/ros2_pi_gpio

ROS 2 package to control Raspberry Pi GPIO pins

Primary LanguagePython

ROS 2 Raspberry Pi GPIO Control Package

ROS 2 package to control Raspberry Pi GPIO pins

This packages allows you set and read Raspberry Pi GPIO pins via ROS 2 action calls.

Tested with Raspberry Pi3, ROS2 Eloquent, and Ubuntu 18.04 Server

Link to the project video: https://www.linkedin.com/embed/feed/update/urn:li:ugcPost:6654600397346484224

Demo:

1. Build Instructions

source /opt/ros/<ros2_distro>/setup.bash
mkdir <your_ros2_ws_name>
cd your_ros2_ws_name
mkdir src
cd src
git clone https://github.com/mlherd/ros2_pi_gpio.git
cd ..
colcon build --sysmlink-install
source install/setup.bash

2. Usage

  • 2.1 Setup Raspberry Pi

    • Download Ubuntu Server 64-bit
    • Flash the image file on your MicroSD card. I use Etcher on Ubuntu and Rufus on Windows.
    • Default user name is ubuntu and password is ubuntu.
    • Set up WiFi connection. You can skip this step if you want use the eternet port.

      • sudo nano /etc/netplan/50-cloud-init.yaml

      •  network:
     ethernets:
         eth0:
             dhcp4: true
             optional: true
     version: 2
     wifis:
         wlan0:
             optional: true
             dhcp4: true
             access-points:
                 "<Your WiFi Name>":
                     password: "<Your WiFi Password>"
        • Save the file and apply the changes
          • sudo netplan --debug try
          • sudo netplan --debug generate
          • sudo netplan --debug apply

      • Generate SSH Keys

        • sudo ssh-keygen -A

      • Install ROS 2 Eloquent

        • https://index.ros.org/doc/ros2/Installation/Eloquent/Linux-Install-Debians/
        • Make sure you install ROS-Base Install (Bare Bones)

      • Install development tools and ROS tools

        • https://index.ros.org/doc/ros2/Installation/Eloquent/Linux-Development-Setup/

  • 2.3 Edit gpio_pins.txt

    • <pin_id>,<input_output>
    • example:
      • 17,out
      • 18,in

  • 2.4 Run pi_gpio_server

    • You may need to have super user permissions to access GPIO pins
    • sudo su
    • ros2 run pi_gpio pi_gpio_server

  • 2.5 Send goals to the action server

    • example via command line interface:
      • ros2 action send_goal <action_name> <action_message_type> <action_goal>
      • ros2 action send_goal pi_gpio_server pi_gpio_interface/action/GPIO {'gpio: "17,high"'}
      • ros2 action send_goal pi_gpio_server pi_gpio_interface/action/GPIO {'gpio: "18,low"'}
      • ros2 action send_goal pi_gpio_server pi_gpio_interface/action/GPIO {'gpio: "18,read"'}

3. Nodes

  • 3.1 /pi_gpio_server

    • ROS 2 action server node

    • 3.1.1 Actions

      • Action name: pi_gpio
      • Action type: pi_gpio_interface/action/GPIO
      • pi_gpio (pi_gpio_interface/action/GPIO)
        • Goal
          • string gpio
        • Result
          • int32 value
        • Feedback
          • int32 feedback