Ultegra DI2 Hacking?

[mgiaro]

hi all,
interested in electronic shifter for the handbike of francesca (a special bike, for wheelchaired people, with arms power), I was thinking about if someone have already investigated the ultegra and the the new wiring system.
More, do you know any devidce that can controlo the DI2 FD (dura ace or ultegra) simply pushing one button (or a two state device)?

we are working on a new bike, possibly for paralympic games in London but in Italy it's difficult to find ideas.
I have seen a job of jeffr that could be perfect for us but sadly fairwheel can't sell it..

I was thinking about using a radio command and a 4 way receiver (12v) to go wireless! Anyone tried?
regarsds
Marco
this is Francesca on her handbike in last worldchampionship

[Oilman]

You don't want to go with tranceivers working on 12V. A DI2 group needs a 2 serial li-ion battery, so the voltage range is between 6.8 and 8.4V.

The Ultegra group is not yet available on the market, so there is no way to find out how it works exactly. The only thing I know is Shimano says it works with CANbus, when this is true it would be complete overkill. But we can expect everything from Shimano when it comes to electronics, the current Dura Ace DI2 uses an extremely strange protocol. One of the problems of the current Dura Ace DI2 is that it takes around 300 ms before the derailleur starts shifting.

You can easily control the DI2 derailleurs with a microcontroller. With the current Dura Ace group you'll need an amplifier after the microcontroller, due to stupid design decisions from Shimano. I hope they also fixed this with the new Ultegra, so only a microcontroller is needed. For anyone with experience in electronics and microcontrollers it is an easy project.