The ME14 transmission project is an annual competition that takes place over two weeks near the end of sophomore year for mechanical engineers at Caltech. The goal of this project is to design a gearbox which efficiently couples a small DC motor with a bicycle wheel. The score is the max RPM divided by the time to accelerate to 250 RPM.

What makes our gearbox unique

Our gearbox is a unique shifting gearbox. We chose to use a dual roller clutch shifter, so that the ratios can be changed while running, based on the input direction. This is the first application of a roller clutch based shifter in this competition. Two ratios gives a great advantage in score potential as one ratio maximizes RPM, while the other minimizes the time to reach 250 RPM. Generally a shifting gearbox would be too complex and expensive to implement within our constraints. However, our innovative solution has no moving shifter parts other than the rotation of the gears themselves.

Critical Design Review

Final Design Debrief