September 13, 2010

USA: 'Electronic skin' moves closer to reality

SYDNEY, NSW / Sydney Morning Herald / Sci-Technology / September 13, 2010

Biotech wizards engineer electronic skin that can sense touch, which could soon coat the robots of the future

By Nicky Phillips

ENGINEERS have developed an electronic skin that could one day restore a sense of touch to people with prosthetic limbs.

Built out of nanowires and dubbed the "e-skin", the electronic material is so pressure-sensitive that it mimics the sensitivity of human touch.

"The idea is to have a material that functions like the human skin, which means incorporating the ability to feel and touch objects," said nanotechnologist and research leader, Ali Javey, from the University of California, Berkeley.

To build the skin, the researchers printed small squares of nanowires onto a thin film. Each square of nanowires was integrated with an electric switch, before pressure-sensitive rubber was then placed on top of the film to provide the sensitivity.

Electronic skin, shown here in an artist's image, is a step closer to reality.

In the past, researchers had tried to make artificial skins from organic materials because they were more flexible. But these materials were often very poor conductors of electricity.

Using microscopic nanowires, the researchers have been able to maintain flexibility with a material that is also an efficient conductor.

The skin is also very cheap to produce and requires very low voltage to operate, said the researchers, whose findings are published in Nature Materials.

The e-skin was able to detect pressure from 0 to 15 kilopascals, which makes it sensitive enough to detect small forces such as typing on a keyboard and holding an object.

In the same edition of Nature Materials, another group of researchers have also developed an artificial skin. Instead of using nanowires, the team from Stanford University built their skin out of a flexible silicone material, which also had a high pressure sensitivity.

But the use of either artificial skins with prosthetic limbs is still a way off. Significant advances in the integration of electronic sensors with the human nervous system would be required for the technology to work on people.

But artificial skins could soon be used to give robots a sense of touch. "If we ever wanted a robot that could unload the dishes, for instance, we'd want to make sure it doesn't break the wine glasses in the process," said Associate Professor Javey. "But we'd also want the robot to be able to grip a stock pot without dropping it."

In a report with the findings, chemist John Boland said artificial skins could combine a range of senses, not just touch.

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