I have acquired a lot of three axis accelerometer data (at 1000
samples/sec)of roller coaster and automobile environments.
I would like to see reputable papers or information on acceleration
and jerk (the delta, derivative of acceleration) and how it affects
the human body.

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Request for Question Clarification by davidmaymudes-ga on 10 Oct 2002 00:30 PDT

I can see three different topics here--information about relatively
low accelerations and whether people are comfortable undergoing them,
information about moderately high accelerations (5g or so) and the
possible health effects, or information about very high accelerations
(such as in an automobile accident) and the immediate injuries they
can cause....  is there one of these that is of particular interest,
or would you rather hear a little about all three?

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Clarification of Question by cgb2-ga on 10 Oct 2002 08:53 PDT

I have found a lot of info on sustained acceleration, such as a jet
pilot would feel, but I am specifically interested reports of the
biomechanical effects of jerk (rapid changes in acceleration) at less
than 5g.

Thanks for quite the interesting question!

The engineer in me understood exactly what you were looking for when
you spoke of "jerk", but I had a feeling that Google might choke on
the term. Substituting "step input" narrowed the field somewhat, and
gave me the lead that seems to be the jackpot for your interests;
Impact Biomechanics, which deals "with transient events of very short
durations (<100 ms)".

Impact Biomechanics is a growing field, with at least one major
laboratory (Virginia Tech; http://www.ibl.vt.edu/) devoted solely to
its research. Its significance has also been recognized by many
research bodies, including the Society of Automotive Engineers. While
"classical" Biomechanics typically deals with the human body as a
rigid network of interconnected parts, Impact Biomechanics takes into
account the unique materials properties of the human body when
subjected to drastic acceleration.

It seems as though this is a very young field, and a good deal of the
literature I was able to find dealt with head and neck injuries
associated with automobile accidents. While the forces in such and
accident may be beyond the 5g threshold of your clarification, my
guess is that the analysis methods would still be applicable. I hope
this proves to be true.

I have listed the Google search terms used as headings for the site
listings found below. For the SAE link, the search was performed on
their website specifically. The SAE books listed are compendia of
research papers for the subject described in their respective titles
and dating from the mid 1960's onward. The Virginia Tech research site
has links to locally generated information, and is broken down based
on body region. The RAAPA (Russian Association of Amusement Parks and
Attractions) sites listed are specific to safety issues concerning the
biomechanical reactions to roller coasters.

If it turns out that this is *not* what you're after, please do ask
for clarification, and I'll be happy to provide what I can. Thanks
again!

jickster-ga


*Search Terms and Relevant Links:

*STEP INPUT ACCELERATION BIOMECHANICS:

http://auto-safety.mech.virginia.edu/DatabaseConnection/
Papers/DarvishASME1998.pdf
-- Title: A DYNAMIC METHOD TO DEVELOP NONLINEAR VISCOELASTIC MODEL OF
BRAIN TISSUE

http://www.mvd.chalmers.se/csd/sekt.PDF
-- Title: Impact Biomechanics and its importance to reduce health
losses and costs from road accidents

*IMPACT BIOMECHANICS:

http://www.ibl.vt.edu/
-- The Impact Biomechanics Laboratory at Virginia Tech

http://www.ibl.vt.edu/research.htm
-- Research information on varying types of human impact injuries


*IMPACT BIOMECHANICS ROLLER COASTER:

http://www.raapa.ru/saftoc_eng.shtml
-- Title: Allowable G-Loads for Amusement Ride Passenger

http://www.raapa.ru/saftoc1_eng.shtml
-- Title: POSSIBLE CAUSES OF HEADACHES AFTER MULTIPLE RIDES ON A
ROLLER COASTER


http://www.sae.org -- search: *impact biomechanics:

http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=SP-1665
-- Book Title: Impact Biomechanics

http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=PT-45
-- Book Title: Biomechanics of Impact Injury and Injury Tolerances of
the Thorax-Shoulder Complex

http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=PT-56
-- Book Title: Biomechanics of Impact Injury and Injury Tolerances of
the Extremities

http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=PT-47
-- Book Title: Biomechanics of Impact Injuries and Injury Tolerances
of the Abdomen, Lumbar Spine, and Pelvis Complex

http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=PT-43
-- Book Title: Biomechanics of Impact Injury and Injury Tolerances of
the Head-Neck Complex

While the bumper of the vehical may suffer 100g for 1/10 second;  s=
1/2 at squared = 16.1 feet, the displacement of the occupants neck is
some what greater due to crumpling of the vehical, and the time is
streached out at least a bit. If the headrest seatbelts, dash
cushions, and air bags keep the body displacement sychronized with the
neck displacement the pasenger may survive, instead of having their
head snaped off. The acelerometers need to be fastened to the neck etc
of the crash dummies, or so it seems to me.  Neil