The wavelengths of sound associated with speech and audible noise are long, meaning that miniaturising the systems needed to incorporate them into personal audio and medical devices like headphones and hearing aids can be difficult. The RESINators project will investigate how sound works with acoustic resonators formed of metamaterials, where the acoustic properties are influenced primarily by the shape of the device, rather than by the material used.
Combining 3D printing with the latest in metamaterials technology, the team believes it will be able to create acoustic properties that would be impossible to achieve using traditional materials, capable of cloaking objects from sound and exhibiting extremely efficient noise suppression.
“It’s challenging to miniaturise things that you can wear on a very small scale that still works at audio frequencies, so we’re seeking to develop new acoustic systems built with microscale features,” said project lead Dr Joe Jackson, from the University of Strathclyde’s Department of Electronic and Electrical Engineering.
“They will operate at audio frequencies pulling together advances in 3D printing and acoustic system design to create materials that have exceptional acoustic performance, while still being lightweight and small scale.”
Much of the R&D around personal audio wearables and medical devices like hearing aids tends to focus on digital signal processing and electronics. According to Jackson, as the complexity of electronics increases, battery life is adversely affected. By taking a closer look at the fundamental structure of acoustic devices, the team believes they can develop next-generation technology that improves the audio experience and could potentially even improve battery life.
“We are aiming to eventually develop cutting edge systems for personal audio that could constitute the science of audio of acoustic systems for the next generation of technologies in wearable consumer products,” said Jackson.
“The majority of research into the sound-detection part of external hearing aids and cochlear implants - an electronic device that electrically stimulates the cochlear nerve for hearing - is related to electronics, such as the analysis of the signals, the digital signal processing. But that is expensive and takes battery life, and the more advanced the devices, the more impractical they can become, with the user having to charge their hearing aid every few hours, for example.”
