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Far-side occupants are not addressed in current government regulations around the world even though they account for up to 40% of occupant HARM in side impact crashes. Consequently, there are very few crash tests with far-side dummies available to researchers. Sled tests are frequently used to replicate the dynamic conditions of a full-scale crash test in a controlled setting. However, in far-side crashes the complexity of the occupant kinematics is increased by the longer duration of the motion and by the increased rotation of the vehicle. The successful duplication of occupant motion in these crashes confirms that a sled test is an effective, cost-efficient means of testing and developing far-side occupant restraints or injury countermeasures.

This investigation addresses and evaluates: (1) belted drivers in frontal crashes; (2) crashes divided into low, medium, and high severity; (3) air-bag-equipped passenger vehicles separated into either model years 1985 - 1997 (with airbags) or model years 1998 - 2008; (4) rate of Harm as a function of crash severity and vehicle model year; and (5) injury patterns associated with injured body regions and the involved physical components, by vehicle model year. Comparisons are made between the injury patterns related to drivers seated in vehicles manufactured before 1998 and those manufactured 1998 or later. The purpose of this comparative analysis is to establish how driver injury patterns may have changed as a result of the introduction of more recent safety belt technology, advanced airbags, or structural changes.

The basis for this analysis was NASS/CDS 1997 to 2006. In the NASS database there were 60 cases with major fires in side impact crashes, 37 of which were in passenger vehicles less than 10 years old. These newer vehicles were examined in this study. Cases in NASS were examined to identify crash characteristics associated with major fires in side crashes. The database contained 22 cases with fatalities, eleven of which were coded as fire related. Three of these were associated with fires that did not originate from the crashed vehicle. The fuel tank was coded as the fire origin for 41% of the major fires in vehicles with side damage and for 7 out of the 8 vehicles with fire related fatalities. The most frequent crash characteristic was an impact with a narrow object that produced severe side damage. Lower extent of damage was evident in two fatal cases that involved a rollover following the side impact.

The basis for this analysis was FARS 1979 to 2005 and NASS/CDS 1997 to 2004. For these years, there were 12,493 cases in FARS where fire was coded as the most harmful event. In NASS there were 227 cases with major fires, 87 of which were in frontal crashes. The paper shows the annual trends in FARS with regard to overall fatalities and fatalities with fire as the most harmful event by direction of principal vehicle damage. The NASS/CDS files are used to determine the location of fire origin. The FARS data show that crashes with frontal damage are the most frequent crash types where fire is the most harmful event. In general, the most harmful event fire rates have declined with the overall fatality rates in FARS. However, in recent years the trend in fires with frontal damage has been on the increase. Cases in NASS were examined to identify patterns for major fires in frontal crashes. Engine compartment fires were by far the most frequent.

The National Highway Traffic Safety Administration (NHTSA) Special Crash Investigations database contains twelve completed cases of child fatalities in rearward facing child seats caused by deploying air bags. Three of these are now available for examination. An additional two cases were investigated by the William Lehman Injury Research Center at the University of Miami School of Medicine. These five cases are examined to evaluate crash environment, injury mechanisms, and circumstances which caused the child to be in front of the passenger side air bag Four of the cases were crashes with impacts with the side of other cars with crash severities less than 15 mph. The predominate injury mechanism was brain and skull injury from a blow transmitted to the rear of the head through the child seat back. In one case, the force to the head was transmitted downward, directly from air bag contact.

To date, anthropomorphic test devices (ATDs) have not been designed with consideration for human motion in far-side impacts. Previous tests with a cadaver and a BioSID dummy at the Medical College of Wisconsin confirmed that the dummy does not suitably model the human motion. To further evaluate different ATDs in far-side crashes, MAthematical DYnamic MOdeling (MADYMO) was employed. The modeling showed that the motion of a Hybrid III, BioSID, EuroSid1, EuroSID2, or SID2s did not accurately reflect the motion of a human cadaver under the same impact configurations as the cadaver test. The MADYMO human facet model was found to closely reproduce the kinematics of the cadaver test. The effect of varying console designs on occupant kinematics is presented in this paper. The human facet model appears to be a good interim tool for the evaluation of countermeasures in far-side crashes.

A common injury type among foot and ankle injury is the Lisfranc trauma, or injury to the forefoot. The Lisfranc injury indicates abnormal alignment of the tarsal-metatarsal joints with the loss of their normal spatial relationships. In 2003, Smith completed a laboratory study of this injury mechanism at Wayne State University [1, 2]. He found Lisfranc trauma was correlated with impact force to the forefoot. He proposed a probability of injury function that is based on the applied force to the forefoot. This study examined the instrumentation in the foot of the dummies in the USA New Car Assessment Program (NCAP) and Insurance Institute of Highway Safety (IIHS) frontal crashes. Nineteen different passenger vehicles representing four different vehicle classes were selected based mostly on a large presence in the USA vehicle fleet. Both NCAP and IIHS crashed these nineteen makes and models.

