https://www.youtube.com/watch?v=ygcGfnVM6Ho
It would be a lot of fun if someone programed up an electronic version of this where you select the wheels and distances and layout the machine to make electronic cycloids that you then send to your glow in the dark setup. This is too complex for real time image production any other way. Sure this type of image is done all day in abstract programs but not in THIS way as a simulation of a mechanical system. This is just fun and cool. Ok you programers have at it.
BRAD this is your fault you sent me down the rabbit hole with those sand tables.....