A Fabric That Can Hear You? MIT Researchers Create a Sound-Sensing Textile

A novel idea comes in the form of a fabric that can hear you, developed by MIT engineers and collaborators at Rhode Island School of Design. A 10-centimeter fiber is woven into a textile that can translate mechanical vibrations into electrical signals, similar to how human ears function every day.

Wei Yan, a materials scientist at Nanyang Technological University in Singapore, claimed that the new fiber is capable of hearing even the faintest sounds like rustling leaves and a slight change in the rhythm of your heart. Yoel Fink, his supervising author and a materials scientist at MIT, also said that the fabric can store, analyze, and even broadcast the data captured from the surroundings. Even though the concept of audio-sensing textiles has been used before, the previous inventions can only dampen the surrounding sounds. This novel advancement is a fabric that can hear you and every other acoustic sound in your body.

Yan was intrigued by the concept of improving the functionality of fabrics to a much higher purpose. Much like the human eardrum, the textile converts sound waves into electrical signals via vibrations. Their main goal is to help medical institutions to monitor their patients’ health, without the constant need for electrocardiograms (ECG) and echocardiograms (EKG). This can potentially be a cheaper alternative to expensive medical treatments for people with heart or lung conditions.

According to Dr. Mario Garcia, chief of cardiology at Montefiore Medical Center, sound-sensing fabrics can increase the survival rate of medical patients. It can also be used by athletes who undergo intensive training programs to monitor their progress since it can pick up bodily signals and interpret them into health messages. Unlike smartwatches, this textile has a wider scope since it covers more parts of your body, especially the torso down to your feet. Hence, it was termed a “fabric that can hear you.”

“For the past 20 years, we’ve been trying to introduce a new way of thinking about fabrics,” Fink says. The team used piezoelectric materials, woven together with fiber, to capture and convert the signals into electrical ones. The team tested out their invention on a t-shirt, and even after 10 times of laundry, the textile works fine as is. However, the safety of the user might be compromised because the fabric uses electric current. Yan ensured that it will still be similar to your daily clothing that’s comfortable and fashionable. Although Yan’s team has yet to calculate the production cost, he’s certain that it will be minimal. It can range from $15 and $50 on average, depending on the fabric’s color, the material’s composition, and other factors.

It can also act as a self-protective gear because it can monitor the stress level of your heart rate, and has the option to broadcast the data if you fainted on the road. This will notify the people within the vicinity to help you, especially if you’re a person suffering from heart disease. In one of their experiments, they tested the effect of installing two piezoelectric fibers, spaced apart, at the back of the shirt. Grace Noel, one of the co-researcher of Yan, said the results suggested that the wearer can determine the direction where the sound came from. Not only can the fabric hear you, but it might potentially enhance your hearing capabilities.

Moreover, Yan said that the sound-sensing fabric is still a work in progress as they are still trying to figure out the accurate frequency the textile can capture. For instance, separating background noises from the important frequency that can detect your bodily functions. “We can build and formulate algorithms that understand the context of that information. What is the difference between sounds occurring outside a heartbeat? It takes the data and turns it into information,” says Fink. They’re also testing out if the invention can be applied in other technological fields. Furthermore, the invention of a fabric that can hear you was recently published in the journal Nature.