The research reported in this paper is a follow-on to a five year research program conducted by General Motors in accordance with an administrative Settlement Agreement reached with the US Department of Transportation. This paper is the fourth in a series of technical papers intended to disseminate the results of the ongoing research [Digges 2004, 2005, 2006]. This paper summarizes progress in several of the projects to better understand the crash factors that are associated with crash induced fires. Part I of the paper presents the distribution of fire cases in NASS/CDS by damage severity and injury severity. It also examines the distributions by crash mode, fire origin, and fuel leakage location. The distributions of cases with fires and entrapment are also examined. Part II of the paper provides summaries of recent projects performed by MVFRI contractors. Technologies to reduce fuel leakage from siphoning and rollover are documented.

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.

Rollover crashes continue to be a serious and growing vehicle safety problem. Rollovers account for about 9% of passenger car crashes, and 26% of light truck crashes. Belt use in rollover crashes is about 51%, compared with 62% in planar crashes. Overall, 26.4% of the serious and fatal injuries to occupants exposed to crashes are in rollovers. Among this injured population 74.4% are unbelted. In light trucks, rollovers account for 47.4% of the serious or fatal injuries. Unbelted occupants suffer about 87% of the serious injuries and fatalities in light truck rollovers. The use of safety belts offers a dramatic reduction in injury rates for rollover crashes. For belted occupants of pickup trucks and utility vehicles in rollover crashes, the injury rates are about the same as for belted occupants of passenger cars in planar crashes. Improvementsts in safety belts offer large opportunities in safety.

The purpose of this paper is to assess the vehicle environment that a child occupant, between the ages of seven and thirteen years old, is exposed to in a real world crash. The focus of analysis is on those child occupants that are seated at the struck side in a lateral collision. This study was based on data extracted from the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) between years 1991-2006. Analysis was based upon the evaluation of the projected consequence of injury to the child occupants. The societal costs generated as a result of occupant injuries were quantified. The societal cost, or Harm, acts as a measure of consequence of occupant exposure to the vehicle environment, when involved in a collision. The Harm was determined as a function of ΔV, principal direction of force, vehicle extent of damage, the pattern of damage to the vehicle, and the magnitude of intrusion based on the occupant seating position.

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 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.

The research reported in this paper is a follow-on to a five year research program conducted by General Motors in accordance with an administrative Settlement Agreement reached with the US Department of Transportation. In a subsequent Judicial Settlement, GM agreed fund more than $4.1 million in fire related research over the period 2001-2004. The purpose of this paper is to provide a public update report on the projects that have been funded under this latter research program, along with results to date. An analysis of FARS and State accident data has been completed. Results indicate that fire rates have been significantly reduced over the past 20 years. Fire rates for passenger cars and LTVs have approached similar levels. Fire rates by crash mode indicate that rear impact fires have been significantly reduced; however, fires in rollover crashes have seen considerably less reduction. The highest percentages of fires are subsequent to frontal impacts.

Real world crashes in NASS/CDS 1997 to 2000 were examined individually in order to find patterns in single vehicle rollover crashes. Typical maneuver induced rollovers of SUV's were reconstructed using the HVE model. From HVE and roll event reconstructions, the values of longitudinal, lateral, and vertical displacement, and roll, pitch, and yaw angle, for the pre-roll and rollover event were calculated. These values were used as inputs to a MADYMO model for simulated vehicle motion to predict occupant kinematics. Both near-side and far-side rollovers were simulated. The MADYMO model provided estimates of head velocity for the various rollover scenarios for a belted driver. In both near-side and far-side rollovers of the type reconstructed, the lateral component of head velocity was the greatest. Maximum head velocities of 5.3 m/s were predicted. The simulations were for two complete rollovers. The highest head velocity occurred during the first three quarter turns.

The U.S. Department of Transportation-sponsored Crash Injury Research and Engineering Network (CIREN) program offers a reasonable look at the efficacy of second-generation air bags. This paper examines the data from the William Lehman Injury Research Center (WLIRC). The WLIRC data is a near census of crashes in the Miami-Dade region with occupants that appear to be severely injured. The percentage of deaths among trauma patients in the WLIRC data as a function of delta-V for first-generation air bags was higher than expected at lower delta-V's. There were nine driver fatalities at delta-V's of less than 20 mph (four involving short stature occupants, four with elderly occupants, and one due to significant intrusion and/or vehicle incompatibility). The data supported NHTSA's conclusion that first-generation air bags were too aggressive for occupants in close proximity to the deploying air bag and too aggressive for older persons.

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 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.

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.

The research question investigated in this study is what are the key attributes of foot and ankle injury in the between-rail frontal crash? For the foot and ankle, what was the type of interior surface contacted and the type of resulting trauma? The method was to study with in-depth case reviews of NASS-CDS cases where a driver suffered an AIS=2 foot or ankle injury in between-rail crashes. Cases were limited to belted occupants in vehicles equipped with air bags. The reviews concentrated on coded and non-coded data, identifying especially those factors contributing to the injuries of the driver's foot/ankle. This study examines real-world crash data between the years 1997-2009 with a focus on frontal crashes involving 1997 and later model year vehicles. The raw data count for between-rail crashes was 732, corresponding to 227,305 weighted, tow-away crashes.