Hello Biomch-l subscribers,
About 1 week ago I posted a request for information about using a
new set of kinematic data with the GAITLAB software by Vaughan,
Davis, and O'Connor. My project and problem was stated in a later
response to those who replied to my original message:
Hello Brian , Jeremy and Kit,
Thanks a lot for the reply. I'd much rather talk to the source of
the software than anyone else! Let me begin by describing my
situation:
I am a mechanical engineer working on a project to develop a
functional knee brace for athletes who have strained or ruptured
their ACL. A common complaint about knee braces is that most of the
force/strength testing done for them is either static or not
representative of true athletic motions. Recently I performed some
tests using an ARIEL motion analysis system to look at three motions:
1 - A vertical jump landed on one foot
2 - A cutting motion
3 - A circular running motion(similar to turning the corner on
a track)
My goal was to enter the data into the GAITLAB package and see if it
would give me results. I realized that the package is meant for GAIT
analysis so I did not expect the animation segment to work.
So far the program has accepted my COLIN.KIN file but when I try to
run the "Center of Gravity" procedure using my COLIN.FPL file I get a
"Run Time 200" error. As I see it my problems/differences with the
software are the following:
1 - Because the motions happen quite quickly, I only end up with
about 40 frames worth using 1/60th s (0.0167) intervals
2 - The data does not create a repetitive cycle like one would get
from GAIT analysis
3 - While my global reference frame and marker system are the same as
the ones on page 23, I have only used 1 force plate to catch the
right
heel strike
Do you think that this use of GAITLAB is feasible?
Thanks again,
Colin Paranchych
Department of Mechanical Engineering
University of Alberta
Edmonton, AB
CANADA
(403)492-3742
--------------------------------------------------------------------
Here are the replies which I recieved:
Dear Colin,
In reply to your note :
1. I'm not sure that the "Centre of Gravity" procedure uses the
FPL file, but I'll get back to you on that.
2. 40 frames shouldn't be a problem. The interval being 1/60'th of
a second may be. I did adapt the program for private use by Kit
Vaughan for 1/60'th time intervals but I think the software that was
released to the public was 1/50'th of a second. I'll get back to you
on that one as well.
3. That you only have one force plate is probably going to cause
problems, as I think the program expects 2 force plates in the .FPL
file. One way (the easiest) to overcome this problem is to create a
file with two force plates where the six values (per frame) for the
second force plate remain zero for the 40 frames i.e. a dummy force
plate.
4. As to whether the use of Gaitlab for your problem is feasible
from a mechanics/mathematical point of view you should check with Kit
Vaughan or Brian Davis. I don't see any problem from a software
point of view - as long as the input data files you create have the
correct format and content Gaitlab should handle the job.
Regards,
Jeremy O'Connor
programmer, GaitLab Team.
Colin,
As I outlined in my prevoius message, Kit Vaughan does have a
version of Gaitlab that uses three decimal places and accepts data at
60 Hz. Perhaps he will be able to help you out.
I'm pleased you managed to get the program working with your data.
Regards,
Jeremy O'Connor
programmer, Gaitlab team.
Dear Colin,
Following up on your latest message and Jeremy's reply, there is
a version of GaitLab that will run with 60Hz data. In the *.KIJN
(that should be *.KIN) and *.FPL files, there must be 3 decimaol
places for the time field, i.e. 0.017. You can get the
executable files via anonymous ftp from virginia.edu in the
public_access subdirectory. The file is called gaitlab.exe and
it is a self-extracting ZIP file that creates GAITMATH.EXE and
GAITPLOT.EXE files which will work with 60 Hz data. Let me know
how it goes.
Kit
Greetings:
I have not had the problem you have had because I 1) wrote a program
which generates .kin files with the correct time interval, and 2) the
new software (which I got from c. Vaughan; GAITMATH module is 100,544
bytes) does not seem to have the problem you report. Let me know if
you have the old or new software. I know I had lots of problems with
the old which the new cleared up. All the best.
Cheers ...
Michael Raymond Pierrynowski, Ph.D.
Human Movement Laboratory
School of Occupational Therapy and Physiotherapy
McMaster University, HSC 1J11
Hamilton, Ontario L8N 3Z5
CANADA
1 905 525-9140 x22910 (PHONE)
1 905 522-6095 (FAX)
PIERRYN@FHS.CSU.MCMASTER.CA (INTERNET)
You might have less problem if you write your data with a program in
C. There is somme incompatibilities with FORTRAN format.
I use a FORTRAN program but i had to build the writting routine in C,
so i was force to use a MIXED LANGUAGES program. I belive the format
that the GAITLAB program is able to read is very restrictive.
