Researchers have now created an array of piezotronic transistors using zinc nanowires that can convert mechanical motion into electronic controlling signals. The new transistor array can be used to give robots a "sense of touch" and provide humans with a novel way of interacting with touch screens.

The new touch-sensitive transistors called taxels are better than the currently used techniques for sensing, and are as sensitive as the human fingertip. The arrays have about 8,000 transistors.

The array, built at Georgia Tech, relies on piezoelectricity - an electric charge that accumulates in certain materials such as zinc oxide when it is placed under mechanical stress.

The devices developed by Georgia Tech researchers rely on a different physical phenomenon - tiny polarization charges form when piezoelectric materials such as zinc oxide are moved or placed under strain.

"Any mechanical motion, such as the movement of arms or the fingers of a robot, could be translated to control signals. This could make artificial skin smarter and more like the human skin. It would allow the skin to feel activity on the surface," said Zhong Lin Wang, from the Georgia Institute of Technology and one of the study authors.

"This is a fundamentally new technology that allows us to control electronic devices directly using mechanical agitation," Wang added in a news release. "This could be used in a broad range of areas, including robotics, MEMS, human-computer interfaces and other areas that involve mechanical deformation."

The study is published in the journal Science online.