Getting an error when loading an extension in Isaac Sim 2023.1.0

[fshahri1]

Hi,
I created an extension using Generate Extension Templates > Loaded Scenario Template. I did not change anything afterward. When I load the extension, I get the following error:

2023-10-22 21:06:59 [171,823ms] [Error] [asyncio] Task exception was never retrieved
future: <Task finished name='Task-385' coro=<LoadButton._on_clicked_fn_wrapper.<locals>._on_click_async() done, defined at /home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.ui/omni/isaac/ui/element_wrappers/core_connectors/ui_core_connectors.py:177> exception=AttributeError("'NoneType' object has no attribute 'warm_start'")>
Traceback (most recent call last):
  File "/home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.ui/omni/isaac/ui/element_wrappers/core_connectors/ui_core_connectors.py", line 194, in _on_click_async
    await world.reset_async()
  File "/home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 359, in reset_async
    await self.reset_async_no_set_up_scene(soft=soft)
  File "/home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 331, in reset_async_no_set_up_scene
    await SimulationContext.reset_async(self, soft=soft)
  File "/home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 426, in reset_async
    await self.play_async()
  File "/home/fahim/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 548, in play_async
    self.get_physics_context().warm_start()
AttributeError: 'NoneType' object has no attribute 'warm_start'

This only happens in version 2023.1.0 and not in version 2022.2.1. Any help is appreciated.

System info:
Ubuntu 22.04.3,
Nvidia 3070 GPU,
Driver Version: 535.104.05 CUDA Version: 12.2

[Simplychenable]

@fshahri1 i am just another OV user, what does the extension manager show after you enabled it? do you mind posting a screenshot?

also, do you mind elaborate what you meant by ‘load the extension’, are you referring to enabling the extension in the extension manager, or actually hitting the ‘load’ button from the template?

[jimlin]

I also encounter this issue, after pressing “Load” button will raise this error.

2023-10-23 10:08:19 [43,427ms] [Error] [asyncio] Task exception was never retrieved
future: <Task finished name='Task-584' coro=<LoadButton._on_clicked_fn_wrapper.<locals>._on_click_async() done, defined at /home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.ui/omni/isaac/ui/element_wrappers/core_connectors/ui_core_connectors.py:177> exception=AttributeError("'NoneType' object has no attribute 'warm_start'")>
Traceback (most recent call last):
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.ui/omni/isaac/ui/element_wrappers/core_connectors/ui_core_connectors.py", line 194, in _on_click_async
    await world.reset_async()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 359, in reset_async
    await self.reset_async_no_set_up_scene(soft=soft)
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 331, in reset_async_no_set_up_scene
    await SimulationContext.reset_async(self, soft=soft)
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 426, in reset_async
    await self.play_async()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 548, in play_async
    self.get_physics_context().warm_start()
AttributeError: 'NoneType' object has no attribute 'warm_start'

Also i found that it will have similar error when I load my usd through Hello World example. When i hit “Load” will output this:

2023-10-23 10:24:25 [23,195ms] [Error] [asyncio] Task exception was never retrieved
future: <Task finished name='Task-565' coro=<BaseSampleExtension._on_load_world.<locals>._on_load_world_async() done, defined at /home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample_extension.py:152> exception=Exception("The Physics Context's physics scene path is invalid, you need to reinit Physics Context")>
Traceback (most recent call last):
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample_extension.py", line 153, in _on_load_world_async
    await self._sample.load_world_async()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample.py", line 47, in load_world_async
    await self._world.reset_async()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 359, in reset_async
    await self.reset_async_no_set_up_scene(soft=soft)
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/world/world.py", line 331, in reset_async_no_set_up_scene
    await SimulationContext.reset_async(self, soft=soft)
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 426, in reset_async
    await self.play_async()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/simulation_context/simulation_context.py", line 548, in play_async
    self.get_physics_context().warm_start()
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/physics_context/physics_context.py", line 250, in warm_start
    self._physx_interface.update_simulation(self.get_physics_dt(), 0.0)
  File "/home/user/.local/share/ov/pkg/isaac_sim-2023.1.0/exts/omni.isaac.core/omni/isaac/core/physics_context/physics_context.py", line 306, in get_physics_dt
    raise Exception("The Physics Context's physics scene path is invalid, you need to reinit Physics Context")
Exception: The Physics Context's physics scene path is invalid, you need to reinit Physics Context

[dan.sandberg]

get_physics_context() is returning None. Does it work if you hit “Play” in the simulator before hitting load? Cause perhaps hitting play will cause a physics context to exist.

[fshahri1]

Hi Dan,
Hitting “Play” before “Load” does not seem to do anything. The same error is produced when “Load” is clicked after “Play”.

[dan.sandberg]

I get the same error, so it’s not your setup.

[arudich]

I believe that this issue is resolved in the imminent hot fix coming out very soon.

[TUMYI]

This bug seems to be fixed in 2023.1.1