A wearable vibration sensor for accurate voice recognition

A voice-recognition feature can be easily found on mobile phones these days. Oftentimes, we experience an incident where a speech recognition application is activated in the middle of a meeting or a conversation in the office. Sometimes, it is not activated at all regardless of numbers of times we call out the application. It is because a mobile phone uses a microphone which detects sound pressure to recognize voice, and it is easily affected by surrounding noise and other obstacles.

 

Professor Kilwon Cho of Chemical Engineering and Professor Yoonyoung Chung of Electronic and Electric Engineering from POSTECH successfully developed a flexible and wearable vibration responsive sensor. When this sensor is attached to a neck, it can precisely recognize voice through vibration of the neck skin and is not affected by ambient noise or the volume of sound.

 

Conventional vibration sensors recognize a voice through air vibration and the sensitivity decreases due to mechanical resonance and the damping effect, therefore they are not capable of measuring voices quantitatively. So, ambient sound or obstacles such as a mouth mask can affect its accuracy of voice recognition and it cannot be used for security authentication.

 

In this study, the research group demonstrated that the voice pressure is proportional to the acceleration of neck skin vibration at various sound pressure levels from 40 to 70 dBSPL, and they developed a vibration sensor utilizing the acceleration of skin vibration. The device, which is consists of an ultrathin polymer film and a diaphragm with tiny holes, can sense voices quantitively by measuring the acceleration of skin vibration.

Sourced through Scoop.it from: phys.org