A significant number of vehicle-to-vehicle collisions involve front-to-rear impacts at low- to moderate-speeds. While a variety of studies have been conducted since the 1990s involving fore-aft collisions, those discussing the response of late model passenger vehicles during progressively more severe impacts are limited. In this study, four inline, front-rear tests were conducted using two midsize sedans of the same make, model, and year. An instrumented Hybrid III 50th percentile-male Anthropomorphic Test Device (ATD) was located in the driver seat of each sedan and was restrained using the standard three-point seat belt system. Instrumentation on the vehicles included tri-axis accelerometers and seat belt load cells.
For each test, the centerlines of the vehicles were aligned, and the striking vehicle impacted the stationary target vehicle at closing speeds of 4.6, 7.9, 13.5, and 20.9 mph (7.4, 12.7, 21.7, and 33.6 kph). The front and rear bumper covers were removed to allow the response of the bumper systems to be observed during the impact. Vehicle and ATD data were recorded using on-board data acquisition while on- and off-board real-time and high-speed video cameras captured each test from varying perspectives. In addition, post-impact deformation was quantified from three-dimensional scan data and photographs.
Data evaluated included vehicle accelerations, change in velocity (Delta-V), restitution, and energy dissipation. Force-displacement curves were developed and compared, and progression of vehicle damage was discussed. Finally, the accuracy of frontal stiffness characteristics derived from barrier testing for predicting energy dissipation in low- to moderate-speed collisions was assessed.