Sensitive touch for Electronic 'Robot Skin'

Scientists have developed a pressure-sensitive electronic skin which could one day be used to restore touch by patients who have prosthetic limbs.This e-skin is made of semiconductor nanowires that operate using very low voltage. It is the first such material made out of inorganic single crystalline semiconductors. The skin can be applied by rubbing it or rolling it onto a surface and can detect pressure around 0 to 15 kilopascals, which would allow a robot helper, for instance, to do the dishes or handle a pet without causing damage.
                 

                                                           

The Butterfly Touch
At the same time scientists from Stanford University have developed an electronic sensor that it is so sensitive that it can feel a touch as light as a butterfly, manufactured in large sheets, the sensors could be used in artifical electronic skin for robots, touch screen displays, automobile safety and a range of medical applications.
The speed of compression and rebound of the rubber are critical for the sensor to be able to detect and distinguish between separate touches in quick succession.

Automobile safety could also be enhanced. "If a driver is tired, or drunk, or falls asleep at the wheel, their hands might loosen or fall off the wheel," said Benjamin Tee, graduate student in electrical engineering and a coauthor. "If there are pressure sensors that can sense that no hands are holding the steering wheel, the car could be equipped with some automatic safety device that could sound an alarm or kick in to slow the car down. This could be simpler and cost less than other methods of detecting driver fatigue."

The UC Berkeley engineers used an innovative fabrication technique that deposits nanowire 'Hairs'.The researchers started by growing the germamium/silicon nonowires on a cylindrical drum, which was then rolled onto a sticky substrate.

John Boland, a nanotechnologist from Trinity College Dublin praised the two approaches in a critique for Nature Materials.It is the most remarkable aspect of these studies is how they elegantly demonstrate that it is possible to exploit well-established processing technologies to engineer low-cost innovative solutions to important technical problems.