How to modify restitution coefficient of RigidBodyObject in IsaacLab?

[22421003]

Isaac Sim Version

4.5.0

Operating System

Ubuntu 22.04

GPU Information

• Model: NVIDIA GeForce RTX 4060
• Driver Version: 550.144.03

Topic Description

Detailed Description

I can access and modify restitution coefficient for both terrains and rigid_objects in IsaacGym.
I can do the same things to terrains in IsaacLab too,
but I tried to check many class configuring files in the source category of IsaacLab repository,
still don’t know how to access and modify restitution coefficient of rigid object in IsaacLab.
Can anyone give a help, thank you a lot!

In IsaacGym,

1. as the example code file(IsaacGym/python/examples/body_physics_props.py) shows,
   the restitution attribute of rigid object can be easily accessed via the returned class of function get_actor_rigid_shape_properties() —— isaacgym.gymapi.RigidShapeProperties.
   
   

        # add box actor
        pose = gymapi.Transform()
        pose.p = gymapi.Vec3(0.0, 0.5, 0.0)
        pose.r = gymapi.Quat(0, 2, 2, 1)        # 怎么改变四元数呢?
        box_handle = gym.create_actor(env, asset_box, pose, "actor1", i, 0) # actor 创建的时候要制定位置和姿态
        actor_handles.append(box_handle)

        # set restitution for box actor
        shape_props = gym.get_actor_rigid_shape_properties(env, box_handle)
        shape_props[0].restitution = 1.0
        shape_props[0].compliance = 0.5
        gym.set_actor_rigid_shape_properties(env, box_handle, shape_props)

        # add capsule actor
        pose.p = gymapi.Vec3(0.0, 2.0, 0.0)
        capsule_handle = gym.create_actor(env, asset_capsule, pose, "actor2", i, 0)

2. the restitution exponent of a terrain can also be modified with class isaacgym.gymapi.PlaneParams
   
   
   
   
   
   
   
   

In IsaacLab, similarly, the restitution attribute of terrain, which is often configured by RigidBodyMaterialCfg can be accessed.

members of isaaclab.sim.spawners.materials.RigidBodyMaterialCfg

An example is as follows:

    terrain = TerrainImporterCfg(
        prim_path="/World/ground",
        terrain_type="plane",
        collision_group=-1,
        physics_material=sim_utils.RigidBodyMaterialCfg(
            friction_combine_mode="average",
            restitution_combine_mode="average",
            # friction coefficient
            static_friction=1.0, 
            dynamic_friction=1.0,
            # elastic coefficient
            restitution=0.0,
        ),
        debug_vis=False,
    )

However, I didn’t found that how to access the restitution attribute of a rigid_body or articulation.

members of isaaclab.assets.RigidObject

members of isaaclab.assets.RigidObjectCfg

members of isaaclab.sim.spawners.SpawnerCfg

members of isaaclab.sim.spawners.RigidObjectSpawnerCfg

members of isaaclab.sim.spawners.from_files.UsdFileCfg

An example(IsaacLab/scripts/tutorials/01_assets/run_rigid_object.py) is as follows:

    cone_cfg = RigidObjectCfg(
        prim_path="/World/Origin.*/Cone",
        spawn=sim_utils.ConeCfg(
            radius=0.1,
            height=0.2,
            rigid_props=sim_utils.RigidBodyPropertiesCfg(),
            mass_props=sim_utils.MassPropertiesCfg(mass=1.0),
            collision_props=sim_utils.CollisionPropertiesCfg(),
            visual_material=sim_utils.PreviewSurfaceCfg(diffuse_color=(0.0, 1.0, 0.0), metallic=0.2),
        ),
        init_state=RigidObjectCfg.InitialStateCfg(),
    )
    cone_object = RigidObject(cfg=cone_cfg)

I can’t figure out how to modify the restitution coefficient of rigid object in the code example