndarray | Tensor, ndarray | Tensor, warp.indexedarray | warp.index]

Get the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return clones of the internal buffers. Otherwise False. Defaults to True.

Returns:

stiffness and damping of articulations in the view respectively. shapes are (M, K).

Return type:

Tuple[Union[np.ndarray, torch.Tensor], Union[np.ndarray, torch.Tensor], Union[wp.indexedarray, wp.index]]

Example:

>>> # get all joint stiffness and damping. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> stiffnesses, dampings = prims.get_gains()
>>> stiffnesses
[[60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]
 [60000. 60000. 60000. 60000. 25000. 15000.  5000.  6000.  6000.]]
>>> dampings
[[3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]
 [3000. 3000. 3000. 3000. 3000. 3000. 3000. 1000. 1000.]]
>>>
>>> # get finger joints stiffness and damping: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> stiffnesses, dampings = prims.get_gains(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
>>> stiffnesses
[[6000. 6000.]
 [6000. 6000.]
 [6000. 6000.]]
>>> dampings
[[1000. 1000.]
 [1000. 1000.]
 [1000. 1000.]]

get_generalized_gravity_forces(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the generalized gravity forces (joint DOF forces required to counteract gravitational forces for the given articulation pose) of articulations in the view

Search for Generalized Gravity Force in PhysX docs for more details

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs for fixed-based arituclations and K <= num of dofs + 6 for floating-based articulations. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

generalized gravity forces of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>>

>>> # get all generalized gravity forces. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_generalized_gravity_forces()
[[ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438585e-08 -6.90830994e+00 -1.08778477e-05  1.91585541e+01  5.14090061e-06
   1.18674052e+00  8.02161412e-06  5.18786255e-03 -5.18784765e-03]
 [ 1.32438602e-08 -6.90832138e+00 -1.08629465e-05  1.91585541e+01  5.13810664e-06
   1.18674076e+00  8.01788883e-06  5.18786255e-03 -5.18784765e-03]]
>>>
>>> # get finger joint generalized gravity forces: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_generalized_gravity_forces(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]
 [ 0.00518786 -0.00518785]]

get_jacobian_shape() → ndarray | Tensor | warp.array

Get the Jacobian matrix shape of a single articulation

The Jacobian matrix maps the joint space velocities of a DOF to it’s cartesian and angular velocities

The shape of the Jacobian depends on the number of links (rigid bodies), DOFs, and whether the articulation base is fixed (e.g., robotic manipulators) or not (e.g,. mobile robots).

• Fixed articulation base: (num_bodies - 1, 6, num_dof)

• Non-fixed articulation base: (num_bodies, 6, num_dof + 6)

Each body has 6 values in the Jacobian representing its linear and angular motion along the three coordinate axes. The extra 6 DOFs in the last dimension, for non-fixed base cases, correspond to the linear and angular degrees of freedom of the free root link

Returns:

shape of jacobian for a single articulation.

Return type:

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda (a robotic manipulator with fixed base):
>>> # - num_bodies: 12
>>> # - num_dof: 9
>>> prims.get_jacobian_shape()
(11, 6, 9)

get_jacobians(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the Jacobian matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 3 dimensions are the Jacobian matrix shape. Refer to the get_jacobian_shape method for details about the Jacobian matrix shape

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

Jacobian matrices of articulations in the view. Shape is (M, jacobian_shape).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the Jacobian matrices. Returned shape is (5, 11, 6, 9) for the example: 5 envs, 12 links, 9 DOFs
>>> prims.get_jacobians()
[[[[ 4.2254178e-09  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.2093576e-08  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-6.0873992e-16  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 1.4458647e-07  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01  0.0000000e+00  0.0000000e+00 ...  0.0000000e+00  0.0000000e+00  0.0000000e+00]]
  ...
  [[-4.5089945e-02  8.1210062e-02 -3.8495898e-02 ...  2.8108317e-02  0.0000000e+00 -4.9317405e-02]
   [ 4.2863289e-01  9.7436900e-04  4.0475106e-01 ...  2.4577195e-03  0.0000000e+00  9.9807423e-01]
   [ 6.5973169e-09 -4.2914307e-01 -2.1542320e-02 ...  2.8352857e-02  0.0000000e+00 -3.7625343e-02]
   [ 1.4458647e-07 -1.1999309e-02 -5.3927803e-01 ...  7.0976764e-01  0.0000000e+00  0.0000000e+00]
   [-1.8178657e-10  9.9992776e-01 -6.4710006e-03 ...  8.5178167e-03  0.0000000e+00  0.0000000e+00]
   [ 9.9999976e-01 -3.8743019e-07  8.4210289e-01 ... -7.0438433e-01  0.0000000e+00  0.0000000e+00]]]]

get_joint_index(joint_name: str) → int

Get a joint index in the joint buffers given its name

Parameters:

joint_name (str) – name of the joint that corresponds to the index of the joint in the articulation

Returns:

index of the joint in the joint buffers

Return type:

int

get_joint_max_velocities(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the maximum joint velocities for articulation dofs in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

maximum joint velocities for articulations dofs in the view. shape (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_joint_positions(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the joint positions of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint positions of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint positions. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_positions()
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>>
>>> # get finger joint positions: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_positions(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[0.03991237 0.04      ]
 [0.03991237 0.04      ]
 [0.03991237 0.04      ]]

get_joint_velocities(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the joint velocities of articulations in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint velocities of articulations in the view. Shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint velocities. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_joint_velocities()
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]
>>>
>>> # get finger joint velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_joint_velocities(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[5.4033857e-04 1.0287426e-05]
 [5.4033566e-04 1.0287110e-05]
 [5.4033857e-04 1.0287426e-05]]

get_joints_default_state() → JointsState

Get the default joint states defined with the set_joints_default_state method

Returns:

an object that contains the default joint states

Return type:

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_default_state()
>>> states
<isaacsim.core.utils.types.JointsState object at 0x7fc2c174fd90>
>>> states.positions
[[ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]
 [ 0.   -1.    0.   -2.2   0.    2.4   0.8   0.04  0.04]]
>>> states.velocities
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]
>>> states.efforts
[[0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0. 0. 0. 0.]]

get_joints_state() → JointsState

Get the current joint states (positions and velocities)

Returns:

an object that contains the current joint positions and velocities

Return type:

JointsState

Example:

>>> # returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> states = prims.get_joints_state()
>>> states
<isaacsim.core.utils.types.JointsState object at 0x7fc1a23a82e0>
>>> states.positions
[[ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3220056e-08 -2.8105433e+00  6.8276104e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]
 [ 1.1999921e-02 -5.6962633e-01  1.3219320e-08 -2.8105433e+00  6.8276213e-06
   3.0301569e+00  7.3234755e-01  3.9912373e-02  3.9999999e-02]]
>>> states.velocities
[[ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010074e-06 -7.6763779e-03 -2.1403629e-07  1.1063648e-02 -4.6333400e-05
   3.4824558e-02  8.8469170e-02  5.4033566e-04  1.0287110e-05]
 [ 1.9010375e-06 -7.6763844e-03 -2.1396865e-07  1.1063669e-02 -4.6333633e-05
   3.4824573e-02  8.8469200e-02  5.4033857e-04  1.0287426e-05]]

get_linear_velocities(

indices: ndarray | list | Tensor | warp.array | None = None,

clone=True,

) → ndarray | Tensor | warp.indexedarray

Get the linear velocities of prims in the view.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

linear velocities of the prims in the view. shape is (M, 3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation linear velocities. Returned shape is (5, 3) for the example: 5 envs, linear (3)
>>> prims.get_linear_velocities()
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]
>>>
>>> # get only the articulation linear velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected, linear (3)
>>> prims.get_linear_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]

get_link_index(link_name: str) → int

Get a link index in the link buffers given its name

Parameters:

link_name (str) – name of the link that corresponds to the index of the link in the articulation

Returns:

index of the link in the link buffers

Return type:

int

get_local_poses(

indices: ndarray | list | Tensor | warp.array | None = None,

) → Tuple[ndarray, ndarray] | Tuple[Tensor, Tensor] | Tuple[warp.indexedarray, warp.indexedarray]

Get prim poses in the view with respect to the local frame (the prim’s parent frame).

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

Returns:

first index is positions in the local frame of the prims. shape is (M, 3). Second index is quaternion orientations in the local frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type:

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the local frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_local_poses()
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_local_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]
 [-4.5299529e-08  0.0000000e+00 -2.8610229e-08]
 [ 0.0000000e+00  0.0000000e+00 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]

get_local_scales(

indices: ndarray | list | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get prim scales in the view with respect to the local frame (the parent’s frame).

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

scales applied to the prim’s dimensions in the local frame. shape is (M, 3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the local frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_local_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the local frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_local_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]

get_mass_matrices(

indices: ndarray | List | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the mass matrices of articulations in the view

Note

The first dimension corresponds to the amount of wrapped articulations while the last 2 dimensions are the mass matrix shape. Refer to the get_mass_matrix_shape method for details about the mass matrix shape

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

mass matrices of articulations in the view. Shape is (M, mass_matrix_shape).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the mass matrices. Returned shape is (5, 9, 9) for the example: 5 envs, 9 DOFs for a fixed-based articulation
>>> prims.get_mass_matrices()
[[[ 5.0900602e-01  1.1794259e-06  4.2570841e-01 -1.6387942e-06 -3.1573933e-02
   -1.9736715e-06 -3.1358242e-04 -6.0441834e-03  6.0441834e-03]
  [ 1.1794259e-06  1.0598221e+00  7.4729815e-07 -4.2621672e-01  2.3612277e-08
   -4.9647894e-02 -2.9080724e-07 -1.8432185e-04  1.8432130e-04]
  ...
  [-6.0441834e-03 -1.8432185e-04 -5.7159867e-03  4.0070520e-04  9.6930371e-04
    1.2324301e-04  2.5264668e-10  1.4055224e-02  0.0000000e+00]
  [ 6.0441834e-03  1.8432130e-04  5.7159867e-03 -4.0070404e-04 -9.6930366e-04
   -1.2324269e-04 -3.6906206e-10  0.0000000e+00  1.4055224e-02]]]

get_mass_matrix_shape() → ndarray | Tensor | warp.array

Get the mass matrix shape of a single articulation

The mass matrix contains the generalized mass of the robot depending on the current configuration

The shape of the max matrix depends on the number of DOFs as well as whether the articulation is fixed-base or floating-base. For fixed-base articulation the shape is (num_dof, num_dof) while for floating-base articulation the shape is (num_dof + 6, num_dof + 6)

Returns:

shape of mass matrix for a single articulation.

Return type:

Union[np.ndarray, torch.Tensor, wp.array]

Example:

>>> # for the Franka Panda:
>>> # - num_dof: 9
>>> prims.get_mass_matrix_shape()
(9, 9)
>>> # for Ant robot:
>>> # - num_dof: 8
>>> prims.get_mass_matrix_shape()
    (14, 14)

get_max_efforts(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the maximum efforts for articulation in the view

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (Optional[bool]) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

maximum efforts for articulations in the view. shape (M, K).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all joint maximum efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_max_efforts()
[[5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]
 [5220. 5220. 5220. 5220.  720.  720.  720.  720.  720.]]
>>>
>>> # get finger joint maximum efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_max_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[720. 720.]
 [720. 720.]
 [720. 720.]]

get_measured_joint_efforts(

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Returns the efforts computed/measured by the physics solver of the joint forces in the DOF motion direction

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – joint indices to specify which joints to query. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

computed joint efforts of articulations in the view. shape is (M, K).

Return type:

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint efforts. Returned shape is (5, 9) for the example: 5 envs, 9 DOFs
>>> prims.get_measured_joint_efforts()
[[ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03 -5.1910817e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8254540e-05 -6.9072919e+00  5.3344327e-05  1.9157072e+01 -5.8761045e-05
   1.1863427e+00 -5.6405144e-05  5.1680212e-03 -5.1910840e-03]
 [ 4.8250298e-05 -6.9073005e+00  5.3364405e-05  1.9157070e+01 -5.8759182e-05
   1.1863427e+00 -5.6388220e-05  5.1680300e-03  -5.1910817e-03]]
>>>
>>> # get finger measured joint efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs. Returned shape is (3, 2)
>>> prims.get_measured_joint_efforts(indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))
[[ 0.00516803 -0.00519108]
 [ 0.00516802 -0.00519108]
 [ 0.00516803 -0.00519108]]

get_measured_joint_forces(

indices: ndarray | List | Tensor | None = None,

joint_indices: ndarray | List | Tensor | None = None,

joint_names: List[str] | None = None,

clone: bool = True,

) → ndarray | Tensor

Get the measured joint reaction forces and torques (link incoming joint forces and torques) to external loads

Note

Since the name->index map for joints has not been exposed yet, it is possible to access the joint names and their indices through the articulation metadata.

prims._metadata.joint_names  # list of names
prims._metadata.joint_indices  # dict of name: index

To retrieve a specific row for the link incoming joint force/torque use joint_index + 1

Parameters:

• indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor]], optional) – link indices to specify which link’s incoming joints to query. Shape (K,). Where K <= num of links/bodies. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

joint forces and torques of articulations in the view. Shape is (M, num_joint + 1, 6). Column index 0 is the incoming joint of the base link. For the last dimension the first 3 values are for forces and the last 3 for torques

Return type:

Union[np.ndarray, torch.Tensor]

Example:

>>> # get all measured joint forces and torques. Returned shape is (5, 12, 6) for the example:
>>> # 5 envs, 9 DOFs (but 12 joints including the fixed and root joints)
>>> prims.get_measured_joint_forces()
[[[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]
 ...
 [[ 0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00  0.00000000e+00]
  [ 1.49950760e+02  3.52353277e-06  5.62586996e-04  4.82502983e-05 -6.90729856e+00  2.69259126e-05]
  [-2.60467059e-05 -1.06778236e+02 -6.83844986e+01 -6.90730047e+00 -5.27759657e-05 -1.24897576e-06]
  [ 8.71209946e+01 -4.46646191e-05 -5.57951622e+01  5.33644052e-05 -2.45385647e+01  1.38957939e-05]
  [ 5.18576926e-05 -4.81099091e+01  6.07092705e+01  1.91570702e+01 -5.81023924e-05  1.46875891e-06]
  [-3.16910419e+01  2.31799815e-04  3.99901695e+01 -5.87591821e-05 -1.18634319e+00  2.24427877e-05]
  [-1.07621672e-04  1.53405371e+01 -1.54584875e+01  1.18634272e+00  6.09036942e-05 -1.60679410e-05]
  [-7.54189777e+00 -5.08146524e+00 -5.65130091e+00 -5.63882204e-05  3.88599992e-01 -3.49432468e-01]
  [ 4.74214745e+00 -3.19458222e+00  3.55281782e+00  5.58562024e-05  8.47946014e-03  7.64050474e-03]
  [ 4.07607269e+00  2.16406956e-01 -4.05131817e+00 -5.95658377e-04  1.14070829e-02  2.13965313e-06]
  [ 5.16803004e-03 -9.77545828e-02 -9.70939621e-02 -8.41282599e-12 -1.29066744e-12 -1.93477560e-11]
  [-5.19108167e-03  9.75882635e-02 -9.71064270e-02  8.41282859e-12  1.29066018e-12 -1.93477543e-11]]]
>>>
>>> # get measured joint forces and torques for the fingers for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 2, 6)
>>> metadata = prims._metadata
>>> joint_indices = 1 + np.array([
>>>     metadata.joint_indices["panda_finger_joint1"],
>>>     metadata.joint_indices["panda_finger_joint2"],
>>> ])
>>> joint_indices
[10 11]
>>> prims.get_measured_joint_forces(indices=np.array([0, 2, 4]), joint_indices=joint_indices)
[[[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]
 [[ 5.1680212e-03 -9.7754560e-02 -9.7093947e-02 -8.4141834e-12 -1.2907383e-12 -1.9348209e-11]
  [-5.1910840e-03  9.7588278e-02 -9.7106412e-02  8.4141869e-12  1.2907335e-12 -1.9348207e-11]]
 [[ 5.1680300e-03 -9.7754583e-02 -9.7093962e-02 -8.4128260e-12 -1.2906674e-12 -1.9347756e-11]
  [-5.1910817e-03  9.7588263e-02 -9.7106427e-02  8.4128286e-12  1.2906602e-12 -1.9347754e-11]]]

get_position_residuals(

indices: ndarray | list | Tensor | warp.array | None = None,

report_max: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get physics solver position residuals for articulations. This is the residual across all joints that are part of articulations.

