YAHBOOM G1 Tank ROS 2

Table of Contents

• About The Project
  • Built With
• Getting Started
  • Prerequisites
  • Installation and Setup
  • First Use
• How It Works
• Roadmap
• Contributing
• License
• Contact

About The Project

Built With

Getting Started

This guide will help you set up and run the ROS 2 Python node for the YAHBOOM G1 Tank with Raspberry Pi 4.

• LED Control Package
• Tank Control Package

Prerequisites

Hardware:

• YAHBOOM G1 Tank: Ensure it’s fully assembled and tested for basic operations.
• Raspberry Pi 4: Properly interfaced with the G1 Tank.

Software:

• Ubuntu 22 for Raspberry Pi: Installed and set up on your Raspberry Pi 4. Ubuntu installation guide.
• ROS 2 Humble-desktop: Installed and sourced following the official ROS 2 installation guide.
• Colcon: Required for building and testing ROS packages. Install with:

  sudo apt install python3-colcon-common-extensions
  

For more information on installing Colcon, please refer to the official Colcon installation guide.

• RPI-GPIO: Library to control Raspberry Pi GPIO channels. Install using:

  sudo apt install python3-rpi.gpio
  

Installation and Setup

1. Setting Permissions: If you encounter a “RuntimeError: No access to /dev/mem”, adjust permissions for GPIO access on your Raspberry Pi:

   sudo chmod 777 /dev/mem
   sudo chmod 777 /dev/gpiomem
   

After adjusting, reboot your Raspberry Pi.

1. Clone the Repository: Navigate to your home directory, then run:

   mkdir ~/ros2_ws/
   cd ~/ros2_ws
   git clone https://github.com/jhiggason/yahboomg1tank.git .
   

1. Build the ROS 2 Package: Compile the project using colcon:

   colcon build
   

1. Source the Workspace: After building, source the workspace:

   source ~/ros2_ws/install/setup.bash
   

1. Running the Node: To activate and run your ROS 2 node, execute:

   ros2 run tank_control_pkg tank_control
   

First Use:

Upon successfully setting up and running the node, the YAHBOOM G1 Tank should now respond to the twist messages provided by the turtlesim teleop or any other control method you’ve implemented.

Running the Turtlesim Node To activate and run your turtlesim node, execute:

   ros2 run turtlesim turtle_teleop_key --ros-args --remap /turtle1/cmd_vel:=/cmd_vel
   

Use your arrow keys on your keyboard to move the tank around.

For any issues or to contribute, engage with this GitHub repository.

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How It Works:

The TankControl class, found in tank_control.py, is designed to control a tank-like robot using ROS 2 and Raspberry Pi GPIO pins. It subscribes to ROS 2 topics to receive motion commands and controls the robot’s movement accordingly.

1. Initialization: The class initializes upon instantiation, setting up GPIO pins for the left and right motors and configuring PWM (Pulse Width Modulation) for speed control.

2. ROS 2 Subscriptions: It subscribes to the /cmd_vel topic to receive Twist messages, containing linear and angular velocities for the tank’s movement.

3. Motor Speed and Direction Control: The class processes incoming Twist messages to calculate the speeds for the left and right wheels. It applies a correction factor to the linear velocity and amplifies the angular velocity. The speeds are normalized and used to control the motor direction and speed through GPIO pins.

4. Safety Features: An inactivity timer is implemented to stop the motors if no command is received for a short duration (currently 0.1 seconds), ensuring safety.

Important Parameters:

• GPIO Pins Configuration: self.left_motor_pins and self.right_motor_pins define the GPIO pins for the motors.

• Message Processing: The subscription_callback method processes Twist messages, applying a correction factor and amplifying the angular velocity to determine motor speeds.

• Inactivity Timer: The timer_callback method checks for command inactivity, stopping the motors if no command is received within 0.1 seconds.

Customization:

• Motor Pins: Modify self.left_motor_pins and self.right_motor_pins to match your GPIO configuration.

• Subscription Topic: Change the topic name in create_subscription if needed.

• Control Logic: Adjust the subscription_callback method for different tank motion logic.

• Inactivity Duration: Alter the inactivity duration in timer_callback for different safety requirements.

