I’m trying to load my customized robot (imported from onshape.com and saved as a .usd file) to Isaac Sim by python standalone scripts.
My code is modified from /standalone_examples/api/omni.isaac.core/add_frankas.py.
import os
curr_path = os.path.abspath(os.path.dirname(file))
asset_path = curr_path + “robot/myrobot.usd”
from omni.isaac.kit import SimulationApp
simulation_app = SimulationApp({“headless”: False})
from omni.isaac.core import World
from omni.isaac.core.robots import Robot
from omni.isaac.core.utils.stage import add_reference_to_stage, get_stage_units
import numpy as np
import argparse
import sys
my_world = World(stage_units_in_meters=1.0)
my_world.scene.add_default_ground_plane()
add_reference_to_stage(usd_path=asset_path, prim_path=“/World/myrobot”)
articulated_system_1 = my_world.scene.add(Robot(prim_path=“/World/myrobot”, name=“robot1”))
my_world.reset()
articulated_system_1.set_world_pose(position=np.array([0.0, 0.0, 2.0]) / get_stage_units())
while simulation_app.is_running():
my_world.step(render=True)
simulation_app.close()
But I got the following error:
Traceback (most recent call last):
File “test_addRobot.py”, line 27, in
my_world.reset()
File “/home/qingyu/.local/share/ov/pkg/isaac_sim-2022.2.0/exts/omni.isaac.core/omni/isaac/core/world/world.py”, line 282, in reset
self._scene._finalize(self.physics_sim_view)
File “/home/qingyu/.local/share/ov/pkg/isaac_sim-2022.2.0/exts/omni.isaac.core/omni/isaac/core/scenes/scene.py”, line 292, in _finalize
robot.initialize(physics_sim_view)
File “/home/qingyu/.local/share/ov/pkg/isaac_sim-2022.2.0/exts/omni.isaac.core/omni/isaac/core/articulations/articulation.py”, line 163, in initialize
self._articulation_view.initialize(physics_sim_view=physics_sim_view)
File “/home/qingyu/.local/share/ov/pkg/isaac_sim-2022.2.0/exts/omni.isaac.core/omni/isaac/core/articulations/articulation_view.py”, line 201, in initialize
assert self._physics_view.is_homogeneous
File “/home/qingyu/.local/share/ov/pkg/isaac_sim-2022.2.0/kit/extsPhysics/omni.physics.tensors-104.1.6-5.1/omni/physics/tensors/impl/api.py”, line 156, in is_homogeneous
return self._backend.is_homogeneous
AttributeError: ‘NoneType’ object has no attribute ‘is_homogeneous’
Any ideas how to solve it? When I comment out the line
articulated_system_1 = my_world.scene.add(Robot(prim_path=“/World/myrobot”, name=“robot1”))
The error goes away, but I cannot see the robot in the scene.