Double pendulum

(The video is not mine but from You tube)I first saw this thing on a channel called make anything. I thought it was interesting so I tried and make one of my own. Many attempts later I came up with this design a miniaturised version of the one I saw that easily mounts to a wall. To make the swinging motion it uses bearings from a skateboard or you can buy them online two give it a fluid almost hypnotic motion. A cool thing I learned about this toy is that there is no algorithm that can predict t