Fixed Joint Not Working

Omniverse Isaac Sim
,
1

Hi, I am trying to fix the base of a Panda Robot to a rotating platform in the Simulation. In order to do so, I am using the create_joint function in: Objects connected through fixed joints change orientation after simulation start - #3 by axel.goedrich
The joint has been created, but the Panda Robot does not follow the rotating platform when that one is moving:

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Here you can find the script I am using to create the fixed joint:

    stage = omni.usd.get_context().get_stage()
    
    body0Prim = stage.GetPrimAtPath("/World/Rotating_Stage/Link_YY")
    body1Prim = stage.GetPrimAtPath("/World/Panda/panda_link0")

    cj.createJoint(stage, "Fixed", body0Prim, body1Prim)
    set_drive_parameters(self._rotating_stage.joint1, "position", 90)
    set_drive_parameters(self._rotating_stage.joint2, "position", 0)

I have tried to invert body1Prim and body0Prim relationship as well, but the result is the rotating stage not moving. Disabling and enabling the fixed joint leads to a very fast motion of the rotating stage while the panda arm keeps floating in the air and not following it.

Thank you in advance for your help!

2

Hi,
what you need to do are two things, one is to create the joint between the arm and the platform and second you need to make sure that the arm is not anymore a fixed articulation.
Here check this video:
USD Composer 2023.2.0 Beta - omniverse___content.ov.nvidia.com_Users_aborovicka@nvidia.com_ArticulationJoint.usd_ 2023-08-18 08-49-19.zip (16.1 MB)

Regards,
Ales