A digital clock based on seven-segment displays? Not exciting. A digital clock with seven-segment displays that’s really big and can be read across a football field? That’s a little more interesting. A large format digital clock that uses electromechanical seven-segment displays? Now that’s something to check out.
This clock comes to us by way of [Otvinta] and is a nice example of what you can do with 3D-printing and a little imagination. Each segment of the display is connected to a small hobby servo which can flip it 90°. Mounted in a printed plastic frame, the segments are flipped in and out of view as needed to compose the numerals needed to display the time. The 28 servos need two Pololu controller boards, which talk to a Raspberry Pi running Windows IoT, an interesting design choice that we don’t often see. You’d think that 28 servos clattering back and forth might be intolerable, but the video below shows that the display is actually pretty quiet. We’d love to see this printed all in black with white segment faces, or even a fluorescent plastic; how cool would that look under UV light?
We’re not saying this is the only seven-segment servo clock we’ve seen, but it is a pretty slick build. And of course there’s more than one way to use servos to tell the time.