Hearing with skin than ears, a new acoustic skin sensors

The newly developed microphone demonstrates a wider auditory field than human ears, while it can be easily attachable to the skin with surprisingly small and thin size. This academic achievement was recently presented as the inside back cover paper in Advanced Materials, an international journal on materials.

Researchers developed a microphone that detects sound by applying polymer materials to microelectro-mechanical systems (MEMS), The conventional microelectro-mechanical systems -based microphones used in cellular phones, Bluetooth devices, and others consist of thin, small and sophisticated diaphragm structures. Being made of rigid and brittle silicon, however, it is difficult to bend the diaphragm or microphone as desired and it interferes with the sound detection ability of the device.

According to the study, the auditory sensitivity of the microphone is higher than human ears, while recognizing the surrounding sounds and voice of the user without distortion. Furthermore, it can detect both loud sounds over 85 decibels, a range that causes auditory damage, and low-frequency sounds that humans cannot hear.

The quality of voice detection is comparable to cellular phone or studio microphones. When the acoustic sensor on the skin was connected to a commercial voice assistant program (Google Assistant), the user could search, translate and control devices effortlessly.

The new acoustic sensor has potential applications in wearable voice recognition devices for the Internet of Things (IoT) and human-machine interfaces. The research team plans to create auditory electronic skin by integrating it with skin-attachable pressure and temperature sensors, flexible displays, and others concluded the authors.

Reference: Siyoung Lee,Junsoo Kim,Hajung Roh,Woongji Kim,Sein Chung,Wonkyu Moon,Kilwon Cho; 22 February 2022 https://doi.org/10.1002/adma.202109545.