It Keeps Going, and Going...

This robot is no push-over. If you try to knock it over, it steps forward and regains its balance - just like a human would.

This robotic pair of pants is called RABBIT. The University of Michigan and French scientists have been working on it for more than six years, and late last year, it took its first six steps. Now it walks gracefully and is the first known robot to walk and balance much like a human.

Other bipedal robots - or two-legged walking machines - in existence today walk flat-footed, with an unnatural crouching or stomping gait, and have large boxy feet, said UM researcher Jessy Grizzle. RABBIT was built without feet. Its legs end like stilts so that it pivots on a point when it moves forward.

"If you build a robot that pivots on a point you must understand how the different parts interact dynamically, or else it will fall over," Grizzle said. If a robot has no feet, it's impossible to "cheat."

Grizzle, who developed the control theory for the robot, said that the balancing ability programmed into the robot has many applications in the medical field, such as so-called smart prosthetics that adapt to the wearer, and physical rehabilitation aids to help people regain the ability to walk. Other applications include rehabilitative walking aids for spinal injury patients, machines designed for home use that can climb stairs or robots for use in exploratory missions over rough terrain.

RABBIT is part of France's ROBEA project (Robotics and Artificial Entity), which involves seven laboratories and researchers in mechanics, robots and control theory. The machine is housed in France's Laboratoire Automatique de Grenoble,

The U-M/French control theory for walking was published in a recent paper in the International Journal of Robotics Research.

Click here to view videos of the robot walking and regaining its balance.

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