The solver residuals are computed according to impulse variation normalized by the effective mass.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

• report_max (Optional[bool]) – whether to report max or RMS residual. Defaults to True, i.e. max criteria

Returns:

Solver residuals for rigid bodies of the view

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_sleep_thresholds(

indices: ndarray | List | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters:

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

sleep thresholds. shape (M,).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all sleep thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_sleep_thresholds()
[0.005 0.005 0.005 0.005 0.005]
>>>
>>> # get the sleep thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_sleep_thresholds(indices=np.array([0, 2, 4]))
[0.005 0.005 0.005]

get_solver_position_iteration_counts(

indices: ndarray | List | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters:

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

position iteration count. Shape (M,).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all position iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_position_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the position iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_position_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]

get_solver_velocity_iteration_counts(

indices: ndarray | List | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Parameters:

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

velocity iteration count. Shape (M,).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all velocity iteration count. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[32 32 32 32 32]
>>>
>>> # get the velocity iteration count for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[32 32 32]

get_stabilization_thresholds(

indices: ndarray | List | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get the mass-normalized kinetic energy below which the articulations may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters:

indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

stabilization threshold. Shape (M,).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all stabilization thresholds. Returned shape is (5,) for the example: 5 envs
>>> prims.get_solver_velocity_iteration_counts()
[0.001 0.001 0.001 0.001 0.001]
>>>
>>> # get the stabilization thresholds for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_solver_velocity_iteration_counts(indices=np.array([0, 2, 4]))
[0.001 0.001 0.001]

get_velocities(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get the linear and angular velocities of prims in the view.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

Returns:

linear and angular velocities of the prims in the view concatenated. shape is (M, 6). For the last dimension the first 3 values are for linear velocities and the last 3 for angular velocities

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all articulation velocities. Returned shape is (5, 6) for the example: 5 envs, linear (3) and angular (3)
>>> prims.get_velocities()
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]
>>>
>>> # get only the articulation velocities for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 6) for the example: 3 envs selected, linear (3) and angular (3)
>>> prims.get_velocities(indices=np.array([0, 2, 4]))
[[0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]
 [0. 0. 0. 0. 0. 0.]]

get_velocity_residuals(

indices: ndarray | list | Tensor | warp.array | None = None,

report_max: bool = True,

) → ndarray | Tensor | warp.indexedarray

Get physics solver velocity residuals for articulations. This is the residual across all joints that are part of articulations.

The solver residuals are computed according to impulse variation normalized by the effective mass.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view)

• report_max (Optional[bool]) – whether to report max or RMS residual. Defaults to True, i.e. max criteria

Returns:

Solver residuals for rigid bodies of the view

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

get_visibilities(

indices: ndarray | list | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Returns the current visibilities of the prims in stage.

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

Shape (M,) with type bool, where each item holds True

if the prim is visible in stage. False otherwise.

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all visibilities. Returned shape is (5,) for the example: 5 envs
>>> prims.get_visibilities()
[ True  True  True  True  True]
>>>
>>> # get the visibilities for the first, middle and last of the 5 envs. Returned shape is (3,)
>>> prims.get_visibilities(indices=np.array([0, 2, 4]))
[ True  True  True]

get_world_poses(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

usd: bool = True,

) → Tuple[ndarray, ndarray] | Tuple[Tensor, Tensor] | Tuple[warp.indexedarray, warp.indexedarray]

Get the poses of the prims in the view with respect to the world’s frame.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

• usd (bool, optional) – True to query from usd. Otherwise False to query from Fabric data. Defaults to True.

Returns:

first index is positions in the world frame of the prims. shape is (M, 3). Second index is quaternion orientations in the world frame of the prims. Quaternion is scalar-first (w, x, y, z). shape is (M, 4).

Return type:

Union[Tuple[np.ndarray, np.ndarray], Tuple[torch.Tensor, torch.Tensor], Tuple[wp.indexedarray, wp.indexedarray]]

Example:

>>> # get all articulation poses with respect to the world's frame.
>>> # Returned shape is position (5, 3) and orientation (5, 4) for the example: 5 envs
>>> positions, orientations = prims.get_world_poses()
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [ 1.5000000e+00  7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08  7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]
>>>
>>> # get only the articulation poses with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is position (3, 3) and orientation (3, 4) for the example: 3 envs selected
>>> positions, orientations = prims.get_world_poses(indices=np.array([0, 2, 4]))
>>> positions
[[ 1.5000000e+00 -7.5000000e-01 -2.8610229e-08]
 [-4.5299529e-08 -7.5000000e-01 -2.8610229e-08]
 [-1.5000000e+00 -7.5000000e-01 -2.8610229e-08]]
>>> orientations
[[1. 0. 0. 0.]
 [1. 0. 0. 0.]
 [1. 0. 0. 0.]]

get_world_scales(

indices: ndarray | list | Tensor | warp.array | None = None,

) → ndarray | Tensor | warp.indexedarray

Get prim scales in the view with respect to the world’s frame

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

scales applied to the prim’s dimensions in the world frame. shape is (M, 3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get all prims scales with respect to the world's frame.
>>> # Returned shape is (5, 3) for the example: 5 envs
>>> prims.get_world_scales()
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]
>>>
>>> # get only the prims scales with respect to the world's frame for the first, middle and last of the 5 envs.
>>> # Returned shape is (3, 3) for the example: 3 envs selected
>>> prims.get_world_scales(indices=np.array([0, 2, 4]))
[[1. 1. 1.]
 [1. 1. 1.]
 [1. 1. 1.]]

initialize(

physics_sim_view: omni.physics.tensors.SimulationView | None = None,

) → None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

For this particular class, calling this method will do nothing

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()

property initialized: bool

Check if prim view is initialized

Returns:

True if the view object was initialized (after the first call of .initialize()). False otherwise.

Return type:

bool

Example:

>>> # given an initialized articulation view
>>> prims.initialized
True

property is_non_root_articulation_link: bool

Returns: bool: True if the prim corresponds to a non root link in an articulation. Otherwise False.

is_physics_handle_valid() → bool

Check if articulation view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns:

False if .initialize() needs to be called again for the physics handle to be valid. Otherwise True

Return type:

bool

Example:

>>> prims.is_physics_handle_valid()
True

is_valid(

indices: ndarray | list | Tensor | warp.array | None = None,

) → bool

Check that all prims have a valid USD Prim

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

True if all prim paths specified in the view correspond to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> prims.is_valid()
True

is_visual_material_applied(

indices: ndarray | list | Tensor | warp.array | None = None,

) → List[bool]

Check if there is a visual material applied

Parameters:

indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Returns:

True if there is a visual material applied is applied to the corresponding prim in the view. False otherwise.

Return type:

List[bool]

Example:

>>> # given a visual material that is applied only to the first and the last environment
>>> prims.is_visual_material_applied()
[True, False, False, False, True]
>>>
>>> # check for the first, middle and last of the 5 envs
>>> prims.is_visual_material_applied(indices=np.array([0, 2, 4]))
[True, False, True]

property joint_names: List[str]

List of prim names for each joint of the articulations

Returns:

ordered names of joints that corresponds to degrees of freedom for the articulations in the view

Return type:

List[str]

property name: str

Returns: str: name given to the prims view when instantiating it.

property num_bodies: int

Number of rigid bodies (links) of the articulations

Returns:

maximum number of rigid bodies for the articulations in the view

Return type:

int

Example:

>>> prims.num_bodies
12

property num_dof: int

Number of DOF of the articulations

Returns:

maximum number of DOFs for the articulations in the view

Return type:

int

Example:

>>> prims.num_dof
9

property num_fixed_tendons: int

Number of fixed tendons of the articulations

Returns:

maximum number of fixed tendons for the articulations in the view

Return type:

int

Example:

>>> prims.num_fixed_tendons
0

property num_joints: int

Number of joints of the articulations

Returns:

number of joints of the articulations in the view

Return type:

int

property num_shapes: int

Number of rigid shapes of the articulations

Returns:

maximum number of rigid shapes for the articulations in the view

Return type:

int

Example:

>>> prims.num_shapes
17

pause_motion() → None

Pauses the motion of all articulations wrapped under the Articulation.

property prim_paths: List[str]

Returns:

list of prim paths in the stage encapsulated in this view.

Return type:

List[str]

Example:

>>> prims.prim_paths
['/World/envs/env_0', '/World/envs/env_1', '/World/envs/env_2', '/World/envs/env_3', '/World/envs/env_4']

property prims: List[pxr.Usd.Prim]

Returns:

List of USD Prim objects encapsulated in this view.

Return type:

List[Usd.Prim]

Example:

>>> prims.prims
[Usd.Prim(</World/envs/env_0>), Usd.Prim(</World/envs/env_1>), Usd.Prim(</World/envs/env_2>),
 Usd.Prim(</World/envs/env_3>), Usd.Prim(</World/envs/env_4>)]

resume_motion()

Resumes the motion of all articulations wrapped under the Articulation using the position and velocity dof targets cached when pause_motion was called.

set_angular_velocities(

velocities: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set the angular velocities of the prims in the view

The method does this through the physx API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters:

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – angular velocities to set the rigid prims to. shape is (M, 3).

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (0.1, 0.1, 0.1)
>>> velocities = np.full((num_envs, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.full((3, 3), fill_value=0.1)
>>> prims.set_angular_velocities(velocities, indices=np.array([0, 2, 4]))

set_armatures(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set armatures for articulation joints in the view

Search for “Joint Armature” in PhysX docs for more details.

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – armatures for articulation joints in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint armatures to 0.05 for all envs
>>> prims.set_armatures(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) armatures
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_armatures(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))

set_body_coms(

positions: ndarray | Tensor | warp.array | None = None,

orientations: ndarray | Tensor | warp.array | None = None,

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set body center of mass (COM) positions and orientations for articulation bodies in the view.

Parameters:

• positions (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass positions for articulations in the view. shape (M, K, 3).

• orientations (Union[np.ndarray, torch.Tensor, wp.array]) – body center of mass orientations for articulations in the view. shape (M, K, 4).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the center of mass for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (num_envs, prims.num_bodies, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_coms(positions, orientations)
>>>
>>> # set the fingers center of mass: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.01, 0.02, 0.03]), (3, 2, 1))
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 2, 1))
>>> prims.set_body_coms(positions, orientations, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))

set_body_disable_gravity(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set body gravity activation articulation bodies in the view.

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – body gravity activation for articulations in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

set_body_inertias(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set body inertias for articulation bodies in the view.

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – body inertias for articulations in the view. shape (M, K, 9).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the inertias for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the inertias are repeated 5 times
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (num_envs, prims.num_bodies, 1))
>>> prims.set_body_inertias(inertias)
>>>
>>> # set the fingers inertias: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> inertias = np.tile(np.array([0.1, 0.0, 0.0, 0.0, 0.1, 0.0, 0.0, 0.0, 0.1]), (3, 2, 1))
>>> prims.set_body_inertias(inertias, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))

set_body_masses(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

body_indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set body masses for articulation bodies in the view

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – body masses for articulations in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• body_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – body indices to specify which bodies to manipulate. Shape (K,). Where K <= num of bodies. Defaults to None (i.e: all bodies).

Example:

>>> # set the masses for all the articulation rigid bodies to the indicated values.
>>> # Since there are 5 envs, the masses are repeated 5 times
>>> masses = np.tile(np.array([1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.2]), (num_envs, 1))
>>> prims.set_body_masses(masses)
>>>
>>> # set the fingers masses: panda_leftfinger (10) and panda_rightfinger (11) to 0.2
>>> # for the first, middle and last of the 5 envs
>>> masses = np.tile(np.array([0.2, 0.2]), (3, 1))
>>> prims.set_body_masses(masses, indices=np.array([0, 2, 4]), body_indices=np.array([10, 11]))

set_default_state(

positions: ndarray | Tensor | warp.array | None = None,

orientations: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set the default state of the prims (positions and orientations), that will be used after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

• orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # configure default states for all prims
>>> positions = np.zeros((num_envs, 3))
>>> positions[:, 0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_default_state(positions=positions, orientations=orientations)
>>>
>>> # set default states during post-reset
>>> prims.post_reset()

set_effort_modes(

mode: str,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | None = None,

joint_names: List[str] | None = None,

) → None

Set effort modes for articulations in the view

Parameters:

• mode (str) – effort mode to be applied to prims in the view: acceleration or force.

