Wearable health tech takes a giant step further with stretchable devices that can attach to the skin. Researchers from Northwestern University and the University of Colorado Boulder, in conjunction with other institutions, have developed a tiny, soft, wearable acoustic sensor that can act like a wearable stethoscope.

The initial applications for the device include measuring heart health, speech recognition, and human-machine interfaces. The wearable chip is about the size of a small band-aid and weighs less than one-hundredth of an ounce. The sensor is encapsulated with a sticky, flexible, stretchable plastic that allows for sweat evaporation. The sensor itself is a small commercial accelerometer that measures acoustic vibrations. The device can monitor mechanical waves through body fluids and tissues, detecting not only the opening and closing of heart valves and vocal cord vibrations but also movements in gastrointestinal tracts. With additional integrated electrodes, the wearable microchip could monitor electrocardiogram (ECG) and electromyogram (EMG) signals.

During the research testing, the sensor relayed data by wire, but could easily be converted to wireless, according to Jeong. Various application possibilities would then open up for use in noisy, remote place such as battlefields, where quiet speech or physiological data could be detected in distant locations. “Using the data from these sensors, a doctor at a hospital far away from a patient would be able to make a fast, accurate diagnosis,” said Jeong. “The thin, soft, skin-like characteristics of these advanced wearable devices provide unique capabilities for ‘listening in’ to the intrinsic sounds of vital organs of the body, including the lungs and heart, with important consequences in continuous monitoring of physiological health,” said John Rogers, director of Northwestern’s Center for Bio-Integrated Electronics.