isaaclab_newton.sim.spawners

Sub-module for Newton material configuration exports.

Classes

NewtonDeformableBodyMaterialCfg	Newton-specific physics material parameters for volume deformable bodies.
NewtonDeformableMaterialCfg	Newton-specific material properties for a deformable body.
NewtonSurfaceDeformableBodyMaterialCfg	Newton-specific physics material parameters for surface deformable bodies.

Deformable Materials

Newton provides the backend-specific deformable material cfgs. Deformable material spawning is unified in isaaclab.sim.spawners.materials.spawn_deformable_body_material().

class isaaclab_newton.sim.spawners.materials.NewtonDeformableBodyMaterialCfg

Bases: DeformableBodyMaterialBaseCfg, NewtonDeformableMaterialCfg

Newton-specific physics material parameters for volume deformable bodies.

Attributes:

k_mu	First Lame material parameter [Pa].
k_lambda	Second Lame material parameter [Pa].
k_damp	Damping stiffness for tetrahedral elements [Pa*s].
density	The material density [kg/m^3].
particle_radius	Particle radius [m] used by the Newton backend.

k_mu: float

First Lame material parameter [Pa]. Defaults to 1e5 Pa.

k_lambda: float

Second Lame material parameter [Pa]. Defaults to 1e5 Pa.

k_damp: float

Damping stiffness for tetrahedral elements [Pa*s]. Defaults to 0.0.

density: float

The material density [kg/m^3]. Defaults to 1.0 kg/m^3.

particle_radius: float

Particle radius [m] used by the Newton backend.

class isaaclab_newton.sim.spawners.materials.NewtonDeformableMaterialCfg

Bases: object

Newton-specific material properties for a deformable body.

These properties are set with the prefix newton:<property_name>.

Attributes:

density	The material density [kg/m^3].
particle_radius	Particle radius [m] used by the Newton backend.

density: float

The material density [kg/m^3]. Defaults to 1.0 kg/m^3.

particle_radius: float

Particle radius [m] used by the Newton backend.

class isaaclab_newton.sim.spawners.materials.NewtonSurfaceDeformableBodyMaterialCfg

Bases: SurfaceDeformableBodyMaterialBaseCfg, NewtonDeformableMaterialCfg

Newton-specific physics material parameters for surface deformable bodies.

Attributes:

density	The material density [kg/m^3].
particle_radius	Particle radius [m] used by the Newton backend.
tri_ke	Triangle area-preserving stiffness [Pa].
tri_ka	Triangle area stiffness [Pa].
tri_kd	Triangle area damping [Pa*s].
edge_ke	Bending stiffness [N*m].
edge_kd	Bending damping [N*m*s].

density: float

The material density [kg/m^3]. Defaults to 1.0 kg/m^3.

particle_radius: float

Particle radius [m] used by the Newton backend.

tri_ke: float

Triangle area-preserving stiffness [Pa]. Used by Newton backend for cloth meshes.

tri_ka: float

Triangle area stiffness [Pa]. Used by Newton backend for cloth meshes.

tri_kd: float

Triangle area damping [Pa*s]. Used by Newton backend for cloth meshes.

edge_ke: float

Bending stiffness [N*m]. Used by Newton backend for cloth meshes.

edge_kd: float

Bending damping [N*m*s]. Used by Newton backend for cloth meshes.

Newton MPM particle spawner utilities.

Classes

MPMParticleSpawnerCfg	Base configuration for declarative Newton MPM particle generation.
MPMGridCfg	Generate a regular MPM particle lattice inside an axis-aligned local box.
MPMPointsCfg	Generate MPM particles from explicit local-space point positions.
MPMParticleMaterialCfg	Per-particle material values consumed by Newton's implicit MPM solver.

MPM Particles

Declarative particle generation for MPMObject. The spawner creates a placeholder Xform prim; the particles themselves are emitted into the Newton model builder during replication.

class isaaclab_newton.sim.spawners.mpm.MPMParticleSpawnerCfg

Bases: SpawnerCfg

Base configuration for declarative Newton MPM particle generation.

