Radical hearing aid design draws on an unlikely inspiration
While the majority of us would be very happy to see out the summer without flies ruining our outdoor dining experience, one particular species of fly has provided the inspiration for a potential breakthrough in the technology of hearing aids. It's not just any old house-fly we're talking about, though.
Binghamton University engineering professor Ron Miles says this particular fly, called the ormia ochracea, is special because it’s as good as a human at locating the source of a sound.
“The female fly, when she’s pregnant and needs to have her babies, she listens for crickets to sing," says Miles. "And when she hears the cricket, she’ll fly to the cricket and have her babies and these maggots then burrow into the cricket and a few days later, they’ll emerge and leave a hollow shell.”
So the fly’s behavior isn’t pretty. The way most animals locate sound doesn’t work for ormia ochracea, and it's useful to know how this tiny parasite can locate its host.
“So you can tell where sound comes from usually because, if it comes, say, from the right side, your right ear is going to hear the sound before your left ear,” says Miles.
The bigger a creature's head, the more information it has to work with. But this fly’s ears, located where it's chest would be, are so close together that sound arrives to both ears at the same time.
Miles, working with biologists more than a decade ago, found that ormia ochracea’s ears are connected by a previously unknown mechanism.
“If you push down on one ear drum really carefully so you don’t break it, the other ear drum will pop up and they actually rock about a central hinge, kind of like a teeter-totter,” says Miles.
The difference in vibrations between the two sides is how the fly figures out which side the sound is coming from.
Miles took that design and made it the basis for a 3mm microphone, about the size of 3 grains of sugar. It’s different from any other directional microphone on the market.
“The end result is that if you’re in a noisy place with sound coming from all around, our microphone will help get rid of the background noise,” says Miles.
But this invention isn’t new. Miles began developing the technology ten years ago with grants from the National Institutes of Health and the National Science Foundation.
Now, Miles says that money has dried up and the biggest obstacle is still ahead of him.
How to commercialize?
“We’ve, you know, succeeded in showing that the research is right but the next challenge then is turning it into something that you can buy,” says Miles.
That’s where SUNY’s Technology Accelerator Fund comes in, which gave Miles a $50,000 grant in 2011.
The purpose was to commercialize his hearing aid. But the manufacturing process is new and expensive and that makes it hard to find a company to license it to.
Miles says that his struggles to turn it into a profit-maker are not uncommon for inventors.
“There are lots of things, lots of patents in this world that don’t really generate much money,” he says.
Eugene Kruntsel is in charge of innovation partnerships at Binghamton University. He says inventions like this one are still important, whether or not they can be made profitable.
“Well, the most important thing about technology commercialization in academia is impact, it’s not the income, it’s the impact on the society to the betterment of the world, so to speak,” says Kruntsel.
Both Kruntsel and Miles are hoping that extra prototypes, built with money from NY state, will convince a company that new and improved hearing aids are worth the investment.