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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.

Knowledge about vehicle rolling resistance is required to calculate speed loss of accident vehicles during portions of their pre-impact and post-impact trajectory when they are not braking or sliding directly sideways. The accuracy of assumed rolling resistance values is most important in accidents with long post-impact roll out distances. Very little hard data are currently available1 and the accident reconstructionist must usually make estimates of drivetrain losses and normal and damaged tire rolling resistance to determine overall vehicle rolling resistance. In the first part of this study, the rolling resistances of various vehicles with different drive configurations are determined, based on accurate measurements made with a 5th wheel. In the second part, sensitivity analyses are done with PC-Crash2, a computer simulation program, to determine what effect the error in assumed rolling resistance has on speed calculations for various types of post-impact trajectories.

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.