A Fly With Unique 'Ears' Becomes Inspiration For New Hearing Aid
Biomimicry has again inspired a creative team of scientists. This time it's the Ormia ochracea, a tiny fly with exquisitely acute directional hearing ability, that has become the model for the next generation of hearing aids being modeled by engineers at the Cockrell School of Engineering at the University of Texas at Austin.
The fly has a unique hearing mechanism; its two tympanic membranes, what we know as 'eardrums,' are mechanically connected, which allows almost pinpoint directional hearing within nanoseconds. This ability aids the Ormia ochracea in quickly locating its favorite prey, the cricket.
The model above depicts the prototype of the potential hearing aid developed at the Cockrell School. Piezoelectric materials are inserted in the device that measure the rotation and flexibility of the beam, the teeter-totter in the diagram. This design allows the developers to replicate the hearing of the O. ochracia. The silicone beam, 2 millimeters wide, is even the same size as the fly's hearing mechanism.
The aims of the Cockrell engineers are to create a hearing aid that is desirable to wear and that uses little energy. Traditional hearing aid microphones amplify all sounds and are unable to focus, the way the O. ochracia can, on the user's point of interest. Therefore, the researchers say, only two percent of the populace use hearing aids, whereas 10 percent actually need to wear hearing aids.
Additionally, the newly proposed hearing aid will obviate the need to continually change hearing aid batteries, as piezoelectric power conserves a lot of energy.