A differential drive mobile robot simulation package for ROS2 Humble with stable ball caster design for Gazebo Ignition.

• Stable Differential Drive: 2 powered wheels with differential drive controller
• No-Hop Ball Casters: Redesigned from complex swivel casters to simple ball casters, eliminating reverse motion hopping
• Dual Format Support: Both SDF (for Gazebo) and URDF (for RViz/Nav2) formats
• Production Ready: Tested and verified in Gazebo Ignition and RViz
• Extensible Design: Ready for sensor integration (Lidar, Camera, IMU)

ros2 launch donar_robot_description gazebo_sdf.launch.py

ros2 run rviz2 rviz2 -d src/donar_robot_description/rviz/urdf_config.rviz

ros2 run teleop_twist_keyboard teleop_twist_keyboard \
  --ros-args -r /cmd_vel:=/donar_robot/cmd_vel

• OS: Ubuntu 22.04
• ROS2: Humble
• Gazebo: Ignition Garden or Fortress
• Tools: Colcon, Git

# Create workspace
mkdir -p ~/ros2_ws/src
cd ~/ros2_ws/src

# Clone repository
git clone https://github.com/yourusername/donar_robot_description.git

# Install dependencies
cd ~/ros2_ws
rosdep install --from-paths src --ignore-src -r -y

# Build
colcon build --packages-select donar_robot_description

# Source
source install/setup.bash

Launch Gazebo Simulation:

export GZ_SIM_RESOURCE_PATH=$GZ_SIM_RESOURCE_PATH:~/ros2_ws/install/donar_robot_description/share
ros2 launch donar_robot_description gazebo_sdf.launch.py

Control the Robot:

# Install keyboard teleop
sudo apt install ros-humble-teleop-twist-keyboard

# Run teleop
ros2 run teleop_twist_keyboard teleop_twist_keyboard \
  --ros-args -r /cmd_vel:=/donar_robot/cmd_vel

donar_robot_description/
├── config/              # Controller configurations
├── launch/              # Launch files (Gazebo, RViz)
├── meshes/              # CAD-exported STL meshes
├── models/              # SDF models for Gazebo
│   └── donar_robot/
│       ├── model.config
│       └── model.sdf    # Primary robot definition
├── rviz/                # RViz configurations
├── urdf/                # URDF/xacro files
└── worlds/              # Gazebo world files

Main Files:

• models/donar_robot/model.sdf - Primary robot definition for Gazebo
• urdf/donar_robot.xacro - URDF description for RViz/Nav2
• launch/gazebo_sdf.launch.py - Main simulation launcher

Robot Links:

• base_link - Main robot chassis (35 kg)
• left_wheel_1, right_wheel_1 - Driven wheels (2 kg each)
• left_caster_wheel_1, right_caster_wheel_1 - Ball casters (0.4 kg each)

Topics:

• /donar_robot/cmd_vel - Velocity commands (input)
• /donar_robot/odometry - Odometry feedback (output)
• /joint_states - Joint positions/velocities (output)

• Base robot model with differential drive
• Simplified ball caster design
• Gazebo Ignition integration
• RViz visualization support
• Odometry and joint state publishing
• Teleop control interface

• RPLidar A2 sensor integration
• Intel RealSense camera
• IMU sensor (for sensor fusion)

• Nav2 navigation stack integration
• SLAM capability (slam_toolbox)
• Autonomous waypoint navigation
• Gazebo world scenarios
• Hardware deployment guide

• ROS2 Tutorials: docs.ros.org
• Gazebo Documentation: gazebosim.org
• Project Wiki: Coming soon

Published Topics:

/donar_robot/odometry [nav_msgs/Odometry]
/joint_states [sensor_msgs/JointState]
/clock [rosgraph_msgs/Clock]
/tf [tf2_msgs/TFMessage]

Subscribed Topics:

/donar_robot/cmd_vel [geometry_msgs/Twist]

Parameters:

wheel_separation: 0.52
wheel_radius: 0.14
max_linear_velocity: 3
max_angular_velocity: 3.0

Contributions are welcome! Please feel free to submit issues and pull requests.

# Fork the repository
# Clone your fork
git clone https://github.com/yourusername/donar_robot_description.git

# Create feature branch
git checkout -b feature/your-feature

# Make changes and commit
git commit -m "feat: add your feature"

# Push and create PR
git push origin feature/your-feature

This project is licensed under the MIT License - see the LICENSE file for details.

Dieudonne YUFONYUY

• Email: dieudonne.yufonyuy@gmail.com
• LinkedIn: [https://www.linkedin.com/in/dieudonne-yufonyuy

• ROS2 Community - For excellent documentation and support
• Gazebo Team - For powerful simulation tools
• fusion2urdf - For CAD to URDF conversion
• Open source robotics community

• Navigation2 - ROS2 Navigation Stack
• slam_toolbox - SLAM for ROS2
• gazebo_ros_pkgs - Gazebo ROS integration

⭐ If you find this project useful, please consider giving it a star!

Last Updated: December 2025