——————<INDEX>———————

출처

Tutorial: ROS2 launch files - All you need to know - Robotics Casual

Tutorial: ROS2 launch files – All you need to know

Introduction

ROS2 launch files are a powerful tool for robotics applications. Instead of starting each process manually, they allow you to start multiple nodes with one command and add logic to your startup sequence. This tutorial will explain everything you need to know about ROS2 launch files.

We will start simple by creating a basic launch file and adding it to a package. Then we will discover launch actions, event_handlers, substitutions and conditions in more detail. Afterwards we will discuss common questions and use cases for ROS2 launch files and at the and of the article you can find a list of all the common actions, event_handlers and substitutions that you can use in your launch file. Sounds good? Let’s get started!

In this tutorial we will discuss

• Getting started with ROS2 launch files
  • Writing a simple launch file
  • Adding the launch file to a package
• Important ROS2 launch concepts
  • ROS2 launch actions
  • ROS2 launch event_handlers
  • ROS2 launch substitutions
  • ROS2 launch conditions
• ROS2 launch file FAQ
  • How to hand over command line arguments to a ROS2 launch file
  • How to find out the launch arguments of a ROS2 launch file
  • How to set arguments for a node in a ROS2 launch file
  • How to include a ROS2 launch file in another launch file
• List of common ROS2 launch actions
• List of common ROS2 launch event_handlers
• List of common ROS2 launch substitution

Note: In ROS2 you can also create launch files in XML and yaml format but for this tutorial we will concentrate on launch files written in Python. This tutorial is for ROS2 Humble.

This is the first article I am writing for ROS2. I started to look into it a few months ago and got stuck on launch files when porting my tutorials so I decided start with a tutorial on launch files. I hope to publish more articles on ROS2 in the future.