Digital clocks are often made out of a series of 7-segment displays, which light up to represent the needed numbers. Michael Klements’ electromechanical project, however, doesn’t use LEDs, but instead physically flips 3D-printed segments into view with 28 micro servos. 

When in use, each segment’s bright green surface is clearly visible. When “off,” they’re turned to reveal a slim black edge that goes largely unnoticed.

The device is powered by an Arduino Uno, along with a DS1302 RTC module. Two PCA9685 16-channel PWM drivers control the motors directly, and as they run off of I2C, more servos/digits could even be added if needed. 

You can see it all in action below and read more about the timepiece in Klements’ blog post.