Cephalopod skin, such as that of octopuses, squids, and cuttlefish, is stretchy and intelligent, contributing to their ability to sense and respond to their surroundings. These properties have been harnessed by a Penn State-led collaboration to create an artificial skin that mimics both the elasticity and neurologic functions of cephalopod skin, with potential applications in neurorobotics, skin prosthetics, artificial organs, and more.
The team’s findings were published in the Proceedings of the National Academy of Sciences, led by Cunjiang Yu, Dorothy Quiggle Career Development Associate Professor of Engineering Science and Mechanics and Biomedical Engineering.
Our recently developed soft synaptic devices have achieved brain-inspired computing and artificial nervous systems that are sensitive to touch and light that retain these neuromorphic functions when biaxially stretched.
Cunjiang Yu
The skin of cephalopods is a soft organ that can withstand complex deformations such as expanding, contracting, bending, and twisting. It also has cognitive sense-and-respond functions, which allow the skin to detect light, react, and camouflage the wearer. While artificial skins with either physical or cognitive capabilities have previously existed, according to Yu, none have exhibited both qualities at the same time–the combination required for advanced, artificially intelligent bioelectronic skin devices.
“While several artificial camouflage skin devices have recently been developed,” Yu said, “they lack critical noncentralized neuromorphic processing and cognition capabilities, and materials with such capabilities lack robust mechanical properties.”
“Our recently developed soft synaptic devices have achieved brain-inspired computing and artificial nervous systems that are sensitive to touch and light that retain these neuromorphic functions when biaxially stretched.”
The researchers built synaptic transistors entirely out of elastomeric materials to achieve both smartness and stretchability. These rubbery semiconductors function similarly to neural connections, exchanging critical messages for system-wide needs while remaining impervious to physical changes in the system’s structure.
According to Yu, the key to developing a soft skin device with both cognitive and stretching capabilities was to use elastomeric rubbery materials for every component. This approach resulted in a device that can successfully exhibit and maintain neurological synaptic behaviors like image sensing and memorization even when stretched, twisted, and poked 30 percent beyond its natural resting state.
“With the recent surge of smart skin devices, incorporating neuromorphic functions into these devices opens the door for a future path toward more powerful biomimetics,” Yu explained. “This methodology for incorporating cognitive functions into smart skin devices could be extended to many other areas, such as neuromorphic computing wearables, artificial organs, soft neurorobotics, and skin prosthetics for next-generation intelligent systems.”
This research was funded by the Office of Naval Research Young Investigator Program and the National Science Foundation.
