I watched the Isaac Sim Office Hours at 11/8.
following the video demo of URDF export from usd and see urdf’s detail.
I found out a error of parent link error miss match.
I use turtlebot3_burger usd at:
As you can see the base_joint’s physics joint the base_joint’s parent is base_footprint.
But exported urdf’s base_joint’s parent is turtlebot3_burger and it also has link.
I removed original’s color materials for compare the difference