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Hinrichs, Rick
02-12-1993, 10:36 AM
Dear Biomch-l subscribers:

A couple of months ago I posted a request for info on 3-D electrogoniometers.
I received several messages immediately and several more have been trickling
in since that time. I summarize them below. Sorry for the delay in posting
this summary to the list.

--Rick

Richard N. Hinrichs, Ph.D.
Dept. of Exercise Science
Arizona State University
Tempe, AZ 85287-0404 USA
(602) 965-1624
(602) 965-8108 (FAX)

email: Hinrichs@ESPE1.LA.ASU.EDU

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---------------My original posting------------------

Dear Biomch-l subscribers:

Can anyone give me some information on commercially available triaxial
electrogoniometers (elgons)? I would like to see what is available from a
variety of vendors and the approximate cost of each. Are there any devices
that can measure translations as well as rotations (six degrees of
freedom)? Are there others that measure just the rotations? I would
appreciate hearing from anyone who has used these devices as to how well they
work to measure human joint motion. I am particularly interested in
quantifying head/neck motion and shoulder motion in a clinical setting.
Thanks in advance.

--Rick

Richard N. Hinrichs, Ph.D.
Dept. of Exercise Science
Arizona State University

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From: "D. M. Pickles"

I have experience of a biaxial goniometermanufactured by Penny
and Giles Biometrics (Tel +44 495 228000; Fax +44 495 229389).
I think they may do a triaxial one as well but am not sure. Give
me a shout if you want any further information.

--Regards

David Pickles
Comparative Orthopaedic Research Unit
Department of Anatomy
University of Bristol
Park Row
Bristol
BS1 5LS
United Kingdom

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From: Chris.Grant@um.cc.umich.edu

At the Center for Ergonomics at the University of Michigan we
have been working with triaxial goniometers; I believe they
are the Penny & Giles ones. We found significant crosstalk
between the channels when using them on the forearm and back
of the hand. The crosstalk happened when, of course, the
forearm went from supination to pronation and back.

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From: James R Harvey

Rick:

There is a company in Florida called Faro Medical that makes a 6 axis
digitizer arm.

I am contemplating starting a company to do the same and would be VERY
INTERESTED in knowing what you need. I have access to some sensors that
would make it quite inexpensive and accurate.

Please get back to me as I am no longer on the BIOMCH list.

Regards,
James Harvey
Timberline Medical
3114 Robinwood Drive
Salt Lake City, UT 84118

(801) 968-2343

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From: Graham_E_CALDWELL@umail.umd.edu

Rick,

I've used several different Elgon systems, and suggest you look at two in
particular. The first is described in Hannah et al., Arch Phys Med Rehab,
65: 155-158 and 159-162, 1984...it is a parallelogram-type elgon system
(they used it for gait analysis, but one of the modules should serve you
well). They were developed at Shaughnessy Hospital in Vancouver, BC. You
might also try contacting Jim Morrison at Simon Fraser, as he had one of
these elgon systems.

The second elgon I would examine is the Penny & Giles model, which
is extremely lightweight, consisting of a flexible calibrated 'bar'. It was
designed by the people at Strathclyde, and has been described by A. Nicol in
several places. Phone MEDmetric Corp in San Diego at 619-536-9122.

Good luck.....Graham Caldwell, Maryland

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From: pieper@northstar.dartmouth.edu (Steve Pieper)

Dr. Hinrichs,

Dr. Delp of Northwestern Univ. forwarded to me your posting to the net
regarding electrogoniometers. (see below). The only system I've
worked on is the dextrous hand master (DHM) made by Exos, Inc. 2A Gill
Street, Woburn, MA 01801, (617) 933 0022 (tel), (617) 933 0303 (fax).
Dr. Beth Marcus is the president (bam@media-lab.media.mit.edu. The DHM
device is the most accurate hand motion measurement system I know of.

Exos also makes a variety of sensor configurations for studying hand
and wrist joint motion, and for studying hand rehabilitation. They
are marketing a new system, called, I think, the Clinical Hand
Measurement System, for quanitfying and recording hand capability
on a Macintosh or PC.

Exos also built a special purpose arm motion system for use in a
musical performance which combined the cellist Yo Yo Ma with a computer
accompanist. That work was done in collaboration with Tod Machover's
group at the MIT Media Lab (tod@media-lab.media.mit.edu).

Good luck in your research. I wonder if you could do me a favor and
send along any other email you collect on joint measurement.
I'm particularly interested in ways to determine what's going on
inside the joint capsule during limb motion.

Thanks,
Steve Pieper, Ph.D.
Assistant Professor of Engineering Science
Thayer School of Engineering
Box 8000
Dartmouth College
Hanover, New Hampshire 03755-8000
(603) 646 2623 (voice)
(603) 646 3805 (fax)
Steve.Pieper@dartmouth.edu (internet)

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From: Mike Whittle

Dear Rick:

The Chattanooga Corporation ("Chattex") make an electrogoniometer
known as "Triax". It looks very similar to the CARS-UBC goniometer from the
mid-1980s. The last I heard, they were redesigning it, and it had been
temporarily withdrawn from sale. I will try and find out more, and let you
know.

In general terms, electrogoniometers mounted on the legs are fine for flexion/
extension angles, but poor for movements in the other planes, unless you
manipulate the data to allow for the off-axis positioning. There is a bit
more on this in my book - Gait Analysis: an introduction. Whittle, M.W.
Butterworth-Heinemann, Oxford, 1991.

The Penny and Giles flexible electrogoniometer (developed at the University of
Strathclyde) seems to be a useful instrument, although I have not used it
myself.

With best wishes,

Mike Whittle
Cline Chair of Rehabilitation Technology
The University of Tennessee at Chattanooga

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From: Mike Whittle

Dear Rick:

I finally managed to speak to the right person at the Chattanooga
Corporation regarding the Triax electrogoniometer. It seems they had such
problems with the device that they decided to withdraw it. There are plans to
introduce another device, probably early in 1994, but this may be a single-
plane goniometer, which avoids the problems inherent in 3-D devices.

With best wishes

Mike Whittle
Cline Chair of Rehabilitation Technology
The Universisty of Tennessee at Chattanooga


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