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During the period 1992 through 2000, the William Lehman Injury Research Center collected crash and injury data on 141 drivers and 41 right front passengers in frontal crashes with air bag deployment. Among these cases were twenty-eight cases with depowered air bags. The paper compares the crash characteristics for injured occupants in vehicles with 1st generation and depowered air bags. The population with 1st generation air bags contains unexpected fatalities among as well as fatalities at low delta-V's. To date, these populations are absent among the fatally injured occupants of vehicles with depowered air bags. The depowered cases include both belted and unbelted survivors at crash severities above 40 mph delta-V. The maximum injury in these severe crashes was AIS 3 with no evidence of unsatisfactory air bag performance. However, serious internal chest injuries were observed in two cases with unrestrained drivers at crash severities of 19 and 24 mph.

In this study, the comparative stiffness of vehicle side and frontal structures is determined by available static test and crash test data. NHTSA has conducted a series of staged crash tests where a Honda Accord is impacted by different bullet vehicles at a closing velocity of 32.5 mph. These staged front-to-side crash tests are examined to assess the extent of damage to both the bullet and struck vehicle. The load cell barrier data for the bullet vehicles used in NHTSA's vehicle-to-vehicle front-to-side crash tests are examined to determine the geometric and stiffness properties of the frontal structures as measured in the NCAP tests. The geometric and stiffness measurements during the early stages of frontal crush are most influential in front-to-side crashes. The barrier data provides useful stiffness information. However, the number of rows of load cells may be insufficient to provide geometric information.

The National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the barrier in crash tests. Thirty-six load cells on the face of the rigid barrier measure the force. This study examines the load cell barrier data collected during recent years of NCAP testing to determine how it can be used to assess vehicle compatibility in vehicle-to-vehicle front-to-side crashes. The height of the center-of-force measured by the columns of load cells is proposed as a metric for quantitatively describing the geometric properties of the crash forces. For front-to-side crashes, the geometric and stiffness properties of frontal structures during the early stages of crush are applicable. Consequently, geometric and stiffness measurements at a crush of 125 mm are presented in this paper. This paper shows the range of the compatibility and stiffness parameters measured on cars, pickups, vans, and multi-purpose vehicles.

In the United States, the National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the rigid barrier in frontal crash tests. Thirty-six load cells on the barrier face measure the distribution of the crash forces. This study examined the load cell barrier data collected during recent years to assess the geometric distribution of the crash forces and the variation in stiffness across the vehicle width. The location of the Center of Force was proposed as a metric for quantitatively describing the geometric properties of the crash forces. The Center of Force location was calculated for each column of load cells. Variations in the Center of Force location across the width of the barrier were examined for typical vehicles. This study applies the aggressiveness metric to a frontal crash from NASS/CDS 1997 in which a passenger car collided with a light truck.

The National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the barrier in crash tests. Thirty-six load cells on the face of the rigid barrier measure the force. This study examines the load cell barrier data collected during recent years of NCAP testing to determine how it can be used to assess vehicle structural crash characteristics and vehicle compatibility in car to car crashes. Several aggressiveness metrics are proposed for different crash modes. The proposed metrics for frontal crash modes are the stiffness and the height of the center of force at 375 mm of crush, in addition to the vehicle mass. For front-to-side vehicle crashes, some additional metrics are required. The force distribution when the loading is sufficient to cause intrusion of the side door is proposed as the basis for a metric. A high percentage of force on the lowest rows of load cells is indicative of front-to-side loading, which should be desirable.

This paper examines injuries and injury mechanisms in side impact crashes being addressed by the United States standard, FMVSS 214. In this side impact protection standard, a moving deformable barrier impacts the occupant compartment of a vehicle being tested. The moving barrier is crabbed at an angle of 23 degrees measured relative to the side of the struck vehicle. The standard assesses the crash protection provided in a vehicle-to-vehicle crash to an occupant seated on the struck side, in the vicinity of the maximum intrusion. The National Automobile Sampling System /Crashworthiness Database System (NASS/CDS) data indicates that 75% AIS 3+ injuries occur in vehicle-to-vehicle crashes, 66% occur to the struck side occupants and 94% occur in crashes with damage to the occupant compartment. Crash directions of 10 and 2 o’clock are the most common injury producing crashes.

The University of Miami's William Lehman Injury Research Center at the Jackson Memorial Medical Center conducts interdisciplinary investigations to study seriously injured restrained occupants in frontal automobile collisions. Engineering analysis of these crashes is conducted in conjunction with the National Crash Analysis Center at the George Washington University. The multi-disciplinary research team includes expertise in crash investigation, crash reconstruction, computer graphics, biomechanics of injuries, crash data analysis, emergency trauma care, and all of the medical specialties associated with the Ryder Trauma Center at Jackson Memorial Hospital. More than 300 injured occupants and their crashes have been studied in depth. By careful study of injured crash victims, their vehicle and the crash scene, injury patterns emerge. These patterns form the basis for hypotheses which can be explored further by analysis of mass accident data, crash tests, and computer modeling.

The National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the barrier in crash tests. Thirty-six load cells on the face of the rigid barrier measure the force. This study examines the load cell barrier data collected during recent years of NCAP testing to determine how it can be used to assess vehicle structural crash characteristics and vehicle compatibility in car to car crashes. To illustrate the value of the data, the load cell measurements for an SUV are compared with a small car. Several aggressiveness metrics are proposed for different crash modes. The proposed metrics for frontal crash modes are the force at 250 mm of crush, the linear stiffness at various levels of crush, and the height of the center of force at 250 mm of crush. For front-to-side vehicle crashes, some additional metrics are proposed. The force distribution when the loading is sufficient to cause intrusion of the side door is proposed as the basis for a metric.