New York, Jan 18 IANS | 6 months ago

Humans have been walking on earth for over a million years and researchers are now close to figuring out how they do it.

A research published in the Journal of Experimental Biology outline a specific interaction between the ankle, knee, muscles and tendons that improve the understanding of a leg moving forward in a way that maximises motion while using minimal amounts of energy.

"Human walking is extraordinarily complex and we still don't understand completely how it works," said Jonathan Hurst, professor of mechanical engineering at Ohio State University (OSU) in the US.

Researchers have long observed some type of high-power 'push off' when the leg leaves the ground, but did not really understand how it worked.

The study concluded that there are two phases to this motion.

The first is an 'alleviation' phase in which the trailing leg is relieved of the burden of supporting the body mass.

Then in a 'launching' phase, the knee buckles allow the rapid release of stored elastic energy in the ankle tendons, like the triggering of a catapult.

"We calculated what muscles could do and found it insufficient, by far, for generating this powerful push off," said Daniel Renjewski, a postdoctoral research associate in the dynamic robotics laboratory at OSU.

The research could find some of its earliest applications in improved prosthetic limbs, said researchers.

Walking is almost like passive falling. The robots existing today do not walk at all like humans as they lack that efficiency of motion and agility, the study added.

"When we fully learn what the human leg is doing, we would be able to build robots that work much better," said Hurst.

We still have a long way to go before walking robots can move with as little energy as animals use. But this type of research would bring us closer to that, the study said.

(Posted on 18-01-2014)