Light-Up Spinning Clock

Making your own clock is a favorite pursuit among hackers, and creator Ludwin has morphed several technologies together to produce his own unique timepiece. This humbly named Rotating LED Display spins a CD-sized disk PCB, with 40 LEDs that blink images to life on its surface via persistence of vision.

The spinning PCB disk mounts an Arduino Nano, along with five shift registers for direct control of the LEDs. An ESP-01S ESP8266 module connects to the Internet to get time/date/weather information, and generates a local webpage for the user interface. The ESP-01 also translates stored images and/or data into the proper blinking pixel sequence, which is transmitted to the Arduino Nano via I2C.

A Hall effect sensor keeps the LEDs clocked. This is especially important here, as two (nearly) mirrored rows of 20 LEDs are arranged sequentially to fill in any visual gaps as it spins.

LEDs, along with shift registers and other “dual components,” are arranged symmetrically along a centerline to balance the spinning disk’s weight. Non-symmetrical components, such as the Arduino Nano and ESP-01S, are arranged directly on this centerline, with screw-and-nut counterweights added to keep it balanced.

Under the display board, the device mounts its power supply, as well as the driving CD motor. Speed is tuned via an onboard potentiometer. To transfer power to the top disk, a coil is constructed on the base/power PCB, and on a third PCB that attaches to, and rotates with, the display board.

It’s quite a clever and well-refined build, outlined in the video below. Details are available on GitHub if you'd like to examine things further or make your own.