How was ur_moveit.urdf.xacro generated?

[pwspania]

The file used in the manipulation tutorial uses a xacro file that doesn’t exist in the real repo. (https://github.com/UniversalRobots/Universal_Robots_ROS2_Description/tree/humble/urdf) How was it generated? It looks like the following was added, but without explanation of why.

  <link name="ground_plane_box">
    <visual>
        <origin xyz="0 0 0" rpy="0 0 0"/>
        <geometry>
            <box size="1.0 1.0 0.5"/> 
        </geometry>
        <material name="Grey">
            <color rgba="0.7 0.7 0.7 1.0"/>
        </material>
    </visual>
    <collision>
        <origin xyz="0 0 0" rpy="0 0 0"/>
        <geometry>
            <box size="1.0 1.0 0.5"/> 
        </geometry>
    </collision>
</link>
<joint name="ground_plane_box" type="fixed">
    <parent link="world" />
    <child link="ground_plane_box" />
    <origin xyz="0 0 -0.25" rpy="0 0 0" />
</joint>

[albertoezquerro]

Hello @pwspania ,

Yes, we don’t use the exact same repository as the official one, but a customized version of it. This is usually the case in the real world, as you need to do some modifications to the original files in order to adapt them to your personal projects (for instance, to add a gripper). In this case, the section you highlight is just adding a box underneath the robot, in order to avoid Moveit generating plans that go below the ground level, which would cause a collision with the ground.