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the effort mode for all joints to 'force'
>>> prims.set_effort_modes("force")
>>>
>>> # set only the finger joints effort mode to 'force' for the first, middle and last of the 5 envs
>>> prims.set_effort_modes("force", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_enabled_self_collisions(

flags: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set the enable self collisions flag (physxArticulation:enabledSelfCollisions)

Parameters:

• flags (Union[np.ndarray, torch.Tensor, wp.array]) – true to enable self collision. otherwise false. shape (M,)

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # enable the self collisions flag for all envs
>>> prims.set_enabled_self_collisions(np.full((num_envs,), True))
>>>
>>> # enable the self collisions flag only for the first, middle and last of the 5 envs
>>> prims.set_enabled_self_collisions(np.full((3,), True), indices=np.array([0, 2, 4]))

set_fixed_tendon_properties(

stiffnesses: ndarray | Tensor | warp.array | None = None,

dampings: ndarray | Tensor | warp.array | None = None,

limit_stiffnesses: ndarray | Tensor | warp.array | None = None,

limits: ndarray | Tensor | warp.array | None = None,

rest_lengths: ndarray | Tensor | warp.array | None = None,

offsets: ndarray | Tensor | warp.array | None = None,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set fixed tendon properties for articulations in the view

Search for Fixed Tendon in PhysX docs for more details

Parameters:

• stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon stiffnesses for articulations in the view. shape (M, K).

• dampings (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon dampings for articulations in the view. shape (M, K).

• limit_stiffnesses (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limit stiffnesses for articulations in the view. shape (M, K).

• limits (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon limits for articulations in the view. shape (M, K, 2).

• rest_lengths (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon rest lengths for articulations in the view. shape (M, K).

• offsets (Union[np.ndarray, torch.Tensor, wp.array]) – fixed tendon offsets for articulations in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the limit stiffnesses and dampings
>>> # for the ShadowHand articulation that has 4 fixed tendons (prims.num_fixed_tendons)
>>> limit_stiffnesses = np.full((num_envs, prims.num_fixed_tendons), fill_value=10.0)
>>> dampings = np.full((num_envs, prims.num_fixed_tendons), fill_value=0.1)
>>> prims.set_fixed_tendon_properties(dampings=dampings, limit_stiffnesses=limit_stiffnesses)

set_friction_coefficients(

values: ndarray | Tensor,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the friction coefficients for articulation joints in the view

Search for “Joint Friction Coefficient” in PhysX docs for more details.

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – friction coefficients for articulation joints in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set all joint friction coefficients to 0.05 for all envs
>>> prims.set_friction_coefficients(np.full((num_envs, prims.num_dof), 0.05))
>>>
>>> # set only the finger joint (panda_finger_joint1 (7) and panda_finger_joint2 (8)) friction coefficients
>>> # for the first, middle and last of the 5 envs to 0.05
>>> prims.set_friction_coefficients(np.full((3, 2), 0.05), indices=np.array([0,2,4]), joint_indices=np.array([7,8]))

set_gains(

kps: ndarray | Tensor | warp.array | None = None,

kds: ndarray | Tensor | warp.array | None = None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

save_to_usd: bool = False,

) → None

Set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings) of articulations in the view

Parameters:

• kps (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – stiffness of the drives. shape is (M, K). Defaults to None.

• kds (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – damping of the drives. shape is (M, K).. Defaults to None.

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• save_to_usd (bool, optional) – True to save the gains in the usd. otherwise False.

Example:

>>> # set the gains (stiffnesses and dampings) for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the gains are repeated 5 times
>>> stiffnesses = np.tile(np.array([100000, 100000, 100000, 100000, 80000, 80000, 80000, 50000, 50000]), (num_envs, 1))
>>> dampings = np.tile(np.array([8000, 8000, 8000, 8000, 5000, 5000, 5000, 2000, 2000]), (num_envs, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings)
>>>
>>> # set the fingers gains (stiffnesses and dampings): panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # to 50000 and 2000 respectively for the first, middle and last of the 5 envs
>>> stiffnesses = np.tile(np.array([50000, 50000]), (3, 1))
>>> dampings = np.tile(np.array([2000, 2000]), (3, 1))
>>> prims.set_gains(kps=stiffnesses, kds=dampings, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joint_efforts(

efforts: ndarray | Tensor | warp.array | None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the joint efforts of articulations in the view

Note

This method can be used for effort control. For this purpose, there must be no joint drive or the stiffness and damping must be set to zero.

Parameters:

• efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – efforts of articulations in the view to be set to in the next frame. shape is (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> efforts = np.tile(np.array([10, 20, 30, 40, 50, 60, 70, 80, 90]), (num_envs, 1))
>>> prims.set_joint_efforts(efforts)
>>>
>>> # set the fingers efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 10
>>> # for the first, middle and last of the 5 envs
>>> efforts = np.tile(np.array([10, 10]), (3, 1))
>>> prims.set_joint_efforts(efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joint_position_targets(

positions: ndarray | Tensor | warp.array | None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the joint position targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters:

• positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint position targets for the implicit PD controller. shape is (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

• For position control, set relatively high stiffness and low damping (to reduce vibrations)

Example:

>>> # apply the target positions (to move all the robot joints) to the indicated values.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_position_targets(positions)
>>>
>>> # close the robot fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_position_targets(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joint_positions(

positions: ndarray | Tensor | warp.array | None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the joint positions of articulations in the view

Warning

This method will immediately set (teleport) the affected joints to the indicated value. Use the set_joint_position_targets or the apply_action methods to control the articulation joints.

Parameters:

• positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint positions of articulations in the view to be set to in the next frame. shape is (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set all the articulation joints.
>>> # Since there are 5 envs, the joint positions are repeated 5 times
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joint_positions(positions)
>>>
>>> # set only the fingers in closed position: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 0.0
>>> # for the first, middle and last of the 5 envs
>>> positions = np.tile(np.array([0.0, 0.0]), (3, 1))
>>> prims.set_joint_positions(positions, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joint_velocities(

velocities: ndarray | Tensor | warp.array | None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the joint velocities of articulations in the view

Warning

This method will immediately set the affected joints to the indicated value. Use the set_joint_velocity_targets or the apply_action methods to control the articulation joints.

Parameters:

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocities of articulations in the view to be set to in the next frame. shape is (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

This method belongs to the methods used to set the articulation kinematic states:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set the velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocities(velocities)
>>>
>>> # set the fingers velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -0.1
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocities(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joint_velocity_targets(

velocities: ndarray | Tensor | warp.array | None,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set the joint velocity targets for the implicit Proportional-Derivative (PD) controllers

Note

This is an independent method for controlling joints. To apply multiple targets (position, velocity, and/or effort) in the same call, consider using the apply_action method

Parameters:

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – joint velocity targets for the implicit PD controller. shape is (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Hint

High stiffness makes the joints snap faster and harder to the desired target, and higher damping smoothes but also slows down the joint’s movement to target

• For velocity control, stiffness must be set to zero with a non-zero damping

Example:

>>> # apply the target velocities for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint velocities are repeated 5 times
>>> velocities = np.tile(np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]), (num_envs, 1))
>>> prims.set_joint_velocity_targets(velocities)
>>>
>>> # apply the fingers target velocities: panda_finger_joint1 (7) and panda_finger_joint2 (8) to -1.0
>>> # for the first, middle and last of the 5 envs
>>> velocities = np.tile(np.array([-0.1, -0.1]), (3, 1))
>>> prims.set_joint_velocity_targets(velocities, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_joints_default_state(

positions: ndarray | Tensor | warp.array | None = None,

velocities: ndarray | Tensor | warp.array | None = None,

efforts: ndarray | Tensor | warp.array | None = None,

) → None

Set the joints default state (joint positions, velocities and efforts) to be applied after each reset.

Note

The default states will be set during post-reset (e.g., calling .post_reset() or world.reset() methods)

Parameters:

• positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint positions. shape is (N, num of dofs). Defaults to None.

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint velocities. shape is (N, num of dofs). Defaults to None.

• efforts (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – default joint efforts. shape is (N, num of dofs). Defaults to None.

Example:

>>> # configure default joint states for all articulations
>>> positions = np.tile(np.array([0.0, -1.0, 0.0, -2.2, 0.0, 2.4, 0.8, 0.04, 0.04]), (num_envs, 1))
>>> prims.set_joints_default_state(
...     positions=positions,
...     velocities=np.zeros((num_envs, prims.num_dof)),
...     efforts=np.zeros((num_envs, prims.num_dof))
... )
>>>
>>> # set default states during post-reset
>>> prims.post_reset()

set_linear_velocities(

velocities: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set the linear velocities of the prims in the view

The method does this through the PhysX API only. It has to be called after initialization. Note: This method is not supported for the gpu pipeline. set_velocities method should be used instead.

Warning

This method will immediately set the articulation state

Parameters:

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear velocities to set the rigid prims to. shape is (M, 3).

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1.0, 1.0, 1.0)
>>> velocities = np.ones((num_envs, 3))
>>> prims.set_linear_velocities(velocities)
>>>
>>> # set only the articulation linear velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 3))
>>> prims.set_linear_velocities(velocities, indices=np.array([0, 2, 4]))

set_local_poses(

translations: ndarray | Tensor | warp.array | None = None,

orientations: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set prim poses in the view with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters:

• translations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – translations in the local frame of the prims (with respect to its parent prim). shape is (M, 3). Defaults to None, which means left unchanged.

• orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the local frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_local_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_local_poses(positions, orientations, indices=np.array([0, 2, 4]))

set_local_scales(

scales: ndarray | Tensor | warp.array | None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set prim scales in the view with respect to the local frame (the prim’s parent frame)

Parameters:

• scales (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – scales to be applied to the prim’s dimensions in the view. shape is (M, 3).

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the scale for all prims. Since there are 5 envs, the scale is repeated 5 times
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (num_envs, 1))
>>> prims.set_local_scales(scales)
>>>
>>> # set the scale for the first, middle and last of the 5 envs
>>> scales = np.tile(np.array([1.0, 0.75, 0.5]), (3, 1))
>>> prims.set_local_scales(scales, indices=np.array([0, 2, 4]))

set_max_efforts(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set maximum efforts for articulation in the view

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – maximum efforts for articulations in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set the max efforts for all the articulation joints to the indicated values.
>>> # Since there are 5 envs, the joint efforts are repeated 5 times
>>> max_efforts = np.tile(np.array([10000, 9000, 8000, 7000, 6000, 5000, 4000, 1000, 1000]), (num_envs, 1))
>>> prims.set_max_efforts(max_efforts)
>>>
>>> # set the fingers max efforts: panda_finger_joint1 (7) and panda_finger_joint2 (8) to 1000
>>> # for the first, middle and last of the 5 envs
>>> max_efforts = np.tile(np.array([1000, 1000]), (3, 1))
>>> prims.set_max_efforts(max_efforts, indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

set_max_joint_velocities(

values: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Set maximum velocities for articulation in the view

Parameters:

• values (Union[np.ndarray, torch.Tensor, wp.array]) – maximum velocities for articulations in the view. shape (M, K).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

set_sleep_thresholds(

thresholds: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set the threshold for articulations to enter a sleep state

Search for Articulations and Sleeping in PhysX docs for more details

Parameters:

• thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – sleep thresholds to be applied. shape (M,).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the sleep threshold for all envs
>>> prims.set_sleep_thresholds(np.full((num_envs,), 0.01))
>>>
>>> # set only the sleep threshold for the first, middle and last of the 5 envs
>>> prims.set_sleep_thresholds(np.full((3,), 0.01), indices=np.array([0, 2, 4]))

set_solver_position_iteration_counts(

counts: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set the solver (position) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters:

• counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the position iteration count for all envs
>>> prims.set_solver_position_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the position iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_position_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))

set_solver_velocity_iteration_counts(

counts: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set the solver (velocity) iteration count for the articulations

The solver iteration count determines how accurately contacts, drives, and limits are resolved. Search for Solver Iteration Count in PhysX docs for more details.

Warning

Setting a higher number of iterations may improve the fidelity of the simulation, although it may affect its performance.

Parameters:

• counts (Union[np.ndarray, torch.Tensor, wp.array]) – number of iterations for the solver. Shape (M,).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the velocity iteration count for all envs
>>> prims.set_solver_velocity_iteration_counts(np.full((num_envs,), 64))
>>>
>>> # set only the velocity iteration count for the first, middle and last of the 5 envs
>>> prims.set_solver_velocity_iteration_counts(np.full((3,), 64), indices=np.array([0, 2, 4]))

set_stabilization_thresholds(

thresholds: ndarray | Tensor | warp.array,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Set the mass-normalized kinetic energy below which the articulation may participate in stabilization

Search for Stabilization Threshold in PhysX docs for more details

Parameters:

• thresholds (Union[np.ndarray, torch.Tensor, wp.array]) – stabilization thresholds to be applied. Shape (M,).

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set the stabilization threshold for all envs
>>> prims.set_stabilization_thresholds(np.full((num_envs,), 0.005))
>>>
>>> # set only the stabilization threshold for the first, middle and last of the 5 envs
>>> prims.set_stabilization_thresholds(np.full((3,), 0.0051), indices=np.array([0, 2, 4]))

set_velocities(

velocities: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set the linear and angular velocities of the prims in the view at once.

The method does this through the PhysX API only. It has to be called after initialization

Warning

This method will immediately set the articulation state

Parameters:

• velocities (Optional[Union[np.ndarray, torch.Tensor, wp.array]]) – linear and angular velocities respectively to set the rigid prims to. shape is (M, 6).

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Hint

This method belongs to the methods used to set the articulation kinematic state:

set_velocities (set_linear_velocities, set_angular_velocities), set_joint_positions, set_joint_velocities, set_joint_efforts

Example:

>>> # set each articulation linear velocity to (1., 1., 1.) and angular velocity to (.1, .1, .1)
>>> velocities = np.ones((num_envs, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities)
>>>
>>> # set only the articulation velocities for the first, middle and last of the 5 envs
>>> velocities = np.ones((3, 6))
>>> velocities[:,3:] = 0.1
>>> prims.set_velocities(velocities, indices=np.array([0, 2, 4]))

set_visibilities(

visibilities: ndarray | Tensor | warp.array,

indices: ndarray | list | Tensor | warp.array | None = None,

) → None

Set the visibilities of the prims in stage

Parameters:

• visibilities (Union[np.ndarray, torch.Tensor, wp.array]) – flag to set the visibilities of the usd prims in stage. Shape (M,). Where M <= size of the encapsulated prims in the view.

