ROS Programming: Building Powerful Robots

How does Dynamixel send and receive commands for the movements?

Once you have launched the controller_manager.launch file, you will see a list of topics. Remember to use the following command line to see these topics:

    $ rostopic list
  

These topics will show the state of the motors configured, as follows:

    /diagnostics
    /motor_states/pan_tilt_port
    /rosout
    /rosout_agg
  

If you see /motor_states/pan_tilt_port with the rostopic echo command, you will see the state of all the motors, which, in our case, is only the motor with the ID 6; however, we cannot move the motors with these topics, so we need to run the next launch file to do it.

This launch file will create the necessary topics to move the motors, as follows:

    $ roslaunch dynamixel_tutorials ...