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When vehicle-specific stiffness coefficients cannot be acquired, stiffness coefficient values that are representative of the desired vehicle type, class, wheelbase or weight are routinely used for accident reconstructions. Since the original compilation of representative vehicle stiffness data almost 20 years ago, changes in crash testing standards and other safety and technological improvements in vehicular design have affected vehicle stiffness. While generic frontal stiffness data have been recently updated to reflect these vehicular changes, rear and side stiffness data have not. Structural, geometric and inertial data for over 300 passenger cars and light trucks were collected. Among the vehicles targeted were the top-selling cars, SUVs, vans and pickups for model years 1990 to 2012. Results indicated that all vehicle types demonstrated increases in mean stiffness over the time period considered. SUVs were, on average, the stiffest vehicle type in the front, rear and side.

An experiment was conducted to examine the validity of freely available photo-based 3D scanning software for generating accurate 3D geometry of a vehicle. Currently, 3D vehicle geometry is routinely captured using total station survey equipment, coordinate measuring machines (CMM), laser scanning, or traditional point-based photogrammetry. While these methods produce sufficiently accurate results for collision reconstruction, they have limitations that can affect practical implementation. For example, manual surveying with a total station, CMM or traditional photogrammetry are all limited to the production of coordinate data at discrete, pre-defined points. In addition, total stations, CMMs and laser scanning devices are also expensive and require a significant amount of time in the field with the vehicle. In contrast, photo-based 3D scanning allows a 3D mesh to be created of a vehicle simply from a series of photographs using a consumer-grade digital camera.

Dynamic simulation is routinely used to analyze the occupant response to motor vehicle impact. That said, while commercially-available models have been subjected to numerous high-severity level validation studies, little attention has been given to lower severity crashes. While high severity crashes typically result in more severe injury, the vast numbers of lower severity “fender bender” type crashes and the ensuing high medical costs warrant study related to biomechanics and vehicle design. The scope of this study is directed at addressing the validity of these models for analyzing occupant response to collinear rear impact involving delta-V less than 5 mph. As part of this study, a series of five vehicle-to-vehicle collisions with instrumented volunteer occupants were performed with closing speeds of 1.1, 1.9, 2.9, 4.0 and 5.1 mph. These impacts produced delta-V, for the target vehicle, of 0.6, 1.8, 2.5, 3.1 and 3.2 mph, respectively.