Featured Research

from universities, journals, and other organizations

Measurement scientists set a new standard in 3-D ears

Date:
October 17, 2010
Source:
National Physical Laboratory
Summary:
Scientists have developed a means of representing a 3-D model ear, to help redefine the standard for a pinna simulator (the pinna is the outer part of the ear) -- used to measure sound in the way we perceive it.

This is an image of the NPL artificial ear.
Credit: NPL

Scientists at the UK's National Physical Laboratory (NPL) have developed a means of representing a 3D model ear, to help redefine the standard for a pinna simulator (the pinna is the outer part of the ear) -- used to measure sound in the way we perceive it.

Related Articles


The nature of human hearing is heavily dependent on the shape of the head and torso, and their interaction with sound reaching the ears allows for the perception of location within a 3D sound field.

Head and Torso Simulators (HATS) are designed to model this behaviour, enabling measurements and recordings to be made taking account of the Head Related Transfer Function (HRTF) -- the difference between a sound in free air and the sound as it arrives at the eardrum.

HATS are mannequins with built-in calibrated ear simulators (and sometimes mouth simulators), that provide realistic reproduction of the acoustic properties of an average adult human head and torso. They are ideal for performing in-situ electro-acoustic tests on, telephone handsets (including mobile and cordless), headsets, audio conference devices, microphones, headphones, hearing aids and hearing protectors.

Critically the shape of the pinna has a large effect on the behaviour, and as a result it is defined for HATS by its own standard (IEC TR 60959:1990) to provide consistency across measurements. However, this standard defines the shape of the pinna through a series of 2D cross-sectional profiles. This form of specification and definition has on occasion proven to be an inadequate guide for manufacturing processes.

As part of a revision of this standard, the Acoustics Team at NPL teamed up with the National Freeform Centre in a novel move to redefine the standard through an on-line 3D CAD specification. A model ear was measured using a coordinate-measuring machine with laser scanner to produce a 3D scan of the ear, which can then be used to provide manufacturers with a more practical specification for reproduction and a standard that is easily comparable with similar non-contact freeform measurement techniques.

Ian Butterworth from NPL, said: "Having a 2D pinna in an artificial ear has some inherent frequency limitations. For example, when sound spreads through structures like narrow tubes, annular slits or over sharp corners, noticeable thermal and viscous effects take place causing further departure from the lumped parameter model. The new standard for the 3D model has been developed to give proper consideration to these effects. We worked with the National Freeform Centre, experts in measuring items that are unconventional in shape or design, to develop the new standard -- which will now help manufacturers develop better products."


Story Source:

The above story is based on materials provided by National Physical Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

National Physical Laboratory. "Measurement scientists set a new standard in 3-D ears." ScienceDaily. ScienceDaily, 17 October 2010. <www.sciencedaily.com/releases/2010/10/101012101251.htm>.
National Physical Laboratory. (2010, October 17). Measurement scientists set a new standard in 3-D ears. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2010/10/101012101251.htm
National Physical Laboratory. "Measurement scientists set a new standard in 3-D ears." ScienceDaily. www.sciencedaily.com/releases/2010/10/101012101251.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Melafind: Spotting Melanoma Without a Biopsy

Melafind: Spotting Melanoma Without a Biopsy

Ivanhoe (Oct. 31, 2014) The MelaFind device is a pain-free way to check suspicious moles for melanoma, without the need for a biopsy. Video provided by Ivanhoe
Powered by NewsLook.com
Battling Multiple Myeloma

Battling Multiple Myeloma

Ivanhoe (Oct. 31, 2014) The answer isn’t always found in new drugs – repurposing an ‘old’ drug that could mean better multiple myeloma treatment, and hope. Video provided by Ivanhoe
Powered by NewsLook.com
Chronic Inflammation and Prostate Cancer

Chronic Inflammation and Prostate Cancer

Ivanhoe (Oct. 31, 2014) New information that is linking chronic inflammation in the prostate and prostate cancer, which may help doctors and patients prevent cancer in the future. Video provided by Ivanhoe
Powered by NewsLook.com
Sickle Cell: Stopping Kids’ Silent Strokes

Sickle Cell: Stopping Kids’ Silent Strokes

Ivanhoe (Oct. 31, 2014) Blood transfusions are proving crucial to young sickle cell patients by helping prevent strokes, even when there is no outward sign of brain injury. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins