This remarkable metal carbide within a hydrogel composite senses, stretches and heals like human skin for use in robotics.
(KAUST electronic skin video)
Smart materials that flex, sense and stretch like skin have many applications in which they interact with the human body. Possibilities range from biodegradable patches that help wounds heal to wearable electronics and touch-sensitive robotic devices.
The material is a composite of the water-containing hydrogel and a metal-carbide compound known as MXene. As well as being able to stretch by more than 3400 percent, the material can quickly return to its original form and will adhere to many surfaces, including skin. When cut into pieces, it can quickly mend itself upon reattachment.
“The material’s differing sensitivity to stretch and compression is a breakthrough discovery that adds a new dimension to the sensing capability of hydrogels,” says first author, Yizhou Zhang, a postdoc in Alshareef's lab.
Although I would ordinarily reference a robot's skin, like the Chemelectric Afferent Nerve-Analogues that permitted a wrestling robot in Roger Zelazny's 1966 Hugo award-winning novel This Immortal, I had another thought.
In his wonderful 1962 story The Thousand Dreams of Stellavista, sf writer J.G. Ballard describes psychotropic houses that are able to reshape themselves at the whim of their owners. The house uses a flexible, sensitive substance called "plastex" to work its wonders:
It was a beautiful room all right, with opaque plastex walls and white fluo-glass ceiling, but something terrible had happened there. As it responded to me, the ceiling lifting slightly and the walls growing less opaque, reflecting my perspective-seeking eye, I noticed that curious mottled knots were forming, indicating where the room had been strained and healed faultily. Deep hidden rifts began to distort the sphere, ballooning out one of the alcoves like a bubble of overextended gum.
"Lively responses, aren't they, Mr. Talbot?" He put his hand on the wall behind us. The plastex swam and whirled like boiling toothpaste, then extruded itself into a small ledge. Stamers sat down on the lip, which quickly expanded to match the contours of his body, providing back and arm rests.
'Of course, you're getting nothing but custom-built units here,' Stamers said. 'The vinyl chains in this plastex were hand-crafted literally molecule by molecule.'
(Read more about plastex)
Scroll down for more stories in the same category. (Story submitted 12/1/2018)