ROS 2

Connect Marty V2 to ROS 2 over USB, Wi-Fi or an onboard Pi expansion UART. The standalone driver provides accelerometer, joint and battery topics, connection services and a movement action. Commands run from a Bash terminal on Linux.

Start here

  1. Install and connect — build on Linux, configure the machine and robot, then read acceleration.
  2. Topics, services and movement — inspect the ROS graph and send movement commands.
  3. RViz simulation — run a simulated Marty and control its joints without hardware.
  4. Onboard Pi, camera and RViz — run the driver on the Pi, receive encoded video on another Linux machine and view ROS images.

Source: robotical/marty-ros2. Workstation target: Ubuntu 24.04, ROS 2 Jazzy and Python 3.12. The onboard example uses 64-bit Raspberry Pi OS with a Jazzy container on the Pi.

ROS graph

Marty ROS 2 node, topics, services and action

/marty/marty_driver owns one MartyPy connection. ROS subscribers receive measurement topics; service and action clients send requests to the driver. The firmware generates the movements.

Each robot uses a separate namespace. There is no dependency on Axiom or a dashboard.

Connection and telemetry

The guide starts the driver disconnected. /marty/connect opens the configured connection and MartyPy starts telemetry at subscribe_rate_hz. There is no separate acquisition service. A ros2 topic echo command subscribes to an existing ROS topic; stopping that echo does not stop the driver or firmware telemetry.

/marty/disconnect closes the connection and disables automatic reconnect. Driver measurement topics use best-effort QoS. The optional workstation camera receiver publishes Image messages with reliable, volatile, depth-1 QoS. /marty/status is reliable and transient-local.

Onboard Pi and workstation

The onboard example runs Jazzy's headless Marty driver in a Docker container on a 64-bit Raspberry Pi OS host. The native Pi camera streams H.264/MPEG-TS over TCP; a workstation receiver publishes /marty/camera/image_raw for an RViz Image display. ROS DDS carries Marty telemetry/control separately. Startup remains manual, and no calibrated camera TF/CameraInfo is supplied.

Axiom can use its separate host driver on that workstation. Axiom ROS 2 describes its sensors and outputs; sharing a ROS domain lets applications consume both without merging their firmware or connections.

Current scope

The IMU topic contains acceleration in m/s², including gravity; gyro and orientation are unavailable. Joint positions are in radians. Movement goals use firmware degrees and millimetres.

The driver exposes walk, dance, kick, stand and single-joint movement. RViz simulation displays a separate simulated Marty. Displaying measured joints from physical Marty still needs a calibrated joint mapping; velocity control and odometry are not included. Validation details distinguish automated checks from physical tests.

Task Runner