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The purpose of this paper was to compare the damage to pickup truck bumpers produced by vehicle-to-barrier and vehicle-to-vehicle collisions of a similar severity, in order to determine whether vehicle-to-barrier tests can serve as surrogates for vehicle-to-vehicle tests in accident reconstruction. Impact tests were conducted on the front and rear bumpers of five pickup trucks. Each truck was subjected to an impact with a fixed barrier and with a passenger vehicle. All impacts resulted in pickup truck speed changes of about 8 km/h. Damage produced in the barrier and vehicle-to-vehicle collisions was similar if both collisions resulted in bumper mount damage on the pickup truck. If there was no bumper mount damage, then the bumper beam deformation depended on the shape of the impactor.

The severity of low-speed front and rear impacts is commonly assessed through testing of the actual or exemplar vehicles or by comparison with available barrier test data. While tests conducted on actual or exemplar vehicles are most accurate, barrier testing also provides dynamic properties of the bumper isolators in a controlled manner. The goal of this paper was to determine if barrier testing of a single isolator can be used to assess the behavior of an intact bumper on an actual vehicle. Replacement bumper isolators for 15 vehicles were individually mounted to a moving barrier and subjected to low-speed impacts with a fixed barrier to correlate their dynamic compression with impact severity. The single isolator results were compared with actual vehicle barrier test results. A total of 1624 tests were conducted. A 2nd order linear spring-mass-damper model was used to predict impact severity characteristics of the actual vehicle from the single isolator data.

During vehicle collision testing an accurate measure of the pre- and post-impact vehicle dynamics is necessary for analytical purposes. Sensors typically used for measuring vehicle speed change in low-speed collisions include 5th wheels, high-speed video, bumper-mounted load cells, and accelerometers. The method used is often based on equipment availability, the involved vehicles, and the type of tests being performed. The purpose of this paper was to quantify the relative accuracy of these four methods in aligned low-speed rear-end collisions. Data from 73 such collisions (clustered in two groups at target vehicle speed changes of 4 and 8 km/h) showed that all four instruments yielded statistically similar results for a target vehicle speed change of about 4 km/h, and that data derived from the 5th wheel and high-speed video were different than data from the other two sensors at the 8 km/h level.

Accurate assessment of the severity of a low speed impact between two vehicles can sometimes only be accomplished through staged collisions with the actual or exemplar vehicles. However, the cost of obtaining, colliding, then repairing the vehicles often precludes this option. For this paper, two prototype moving barriers were constructed to test three different bumper assemblies separate from their vehicles. Candidate bumper assemblies were mounted to the moving barriers for low speed impact testing with a stationary barrier and three other vehicles. Forty three test series of 701 total impacts were done to compare bumper performance in moving barrier tests with their in-situ counterpart. Vehicle-to-fixed barrier, vehicle-to-vehicle, moving barrier-to-fixed barrier and moving barrier-to-vehicle tests were done using four different vehicles. The actual vehicle and moving barrier results were statistically compared.