How to add a fixed joint Isaac Sim 5.0.0

Omniverse Isaac Sim
1

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Isaac Sim Version

5.1.0
[✔ 5.0.0
4.5.0
4.2.0
4.1.0
4.0.0
4.5.0
2023.1.1
2023.1.0-hotfix.1
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Operating System

Ubuntu 24.04
[✔Ubuntu 22.04
Ubuntu 20.04
Windows 11
Windows 10
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GPU Information

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Topic Description

Detailed Description

(Describe the issue in detail, including what you were trying to do, what you expected to happen, and what actually happened)

Hi, I’m trying to add a fixed joint between my manipulator’s hand and end-effectors on my scene. I only found some scripts and topics for the old version of isaac sim,like( Create a fixed joint through python in Isaac Sim 4.5.0 ), but they didn’t work on Isaac sim 5.0. Could you give me some advise on writing the code on python in order to create or remove a fixed joint? Thanks a lot!!

3

Hi, here’s an example you can run to create a fixed joint in Isaac Sim 5.1:

from omni.isaac.core import SimulationContext
from pxr import Usd, UsdGeom, Gf, UsdPhysics, Sdf, UsdLux, PhysxSchema
import omni

# Initialize simulation
simulation = SimulationContext()
stage = omni.usd.get_context().get_stage()
# The paths to the parent and child prims in your USD stage
parent_prim_path = "/World/Parent"
child_prim_path = "/World/Child"

# Create cube for parent
cube_p = UsdGeom.Cube.Define(stage, parent_prim_path)
cube_p.AddTranslateOp(UsdGeom.XformOp.PrecisionDouble).Set(Gf.Vec3f(0, 0, 0))
cube_p.CreateSizeAttr().Set(0.5)

# Create cube for child
cube_c = UsdGeom.Cube.Define(stage, child_prim_path)
cube_c.AddTranslateOp(UsdGeom.XformOp.PrecisionDouble).Set(Gf.Vec3f(0, 0.6, 0))
cube_c.CreateSizeAttr().Set(0.5)

# Create Fixed Joint
joint_path = "/World/FixedJoint"
usd_joint = UsdPhysics.FixedJoint.Define(stage, joint_path)
usd_joint.CreateBody0Rel().SetTargets([Sdf.Path(parent_prim_path)])
usd_joint.CreateBody1Rel().SetTargets([Sdf.Path(child_prim_path)])
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