A team of engineers from Stanford University has achieved a significant breakthrough in the field of wearable technology with their creation of a soft electronic skin that directly communicates sensory information to the wearable tech, surpassing previous iterations that relied on external devices. The Stanford experts have also showcased a spray-on skin capable of understanding hand gestures and a smart bandage that transmits wound-healing progress to a CPU.

While previous electronic skins transferred data to chips or external devices, the soft e-skin developed by the Stanford team converts temperature and pressure sensations into electrical signals suitable for direct communication with the brain. This innovation mirrors the nerve impulses generated when the skin’s nerve endings perceive sensations.

The electronic skin utilizes a triple-layer dielectric design, with one of the layers composed of surgical glove rubber. Electric signals are transmitted through each layer using an organic nanostructure network. Each sensory layer can be customized to cater to specific needs and delicately layered together to mimic the function of nerve receptors in human skin. The official release detailing the innovation explains that each electronic layer is only a few tens to hundreds of nanometers thick, resulting in a composite structure that is less than a micron thick after layering—a remarkable feat considering the average thickness of human hair is around 70 microns.

To handle the fragile nature of the skin patch, a substrate is used to support it, bringing the e-skin’s thickness to approximately 25-50 microns, comparable to the thickness of a sheet of paper, according to Bao, one of the engineers involved in the project.

The engineers aimed to develop a soft integrated circuit that emulates the sensory receptors in the human body while operating at a low voltage to ensure the wearer’s safety. Eventually, they discovered that a mere 5 volts were sufficient to detect external stimuli, such as pressure and temperature changes, akin to real human skin.

This groundbreaking electronic skin is hailed as the first of its kind, seamlessly merging sensory capabilities with the desired electrical and mechanical features of human skin in a durable and flexible form. The team envisions potential applications in prosthetics, where it could provide a realistic sense of human touch.

Their ambitious goal is to wirelessly transmit stimulus signals to a chip implanted within a person’s peripheral nervous system, enabling enhanced control of prosthetic limbs. The Stanford team is currently focused on further enhancing the sensing capabilities of their electronic skin innovation, with the ultimate aim of interfacing with the human brain and other body parts.

Significantly, the same team previously reported a method for printing stretchable circuits on skin-like materials using existing equipment employed in the production of silicon-based chips. This development opens up new possibilities for future advancements in the field of electronic skin technology.

By Impact Lab