API Reference

Complete reference for the ROS2 interfaces of the WMX R2 packages.

Three packages make up WMX R2:

Package	Contents
wmx_r2_message	One message (AxesStatus) and 22 services. Interfaces only — no nodes, and no dependency on the WMX3 SDK.
wmx_r2_package	The ten nodes that talk to the WMX3 SDK, three launch files, and the per-robot example configurations.
wmx_r2_control	The ros2_control hardware interface (wmx_r2_control/WmxSystemHardware), URDF xacros, controller YAMLs, and launch files.

How to read this section

Two facts explain most of the interface layout.

Commands are services; only streamed data is a topic. Servo power, axis configuration, homing, manual motion, I/O, and EtherCAT diagnostics are all request/response. The topics carry feedback out and trajectory or velocity streams in, nothing else. Multi-waypoint trajectories are the one action.

Most nodes are lifecycle nodes, and their interfaces exist only while they are active. wmx_lifecycle_manager_node brings them up when the engine starts communicating and takes them down when it stops. If ros2 topic list or ros2 service list looks empty, check the node states before anything else:

wros ros2 service call /wmx/lifecycle/get_node_states wmx_r2_message/srv/GetNodeStates "{}"

Note

There is a second, non-ROS 2 way into the same engine.

The WMX Runtime ships a browser UI — WOS, NetConfigurator, and MotionScope — that sets and tests axis parameters, servo power, homing, jogging, and I/O directly. It is the fastest way to tell an engine problem from a WMX R2 problem, and it is where the ENI file is generated. See WMX Web Tools (WOS, NetConfigurator, MotionScope).

Below the ROS 2 layer is the vendor SDK these nodes are built on. Its reference ships with the runtime at /opt/wmx3/Doc/Web/ — see The WMX3 API Underneath WMX R2.

Interfaces by node

Node	Lifecycle	Interfaces
wmx_engine_node	no	/wmx/engine/set_engine, set_communication, get_engine_status, import_and_set_all, get_axis_param
wmx_lifecycle_manager_node	no	/wmx/lifecycle/set_node_state, get_node_states
wmx_core_motion_node	yes	/wmx/axes/* services; publishes /wmx/axes/status
wmx_io_node	yes	/wmx/io/* — input and output, by bit and by byte
wmx_ethercat_node	yes	/wmx/ecat/* — master info, register read, scan, hot-connect
joint_state_broadcaster	yes	Publishes /joint_states and the simulator mirrors
joint_trajectory_controller	yes	FollowJointTrajectory action server
joint_position_controller	yes	Subscribes to the MoveIt Servo trajectory stream
gripper_controller	yes	/wmx/set_gripper
differential_drive_controller	yes	/cmd_vel_safe in; /odom_enc, /omega_enc, /omega_cmd out

• Communication Overview
• ROS2 Services
  • Service summary
  • Engine services
  • Lifecycle services
  • Axis services
  • I/O services
  • EtherCAT services
  • Gripper service
  • Startup sequence
  • Error handling
  • See also
• ROS2 Topics
  • Topic summary
  • Where the data flows
  • Manipulator feedback
  • Controller arbitration topics
  • Streamed trajectory input
  • Differential drive topics
  • Checking topics at runtime
  • See also
• ROS2 Actions
  • FollowJointTrajectory
• wmx_r2_message
  • Overview
  • Conventions
  • Dependencies
  • Message definitions
  • Service definitions
  • Building the package
  • See also
• wmx_r2_package
  • Overview
  • Package structure
  • Dependencies
  • Node coordination
  • General nodes
  • Manipulator controllers
  • Differential drive controller
  • Launch files
  • Configuration files
  • Building the package
  • See also
• wmx_r2_control
  • Overview
  • Package structure
  • WmxSystemHardware
  • Launch files
  • Controller configuration
  • See also
• The WMX3 API Underneath WMX R2
  • Where the reference lives
  • What is in the API manual
  • How WMX R2 maps onto it