Holy s**t, NOW i got seriously jealous:

Lots of respect for the DIY aspect... but I've got a wobbly chair that moves more than that

https://www.youtube.com/watch?v=J3FqpLcheo8&t=207

still driving automatic lol

I like this one the best of all of them.

https://youtu.be/urrow1AV8dE?t=35

Too bad the final version wont have the up/down bumps.