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The use of the United States’ Global Positioning System (GPS) to assist with the management of large commercial fleets using telematics is becoming commonplace. Telematics generally refers to the use of wireless devices to transmit data in real time back to an organization. When tied to the GPS system telematics can be used to track fleet vehicle movements, and other parameters. GPS tracking can assist in developing more efficient and safe operations by refining and streamlining routing and operations. GPS based fleet telematics data is also useful for reducing unnecessary engine idle times and minimizing fuel consumption. Driver performance and policy adherence can be monitored, for example by transmitting data regarding seatbelt usage when there is vehicle movement. Despite the advantages for fleet management, there are limitations in the logged data for position and speed that may affect the utility of the system for analysis and reconstruction of traffic collisions. The U.S.

Traditional accident reconstruction analysis methodologies include the study of the crush-energy relationship of vehicles. By analyzing the measured crush from a vehicle involved in a real world accident and comparing it to a test vehicle with a known energy, from a crash test, the real world vehicle's damage energy can be evaluated. In addition, the change-in-velocity (Delta-V) can be calculated. The largest source of publicly available crash tests is from the National Highway Traffic Safety Administration (NHTSA). NHTSA conducts numerous Federal Motor Vehicle Safety Standard (FMVSS) compliance and New Car Assessment Program (NCAP) testing for many passenger vehicles for sale in the United States.

This paper presents a methodology to determine the approximate closing speed of a striking vehicle and resultant delta-v of the struck vehicle in low speed collinear rear impacts through analysis of the paint damage pattern evident on the struck vehicle's rear bumper. This methodology is only applicable to collisions between vehicles that possess painted flexible plastic foam supported bumpers. Five impacts at each of 1.12 m/s, 1.79 m/s, and 2.69 m/s target speeds and three impacts at 3.58 m/s target speeds were conducted to provide the foundation for this methodology. The use of powdered guidecoat is introduced to contrast the damage pattern on the bumper of the struck vehicle. A measurement of contact paint damage area is obtained and that damage area is then correlated to a closing velocity between the two vehicles. Measured coefficients of restitution and calculated quantities of energy absorbed are also presented for each impact.

This study focused on the role of PhotoModeler, a close-range photogrammetry software package, in an important facet of traffic accident reconstruction—vehicle crush measurement. More specifically, this study applied the PhotoModeler process to controlled crash information generated by the National Highway Traffic Safety Administration (NHTSA). A statistical technique known as bootstrapping was utilized to generate distributions from which the variability was examined. The “within” subject analysis showed that 44.8% of the variability is due to the technique itself and the “between” subjects analysis demonstrated that 55.2% of the variability is attributable to vehicle type—roughly half and half. Additionally, a 95% CI for the “within” analysis revealed that the mean difference (between this study and NHTSA) fell between −2.52 mph and +2.73 mph; the “between” analysis showed a mean difference between −3.26 mph and +2.41 mph.

The objective of this study was to examine the effectiveness of the typical 3-point restraint system during a quarter-turn rollover of a heavy truck. Five far-side, quarter-turn rollover dynamic tests (3 belted and 2 unbelted tests using a Hybrid II dummy) were conducted using a specially designed large hydraulic machine (causing typical real-world peak angular velocities such as 115° to 140° per second). Four far-side, quarter-turn+ (∼110°) static rollover tests (all belted - one test with a Hybrid II test dummy and the other three with human volunteers) were conducted using a specially designed machine driven by rotational motion from an electric motor (constant roll speed of approximately 6° to 7° per second). A tractor cab and seat and the most commonly used dual-sensitive 3-point belt system were mounted on the test machines. Instrumentation included various transducers, accelerometers, and high speed video cameras to record selected data.