ROS error messages

Sometimes ROS can give you really detailed error messages that you struggle to fix as a beginner.

The first thing to try is roswtf. This command will run checks on your system to try find any problems (warnings and errors).

Here is a non-exhaustive list of how to decipher some typical ROS error messages:

• Error when using roscd: roscd: No such package/stack 'beginner_tutorials'. This happens when the environment for the particular workspace/package you’re using isn’t available. To fix this, try the following
  • cd ~/directory/pointing/to/my/workspace
  • source devel/setup.bash
• Error when using rosrun: [registerPublisher] Failed to contact master at [localhost:11311].  Retrying... To fix thus start the master
  • roscore

Gazebo error messages

When running Gazebo from the command line, make sure to turn on verbosity in order to show any error or warning messages. Here is a non-exhaustive list of how to decipher some typical Gazebo errors:

• Error when running a plugin: [Err] [Plugin.hh:165] Failed to load plugin lib[plugi-name]_plugin.so: lib[plugin-name]_plugin.so: cannot open shared object file: No such file or directory. To fix this, make sure the correct
• library paths are included:
  • export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:[path-to-plugin-build-directory]
gazebo --verbose [path-to-plugin .world file]