5. Writing Nodes

In Chapter 3, we explored important concepts such as nodes and topics. In this chapter, we will delve deeper into these ideas by learning how to write nodes. As a refresher, nodes are independent processes that perform specific computations. One of the core functionalities of nodes in ROS2 is to compute some information, publish it to a topic, and allow another node to subscribe to that topic and use the information for further computation. This model of behavior is known as the publisher-subscriber model. In this chapter, we will learn how to write nodes that follow this model, along with exploring additional concepts.