moveit_ros_control_interface

ros_control controller manager interface for MoveIt

Links
- Rosindex

README

MoveIt ROS Control Plugin

This package provides plugins of base class moveit_controller_manager::MoveItControllerManager and a new plugin base class for moveit_controller_manager::MoveItControllerHandle allocators. The allocator class is necessary because moveit_controller_manager::MoveItControllerHandle needs a name passed to the constructor. Two variants are provided, moveit_ros_control_interface::Ros2ControlManager for interfacing a single ros_control node and moveit_ros_control_interface::Ros2ControlMultiManager for seamless integration with any number of ros_control nodes.

moveit_ros_control_interface::Ros2ControlManager

This plugin interfaces a single ros_control-driven node in the namespace given in the ~ros_control_namespace ROS parameter. It polls all controllers via the list_controllers service and passes their properties to MoveIt. The polling is throttled to 1 Hertz.

Handle plugins

The actual handle creation is delegated to allocator plugins of base class moveit_ros_control_interface::ControllerHandleAllocator. These plugins should be registered with lookup names that match the corresponding controller types.

Currently plugins for position_controllers/JointTrajectoryController, velocity_controllers/JointTrajectoryController and effort_controllers/JointTrajectoryController are available, which simply wrap moveit_simple_controller_manager::FollowJointTrajectoryControllerHandle instances.

Setup

In your MoveIt launch file (e.g. ROBOT_moveit_config/launch/ROBOT_moveit_controller_manager.launch.xml), set the moveit_controller_manager parameter:

<param name="moveit_controller_manager" value="moveit_ros_control_interface::Ros2ControlManager" />

Make sure to set the ros_control_namespace parameter to the namespace (without the /controller_manager/ part) of the ros_control-based node you like to interface. If you are using moveit_setup_assistant, you can add it to ROBOT_moveit_config/config/moveit_controllers.yaml, e.g.:

ros_control_namespace: /ROS_CONTROL_NODE
controller_list:
  - name: /ROS_CONTROL_NODE/position_trajectory_controller
    action_ns: follow_joint_trajectory
    type: FollowJointTrajectory
    default: true
    joints:
      - joint_a1
      - joint_a2
      - joint_a3
      - joint_a4
      - joint_a5
      - joint_a6
      - joint_a7

Controller switching

MoveIt can decide which controllers have to be started and stopped. Since only controller names with registered allocator plugins are handed over to MoveIt, this implementation takes care of stopping other conflicting controllers based on their claimed resources and the resources for the to-be-started controllers.

Namespaces

All controller names get prefixed by the namespace of the ros_control node. For this to work the controller names should not contain slashes. This is a strict requirement if the ros_control namespace is /.

moveit_ros_control_interface::Ros2ControlMultiManager

This plugin does not need further configuration. It polls the ROS main for services and identifies ros_control nodes automatically. It spawns moveit_ros_control_interface::Ros2ControlManager instances with their namespace and takes cares of proper delegation.

Setup

Just set the moveit_controller_manager parameter in your MoveIt launch file (e.g. ROBOT_moveit_config/launch/ROBOT_moveit_controller_manager.launch.xml)

<param name="moveit_controller_manager" value="moveit_ros_control_interface::Ros2ControlMultiManager" />