This week we met with a professor in the mechanical engineering department and asked him to review our gear hub design. Upon first look, he commented that our design was reminiscent of a manual automotive transmission. Automotive transmissions use a piece called a synchronizer (pictured below) to slide back and forth along an axle and engage different gears. Our design utilizes a similar concept. In our most recent prototype we decided to use 4 knob protrusions instead of the many teeth shown on the synchronizer. We learned this week that the teeth would actually be just as durable as the knobs, and would make the shifting much smoother. 

Our meeting also opened our minds to the possibility of utilizing automotive components in our design. These components are much more common and available than bike parts. In the upcoming week, we are going to evaluate the feasibility of using a dual shaft gear box, similar to a manual car transmission. Our goal in doing this is to reduce the cost of our hub by reducing the number of custom components. Meanwhile, we are continuing to search for and contact potential manufacturers.