Check Out This DIY Bike Speedometer/Projector

March 20, 2013 | Andy Cush

Brooklyn-based technologist Matt Richardson created this badass dynamic bike headlight, which detects the speed at which you’re riding and projects it onto the street in front of you. In the above video, Richardson explains how he made the device, whipping it together using a speed sensor mounted on the front wheel, a single-board computer called a Raspberry Pi, a projector, and a repurposed cell phone battery charger.

If the practicality of projecting your own speed is lost on you, just imagine what you could do with other types of information. Richardson mentions employing GPS in the future, which could map your route in front of you, and a Reddit user suggests a proximity sensor to detect cars getting too close. It’s like DIY Google Glass for your bike.