Bipedal robots presented based on old-style toys, simple mechanics

Robot Denise walks in a science center in Dutch, The Netherlands, next to Dutch researcher Wisse on February 17. Denise is the first two-legged Robot that can move on a flat floor with a minimum of electronics and bottles carbon dioxide gas. PHOTO: AFP

Footage of three robots was shown at the American Association for the Advancement of Science annual conference here in Washington. The robots shown operate by using force of gravity, their legs acting like a double pendulum.

Small electric motors fed by an extremely low voltage battery act as joints, allowing the robots to control their steps and adapt to irregularities in the terrain.

"We can let the mechanics take care of a lot of the motion as opposed to motors," said Andy Ruina, of New York's Cornell University, creator of one of the robots.

"The concept is simple, the legs act like sticks attached to hinges and swing back and forth with a pendulum motion" -- a concept used for more than 100 years in design toys that walk down a slope without propulsion.

Another biped designed by Martijn Wisse of Delft University of Technology in the Netherlands has a pneumatic system that simulates the way leg muscles work.

The third robot, based on the same principle, was presented by researcher Russ Tedrake of the Massachusetts Institute of Technology in Boston.

His model, dubbed "Toddler" is more computer-based, allowing it to walk on its own,

"It can walk on a variety of terrains. It evaluates how to walk and adjusts."

All three robots use very little power to operate.

Use of the experimental machines involved development of more sophisticated and efficient artificial legs, researchers said.

"If we understand how humans move, we can develop more advanced rehabilitation," said Tedrake.