Aiming to increase the safety of cyclists, I have designed and constructed a brake light for bicycles.
During the development and construction of my first brake light I discovered the problem that the coaster brake was not waterproof when adding electrical contacts to its inside. Therefore I tried to develop a second brake light based on an acceleration sensor, which was intended to work with any braking system, however, this was not feasible as available sensors were too expensive and not sensitive enough. My third design is controlled by the voltage generated by the bicycle's dynamo. It is very effective and can be connected to all bicycles.
[Note: Acceleration sensors have become inexpensive and more sensitive since this project. Bicycle dynamos are not a legal requirement in Germany anymore.]
