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A comprehensive analysis method for assessing the vehicle impact speed in a vehicle/pedestrian collision was presented in an earlier publication (SAE #2000-01-0846) by the above authors [1]. This presented method provides a practical analytical approach for evaluating vehicle impact speed from the post-impact vehicle damage, pedestrian injuries and pedestrian throw distance. The applicability of this method to reconstructing real world vehicle/pedestrian collisions is examined. The results of this study indicate that the previously presented model can be used to assess a reasonable range for the vehicle impact speed in a vehicle/pedestrian collision. The regression model equations were revised to include the new data.

This paper provides a reference for “real world” walking speeds of young pedestrians. The subjects of the study were unaware elementary school children crossing at marked crosswalks adjacent to elementary schools. The unaware pedestrians were videotaped at 30 frames/second with a camera hidden in a parked vehicle that was not visible from the crosswalks. The pedestrians' constant walking speeds were ascertained from analysis of the video recording. The walking speed data was categorized according to gender, estimated age, number of pedestrians in a group and time of day. The observed trends were compared to data from existing studies.

This study presents an efficient method for forensic engineers to determine the expected forward knee and hip displacements of automobile occupants who are restrained by seat belts during frontal impacts. The amount of knee displacement sustained by an occupant in a vehicular collision must be determined in order to assess seat belt usage and benefit. The results of this study may be referenced to model the lower body motion of vehicle occupants in frontal impacts for a range of impact severities. Previous research has empirically determined hip and limited knee displacements for subjects restrained in frontal impacts of specific severities; however, these research results have not been directly compared to produce a simple and practical model that is applicable for a range of collision severities.

This paper presents a comprehensive method for assessing the vehicle impact speed in a vehicle/pedestrian collision. Mathematical models, real world collision data and staged impact test data were referenced from several studies pertaining to pedestrian collisions. Applicable relationships comparing vehicle impact speed to pedestrian throw distance were developed from regression analyses. In addition, post-impact vehicle damage and pedestrian injuries were subjectively analyzed to assess trends in vehicle impact speed. These methods provide a practical analytical approach for evaluating vehicle impact speed from the post-impact vehicle damage, pedestrian injuries and pedestrian throw distance.

This paper quantifies the deceleration of motor vehicles as they were routinely stopped for an expected hazard in a real world environment. It was observed that the deceleration rate varied non-linearly, with a peak value of about 0.25g as the vehicle decelerated through the speed range of 20 to 30 km/h. This deceleration pattern was common to all evaluated categories of passenger vehicles. A mathematical model was developed to define the deceleration profile; enhancement of this model yielded predictive relations for the velocity, position and remaining braking time of decelerating passenger vehicles.

This paper presents a practical analytical approach for evaluating sideswipe collision severity from residual vehicular deformation. A simplified mathematical procedure was developed to evaluate vehicular speed changes, effective average vehicular acceleration rates and the collision duration from measurements of vehicular damage. Several series of sideswipe collisions were staged to acquire empirical sliding contact data. The results of this testing were employed to provide a preliminary validation of the proposed analysis model. The limited validation supported the use of the proposed analysis technique to assess a vehicle's speed change resulting from a sideswipe collision.