Create Wall Following Package

To set up your wall following package within the driver stack container follow these steps:

1️⃣ Create the Wall Follow Package

Inside the driver stack container, navigate to your ROS 2 workspace ~/f1tenth_ws/src and create a new package:

cd ~/f1tenth_ws/src
ros2 pkg create wall_follow_package --build-type ament_python --dependencies rclpy sensor_msgs std_msgs

Note

Dependencies

• rclpy (ROS Client Library for Python)

• sensor_msgs (Standard Messages for Sensors)

2️⃣ Modify package.xml

Ensure package.xml includes dependencies like rclpy, sensor_msgs, and std_msgs. Open package.xml and add:

<depend>rclpy</depend>
<depend>sensor_msgs</depend>
<depend>std_msgs</depend>

If you’re using C++ instead of Python, also ensure you have:

<depend>rclcpp</depend>
<depend>tf2_ros</depend>
<depend>geometry_msgs</depend>

3️⃣ Modify CMakeLists.txt (If Using C++)

If you’re using C++, modify CMakeLists.txt to include:

find_package(rclcpp REQUIRED)
find_package(sensor_msgs REQUIRED)
find_package(std_msgs REQUIRED)

Ensure the add_executable or ament_target_dependencies includes the necessary dependencies.

4️⃣ Install Dependencies Using rosdep

Run the following to install missing dependencies:

cd ~/f1tenth_ws
rosdep install --from-paths src --ignore-src -r -y

5️⃣ Implement the Wall Follow Node

You’ll create a wall follow node that listens to LiDAR data (/scan) and publishes steering commands to stay near a wall.

Example: Python Wall Follow Node (wall_follow_node.py)

Create a file inside wall_follow_package/wall_follow_node.py:

6️⃣ Make It Executable

Modify setup.py inside wall_follow_package:

entry_points={
    'console_scripts': [
        'wall_follow_node = wall_follow_package.wall_follow_node:main',
    ],
},

7️⃣ C++ Alternative (Optional)

Run the following:

cd ~/f1tenth_ws
colcon build --packages-select wall_follow_package
source install/setup.bash
ros2 run wall_follow_package wall_follow_node

Alternative: C++ Wall Follow Node Implementation

Students who prefer C++ can use this starter code instead. Create a file wall_follow_node.cpp: