In the field of accident reconstruction, it is often important to measure the deformation of a vehicle (i.e. automobile, truck, motorcycle, etc.) after a crash has occurred. This data can be used for many purposes including energy calculations for speed loss, measuring roof or other structural deformation, analyzing seat or seat belt component positions, frame or unitized body structure deformation, and for estimating the actual post crash condition of a vehicle prior to the damage inflicted by the cutting and spreading tools used by emergency personnel. Traditionally, vehicle damage was measured using plumb bobs and tape measures or laser transits. However, these methods are not only time consuming but they also require a significant amount of upfront analysis to determine which points on the vehicle to measure at the inspection. In recent years, newer methods such as photogrammetry software and three dimensional scanners have come into play. Companies like FARO, Leica, Riegl, Trimble and Surphaser have developed these three dimensional laser scanners which can be used to efficiently document vehicle damage with millions of data points. The laser scanner equipment is simple to setup, collects data quickly and is accurate to a few millimeters.
This paper describes the three dimensional scanning equipment and outlines a methodology of how to set it up at the vehicle inspection, how to process the voluminous data generated by the scanner, and then several case studies are presented showing how the data can be used in reconstructing crashes. The FARO Photon 80 scanner is used in examples.