View Full Version : Light gates - replies

Kevin Semeniuk
09-03-1997, 03:41 AM
On July 4, 1997, I posted an inquiry regarding the purchase of
light gates (photo cells). The following is a list of the replies. Sorry
for the lateness of this return (the lakes stay warm for only a few
months), and thanks again to all those who replied. Very much


Lafayette Instruments makes an infrared photo cell. They did make an
incandencent light photo cell, like the ones I use, but I couldn't find
them in the catalog I have. The price list I have, which is a couple of
years old, has them for $280 (US). Their contact information is below.

Lafayette Instruments
P.O. Box 5729
3700 Sagamore Parkway North
Lafayette, Indiana 47903
(800)428-7545 Phone
(317)423-4111 FAX

A graduate student I advise is studying gait speed in patients with low
back pain. In addition to average velocity, he wants to know the
durations of steps and strides. He is using an instrument called
GENLOCK which puts a small digital clock in the corner of the
camcorders view and runs displays the time in hundredths of seconds.
The clock is recorded on the videotape. He then plays the tape on a
slow motion VCR and records the times. I don't have the information on
the manufacturer of the GENLOCK, but if you think you would like more
information on it, let me know and I will look it up.

Good luck!

Bruce Etnyre, Ph.D., P.T. _/_/_/_/ _/_/_/_/ _/_/_/ _/_/_/_/
Human Performance and _/ _/ _/ _/ _/ _/ _/
Health Sciences Dept. _/ _/ _/ _/ _/ _/
Rice University _/_/_/_/_/ _/ _/ _/_/_/ _/
6100 Main MS 545 _/ _/ _/ _/ _/ _/
Houston, Texas 77005 _/ _/ _/ _/ _/ _/
USA _/ _/ _/ _/ _/ _/ _/
etnyre@rice.edu _/ _/ _/_/_/_/ _/_/_/ _/_/_/_/ _/_/
FAX: (713)285-5329



I am not sure if this company carries what you need but they may be able to
point you in the right direction:

1207 Maple St.
P.O. Box 65310
West Des Moines, IA, 50265
(800) 280 6933
(515) 225 6933
Fax: (515) 225 0063

They carry Photo electric sensors that are used for a variety of purposes.
Good Luck!
% Juan C. Garbalosa, Ph. D., PT
% Assistant Professor
% University of Hartford
% Department of Physical Therapy
%200 Bloomfield Ave
% West Hartford, CT 06117

% Phone (Work): (203) 768 5371
%Fax (Work):
% email: Garbalosa@uhavax.hartford.edu


Hey Kevin:

We use light gates from a company in Plano, Texas:


Good luck.

Tyler A. Kress, Ph.D.
The University of Tennessee
153 Alumni Memorial Building
Knoxville, TN 37996-1506
Phone: (423) 974-3333
Fax: (423) 974-0588


Hi Kevin,
I had the similar experience when trying to acquire one for our lab.
Here is what I did. I purchased photocells from Cutler-Hammer
(1-800-833-3927) and a digital clock from Kessler Ellis Products
(1-800-631-2165) and wired it up myself. I cost about $500.00 total and works
great. I think Lafayette Instruments makes a total package (sensors and
timers) but I think that it is more expensive (about $1,000).

If you need more specifics, please e-mail me directly.

Tom Kernozek, Ph.D.
University of Wisconsin - LaCrosse
Physical Therapy Department


We do a large amount of custom instrumentation for Indiana University
Human Performance Laboratories and many others. If you are unable to
locate devices that will work for you we may be able to design some
relatively inexpensive ones for you. Please feel free to contact us at
any time at locations below.

Dwight H. Hector, Ph. D.
__________________________________________________ ________________

HECTOR ENGINEERING CO., INC. Phone 812-876-5224
123 E. Dewey, P.O. Box 566 FAX 812-876-5223
Ellettsville, IN 47429 E-mail dhector@worldnet.att.net
__________________________________________________ ________________



There are several companies that make light curtains. Is that what you're
looking for? Or are you looking for basic timing lights? If you could tell
me more about what you're trying to do I'll be glad to point you to
companies that I'm aware of. Also what kind of response time and accuracy
do you need? I am writing a paper on timing light accuracy and have learned
a lot about overall accuracy. Are you looking for a "turn-key" system or
components to integrate into an existing system?

Tom Westenburg
US Olympic Committee


Dear Kevin,
Your Email below has been referred to us.

Please refer our home page http://www.chariot.net.au/fittech
In our products section you will find our Kinematic Measurement System,
please read same.
You can download an instruction manual from this product section
together with a full operating demonstration software system that will
perform exactly the functions you require plus a whole lot more.
In brief the left shift key on your PC is used as a simulation switch in
your instance simulating as many number of timing gates that you
require. Remember from the pull down menu you must 'insert' a subject
name & body weight prior to any test.

Any queries please Email me.

Ian Crossing

Fw: light gates...
Mon, 7 Jul 1997 16:17:58 +1000
"Robert Newton"
"Fitness Technology"

> -------------------------------------------------------------------

Hi Kevin

I don't have addresses and being in the UK that may not be a problem.
We have found that light gates developed for security systems are
cheap and effective. Commercial ones we were using earlier seemed to
require a minimum amount of time for interruption of the signal.
While this would not be a problem for studies of locomotion, our need
was for something to indicate the onset of fast movements, i.e.
ball's or clubs.

Typically, the security ones are TTL compatible and very simple to

Hope this helps

Frank Eves

School of Sport and Exercise Sciences
University of Birmingham
Birmingham B15 2TT

Tel: +44 (0)121 414 4133
Fax: +44 (0)121 414 4121
E-mail: evesff@sportex.bham.ac.uk