[MrForbes]

I can't comment on the code (sorry!) but I'll comment on the driving concept...we are using a small R/C type control, with a tiny 2" steering wheel and trigger type throttle, and a 6wd skid steer chassis. The programming team decided it works well if the steering wheel turns the robot even if the throttle is not touched--it will spin the robot in place when you turn the steering wheel, and the speed it spins will be proportional to how far you steer the wheel. This gives the driver one more way to move the robot, which you lose if you require the throttle to be activated (adding forward motion to your steering).

You might want to think about this, as it could affect your plans. One big advantage of skid steering is that it does let you turn "on a dime".

If you are using Ackermann type steering instead of skid steer, then this would not apply.