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Defaults to None (i.e: all prims in the view).

Example:

>>> # make all prims not visible in the stage
>>> prims.set_visibilities(visibilities=[False] * num_envs)

set_world_poses(

positions: ndarray | Tensor | warp.array | None = None,

orientations: ndarray | Tensor | warp.array | None = None,

indices: ndarray | list | Tensor | warp.array | None = None,

usd: bool = True,

) → None

Set poses of prims in the view with respect to the world’s frame.

Warning

This method will change (teleport) the prim poses immediately to the indicated value

Parameters:

• positions (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – positions in the world frame of the prim. shape is (M, 3). Defaults to None, which means left unchanged.

• orientations (Optional[Union[np.ndarray, torch.Tensor, wp.array]], optional) – quaternion orientations in the world frame of the prims. quaternion is scalar-first (w, x, y, z). shape is (M, 4). Defaults to None, which means left unchanged.

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• usd (bool, optional) – True to query from usd. Otherwise False to query from Fabric data. Defaults to True.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> # reposition all articulations in row (x-axis)
>>> positions = np.zeros((num_envs, 3))
>>> positions[:,0] = np.arange(num_envs)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (num_envs, 1))
>>> prims.set_world_poses(positions, orientations)
>>>
>>> # reposition only the articulations for the first, middle and last of the 5 envs in column (y-axis)
>>> positions = np.zeros((3, 3))
>>> positions[:,1] = np.arange(3)
>>> orientations = np.tile(np.array([1.0, 0.0, 0.0, 0.0]), (3, 1))
>>> prims.set_world_poses(positions, orientations, indices=np.array([0, 2, 4]))

switch_control_mode(

mode: str,

indices: ndarray | List | Tensor | warp.array | None = None,

joint_indices: ndarray | List | Tensor | warp.array | None = None,

joint_names: List[str] | None = None,

) → None

Switch control mode between "position", "velocity", or "effort" for all joints

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected articulations and joints according to the following rule:

Control mode	Stiffnesses	Dampings
"position"	Kps	Kds
"velocity"	0	Kds
"effort"	0	0

Parameters:

• mode (str) – control mode to switch the articulations specified to. It can be "position", "velocity", or "effort"

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• joint_indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – joint indices to specify which joints to manipulate. Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

• joint_names (Optional[List[str]]) – joint names to specify which joints to manipulate (can’t be sppecified together with joint_indices). Shape (K,). Where K <= num of dofs. Defaults to None (i.e: all dofs).

Example:

>>> # set 'velocity' as control mode for all joints
>>> prims.switch_control_mode("velocity")
>>>
>>> # set 'effort' as control mode only for the fingers: panda_finger_joint1 (7) and panda_finger_joint2 (8)
>>> # for the first, middle and last of the 5 envs
>>> prims.switch_control_mode("effort", indices=np.array([0, 2, 4]), joint_indices=np.array([7, 8]))

switch_dof_control_mode(

mode: str,

dof_index: int,

indices: ndarray | List | Tensor | warp.array | None = None,

) → None

Switch control mode between "position", "velocity", or "effort" for the specified DOF

This method will set the implicit Proportional-Derivative (PD) controller’s Kps (stiffnesses) and Kds (dampings), defined via the set_gains method, of the selected DOF according to the following rule:

Control mode	Stiffnesses	Dampings
"position"	Kps	Kds
"velocity"	0	Kds
"effort"	0	0

Parameters:

• mode (str) – control mode to switch the DOF specified to. It can be "position", "velocity" or "effort"

• dof_index (int) – dof index to switch the control mode of.

• indices (Optional[Union[np.ndarray, List, torch.Tensor, wp.array]], optional) – indices to specify which prims to manipulate. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

Example:

>>> # set 'velocity' as control mode for the panda_joint1 (0) joint for all envs
>>> prims.switch_dof_control_mode("velocity", dof_index=0)
>>>
>>> # set 'effort' as control mode for the panda_joint1 (0) for the first, middle and last of the 5 envs
>>> prims.switch_dof_control_mode("effort", dof_index=0, indices=np.array([0, 2, 4]))

Scenes

class Scene

Bases: object

Provide methods to add objects of interest in the stage to retrieve their information and set their reset default state in an easy way

Example:

>>> from isaacsim.core.api.scenes import Scene
>>>
>>> scene = Scene()
>>> scene
<isaacsim.core.api.scenes.scene.Scene object at 0x...>

property stage: pxr.Usd.Stage

Returns:

current USD stage

Return type:

Usd.Stage

Example:

>>> scene.stage
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x...usd'),
               sessionLayer=Sdf.Find('anon:0x...usda'),
               pathResolverContext=<invalid repr>)

add(

obj: SingleXFormPrim,

) → SingleXFormPrim

Add an object to the scene registry

Parameters:

obj (SingleXFormPrim) – object to be added

Raises:

Exception – The object type is not supported yet

Returns:

object

Return type:

SingleXFormPrim

Example:

>>> from isaacsim.core.prims import XFormPrim
>>>
>>> prims = XFormPrim(prim_paths_expr="/World")
>>> scene.add(prims)
<isaacsim.core.prims.XFormPrim object at 0x...>

add_ground_plane(

size: float | None = None,

z_position: float = 0,

name='ground_plane',

prim_path: str = '/World/groundPlane',

static_friction: float = 0.5,

dynamic_friction: float = 0.5,

restitution: float = 0.8,

color: ndarray | None = None,

) → GroundPlane

Create a ground plane and add it to the scene registry

Parameters:

• size (Optional[float], optional) – length of each edge. Defaults to 5000.0.

• z_position (float, optional) – ground plane position in the z-axis. Defaults to 0.

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “ground_plane”.

• prim_path (str, optional) – prim path of the prim to create. Defaults to “/World/groundPlane”.

• static_friction (float, optional) – static friction coefficient. Defaults to 0.5.

• dynamic_friction (float, optional) – dynamic friction coefficient. Defaults to 0.5.

• restitution (float, optional) – restitution coefficient. Defaults to 0.8.

• color (Optional[np.ndarray], optional) – color of the visual plane. Defaults to None, which means 50% gray

Returns:

ground plane instance

Return type:

GroundPlane

Example:

>>> scene.add_ground_plane()
<isaacsim.core.api.objects.ground_plane.GroundPlane object at 0x...>

add_default_ground_plane(

z_position: float = 0,

name='default_ground_plane',

prim_path: str = '/World/defaultGroundPlane',

static_friction: float = 0.5,

dynamic_friction: float = 0.5,

restitution: float = 0.8,

) → GroundPlane

Create a ground plane (using the default asset for Isaac Sim environments) and add it to the scene registry

Parameters:

• z_position (float, optional) – ground plane position in the z-axis. Defaults to 0.

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “default_ground_plane”.

• prim_path (str, optional) – prim path of the prim to create. Defaults to “/World/defaultGroundPlane”.

• static_friction (float, optional) – static friction coefficient. Defaults to 0.5.

• dynamic_friction (float, optional) – dynamic friction coefficient. Defaults to 0.5.

• restitution (float, optional) – restitution coefficient. Defaults to 0.8.

Returns:

ground plane instance

Return type:

GroundPlane

Example:

>>> scene.add_default_ground_plane()
server...
<isaacsim.core.api.objects.ground_plane.GroundPlane object at 0x...>

post_reset() → None

Call the post_reset method on all added objects to the scene registry

Example:

>>> scene.post_reset()

remove_object(name: str, registry_only: bool = False) → None

Remove and object from the scene registry and the USD stage if specified (enable by default)

Parameters:

• name (str) – Name of the prim to be removed.

• registry_only (bool, optional) – True to remove the object from the scene registry only and not the USD. Defaults to False.

Example:

>>> # given a default ground plane named 'default_ground_plane'
>>> scene.remove_object("default_ground_plane")

get_object(

name: str,

) → SingleXFormPrim

Get a registered object by its name if exists otherwise None

Note

Object can be registered via the add method

Parameters:

str (name) – object name

Returns:

object if it exists otherwise None

Return type:

SingleXFormPrim

Example:

>>> # given a default ground plane named 'default_ground_plane'
>>> scene.get_object("default_ground_plane")
<isaacsim.core.api.objects.ground_plane.GroundPlane object at 0x...>

object_exists(name: str) → bool

Check if an object exists in the scene registry

Parameters:

name (str) – object name

Returns:

whether the object exists in the scene registry or not

Return type:

bool

Example:

>>> # given a default ground plane named 'default_ground_plane'
>>> scene.object_exists("default_ground_plane")
True

clear(registry_only: bool = False) → None

Clear the stage from all added objects to the scene registry.

Parameters:

registry_only (bool, optional) – True to remove the object from the scene registry only and not the USD. Defaults to False.

Example:

>>> scene.clear()

compute_object_AABB(

name: str,

) → Tuple[ndarray, ndarray]

Compute the bounding box points (minimum and maximum) of a registered object given its name

Warning

The bounding box computations should be enabled, via the enable_bounding_boxes_computations method, before querying the Axis-Aligned Bounding Box (AABB) of an object

Parameters:

name (str) – object name

Raises:

Exception – If the bounding box computation is not enabled

Returns:

bounding box points (minimum and maximum)

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> scene.enable_bounding_boxes_computations()
>>>
>>> bbox = scene.compute_object_AABB("ground_plane")
>>> bbox[0]  # minimum
array([-50., -50.,  0.])
>>> bbox[1]  # maximum
array([50., 50.,  0.])

enable_bounding_boxes_computations() → None

Enable the bounding boxes computations

Example:

>>> scene.enable_bounding_boxes_computations()

disable_bounding_boxes_computations() → None

Disable the bounding boxes computations

Example:

>>> scene.disable_bounding_boxes_computations()

class SceneRegistry

Bases: object

Class to keep track of the different types of objects added to the scene

Example:

>>> from isaacsim.core.api.scenes import SceneRegistry
>>>
>>> scene_registry = SceneRegistry()
>>> scene_registry
<isaacsim.core.api.scenes.scene_registry.SceneRegistry object at 0x...>

property articulated_systems: dict

Registered SingleArticulation objects

property rigid_objects: dict

Registered SingleRigidPrim objects

property rigid_prim_views: dict

Registered RigidPrim objects

property rigid_contact_views: dict

Registered RigidContactView objects

property geometry_prim_views: dict

Registered GeometryPrim objects

property articulated_views: dict

Registered Articulation objects

property robot_views: dict

Registered RobotView objects

property robots: dict

Registered Robot objects

property xforms: dict

Registered SingleXFormPrim objects

property sensors: dict

Registered BaseSensor (and derived) objects

property xform_prim_views: dict

Registered XFormPrim objects

property deformable_prims: dict

Registered SingleDeformablePrim objects

property deformable_prim_views: dict

Registered DeformablePrim objects

property deformable_materials: dict

Registered DeformableMaterial objects

property deformable_material_views: dict

Registered DeformableMaterialView objects

property cloth_prims: dict

Registered SingleClothPrim objects

property cloth_prim_views: dict

Registered ClothPrim objects

property particle_systems: dict

Registered SingleParticleSystem objects

property particle_system_views: dict

Registered ParticleSystem objects

property particle_materials: dict

Registered ParticleMaterial objects

property particle_material_views: dict

Registered particle_material_view objects

add_rigid_object(

name: str,

rigid_object: SingleRigidPrim,

) → None

Register a SingleRigidPrim (or subclass) object

Parameters:

• name (str) – object name

• rigid_object (SingleRigidPrim) – object

add_rigid_prim_view(

name: str,

rigid_prim_view: RigidPrim,

) → None

Register a RigidPrim (or subclass) object

Parameters:

• name (str) – object name

• rigid_prim_view (RigidPrim) – object

add_rigid_contact_view(

name: str,

rigid_contact_view: RigidContactView,

) → None

Register a RigidContactView (or subclass) object

Parameters:

• name (str) – object name

• rigid_contact_view (RigidContactView) – object

add_articulated_system(

name: str,

articulated_system: SingleArticulation,

) → None

Register a SingleArticulation (or subclass) object

Parameters:

• name (str) – object name

• articulated_system (SingleArticulation) – object

add_articulated_view(

name: str,

articulated_view: Articulation,

) → None

Register a Articulation (or subclass) object

Parameters:

• name (str) – object name

• articulated_view (Articulation) – object

add_geometry_object(

name: str,

geometry_object: SingleGeometryPrim,

) → None

Register a SingleGeometryPrim (or subclass) object

Parameters:

• name (str) – object name

• geometry_object (SingleGeometryPrim) – object

add_geometry_prim_view(

name: str,

geometry_prim_view: GeometryPrim,

) → None

Register a GeometryPrim (or subclass) object

Parameters:

• name (str) – object name

• geometry_prim_view (GeometryPrim) – object

add_robot(

name: str,

robot: Robot,

) → None

Register a Robot (or subclass) object

Parameters:

• name (str) – object name

• robot (Robot) – object

add_robot_view(

name: str,

robot_view: RobotView,

) → None

Register a RobotView (or subclass) object

Parameters:

• name (str) – object name

• robot_view (RobotView) – object

add_xform_view(

name: str,

xform_prim_view: XFormPrim,

) → None

Register a XFormPrim (or subclass) object

Parameters:

• name (str) – object name

• xform_prim_view (XFormPrim) – object

add_deformable(

name: str,

deformable: SingleDeformablePrim,

) → None

Register a SingleDeformablePrim (or subclass) object

Parameters:

• name (str) – object name

• deformable (SingleDeformablePrim) – object

add_deformable_view(

name: str,

deformable_prim_view: DeformablePrim,

) → None

Register a DeformablePrim (or subclass) object

Parameters:

• name (str) – object name

• deformable_prim_view (DeformablePrim) – object

add_deformable_material(

name: str,

deformable_material: DeformableMaterial,

) → None

Register a DeformableMaterial (or subclass) object

Parameters:

• name (str) – object name

• deformable_material (DeformableMaterial) – object

add_deformable_material_view(

name: str,

deformable_material_view: DeformableMaterialView,

) → None

Register a DeformableMaterialView (or subclass) object

Parameters:

• name (str) – object name

• deformable_material_view (DeformableMaterialView) – object

add_cloth(

name: str,

cloth: SingleClothPrim,

) → None

Register a SingleClothPrim (or subclass) object

Parameters:

• name (str) – object name

• cloth (SingleClothPrim) – object

add_cloth_view(

name: str,

cloth_prim_view: ClothPrim,

) → None

Register a ClothPrim (or subclass) object

Parameters:

