“I’ve always been fascinated with mechanical flip displays, like the ones used in airports, and mechanical 7 segment displays like those used in old ball game score boards. I came across a project online in which the builder had started putting together a single digit seven segment display which used solenoids controlled by an Arduino to actuate it. I have seen micro servos used in all sorts of robots and bionic arms, so I thought it would be a nice idea to try and actuate a 7 segment display using servos. The Arduino Uno, which I usually use for Arduino projects, only has 6 PWM outputs, so I had to get the Arduino Mega. The Mega has 15 PWM outputs, so it was perfect to duplicate some parts of the code and make a two digit display which could count down from 99 (or up to 99).
Here is a full guide with the Arduino code and the 3D print files to build your own mechanical 7 segment display using an Arduino Mega and 14 micro servos.
This guide assumes that you’ve worked with an Arduino micro-controller before and know the basics of programming an Arduino. If you do not, follow the linked guide for more information on creating and uploading your first sketch.
Here is a summary of the build and a video of the display in action. Continue reading for full step by step instructions along with the code and print files.”