ROS Controllers Configuration

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Overview

This package provides the necessary ROS controllers needed to get MoveIt to control any physical arm on an X-Series Locobot. It essentially takes in Joint Trajectory commands from MoveIt (via the FollowJointTrajectoryAction interface) and then publishes joint commands at the right time to the xs_sdk node. Currently, only the ‘position’ values in the Joint Trajectory messages are used since that provides the smoothest motion. Note that while this package is really only meant to be used with MoveIt, it could technically be used with any other node that can interface properly with the joint_trajectory_controller package.

Structure

../_images/xslocobot_ros_control_flowchart.png

This package builds on top of the interbotix_xslocobot_control package (which starts the xs_sdk node), and is typically used in conjunction with the interbotix_xslocobot_moveit package. To get familiar with the nodes in those packages, feel free to look at their READMEs. The other nodes are described below:

  • controller_manager - responsible for loading and starting a set of controllers at once, as well as automatically stopping and unloading those same controllers
  • xs_hardware_interface - receives joint commands from the ROS controllers and publishes them to the correct topics (subscribed to by the xs_sdk node) at the appropriate times

Usage

This package is not meant to be used by itself but included in a launch file within your custom ROS package (which should expose a FollowJointTrajectoryAction interface). To run this package, type the line below in a terminal (assuming a Locobot with a PincherX-100 is being launched).

$ roslaunch interbotix_xslocobot_ros_control xslocobot_ros_control.launch robot_model:=px100

This is the bare minimum needed to get up and running. Take a look at the table below to see how to further customize with other launch file arguments.

Argument Description Default Value
robot_model model type of the Interbotix Locobot such as ‘locobot_base’ or ‘locobot_wx250s’ “”
robot_name name of the robot (could be anything but defaults to ‘locobot’) locobot
show_lidar set to true if the lidar is installed on the robot; this will load the lidar related links to the ‘robot_description’ parameter $(arg use_lidar)
external_urdf_loc the file path to the custom urdf.xacro file that you would like to include in the Interbotix robot’s urdf.xacro file  
use_rviz launches RViz false
use_camera if true, the RealSense D435 camera nodes are launched false
mode_configs the file path to the ‘mode config’ YAML file refer to xslocobot_ros_control.launch
dof the degrees of freedom of the arm 5