Publishing in different topics for each wheel

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How can I (having a 6-wheeled robot and using the DiffDrivePlugin6w from hectorgazebo plugins) make that each wheel subscribes in a different topic: Now I've been able to make that all the wheels move at the same time (they are all "answering" to the cmd_vel topic), but I'd like something like cmd_vel_front_left topic,....

<gazebo>
  <plugin name="DiffDrivePlugin6W" filename="libdiffdrive_plugin_6w.so">
      <rosDebugLevel>Debug</rosDebugLevel>
      <publishWheelTF>false</publishWheelTF>
      <publishWheelJointState>true</publishWheelJointState>
      <alwaysOn>true</alwaysOn>
      <frontLeftJoint>front_left_wheel_joint</frontLeftJoint>
      <frontRightJoint>front_right_wheel_joint </frontRightJoint>
      <midLeftJoint>medium_left_wheel_joint </midLeftJoint>
      <midRightJoint>medium_right_wheel_joint </midRightJoint>
      <rearLeftJoint>back_left_wheel_joint </rearLeftJoint>
      <rearRightJoint>back_right_wheel_joint </rearRightJoint>
      <wheelSeparation>0.569</wheelSeparation>
      <wheelDiameter>0.145</wheelDiameter>
      <wheelTorque>20</wheelTorque>
      <wheelAcceleration>1.8</wheelAcceleration>
      <commandTopic>cmd_vel</commandTopic>
      <odometryTopic>odom</odometryTopic>
      <odometryFrame>odom</odometryFrame>
      <odometrySource>world</odometrySource>
      <robotBaseFrame>base_link</robotBaseFrame>
      <updateRate>10.0</updateRate>
  </plugin>
</gazebo>

Thanks!!