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The aim of the study was to investigate the difference between car-to-e-bikes and car-to-pedestrian accidents. The China In-depth Accident Study (CIDAS) database was searched from 2011 to 2013 for pedestrians and e-bikes struck by car, van and SUV fronts, which resulted in 104 pedestrian and 85 e-bike cases where information was sufficient for in-depth analysis. Reconstruction by PC-Crash was performed for all of the sampled cases. Pre-crash parameters were calculated by a MATLAB code. Focus was on prototypical accident scenarios and causes; speed as well as possible prevention countermeasures. It has been shown that traffic light violations, road priority violations, and unsure safety (these situations included misjudgments, unpreparedness, proximity to other road users, inappropriate speeds, etc.…) are the main causes in both the VRU groups. Distinctions were found for aspects of car collision speed, accident scenario, distribution of head contact points and so on.

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.

Rear seat adult occupant protection is receiving increased attention from the automotive safety community. Recent anthropomorphic test device (ATD) studies have suggested that it may be possible to improve kinematics and reduce injuries to rear seat occupants in frontal collisions by incorporating shoulder-belt force-limiting and pretensioning (FL+PT) technologies into rear seat 3-point belt restraints. This study seeks to further investigate the feasibility and potential kinematic benefits of a FL+PT rear seat, 3-point belt restraint system in a series of 48 kmh frontal impact sled tests (20 g, 80 ms sled acceleration pulse) performed with post mortem human surrogates (PMHS). Three PMHS were tested with a 3-point belt restraint with a progressive (two-stage) force limiting and pretensioning retractor in a sled buck representing the rear seat occupant environment of a 2004 mid-sized sedan.

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.

To date, efforts to improve occupant protection in side impact crashes have concentrated on reducing the injuries to occupants seated on the struck side of the vehicle arising from contact with the intruding side structure and/or external objects. Crash investigations indicate that occupants on the struck side of a vehicle may also be injured by contact with an adjacent occupant in the same seating row. Anecdotal information suggests that the injury consequences of occupant-to-occupant impacts can be severe, and sometimes life threatening. Occupant-to-occupant impacts leave little evidence in the vehicle, and hence these impacts can be difficult for crash investigators to detect and may be underreported. The objective of this study was to evaluate the risk of impact injury from occupant-to-occupant impacts in side impact vehicle crashes. The study examined 9608 crashes extracted from NASS/CDS 1993-2006 to investigate the risk of occupant-to-occupant impacts.

In this paper the characteristics of rear impact crashes are examined. General information about rear impact collisions is derived from recent data from the National Automotive Sampling System, General Estimates System (NASS/GES) and Fatality Analysis Reporting System (FARS) as reported in the annual National Highway Traffic Safety Administration (NHTSA) Traffic Safety Facts. Additional details about the frequency, severity, type, and cause of injuries to front seat outboard occupants is analyzed using the National Automotive Sampling System, Crashworthiness Data System (NASS/CDS) data from 1997 to 2005. Serious head and neck injuries are focused on for further analysis. Specific cases from the CDS database that meet this classification are examined. Federal Motor Vehicle Safety Standard (FMVSS) 301-R test data is used to analyze occupant, seat, and vehicle kinematics in single impact rear collisions and to look at the occupant rebound velocity.

Injury to the far side occupant has been demonstrated as a significant portion of the total trauma in side impacts. The objective of the study was to determine the response of PMHS in far side impact configurations, with and without generic countermeasures, and compare responses to the WorldSID and THOR dummies. A far side impact buck was designed for a sled test system that included a center console and three-point belt system. The buck allowed for additional options of generic countermeasures including shoulder or thorax plates or an inboard shoulder belt. The entire buck could be mounted on the sled in either a 90-degree (3-o'clock PDOF) or a 60-degree (2-o'clock PDOF) orientation. A total of 18 tests on six PMHS were done to characterize the far side impact environment at both low (11 km/h) and high (30 km/h) velocities. WorldSID and THOR-NT tests were completed in the same configurations to conduct matched-pair comparisons.

