Trying to:
roslaunch robot_description empty_world.launch
and get following:
RLException: [empty_world.launch] is neither a launch file in package [robot_description] nor is [robot_description] a launchfile name
The traceback for the exception was written to the log file
Hi @yury.kotlyarov, if you are getting that command from the instructions, then there is probably a sourcing mixup in the terminal you are trying to launch from. You can try sourcing the workspace where the robot_description package is or try in a new terminal.