当你想自己发布odom话题控制rviz里的机器人运动时，发现gazebo也发布了odom话题，此时的一种方法就是把gazebo中的odom话题改名

  <gazebo>
    <plugin name="turtlebot3_burger_controller" filename="libgazebo_ros_diff_drive.so">
      <commandTopic>cmd_vel</commandTopic>
      <odometryTopic>odom2</odometryTopic>
      <odometryFrame>odom</odometryFrame>
      <odometrySource>world</odometrySource>
      <publishOdomTF>true</publishOdomTF>
      <robotBaseFrame>base_footprint</robotBaseFrame>
      <publishWheelTF>false</publishWheelTF>
      <publishTf>true</publishTf>
      <publishWheelJointState>true</publishWheelJointState>
      <legacyMode>false</legacyMode>
      <updateRate>30</updateRate>
      <leftJoint>wheel_left_joint</leftJoint>
      <rightJoint>wheel_right_joint</rightJoint>
      <wheelSeparation>0.160</wheelSeparation>
      <wheelDiameter>0.066</wheelDiameter>
      <wheelAcceleration>1</wheelAcceleration>
      <wheelTorque>10</wheelTorque>
      <rosDebugLevel>na</rosDebugLevel>
    </plugin>
  </gazebo>

<odometryTopic>odom2</odometryTopic>
这样就 成了odom2了