Electromechanical displays, such as those using flip-dots, are certainly entertaining. Hacker “negermano,” however, wanted to make something all his own, and designed a unique display that uses rotation to reveal the needed dots. The device takes the form of an 8x8 grid of mechanical devices that resemble a propeller on the inside, which twist light material out from under a dark covering as needed. As noted, this setup allows for not just on/off commands, but can reveal colors incrementally for a sort of greyscale display.
While the concept of twisting out each pixel for display is straightforward, implementing it 64 times is not. Printing time for the fixtures took a solid 2 weeks, not including assembly, wiring, and hand-finishing operations needed to perfect the parts. Control is via a Raspberry Pi, assisted by a Pololu Mini Maestro USB servo controllers in order to handle the massive number of servos involved.
While animations aren’t yet implemented, it does have a scrolling display which can be seen in action in the first video. You also can see the back of at work in the video below, or be sure to check out the code and other files if you’d like to examine the build further.