mujoco

<mujoco>
  <option integrator="implicitfast" viscosity="10"
          sleep_tolerance="0.01">
    <flag sleep="enable" gravity="disable"/>
  </option>

  <worldbody>
    <body name="flex_body">
      <flexcomp name="f1" type="grid" dim="1" count="3 1 1"
                spacing=".05 .05 .05" radius=".01" mass="1">
        <edge equality="false" stiffness="100" damping="10"/>
      </flexcomp>
    </body>
  </worldbody>
</mujoco>