A robot is a fascinating piece of machinery. They can be programmed to make complex movements over and over again with great precision. Not only can they be fitted with a welding application, but depending on the product that is being produced, they can also have an application for: glueing, measuring, picking, placing and even a combination of those applications.
The LEGO model you are looking at is a small scale robot with a welding application. The robot can move all six of its axes and thus can be moved in many positions. Also included is a robot programmer with a teach pendant that is used for moving and programming the robot.