Attributes:

material	Material values applied to generated particles.
visual_color	Display color for Kit particle visualization.
visible	Whether the spawned asset should be visible.
semantic_tags	List of semantic tags to add to the spawned asset.
copy_from_source	Whether to copy the asset from the source prim or inherit it.
spawn_path	Path where the prototype is spawned.
visual_update_frequency	Kit particle visualization update frequency in render frames.

material: MPMParticleMaterialCfg

Material values applied to generated particles.

visual_color: Sequence[float]

Display color for Kit particle visualization.

visible: bool

Whether the spawned asset should be visible. Defaults to True.

semantic_tags: list[tuple[str, str]] | None

List of semantic tags to add to the spawned asset. Defaults to None, which means no semantic tags will be added.

The semantic tags follow the Replicator Semantic tagging system. Each tag is a tuple of the form (type, data), where type is the type of the tag and data is the semantic label associated with the tag. For example, to annotate a spawned asset in the class avocado, the semantic tag would be [("class", "avocado")].

You can specify multiple semantic tags by passing in a list of tags. For example, to annotate a spawned asset in the class avocado and the color green, the semantic tags would be [("class", "avocado"), ("color", "green")].

See also

For more information on the semantics filter, see the documentation for the semantics schema editor.

copy_from_source: bool

Whether to copy the asset from the source prim or inherit it. Defaults to True.

This parameter is only used when cloning prims. If False, then the asset will be inherited from the source prim, i.e. all USD changes to the source prim will be reflected in the cloned prims.

spawn_path: str | None

Path where the prototype is spawned. Defaults to None.

visual_update_frequency: int

Kit particle visualization update frequency in render frames.

class isaaclab_newton.sim.spawners.mpm.MPMGridCfg

Bases: MPMParticleSpawnerCfg

Generate a regular MPM particle lattice inside an axis-aligned local box.

Attributes:

visible	Whether the spawned asset should be visible.
semantic_tags	List of semantic tags to add to the spawned asset.
copy_from_source	Whether to copy the asset from the source prim or inherit it.
spawn_path	Path where the prototype is spawned.
material	Material values applied to generated particles.
visual_color	Display color for Kit particle visualization.
visual_update_frequency	Kit particle visualization update frequency in render frames.
lower	Lower local-space corner of the particle box [m].
upper	Upper local-space corner of the particle box [m].
voxel_size	Target MPM voxel size [m], used with particles_per_cell to choose lattice resolution.
particles_per_cell	Particle lattice density relative to the MPM grid resolution.
jitter	Newton particle-grid jitter value [m].
mass	Per-particle mass [kg].
radius	Particle radius [m].

visible: bool

Whether the spawned asset should be visible. Defaults to True.

semantic_tags: list[tuple[str, str]] | None

List of semantic tags to add to the spawned asset. Defaults to None, which means no semantic tags will be added.

The semantic tags follow the Replicator Semantic tagging system. Each tag is a tuple of the form (type, data), where type is the type of the tag and data is the semantic label associated with the tag. For example, to annotate a spawned asset in the class avocado, the semantic tag would be [("class", "avocado")].

You can specify multiple semantic tags by passing in a list of tags. For example, to annotate a spawned asset in the class avocado and the color green, the semantic tags would be [("class", "avocado"), ("color", "green")].

See also

For more information on the semantics filter, see the documentation for the semantics schema editor.

copy_from_source: bool

Whether to copy the asset from the source prim or inherit it. Defaults to True.

This parameter is only used when cloning prims. If False, then the asset will be inherited from the source prim, i.e. all USD changes to the source prim will be reflected in the cloned prims.

spawn_path: str | None

Path where the prototype is spawned. Defaults to None.

material: MPMParticleMaterialCfg

Material values applied to generated particles.

visual_color: Sequence[float]

Display color for Kit particle visualization.

visual_update_frequency: int

Kit particle visualization update frequency in render frames.

lower: Sequence[float]

Lower local-space corner of the particle box [m].

upper: Sequence[float]

Upper local-space corner of the particle box [m].

voxel_size: float

Target MPM voxel size [m], used with particles_per_cell to choose lattice resolution.

particles_per_cell: float

Particle lattice density relative to the MPM grid resolution.

jitter: float

Newton particle-grid jitter value [m].

mass: float | None

Per-particle mass [kg]. If None, mass is derived from cell volume and material density.

radius: float | None

Particle radius [m]. If None, radius is half the largest generated cell size.

class isaaclab_newton.sim.spawners.mpm.MPMPointsCfg

Bases: MPMParticleSpawnerCfg

Generate MPM particles from explicit local-space point positions.

