🐶 ROS 2 Initial Setup for Raspberry Pi 4

📝 Introduction

After setting up your Raspberry Pi in headless mode, the next step for robotics projects is installing ROS 2.
ROS 2 is a framework used to build robot applications, such as sensor processing and movement control.
In this guide, you will:

• Install ROS 2 on Raspberry Pi 4
• Set up the environment
• Run a simple test to confirm everything works

This tutorial focuses on a minimal, working setup for beginners.

By the end of this guide, you will have a working ROS 2 environment on your Raspberry Pi and confirm that nodes can communicate.

⚠️ Before You Start

Make sure your Raspberry Pi is already set up and accessible.
✅ You should have:

• Raspberry Pi OS (64-bit) installed using Raspberry Pi Imager
• Wi‑Fi configured (your Raspberry Pi already knows how to connect to your Wi‑Fi network)
• VNC or SSH working

👉 If not, follow this guide first:
🐶 Raspberry Pi 4 Initial Setup (Headless + VNC)
https://qiita.com/tri-edge/items/df545c0aaac6975101ed

💡 How to access your Raspberry Pi

You can use either:

• VNC (desktop GUI)
• SSH (terminal only)
  Example:

ssh [e-mail]

👉 All commands in this tutorial are run in the terminal.

🔧 Requirements

🔌 Hardware

• Raspberry Pi 4 (4GB recommended)
• microSD card (32GB recommended for ROS 2)
• Stable power supply (5V / 3A)

💻 Software

• Raspberry Pi OS (64-bit recommended)
• Internet connection
• Terminal access

※All commands in this tutorial should be run on the Raspberry Pi (via VNC or SSH).

🚀 Setup

① Update your system

sudo apt update
sudo apt upgrade -y

👉 This ensures your system is up to date.

② Set locale (required)

sudo apt install locales -y
sudo locale-gen en_US en_US.UTF-8
sudo update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8

Using Raspberry PI terminal, check:

locale

👉 You should see en_US.UTF-8

③ Add ROS 2 repository

Install required tools:

sudo apt install software-properties-common curl -y

Add ROS 2 key:

sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key | sudo apt-key add -

Add repository:

sudo sh -c 'echo "deb http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main" > /etc/apt/sources.list.d/ros2.list'

Update packages:

sudo apt update

④ Install ROS 2

✅ Recommended (lightweight)

sudo apt install ros-humble-ros-base -y

👉 Best option for Raspberry Pi RoboDog

⑤ Set up environment

echo "source /opt/ros/humble/setup.bash" >> ~/.bashrc
source ~/.bashrc

✅ This enables the ros2 command

⑥ Install build tools

sudo apt install python3-colcon-common-extensions -y

✅ Test ROS 2 installation

🖥️ Open two terminals

Terminal A:

ros2 run demo_nodes_cpp talker

Terminal B:

ros2 run demo_nodes_py listener

Expected result

• Terminal A → sending messages
• Terminal B → receiving messages

Example:

I heard: Hello World

✅ This confirms ROS 2 is working

🧠 What is ROS 2?

ROS 2 uses a publisher / subscriber system:

• Talker → sends data
• Listener → receives data

👉 This is how robot components communicate

⚡ Key Points

• Use Raspberry Pi 64-bit OS for compatibility
• Install ros-base for better performance
• Run source ~/.bashrc if commands don’t work
• ROS 2 needs two terminals to test communication

✅ Summary

You now have a working ROS 2 setup:

• Installed ROS 2
• Configured environment
  👉 ROS 2 commands are available in the terminal
• Verified communication
  👉 Confirmed that ROS 2 nodes can send and receive messages

✅ Your Raspberry Pi is now ready for robotics development using ROS 2

🚀 You are now ready to start controlling hardware and building your robot dog using ROS.