If you frequent Chinese or Japanese restaurants, chances are you’ve seen a gold-colored cat figurine waving you goodbye, wishing you luck in whatever endeavor you’re about to take on. While interesting, Martin Fitzpatrick had a different idea for one of these devices — also known as a maneki-neko— and turned his into a unique persistence of vision display.
The idea started out as a gadget which would turn on in response to an event, but after what he describes as “over-zealous poking,” he managed to break its internal parts. Rather than relegating this golden cat to the trash can, Fitzpatrick decided to instead fit the kitty’s paw with five LEDs, and have it spin around in 360° as a POV display.
Besides a few new parts jutting outside of the shell, the figurine looks mostly stock, however, inside is a different story. The previous arm movement mechanism is replaced with a small motor and plastic gear, mounted to a block of wood with zip ties. Power is supplied to the lights via a slip ring.
The unit is controlled by a Wemos D1 Mini ESP8266 board, along with a L293D motor driver mounted to a strip of perf board. Wires for the LEDs attached to the spinning paw are first threaded through the arm and then to a breadboard. This is then affixed in a configuration that makes the LEDs look like glowing knuckles, spelling out whatever message you have in mind!