open_manipulator_x

In this repo, you can find the integration of OpenManipulatorX with ros2_control. Based on the code provided by Robotis, updated to work with the Humble distribution of ROS 2. You can use it by including open_manipulator_x_macro in the URDF of your robot, for example:

<xacro:include
    filename="$(find open_manipulator_x_description)/urdf/open_manipulator_x_macro.urdf.xacro"
    ns="manipulator" />
  <xacro:manipulator.open_manipulator_x parent_link="cover_link"
    xyz="-0.1 0.0 0.0"
    rpy="0.0 0.0 0.0"
    use_sim="False"
    collision_enabled="True"
    usb_port="/dev/ttyUSB0"
    baud_rate="1000000"
    joint1_limit_min="-2.356"
    joint1_limit_max="5.934" />

Parameters description:

• parent_link link to which manipulator will be attached (with transform specified by xyz and rpy parameters)
• use_sim - whether simulation ros2_control plugin should be included instead of real hardware one (currently only Gazebo is supported).
• collision_enabled - due to lack of dedicated collision meshes of open_manipulator_x, visual ones are also used for collisions. This can result in a drop in simulation performance, you can opt to disable collisions in this case.
• usb_port in case of using hardware, name of USB port where manipulator is connected (e.g. /dev/ttyUSB0).
• baud_rate in case of using hardware, a baud rate of communication with servos.

Additionally, you have to add an appropriate controller, an example is provided in the open_manipulator_x_hardware/config directory.

Usage

Before activating torque, the current position of the manipulator is read, then it is set as a goal position - the manipulator stays in the position that it was activated.

Turning off torque

One useful thing that can be a little tricky is turning off the torque of the manipulator's joints. To do it, you have to manually set the hardware controller to an inactive state:

ros2 service call /controller_manager/set_hardware_component_state \
  controller_manager_msgs/srv/SetHardwareComponentState \
  "{name: 'manipulator', target_state: {id: 0, label: 'inactive'}}"

To activate it again use the same service, but change the label to active.