Now, a group of engineers from UK-based Cambridge Consultants are taking things a step further. They’ve developed a smartphone-based electronic automatic transmission for bikes.
Unveiled yesterday, the system is controlled by an app on a handlebar-mounted iPhone, and incorporates a stock Shimano Di2 electronic gear-shifting system. Other components include wheel rotation sensors, and a pedaling cadence sensor.
Data is transmitted by the sensors using low-power Bluetooth Smart technology, and is processed by an algorithm on the phone. It compares the rider’s current pedaling speed to their preferred cadence, then instructs the Di2 to shift up or down in order to restore or maintain that cadence. When it detects that the rotation of the wheels has slowed suddenly and significantly (indicating that the rider is stopping or slowing), it shifts to a lower gear.
More at Gizmag.