Launch file

As before, the arm_sim.launch.py is used. It was not changed at all. Keep in mind that for simplicity, I am not using any command line parameters in this project. In the same time, launch file can work in one of two modes: with or without state publisher GUI. So to have this GUI active, uncomment it in launch file, and to be able to use the script (see below), comment it out. I do not know why, but script and GUI do not work together.

Running this launch file with joint_state_publisher_gui uncommented, will produce the following:

With joint_state_publisher_gui commented out, the result will be the same, of course, except the window with controls will not show up.