A team of researchers has created a way to inexpensively manufacture acoustic head simulators. They can help measure the way we take in and process sound – especially in noisy environments like cocktail parties.
When it comes to making better acoustic devices like hearing aids, acoustic signal processing researchers need tools that can help them get a better grip on how our heads and ears take in and process sound.
While there are devices that can help, known as acoustic head simulators, they tend to be expensive so it's rare that a lab would have more than one. That's useful in gathering some data, but it doesn't help the scientists understand how sound is processed in environments where lots of individuals are speaking at once, such as at a party or sports event. Experiments with human subjects in noisy rooms have been conducted, but this avenue of research comes with its own issues.
"Simulating realistic scenarios for conversation enhancement often requires hours of recording with human subjects," said Austin Lu, a student member of a research team from the Augmented Listening Laboratory at the University of Illinois Urbana-Champaign. "The entire process can be exhausting for the subjects, and it is extremely hard for a subject to remain perfectly still in between and during recordings, which affects the measured acoustic pressures.”
To solve both issues, the team figured out how to create a series of acoustic head simulators through 3D printing. They then placed these heads on swivels to mimic the human neck. The heads all have speakers in their mouths to mimic speech, and highly detailed ears fitted with microphones.
By getting the heads "talking," "listening," swiveling, and nodding, and by running the results through a series of algorithms, the researchers are hopeful that they'll be able to gather a large amount of acoustic data quickly and inexpensively. That data should lead to better algorithms which, in turn, will lead to better acoustic devices.
The research will be presented at the 184th Meeting of the Acoustical Society of America, currently being held in Chicago, Illinois.
Sources: Acoustical Society of America via EurekAlert, University of Illinois
