  <link name="world">
    <inertial>
      <mass value="0"/>
      <inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
    </inertial>
  </link>
  <joint name="fixed_joint" type="fixed">
    <parent link="world"/>
    <child link="baseLink"/>
  </joint>
</robot>
