My dissertation concerned measuring the forces on bicycle saddles. Since
the saddle is not a planar surface, this was not an easy task. I tried
several different methods - which failed - before fabricating 3 different
transducer mounts congruent with the saddle shapes under consideration. I
used a piezoelectric crystal made by Kistler as the transducer. The
dimensions and preload characteristics of this transducer precluded the
design of the transducer mounts. One reference that I found helpful was
"The Bathroom" by Alexander Kira, 1976, but there really were not any good
references. I attended a course "Pressure on People" put on by the
Veterans Administration which was helpful. You are always welcome to
refer to my dissertation which is in the public domain through
interlibrary loan: "Distribution of Cycling-Induced Saddle Stresses" by
Martha Jack, Washington State University, 1981. I have gone to great
length to describe how the transducer mounts were fabricated such that it
can be replicated. If you which any further information, just ask.

__________________________________________________ ____________________
Martha Jack, Ph.D. E-mail:
Biomechanical Engineer Voice: (509) 943-0043
___o P.O. Box 776 FAX: (509) 943-4642 ___o
_ \ looking for information on the contours of human-seat interfaces.
> That is, the shape of the seat which conforms to the human form.
> There is much data on antrhopometric dimensions and
> some on contours, but I have been unable to find much on the
> contours of the seat that occur while sitting. Are there any
> instruments capable of measuring these contours through time besides
> by "casting" shapes at certain points in time ?
> with thanks
> Neil Tuttle
> Griffith University
> Gold Coast