mujoco

<mujoco>

  <worldbody>
    <geom type="plane" size="1 1 .01"/>
    <light pos="0 0 2"/>
    <body pos="0 -.1 .3">
      <joint name="slide" type="slide" axis="1 0 0"/>
      <geom type="box" size=".05 .05 .05"/>
    </body>
    <body pos="0 .1 .3" mocap="true">
      <geom type="box" size=".05 .05 .05"/>
    </body>
  </worldbody>

  <actuator>
    <motor name="stateless" joint="slide"/>
    <general name="stateful" joint="slide" dyntype="integrator"/>
  </actuator>

  <keyframe>
    <key time=".1"/>
    <key qpos=".2"/>
    <key qvel=".3"/>
    <key act=".4"/>
    <key ctrl=".5 .6"/>
    <key mpos=".1 .2 .3"/>
    <key mquat="1 1 1 1"/>
  </keyframe>
</mujoco>