Although the events that doomed the space shuttle Columbia may never be fully understood, investigators have focused on damage to thermal tiles inaccessible to the astronauts. In the future, says Robert Ambrose at NASA's Johnson Space Center in Houston, crews on the International Space Station or a shuttle might include a robotic repairman.

NASA's "Robonaut" is getting close to realizing that vision. With its human-size palm, four fingers, and an opposable thumb, Robonaut is "phenomenally dexterous," says Alan Peters, a researcher at Vanderbilt University's Center for Intelligent Systems. "It has the best hands of any robot on the planet." This allows Robonaut to use wrenches and other hand tools.

Currently, sensors on a human operator's body translate the operator's movements into the robot's actions. The human sees what Robonaut "sees," thanks to cameras mounted in the robot's head. But mechanical engineer Marcia O'Malley at Rice University is developing a sleeve containing tactile vibrators that will enable the operator also to feel what the robot "feels." The payoff: more accurate control.

This tactile dimension might also let Robonaut learn what jobs should feel like, Ambrose says. This could help the robot become fully autonomous, a goal of research collaborators at the University of Southern California. Robonaut could be headed for space in three years.