Unlike Roombas and the ASIMO that require specific charging docks to refuel their power, the PR2 uses the standard 3-pronged electrical outlet for its power source.

Although it takes Willow Garage's PR2 58 minutes to complete its mission, it managed to barrel through 8 doors—maneuvering itself around junk scattered all over an office space—and find 9 different electrical outlets to recharge itself. If all the outlets were being used, I wonder if the PR2 is smart enough to figure out how to yank out other plugs for an empty socket. [Willow Glen via Robots.net via Technabob]