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According to the Fatality Analysis Reporting System (FARS, 1995-2004), over 20 percent of fatal frontal crashes are into fixed narrow objects such as trees and utility poles in real world crashes. The Insurance Institute for Highway Safety (IIHS) has studied the frontal pole impact test since 2005, conducting a series of tests using passenger cars that are rated “Good” from the IIHS frontal offset test. Passenger cars were impacted into a 10-inch-diameter rigid pole at 64-kph. The alignment of the pole along the centerline of the vehicles in frontal impact was varied to study the influence on dummy injury metrics. This paper evaluates the frontal center pole test conducted by the IIHS. The IIHS tests 21 crashes impacted by the rigid pole using 5 vehicle models with two dummies in the front seat. Intrusions and dummy readings were reviewed according to the frontal offset rating criteria of the IIHS for structural performance and injury measurement.

The National Highway Traffic Safety Administration (NHTSA) conducted a total of 28 frontal crashes in the New Car Assessment Program (NCAP) involving the 10-year-old child Hybrid III dummy. The 10-year-old child dummy was in the rear seat. All types of vehicles (passenger cars, sport utility vehicles, vans and pick-up trucks) were tested to assess the effect of restraint systems such as booster and pretensioner on the rear seat occupant. In this study, the readings of the 10-year-old child dummy in rear-left and rear-right seat positions are examined. The authors apply a possible 5 star rating system, based on head and chest readings of the 10-year-old dummy. The paper also assesses the safety performance of rear seat occupants and the effect of the restraint systems on a child in the rear seat. This paper suggests that a star rating for rear seat occupants is independent of the present ratings for the driver and front adult passenger in NCAP.

The objective of this study was to analyze the position of the shoulder belt and adjustable upper anchorage (AUA) relative to the occupant in recent (2011-2012) NHTSA NCAP frontal crash tests. Since 2011, certain changes have been made in the NCAP test procedure. These changes include different Hybrid III occupant sizes as well as variations in the methods for calculating injury risk. One of the most significant changes has to do with thoracic injury risk calculation which was previously associated with chest acceleration and is now based on chest deflection as the measurable parameter. Using the NHTSA NCAP database, as well as other crash test data sources, a comparison was made between the designated upper anchorage position prior to a crash test and the actual position of the belt webbing with respect to the chest deflection measurement potentiometer sub-assembly of the Hybrid III.

According to National Highway Traffic Safety Administration (NHTSA) speed-related traffic fatalities accounted for 31% of total fatalities on U.S. roadways in 2003. Traditional speed control methods suffer from significant shortcomings. Adaptation (ISA) systems hold the promise of safer roadways through improving driver compliance with speed limits. This paper describes the development of a new multi-modal speed adaptation system to be tested in the CISR car-driving simulator. The system is capable of adapting to the driver's driving style and provides appropriate warning for over speeding based on the vehicle speed, speed limit, driver individual preferences, and risk factor. A hierarchical manager module determines the warning strategy. The adequate warning strategy is specific to driving situations and individual characteristics. Modes of warnings being considered include VISUAL, and HAPTIC.

This study focuses on the biaxial mechanical properties of planar aorta tissue at strain rates likely to be experienced during automotive crashes. It also examines the structural response of the whole aorta to longitudinal tension. Twenty-six tissue-level tests were conducted using twelve thoracic aortas harvested from human cadavers. Cruciate samples were excised from the ascending, peri-isthmic, and descending regions. The samples were subjected to equibiaxial stretch at two nominal speed levels using a new biaxial tissue-testing device. Inertia-compensated loads were measured to facilitate calculation of true stress. High-speed videography and regional correlation analysis were used to track ink dots marked on the center of each sample to obtain strain. In a series of component-level tests, the response of the intact thoracic aorta to longitudinal stretch was obtained using seven aorta specimens. The aorta fails within the peri-isthmic region.

This paper investigates the effects of driver airbag inflation characteristics, airbag relative position, airbag to dummy relative velocity, and steering column characteristics using a finite element model of a vehicle, air bag, and Hybrid III 50% male dummy. Simulation is conducted in a static test environment using a validated finite element model. Several static simulation tests are performed where the air bag module's position is mounted in a rigid steering wheel and the vertical and horizontal distances are varied relative to the dummy. Three vertical alignments are used: one position corresponds to the head centered on module, another position corresponds to the neck centered on module, and the third position centers the chest on the module. Horizontal alignments vary from 0 mm to 50 mm to 100 mm. All of these tests are simulated using a typical pre-1998 type inflation curve (mass flow rate of gas entering the bag).

Vehicle stiffness is one of the three major factors in vehicle to vehicle compatibility in a frontal crash; the other two factors are vehicle mass and frontal geometry. Vehicle to vehicle compatibility in turn is an increasingly important topic due to the rapid change in the size and characteristics of the automotive fleet, particularly the increase of the percentage of trucks and SUVs. Due to the non-linear nature of the mechanics of vehicle structure, frontal stiffness is not a properly defined metric. This research is aimed at developing a well defined method to quantify frontal stiffness for vehicle-to-vehicle crash compatibility. The method to be developed should predict crash outcome and controlling the defined metric should improve the crash outcome. The criterion that is used to judge the aggressivity of a vehicle in this method is the amount of deformation caused to the vulnerable vehicles when crashed with the subject vehicle.

