Environment:
-
**OS:** Ubuntu Linux
-
**Isaac Sim:** 4.5.0 (installed via
pip install 'isaacsim[all]' --extra-index-url ``https://pypi.nvidia.com) -
**Isaac Lab:** 2.3.0 (cloned from GitHub, checked out to tag
v2.3.0) -
**Conda Environment:**
unitree_rl(Python 3.10) -
**NVIDIA Driver:** 570.195.03
-
**CUDA Version:** 12.8
Issue:
When attempting to run any graphical Isaac Lab demo (e.g., ./isaaclab.sh -p scripts/demos/bipeds.py), the application fails to start and throws a ModuleNotFoundErrorfor omni.kit.usd. The full error traceback is:
[INFO] Using python from: /home/sj/miniconda3/envs/unitree_rl/bin/python
[WARN][AppLauncher]: There are no arguments attached to the ArgumentParser object. If you have your own arguments, please load your own arguments before calling the AppLauncher.add_app_launcher_args method. This allows the method to check the validity of the arguments and perform checks for argument names.
[INFO][AppLauncher]: Using device: cuda:0
[INFO][AppLauncher]: Loading experience file: /home/sj/Desktop/IsaacLab/apps/isaacsim_4_5/isaaclab.python.kit
[Warning] [simulation_app.simulation_app] Modules: [‘omni.kit_app’] were loaded before SimulationApp was started and might not be loaded correctly.
[Warning] [simulation_app.simulation_app] Please check to make sure no extra omniverse or pxr modules are imported before the call to SimulationApp(…)
Loading user config located at: ‘/home/sj/miniconda3/envs/unitree_rl/lib/python3.10/site-packages/omni/data/Kit/Isaac-Sim/4.5/user.config.json’
[Info] [carb] Logging to file: /home/sj/miniconda3/envs/unitree_rl/lib/python3.10/site-packages/omni/logs/Kit/Isaac-Sim/4.5/kit_20251216_170814.log
2025-12-16 09:08:14 [0ms] [Warning] [omni.kit.app.plugin] No crash reporter present, dumps uploading isn’t available.
2025-12-16 09:08:14 [3ms] [Warning] [omni.ext.plugin] [ext: rendering_modes] Extensions config ‘extension.toml’ doesn’t exist ‘/home/sj/Desktop/IsaacLab/apps/isaacsim_4_5/rendering_modes’ or ‘/home/sj/Desktop/IsaacLab/apps/isaacsim_4_5/rendering_modes/config’
[0.058s] Failed to solve some dependencies locally, syncing with extension registry…
2025-12-16 09:08:14 [17ms] [Warning] [omni.ext.plugin] [ext: rendering_modes] Extensions config ‘extension.toml’ doesn’t exist ‘/home/sj/Desktop/IsaacLab/apps/isaacsim_4_5/rendering_modes’ or ‘/home/sj/Desktop/IsaacLab/apps/isaacsim_4_5/rendering_modes/config’
[0.062s] [ext: omni.kit.async_engine-0.0.1] startup
[0.065s] [ext: omni.client.lib-1.0.0] startup
[0.107s] [ext: omni.kit.registry.nucleus-0.0.0] startup
2025-12-16 09:08:16 [1,052ms] [Error] [omni.kit.registry.nucleus.index_v2.index_sync] Syncing registry index failed for url: ‘https://ovextensionsprod.blob.core.windows.net/exts/kit/prod/106/shared/v2’. Exception: Failed to connect to the registry: ‘https://ovextensionsprod.blob.core.windows.net/exts/kit/prod/106/shared/v2’
2025-12-16 09:08:16 [1,812ms] [Error] [omni.kit.registry.nucleus.index_v2.index_sync] Syncing registry index failed for url: ‘https://ovextensionsprod.blob.core.windows.net/exts/kit/prod/sdk/106.5/d02c707b/v2’. Exception: Failed to connect to the registry: ‘https://ovextensionsprod.blob.core.windows.net/exts/kit/prod/sdk/106.5/d02c707b/v2’
2025-12-16 09:08:18 [3,874ms] [Error] [omni.ext.plugin] Failed to resolve extension dependencies. Failure hints:
[isaaclab.python-2.3.0] dependency: ‘omni.kit.menu.edit’ = { version=‘^’ } can’t be satisfied. Available versions:
(none found)
Synced registries:
- kit/default : found 0 packages (couldn’t connect or empty)
- kit/sdk : found 0 packages (couldn’t connect or empty)
- kit/community : found 484 packages
2025-12-16 09:08:18 [3,874ms] [Error] [omni.kit.app.plugin] Exiting app because of dependency solver failure…
Traceback (most recent call last):
File “/home/sj/Desktop/IsaacLab/scripts/demos/bipeds.py”, line 30, in
app_launcher = AppLauncher(args_cli)
File “/home/sj/Desktop/IsaacLab/source/isaaclab/isaaclab/app/app_launcher.py”, line 127, in init
self._create_app()
File “/home/sj/Desktop/IsaacLab/source/isaaclab/isaaclab/app/app_launcher.py”, line 811, in _create_app
self._app = SimulationApp(self._sim_app_config, experience=self._sim_experience_file)
File “/home/sj/miniconda3/envs/unitree_rl/lib/python3.10/site-packages/isaacsim/exts/isaacsim.simulation_app/isaacsim/simulation_app/simulation_app.py”, line 227, in init
from .utils import create_new_stage, open_stage
File “/home/sj/miniconda3/envs/unitree_rl/lib/python3.10/site-packages/isaacsim/exts/isaacsim.simulation_app/isaacsim/simulation_app/utils.py”, line 17, in
from omni.kit.usd import layers
ModuleNotFoundError: No module named ‘omni.kit.usd’
2025-12-16 09:08:18 [3,878ms] [Warning] [carb] Recursive unloadAllPlugins() detected!
**BUT,**Isaac Lab headless training works fine.