Attributes:

visible	Whether the spawned asset should be visible.
semantic_tags	List of semantic tags to add to the spawned asset.
copy_from_source	Whether to copy the asset from the source prim or inherit it.
spawn_path	Path where the prototype is spawned.
material	Material values applied to generated particles.
visual_color	Display color for Kit particle visualization.
visual_update_frequency	Kit particle visualization update frequency in render frames.
positions	Local-space particle positions [m].
velocities	Optional local-space particle velocities [m/s].
mass	Particle mass values [kg], either scalar or one value per particle.
radius	Particle radius values [m], either scalar or one value per particle.

visible: bool

Whether the spawned asset should be visible. Defaults to True.

semantic_tags: list[tuple[str, str]] | None

List of semantic tags to add to the spawned asset. Defaults to None, which means no semantic tags will be added.

The semantic tags follow the Replicator Semantic tagging system. Each tag is a tuple of the form (type, data), where type is the type of the tag and data is the semantic label associated with the tag. For example, to annotate a spawned asset in the class avocado, the semantic tag would be [("class", "avocado")].

You can specify multiple semantic tags by passing in a list of tags. For example, to annotate a spawned asset in the class avocado and the color green, the semantic tags would be [("class", "avocado"), ("color", "green")].

See also

For more information on the semantics filter, see the documentation for the semantics schema editor.

copy_from_source: bool

Whether to copy the asset from the source prim or inherit it. Defaults to True.

This parameter is only used when cloning prims. If False, then the asset will be inherited from the source prim, i.e. all USD changes to the source prim will be reflected in the cloned prims.

spawn_path: str | None

Path where the prototype is spawned. Defaults to None.

material: MPMParticleMaterialCfg

Material values applied to generated particles.

visual_color: Sequence[float]

Display color for Kit particle visualization.

visual_update_frequency: int

Kit particle visualization update frequency in render frames.

positions: Sequence[Sequence[float]]

Local-space particle positions [m].

velocities: Sequence[Sequence[float]] | None

Optional local-space particle velocities [m/s]. If None, velocities are zero.

mass: float | Sequence[float]

Particle mass values [kg], either scalar or one value per particle.

radius: float | Sequence[float]

Particle radius values [m], either scalar or one value per particle.

class isaaclab_newton.sim.spawners.mpm.MPMParticleMaterialCfg

Bases: object

Per-particle material values consumed by Newton’s implicit MPM solver.

This is a lightweight value config. It does not create or bind a USD material prim; values are forwarded to Newton as mpm:* custom attributes when particles are added to the model builder.

The defaults model a dry sand-like granular material.

Attributes:

density	Particle material density [kg/m^3], used to derive particle mass when a generator does not override it.
young_modulus	Young's modulus [Pa].
poisson_ratio	Poisson ratio.
viscosity	Viscosity coefficient.
friction	Particle friction coefficient.
damping	Material damping.
yield_pressure	Pressure at which the material yields.
tensile_yield_ratio	Tensile/compressive yield ratio.
yield_stress	Von-Mises yield stress.
hardening	Plastic hardening coefficient.
dilatancy	Granular dilatancy coefficient.

density: float

Particle material density [kg/m^3], used to derive particle mass when a generator does not override it.

young_modulus: float

Young’s modulus [Pa].

poisson_ratio: float

Poisson ratio.

viscosity: float

Viscosity coefficient.

friction: float

Particle friction coefficient.

damping: float

Material damping.

yield_pressure: float

Pressure at which the material yields.

tensile_yield_ratio: float

Tensile/compressive yield ratio.

yield_stress: float

Von-Mises yield stress.

hardening: float

Plastic hardening coefficient.

dilatancy: float

Granular dilatancy coefficient.