There is limit in the number of frame and if you tri to read more
data the program crash.
--
DESJPIER@ERE.UMONTREAL.CA
PIERRE DESJARDINS Ing.
Universite de Montreal
Greetings:
I have been using the GAITLAB software with the OPTOTRAK kinematic
data acquisition system. We are currently looking at children with
leukemia. After 25 subjects, with an average of 5 runs each I have
found the GAITLAB software useful. Of course I had to write a bunch
of linking software and I also wrote software to calculate powers,
average across files and plot these results.
I would be welcome to share my experiences with you.
Michael Raymond Pierrynowski, Ph.D.
Human Movement Laboratory
School of Occupational Therapy and Physiotherapy
McMaster University, HSC 1J11
Hamilton, Ontario L8N 3Z5
CANADA
1 905 525-9140 x22910 (PHONE)
1 905 522-6095 (FAX)
PIERRYN@FHS.CSU.MCMASTER.CA (INTERNET)
Colin,
I have a version of the Gaitlab software (Vaughan et al), but
do not use it for any real data. My use is simply for class
demonstrations, etc. (undergrad 'lab' work). There does seem
to be a problem with timing of events, especially with the
stick figures. For example, on page 69 of the accompanying
text the toe-ons and toe offs for the stick figures do not
line up with the LHS and RTO of the EMG diagrams below it.
I have seen other similar timing problems, but am unable
to come up with a specific example at this point. I have
not contacted Human Kinetics about my observations. What
problems have you experienced? Maybe with many inquiries
to Human Kinetics we can get some explanations.
Jeff Ives, PhD
Dept. Exercise Science
Campbell University
Buies Creek, NC 27506
email: jives@camel.campbell.edu
----------------------------------------------------------------------
Thanks again to all the replies, and especially to the authors of
GAITLAB for clearing up my problem.
Colin Paranchych
University of Alberta
Department of Mechanical Engineering
About 1 week ago I posted a request for information about using a
new set of kinematic data with the GAITLAB software by Vaughan,
Davis, and O'Connor. My project and problem was stated in a later
response to those who replied to my original message:
Hello Brian , Jeremy and Kit,
Thanks a lot for the reply. I'd much rather talk to the source of
the software than anyone else! Let me begin by describing my
situation:
I am a mechanical engineer working on a project to develop a
functional knee brace for athletes who have strained or ruptured
their ACL. A common complaint about knee braces is that most of the
force/strength testing done for them is either static or not
representative of true athletic motions. Recently I performed some
tests using an ARIEL motion analysis system to look at three motions:
1 - A vertical jump landed on one foot
2 - A cutting motion
3 - A circular running motion(similar to turning the corner on
a track)
My goal was to enter the data into the GAITLAB package and see if it
would give me results. I realized that the package is meant for GAIT
analysis so I did not expect the animation segment to work.
So far the program has accepted my COLIN.KIN file but when I try to
run the "Center of Gravity" procedure using my COLIN.FPL file I get a
"Run Time 200" error. As I see it my problems/differences with the
software are the following:
1 - Because the motions happen quite quickly, I only end up with
about 40 frames worth using 1/60th s (0.0167) intervals
2 - The data does not create a repetitive cycle like one would get
from GAIT analysis
3 - While my global reference frame and marker system are the same as
the ones on page 23, I have only used 1 force plate to catch the
right
heel strike
Do you think that this use of GAITLAB is feasible?
Thanks again,
Colin Paranchych
Department of Mechanical Engineering
University of Alberta
Edmonton, AB
CANADA
(403)492-3742
--------------------------------------------------------------------
Here are the replies which I recieved:
Dear Colin,
In reply to your note :
1. I'm not sure that the "Centre of Gravity" procedure uses the
FPL file, but I'll get back to you on that.
2. 40 frames shouldn't be a problem. The interval being 1/60'th of
a second may be. I did adapt the program for private use by Kit
Vaughan for 1/60'th time intervals but I think the software that was
released to the public was 1/50'th of a second. I'll get back to you
on that one as well.