Careful consideration should be given when modifying GPIO configurations to prevent damage to the Raspberry Pi or connected components.

For more examples, please refer to the Documentation

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Gamepad

In this example we are going to use an Xbox Series X/S controller, connected to bluetooth on the raspberry pi, to send twist MSGs to the /cmd_vel topic. This will control our tank.

*Setting Up Xbox Controller on Ubuntu 22 for ROS 2

1. Disable Secure Boot: If you are doing this on a system other than raspberry pi-please disable secure boot.
   • Enter your PC’s BIOS/UEFI firmware settings during boot, typically by pressing Del, F2, F12, or Esc.
   • Navigate to ‘Boot’ or ‘Security’.
   • Find ‘Secure Boot’ and set it to ‘Disabled’.
   • Save and exit.
2. Update Xbox Controller:
   • On Windows:
     • Connect the controller and open the ‘Xbox Accessories’ app.
     • Follow on-screen instructions if an update is available.
   • On Xbox:
     • Connect the controller, navigate to ‘Settings’ > ‘Devices & connections’ > ‘Accessories’.
     • Update if prompted.
3. Install Xbox Driver for Ubuntu:
   • Install Dependencies:

      sudo apt update
      sudo apt install dkms git
      

- Get `xpadneo` from its repository:

      git clone https://github.com/atar-axis/xpadneo.git
      cd xpadneo
      sudo ./install.sh
      

1. Install Joystick Tools:

    sudo apt update
    sudo apt install jstest-gtk joystick
    

1. Pair Xbox Controller via Bluetooth:
   • Start the Bluetooth CLI tool:

      sudo bluetoothctl
      

- Turn on the agent and set it as default:

      agent on
      default-agent
      

- Scan for devices:

      scan on
      

- Turn on your Xbox controller in pairing mode. Note its MAC address.
- Pair, trust, and connect using the MAC address (replace 'XX:XX:XX:XX:XX:XX'):

      pair XX:XX:XX:XX:XX:XX
      trust XX:XX:XX:XX:XX:XX
      connect XX:XX:XX:XX:XX:XX
      

- Finish:

      scan off
      exit
      

1. Install ros-humble-teleop-twist-joy:

    sudo apt update
    sudo apt install ros-humble-teleop-twist-joy
    

1. Adjust xbox joy settings:

    cd /opt/ros/humble/share/teleop_twist_joy/config/
    sudo nano xbox.config.yaml
    

Edit the file and change the values to 0 and 1.

    enable_button: 0  # Button A
    enable_turbo_button: 1  # Button B
   

Then Ctrl+O then CTRL+X

1. Run Teleop Twist joy

    ros2 launch teleop_twist_joy teleop-launch.py joy_config:='xbox'
    

Now you should be able to control your tank with the xbox controller after pressing the “A” button on the controller and moving the left stick.

Roadmap

• Working ROS 2 that talks on the correct raspberry pi pins
• Improve movement commands to allow for better control of tank
• Use xbox controller to move the tank
• Enable “search” LEDs and servo http://www.yahboom.net/study/G1-T-PI
• Change to a YAML style config
• Create proper guide on how to set it up, devolop it, and maintain it
• Enable camera for remote viewing
• Enable ultra-sonic sensor and servo
• Enable basic obstacle avoidance using ultra-sonic sensor
• Enable advanced obstacle avoidance/path planning via Lidar and Depth Camera

See the open issues for a full list of proposed features (and known issues).

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Contributing

Contributions are what make the open source community such an amazing place to learn, inspire, and create. Any contributions you make are greatly appreciated.

If you have a suggestion that would make this better, please fork the repo and create a pull request. You can also simply open an issue with the tag “enhancement”. Don’t forget to give the project a star! Thanks again!

1. Fork the Project
2. Create your Feature Branch (git checkout -b feature/AmazingFeature)
3. Commit your Changes (git commit -m 'Add some AmazingFeature')
4. Push to the Branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

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License

Distributed under the MIT License. See LICENSE for more information.

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Contact

Your Name - Jeff Higgason - jeffh@opensar.net

Project Link: https://github.com/jhiggason/YahBoomG1Tank

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