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Researchers at Tohoku Gakuin University in Japan have developed a robot that stays balanced on a ball, even when it's pushed or heavy loads are placed on top.
Three independent rotors spin to keep the robot's balance atop the ball, and it can move in any direction, using an "omniwheel" akin to the one under Honda's U3-X.[...]
Dynamically stable robots like this one are better than static bots, which use three or more wheels, researchers say.
They can have smaller bases, allowing them to navigate tight corners. And their omnidirectional abilities allow them to quickly go in any direction without having to turn around.
via Popular Science