Originally Posted by Al Skierkiewicz (Post 1569549)

This is common with tank drives and lot's of sticky wheels on the floor. If you must turn in place, have your software reduce the throttle command so that you are never running full power in turns. If you don't have dropped center wheels, a six wheel and many times a four wheel drive will put drive motors in near stall conditions when turning in place.

Originally Posted by rlance (Post 1569508)

Were you able to get it worked out. We had this same issue at our regional and ended up changing the program so that when we wanted to rotate it would alternate approx. every half second between the two motors since we couldn't turn them in opposite directions at the same time. One motor forward...other one backwards...other one forward...other one backwards. We did consider adding motors, but time was not on our side between matches.

The lesson we learned is that we should have driven on carpet in practice.

Originally Posted by Mark McLeod (Post 1568888)

It would be easier to train your human drivers to only attempt to turn while also traveling forward or backwards rather than trying to turn in place.
That takes less energy.

Reducing your wheel diameter would also work, however that would probably mean you couldn't get over some defenses.
The problem started when you probably sized the KOP drivetrain up to 8" diameter wheels thereby increasing your overall drive ratio.