• name (str) – object name

• cloth_prim_view (ClothPrim) – object

add_particle_system(

name: str,

particle_system: SingleParticleSystem,

) → None

Register a SingleParticleSystem (or subclass) object

Parameters:

• name (str) – object name

• particle_system (ParticleSystem) – object

add_particle_system_view(

name: str,

particle_system_view: ParticleSystem,

) → None

Register a ParticleSystem (or subclass) object

Parameters:

• name (str) – object name

• particle_system_view (ParticleSystem) – object

add_particle_material(

name: str,

particle_material: ParticleMaterial,

) → None

Register a ParticleMaterial (or subclass) object

Parameters:

• name (str) – object name

• particle_material (ParticleMaterial) – object

add_particle_material_view(

name: str,

particle_material_view: ParticleMaterialView,

) → None

Register a ParticleMaterialView (or subclass) object

Parameters:

• name (str) – object name

• particle_material_view (ParticleMaterialView) – object

add_xform(

name: str,

xform: SingleXFormPrim,

) → None

Register a SingleXFormPrim (or subclass) object

Parameters:

• name (str) – object name

• robot (Robot) – object

add_sensor(

name: str,

sensor: BaseSensor,

) → None

Register a BaseSensor (or subclass) object

Parameters:

• name (str) – object name

• sensor (BaseSensor) – object

name_exists(name: str) → bool

Check if an object exists in the registry by its name

Parameters:

name (str) – object name

Returns:

whether the object is registered or not

Return type:

bool

Example:

>>> # given a registered ground plane named 'default_ground_plane'
>>> scene_registry.name_exists("default_ground_plane")
True

remove_object(name: str) → None

Remove and object from the registry

Note

This method will only remove the object from the internal registry. The wrapped object will not be removed from the USD stage

Parameters:

name (str) – object name

Raises:

Exception – If the name doesn’t exist in the registry

Example:

>>> # given a registered ground plane named 'default_ground_plane'
>>> scene_registry.remove_object("default_ground_plane")

get_object(

name: str,

) → SingleXFormPrim

Get a registered object by its name if exists otherwise None

Parameters:

name (str) – object name

Returns:

the object if it exists otherwise None

Return type:

SingleXFormPrim

Example:

>>> # given a registered ground plane named 'default_ground_plane'
>>> scene_registry.get_object("default_ground_plane")
<isaacsim.core.api.objects.ground_plane.GroundPlane object at 0x...>

Sensors

class BaseSensor(

prim_path: str,

name: str = 'base_sensor',

position: Sequence[float] | None = None,

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

scale: Sequence[float] | None = None,

visible: bool | None = None,

)

Bases: SingleXFormPrim

Provides a common properties and methods to deal with prims as a sensor

Note

This class, which inherits from SingleXFormPrim, does not currently add any new property/method to it. Its definition is oriented to future implementations.

Parameters:

• prim_path (str) – prim path of the Prim to encapsulate or create.

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “base_sensor”.

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world/ local frame of the prim (depends if translation or position is specified). quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

• scale (Optional[Sequence[float]], optional) – local scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

• visible (bool, optional) – set to false for an invisible prim in the stage while rendering. Defaults to True.

Raises:

Exception – if translation and position defined at the same time

initialize(physics_sim_view=None) → None

Create a physics simulation view if not passed and using PhysX tensor API

Note

If the prim has been added to the world scene (e.g., world.scene.add(prim)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prim.initialize()

post_reset() → None

Reset the prim to its default state (position and orientation).

Note

For an articulation, in addition to configuring the root prim’s default position and spatial orientation (defined via the set_default_state method), the joint’s positions, velocities, and efforts (defined via the set_joints_default_state method) are imposed

Example:

>>> prim.post_reset()

apply_visual_material(

visual_material: VisualMaterial,

weaker_than_descendants: bool = False,

) → None

Apply visual material to the held prim and optionally its descendants.

Parameters:

• visual_material (VisualMaterial) – visual material to be applied to the held prim. Currently supports PreviewSurface, OmniPBR and OmniGlass.

• weaker_than_descendants (bool, optional) – True if the material shouldn’t override the descendants materials, otherwise False. Defaults to False.

Example:

>>> from isaacsim.core.api.materials import OmniGlass
>>>
>>> # create a dark-red glass visual material
>>> material = OmniGlass(
...     prim_path="/World/material/glass",  # path to the material prim to create
...     ior=1.25,
...     depth=0.001,
...     thin_walled=False,
...     color=np.array([0.5, 0.0, 0.0])
... )
>>> prim.apply_visual_material(material)

get_applied_visual_material() → VisualMaterial

Return the current applied visual material in case it was applied using apply_visual_material or it’s one of the following materials that was already applied before: PreviewSurface, OmniPBR and OmniGlass.

Returns:

the current applied visual material if its type is currently supported.

Return type:

VisualMaterial

Example:

>>> # given a visual material applied
>>> prim.get_applied_visual_material()
<isaacsim.core.api.materials.omni_glass.OmniGlass object at 0x7f36263106a0>

get_default_state() → XFormPrimState

Get the default prim states (spatial position and orientation).

Returns:

an object that contains the default state of the prim (position and orientation)

Return type:

XFormPrimState

Example:

>>> state = prim.get_default_state()
>>> state
<isaacsim.core.utils.types.XFormPrimState object at 0x7f33addda650>
>>>
>>> state.position
[-4.5299529e-08 -1.8347054e-09 -2.8610229e-08]
>>> state.orientation
[1. 0. 0. 0.]

get_local_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the local frame (the prim’s parent frame)

Returns:

first index is the position in the local frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the local frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_local_pose()
>>> position
[0. 0. 0.]
>>> orientation
[0. 0. 0.]

get_local_scale() → ndarray

Get prim’s scale with respect to the local frame (the parent’s frame)

Returns:

scale applied to the prim’s dimensions in the local frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_local_scale()
[1. 1. 1.]

get_visibility() → bool

Returns:

true if the prim is visible in stage. false otherwise.

Return type:

bool

Example:

>>> # get the visible state of an visible prim on the stage
>>> prim.get_visibility()
True

get_world_pose() → Tuple[ndarray, ndarray]

Get prim’s pose with respect to the world’s frame

Returns:

first index is the position in the world frame (with shape (3, )). Second index is quaternion orientation (with shape (4, )) in the world frame

Return type:

Tuple[np.ndarray, np.ndarray]

Example:

>>> # if the prim is in position (1.0, 0.5, 0.0) with respect to the world frame
>>> position, orientation = prim.get_world_pose()
>>> position
[1.  0.5 0. ]
>>> orientation
[1. 0. 0. 0.]

get_world_scale() → ndarray

Get prim’s scale with respect to the world’s frame

Returns:

scale applied to the prim’s dimensions in the world frame. shape is (3, ).

Return type:

np.ndarray

Example:

>>> prim.get_world_scale()
[1. 1. 1.]

is_valid() → bool

Check if the prim path has a valid USD Prim at it

Returns:

True is the current prim path corresponds to a valid prim in stage. False otherwise.

Return type:

bool

Example:

>>> # given an existing and valid prim
>>> prims.is_valid()
True

is_visual_material_applied() → bool

Check if there is a visual material applied

Returns:

True if there is a visual material applied. False otherwise.

Return type:

bool

Example:

>>> # given a visual material applied
>>> prim.is_visual_material_applied()
True

property name: str | None

Returns: str: name given to the prim when instantiating it. Otherwise None.

property non_root_articulation_link: bool

Used to query if the prim is a non root articulation link

Returns:

True if the prim itself is a non root link

Return type:

bool

Example:

>>> # for a wrapped articulation (where the root prim has the Physics Articulation Root property applied)
>>> prim.non_root_articulation_link
False

property prim: pxr.Usd.Prim

Returns: Usd.Prim: USD Prim object that this object holds.

property prim_path: str

Returns: str: prim path in the stage

set_default_state(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set the default state of the prim (position and orientation), that will be used after each reset.

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Example:

>>> # configure default state
>>> prim.set_default_state(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1, 0, 0, 0]))
>>>
>>> # set default states during post-reset
>>> prim.post_reset()

set_local_pose(

translation: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Set prim’s pose with respect to the local frame (the prim’s parent frame).

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• translation (Optional[Sequence[float]], optional) – translation in the local frame of the prim (with respect to its parent prim). shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the local frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_local_pose(translation=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

set_local_scale(

scale: Sequence[float] | None,

) → None

Set prim’s scale with respect to the local frame (the prim’s parent frame).

Parameters:

scale (Optional[Sequence[float]]) – scale to be applied to the prim’s dimensions. shape is (3, ). Defaults to None, which means left unchanged.

Example:

>>> # scale prim 10 times smaller
>>> prim.set_local_scale(np.array([0.1, 0.1, 0.1]))

set_visibility(visible: bool) → None

Set the visibility of the prim in stage

Parameters:

visible (bool) – flag to set the visibility of the usd prim in stage.

Example:

>>> # make prim not visible in the stage
>>> prim.set_visibility(visible=False)

set_world_pose(

position: Sequence[float] | None = None,

orientation: Sequence[float] | None = None,

) → None

Ses prim’s pose with respect to the world’s frame

Warning

This method will change (teleport) the prim pose immediately to the indicated value

Parameters:

• position (Optional[Sequence[float]], optional) – position in the world frame of the prim. shape is (3, ). Defaults to None, which means left unchanged.

• orientation (Optional[Sequence[float]], optional) – quaternion orientation in the world frame of the prim. quaternion is scalar-first (w, x, y, z). shape is (4, ). Defaults to None, which means left unchanged.

Hint

This method belongs to the methods used to set the prim state

Example:

>>> prim.set_world_pose(position=np.array([1.0, 0.5, 0.0]), orientation=np.array([1., 0., 0., 0.]))

class RigidContactView(

prim_paths_expr: str | List[str],

filter_paths_expr: List[str] | List[List[str]],

name: str = 'rigid_contact_view',

prepare_contact_sensors: bool = True,

disable_stablization: bool = True,

max_contact_count: int = 0,

)

Bases: object

Provides high level functions to deal with rigid prims (one or many) that track their contacts through filters as well as their attributes/properties.

This class wraps all matching rigid prims found at the regex provided at the prim_paths_expr argument

Warning

The rigid prim view object must be initialized in order to be able to operate on it. See the initialize method for more details.

Parameters:

• prim_paths_expr (Union[str, List[str]]) – prim paths regex to encapsulate all prims that match it. example: “/World/Env[1-5]/Cube” will match /World/Env1/Cube, /World/Env2/Cube..etc. (a non regex prim path can also be used to encapsulate one rigid prim). Additionally a list of regex can be provided. example [“/World/Env[1-5]/Cube”, “/World/Env[10-19]/Cube”].

• Union[List[str] (filter_paths_expr) – list of prim paths regex to filter the contacts for each corresponding prim_paths_expr. Example: [“/World/envs/env_2/Xform”] will filter the contacts corresponding to the expression passed.

• List[List[str]]] – list of prim paths regex to filter the contacts for each corresponding prim_paths_expr. Example: [“/World/envs/env_2/Xform”] will filter the contacts corresponding to the expression passed.

• name (str, optional) – shortname to be used as a key by Scene class. Note: needs to be unique if the object is added to the Scene. Defaults to “rigid_contact_view”.

• prepare_contact_sensors (bool, Optional) – if rigid prims in the view are not cloned from a prim in a prepared state, (although slow for large number of prims) this ensures that appropriate physics settings are applied on all the prim in the view.

• disable_stablization (bool, optional) – disables the contact stabilization parameter in the physics context

• max_contact_count (int, optional) – maximum number of contact data to report when detailed contact information is needed

Example:

>>> import isaacsim.core.utils.stage as stage_utils
>>> from isaacsim.core.cloner import GridCloner
>>> from isaacsim.core.api.sensors import RigidContactView
>>> from pxr import UsdGeom
>>>
>>> env_zero_path = "/World/envs/env_0"
>>> num_envs = 5
>>>
>>> # clone the environment (num_envs)
>>> cloner = GridCloner(spacing=0)
>>> cloner.define_base_env(env_zero_path)
>>> UsdGeom.Xform.Define(stage_utils.get_current_stage(), env_zero_path)
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform", "Xform")
>>> stage_utils.get_current_stage().DefinePrim(f"{env_zero_path}/Xform/Cube", "Cube")
>>> # position the cubes on top of each other
>>> position_offsets = np.zeros((num_envs, 3))
>>> position_offsets[:, 2] = np.arange(num_envs) * 1.1
>>> env_pos = cloner.clone(
...     source_prim_path=env_zero_path,
...     prim_paths=cloner.generate_paths("/World/envs/env", num_envs),
...     position_offsets=position_offsets
...     copy_from_source=True,
... )
>>>
>>> # wrap the prims
>>> prims = RigidContactView(
...     prim_paths_expr="/World/envs/env.*/Xform",
...     name="RigidContactView_view",
...     filter_paths_expr=["/World/envs/env_2/Xform"],
...     max_contact_count=10,
... )
>>> prims
<isaacsim.core.api.sensors.rigid_contact_view.RigidContactView object at 0x7f8d4eb1abf0>

property num_shapes: int

Returns:

number of rigid shapes for the prims in the view.

Return type:

int

Example:

>>> prims.num_shapes
5

property num_filters: int

Returns:

number of filters bodies that report their contact with the rigid prims.

Return type:

int

Example:

>>> prims.num_filters
1

is_physics_handle_valid() → bool

Check if rigid prim view’s physics handler is initialized

Warning

If the physics handler is not valid many of the methods that requires PhysX will return None.

Returns:

True if the physics handle of the view is valid (i.e physics is initialized for the view). Otherwise False.

Return type:

bool

Example:

>>> prims.is_physics_handle_valid()
True

initialize(

physics_sim_view: omni.physics.tensors.SimulationView | None = None,

) → None

Create a physics simulation view if not passed and set other properties using the PhysX tensor API

Note

If the rigid prim view has been added to the world scene (e.g., world.scene.add(prims)), it will be automatically initialized when the world is reset (e.g., world.reset()).

Warning

This method needs to be called after each hard reset (e.g., Stop + Play on the timeline) before interacting with any other class method.

Parameters:

physics_sim_view (omni.physics.tensors.SimulationView, optional) – current physics simulation view. Defaults to None.

