Ground Tracking LED Longboard
Building a ground sychronized, configurable LED lit longboard that creates a "floating on light" effect.
The inspiration
Early in my freshman year of undergraduate, I picked up longboarding as a fun way of quickly getting to class. One night while riding, I had the idea that you could have the look of "riding on light" if leds on the bottom of a board had their pixel movement sychronized to the speed of the board. This project stemmed from that errant thought.
Design
To accomplish this task, a few different modules had to be designed and built. The system hinges around a custom encoder built into one of the longboard wheels. Eight neodynium magnets of alternating polarity were glued into a custom printed assembly bolted securely to the wheel. A pair of hall effect sensors can then detect the rising and falling edges of each magnet to sense both speed (based on time between detections) and direction (based on the offset between the two sensors. This information is fed into a esp8266 based microcontroller that reads the pulses and coordinates the movement of indiviudally adressable LEDs on the bottom of the board. For user control, a button is used to cycle pre-programmed light patterns, a potentiometer controls brightness, and an OLED screen nominally shows your measured speed but also shows the chosen pattern and brightness when it is being changed.
