mujoco

<!-- This file is a playground for understanding different rotations.
     Currently, two examples are given:
     - A rotation in the xy plane about a ball joint located in the corner of a box.
     - A rotation in the xy plane about a free joing located in the center of a box.
-->

<mujoco>
  <option density="1000">
    <flag gravity="disable"/>
  </option>

  <worldbody>
    <geom type="plane" size="10 10 .1" rgba="1 1 1 1"/>
    <light pos="0 0 20"/>
    <body name="body_ball" pos="0 0 .5">
      <geom type="box" size=".5 .5 .1" pos="0 0 0"/>
      <joint name="ball" pos=".5 .5 0" axis="0 0 1" type="ball"/>
    </body>
    <body name="body_free" pos="3 0 .5">
      <freejoint name="free"/>
      <geom type="box" size=".5 .5 .1" pos="0 0 0"/>
    </body>
  </worldbody>

  <actuator>
    <general name="ball" joint="ball" dyntype="integrator" gear="0 0 1" ctrllimited="true" ctrlrange="-100 100"/>
    <general name="free" joint="free" dyntype="integrator" gear="0 0 0 0 0 1" ctrllimited="true" ctrlrange="-100 100"/>
  </actuator>
</mujoco>