Moritz von Sivers' Clever Lenticular Clock Turns Angular Shifts Into Time-Telling
This interesting take on a mechanical clock controls the viewing angle of lenticular "seven-segment" modules using hobby servos.
Physicist, maker, and self-described electronics enthusiast Moritz von Sivers has designed a clock that uses lenticular lenses and shifting angles to display its digits.
"Lenticular animations are based on several interlaced pictures viewed through an array of cylindrical lenses. The individual pictures can then be distinguished by changing the viewing angle," von Sivers explains. "You probably have seen this effect before, e.g. on post cards. I remember having a ruler in primary school with a picture of dinosaurs on it that changed depending on the viewing angle. My idea was to create a clock that uses lenticular animations to display the time."
At first glance the clock appears to use seven-segment display modules, though in physically-separated sections that resemble a split-flap or similar mechanical display. While the numbers, hours at the top and minutes underneath, do indeed use a seven-segment pattern, there's no electronics inside — and no moving parts per module, either.
Instead, the segments are printed in such a way to line up with the ridges on lenticular lenses installed in the front of each module — meaning that the visible segments will depend on the angle at which you're viewing the clock. To actually display the time, a quartet of hobby servos physically tilt each module independently under the control of an Espressif ESP8266 module.
"At first, the positions of the motors that correspond to the correct tilt angle for each digit need to be specified in the servo.h file," von Sivers explains. "For that I viewed the clock from a defined angle and controlled the servo positions via the serial monitor in the IDE. When the code is first uploaded, the ESP8266 opens an access point and lets you enter your Wi-Fi credentials. It then connects to your local Wi-Fi and synchronizes the time via NTP [Network Time Protocol]."
The project is documented in full on von Sivers' Instructables page; source code and 3D print files have been published to GitHub under a Creative Commons Attribtion-NonCommercial-ShareAlike 4.0 International license.