Introduction to ROS Part 9 - Launch Files

Learn how ROS 2 launch files can dramatically improve how you manage and run multiple nodes in your robotic systems through this comprehensive 32-minute tutorial. Discover how to start entire node networks with a single command using launch files written in XML and Python, instead of launching each node individually through the terminal. Begin with a hands-on demonstration of a simple XML launch file that starts a publisher and multiple subscribers, complete with custom parameters, namespaces, and unique node names. Explore how to modify package.xml and CMakeLists.txt to support launch files and use tools like rqt_graph to verify your node connections. Progress to Python-based launch files, which offer more flexibility and logic than XML, and learn how to organize these files in a separate bringup package while configuring your nodes dynamically using YAML parameter files. Master the generate_launch_description() function and understand how it builds a LaunchDescription object that orchestrates the behavior of your nodes. Gain essential skills for declaring launch arguments, substituting file paths, and applying configurations at runtime—all crucial for building scalable ROS 2 systems. By completion, you'll be equipped to automate node orchestration, manage parameters across environments, and build reusable launch infrastructure for your ROS-based robotics projects.