This hat has a chasing LED feature thanks to our old friend the 555 timer. [BananaSlug] even built in the option to change the speed at the push of a button.
His design starts out with a costume hat. Each of the 25 LEDs is soldered to a 2×4 hole chunk of protoboard. The LED package is pushed through a slit in the hat, but the protoboard remains on the inside where it can be sewn in place. From there [BananaSlug] soldered one negative bus around the circumference, and an individual positive lead from each module back to the control board. They’re addressed by a set of CD4017 decade counters which are clocked by the 555 timer circuit.
This is a great little analog/logic project and the style is perfect if you’ve got the coat to go along with it.

Filed under: led hacks, wearable hacks