Ok, in truth it's not exactly that, but that's the nickname it got. It's a self-stabilizing platform. It doesn't matter the angle you put the lower platform in, the upper platform will ever stay in the horizontal position. I used the method from this post , by Lauzsus, and adapted to my needs, incl…

Self balancing waiter tray. (or almost it)

system October 13, 2012, 1:59pm 11

What is the name of the sensor ur using?

Nice Project though.
cheers