[Binome]

Your definitly up for a challenge, if you want to use a USB mouse as a position sensor.

You are going to most definitly need an external co-processor, with a USB host chip, and appropriate firmware to decode the HID stream from the mouse to something the RC can understand, like a simple TTL serial stream.

If you can get a hold of some ps/2 mice, it can make your job MUCH easier, and you can easily decode ps/2.

Good luck!