Hi all,

Since URDF does not support closed loop links I closed the loop using a hidden joint:hinge in the .gazebo.xacro file for my robot, following some ROS answers for a similar question.

<gazebo>
  <joint:hinge name="${prefix}_${suffix}_parallel_hinge2">
      <body1>${link}</body1>
      <body2>${prefix}_${suffix}_wheel_HubTop</body2>
      <anchor>${prefix}_${suffix}_wheel_HubTop</anchor>
      <axis>0 1 0</axis>
      <anchorOffset>0 0 -0.045</anchorOffset>
  </joint:hinge>
</gazebo>

However, when I change the joint:hinge to joint:slider the model no longer has this joint in the gazebo (show joints).

<gazebo>
  <joint:slider name="${prefix}_${suffix}_parallel_hinge2">
      <body1>${link}</body1>
      <body2>${prefix}_${suffix}_wheel_HubTop</body2>
      <anchor>${prefix}_${suffix}_wheel_HubTop</anchor>
      <axis>0 1 0</axis>
      <anchorOffset>0 0 -0.045</anchorOffset>
  </joint:slider>
</gazebo>

Why is that? Any workaround? Also, joint:screw didn't work either.

Thank you

Cheers!

CS