[jimfortytwo]

Don't fool yourself-- a 130 pound robot on a hovercraft is not going to be any easier to accellerate or stop than a 130 pound robot on a good cart. Its still a lot of mass to get moving. Also, it will be harder to steer. If you consider a pull-wagon, if you want to turn you just walk in a small arc and the cart follows behind you. The lateral friction of the tires helps you turn. With a hovercraft, if you want to turn 90 degrees you'll first have to stop its motion in the original direction, and then get it started again in the new direction. Our team build our carts with 8" outdoor pneumatic tires... its a smooth ride over almost anything.