3. That you only have one force plate is probably going to cause
problems, as I think the program expects 2 force plates in the .FPL
file. One way (the easiest) to overcome this problem is to create a
file with two force plates where the six values (per frame) for the
second force plate remain zero for the 40 frames i.e. a dummy force
plate.
4. As to whether the use of Gaitlab for your problem is feasible
from a mechanics/mathematical point of view you should check with Kit
Vaughan or Brian Davis. I don't see any problem from a software
point of view - as long as the input data files you create have the
correct format and content Gaitlab should handle the job.
Regards,
Jeremy O'Connor
programmer, GaitLab Team.
Colin,
As I outlined in my prevoius message, Kit Vaughan does have a
version of Gaitlab that uses three decimal places and accepts data at
60 Hz. Perhaps he will be able to help you out.
I'm pleased you managed to get the program working with your data.
Regards,
Jeremy O'Connor
programmer, Gaitlab team.
Dear Colin,
Following up on your latest message and Jeremy's reply, there is
a version of GaitLab that will run with 60Hz data. In the *.KIJN
(that should be *.KIN) and *.FPL files, there must be 3 decimaol
places for the time field, i.e. 0.017. You can get the
executable files via anonymous ftp from virginia.edu in the
public_access subdirectory. The file is called gaitlab.exe and
it is a self-extracting ZIP file that creates GAITMATH.EXE and
GAITPLOT.EXE files which will work with 60 Hz data. Let me know
how it goes.
Kit
Greetings:
I have not had the problem you have had because I 1) wrote a program
which generates .kin files with the correct time interval, and 2) the
new software (which I got from c. Vaughan; GAITMATH module is 100,544
bytes) does not seem to have the problem you report. Let me know if
you have the old or new software. I know I had lots of problems with
the old which the new cleared up. All the best.
Cheers ...
Michael Raymond Pierrynowski, Ph.D.
Human Movement Laboratory
School of Occupational Therapy and Physiotherapy
McMaster University, HSC 1J11
Hamilton, Ontario L8N 3Z5
CANADA
1 905 525-9140 x22910 (PHONE)
1 905 522-6095 (FAX)
PIERRYN@FHS.CSU.MCMASTER.CA (INTERNET)
You might have less problem if you write your data with a program in
C. There is somme incompatibilities with FORTRAN format.
I use a FORTRAN program but i had to build the writting routine in C,
so i was force to use a MIXED LANGUAGES program. I belive the format
that the GAITLAB program is able to read is very restrictive.
There is limit in the number of frame and if you tri to read more
data the program crash.
--
DESJPIER@ERE.UMONTREAL.CA
PIERRE DESJARDINS Ing.
Universite de Montreal
Greetings:
I have been using the GAITLAB software with the OPTOTRAK kinematic
data acquisition system. We are currently looking at children with
leukemia. After 25 subjects, with an average of 5 runs each I have
found the GAITLAB software useful. Of course I had to write a bunch
of linking software and I also wrote software to calculate powers,
average across files and plot these results.
I would be welcome to share my experiences with you.
Michael Raymond Pierrynowski, Ph.D.
Human Movement Laboratory
School of Occupational Therapy and Physiotherapy
McMaster University, HSC 1J11
Hamilton, Ontario L8N 3Z5
CANADA
1 905 525-9140 x22910 (PHONE)
1 905 522-6095 (FAX)
PIERRYN@FHS.CSU.MCMASTER.CA (INTERNET)
Colin,
I have a version of the Gaitlab software (Vaughan et al), but
do not use it for any real data. My use is simply for class
demonstrations, etc. (undergrad 'lab' work). There does seem
to be a problem with timing of events, especially with the
stick figures. For example, on page 69 of the accompanying
text the toe-ons and toe offs for the stick figures do not
line up with the LHS and RTO of the EMG diagrams below it.
I have seen other similar timing problems, but am unable
to come up with a specific example at this point. I have
not contacted Human Kinetics about my observations. What
problems have you experienced? Maybe with many inquiries
to Human Kinetics we can get some explanations.
Jeff Ives, PhD
Dept. Exercise Science
Campbell University
Buies Creek, NC 27506
email: jives@camel.campbell.edu
----------------------------------------------------------------------
Thanks again to all the replies, and especially to the authors of
GAITLAB for clearing up my problem.
Colin Paranchych
University of Alberta
Department of Mechanical Engineering