[Al Skierkiewicz]

One way to think of the response is that the center of motion for each drive wheel is the steering axis of the drive module not the steering center of the robot. With that said, the limiting factors on response are the momentum of the robot (plus weight of the robot and whatever it is attached to) and the friction with the floor, the speed of the steering motors and of course the reaction time of the driver. Since drivers are about the same average age and practice, we can assume the reaction time is under a second and far less than the other factors. Since your scenario generally does not take place at sustained maximum speed, the other factors are dominated by the speed of the steering mechanism and that is very fast in the robots I have seen. Low center of gravity is essential, of course, as these moves would generally lift the drive wheels off the floor or tip the robot over. The Michigan Tech Team had a unique method for crab steering involving three drive wheels (the wheels were the special design to grab in one direction and roll sideways) and they achieved steering by applying different power to each motor. It was very impressive to watch and a very simple design.