A team of researchers from the University of Houston have reported a breakthrough in stretchable electronics by developing a soft, flexible artificial skin giving robots a sense of touch.
Researchers at the University developed a new mechanism for producing stretchable electronics, a process that relies upon readily available materials and could be scaled up for commercial production.
According to the study, rubber electronics and sensors that operate normally even when stretched to up to 50 percent of their length could work as artificial skin on robots. The scientists 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.
"It's a piece of rubber, but it has the function of a circuit and sensors," said Cunjiang Yu, an assistant professor of mechanical engineering at the University of Houston. “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.”
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. Further the researchers stated that the skin also was able to interpret computer signals sent to the hand and reproduce the signals as American Sign Language.
According to the researchers, rubber electronics and sensors have a wide range of applications, and artificial skin is just one such 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.
“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,” researchers said.
The research paper can be found in the journal Science Advances.