3. ROS 2 API

The controller exposes its data and functionality to ROS 2 nodes through topics and services. Nodes running on the robot, for example dockerized nodes, and nodes on the same network can subscribe to the topics and call the services.

The following sections list what is available:

• Topics and Services lists the topics the controller publishes and subscribes to, and the services it provides, together with their message types and QoS settings.

• Application and Logic Program Variables describes the topics and services that are used to read and modify application variables, and the format of the JSON data they exchange.

Topic and service names are prefixed with the robot namespace, see ROS 2 Namespace. The message types are described in URinterfaces Message Library.

• 3.1 Topics and Services
• 3.2 Application and global Logic Program Variables