CLEARPATH Turtlebot4 User Manual page 145

Troubleshooting
Diagnostics
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, /diagnostics_agg, and /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