Matchew,
I'm confused about your setup. Do your wheels turn (left and right) or are you using differential speed (skid steer) to turn you robot?
If you have true quad steering (left and right) then you will need position feedback so the BS program will know where the wheels are pointing. Then a control loop will need to be programmed. (see
White Papers ) for control loop programming.
Good Luck
Tim Tedrow