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Steven M. Schorr, PE ::::

You are presented with an intersectional collision case and you determine that someone’s sight line was blocked, so you hire an investigator to run out to the scene and take photographs.  You hoped that these photographs sufficiently represented the views of the drivers such that your expert could scientifically substantiate sight distance opinions.  You relied on these two-dimensional photographs being taken at the proper eye height and at the proper location on the roadway such that they could be placed in evidence at court.  However, often times, these photographs do not sufficiently depict everything necessary to “make” your case.  What is the easy answer to this all too common problem?

We live in a three-dimensional world so you need to be sure your engineer is working in that same three-dimensional world.  Short-lived data at collision scenes can easily and quickly be documented utilizing high-definition surveying (HDS) laser scanning.  This cutting edge technology can document the sight and site conditions of an entire intersection in less time than it takes to watch the latest episode of CSI.  The cost is no higher than if you had hired a full survey crew to perform a site survey.  The data collected by the HDS laser scanner is often so dense (i.e., there are so many measurements) that the raw “point cloud”, without any computer modeling, can be used for the analysis.  Additionally, if there was a delay in getting the HDS laser scanning field crew to the site and the site had been changed (i.e., someone cut down the buses or tree), if there were two-dimensional images of the site (photographs), the accurate, to-scale, three-dimensional environment created by the HDS laser scanner can be utilized as a foundation for three-dimensional photogrammetry to accurately replace, to scale, portions of the bushes and/or trees that have been trimmed.   To keep up with our technically changing world, you need to think in three-dimensions.  You should expect your experts to do the same.

, with DJS Associates, Inc., can be reached via email at experts@forensicDJS.com or via phone at 215-659-2010.