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dlloyd80
07-08-1996, 03:21 PM
Dear All,

I posted a requested on BIOMCH-L a couple of weeks ago re availability of
3D and 6D goniometers. Thanks to all those who responded. After reading the
responses and and looking at our requirements again I have decided that it
is probably best for us to construct our own gonimeters. Thanks again to
all those who responded.

Cheers

David Lloyd

ORIGINAL MESSAGE ---------------------------------------------------------
I am currently developing a line of research that looks at 3D or 6D
movement of the knee while it is being be perturbed. The experimental
protocol permits goniometers to be used. I have used the Penny Giles 2D
goniometers but I am wanting to measure greater degrees of freedom. I am
also unsure as to the ability of these to measure rapid perturbations, ie.
up to 30Hz.

So I am wanting to find out about the availability of 3D or 6D goniometers
and the users' experience with these instruments. Thanks in advance for
your responses and I will post a summary as usual.
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RESPONSES --------------------------------------------------------------
From: c.kirtley@info.curtin.edu.au (Chris Kirtley)
David,

You might like to get in touch with Tim Barker in Brisbane
. He did his PhD on developing the 3D gonio for P&G
with the original inventor, Sandy Nichol, at Strathclyde. I do know that
Tim was unable to come up with a direct relationship between gauge outputs
and angles and had to use a gigantic look-up table!

Chris

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From: zhangl@casbah.acns.nwu.edu
Hello David,

The 6 DOF goniometer I have is from Dr. Richard Shiavi at Vanderbilt
University. A mechanical Engineering professor designed it and I modified
it a little bit and duplicated one. It is not commercially available now
and there is no complete mechanical drawings. I have some drawings but they
are neither complete nor in order. When I made mine, we did not find the
drawings very helpful and used the actual goniometer as a model.
I have been trying to reach Dr. Shiavi and see whether he would like
to have one duplicated for you. I will let you know as soon as I got
an answer from him.

Li-Qun Zhang
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From: jharlaar@cca.vu.nl (Jaap Harlaar)
Hi David,

you should read CHAO, EY, J. Biomech. 13:989-1006 (1980). He's done
wunderfull things in 3D goniometry. I do not think anaything is on the
market so you'll have to make it yourself. But beware: measuring 30 Hz with
an exoskeleton, requires a VERY stiff construction and a VERY firm fixation
(direct to the bone) My guess would be it's just impossible.

Regards, Jaap Harlaar
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From: "CHRISTIAN HAID"
Achim Wilke (Universitaetsklinikum 89070 Ulm, Germany, Helmholtzstr. 14)
designed a 6D Potentiometer for measuring movements in the spine. hope
this helps

Chris
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From: "Neil Glossop"

I wourked on a 6D Groaniometer for a large part of my consious life. It was
not pleasant (difficulty with axis systmes) but you can contact the new
custodians at Baylor Medical Centre in Dallas, Texas: 214-820-3434. Ask to
speak with the person responsible for the goniometer.

Good luck (you'll need it :-) )

Neil

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From: Graeme Jones
David,

I am note sure of the frequency response of the Penny Giles goniometers,
but I do know that the magnetic tracking system "Flock of Birds" will allow
you to look at positions and rotations (relative to a transmitter frame of
ref).

I am also interested in your procedures. I am currently looking at body
perturbations (particularly in the knee) after steping on a patch of ice,
and the consequent postural responses. So I am interested in any knowledge
of the response characteristics of static and dynamic systems to a given
perturbation.

Thanks

Graeme Jones
University of Minnesota
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From: Scott Myers

I've worked with the Penny & Giles goniometers and found them to be
expensive and vulnerable to damage. Remember Wheatstone bridges, theirs are
unbalanced. It's very difficult to resolve unknown resistance from an
unbalanced wheatstone bridge. Excitation voltage is permitted only within
very strict limits or again, the device is destroyed. Put a crimp in the
sensor cable accidently and the device no longer works.

I'm using accelerometers (new low noise, low G monolythic) as
inclinometers. 3D inclinations are possible w/3 arranged as XYZ in a small
cube (1"^3). They can be used as accelerometers at the same time if that
data is relevant.

Sample and downloadable runtime software are available at
http://www.desktoplabs.com/ Goniometer is also shown as example virtual
instrument, which mates with Science ToolBox, a portable signal conditioner
for LabVIEW software and LabCards (included).

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From: R.J.ABBOUD@dundee.ac.uk

I have been using the Isotrack 3D goniometry system for over two years now.
It is accurate to within one degree which is very crucial in my
application, ankle/subtalar joint motion.

The system is available from :
Polhemus Incorporated
A Kaiser Aerospace & Electronics Company P.O. Box 560, 1 Hercules Drive
Colchester, Vermont 05446
USA
tel: (802) 6553159
fax:(802) 6551439
contact name :Mr Tom Jones (he knows me) system name is: Isotrack 3D

Good luck.

Yours sincerely,
Dr Rami J Abboud
Lecturer in Orthopaedics & Trauma Surgery Foot Project CoordinatorTo:
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From: skvorts

Dear David G. Lloyd:

The triaxial didgital goniometers are manufacturing by the MBN company in
Moscow Russia. The typical frequency of sampled data is 100 Hz. But, it is
available higer frequency. You will be able to get more information to send
a requirest by the fax in Moscow:
(095) 238-3773

Yours,
Dmitri Skvortsov