Use of photogrammetry as a tool for accident investigation and reconstruction : a review of the literature and state of the practice.

154724287Final report.PDFTech ReportVTRC 07-R36VirginiaVirginia Transportation Research CouncilArnold, E. DVirginia Transportation Research CouncilVirginia. Dept. of TransportationUnited States. Federal Highway AdministrationUS Transportation CollectionOne of the key goals of incident management is the rapid clearance of traffic incidents. Many transportation agencies focus their incident management on quicker and more reliable detection techniques. Another focus, however, should be the reduction in time required by law enforcement officers to complete on-scene investigations of crashes. As the price of high-quality digital cameras has steadily declined, more agencies are beginning to use photogrammetry as a method for accident investigation and reconstruction. The investigative time needed for certain crash sites is reduced because taking photographs is quicker and simpler than employing other methods typically used, such as coordinate and the total station survey method. Pictures are taken at the site and then brought back to the office and analyzed to obtain measurements of the scene. The analysis can be very time-consuming; therefore, the trade-off for reduced field time and road closure time is increased analysis time. Many law enforcement agencies in Virginia, including the Virginia State Police, use the total station survey method for accident investigation and reconstruction. Its main disadvantages are its relatively high cost and complexity, with the latter necessitating extensive training on how to use the system. Because of these factors, it is often the case that only a few systems and operators are available. Given the commitment of the Virginia State Police and other law enforcement agencies to total stations, the purpose of this study was to determine if photogrammetry is a valid tool for accident investigation and reconstruction in Virginia. The scope was limited to reviews of the literature and the state of the practice. Findings and conclusions are provided regarding the use of photogrammetry in Virginia and the United States, its advantages and disadvantages, associated legal issues, and its cost. The report recommends that the Virginia Department of Transportation in conjunction with the Virginia State Police undertake several case studies of accident investigation and reconstruction at either mock or real crash scenes in which both total station and the most current photogrammetry methods are used and compared