Flexible ‘electronic skin’ patch provides wearable health monitoring anywhere on the body

August 23, 2017

New soft electronic stick-on patch collects, analyzes, and diagnoses biosignals and sends data wirelessly to a mobile app. (credit: DGIST)

A radical new electronic skin monitor developed by Korean and U.S. scientists tracks heart rate, respiration, muscle movement, acceleration, and electrical activity in the heart, muscles, eyes, and brain and wirelessly transmits it to a smartphone, allowing for continuous health monitoring.

KurzweilAI has covered a number of biomedical skin-monitoring devices. This new design is noteworthy because the soft, flexible self-adhesive patch (a soft silicone material about four centimeters or 1.5 inches in diameter) can be instantly stuck just about anywhere on the body as needed — no battery required (it’s powered wirelessly).

Optical image of the three-dimensional network of helical coils as electrical interconnects for soft electronics. (credit: DGIST)

The patch is designed more like a mattress or creeping vine than a conventional electronic device. It contains about 50 components connected by a network of 250 tiny flexible wire coils embedded in protective silicone. Unlike flat sensors, the tiny helical wire coils, made of gold, chromium and phosphate, are firmly connected to the base only at one end and can stretch and contract like a spring without breaking.

Helical coils serve as 3D electrical interconnects for soft electronics. (credit: DGIST)

The researchers say the microsystem could also be used in soft robotics, virtual reality, and autonomous navigation.

The microsystem was developed by an international team led by Kyung-In Jang, a professor of robotics engineering at South Korea’s Daegu Gyeongbuk Institute of Science and Technology, and John A. Rogers, the director of Northwestern University’s Center for Bio-Integrated Electronics. The research is described in the open-access journal Nature Communications.

“We have several human subject studies ongoing with our medical school at Northwestern — mostly with a focus on health status monitoring in infants,” Rogers told KurzweilAI.

Abstract of Self-assembled three dimensional network designs for soft electronics

Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, 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.