I had the idea to make a gigantic perler bead mural right after grad school. I just didn't have the time to do it. So I let the idea go, and every once in a while it would come back to me. 3 years later I decided to make it happen. I spent a month nagging my coworker, Hector, for resources and tips, digging into physics, and researching mechatronics before getting my hands dirty.
The result of a few months of work was the Big PP. It's made up of 2 ink jet printers, 1 DVD drive, 3 stepper motors, 3 stepper motor drivers, 1 servo, 1 Arduino Uno, 1 Arduino Nano, 1 gem grabber, wood, lots of glue, blood, and sweat (seriously).
It's still in development, but I entered it into Firstborn's annual art show to do a little stress testing. I attached a pen to DVD drive mechanism and let people use the debugging joysticks to draw pictures using the contraption.