Example:

>>> prims.initialize()

get_net_contact_forces(

indices: ndarray | Tensor | warp.array | None = None,

clone: bool = True,

dt: float = 1.0,

) → ndarray | Tensor | warp.indexedarray

Get the overall net contact forces on the prims in the view with respect to the world’s frame.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

• dt (float) – time step multiplier to convert the underlying impulses to forces. The function returns contact impulses if the default dt is used

Returns:

Net contact forces of the prims with shape (M,3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the net contact force on all rigid bodies. Returned shape is (5, 3).
>>> prims.get_net_contact_forces()
[[ 1.8731881e-03  5.4876995e-03  1.6408131e+02]
 [ 1.9060407e-02 -2.2513291e-02  1.6358723e+02]
 [-2.1011427e-02  3.5647806e-02  1.6371542e+02]
 [ 9.4006478e-05 -9.3258200e-03  1.6348369e+02]
 [ 9.3709816e-05 -9.2963902e-03  1.6296776e+02]]
>>>
>>> # get the net contact force on the rigid bodies for the first, middle and last of the 5 envs
>>> prims.get_net_contact_forces(indices=np.array([0, 2, 4]))
[[ 1.8731881e-03  5.4876995e-03  1.6408131e+02]
 [-2.1011427e-02  3.5647806e-02  1.6371542e+02]
 [ 9.3709816e-05 -9.2963902e-03  1.6296776e+02]]

get_contact_force_matrix(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

dt: float = 1.0,

) → ndarray | Tensor | warp.indexedarray

Get the contact forces between the prims in the view and the filter prims.

E.g., a matrix of dimension (num_shapes, num_filters, 3) where num_filters is determined according to the filter_paths_expr parameter

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

• dt (float) – time step multiplier to convert the underlying impulses to forces. The function returns contact impulses if the default dt is used

Returns:

Net contact forces between the view prim and the filter prims with shape (M, self.num_filters, 3).

Return type:

Union[np.ndarray, torch.Tensor, wp.indexedarray]

Example:

>>> # get the contact forces between the prims and the filter prims (the cube in the middle)
>>> prims.get_contact_force_matrix()
[[[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[ 2.2649009e-02 -1.3710857e-02 -4.9047806e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
 [[-3.3276828e-03 -2.3870371e-02  3.2733777e+02]]
 [[ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]]

get_contact_force_data(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

dt: float = 1.0,

) → Tuple[ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray]

Get more detailed contact information between the prims in the view and the filter prims.

Specifically, this method provides individual contact normals, contact points, contact separations as well as contact forces for each pair (the sum of which equals the forces that the get_contact_force_matrix method provides as the force aggregate of a pair)

Given to the dynamic nature of collision between bodies, this method will provide buffers of contact data which are arranged sequentially for each pair. The starting index and the number of contact data points for each pair in this stream can be realized from pair_contacts_start_indices, and pair_contacts_count tensors. They both have a dimension of (num_shapes, num_filters) where num_filters is determined according to the filter_paths_expr parameter

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indices to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

• dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for normal forces with shape (max_contact_count, 1), points with shape (max_contact_count, 3), normals with shape (max_contact_count, 3), and distances with shape (max_contact_count, 1), as well as two tensors with shape (M, self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

Example:

>>> # get detailed contact force data between the prims and the filter prims (the cube in the middle)
>>> data = prims.get_contact_force_data()
>>> data[0]  # normal forces
[[-168.53815]
 [ -89.57392]
 [-156.10307]
 [ -75.17234]
 [  98.0681 ]
 [  52.56319]
 [ 108.26558]
 [  67.62025]
 [   0.     ]
 [   0.     ]]
>>> data[1]  # points
[[ 0.4948182  -0.49902824  1.5001888 ]
 [ 0.4950411   0.49933064  1.5001996 ]
 [-0.5024581   0.49930018  1.5001924 ]
 [-0.5024276  -0.49880558  1.5001817 ]
 [-0.5023767   0.497138    2.5001519 ]
 [-0.502735   -0.49877006  2.5001822 ]
 [ 0.4947694  -0.4989927   2.500226  ]
 [ 0.4949917   0.49677914  2.5001955 ]
 [ 0.          0.          0.        ]
 [ 0.          0.          0.        ]]
>>> data[2]  # normals
[[-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [-4.3812128e-05  3.0501858e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 2.1408198e-06 -7.0731985e-05  1.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]
 [ 0.0000000e+00  0.0000000e+00  0.0000000e+00]]
>>> data[3]  # distances
[[ 3.7143487e-05]
 [-4.0254322e-06]
 [-4.0531158e-05]
 [ 6.0737699e-07]
 [ 1.9307560e-04]
 [ 9.2272363e-05]
 [ 4.6372414e-05]
 [ 1.4718286e-04]
 [ 0.0000000e+00]
 [ 0.0000000e+00]]
>>> data[4]  # pair contacts count
[[0]
 [4]
 [0]
 [4]
 [0]]
>>> data[5]  # start indices of pair contacts
[[0]
 [0]
 [4]
 [4]
 [8]]

get_friction_data(

indices: ndarray | list | Tensor | warp.array | None = None,

clone: bool = True,

dt: float = 1.0,

) → Tuple[ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray, ndarray | Tensor | warp.indexedarray]

Gets friction data between the prims in the view and the filter prims. Specifically, this method provides frictional contact forces, and points. The data in reported for number of anchor points that includes tangential forces in a single tangent direction to contact normal. Given to the dynamic nature of collision between bodies, this method will provide buffers of friction data arranged sequentially for each pair. The starting index and the number of contact data points for each pair in this stream can be realized from pair_contacts_start_indices, and pair_contacts_count tensors. They both have a dimension of (self.num_shapes, self.num_filters) where filter_count is determined according to the filter_paths_expr parameter.

Parameters:

• indices (Optional[Union[np.ndarray, list, torch.Tensor, wp.array]], optional) – indicies to specify which prims to query. Shape (M,). Where M <= size of the encapsulated prims in the view. Defaults to None (i.e: all prims in the view).

• clone (bool, optional) – True to return a clone of the internal buffer. Otherwise False. Defaults to True.

• dt (float) – time step multiplier to convert the underlying impulses to forces. If the default value is used then the forces are in fact contact impulses

Returns:

Tuple[Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray],

Union[np.ndarray, torch.Tensor, wp.indexedarray], Union[np.ndarray, torch.Tensor, wp.indexedarray]]: A set of buffers for tangential forces per patch (at number of anchor points, each in a single directions) with shape (max_contact_count, 3), points with shape (max_contact_count, 3), as well as two tensors with shape (M, self.num_filters) to indicate the starting index and the number of contact data points per pair in the aforementioned buffers.

Simulation Context

class SimulationContext(*args, **kwargs)

Bases: object

This class provide functions that take care of many time-related events such as perform a physics or a render step for instance. Adding/ removing callback functions that gets triggered with certain events such as a physics step, timeline event (pause or play..etc), stage open/ close..etc.

It also includes an instance of PhysicsContext which takes care of many physics related settings such as setting physics dt, solver type..etc.

Parameters:

• physics_dt (Optional[float], optional) – dt between physics steps. Defaults to None.

• rendering_dt (Optional[float], optional) – dt between rendering steps. Note: rendering means rendering a frame of the current application and not only rendering a frame to the viewports/cameras. So UI elements of Isaac Sim will be refreshed with this dt as well if running non-headless. Defaults to None.

• stage_units_in_meters (Optional[float], optional) – The metric units of assets. This will affect gravity value..etc. Defaults to None.

• physics_prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

• set_defaults (bool, optional) – set to True to use the defaults settings [physics_dt = 1.0/ 60.0, stage units in meters = 0.01 (i.e in cms), rendering_dt = 1.0 / 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

• backend (str, optional) – specifies the backend to be used (numpy or torch or warp). Defaults to numpy.

• device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch or warp backend.

Example:

>>> from isaacsim.core.api import SimulationContext
>>>
>>> simulation_context = SimulationContext()
>>> simulation_context
<isaacsim.core.api.simulation_context.simulation_context.SimulationContext object at 0x...>

classmethod instance() → SimulationContext

Get the instance of the class, if it was instantiated before

Returns:

SimulationContext object or None

Return type:

SimulationContext

Example:

>>> # given that the class has already been instantiated before
>>> simulation_context = SimulationContext.instance()
>>> simulation_context
<isaacsim.core.api.simulation_context.simulation_context.SimulationContext object at 0x...>

classmethod clear_instance() → None

Delete the simulation context object, if it was instantiated before, and destroy any subscribed callback

Example:

>>> SimulationContext.clear_instance()

property app: omni.kit.app.IApp

Returns:

Omniverse Kit Application interface

Return type:

omni.kit.app.IApp

Example:

>>> simulation_context.app
<omni.kit.app._app.IApp object at 0x...>

property current_time_step_index: int

Returns:

current number of physics steps that have elapsed since the simulation was played

Return type:

int

Example:

>>> # given a running Isaac Sim instance and after approximately 15 seconds of physics simulation at 60 Hz
>>> simulation_context.current_time_step_index
911

property current_time: float

Returns:

current time (simulated physical time) that have elapsed since the simulation was played

Return type:

float

Example:

>>> # given a running Isaac Sim instance and after 911 physics steps at 60 Hz
>>> simulation_context.current_time
15.183334125205874

property stage: pxr.Usd.Stage

Returns:

current open USD stage

Return type:

Usd.Stage

Example:

>>> simulation_context.stage
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x...:World....usd'),
               sessionLayer=Sdf.Find('anon:0x...:World...-session.usda'),
               pathResolverContext=<invalid repr>)

property backend: str

Returns:

current backend. Supported backends are: "numpy", "torch" and "warp"

Return type:

str

Example:

>>> simulation_context.backend
numpy

property device: str

Returns:

Device used by the physics context. None for numpy backend

Return type:

str

Example:

>>> simulation_context.device
None

property backend_utils

Get the current backend utils module

Backend	Utils module
"numpy"	isaacsim.core.utils.numpy
"torch"	isaacsim.core.utils.torch
"warp"	isaacsim.core.utils.warp

Returns:

current backend utils module

Return type:

str

Example:

>>> simulation_context.backend_utils
<module 'isaacsim.core.utils.numpy'>

property physics_sim_view

Note

The physics simulation view instance will be only available after initializing the physics (see initialize_physics) or resetting the simulation context (see reset)

Returns:

Physics simulation view instance

Return type:

PhysicsContext

Example:

>>> simulation_context.physics_sim_view
<omni.physics.tensors.impl.api.SimulationView object at 0x...>

get_physics_context() → PhysicsContext

Get the physics context (a class to deal with a physics scene and its settings) instance

Raises:

Exception – if there is no stage currently opened

Returns:

physics context object

Return type:

PhysicsContext

Example:

>>> simulation_context.get_physics_context()
<isaacsim.core.api.physics_context.physics_context.PhysicsContext object at 0x...>

set_simulation_dt(

physics_dt: float | None = None,

rendering_dt: float | None = None,

) → None

Specify the physics step and rendering step size to use when stepping and rendering.

Parameters:

• physics_dt (float) – The physics time-step. None means it won’t change the current setting. (default: None).

• rendering_dt (float) – The rendering time-step. None means it won’t change the current setting. (default: None)

Hint

It is recommended that the two values be divisible, with the rendering_dt being equal to or greater than the physics_dt

Example:

>>> set physics dt to 120 Hz and rendering dt to 60Hz (2 physics steps for each rendering)
>>> simulation_context.set_simulation_dt(physics_dt=1.0 / 120.0, rendering_dt=1.0 / 60.0)

get_physics_dt() → float

Get the current physics dt of the physics context

Raises:

Exception – if there is no stage currently opened

Returns:

current physics dt of the PhysicsContext

Return type:

float

Example:

>>> simulation_context.get_physics_dt()
0.016666666666666666

get_rendering_dt() → float

Get the current rendering dt

Raises:

Exception – if there is no stage currently opened

Returns:

current rendering dt

Return type:

float

Example:

>>> simulation_context.get_rendering_dt()
0.016666666666666666

set_block_on_render(block: bool) → None

Set block on render flag for the simulation thread

Note

This guarantee a one frame lag between any data captured from the render products and the current USD stage if enabled.

Parameters:

block (bool) – True to block the thread until the renderer is done.

Example:

>>> simulation_context.set_block_on_render(False)

get_block_on_render() → bool

Get the block on render flag for the simulation thread

Returns:

True if one frame lag between any data captured from the render products and the current USD stage is guaranteed by blocking the step call.

Return type:

bool

Example:

>>> simulation_context.get_block_on_render()
False

async initialize_simulation_context_async() → None

Initialize the simulation context

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.initialize_simulation_context_async()
...
>>> run_coroutine(task())

initialize_physics() → None

Initialize the physics simulation view

Example:

>>> simulation_context.initialize_physics()

reset(soft: bool = False) → None

Reset the physics simulation view.

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps. For the Extensions workflow use the reset_async method instead

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> simulation_context.reset()

async reset_async(soft: bool = False) → None

Reset the physics simulation view (asynchronous version).

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await simulation_context.reset_async()
>>>
>>> run_coroutine(task())

step(render: bool = True) → None

Steps the physics simulation while rendering or without.

Warning

Calling this method with the render parameter set to True (default value) is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Parameters:

render (bool, optional) – Set to False to only do a physics simulation without rendering. Note: app UI will be frozen (since its not rendering) in this case. Defaults to True.

Raises:

Exception – if there is no stage currently opened

Example:

>>> simulation_context.step()

render() → None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Example:

>>> simulation_context.render()

async render_async() → None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.render_async()
...
>>> run_coroutine(task())

clear() → None

Clear the current stage leaving the PhysicsScene and /World

Example:

>>> simulation_context.clear()

is_simulating() → bool

Check whether the simulation is running or not

Warning

With deprecation of Dynamic Control Toolbox, this function is not needed

It can return True if start_simulation is called even if play was pressed/called.

Returns:

bool” True if physics simulation is happening.

Example:

>>> # given a running simulation
>>> simulation_context.is_simulating()
True

is_playing() → bool

Check whether the simulation is playing

Returns:

True if the simulator is playing.

Return type:

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_playing()
True

is_stopped() → bool

Check whether the simulation is playing

Returns:

True if the simulator is stopped.

Return type:

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_stopped()
False

async play_async() → None

Start playing simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.play_async()
...
>>> run_coroutine(task())

play() → None

Start playing simulation

Note

It does one step internally to propagate all physics handles properly.

