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Crash Test Dummies...
Crash test dummies first arrived on the scene in 1949 for the U.S. Air Force. The Air Force
needed a way to test ejection seats from airplanes, but the technology was getting so sophisticated that it became
dangerous to continue using human volunteers. They needed something that would simulate human reactions without
using live human beings. The name of their first test dummy was Sierra Sam.
Between the time of Sierra Sam’s invention in 1949 and 1966, there was no set standard in
dummies that were being produced. They were all different which made it very difficult to collect reliable data.
They were also only being used to test airplane ejection seats and airplane seatbelts. In 1966 a new dummy was
produced that was specifically made to test automobiles. This revolutionized the car manufacturing industry because
they could now begin to test the effects of crashes on the human body. General Motors became the leader in crash
test dummy technology by producing Hybrid I, Hybrid II and in 1997 Hybrid III. With each new model, the data has
gotten consistently better. All dummies take on the human form in weight, size and proportion. There are many
different sizes as there are many different sized people. They have spines made out of metal discs and rubber
padding, necks that move, a steel rib cage and knees that respond to impact like a human knee would. On top of
these traits, the Hybrid III also has vinyl skin with electronic sensors which measure the forces that different
body parts can experience during a crash.
Before a dummy is placed in a car, they are given outfits to wear. Wearing clothes allows
them to slide on the car seat as a human might. When a dummy is placed in a car, researchers apply paint to various
body parts. Different colors are used for different areas of the body. This way, when the researcher crashes the
car, they can then look at the amount of paint that transfers from the dummy’s body to parts of the car. If, for
instance, red paint is placed on the dummy’s knee and after the crash there is a lot of red paint on the steering
wheel, the researcher knows that the placement of the steering wheel should be adjusted in order to prevent knee
injuries.
Researchers also collect data from sensors that are placed inside the dummy. There are three
different kinds of sensors; accelerometers, load sensors and motion sensors. Accelerometers measure how fast a body
part moves upon impact. For instance, if you hit something hard, like a brick wall, your head will move very
quickly, but if you hit something soft like a pillow, it will move more slowly because the impact is
absorbed.
Accelerometers are placed inside the dummy’s head, chest, pelvis, legs and feet. Load
sensors measure how much force is being placed on the body of the dummy upon impact. This measure of force can be
used to determine how much load a bone can take before it breaks. The movement sensors are placed in a dummy’s
chest. This measures how much the chest can deflect. In other words, it can tell the researcher how much the chest
can be pushed in without causing life-threatening injuries.
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