MDDS30 ROS 2 Controller

A ROS 2 package for controlling the Cytron MDDS30 Dual Channel 30A Motor Driver via serial communication.
This is a port of the original ROS 1 package by r1b4z01d to ROS 2.

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Features

• Control left and right motors independently via ROS 2 topics.
• Integrate with joystick or gamepad using joy and teleop_twist_joy.
• Launch-ready configuration for quick setup.
• Tested on ROS 2 Kilted Kaiju (adapt to your distribution as needed).

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ROS 2 Node / Topic Flow

flowchart TD
    A[Joystick/Gamepad] -->|/joy| B[joy_node]
    B -->|sensor_msgs/Joy| C[teleop_twist_joy]
    C -->|geometry_msgs/Twist| D[mdds30_controller]
    D -->|std_msgs/Int16| E[Motor Driver MDDS30]

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• /joy → Raw joystick data.
• /cmd_vel → Velocity commands from teleop_twist_joy.
• /mdds30_controller/motor_left & /mdds30_controller/motor_right → Direct motor speed control topics.

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Installation

Clone the Repository

cd ~/ros2_ws/src
git clone https://github.com/iot-forge/mdds30_ros2_controller.git

Install Dependencies

sudo apt install ros-kilted-joy ros-kilted-teleop-twist-joy joystick

Add User to dialout Group

sudo usermod -a -G dialout $USER
# Log out and back in for changes to take effect

Build

From your workspace root:

colcon build --symlink-install
source install/setup.bash

Usage

Source the Setup File

source ~/ros2_ws/src/mdds30_ros2_controller/install/setup.bash

Launch the Controller

ros2 launch mdds30_ros2_controller mdds30_controller.launch.py

Direct Motor Control

ros2 topic pub -1 /mdds30_controller/motor_right std_msgs/msg/Int16 '{data: 50}'
ros2 topic pub -1 /mdds30_controller/motor_left  std_msgs/msg/Int16 '{data: 50}'

Speed range: -100 (full reverse) to 100 (full forward).

Joystick / Gamepad Control

Start Joystick Node

ros2 run joy joy_node

Verify Joystick Messages

ros2 topic echo /joy

Teleoperation with Twist Messages

ros2 run teleop_twist_joy teleop_node --ros-args --params-file ~/ros2_ws/src/mdds30_ros2_controller/config/teleop.yaml

Ubuntu 24.04 (Noble Numbat) UART Configuration on Raspberry Pi

If you are running this package on a Raspberry Pi using Ubuntu 24.04, you may need to enable and configure UART.

1. Understand the UART Options • PL011 full UART → Better performance, no baud rate drift • miniUART → Baud rate tied to CPU clock, may drift

On Raspberry Pi 4/5, by default: • /dev/ttyAMA0 → PL011 • /dev/ttyS0 → miniUART

2. Check Current UART Devices

ls -l /dev/serial*
ls -l /dev/ttyAMA0 /dev/ttyS0
dmesg | grep tty

3. Edit Boot Configuration

sudo nano /boot/firmware/config.txt

Add:

enable_uart=1
dtoverlay=disable-bt

4. Disable Serial Console (Optional)

sudo systemctl disable serial-getty@ttyAMA0.service
sudo systemctl stop serial-getty@ttyAMA0.service

Edit /boot/firmware/cmdline.txt and remove:

console=serial0,115200
console=ttyAMA0,115200

5. Reboot

sudo reboot

6. Test UART

sudo apt install minicom
minicom -b 115200 -o -D /dev/ttyAMA0

Connect TX → RX for loopback and check echo.

7. Notes for Raspberry Pi 5 • dtoverlay=disable-bt still works. • For GPIO14/15, no extra overlay needed besides enable_uart=1. • For other pins, use overlays like:

dtoverlay=uart2

This gives /dev/ttyAMA1, /dev/ttyAMA2, etc.

License

This project inherits the license of the original ROS 1 package. See LICENSE for details.

Acknowledgements

• Original ROS 1 implementation by r1b4z01d
• Cytron Technologies for the MDDS30 motor driver hardware.