View Full Version : Trunk modelling

Christian Lariviere
07-24-1995, 07:39 AM
Below is a summary of the replies I received concerning my question
about the position of the trunk center of mass (see the first
message). To those who responded: Thank you very much!


I am a PhD student at the U. of Sherbrooke (Quebec, Canada) and we
are trying to validate our dynamic 3D multisegment model. We are
comparing the results of 2 dynamic methods to estimate triaxial net
reaction moments at the L5/S1 joint (upward and downward methods)
depending of the initiation of the external forces (from the feet or
from the hands).
Our results with static tasks suggest that the positions of the
centers of mass of the different parts of the trunk (pelvic, lumbar
and thoracic sections) are inadequate. We use the data of Zatsiorsky
& Seluyanov (1981, 1983) to estimate their positions along the
longitudinal axis but their antero-posterior positions are unknown.
We tried to locate these centers of mass along a line connecting the
middle of the shoulders to the middle of the hips but the results are
still disapointing.
We would like to find other body segment parameters data who
gives the antero-posterior positions for these 3 separate segments.
We don't know if these data exist. Any comments/suggestions or
references will be grateffully received.
As usual, all the responses will be posted. Thank you!
Christian Lariviere


I am not sure how useful it would be for you but I do know that there is
some data by Lui et al. on the center of mass of transverse slices of the
torso. I think you could recalculate these data to get something like what
you need. They only measured this data on one cadaver however. The paper
was published in Aerospace Medicine, June 1971.

Sara Wilson sew@bihobl2.bih.harvard.edu


Hi, Christian,
The following two references may help you:

1. Clauser, C. E., McConville, J. T., and Young, J. W. Weight, volume
and center of mass of segments of the human body (AMRL technical report
69-70, pp. 46-55, 59). Wright-Patterson Air Force Base, OH.

2. Hinrichs, R. N. Adjuistments to the segment center of mass proportions
of Clauser et al. Journal of Biomechanics, 1990(23): 949-951.

Good luck.

Bing Yu, Ph.D.
Orthopedic Biomechanics Laboratory
Mayo Clinic
Rochester, MN 55905


Dear Christian,

I have been doing some work using MRI to determine inertia properties
of body segments of the lower extremities for NASA. In the past
year, I've tried to become very familiar with the literature. The
best overall reference that I've found is "Biomechanics and Motor
Control of Human Movement", 2nd Ed., by David A. Winter, Wiley &
Sons, 1990. In Ch. 3, he essentially cites a great deal of the work
done in this area.

Both NASA and the Air Force have shown a great deal of interest in
this area. NASA has a publication from the mid-70's called the
Anthropometric Source Book. You may also want to contact Dr. Louise
A. Obergefell, AL/CFBV, Wright-Patterson AFB, OH 45433-6573 USA,
(513)255-3665 or Jennifer J. Whitestone, AL/CFHD, Building 248 2255 H
Street, Wright-Patterson Air Force Base, OH 45433-7022 USA,
(513)255-8870, JWhitestone@Falcon.AAMRL.WPAFB.AF.MIL

Good luck with your work.

Dr. Beth A. Todd
Assistant Professor
Engineering Science and Mechanics
Box 870278
University of Alabama
Tuscaloosa, AL 35487-0278
fax: (205)348-7240


Dear Christian,
One reference which provides centres of mass of body segments related to
superior-inferior and anterior-posterior landmarks is:

Dempster WT & GRL Gaughran (1967) Properties of body segments based on size
and weight. American Journal of Anatomy 120(1):33-54.

Good luck,

Vaughan Kippers PhD
Functional Musculoskeletal Anatomy Group
Department of Anatomical Sciences
The University of Queensland 4072
Voice-Mail +61 (0)7 3652704
FAX +61 (0)7 3651299
E-mail v.kippers@mailbox.uq.oz.au
WWW Location http://www.uq.oz.au/home.html


Dear Christian,
I did have a quick look in the Anthropometric Source Book of the NASA
Edited by the staff of the Anthropology Research Project and Published
by Webb Associates, Yellow Springs Ohio, 1978.
I found data about the mass of the three trunck segments, and about
the COM of the whole trunck, but not about the COM of the separate parts
If you don't know the book, it maybe still usefull for you if you
want to estimate these data or want to measure it.
If you find elsewhere these data, would you please inform me to.
Other possible sources:
Dempster (1955), about which much is cited in the Source book
Spacerequirements of the seated operator:
Geometrical, kinematic, and mechanical aspects of the body with special
reference to the limbs
WADC TR 55-159 Wright Air Development Center, Wright Patterson Air
Force Base, Ohio,254 pages, 172 references, 1955 (AD 878 92)
Roebuck, Kroemer and Thomson (1975) Engineering Antropometric Methods
Wiley, 1975.
I talked with my colleague Pynan Hoekstra, who is responsible for
our manikin ADAPS; he knows more about how we used 15 year ago, data
from Dempster for the design of of the trunck of ADAPS.
PS Pynan can be reached under P.N.Hoekstra@io.tudelft.nl.
With kind regards,
================================================== =================----
Johan F.M.Molenbroek,PhD
Associate Professor Engineering Anthropometry
Deputy Subdepartment Physical Ergonomics
Faculty Industrial Design Engineering
Delft University of Technology
Jaffalaan 9
2628 BX Delft, The Netherlands
voice + mailbox:+31-15783086
voice secr +31-15783029
WEB: http://tudoms.tudelft.nl/~rietkerk/departm.htm
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