GAZEBO中插入这段运动控制插件的代码打开gazebo中小车翻倒了这是为什么？

<gazebo>
  <plugin name="skid_steer_drive_controller" filename="libgazebo_ros_skid_steer_drive.so">

    <alwaysOn>true</alwaysOn>

    <updateRate>5</updateRate>

   <leftFrontJoint>wheel1_joint</leftFrontJoint>

    <rightFrontJoint>wheel3_joint</rightFrontJoint>

   <leftRearJoint>wheel2_joint</leftRearJoint>

    <rightRearJoint>wheel4_joint</rightRearJoint> 


    <wheelSeparation>0.060</wheelSeparation> 

    <wheelDiameter>0.040</wheelDiameter>

    <torque>20</torque>

    <commandTopic>cmd_vel</commandTopic>

    <odometryTopic>odom</odometryTopic>

    <odometryFrame>odom</odometryFrame>

    <robotBaseFrame>base_link</robotBaseFrame>

    <broadcastTF>1</broadcastTF>

  </plugin>
</gazebo>

https://bbs.csdn.net/topics/396026622