Rock and Roll In an ongoing attempt to make computer engineering just that much sexier, the creators of the Robot Races have hit upon a sure-fire new crowd-pleaser: International Robot Sumo Wrestling. The Robot Races, and the Robot Wars held at Fort Mason, have inspired tinkerers of all ages and skill levels to create machines that can compete with, and potentially destroy, other machines. They've entered from as far away as France, and given their creations names worthy of monster trucks -- like Thor and the Mulcher. The sumo wrestling competition pits 10 champion Japanese robots and their makers against 10 American counterparts. Robots, in light- and regular-weight categories, must try to force or trick their opponents out of the 1-meter ring, relying on the data they "absorb" to make "decisions." The competition begins at 12:30 p.m. at the Exploratorium, Bay & Lyon, S.F. Admission is free-$9; call 561-0363.