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Dummies: Past & Present by Joe Smrcka
Introduction
Naked man is a fragile creature who must continually avoid harsh environments.
When clothed, he can function in less favorable conditions, but he remains extremely
vulnerable to blows, impacts, and accelerations. In early historic times, protective
systems such as soldiers shields were devised and later elaborated into full suits of
medieval armor. The growing severity of environments rendered such protection primitive
indeed, and even before the advent of the space age, the concept of human packaging
within vehicles was introduced.
Today the packaging of the human to minimize or avoid injury is a major undertaking.
Automotive and cockpit interiors are designed in conjunction with restraint systems to
help safeguard the occupant. Ejection seats and capsules are in regular use to counter
the numerous hazards of escape from high-performance aircraft. Highly sophisticated
energy-absorbing couches are used to attenuate impact forces which astronauts may encounter.
In spite of the huge effort devoted to the development and improvement of protective
systems, one essential link has been weak in the protective chain. All of these protective
efforts are centered about a single object, the human body; but no human body is really
available to test concepts and evaluate systems, except at low energies because of the
unacceptable risks to subjects. Most needed, a real human subject would perish.
In the attempt to make valid tests of protective systems, engineers and scientists have
turned to many alternatives. Cadavers have been employed as test subjects, in spite of
the many problems created by their use, because they are the closest available substitutes
for the living human. Cadavers have served certain functions in test work, but cadaver data
has fallen short due to their scarcity. Chimpanzees, hogs and other animals have served as
automotive passengers and cockpit occupants, but their dissimilarity to the human is far too
pronounced and their capability for internal instrumentation far too limited to produce
meaningful data.
Anthropomorphic test devices, commonly referred to as "dummies", have been the most widely
used subjects for testing protective systems. The early, conventional dummies had only limited
utility. While approximating human kinematics and providing acceleration and other data applicable
to corresponding humans, such testing has not generally measured the stresses imposed upon the
human in the test situation and could only roughly determine the potentials for severe or fatal
injury associated with such stresses. These deficiencies led to the development of dummies with
improved biofidelity (the degree to which pertinent human physical characteristics are incorporated
in the dummy design) and greater measurement capacity. While some efforts have been made to develop
an omni directional dummy, most of the effort has been directed toward developing separate dummies
for frontal and side collision auto testing. These dummies are classified as "frontal impact
dummies", "Side Impact Dummies" and, in addition there are "Aerospace Dummies." The dummies are also
classified according to their physical size. The mid-size adult male dummy, the most utilized in
automotive restraint testing, approximates the median height and weight of the U.S. adult male
population. The small female and large male dummies approximate the height and weight of the
fifth-percentile female and 95th percentile adult male. Heights and weights of child dummies
approximate median heights and weights of children of the specified age grouped, without regard
to sex.
The following chapters provide description of past and present dummies, their intended application,
design specifications, physical characteristics, biofidelity levels and measurement capabilities.
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