Bio-Inspired Spider Silk Microphones May Be on the Horizon

We all know how awesome spider silk is. It’s super strong, lightweight and super flexible. That’s why researchers have for decades sought to utilize spider silk goodness in their inventions. Creating spider silk in large enough quantities has been problematic, however, largely due to the lack of gargantuan spiders willing to be milked.

One pair of researchers has found a potential use for spider silk in small quantities, however.

Professor Ron Miles and graduate student Jian Zhou of Binghamton University, State University of New York recently published a paper in the Proceedings of the National Academy of Sciences of the United States of America titled "Sensing fluctuating airflow with spider silk," which highlights how this wondrous material can be used in sound devices.

Spider silk—good stuff (Image courtesy of Sharp Photography/Wikimedia Commons.)

Many types of insect rely on using tiny hairs inside their little insect heads to detect changes in airflow velocity. Due to the excellent aerodynamic and resonant properties of spider silk, these hair-based flow sensors in terrestrial arthropods are actually some of the most sensitive biological sensors on Earth—they even surpass photoreceptors, which can detect a single photon.

The research has shown that spider silk can move with a velocity close to that of the surrounding air, and at frequencies near their mechanical resonance, despite the low viscosity and low density of air. This means that in principle, if devices were made using spider silk, they would be the most efficient human-made sound transducers ever created.

The next stage, according to the paper, is to somehow turn the spider silk into an electrical conductor. Then, by process of electromagnetic induction, the researchers hope that the vibrating thread can be turned into an electrical signal. This would in principle create a miniature, directional, broadband, passive sensor that is capable of detecting sounds over a frequency bandwidth that spans the full range of human hearing, as well as that of many other mammals.

This could potentially have a wide range of applications, including hearing aids, microphones, earphones and a lot more. Of course, the applications are not just confined to consumer-grade electronics but could be used in a range of fields where sensitive measurements of fluid flows are required.

Unfortunately, the researchers make no mention of how they would harvest the spider silk if they plan to mass produce it for commercial use.  My own imagination has conjured up some creepy-looking imagery, though, with battery farms full of captive spiders being milked of their prized resource.

Here is a video of spider milking on a small scale, just in case you were wondering.