Example:

>>> simulation_context.play()

async pause_async() → None

Pause the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.pause_async()
...
>>> run_coroutine(task())

pause() → None

Pause the physics simulation

Example:

>>> simulation_context.pause()

async stop_async() → None

Stop the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.stop_async()
...
>>> run_coroutine(task())

stop() → None

Stop the physics simulation

Example:

>>> simulation_context.stop()

add_physics_callback(

callback_name: str,

callback_fn: Callable[[float], None],

) → None

Add a callback which will be called before each physics step.

callback_fn should take a float argument (e.g., step_size)

Parameters:

• callback_name (str) – should be unique.

• callback_fn (Callable[[float], None]) – [description]

Example:

>>> def callback_physics(step_size):
...     print("physics callback -> step_size:", step_size)
...
>>> simulation_context.add_physics_callback("callback_physics", callback_physics)

remove_physics_callback(callback_name: str) → None

Remove a physics callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.remove_physics_callback("callback_physics")

physics_callback_exists(callback_name: str) → bool

Check if a physics callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.physics_callback_exists("callback_physics")
True

clear_physics_callbacks() → None

Remove all registered physics callbacks

Example:

>>> simulation_context.clear_physics_callbacks()

add_stage_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each stage event such as open/close among others

callback_fn should take an argument of type omni.usd.StageEvent (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable[[omni.usd.StageEvent], None]) – [description]

Example:

>>> def callback_stage(event):
...     print("stage callback -> event:", event)
...
>>> simulation_context.add_stage_callback("callback_stage", callback_stage)

remove_stage_callback(callback_name: str) → None

Remove a stage callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.remove_stage_callback("callback_stage")

stage_callback_exists(callback_name: str) → bool

Check if a stage callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.stage_callback_exists("callback_stage")
True

clear_stage_callbacks() → None

Remove all registered stage callbacks

Example:

>>> simulation_context.clear_stage_callbacks()

add_timeline_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each timeline event such as play/pause.

callback_fn should take an argument of type omni.timeline.TimelineEvent (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable[[omni.timeline.TimelineEvent], None]) – [description]

Example:

>>> def callback_timeline(event):
...     print("timeline callback -> event:", event)
...
>>> simulation_context.add_timeline_callback("callback_timeline", callback_timeline)

remove_timeline_callback(callback_name: str) → None

Remove a timeline callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'timeline'
>>> simulation_context.timeline_callback("timeline")

timeline_callback_exists(callback_name: str) → bool

Check if a timeline callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_timeline'
>>> simulation_context.timeline_callback_exists("callback_timeline")
True

clear_timeline_callbacks() → None

Remove all registered timeline callbacks

Example:

>>> simulation_context.clear_timeline_callbacks()

add_render_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each rendering event such as .render().

callback_fn should take an argument of type (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable) – [description]

Example:

>>> def callback_render(event):
...     print("render callback -> event:", event)
...
>>> simulation_context.add_render_callback("callback_render", callback_render)

remove_render_callback(callback_name: str) → None

Remove a render callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.remove_render_callback("callback_render")

render_callback_exists(callback_name: str) → bool

Check if a render callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.render_callback_exists("callback_render")
True

clear_render_callbacks() → None

Remove all registered render callbacks

Example:

>>> simulation_context.clear_render_callbacks()

clear_all_callbacks() → None

Clear all callbacks which were added using any add_*_callback method

Example:

>>> simulation_context.clear_render_callbacks()

World

class World(*args, **kwargs)

Bases: SimulationContext

This class inherits from SimulationContext which provides the following.

SimulationContext provide functions that take care of many time-related events such as perform a physics or a render step for instance. Adding/ removing callback functions that gets triggered with certain events such as a physics step, timeline event (pause or play..etc), stage open/ close..etc.

It also includes an instance of PhysicsContext which takes care of many physics related settings such as setting physics dt, solver type..etc.

In addition to what is provided from SimulationContext, this class allows the user to add a task to the world and it contains a scene object.

To control the default reset state of different objects easily, the object could be added to a Scene. Besides this, the object is bound to a short keyword that facilitates objects retrievals, like in a dict.

Checkout the required tutorials at https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

Parameters:

• physics_dt (Optional[float], optional) – dt between physics steps. Defaults to None.

• rendering_dt (Optional[float], optional) – dt between rendering steps. Note: rendering means rendering a frame of the current application and not only rendering a frame to the viewports/ cameras. So UI elements of Isaac Sim will be refreshed with this dt as well if running non-headless. Defaults to None.

• stage_units_in_meters (Optional[float], optional) – The metric units of assets. This will affect gravity value..etc. Defaults to None.

• physics_prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.

• set_defaults (bool, optional) – set to True to use the defaults settings [physics_dt = 1.0/ 60.0, stage units in meters = 0.01 (i.e in cms), rendering_dt = 1.0 / 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.

• backend (str, optional) – specifies the backend to be used (numpy or torch or warp). Defaults to numpy.

• device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch or warp backends.

Example:

>>> from isaacsim.core.api import World
>>>
>>> world = World()
>>> world
<isaacsim.core.api.world.world.World object at 0x...>

classmethod clear_instance()

Delete the world object, if it was instantiated before, and destroy any subscribed callback

Example:

>>> World.clear_instance()

property scene: Scene

Returns:

Scene instance

Return type:

Scene

Example:

>>> world.scene
<isaacsim.core.api.scenes.scene.Scene object at 0x>

add_task(

task: BaseTask,

) → None

Add a task to the task registry

Note

Tasks should have a unique name

Parameters:

task (BaseTask) – task object

Example:

>>> from isaacsim.core.api.tasks import BaseTask
>>>
>>> class Task(BaseTask):
...    def get_observations(self):
...        return {'obs': [0]}
...
...    def calculate_metrics(self):
...        return {"reward": 1}
...
...    def is_done(self):
...        return False
...
>>> task = Task(name="custom_task")
>>> world.add_task(task)

is_tasks_scene_built() → bool

Check if the set_up_scene method was called for each registered task

Example:

>>> # given a world instance that was rested at some point
>>> world.is_tasks_scene_built()
True

get_current_tasks() → List[BaseTask]

Get a dictionary of the registered tasks where keys are task names

Returns:

registered tasks

Return type:

List[BaseTask]

Example:

>>> world.get_current_tasks()
{'custom_task': <custom.task.scripts.extension.Task object at 0x...>}

get_task(

name: str,

) → BaseTask

Get a task by its name

Example:

>>> world.get_task("custom_task")
<custom.task.scripts.extension.Task object at 0x...>

get_observations(task_name: str | None = None) → dict

Get observations from all the tasks that were added

Parameters:

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns:

the task (or all tasks) observations

Return type:

dict

Example:

>>> world.get_observations("custom_task")
{'obs': [0]}

calculate_metrics(task_name: str | None = None) → None

Get metrics from all the tasks that were added

Parameters:

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns:

the computed task (or all tasks) metric

Return type:

dict

Example:

>>> world.calculate_metrics("custom_task")
{'reward': 1}

is_done(task_name: str | None = None) → bool

Get done from all the tasks that were added

Parameters:

task_name (Optional[str], optional) – task name to ask for. Defaults to None, which means all the tasks

Returns:

whether the task (or all tasks) is done

Return type:

bool

Example:

>>> world.is_done("custom_task")
False

get_data_logger() → DataLogger

Return the data logger of the world.

Returns:

data logger instance

Return type:

DataLogger

Example:

>>> world.get_data_logger()
<isaacsim.core.api.loggers.data_logger.DataLogger object at 0x...>

initialize_physics() → None

Initialize the physics simulation view and each added object to the Scene

Example:

>>> world.initialize_physics()

reset(soft: bool = False) → None

Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

• All tasks should be added before the first reset is called unless the clear method was called.

• All articulations should be added before the first reset is called unless the clear method was called.

• This method takes care of initializing articulation handles with the first reset called.

• This will do one step internally regardless

• Call post_reset on each object in the Scene

• Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps. For the Extensions workflow use the reset_async method instead

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> world.reset()

async reset_async_set_up_scene(soft: bool = False) → None

Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

• All tasks should be added before the first reset is called unless the clear method was called.

• All articulations should be added before the first reset is called unless the clear method was called.

• This method takes care of initializing articulation handles with the first reset called.

• This will do one step internally regardless

• Call post_reset on each object in the Scene

• Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await world.reset_async_set_up_scene()
>>>
>>> run_coroutine(task())

async reset_async_no_set_up_scene(soft: bool = False) → None

Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

• All tasks should be added before the first reset is called unless the clear method was called.

• All articulations should be added before the first reset is called unless the clear method was called.

• This method takes care of initializing articulation handles with the first reset called.

• This will do one step internally regardless

• Call post_reset on each object in the Scene

• Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
>>>     await world.reset_async_no_set_up_scene()
>>>
>>> run_coroutine(task())

async reset_async(soft: bool = False) → None

Reset the stage to its initial state and each object included in the Scene to its default state

as specified by the set_default_state and __init__ methods

Note

• All tasks should be added before the first reset is called unless the clear method was called.

• All articulations should be added before the first reset is called unless the clear method was called.

• This method takes care of initializing articulation handles with the first reset called.

• This will do one step internally regardless

• Call post_reset on each object in the Scene

• Call post_reset on each Task

Things like setting PD gains for instance should happen at a Task reset or a Robot reset since the defaults are restored after stop method is called.

Parameters:

soft (bool, optional) – if set to True simulation won’t be stopped and start again. It only calls the reset on the scene objects.

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await world.reset_async()
...
>>> run_coroutine(task())

step(render: bool = True, step_sim: bool = True) → None

Step the physics simulation while rendering or without.

Note

The pre_step for each task is called before stepping. This method also update the Bounding Box Cache time for computing bounding box if enabled

Warning

Calling this method with the render parameter set to True (default value) is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Parameters:

• render (bool, optional) – Set to False to only do a physics simulation without rendering. Note: app UI will be frozen (since its not rendering) in this case. Defaults to True.

• step_sim (bool) – True to step simulation (physics and/or rendering)

Example:

>>> world.step()

step_async(step_size: float | None = None) → None

Call all functions that should be called pre stepping the physics

Note

The pre_step for each task is called before stepping. This method also update the Bounding Box Cache time for computing bounding box if enabled

Parameters:

step_size (float) – step size

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await world.step_async()
...
>>> run_coroutine(task())

clear() → None

Clear the current stage leaving the PhysicsScene and /World

Example:

>>> world.clear()

add_physics_callback(

callback_name: str,

callback_fn: Callable[[float], None],

) → None

Add a callback which will be called before each physics step.

callback_fn should take a float argument (e.g., step_size)

Parameters:

• callback_name (str) – should be unique.

• callback_fn (Callable[[float], None]) – [description]

Example:

>>> def callback_physics(step_size):
...     print("physics callback -> step_size:", step_size)
...
>>> simulation_context.add_physics_callback("callback_physics", callback_physics)

add_render_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each rendering event such as .render().

callback_fn should take an argument of type (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable) – [description]

Example:

>>> def callback_render(event):
...     print("render callback -> event:", event)
...
>>> simulation_context.add_render_callback("callback_render", callback_render)

add_stage_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each stage event such as open/close among others

callback_fn should take an argument of type omni.usd.StageEvent (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable[[omni.usd.StageEvent], None]) – [description]

Example:

>>> def callback_stage(event):
...     print("stage callback -> event:", event)
...
>>> simulation_context.add_stage_callback("callback_stage", callback_stage)

add_timeline_callback(

callback_name: str,

callback_fn: Callable,

) → None

Add a callback which will be called after each timeline event such as play/pause.

callback_fn should take an argument of type omni.timeline.TimelineEvent (e.g., event)

Parameters:

• callback_name (str) – [description]

• callback_fn (Callable[[omni.timeline.TimelineEvent], None]) – [description]

Example:

>>> def callback_timeline(event):
...     print("timeline callback -> event:", event)
...
>>> simulation_context.add_timeline_callback("callback_timeline", callback_timeline)

property app: omni.kit.app.IApp

Returns:

Omniverse Kit Application interface

Return type:

omni.kit.app.IApp

Example:

>>> simulation_context.app
<omni.kit.app._app.IApp object at 0x...>

property backend: str

Returns:

current backend. Supported backends are: "numpy", "torch" and "warp"

Return type:

str

Example:

>>> simulation_context.backend
numpy

property backend_utils

Get the current backend utils module

Backend	Utils module
"numpy"	isaacsim.core.utils.numpy
"torch"	isaacsim.core.utils.torch
"warp"	isaacsim.core.utils.warp

Returns:

current backend utils module

Return type:

str

Example:

>>> simulation_context.backend_utils
<module 'isaacsim.core.utils.numpy'>

clear_all_callbacks() → None

Clear all callbacks which were added using any add_*_callback method

Example:

>>> simulation_context.clear_render_callbacks()

clear_physics_callbacks() → None

Remove all registered physics callbacks

Example:

>>> simulation_context.clear_physics_callbacks()

clear_render_callbacks() → None

Remove all registered render callbacks

Example:

>>> simulation_context.clear_render_callbacks()

clear_stage_callbacks() → None

Remove all registered stage callbacks

Example:

>>> simulation_context.clear_stage_callbacks()

clear_timeline_callbacks() → None

Remove all registered timeline callbacks

Example:

>>> simulation_context.clear_timeline_callbacks()

property current_time: float

Returns:

current time (simulated physical time) that have elapsed since the simulation was played

Return type:

float

Example:

>>> # given a running Isaac Sim instance and after 911 physics steps at 60 Hz
>>> simulation_context.current_time
15.183334125205874

property current_time_step_index: int

Returns:

current number of physics steps that have elapsed since the simulation was played

Return type:

int

Example:

>>> # given a running Isaac Sim instance and after approximately 15 seconds of physics simulation at 60 Hz
>>> simulation_context.current_time_step_index
911

property device: str

Returns:

Device used by the physics context. None for numpy backend

Return type:

str

Example:

>>> simulation_context.device
None

get_block_on_render() → bool

Get the block on render flag for the simulation thread

Returns:

True if one frame lag between any data captured from the render products and the current USD stage is guaranteed by blocking the step call.

