Make Your Own Interactive Flip-Disc Art

Flip-disc displays have been around for a long time, but with the rise of inexpensive, high-resolution display technologies, they largely went the way of the dodo bird. In the hardware hacking community, however, obsolescence is not necessarily a bad word. We love our retro computers, clocks, video game consoles, and radios — and flip-disc displays also have a lot of fans. The low-resolution monochrome display is not right for every job, but the satisfying clicks and mesmerizing patterns created by a changing image make them quite appealing for many applications.

If you are intrigued by flip-disc displays, but are not sure how to get started in creating your own, then creative engineer Kathy Korevec’s guide might be just what you need to get up to speed. Korevec designed and built a large, 84 x 42 pixel display that is meant to be hung on the wall like a piece of art. And aside from showing static images and animations, it is also equipped to interactively respond to voice and video streams captured from the viewer of the display.

The display is made up of a grid of off-the-shelf Alfazeta flip-disc panels. These panels are powered by an ATmega128 microcontroller, and have all of the necessary circuitry to individually control the pixels via an RS-485 interface. Since the display is mechanical, it requires quite a bit of power — 24 volts at 9 amps, which is delivered by a 24 volt, 10 amp Meanwell power supply.

A very slick frame was built using 80/20 aluminum extrusions. The PCB standoffs were directly screwed into these frames, but Korevec notes that a lot of caution is needed with this step. The flip-dot modules are very, very fragile.

After chaining together the separate flip-dot modules and powering them up, it was time to add some intelligence to the system. An NVIDIA Jetson Orin Nano Developer Kit, along with an IMX708 camera and a Waveshare audio board, were added to the build. This makes it possible not only to send the appropriate signals to drive the display, but also to run some powerful machine learning algorithms. With tools like MediaPipe for pose detection, the display can, for example, mirror the actions of a person standing in front of it.

The user interface of a personal project like this is usually lacking. We consider a bare bones system that sends raw commands to the device to be good enough for our own use, but may find that when we return to it years later, we have no idea how to use it anymore. To avoid this sort of problem, Korevec developed a smartphone app that can be used to program the display. This makes it easy to create new artwork, change images, and even start an animation.

This guide will make it much easier to get started with flip-discs, however, it is still an expensive hobby to take on. So unless you are looking to spend two to three thousand dollars on your new display, you might be better off sticking with an LCD. But maybe you could simulate the appearance of the spinning mechanical pixels, and even the sounds, if you go that route? If you give it a try, be sure to post the results on Hackster. We would love to see it!