The TurtleBot 4 and TurtleBot 4 both run diagnostics updater and aggregator nodes by default. The updater records diagnostics data and the aggregator formats it so that it can be used with
rqt_robot_monitor. This is a tool that can be used to monitor various robot topics to ensure that they are publishing data at the expected frequency.
To check that diagnostics are running properly, call
ros2 node list
You should see a node called
turtlebot4_diagnostics. Additionally, calling
ros2 topic list
should list topics such as
/diagnostics_toplevel_state. If diagnostics are not running, you can manually run them by calling
ros2 launch turtlebot4_diagnostics diagnostics.launch.py
Once diagnostics are running, you can view them with
rqt_robot_monitor. Ensure that turtlebot4_desktop is installed on your PC, then call
ros2 launch turtlebot4_viz view_diagnostics.launch.py
The monitor will display any errors in the first window, any warnings in the second window, and a summary of all topics in the "All devices" section at the bottom. Each topic has a status level of OK, WARNING, ERROR, or STALE. There is also a more detailed message included as well. You can click on each topic to view more information.
In this example, the OAK-D node is not running, so the camera topics are not being published.