Australian Cycling Forums - Bicycles Network Australia

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.

Andrew

My fingers have been doing that for decades.

Quite interesting - natural that someone would do this.

Race cars eventually did get it for a short time until banned (experimental Peugeot 905 Evo.2). I'd like to try this kind of system out of curiousity. I am interested in the technology.

But still,many will prefer manual shifting because that's how they've done it always.

The only reason I don't think that I would like it is because I don't have an optimal cadence for all types of riding. For example if I'm climbing out of the saddle I don't want to be forced into a gear for 100rpm like I'd normally want.

Strange, but I just have no desire to mount my phone on the handlebars of my bike

man, just think of the potential this could have! think of the data input this thing could have: speed, cadence, gradient, heart rate and power. but then, as the phone will have access to (hopefully accurate) map data it could preempt the ride, for instance as you get to the bottom of a hill it could move to the small chain ring while you arent hammering the pedals. then while you are climbing maybe it could even guess your position (standing or sitting) based on cadence and power output and put you in a higher gear accordingly.

this definitely makes me want Di2! (even if it is just for geek value)