As a part of a review of preliminary accident investigations, performed by the NHMRC Road Accident Research Unit of the University of Adelaide in conjunction with their Investigation of Traveling Speed and the Risk of Crash Involvement, it became apparent (from case CN01595) that the task would involve the reconstruction of some vehicle/pedestrian accidents. Therefore the following is a brief review of topics related to pedestrian impact reconstruction:
The investigation and reconstruction of vehicle/pedestrian impacts consists primarily of the determination of the occupant “throw” or launch distance. The “throw” or launch distance is that distance that a person or object has been projected from an impact. The distance should include the total distance from impact to rest. There may be some travel on the ground subsequent to a landing after the primary impact event.
Extensions to simple projectile motion equations permit the accident investigator to determine the speed required at the point of impact to produce a specific “throw” distance. However before equations can be applied and a reconstruction can be performed, the reconstructionist must determine the approximate “throw” or launch distance. This entails the determination of the impact point and points of rest for the vehicle and occupant.