This is a 7x5 inch table that a steel ball rests upon and is positioned using closed loop servo control techniques.
The ball sits upon a X-Y resistive panel and an Arduino microcomputer allows the steel ball to be positioned to a given X-Y placement. You may or may not know it but to get a ball to rest on any given position requires closed loop control code such as is used in this project.
The demo video shows the ball roll in a square pattern as the setpoints are changed from the program automatically. Any sort of slow movement is possible using this code.