guests could rotate and align to form variations of the faces painted on them. I devised a
system where each of the disks has a ring protruding on the back, the bottom of which rolls on
improvised wall hangers with rolling ball bearings and the top of which has a roller chain
attached. The wheels are operated by manipulating a rotary optical sensor which controls an
arduino driving a stepper motor with a toothed gear. The toothed gear rotates the disk either
backwards or forwards.