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This paper describes the development of an improved neck simulation that can be adapted to current anthropometric dummies. The primary goal of the neck design is to provide a reasonable simulation of human motion during impact while maintaining a simple, rugged structure. A synthesis of the current literature on cervical spine mechanics was incorporated with the results of x-ray studies of cervical spine mobility in human volunteers and with the analysis of head-neck motions in human volunteer sled tests to provide a background for the design and evaluation of neck models. Development tests on neck simulations were carried out using a small impact sled. Tests on the final prototype simulation were also performed with a dummy on a large impact sled. Both accelerometers and high-speed movies were used for performance evaluation.

A new crash test device has been developed, called “Repeatable Pete.” It is a repeatable, durable anthropomorphic dummy with humanlike dynamic performance. This paper describes the device and gives details of its design and performance during testing in automotive situations. The head, neck, and chest match the latest biomechanical information on the dynamic responses of unembalmed cadavers. The head c.g. accelerations adequately match the skull acceleration, so that head injury criteria based upon cadaver skull acceleration may be used.

A study of the biomechanical factors concerned with the design of side structures and doors for crashworthiness has been made. Questions regarding optimum stiffness, location of reinforcing members, effect of armrests, and padding have been answered within the framework of injury criteria models. Results of animal studies, cadaver studies, and anthropometric dummies have been combined to produce injury criteria for lateral impacts to the head, thorax, and abdomen. Impacts were applied utilizing a specially designed “air gun” in a laboratory environment emphasizing reproducibility and control. Full-scale crash simulations were performed on an impact sled to verify the results of the more specialized tests and analyses. Scaled models of current production doors were used in the animal series. Scaling relationships for various species of animals have been developed and extrapolated to man. Significant differences in right and left side tolerances to impact were noted and detailed.

This paper has utilized a specially created subset of the data contained within the National Accident Sampling Study (NASS) for an updated and expanded analysis of the relationship between Delta V and injury. The data presented embrace over 20,000 accidents of passenger cars, light trucks and utility vehicles involved in accidents between 1980 and 1991. These unique accidents have been extracted from the massive amount of available information contained within the NASS data in order that the variables which have the greatest information content for our subject can be studied and analyzed. Some of the variables which were extracted and studied include Delta V, Principle Direction of Force, restraint system type and use, injuries, vehicle weight and type as well as the occupant variables of age and sex which are believed to influence human tolerance to injury.