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Hello Mr. Imran Sharif,
Thank you for your interest in the Ariel Dynamics technology.  We manufacture two lines of biomechanical research equipment: the Ariel Performance Analysis System (APAS) and the Ariel Computerized Exercise Systems (ACES).
The APAS is a 3D video-based movement analysis system which accurately quantifies function and provides objective data the professional may use to justify or evaluate treatment.  Areas of successful application for the APAS include human performance, injury and rehabilitation assessment, quantification of loss for compensation claims, equipment and product testing and development, determination of potential or actual risks for products and activities in liability litigation, as well as applied
research in the areas of orthopedic medicine, therapeutics, and physical training.

The APAS integrates state-of-the-art computer and video processing hardware with specialized software modules that perform data collection, analysis, and presentation.  Objective quantifiable documentation is provided for both 2-Dimensional and 3-Dimensional analysis.  Specific points of interest can be digitized with user intervention or automatically using contrasting markers.  Stick figures are then generated and can be synchronized with kinematics data.  Additionally, up to 32 channels of analog data (i.e. force platform, EMG, goniometers etc.) can be synchronized with the kinematics data.

The APAS product information can be found on the Ariel internet site (/).  The direct address to several areas that might be of interest are listed below.

 APAS Product Information

 Comparison of Commercially Available Systems

 Selected Applications Of APAS

 Selected Publications Utilizing the Ariel Technology

ARIEL 3D-Renderer Module
APAS-GAIT Analysis Modue

You can even download a full version of the APAS for a free 30 day trial.

The ARIEL CES is a computerized exercise/rehabilitation system that is capable of isokinetic, isometric, isotonic and user-defined exercise protocols.  Additional information can be found on the Ariel internet site.  The direct address for the CES information is listed below.
Please review the information and feel free to contact us for any additional questions.


John Probe
Ariel Dynamics, Inc.

----- Original Message -----
From: imran sharif
Sent: Saturday, March 17, 2001 4:16 PM

Dear Sir/Madam,
I am currenly writting a reseach paper on the gait analysis systems available on the market and will be greatful if you could send literature/ information/ researh material of the the two types of systems offered by you.(APAS,ACES) 
Kind regards,
Mr Imran Sharif
Consutant orthopaedic surgeon.
Fax no. 00-353-46-74936

General Information

Hi Gideon -
OK. This is the current status. I really don't think there are too many difficulties:
1. All software works great when EVERYTHING is installed with DEFAULT settings. This is what is recommended on our web site.
2. The latest versions of JRE and J3D on our web site can be installed anywhere. These installers are very smart, and anything you choose will work. Try it and you'll see.
3. If the customer must absolutely install APAS in a different place, simply make sure that APAS and APAS/Renderer and APAS/Gait will end up "together". In the default case it is:
C:\Program Files\Ariel Dynamics\APAS\
C:\Program Files\Ariel Dynamics\APAS 3D Renderer\
C:\Program Files\Ariel Dynamics\APAS Gait\
But for example the following will also work:
C:\Test\APAS 3D Renderer\
C:\Test\APAS Gait\
Otherwise my software won't find the CrypKey "license".
Any suggestions to improve this installation are welcome. I am CC-ing this to Jeremy and John also. I only consider 3 (the licensing issue) to be a "problem", but this problem does not occur if the user uses the default installation directory.
- Rudolf
-----Original Message-----
From: Gideon Ariel []
Sent: Thursday, March 15, 2001 04:29
To: Rudolf J.C. Buijs
Subject: Fw: APAS Site Key#1

Hi Rudolf:
  YOu see the problems I have everyday....Many interested. I am sure we will overcome these difficulties.
----- Original Message -----
From: Gideon Ariel
Sent: Wednesday, March 14, 2001 9:22 PM
Subject: Re: APAS Site Key#1

Hi Rick,
Based on the information you listed below, you would probably require the following
   D:\APAS (leave this one as is)
   D:\ARIEL 3D Renderer
Also, make certain that you follow the installation instructions for the JAVA programs EXACTLY AS LISTED.  Both JAVA programs must be installed to the same JAVA directory.  By default, they install to different directories.
Please let me know your results.

