Lula robot description editor

2024-02-01 07:17:47 [72,727ms] [Error] [omni.ui.python] IndexError: list index out of range

  /home/user/.local/share/ov/pkg/isaac_sim-2023.1.1/exts/omni.isaac.robot_description_editor/omni/isaac/robot_description_editor/ _on_select_sphere_gen_link
  /home/user/.local/share/ov/pkg/isaac_sim-2023.1.1/exts/omni.isaac.robot_description_editor/omni/isaac/robot_description_editor/ _refresh_sphere_gen_link_combobox
  /home/user/.local/share/ov/pkg/isaac_sim-2023.1.1/exts/omni.isaac.robot_description_editor/omni/isaac/robot_description_editor/ _on_selection
  /home/user/.local/share/ov/pkg/isaac_sim-2023.1.1/exts/omni.isaac.robot_description_editor/omni/isaac/robot_description_editor/ _on_combobox_selection
  /home/user/.local/share/ov/pkg/isaac_sim-2023.1.1/exts/omni.isaac.ui/omni/isaac/ui/ <lambda>

And why is the selected articulation /World/ur5e_shadow/base_link? I can’t select the link.

This is my USD files. (6.9 MB)

I want to know how to solve this problem.

@1878720579 i am just another user, but upon checking out your robot, i am wondering if it’s because of the way your file is set up. take a look at two relevant threads where dan.sandberg had similar experiences and a corresponding process around it

Thanks @Simplychenable . I’ve tried these methods but it doesn’t seem to fix the issue. I don’t know what causes these problems, and I hope to give me a reasonable solution. This problem has been bothering me for a long time and has caused me to be unable to continue. Hope there is a relevant developer to help me.

The robot description editor has not been tested on assembled assets, and so I believe you are noticing a bug/shortcoming with the robot description editor. However, there is a reason that we didn’t test using the robot description editor on assembled assets, which is that it is (as far as I know) not going to be the right workflow to pursue for any use-case.

Lula motion generation algorithms require a URDF file that fully describes the robot being controlled, and a matching Lula robot description file. This means that if you use the asset above to generate a robot description file, that file is not going to work unless you have a URDF file that also describes the composed robot. And if you had such a URDF file, you could import that URDF file directly with the URDF importer (which would avoid the possibility of subtle bugs where the URDF and the USD Articulation don’t match).

Additionally, Lula motion generation algorithms such as RMPflow are intended for use on the arm part of the robot, and not on the manipulator. This means that you can tell Lula that it is simply controlling a UR5e, and it doesn’t need to know much about the rest of the robot. There are two considerations I would make

1: If you want to extend collision avoidance to the Shadow-Hand, then you can add collision spheres that are part of the flange link of the UR5e that encompass the shadow hand. If you want the shadow hand to be present in the picture above as a visual aid for doing this, I expect that if you re-assembled the robot with the single_robot flag set to false, it would resolve your error above (the robot description editor would then be working with just the UR5e part of the asset). Note that if you fully cover the shadow hand in spheres, no Lula motion generation algorithm is going to be willing to let the fingers get close to any obstacles to manipulate them.

2: If you want to control where the base of the wrist of the Shadow-Hand is rather than where the flange link is, see this tutorial for adding new end effector frames to a robot URDF file.

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