Errors using robot_monitor

GUI doesn't come up or stays empty

If you see something like:

Unable to register with master node [http://localhost:11311/]: master may not be running yet. Will keep trying.

• Is your ROS_MASTER_URI pointing at the right place?

GUI Turns Gray Frequently

When the robot_monitor turns gray, it means that it doesn't hear from the /diagnostics_agg topic.

• Use rostopic to make sure the topic is still published.

rostopic info diagnostics_agg 

• Listen to /diagnostics_agg to listen to the data.

rostopic echo diagnostics_agg

Try contacting the Master and make sure that you can ping the robot.