Dynamo, but no light? Making a circuit board for a bike light.
Half a year ago, Beats bike light broke of old age. His bike has a front hub dynamo but he was left without a working light source. He decided to take things into his own hands and make a energy conversion circuit from scratch.
He wanted to have a smart light that would also act as a brake light: When he decelerates the light becomes brighter to alert drivers. It also had to be as simple as possible. So he chose a lightweight microcontroller and no external sensors. Detecting deceleration is done in software.
The first iteration of the circuit had a few minor issues. The microcontroller got fried because Beat went too fast! But, the second version has been improved and you can see the result below. The code and hardware layout/schematics are on Github.