ROS 2 Development Environment Setup

Overview

Setting up a proper development environment is crucial for working with ROS 2 effectively. This lesson will guide you through the process of installing ROS 2, creating a workspace, and configuring your environment to start developing robotic applications. A well-configured environment will help you avoid common issues and ensure smooth development workflows.

Prerequisites

Before installing ROS 2, ensure your system meets the following requirements:

Supported Operating Systems

Ubuntu 22.04 (Jammy Jellyfish) - Recommended for development
Ubuntu 20.04 (Focal Fossa)
Windows 10/11 (with WSL2 recommended)
macOS (with Docker or virtual machines)

System Requirements

At least 4GB RAM (8GB recommended)
At least 10GB free disk space
Internet connection for package installation
Administrative privileges for installation

Recommended Development Setup

A modern computer with multiple cores for efficient builds
Reliable internet connection for package updates
Terminal/shell proficiency (bash, zsh, or PowerShell)

Installing ROS 2

Ubuntu Installation

For Ubuntu users, the recommended approach is to install ROS 2 via Debian packages:

Set up your sources.list

sudo apt update && sudo apt install -y curl gnupg lsb-release
sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key -o /usr/share/keyrings/ros-archive-keyring.gpg
echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/ros-archive-keyring.gpg] http://packages.ros.org/ros2/ubuntu $(source /etc/os-release && echo $UBUNTU_CODENAME) main" | sudo tee /etc/apt/sources.list.d/ros2.list > /dev/null

Update apt and install ROS 2 packages

sudo apt update
sudo apt install -y ros-humble-desktop

Install additional development tools

sudo apt install -y python3-rosdep python3-rosinstall python3-rosinstall-generator python3-wstool build-essential

Initialize rosdep
```
sudo rosdep init
rosdep update
```

Windows Installation (with WSL2)

For Windows users, using Windows Subsystem for Linux (WSL2) is recommended:

Install WSL2 with Ubuntu 22.04
```
wsl --install -d Ubuntu-22.04
```
Follow the Ubuntu installation steps above

macOS Installation

For macOS users, Docker or virtual machines are recommended:

Install Docker Desktop for Mac
- Download from docker.com
- Install and start Docker Desktop
Use a ROS 2 Docker container for development
```
docker run -it --rm ros:humble
```

Sourcing ROS 2 Environment

After installation, you need to source the ROS 2 environment to use ROS 2 commands:

source /opt/ros/humble/setup.bash

To make this permanent, add the following line to your shell's startup script:

For bash:

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

For zsh:

echo "source /opt/ros/humble/setup.zsh" >> ~/.zshrc
source ~/.zshrc

Creating a ROS 2 Workspace

A ROS 2 workspace is a directory where you'll develop and build your ROS 2 packages. Here's how to create one:

Create the workspace directory structure
```
mkdir -p ~/ros2_ws/src
cd ~/ros2_ws
```
Source your main ROS 2 installation (the underlay for your development workspace)
```
source /opt/ros/humble/setup.bash
```
Build the workspace for the first time
```
colcon build
```
Source the workspace
```
source install/setup.bash
```

Using Colcon for Building

Colcon is the build tool for ROS 2 workspaces. It's an improvement over the previous catkin tools:

Basic Colcon Commands

Build the entire workspace:
```
colcon build
```

Build only specific packages:

colcon build --packages-select <package_name>

Build with parallel jobs (faster):
```
colcon build --parallel-workers 4
```
Build with symlinks (faster rebuilds):
```
colcon build --symlink-install
```
Clean build artifacts:
```
rm -rf build/ install/ log/
```

Environment Configuration

Setting Up Your Development Environment

Create a bash alias for sourcing your workspace

echo "alias cw='cd ~/ros2_ws && source install/setup.bash'" >> ~/.bashrc
echo "alias cb='cd ~/ros2_ws && colcon build --symlink-install'" >> ~/.bashrc

Set up ROS 2 environment variables

echo "export ROS_DOMAIN_ID=0" >> ~/.bashrc  # Default domain
echo "export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp" >> ~/.bashrc  # Use CycloneDDS

ROS 2 Environment Variables

ROS_DOMAIN_ID: Sets the ROS domain (0-232), allowing multiple ROS graphs on the same network
RMW_IMPLEMENTATION: Sets the middleware implementation (e.g., rmw_fastrtps_cpp, rmw_cyclonedx_cpp)
ROS_LOG_DIR: Sets the directory for log files
RCUTILS_LOGGING_SEVERITY_THRESHOLD: Sets the minimum severity for logging (DEBUG, INFO, WARN, ERROR)

Verification and Testing

After setting up your environment, verify that everything works correctly:

Check ROS 2 installation:
```
ros2 --version
```
Run a simple example:
```
ros2 run demo_nodes_cpp talker
```

In a new terminal, run the listener:

source /opt/ros/humble/setup.bash
source ~/ros2_ws/install/setup.bash
ros2 run demo_nodes_py listener

Use the ROS 2 CLI tools:

ros2 topic list
ros2 node list
ros2 service list

Troubleshooting Common Issues

Package Installation Issues

Problem: Unable to locate package ros-humble-desktop
Solution: Ensure your sources.list is correctly configured and update apt:
```
sudo apt update
```

Permission Issues

Problem: Permission denied when running ROS 2 commands
Solution: Ensure you're running in the correct environment and have proper permissions

Network Configuration

Problem: Nodes can't communicate across machines
Solution: Check firewall settings and ensure ROS_DOMAIN_ID matches across machines

Best Practices

Use Virtual Environments: Consider using virtual environments for Python-based ROS packages
Version Control: Always use git for your workspace and packages
Documentation: Document your workspace setup for reproducibility
Regular Updates: Keep your ROS 2 installation updated with security patches
Clean Builds: Regularly clean build artifacts to avoid build issues

Learning Objectives

By the end of this lesson, you should be able to:

Install ROS 2 on your preferred operating system
Create and configure a ROS 2 development workspace
Understand and use colcon for building packages
Configure environment variables for ROS 2 development
Verify your setup with basic ROS 2 examples
Troubleshoot common environment setup issues

Overview​

Prerequisites​

Supported Operating Systems​

System Requirements​

Recommended Development Setup​

Installing ROS 2​

Ubuntu Installation​

Windows Installation (with WSL2)​

macOS Installation​

Sourcing ROS 2 Environment​

Creating a ROS 2 Workspace​

Using Colcon for Building​

Basic Colcon Commands​

Environment Configuration​

Setting Up Your Development Environment​

ROS 2 Environment Variables​

Verification and Testing​

Troubleshooting Common Issues​

Package Installation Issues​

Permission Issues​

Network Configuration​

Best Practices​

Learning Objectives​