Analyzing Motor Vehicle Traffic Collisions Based Upon The Damages To The Involved Vehicles Has Become A Commonly Accepted, Accurate And Reliable Form Of Engineering Analysis. Until Recently, This Analysis Has Been Limited To Relatively High Speed Vehicle Collisions, Where The Effects Of Restitution And Tire Forces Can Easily Be Neglected Without Effecting The Accuracy Of The Analysis. This Paper Focuses On The Analysis Of Motor Vehicle Damages Resulting From Minor Damage, Low Speed Impacts, Where Restitution And Tire Forces May Often Make A Considerable Contribution To The Total Severity Levels Of Such An Accident Event. Like Many Other Fields Of Science And Engineering, There Still Remain A Small Number Of Analysts Whom Have Either Failed To Keep Up With Modern Advances In Damage Analysis, Do Not Know How To Perform A Proper Damage Based Analysis Or Simply Do Not Recognize Its Usefulness And Accuracy. The Focus Of This Paper Is To Develop Damage Based Analysis Methods Applicable To Low Velocity Impacts And Demonstrate Their Usefulness To The Forensic Engineer.

Methods Of Reconstructing Motorcycle Collisions Have Traditionally Been Limited To Speed From Skid Marks, Speeds From Scrapes Or Gouges, Speed From Rider Ejection, Speed From Linear Momentum, Or Sometimes Speed From Witness Observations. Oftentimes, The Data Necessary For Analysis Is Either Misunderstood Or Misinterpreted. This Paper Tests The Applicability Of Using Rotational Mechanics And Specific Models For Motorcycle Front Fork Deformation And Vehicle Deformation When Determining Motorcycle Impact Velocity. Additionally, The Results Of These Methods Are Statistically Tested For Significance And Reliability Against Independent Motorcycle Impact Test Data.

Since the 1990s, domestic passenger vehicles have been equipped with increasingly more sophisticated supplemental restraint system event data recorders (EDRs) that have become more commonplace in collision analysis. Many collision analysts are aware that most heavy commercial vehicles are likewise equipped with heavy vehicle event data recorders (HVEDRs) that may trigger during a hard braking or sudden decelerationevent — or when the driver activates a signal to trigger an event to the system. Some heavy commercial vehicleengine manufacturers even provide an additional record of the last stop of the vehicle. Unfortunately, there areno uniform standards as to the information recorded or even the triggering criteria for an event regarding heavy commercial vehicles. HVEDR records oftentimes provide valuable information that assists the forensic engineer inanalyzing collision or failure events. This paper provides the forensic engineer with HVEDR engine manufacturer download coverage and tools needed (as of the presentation of this paper), and explores anomalies in event recording that the forensic engineer should be aware may exist. A case study pertaining to an HVEDR record of a commercial vehicle having a peculiar recording anomaly is presented. This paper outlines the process of how the anomaly was resolved and the process of plotting the sequence of events for courtroom presentation.

Analysis of vehicle deformation from impacts largely relies upon A and B stiffness coefficients for vehicle structures in order to approximate the velocity change and accelerations produced by an impact. While frontal impact stiffness factors for passenger vehicles, light trucks, vans, and sport utility vehicles are relatively prevalent for modern vehicles, stiffness factors for rear and side structures — as well as heavy vehicles, buses, recreational vehicles, trailers, motorcycles, and even objects — are essentially non-existent.

Analysis of vehicle deformation from impacts largely relies upon A and B stiffness coefficients for vehicle structures in order to approximate the velocity change and accelerations produced by an impact. While frontal impact stiffness factors for passenger vehicles, light trucks, vans, and sport utility vehicles are relatively prevalent for modern vehicles, stiffness factors for rear and side structures, as well as heavy vehicles, buses, recreational vehicles, trailers, motorcycles, and even objects, are essentially non-existent. This paper presents the application of the Generalized Deformation and Total Velocity Change Analysis to real-world collision events (G-DaTA?V™ System of Equations) as developed by this author. The focus of this paper addresses the relative precision and accuracy of the G-DaTA?V™ System of Equations for determining the total velocity change for oblique and/or offset vehicle-to-vehicle collisions involving light trucks and sport utility vehicles, which are largely under-represented with modern vehicle A and B stiffness values for side and rear surfaces. The previous paper presented by this author to the Academy addressed the relative accuracy and precision of the G-DaTA?V™ System of Equations as they relate to a first validation using the RICSAC-staged collision database. As a secondary and more comprehensive validation process, the G-DaTA?V™ System of Equations will be applied to real-world collision data obtained through the National Automotive Sampling System (NASS), which provides the National Highway Traffic Safety Administration (NHTSA) with a comprehensive compilation of real-world collision events representing a broad-based collection of collision configurations from across the country. This data represents a reusable source of information that was collected using standardized field techniques implemented by NASS-trained field technicians. Through using a “core set of crash data components,” NASS has demonstrated its utility and applicability to a vast array of statistical and analytical studies regarding traffic safety and vehicle collision dynamics.