Scientists at Carnegie Mellon University have created a robot that balances and moves on a ball, instead of on wheels or legs. The Ballbot is a self-contained, battery-operated, omni-directional robot that balances on a single urethane-coated metal sphere. It weighs 95 pounds and is the approximate height and width of a person. It has the potential to perform than current robots because of its long, thin shape and ability to manoeuvre in tight spaces. Ballbot is equipped with an onboard computer that analyzes balance data from internal sensors. That data then helps produce instructions for activating rollers within Ballbot's ball, a system that Carnegie calls an inverse mouse-ball drive. When the robot isn't moving, it has a kick-stand in the form of three retractable legs.
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Carnegie researchers have so far shown that Ballbot can move around on carpet. The next challenge is to give Ballbot a head and arms that can help rotate and balance its body.

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