[Question] Best way to add a dummy link

[MinchoU]

Hi. This question might be related to #3668.

What would be the best way to add dummy link that can retrieve the pose using api like asset.data.body_pos_w while not affecting the simulation (i.e., no mass, no collision)? I guess this api can be only used when the target prim has RigidBodyAPI, but it seems like it is hard to remove physical properties in it.

Thanks in advance!

[RandomOakForest]

Thank you for posting this. Have you tried using a prim with the RigidBodyAPI attached but with all physical properties set to minimally impact the simulation? For example,

from omni.isaac.core.utils.prims import define_prim

define_prim(
    "/World/Robot/DummyLink",
    "Xform",
    usd_api=["RigidBodyAPI"],
)
# Set properties via USD attributes
dummy_link = stage.GetPrimAtPath("/World/Robot/DummyLink")
dummy_link.GetAttribute("physxRigidBody:mass").Set(1e-8)
dummy_link.GetAttribute("physxRigidBody:enabledGravity").Set(False)

[MinchoU]

I see. I wondered would there be a cleaner way than this, but I guess that's the only way. Thanks !