Repo Description

ROS 2 Humble development workspace running inside a Docker container, intended for robotics development with custom interfaces and messages. This repository includes ROS 2 packages, custom message definitions, and a Docker-based development environment.

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Repository structure

mec_ws/
├── src/
│   ├── Actuator-dynamics-identification/   # Submodule (external repository)
│   └── pi3hat_moteus_int_msgs/              # Custom ROS 2 message package
├── Dockerfile
├── docker-compose.yml
├── entrypoint.sh
└── README.md

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Submodules

Git submodule:

• Actuator-dynamics-identification 👉 https://github.com/CentroEPiaggio/Actuator-dynamics-identification

After cloning this repository, make sure to initialize and update submodules:

git submodule update --init --recursive

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pi3hat_moteus_int_msgs package

The package pi3hat_moteus_int_msgs defines custom ROS 2 message types used for interfacing a Raspberry Pi + pi3hat with moteus motor controllers.

Location

src/pi3hat_moteus_int_msgs

Message definitions

msg/
├── FeetPos.msg
├── JointsCommand.msg
├── JointsStates.msg
├── OmniMulinexCommand.msg
├── PacketPass.msg
└── QuadFootState.msg

These messages are meant to:

• Represent joint commands and joint states
• Exchange structured data between low-level motor control and higher-level ROS 2 nodes
• Provide a clean ROS 2 interface for pi3hat + moteus-based systems

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Requirements

• Docker
• Docker Compose
• Linux with X11 (for GUI tools such as rqt and PlotJuggler)

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Docker-based development environment

The Docker image is based on ROS 2 Humble Desktop and includes:

• colcon, rosdep, vcstool
• ros2_control and controllers
• URDF / xacro tools
• GUI tools: rqt, PlotJuggler (+ ROS plugin)
• Non-root user: ros
• Workspace: /home/ros/colcon_ws

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Getting started

1. Clone the repository

git clone https://github.com/lo-imperatore/mec_ws.git
cd mec_ws
git submodule update --init --recursive

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2. Allow Docker to access X11 (GUI)

On the host machine:

xhost +local:docker

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3. Build and start the container

From the repository root:

docker compose up --build

Or run in detached mode:

docker compose up --build -d

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4. Open a shell inside the container

If running detached:

docker compose exec ros2-dev bash

You will be logged in as user ros in:

/home/ros/colcon_ws

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Volumes and mounts

• ./src → /home/ros/colcon_ws/src
• /tmp/.X11-unix → GUI forwarding
• ${HOME}/.ssh → SSH access from inside the container (read-only)
• ros_home → persistent /home/ros

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ROS 2 networking

Default configuration (can be changed in docker-compose.yml):

ROS_DOMAIN_ID=0
RMW_IMPLEMENTATION=rmw_fastrtps_cpp
ROS_LOCALHOST_ONLY=0

Ensure all ROS 2 machines use the same ROS_DOMAIN_ID.

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Stopping the environment

docker compose down

Remove containers and volumes:

docker compose down -v

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Notes

• Custom messages in pi3hat_moteus_int_msgs must be built with colcon before use.
• SSH access is required to connect from inside the Docker container to a Raspberry Pi running the low-level control stack.

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License

Add license information here.