Return type:

bool

Example:

>>> simulation_context.get_block_on_render()
False

get_physics_context() → PhysicsContext

Get the physics context (a class to deal with a physics scene and its settings) instance

Raises:

Exception – if there is no stage currently opened

Returns:

physics context object

Return type:

PhysicsContext

Example:

>>> simulation_context.get_physics_context()
<isaacsim.core.api.physics_context.physics_context.PhysicsContext object at 0x...>

get_physics_dt() → float

Get the current physics dt of the physics context

Raises:

Exception – if there is no stage currently opened

Returns:

current physics dt of the PhysicsContext

Return type:

float

Example:

>>> simulation_context.get_physics_dt()
0.016666666666666666

get_rendering_dt() → float

Get the current rendering dt

Raises:

Exception – if there is no stage currently opened

Returns:

current rendering dt

Return type:

float

Example:

>>> simulation_context.get_rendering_dt()
0.016666666666666666

async initialize_simulation_context_async() → None

Initialize the simulation context

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.initialize_simulation_context_async()
...
>>> run_coroutine(task())

classmethod instance() → SimulationContext

Get the instance of the class, if it was instantiated before

Returns:

SimulationContext object or None

Return type:

SimulationContext

Example:

>>> # given that the class has already been instantiated before
>>> simulation_context = SimulationContext.instance()
>>> simulation_context
<isaacsim.core.api.simulation_context.simulation_context.SimulationContext object at 0x...>

is_playing() → bool

Check whether the simulation is playing

Returns:

True if the simulator is playing.

Return type:

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_playing()
True

is_simulating() → bool

Check whether the simulation is running or not

Warning

With deprecation of Dynamic Control Toolbox, this function is not needed

It can return True if start_simulation is called even if play was pressed/called.

Returns:

bool” True if physics simulation is happening.

Example:

>>> # given a running simulation
>>> simulation_context.is_simulating()
True

is_stopped() → bool

Check whether the simulation is playing

Returns:

True if the simulator is stopped.

Return type:

bool

Example:

>>> # given a simulation in play
>>> simulation_context.is_stopped()
False

pause() → None

Pause the physics simulation

Example:

>>> simulation_context.pause()

async pause_async() → None

Pause the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.pause_async()
...
>>> run_coroutine(task())

physics_callback_exists(callback_name: str) → bool

Check if a physics callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.physics_callback_exists("callback_physics")
True

property physics_sim_view

Note

The physics simulation view instance will be only available after initializing the physics (see initialize_physics) or resetting the simulation context (see reset)

Returns:

Physics simulation view instance

Return type:

PhysicsContext

Example:

>>> simulation_context.physics_sim_view
<omni.physics.tensors.impl.api.SimulationView object at 0x...>

play() → None

Start playing simulation

Note

It does one step internally to propagate all physics handles properly.

Example:

>>> simulation_context.play()

async play_async() → None

Start playing simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.play_async()
...
>>> run_coroutine(task())

remove_physics_callback(callback_name: str) → None

Remove a physics callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_physics'
>>> simulation_context.remove_physics_callback("callback_physics")

remove_render_callback(callback_name: str) → None

Remove a render callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.remove_render_callback("callback_render")

remove_stage_callback(callback_name: str) → None

Remove a stage callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.remove_stage_callback("callback_stage")

remove_timeline_callback(callback_name: str) → None

Remove a timeline callback by its name

Parameters:

callback_name (str) – callback name

Example:

>>> # given a registered callback named 'timeline'
>>> simulation_context.timeline_callback("timeline")

render() → None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Warning

This method is not intended to be used in the Isaac Sim’s Extensions workflow since the Kit application has the control over the rendering steps

Example:

>>> simulation_context.render()

async render_async() → None

Refresh the Isaac Sim app rendering components including UI elements, viewports and others

Hint

This method is intended to be used in the Isaac Sim’s Extensions workflow where the Kit application has the control over timing of physics and rendering steps

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.render_async()
...
>>> run_coroutine(task())

render_callback_exists(callback_name: str) → bool

Check if a render callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_render'
>>> simulation_context.render_callback_exists("callback_render")
True

set_block_on_render(block: bool) → None

Set block on render flag for the simulation thread

Note

This guarantee a one frame lag between any data captured from the render products and the current USD stage if enabled.

Parameters:

block (bool) – True to block the thread until the renderer is done.

Example:

>>> simulation_context.set_block_on_render(False)

set_simulation_dt(

physics_dt: float | None = None,

rendering_dt: float | None = None,

) → None

Specify the physics step and rendering step size to use when stepping and rendering.

Parameters:

• physics_dt (float) – The physics time-step. None means it won’t change the current setting. (default: None).

• rendering_dt (float) – The rendering time-step. None means it won’t change the current setting. (default: None)

Hint

It is recommended that the two values be divisible, with the rendering_dt being equal to or greater than the physics_dt

Example:

>>> set physics dt to 120 Hz and rendering dt to 60Hz (2 physics steps for each rendering)
>>> simulation_context.set_simulation_dt(physics_dt=1.0 / 120.0, rendering_dt=1.0 / 60.0)

property stage: pxr.Usd.Stage

Returns:

current open USD stage

Return type:

Usd.Stage

Example:

>>> simulation_context.stage
Usd.Stage.Open(rootLayer=Sdf.Find('anon:0x...:World....usd'),
               sessionLayer=Sdf.Find('anon:0x...:World...-session.usda'),
               pathResolverContext=<invalid repr>)

stage_callback_exists(callback_name: str) → bool

Check if a stage callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_stage'
>>> simulation_context.stage_callback_exists("callback_stage")
True

stop() → None

Stop the physics simulation

Example:

>>> simulation_context.stop()

async stop_async() → None

Stop the physics simulation

Example:

>>> from omni.kit.async_engine import run_coroutine
>>>
>>> async def task():
...     await simulation_context.stop_async()
...
>>> run_coroutine(task())

timeline_callback_exists(callback_name: str) → bool

Check if a timeline callback exists

Parameters:

callback_name (str) – callback name

Returns:

whether the callback is registered

Return type:

bool

Example:

>>> # given a registered callback named 'callback_timeline'
>>> simulation_context.timeline_callback_exists("callback_timeline")
True

Tasks

class BaseTask(name: str, offset: ndarray | None = None)

Bases: object

This class provides a way to set up a task in a scene and modularize adding objects to stage, getting observations needed for the behavioral layer, calculating metrics needed about the task, calling certain things pre-stepping, creating multiple tasks at the same time and much more.

Checkout the required tutorials at https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/overview.html

Parameters:

• name (str) – needs to be unique if added to the World.

• offset (Optional[np.ndarray], optional) – offset applied to all assets of the task.

property device

property scene: Scene

Scene of the world

Returns:

[description]

Return type:

Scene

property name: str

[summary]

Returns:

[description]

Return type:

str

set_up_scene(

scene: Scene,

) → None

Adding assets to the stage as well as adding the encapsulated objects such as SingleXFormPrim..etc

to the task_objects happens here.

Parameters:

scene (Scene) – [description]

get_task_objects() → dict

[summary]

Returns:

[description]

Return type:

dict

get_observations() → dict

Returns current observations from the objects needed for the behavioral layer.

Raises:

NotImplementedError – [description]

Returns:

[description]

Return type:

dict

calculate_metrics() → dict

[summary]

Raises:

NotImplementedError – [description]

is_done() → bool

Returns True of the task is done.

Raises:

NotImplementedError – [description]

pre_step(

time_step_index: int,

simulation_time: float,

) → None

called before stepping the physics simulation.

Parameters:

• time_step_index (int) – [description]

• simulation_time (float) – [description]

post_reset() → None

Calls while doing a .reset() on the world.

get_description() → str

[summary]

Returns:

[description]

Return type:

str

cleanup() → None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

set_params(*args, **kwargs) → None

Changes the modifiable parameters of the task

Raises:

NotImplementedError – [description]

get_params() → dict

Gets the parameters of the task.

This is defined differently for each task in order to access the task’s objects and values. Note that this is different from get_observations. Things like the robot name, block name..etc can be defined here for faster retrieval. should have the form of params_representation[“param_name”] = {“value”: param_value, “modifiable”: bool}

Raises:

NotImplementedError – [description]

Returns:

defined parameters of the task.

Return type:

dict

class FollowTarget(

name: str,

target_prim_path: str | None = None,

target_name: str | None = None,

target_position: ndarray | None = None,

target_orientation: ndarray | None = None,

offset: ndarray | None = None,

)

Bases: ABC, BaseTask

[summary]

Parameters:

• name (str) – [description]

• target_prim_path (Optional[str], optional) – [description]. Defaults to None.

• target_name (Optional[str], optional) – [description]. Defaults to None.

• target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

• target_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

• offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

set_up_scene(

scene: Scene,

) → None

[summary]

Parameters:

scene (Scene) – [description]

abstract set_robot() → None

[summary]

Raises:

NotImplementedError – [description]

set_params(

target_prim_path: str | None = None,

target_name: str | None = None,

target_position: ndarray | None = None,

target_orientation: ndarray | None = None,

) → None

[summary]

Parameters:

• target_prim_path (Optional[str], optional) – [description]. Defaults to None.

• target_name (Optional[str], optional) – [description]. Defaults to None.

• target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

• target_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

get_params() → dict

[summary]

Returns:

[description]

Return type:

dict

get_observations() → dict

[summary]

Returns:

[description]

Return type:

dict

calculate_metrics() → dict

[summary]

is_done() → bool

[summary]

target_reached() → bool

[summary]

Returns:

[description]

Return type:

bool

pre_step(

time_step_index: int,

simulation_time: float,

) → None

[summary]

Parameters:

• time_step_index (int) – [description]

• simulation_time (float) – [description]

post_reset() → None

[summary]

add_obstacle(position: ndarray | None = None)

[summary]

Parameters:

position (np.ndarray, optional) – [description]. Defaults to np.array([0.1, 0.1, 1.0]).

remove_obstacle(name: str | None = None) → None

[summary]

Parameters:

name (Optional[str], optional) – [description]. Defaults to None.

get_obstacle_to_delete() → None

[summary]

Returns:

[description]

Return type:

[type]

obstacles_exist() → bool

[summary]

Returns:

[description]

Return type:

bool

cleanup() → None

[summary]

property device

get_description() → str

[summary]

Returns:

[description]

Return type:

str

get_task_objects() → dict

[summary]

Returns:

[description]

Return type:

dict

property name: str

[summary]

Returns:

[description]

Return type:

str

property scene: Scene

Scene of the world

Returns:

[description]

Return type:

Scene

class PickPlace(

name: str,

cube_initial_position: ndarray | None = None,

cube_initial_orientation: ndarray | None = None,

target_position: ndarray | None = None,

cube_size: ndarray | None = None,

offset: ndarray | None = None,

)

Bases: ABC, BaseTask

[summary]

Parameters:

• name (str) – [description]

• cube_initial_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

• cube_initial_orientation (Optional[np.ndarray], optional) – [description]. Defaults to None.

• target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

• cube_size (Optional[np.ndarray], optional) – [description]. Defaults to None.

• offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

set_up_scene(

scene: Scene,

) → None

[summary]

Parameters:

scene (Scene) – [description]

abstract set_robot() → None

set_params(

cube_position: ndarray | None = None,

cube_orientation: ndarray | None = None,

target_position: ndarray | None = None,

) → None

Changes the modifiable parameters of the task

Raises:

NotImplementedError – [description]

get_params() → dict

Gets the parameters of the task.

This is defined differently for each task in order to access the task’s objects and values. Note that this is different from get_observations. Things like the robot name, block name..etc can be defined here for faster retrieval. should have the form of params_representation[“param_name”] = {“value”: param_value, “modifiable”: bool}

Raises:

NotImplementedError – [description]

Returns:

defined parameters of the task.

Return type:

dict

cleanup() → None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

property device

get_description() → str

[summary]

Returns:

[description]

Return type:

str

get_observations() → dict

[summary]

Returns:

[description]

Return type:

dict

get_task_objects() → dict

[summary]

Returns:

[description]

Return type:

dict

property name: str

[summary]

Returns:

[description]

Return type:

str

property scene: Scene

Scene of the world

Returns:

[description]

Return type:

Scene

pre_step(

time_step_index: int,

simulation_time: float,

) → None

[summary]

Parameters:

• time_step_index (int) – [description]

• simulation_time (float) – [description]

post_reset() → None

Calls while doing a .reset() on the world.

calculate_metrics() → dict

[summary]

is_done() → bool

[summary]

class Stacking(

name: str,

cube_initial_positions: ndarray,

cube_initial_orientations: ndarray | None = None,

stack_target_position: ndarray | None = None,

cube_size: ndarray | None = None,

offset: ndarray | None = None,

)

Bases: ABC, BaseTask

[summary]

Parameters:

• name (str) – [description]

• cube_initial_positions (np.ndarray) – [description]

• cube_initial_orientations (Optional[np.ndarray], optional) – [description]. Defaults to None.

• stack_target_position (Optional[np.ndarray], optional) – [description]. Defaults to None.

• cube_size (Optional[np.ndarray], optional) – [description]. Defaults to None.

• offset (Optional[np.ndarray], optional) – [description]. Defaults to None.

set_up_scene(

scene: Scene,

) → None

[summary]

Parameters:

scene (Scene) – [description]

abstract set_robot() → None

[summary]

Raises:

NotImplementedError – [description]

set_params(

cube_name: str | None = None,

cube_position: str | None = None,

cube_orientation: str | None = None,

stack_target_position: str | None = None,

) → None

[summary]

Parameters:

• cube_name (Optional[str], optional) – [description]. Defaults to None.

• cube_position (Optional[str], optional) – [description]. Defaults to None.

• cube_orientation (Optional[str], optional) – [description]. Defaults to None.

• stack_target_position (Optional[str], optional) – [description]. Defaults to None.

get_params() → dict

[summary]

Returns:

[description]

Return type:

dict

get_observations() → dict

[summary]

Returns:

[description]

Return type:

dict

pre_step(

time_step_index: int,

simulation_time: float,

) → None

[summary]

Parameters:

• time_step_index (int) – [description]

• simulation_time (float) – [description]

cleanup() → None

Called before calling a reset() on the world to removed temporary objects that were added during simulation for instance.

property device

get_description() → str

[summary]

Returns:

[description]

Return type:

str

get_task_objects() → dict

[summary]

Returns:

[description]

Return type:

dict

property name: str

[summary]

Returns:

[description]

Return type:

str

post_reset() → None

[summary]

property scene: Scene

Scene of the world

Returns:

[description]

Return type:

Scene

get_cube_names() → List[str]

[summary]

Returns:

[description]

Return type:

List[str]

calculate_metrics() → dict

[summary]

Raises:

NotImplementedError – [description]

Returns:

[description]

Return type:

dict

is_done() → bool

[summary]

Raises:

NotImplementedError – [description]

Returns:

[description]

Return type:

bool