From the Jetsons' Rosie to Richie Rich's Irona to Robby of Forbidden Planet, we've been promised digital domestics that look and act a lot like . . . a maid. But that isn't going to happen anytime soon, robot experts say. The problem? Today's machines are a long way from having the anthropomorphic qualities-above all, sight-found in human help.

If he´s lucky, when he turns the throttle, his 90 percent hydrogen peroxide will expand to 5,000 times its size and convert to steam that will reach 1,300�F. If he´s lucky, he will then be thrust 30 feet into the air, where he will fly for as long as 30 seconds, all while tethered to a 20-foot safety pole. If he´s lucky, self-taught Mexican rocket scientist Juan Manuel Lozano will someday become one of just a handful of people in history to make an untethered flight with a rocket belt.