A prototype stick-on sensor that not only monitors your heartbeat, but also recognizes spoken words has been developed by a team of researchers at University of Colorado Boulder and Northwestern University.
The study that led to the development of the tiny, soft and wearable acoustic sensor prototype has been published in Science Advances. According to the team behind this sensor the stretchable device, which resembles a small band-aid, is capable of capturing physiological sound signals from the body, has physical properties well-matched with human skin and can be mounted on nearly any surface of the body. The sensor has almost no weight at all and is capable of continuously gathering physiological data, the researchers reveal.
Researchers say that the sensor is very thin and soft and has skin-like characteristics because of which it has the unique ability to ‘listen in’ on the intrinsic sounds created by vital organs of our body, including the lungs and heart. This particular ability of the sensor allows scientists to continuously monitor physiological health.
The researchers say the new device can pick up mechanical waves that propagate through tissues and fluids in the human body due to natural physiological activity, revealing characteristic acoustical signatures of individual events. They include the opening and closing of heart valves, vibrations of the vocal cords and even movements in gastrointestinal tracts.
The sensor can also integrate electrodes that can record electrocardiogram (ECG) signals that measure the electrical activity of the heart as well electromyogram (EMG) signals that measure the electrical activity of muscles at rest and during contraction.
While the sensor was wired to an external data acquisition system for the tests, it can easily be converted into a wireless device, researchers say. Such sensors could be of use in remote, noisy places – including battlefields – producing quiet, high-quality cardiology or speech signals that can be read in real time at distant medical facilities. Check out the video below:
Talking to machines
Vocal cord vibration signals also could be used by the military personnel or civilians to control robots, vehicles or drones. The speech recognition capabilities of the sensor also have implications for improving communication for people suffering from speech impairments.
As part of the study, the team used the device to measure cardiac acoustic responses and ECG activity –including the detection of heart murmurs – in a group of elderly volunteers at Camp Lowell Cardiology, a private medical clinic in Tucson, Arizona collaborating with the University of Arizona, a project partner. The researchers also were able to detect the acoustical signals of blood clots in a related lab experiment.
The sticky, flexible polymer encapsulating the tiny device is stretchable enough to follow skin deformation, said study first author Yuhao Liu, who earned his doctorate and the University of Illinois-Urbana Champaign and now works at Lam Research, headquartered in Fremont, California. The device contains a tiny commercial accelerometer to measure the vibration of the body acoustics and allows for the evaporation of human sweat.
The researchers also showed vocal cord vibrations gathered when the device is on one’s throat can be used to control video games and other machines. As part of the study a test subject was able to control a Pac-Man game using vocal cord vibrations for the words “up,” “down,” “left” and “right.”
The study also included the Eulji University College of Medicine in Korea.