One of my students is doing a minor senior Mechanical Engineering design
He has provided a brief description below.
He requested me to post this on his behalf.

Our group is trying to redesign the Chicago Elevated train turnstiles.
For our design it is necessary to find out the strength of a small child's
head. The childs age of concern would be from 4 to
10 years old. We need to find out the force required that would
damage the childs skull. With this information it
will then be possible to calculate the safe spring pressures necessary to
avoid such damage caused by the turnstile arm.
Sometimes the childs neck is also wedged between the turnstile
arm and the turnstile base in which case the child suffocates before there
is an opportunity to remove them from the mechanism. Any information that
can be supplied in reference to either the strength of the skull or the
pressure to collapse the airway would be appreciated. Thank-you Greg

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Raghu N. Natarajan
Department of Orthopedic Surgery
Room 1463 Jelke SC
Rush-Presbyterian-St.Luke's Medical Center
1653 West Congress Parkway, CHICAGO, Illinois 60612
Telephone : (312) 942 5367
Fax : (312) 942 2101
e-mail : (1)
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