Wow, I think it's incredible that LASA as able to pull that off! In most real sumo robot competitions, vacuum pumps are not allowed, because they can give a huge advantage in pushing power. My partner and I were thinking of putting one on when we designed our current robot, but we decided against is for 3 reasons: we didn't have nearly enough mass to spare for a good pump, it would probably limit our speed, and we would have to build an almost airtight skirt around the robot, meaning that if it was wedged up by one corner, the wheels would be lifted up off the ground by the skirt in the other corner. The third reason could have been solved by a system with shocks, I suppose, but we were just too heavy already. Anyway, the fact that LASA has been able to circumvent those problems (or at least the first) is pretty awesome!
harryk, just wondering, how did you beat it? What was the skirt made of? I'm assuming there was one. When you got under one end, did the other end wedge the robot up so the wheels were no longer touching the ground? Also, were they that fast?