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The collection of research regarding occupant kinematics during low speed lateral vehicle-to-vehicle impacts is far less comprehensive than the much larger body of literature that quantifies the occupant kinematics associated with low speed rear end (longitudinal) impacts. In order to augment the available data, a series of 39 low speed far-side lateral vehicle-to-vehicle impacts were conducted in a laboratory setting. A combination of accelerometers and 3D motion tracking was used to characterize the motions of both the Target and Bullet vehicles during their collisions. The Target vehicle was initially stationary; the Bullet vehicle impacted the Target vehicle at the front passenger side door. The Bullet vehicle pre-impact speeds across all tests ranged from approximately 2.5 to 5.5 mph (4.0 to 8.9 kph; 1.1 to 2.5 m/s). Eight volunteers participated in the study.

This aim of this study was to introduce and test three different design enhancements to the contrast-sensitivity charts developed by Ayers and Kubose [1]. Contrast-sensitivity charts are the current, critical instrument for generating photographic representations of low-illumination scenes. However, their range of applicability is limited to a specific range of lighting conditions for any given scene, and a limited set of testing and perceptual conditions for observers. A total of four contrast charts were presented to ten dark-adapted observers in nine different lighting conditions that changed in ascending order from low to high levels of illumination. For each lighting condition, the order and orientation of the charts was randomized. Observations related to the number of detected contrast levels were then compared to find the utilization ranges for each chart.

A complete analysis of any vehicular collision needs to consider certain aspects of human factors. However, this is especially true of nighttime collisions, in which a more specialized approach is required. Classical collision investigation (frequently referred to as accident reconstruction) is comprised of kinetic and kinematic considerations including skid analysis, momentum techniques and other methods. While analysis based on these concepts is typically unaffected by low visibility conditions, the opposite is true of the perceptual and cognitive aspects of a “humans-in-the-loop” analysis, which can be enormously impacted by low visibility. Only by applying appropriate human factors techniques can the analyst make a defensible determination of how and why a nighttime collision occurred.