A Design Challenge Eliminates the Chain

Meet the ALPHA bike, a fully functional concept bike created by 5 seniors studying Mechanical Engineering at the University of Pennsylvania.
Originally started as a design challenge to push the boundaries of integrated systems design, the ALPHA bike’s mechanics are almost completely internal — and there is no external drive chain.

The front hub of the bike houses a standard dynamo hub with a drum brake. As the bike travels, energy created from the front hub illuminates integrated rear LEDs and simultaneously charges two super capacitors used to power the system which is made up of multiple sensors, an M1 microcontroller, and an inertial-measurement device.

Read the specifics here. This is some impressive work.