earing aids could one day get an upgrade with help from a spooky source: spiders spinning super-fine silk.
Humans hear through their eardrums, which sense pressure changes and tell the brain where a sound is coming from. But spiders actually use their hairs to detect the velocity of air to decipher sounds.
Engineers at Binghamton University harnessed those sound-sensing capabilities by taking spider silk, coating it in gold so it could conduct electricity, and incorporating it into a microphone, like those found in hearing aids. New research on the approach was published Monday in the journal Proceedings of the National Academy of Sciences.
“The microphone consists of super-thin fibers that move with the air in a sound field,” said Ron Miles, a mechanical engineer at Binghamton University who created the microphone. “The fibers are driven by viscous forces in air, like those that cause tiny dust particles to float around in a slight breeze.”
Hearing aids work by taking pressure changes created by a noise, turning them into an electric audio signal, and translating that into a sound. The spider-inspired microphone operates in a different way: It takes movements in the air, rather than pressure changes, and converts them into audio signals that relay sound.
Another potential benefit of the new approach: It better processes low-frequency sounds that standard hearing aids aren’t good at picking up on, according to Miles.
“It sounds great,” he said.