[Patrick] decided to make a computer controlled etch-a-sketch. While the idea is not that new, there is always a different way to accomplish a goal. An Arduino is used to control a pair of stepper motors which were sourced for pretty cheap, and even came with their own driver. Next a stand was mocked up using foam board, which helps determine where all the parts should live.
Next was a way to attach the steppers to the knobs, gears would be used and a collet meant for model airplanes was sourced to make the mechanical connection between gear and shaft. With everything set in place via foam board and paper printouts, it is off to get some thin plywood. The plywood is sent though a laser cutter creating most of the stand and gears. Now its all software, a program was whipped up for OSX which converts low res pictures into squiggly lines perfect for the etch-a-sketch to draw on its screen.