A research team led by Professor Kyung-In Jang of Robotics Engineering collects, analyzes, and diagnoses bio-signals wirelessly transmitted to mobile application from the soft electronic skin. Credit DGIST

A new medical tracking device can attach to the skin and send crucial data to a smart phone application.

Researchers from South Korea's Daegu Gyeongbuk Institute of Science and Technology (DGIST) and Northwestern University have developed a new, electronic skin microsystem that tracks heart rate, respiration, muscle movement and other health statistics.

The microsystem sticks to the skin and transmits data on movement and respiration, as well as electrical activity in the heart, muscles, eyes and brain to a user’s smartphone.

“Combining big data and artificial intelligence technologies, the wireless biosensors can be developed into an entire medical system which allows portable access to collection, storage and analysis of health signals and information,” Kyung-In Jang, a professor of robotics engineering at DGIST, said in a statement. “We will continue further studies to develop electronic skins which can support interactive telemedicine and treatment systems for patients in blind areas for medical services such as rural houses in mountain village.”

The researchers view the system as an improvement over current trackers due to its flexibility, smaller size and the ability to stick the self-adhesive patch—a very soft silicone about four centimeters in diameter—on a patient’s skin.

The new skin tracker—which is wirelessly powered—contains about 50 components that are connected through a network of 250 small wire coils embedded in protective silicon that enables the skin to conform to the body. 

The researchers constructed the coils and sensors in a spider web pattern that ensures uniform and extreme levels of stretchability and bendability in any direction, while also enabling tighter packing of components and minimizing size.

The wire coils are 3D, maximizing the flexibility unlike traditional flat sensors. The coil can also stretch and contract without breaking.

The microsystem is created by stretching the elastic silicone base while tiny wire arcs—comprised of gold, chromium and phosphate—are laid flat onto it.  The arcs are firmly connected to the base at one end of each arc and pop up to form 3D coils when the base is allowed to contract.

According to the study, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality.

“Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors,” the study states.

Along with continuous health monitoring and disease treatment, the electronic skin could be used in soft robotics and autonomous navigation.

The study was published in Nature Communications.