Configuration file¶

The configuration file is the main user file to set different controllers and parameters. The configuration file is a YML file located in config/.

declare your different dynamixel controllers

name of your controller
type : joint state, position, velocity, trajectory

joint : set joint name (same as in urdf)

dynamixel_controllers:

  joint_state_controller:
    type: joint_state_controller/JointStateController
    publish_rate: 10

  traj_controller:
    type: position_controllers/JointTrajectoryController
    joints:
      - JOINT_NAME1

  vel_controller:
    type: velocity_controllers/JointVelocityController
    joint: JOINT_NAME2

declare your dynamixel control parameters

serial interface: path to the USB to serial interface for example /dev/ttyUSB0

loop_frequency: frequency at which the control loop will run (in Hz)

cycle_time_error_threshold: how much delay is tolerated on the control loop (in s)

baudrate: baud-rate for the serial communication with actuators (in bauds)

read_timeout: timeout on the reception of replies from the servos (in s)

read_timeout: (for the scan only) timeout on the reception of replies from the servos (in s)

servos: object which keys are the name of the joints and which values contain:

id (required): actuator’s ID to its name (the one used in the controller list and in URDF)

offset: correction to be applied to the angle of the joint (in rad)

command_interface: the command mode (velocity or position)

max_speed: maximal allowed velocity (rad/s), for now, works only for joints in position control

reverse: clockwise and anticlockwise

default_command_interface: if no command_interface is defined for a joint, this value is used instead

Below one example of configuration file, see sample example

dynamixel_controllers:

  joint_state_controller:
    type: joint_state_controller/JointStateController
    publish_rate: 10

  traj_controller:
    type: position_controllers/JointTrajectoryController
    joints:
      - arm_joint_2

  vel_controller:
    type: velocity_controllers/JointVelocityController
    joint: arm_joint_1

dynamixel_control:
  serial_interface: /dev/ttyUSB0
  loop_frequency: 500
  cycle_time_error_threshold: 0.002
  baudrate: 3000000 # in bauds
  read_timeout: 0.005 # in seconds
  scan_timeout: 0.005 # in seconds
  # Cofniguration of the servos
  servos:
    arm_joint_1:
      # hardware ID of the actuator
      id: 2
      offset: 3.14159265359
      # offset to be added, in radians, to the position of an actuator
      #max-speed: 4.0 # in rad
      command_interface: velocity
    arm_joint_2:
      id: 1
      # max joint speed
      # it shoud NOT be used for actuators in velocity mode
      offset: 3.1 # in rad/s
      # this actuator is set in reverse mode for the speed and position
      #reverse: false
  # default mode
  default_command_interface: position