INNOVATIVE techniques to miniaturise acoustic systems are being developed in research led by the University of Strathclyde.
There are significant emerging possibilities in the control and manipulation of sound with the advent of new technologies such as 3D printing, and new science in the form of acoustic metamaterials. However, due to long wavelengths of sound associated with speech and audible noise, miniaturising the systems to make them wearable as personal audio and medical devices like hearing aids can be challenging and expensive.
The RESINators – Miniature Acoustic Resonator Systems – project has been awarded just under half a million pounds to achieve acoustic functionality from simple, easy to make systems rather than relying on electronic solutions.
It will investigate how sound works with acoustic resonators formed of metamaterials, a class of material in which its acoustic properties come from the way that it is built, not from what it is built.
The materials can be constructed in such a way as to create effective material properties which are impossible in traditional materials and can be used to cloak objects from sound, to show extremely efficient noise suppression.
Project lead, Dr Joe Jackson from the University of Strathclyde’s department of Electronic and Electrical Engineering, said that with advances in manufacturing methods, it is now possible to build complex geometrical objects using 3D-printing methods with features in the microscale.
He added: “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.”
“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.”
“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.”
“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.”
The project is a collaboration with the University of Glasgow. Dr Andrew Feeney, who is providing advanced materials expertise, said: “Advances in our materials science and fabrication capabilities are presenting new opportunities for acoustic devices. We are now able to fabricate at smaller scales than ever before, but importantly we can also detect the motion of these resonators with our advanced characterisation facilities, which include non-contact instruments such as lasers.
“I am excited to be part of this project, where our long experience in the development and characterisation of advanced materials and devices combines well with Dr Jackson’s research.”
The three-year project is funded by the Engineering & Physical Sciences Research Council, part of UK Research & Innovation.