Flexible electronic 'skin' may lend robots a sense of touch

Scientists have developed a soft, flexible artificial skin integrated with stretchable electronics that could allow robots to have a sense of touch.
Researchers from University of Houston in the US developed a new mechanism for producing stretchable electronics, a process that relies upon readily available materials and could be scaled up for commercial production.
They created the stretchable composite semiconductor using a silicon-based polymer known as polydimethylsiloxane (PDMS) and tiny nanowires to create a solution that hardened into a material which used the nanowires to transport electric current.
"The work is the first to create a semiconductor in a rubber composite format, designed to allow the electronic components to retain functionality even after the material is stretched by 50 per cent," said Cunjiang Yu, assistant professor at the University of Houston.

Traditional semiconductors are brittle and using them in otherwise stretchable materials has required a complicated system of mechanical accommodations.
That is both more complex and less stable than the new discovery, as well as more expensive.

"Our strategy has advantages for simple fabrication, scalable manufacturing, high-density integration, large strain tolerance and low cost," Yu said.
Researchers created the electronic skin and used it to demonstrate that a robotic hand could sense the temperature of hot and iced water in a cup.
The skin also was able to interpret computer signals sent to the hand and reproduce the signals as American Sign Language, they said.

Artificial skin is just one application, the discovery of a material that is soft, bendable, stretchable and twistable will impact future development in soft wearable electronics, including health monitors, medical implants and human-machine interfaces, researchers said.
"We foresee that this strategy of enabling elastomeric semiconductors by percolating semiconductor nanofibrils into a rubber will advance the development of stretchable semiconductors," researchers said
"It will move forward the advancement of stretchable electronics for a wide range of applications, such as artificial skins, biomedical implants and surgical gloves," they said.
The study was published in the journal Science Advances.