RobotHubCourse outline

ROS 2 Lyrical Luth · Lesson 03 of 8

Nodes and topics

Create C++ nodes and exchange streaming data with publishers and subscribers.

Estimated time · 45–75 min

Guided lesson

Work through these steps

  1. 1.

    Source the ROS 2 Lyrical environment in a fresh terminal.

  2. 2.

    Run the nodes and topics inspection commands before creating code.

  3. 3.

    Build only the affected package, then source the workspace overlay.

  4. 4.

    Inspect the ROS graph and verify the result from a second terminal.

Example

Try it yourself

ros2 pkg create --build-type ament_cmake --license Apache-2.0 robot_nodes --dependencies rclcpp std_msgs
colcon build --symlink-install

Practical exercise

Apply the lesson

Create a minimal ROS 2 workspace demonstration for nodes and topics, then prove it works with the ROS 2 CLI.

Before you continue

  • ROS_DISTRO reports lyrical
  • The workspace builds without errors
  • The expected node, topic, service, or action is visible in the graph