Possible bug about Particle System addition

Omniverse Isaac Sim
1

Reproduce:

  1. Open the Isaacsim 2022.2.1.
  2. Stage → World → RightClick → Clear Default prim
  3. Create → Physics → Particle System
  4. No Particle System is added with this error:
2023-10-23 08:05:48 [387,255ms] [Error] [omni.kit.actions.core.python] Error executing PythonAction 'Particle System': ValueError:  is not a valid path

At:
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extscore/omni.usd/omni/usd/_impl/utils.py(944): get_stage_next_free_path
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extsPhysics/omni.physx.ui-104.2.4-5.1/omni/physxui/scripts/menu.py(469): _on_add_particle_system
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extsPhysics/omni.physx.ui-104.2.4-5.1/omni/physxui/scripts/menu.py(162): <lambda>
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extscore/omni.kit.actions.core/omni/kit/actions/core/actions.py(32): execute_action
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extscore/omni.kit.menu.utils/omni/kit/menu/utils/scripts/app_menu.py(283): execute_action
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/python/lib/python3.7/asyncio/events.py(88): _run
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/python/lib/python3.7/asyncio/base_events.py(1786): _run_once
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/python/lib/python3.7/asyncio/base_events.py(541): run_forever
  /home/bong/.local/share/ov/pkg/isaac_sim-2022.2.1/kit/extscore/omni.kit.async_engine/omni/kit/async_engine/async_engine.py(77): _on_update

To solve this issue:

Temporally set World as a default prim, add Particle System, and clear default prim.

2

same issue with Stage → prim_mesh → Add → Physics → Particle Sampler

3

@PARKBONG i am just another OV, so take my input as a grain of salt. if a stage doesn’t include a default prim, you will run into issues bringing the USD into another scene as either a reference or a payload, so i personally like to keep a defaultprim in stage. if you don’t intend to use the USD elsewhere, it may be irrelevant (maybe the mods/devs can confirm for you).

pertaining to the issue you are having with mesh prims, i cannot seem to replicate it in 2022.2.1 (assuming the defaultprim wasn’t cleared already)

CreateParticleSystem

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