This paper uses NASS/CDS 1997-2004 to determine the crash factors that are most frequently associated with rollover fires. Rollover fire cases were analyzed by the NASS variables including vehicle type, fire origin, number of quarter-turns, and final rest position. Results show that the engine compartment was the most frequent location for the fire origin. The fuel tank was second in this category. The rest position on the roof was most frequently associated with fires in rollovers. However, the fire rate was not strongly influenced by the final rest position. High severity rollovers that involve more than eight quarter-turns or end-over-end motion had fire rates much higher than the average. An examination of 24 cases with major fires in recent model year vehicles found that impacts prior to the rollover occurred in more than half of the cases. All of the cases with leakage from the fuel tank had impacts prior to the rollover.

This study assessed the primary involved physical components attributed to the head and face injuries of child occupants seated directly adjacent to the stuck side of a vehicle in a side impact collision. The findings presented in this study were based upon analysis of the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) for the years 1993–2007. Injury analysis was conducted for those nearside child occupants aged between 1–12 years-old. The involved children were classified as toddler-type, booster-type, or belted-type occupants. These classifications were based upon the recommended restraint system for the occupant. Injury mechanisms were assessed for the child occupants in each of the three groups. A detailed study of NASS/CDS cases was conducted to provide a greater understanding of the associated injury mechanisms.

This paper investigates the crashworthiness of structural composite components in frontal and side crash tests. In addition, the safety benefits of composites applications in future lighter vehicles are studied. The methodology of the research includes two steps: (1) developing a light-weight vehicle based on a current finite element (FE) vehicle using advanced plastics and composites, and (2) evaluating the crashworthiness of the light-weighted vehicle by frontal and side New Car Assessment Program (NCAP) test simulations. An FE model of a 2007 Chevrolet Silverado, which is a body-on-frame pickup truck, was selected as the baseline vehicle for light-weighting. By light-weighting components in the Silverado, the vehicle weight was reduced 19%. As a result, the content of plastics and composite in the light-weighted vehicle was 23.6% of the total weight of the light-weight vehicle.

This study investigated the mechanisms of traumatic rupture of the aorta (TRA). Eight unembalmed human cadavers were tested using various dynamic blunt loading modes. Impacts were conducted using a 32-kg impactor with a 152-mm face, and high-speed seatbelt pretensioners. High-speed biplane x-ray was used to visualize aortic motion within the mediastinum, and to measure deformation of the aorta. An axillary thoracotomy approach was used to access the peri-isthmic region to place radiopaque markers on the aorta. The cadavers were inverted for testing. Clinically relevant TRA was observed in seven of the tests. Peak average longitudinal Lagrange strain was 0.644, with the average peak for all tests being 0.208 ± 0.216. Peak intraluminal pressure of 165 kPa was recorded. Longitudinal stretch of the aorta was found to be a principal component of injury causation. Stretch of the aorta was generated by thoracic deformation, which is required for injury to occur.

This paper creates a worksheet to thoroughly document vehicle damage during an incompatible vehicle-to-vehicle frontal crash. This data form serves as a supplement to the current and already established NASS inspection forms. It will assist biomechanics research by determining the extent by which incompatibility caused or changed occupants' injuries through structural analysis of the vehicles. This study identifies deficiencies in the current NASS inspection system for compatibility, and develops new measurable parameters to document the crash and associate injury to it.

This paper presents an analysis of the National Automotive Sampling System (NASS) and the Fatal Accident Reporting Systems (FARS) data for the combined years 1988–97 with respect to side impacts. Accident variables, vehicle variables, occupant variables and their interactions have been considered, with special emphasis on occupant injury patterns. The crash modes considered are car-to-car, car-to-LTV (light trucks and vans) and car to narrow object, with special emphasis on the latter two. This study was undertaken to obtain a better understanding of injury patterns in lateral impacts, their associated causation factors, and to obtain information that will assist in prioritizing crash injury research problems in near side impacts. Of particular interest is the increase in the population of light trucks and vans and their influence on side impact priorities. Conclusions will be drawn regarding the frequency and injury severity of car-to-LTV’s and car to narrow objects.

In this study, the level of protection offered to rear seat occupants in frontal crashes is investigated. The Fatality Analysis Reporting System (FARS) and National Automotive Sampling System Crashworthiness Data System (NASS CDS) databases were used for the analyses. The investigation focused on: 1- estimating the fatality protection effectiveness of the rear seat position relative to the right front seat position, using the double paired comparison method, 2- evaluating the effect of control group selection method on effectiveness predictions, and 3- identifying trends in rear seat occupant protection over model years of vehicles. By applying a uniform control group to the double paired comparison analysis of FARS data, this study suggests that all ages of occupants are safer in the rear seat than in the right front seat. Effectiveness estimates ranged from 5.9% to 82% for different age groups of occupants.

Traumatic rupture of the aorta (TRA) is an important transportation-related injury. This study investigated TRA mechanisms using in situ human cadaver experiments. Four quasi-static tests and one dynamic test were performed. The quasi-static experiments were conducted by perturbing the mediastinal structures of the cadavers. The mechanisms investigated included anterior, superior, and lateral displacement of the heart and aortic arch. The resulting injuries ranged from partial tears to complete transections. All injuries occurred within the peri-isthmic region. Intimal tears were associated with the primary injuries. The average failure load and stretch were 148 N and 30 percent for the quasi-static tests. This study illustrates that TRA can result from appropriate application of nominal levels of longitudinal load and tension. The results demonstrate that intraluminal pressure and whole-body acceleration are not required for TRA to occur.