Dear Dr. Sumer -
Dr. Ariel has asked me to respond to your e-mail. I have been working with Dr. Ariel for many years on a wide variety of subjects, including gait analysis.
All APAS/Gait information is available on-line. Please check the entry page at:
Our philosophy is that printing brochures will only increase the cost of the system without any additional benefits, so please check the above site. We try to keep the price of the system as low as possible for our customers. All information pertaining to our gait product is available there, including prices, manuals, tutorials, etc.
We are always interested in finding new partners in marketing our APAS and APAS/Gait software. Please contact Gideon if you are interested in becoming a partner. It may be a very nice business opportunity.
Regards - Rudolf
Rudolf J.C. Buijs
Ariel Dynamics Inc.
----- Original Message -----
Sent: Wednesday, March 07, 2001 4:33 AM
Subject: Dr. Aykut Sumer

Dear Dr. Ariel,
You may remember me as I had sent you my resume last year in order to seek a position in your company. That time I had no work permit but afterwards I obtained an H1B work permit while working for a company in Florida. Unfortunately I had some disagreement with this company so I returned back to Turkey. I am still teaching Biomechanics courses in Biomedical engineering institute of Bogazici university in Istanbul, Turkey. (
There will be a Gait Analysis seminar soon. I will be meeting all the doctors who are interested in this subject in Turkey. I would like to have your brochures before I attend to the seminar since I will meet a group there to talk about installing a gait Lab in a University hospital. So I would appreciate if you could please mail me several copies of original brochures.
Best Regards,
Dr. Aykut Sumer
Ph.D. in BioMechanics
Bogazici University
BiyoMedikal Muh. Enst.
Mob.Tel. +90-532-6153421
Mob.Fax. +90-533-9811310

Dear Dr. Seong Jae Lee -

Dr. Ariel has asked me to respond to your e-mail. I am forwarding the answer
that I received from Dr. Sun Chung, one of the world's leading gait experts
who is working with us.

I hope this information is helpful to you. You can contact Dr. Chung, Dr.
Ariel, or myself if you need any further information.

Regards - ir. Rudolf J.C. Buijs, Ariel Dynamics

---- From Dr. Sun Chung -------------------
I am very glad to communicate with you. I am Sun Chung in Seoul. May I
answer your question to Gideon?

> > In the HHm/Anthro item 23/24
> > the Right anterior - posterior ASIS/HJC component (m), what this means?

This anthropometric data can be measured manually. We take a point on the
superior part of greater trochanter(GTroch) by palpation. And draw a
vertical line from the point, "vertical" assuming that the subject are
standing. We measure the shortest distance between this line to the
ipsilateral ASIS. You may have some problem to locate the GTroch point
because it is somewhat blunt. Which point should we choose in this rather
blunt bony landmark? To solve this problem, we may look over the original
article of Roy Davis (Davis RB et al. A gait analysis data collection and
reduction technique. Human movement science 1991(10): 575-587). They took
this GTroch point for the hip joint center in sagittal plane. Dr. Perry
wrote on her book "Gait analysis" that the hip joint center overlies at the
anterior superior margin of the GTroch(Page 368, figure-17.7). So, I usually
recommend to take the anterior point of GTroch. What do you think?

Actually, I do not like this approach (Roy Davis's approach) to estimate hip
joint center.
   1. The measurement(GTroch to ASIS) is too error prone.
   2. The hip joint center in sagittal plane will be influenced by the
amount of femoral anteversion, which varies individually.
   3. As you can see on the article, their data were based on only the
children's pelves.
   4. They did not report any detailed method to take the x ray and
measurement for their estimation.

I had tried to reproduce their result with Korean adult pelves. But failed
to. I prefer Bell's approach but it is not the best. I hope we can have the
way to estimate the hip joint center in the near future. Would you like to
read this page

Only if you may be ready to read broken English.;-)

----- Original Message -----
From: "Seong Jae Lee" <>
To: "Gideon Ariel" <>
Sent: Tuesday, March 06, 2001 7:15 PM
Subject: Question about the anthropometry in APASGAIT

> Dear Dr. Ariel,
> I downloaded APASGAIT and have been trying it.
> It is working well and easy to use.
> But among many items in anthropometric data, I just don't understand
> what "anterior-posterior ASIS/HJC component" means and how to
> measure or calculate it. I'm supposed to use Helen Heyes modified
> marker set.
> Please let me know how to measure or calculate it.
> Sincerely,
> Seong Jae Lee, M.D.
> Department of Rehabilitation Medicine
> Dankook University Hospital
> San 16-5, Anseodong, Cheonan
> Choongnam 330-715
> Korea
> Phone: +82-41-550-3898
> Fax: +82-41-551-7062
> E-mail:





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