Determination of Vehicle Crush from Two Photographs and the Use of 3D Displacement Vectors in Accident Reconstruction

Given two or more photos of an accident vehicle (non-stereo pairs such as police photos) an estimate of the deformation (crush) of the vehicle may be obtained by application of camera reverse-projection, using two or more cameras and an exemplar vehicle. A single camera technique familiar to accident scene investigators is modified for this application. The methodology is described within the context of an experiment comparing results obtained by camera reverse projection to actual measured crush.

A method of displaying crush results known as “displacement vectors” is presented and examples are illustrated. The technique has been found useful for measurement of 3-dimensional crush.

This paper describes the two-image camera reverse-projection method, for determining automotive, accident-caused crush; procedures for applying this method including insights from the authors practical experiences; and a case-study example where results obtained from this method were compared to actual crush measurements.