I have yet not found a arduino motor controller that would be able to control app. 2x 80W motors so any help from here would be also appreciated.
First I want to know if it is possible making robot to follow phone
Similiar producs have been made (shadow caddy) but the prices are way too much for my budget.
have 1 sensor sending pulse from my beltand have 3 (or more) sensors reading the distance to my belt.
@PaulS:Some of the Devantech SRF0x sensors can be used in "listen-only" mode.A "master" transmitter can send a pulse and the others be commanded to listen for the returns.I can imagine a system using multiple receivers and time-of-arrival to provide rough direction, but as I said, you need to know when the master transmitted (either by RF or optical means) to provide range.
I'm no expert, but could it be possible to send data withing the signal with on-off keying or similiar method?
You could add a cheap 4xxMHz tx/rx pair to the system to provide the sync function.