Factors Contributing to Front-Side Compatibility: a Comparison of Crash Test Results

The occupants of passenger vehicles struck in the side by another vehicle are more likely to be fatally injured than are occupants of the striking vehicle. The risk of fatality in a side struck car is higher still when the striking vehicle is a pickup or utility vehicle rather than a passenger car of the same mass. This suggests there are other factors inherent to pickup and utility vehicle design in addition to mass that contribute to this increased risk. In this paper, results are presented from a series of six 90-degree front-to-side crash tests conducted with both vehicles moving. The side-struck vehicle, a Mercury Grand Marquis with a BioSID (biofidelic side impact dummy) in the driver position, was moving at 24 km/h (15 mi/h) in all tests. The striking vehicles, moving at 48 km/h (30 mi/h) in all tests, included a passenger car, a baseline pickup with greater front-end stiffness than the car but of comparable mass and ride height, a pickup with increased mass, a pickup with increased ride height, a pickup with increased mass and ride height, and a pickup with increased mass, ride height, and stiffness. The effects of these variations in striking vehicle characteristics were evaluated in terms of the struck and striking vehicles' deformation patterns and accelerations, as well as dummy injury measures and kinematics. Results from these six tests show that increasing the mass and ride height of the striking vehicles produced deeper deformation of the struck vehicle and increased the likelihood of injury, as measured by the BioSID. In addition, the increased hood height of the striking pickups, compared with the striking car, resulted in driver head contacts with the hood as an additional potential source of injury. Increasing the front-end stiffness of the striking vehicles, which was varied by selecting vehicles with different stiffness characteristics, also resulted in deeper deformation of the struck vehicle, but effects on dummy injury measures were inconsistent. These findings suggest that variations in vehicle front-end geometry and associated localized stiffness differences, which could not be separated from overall stiffness in this study, critically affect the outcomes for occupants of the struck vehicle.