A Korean research team has developed a sensor modelled on the slit-shaped organs in spiders legs that enable them to pick up even miniscule sounds and vibrations. Among the possible applications of the technology are highly selective speech pattern recognition, infrastructure monitoring and the detection of physiological symptoms through wearable sensors.
The ‘nanoscale mechanical crack-based sensor’ consists of a thin layer of platinum with tiny cracks in it that sits on a flexible sheet of polymer. These cracks deform and stretch with vibrations and changes in pressure and, when electrical current is connected to the platinum layer, changes in conductivity are measured in it as the cracks open and close.
Researchers Daeshik Kang and Mansoo Choi of Seoul National University tested their device first as a sound detector by attaching it to a violin. When the instrument was played the sensor was able to record the harmonic frequency of each note after the readings were translated into digital signals and a spectrogram was produced.
In a second experiment, researchers attached sensors to the necks of 10 volunteers and asked them to say words. The sensors outperformed a microphone in isolating the spoken words clearly even with the addition of background noise.
The research team published their paper in the journal
Nature last week. They say it will be three to five years before the technology hits the market.