Robot is on the ball

CarnegieMellonUniversity researchers have developed a human-size mobile robot that balances on a ball instead of legs or wheels.


“Ballbot” was created by robotics research professor Ralph Hollis. It is a self-contained, battery-operated, omnidirectional robot that balances dynamically on a single urethane-coated metal sphere. It weighs 43kg and is the approximate height and width of a person. Because of its long, thin shape and ability to manoeuvre in tight spaces, it has the potential to function better than robots that currently interact with people.



Hollis is working to prove that dynamically stable robots like Ballbot can outperform their static counterparts. Traditional, statically stable mobile robots have three or more wheels for support, but their bases are generally too wide to move easily among people and furniture. They can also tip over if they move too fast or operate on a slope.



Ballbot has an onboard computer that reads balance information from its internal sensors, activating rollers that mobilise the ball on which it moves, a system that is essentially an inverse mouse-ball drive. When Ballbot is not in operation, it stands in place on three retractable legs.



Future plans for Ballbot include adding a head and a pair of arms. Swinging the arms, said Hollis, would help to rotate and balance the body.



‘We want to make Ballbot much faster, more dynamic and graceful,’ he said. ‘But there are many hurdles to overcome, like responding to unplanned contact with its surroundings, planning motion in cluttered spaces and safety issues.’