It may be tiny, but it’s mighty. A soft, wearable acoustic sensor that weighs less than a paper clip has been developed by CU Boulder and Northwestern University. This miniature machine can measure the subtlest vibrations in the human body, allowing for the monitoring of human heart health and even the recognition of spoken words.

The stretchable device captures physiological sound signals from the body, has physical properties well-matched with human skin and can be mounted on nearly any body surface, says Jae-Woong Jeong, professor of electrical, computer and energy engineering. The sensor, which resembles a small Band-Aid, can gather continuous physiological data, even catching subtle events like the opening and closing of heart valves, vibrations of the vocal cords and movements in the gastrointestinal tract.

Such sensors could be of use in remote, noisy places, producing quiet, high-quality cardiology or speech signals that could be read in real time by doctors at distant medical facilities, Jeong says.