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The purpose of this study was to determine if quasi-static (QS) bumper force-deformation (F-D) data could be used in a low-speed bumper-to-bumper simulation model (1) in order to reconstruct low-speed crashes. In the simulation model, the bumpers that make contact in a crash are treated as a system. A bumper system is defined as the two bumpers that interact in a crash positioned in their orientation at the time of the crash. A device was built that quasi-statically crushes the bumpers of a bumper system into each other and measures the compression force and the deformation of the bumper system. Three bumper systems were evaluated. Two QS F-D measurements were performed for each bumper system in order to demonstrate the repeatability of the QS F-D measurement. These measurements had a compression phase and a rebound phase. A series of crash tests were performed using each bumper system.

The costs of low-velocity, front-to-rear crash tests include the bullet (striking) and target (struck) cars. Analyses of this type of tests led us to conclude that it may be technically feasible and economically advantageous to replace the bullet car with a simplified mechanical device. A bifilar pendulum with an impact face consisting of a mass-spring-damper system was designed to simulate the bullet car in car-to-car, collinear, low-velocity (delta-v <= 8 km/h) front-to-rear tests. The elements of the pendulum face were evaluated dynamically and quasi-statically. Also, car-to-car tests were initially performed with stationary target cars (brakes off). Repair or replacement of the minor damage observed in the cars was accomplished as needed. Tests were subsequently performed with the pendulum striking the same target cars and approximating the bullet cars' impact energies. The pendulum, bullet, and target cars were instrumented with translational acceleration and velocity sensors.

The purpose of this study is to determine the loads in the long bones of the lower extremities during vehicle pedestrian impact tests, and to correlate load data with observed kinematics in an effort to understand how stature and vehicle shape influence pedestrian response. In tests with a large sedan and a small multi-purpose vehicle (MPV), four postmortem human surrogates (PMHS) in mid-stance gait were struck laterally at 40 km/h. Prior to the tests, each PMHS was instrumented with four uniaxial strain gages around the mid-shaft cross section of the struck-side (right) tibia and the femora bilaterally. After the tests, the non-fractured bones were harvested and subjected to three-point bending experiments. The effective elastic moduli were determined by relating the applied bending loads with the measured strains using strain gage locations, detailed bone geometry, and elastic beam theory.