by the way... a soccer robot... the ones like the robot soccer championship?

And you are trying to use a controller capable of 50A? the controller itself seems to be larger than the size allowed for the robots...

look in the search button, I have posted sometime ago a code to control a servo motor (futaba s3003 type), but a very simple (forward, bakward, left, right), no acceleration control, full-throttle all time :-)