How can i import parallel robot in Isaac Sim

I’m trying to import a parallel robot in the Isaac Sim platform. The official docs tells me that I can import a robot model derictly by the URDF files, so I tried this method, and it does well. However, now i need to import a robot containing parallel mechanism. Because of the limit of the URDF files, i cannot generate a urdf file which contains parallel mechanism. Also I cannot find any suggestions in the official docs about how to import the parallel robot. So how can I make it?

Here’s an example of importing a parallel robot structure: Rigging Complex Structures — Omniverse IsaacSim latest documentation

the relevant section is in “breaking the articulation loop section”, where they need to pick a joint and check the “exclude it from Articulation” option in its joint properties.