Differential Drive Mobile Robot with Intel RealSense D455

A complete ROS2 Humble workspace featuring a 6-wheel differential drive mobile robot equipped with an Intel RealSense D455 camera for simulation and real-world deployment.

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Features

Differential Drive Robot

• 6-wheel skid-steering configuration for enhanced traction
• Robust differential drive controller with odometry feedback
• Customizable robot dimensions via URDF/xacro files
• Realistic physics simulation in Gazebo

Intel RealSense D455 Camera Integration

• RGB Camera: 1280×720 @ 30Hz
• Depth Camera: 1280×720 @ 30Hz
• 3D Point Cloud: Real-time generation for perception tasks
• Hardware-accurate specifications: FOV, range, physical dimensions

Simulation & Visualization

• Gazebo Classic: Full physics-based simulation
• RViz2: Real-time 3D visualization
• TF Tree: Complete transform hierarchy
• Sensor Plugins: Camera, depth, point cloud generation

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Prerequisites

System Requirements

• OS: Ubuntu 22.04 LTS (Jammy)
• ROS2: Humble Hawksbill
• Gazebo: Gazebo Classic 11
• Python: 3.10+

Required ROS2 Packages

sudo apt update
sudo apt install -y \
  ros-humble-desktop \
  ros-humble-gazebo-ros-pkgs \
  ros-humble-xacro \
  ros-humble-robot-state-publisher \
  ros-humble-joint-state-publisher \
  ros-humble-rviz2 \
  ros-humble-tf2-tools \
  ros-humble-realsense2-camera \
  python3-colcon-common-extensions

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Installation

1. Clone the Repository

Create a new workspace folder and clone the repository into it:

cd ~
mkdir -p ws_ddmobile
cd ws_ddmobile
git clone https://github.com/1sznkaveesh/D455-Camera-Integration-ROS2.git .

2. Install Dependencies

cd ~/ws_ddmobile
rosdep install --from-paths src --ignore-src -r -y

3. Build the Workspace

colcon build --symlink-install

4. Source the Workspace

source install/setup.bash

Tip: Add this to your ~/.bashrc for automatic sourcing:

echo "source ~/ws_ddmobile/install/setup.bash" >> ~/.bashrc

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Quick Start

Launch the Robot in Gazebo

source ~/ws_ddmobile/install/setup.bash
ros2 launch mobile_dd_robot gazebo_model.launch.py

This will:

• Start Gazebo with an empty world
• Spawn the robot with the D455 camera
• Initialize all sensors and controllers
• Publish transforms and robot state

Visualize in RViz2

Open a new terminal:

source ~/ws_ddmobile/install/setup.bash
rviz2

Quick RViz2 Setup:

1. Fixed Frame: Set to odom
2. Add: RobotModel
3. Add: Image → Topic: /camera/d455/image_raw
4. Add: PointCloud2 → Topic: /camera/d455/points
   • Size (m): 0.1
   • Style: Flat Squares
   • Color Transformer: RGB8

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Usage

Control the Robot

Using Teleop Twist Keyboard (Optional)

sudo apt install ros-humble-teleop-twist-keyboard
ros2 run teleop_twist_keyboard teleop_twist_keyboard

View Camera Feeds

RGB Image

ros2 run rqt_image_view rqt_image_view /camera/d455/image_raw

Depth Image

ros2 run rqt_image_view rqt_image_view /camera/d455/depth/image_raw

Monitor Topics

# List all active topics
ros2 topic list

# Echo odometry data
ros2 topic echo /odom

# Check camera info
ros2 topic echo /camera/d455/camera_info

Visualize TF Tree

# View TF tree
ros2 run tf2_tools view_frames

# Open the generated PDF
evince frames.pdf

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Workspace Structure

ws_ddmobile/
├── build/              # Build artifacts (auto-generated)
├── install/            # Installation directory (auto-generated)
├── log/                # Build and runtime logs (auto-generated)
├── src/
│   └── mobile_dd_robot/
│       ├── CMakeLists.txt
│       ├── package.xml
│       ├── README.md
│       ├── launch/
│       │   └── gazebo_model.launch.py
│       └── model/
│           ├── camera.xacro         # D455 camera URDF
│           ├── robot.gazebo         # Gazebo plugins
│           └── robot_with_camera.xacro  # Complete robot URDF
└── README.md           # This file

Topics & Services

Subscribed Topics

Topic	Type	Description
/cmd_vel	geometry_msgs/msg/Twist	Velocity commands for robot control

Published Topics

Topic	Type	Description
/odom	nav_msgs/msg/Odometry	Robot odometry (position, velocity)
/camera/d455/image_raw	sensor_msgs/msg/Image	RGB camera feed
/camera/d455/camera_info	sensor_msgs/msg/CameraInfo	RGB camera calibration
/camera/d455/depth/image_raw	sensor_msgs/msg/Image	Depth image
/camera/d455/depth/camera_info	sensor_msgs/msg/CameraInfo	Depth camera calibration
/camera/d455/points	sensor_msgs/msg/PointCloud2	3D point cloud
/tf	tf2_msgs/msg/TFMessage	Transform tree
/tf_static	tf2_msgs/msg/TFMessage	Static transforms

Transform (TF) Tree

odom
 └── body_link
      ├── left_wheel_1_link
      ├── left_wheel_2_link
      ├── left_wheel_3_link
      ├── right_wheel_1_link
      ├── right_wheel_2_link
      ├── right_wheel_3_link
      └── camera_link
           ├── camera_depth_frame
           └── camera_optical_frame

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