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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 investigation was to understand relationships among loading characteristics as they affect the kinematics and injury of a pedestrian’s lower extremity. Real-life pedestrian and motor vehicle collision scenarios were modeled by impacting 604 human cadaver intact legs and long bones with a cart/guide rail impacting system designed to simulate the front end of an automobile. A parametric study was conducted that varied the boundary conditions on the foot as well as test parameters such as loading direction, impact velocity, and impactor geometry. The series of tests can be categorized as follows: (1) Fracture Characterization, (2) Threshold Velocity, (3) Friction versus Inertial Constraint, (4) Anterior and Lateral Thigh Impacts, and (5) Embalmed vs. Unembalmed. Documented data for various specimens include, but are not limited to, specimen anthropometrics, fracture patterns, failure force levels, and calculated bending moments.

This paper examines an originally designed airbag deployment system for use in static experimental testing. It consists of a pressure vessel and valve arrangement with pneumatic and electric controls. A piston functions like a valve when operated and is activated pneumatically to release the air in the tank. Once released, the air fills the attached airbag. The leading edge velocity can be controlled by the initial pressure in the tank, which can range up to 960 kPa. Three different test configurations were studied, which resulted in leading edge deployment speeds of approximately 20 m/s, 40 m/s, and 60 m/s. In experiments using this system, seven types of airbags were tested that differed in their material, coating, and presence of a tether. Data for each series of tests is provided. High speed video and film were used to record the deployments, and a pressure transducer measured the airbag's internal pressure.

The air bag system is described in terms of four basic elements: the crash sensors and controls, the inflator, the air bag itself, and the diagnostic circuitry. A general discussion of these elements is provided and a review of air bag related injuries is also presented which includes data from various sources such as the University of Michigan Transportation Research Institute, National Highway Traffic and Safety Administration, Transport Canada, and the Insurance Institute for Highway Safety. The most frequently occurring accident type is the frontal collision and has been the main focus of safety efforts with regard to restraint systems. Air bags are an effective injur/prevention device, however their deployment can introduce new injury mechanisms. Air bags save lives and decrease the severity of major injuries in exchange for increasing the number of minor injuries.

It has been widely reported that injury to the leg is the most common form of non-fatal trauma associated with motorcycle accidents. Furthermore, it has also been reported that the majority of motorcycle leg injuries resemble those experienced by pedestrians in that they do not involve crush. Rather, these injuries appear to involve only a direct impact between the leg and an opposing rigid object. Often the soft tissue of the limb is injured from the inside out in that sharp bone fragments and jagged ends lacerate the soft tissue as relative motion occurs. The complexity of understanding these results is due to a combination of impact effects, biological material properties and human geometric considerations. Our ongoing research, underway for several years, is providing the fundamental data for cadaver leg and bone impact response.