Insect ear inspires hearing aids

A microphone that can locate sounds and eliminate background noise has been inspired by the ear of an insect.

Research by the University of Strathclyde, and the Medical Research Council /Chief Scientist Office (MRC/CSO) Institute for Hearing Research (IHR) - Scottish Section at the Glasgow Royal Infirmary, will test a design using a miniature directional microphone.

Current directional microphone technology adds cost, weight and power requirements to hearing aids compromising their design. The collaborative research aims to create a hearing aid system that can reduce or control unwanted noises, focusing the hearing aid on only the sound arriving from in front of the user.

Dr James Windmilll, of the Centre for Ultrasonic Engineering at Strathclyde, said: "Currently, users can tell whether a sound source is in front or behind, but struggle to detect sounds from below or above, such as echoes in a large room.

"We aim to solve the problem using a new type of miniature directional microphone, inspired by how some insects hear sounds.

"We will be able to evaluate the problems caused by the distance from which a sound emanates, for example how to separate a sound from a loud source far away, like a train or plane, from a quiet sound from nearby, like a human voice.

The project will also investigate 3D printing techniques to optimise hearing aid design to work in conjunction with the new microphone."

Strathclyde will design, build and test the new microphones and hearing aid structures. IHR will test the operation as hearing aids, including human trials of the new designs.

The research is being funded by the Engineering and Physical Sciences Research Council with a £430,000 grant.

In the UK, 8-10 million people are affected by hearing loss, including 50% of those aged 75 year and over. Only 20% use hearing aids, with poor sound quality and poor performance in noisy and complex environments, cited as reasons for the low take-up.