The Ring Watch

I designed a quirky watch that fits on your ring finger. It doesn’t use hands or any other conventional means to tell time; instead it lights an RGB LED to tell time. The PCB is based on the ATtiny85 8-bit microcontroller and the PCF8523 real-time clock (RTC), and is powered off of a CR2032 type coin cell.

The PCB is mounted on a 3D printed ring that I designed using Onshape.

To turn the device on and off I soldered a push button between the exposed copper pad and the coin cell holder. Upon turning on, the ring flashes a color each for the hour, minute digits, and time of day (AM/PM). This requires the user to memorize a color code, since each color (12 possible colors) represents an integer within 0-11 (12 am -> 11 pm or 12 pm -> 11 am).

Aside from the fact that this is not at all a user-friendly product, the challenge is selecting a color code that is intuitive and easy to memorize over multiple uses. I hope to someday adapt the PCB to display time using regular LEDs in a more intuitive way. Below is a demo video!