Injury to the far side occupant has been demonstrated as a significant portion of the total trauma in side impacts. The objective of the study was to determine the response of PMHS in far side impact configurations, with and without generic countermeasures, and compare responses to the WorldSID and THOR dummies. A far side impact buck was designed for a sled test system that included a center console and three-point belt system. The buck allowed for additional options of generic countermeasures including shoulder or thorax plates or an inboard shoulder belt. The entire buck could be mounted on the sled in either a 90-degree (3-o'clock PDOF) or a 60-degree (2-o'clock PDOF) orientation. A total of 18 tests on six PMHS were done to characterize the far side impact environment at both low (11 km/h) and high (30 km/h) velocities. WorldSID and THOR-NT tests were completed in the same configurations to conduct matched-pair comparisons.

EuroNCAP and regulations in Europe and Japan evaluate the pedestrian protection performance of cars. The test methods are similar and they all have requirements for the passive protection of the hood area at a pedestrian to car impact speed of 40 km/h. In Europe, a proposal for a second phase of the regulation mandates a brake-assist system along with passive requirements. The system assists the driver in optimizing the braking performance during panic braking, resulting in activation only when the driver brakes sufficiently. In a European study this was estimated to occur in about 50% of pedestrian accidents. A future system for brake assistance will likely include automatic braking, in response to a pre-crash sensor, to avoid or mitigate injuries of vulnerable road users. An important question is whether these systems will provide sufficient protection, or if a parallel, passive pedestrian protection system will be necessary.

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.

The literature contains a wide range of response data describing the biomechanics of isolated body regions. Current data for the validation of frontal anthropomorphic test devices and human body computational models lack, however, a detailed description of the whole-body response to loading with contemporary restraints in automobile crashes.

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 2003, 2004, 2005]. This paper summarizes progress in several of the projects dealing with underhood fires and testing of a hydrogen fuel tank. Calorimeter tests of underhood materials found a wide range of flammability for the structural plastics as well as the underhood sound insulation. Calorimeter tests of underhood fluids (lubricants and hydraulic fluid) showed that their flash points were less than 188°C and the minimum temperature of a hot surface to cause ignition was less than 325°C. Tests of four different vehicles to determine the exhaust manifold operating temperatures found a range between 241°C and 550°C.

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.

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.

The major car and crash related risk factors for Whiplash Associated Disorders (WAD) 1-3 long-term neck injuries in rear-end crashes are the shape of the crash pulse, the seat-force characteristics and the head restraint position. However, the specific roles of these factors are not yet fully understood, which makes it difficult to find adequate countermeasures and to design protective car seats. In order to study these issues, a mathematical MADYMO model of the first version of the Biofidelic Rear Impact Dummy (BioRID I) has previously been developed. In addition, a neck injury criterion, NICmax, has been proposed and evaluated by means of dummy, human and rear-end impact simulations. In this paper the MADYMO BioRID I and four car seats ranked differently according to a disability ranking list are used to study the influence of crash pulse, seat-force characteristics, and head restraint position on the NICmax in rear-end crashes.

This paper examines the crash involvement and occupant safety record of sport utility vehicles (SUV’s) in comparison with those of cars, vans, and pickups. The investigation is based on the crash experience of the cited vehicles on the US roads, from 1988 to 1996, as compiled in the National Highway Traffic Safety Administration’s (NHTSA’s) records. In comparison with passenger car occupants, SUV occupants are exposed to significantly lower crash severities in planar crashes and they are younger. SUV occupants are underrepresented in crashes with other vehicles, but they are more frequently exposed to rollovers (8.7% vs. 33%). The overall belt use rate in SUV’s is about the same as for passenger cars. The overall belt use rate in rollover crashes is much lower than in planar crashes -51% for rollover vs. 62% for planar.

Automobile insurance claims of two popular midsize cars with different air bag deployment frequencies -- the Dodge/Plymouth Neon and Honda Civic -- were examined to determine performance in higher severity crashes (the upper 30 percent of crashes ranked by adjusted repair cost). Previously, it was found that drivers sustained more, mainly minor, injuries in the Neon which had a higher deployment frequency in low speed crashes. This study examined, for these two cars, whether there was any trade-off associated with a higher deployment threshold. It was found that even at higher speeds, the Neon had a greater frequency of air bag deployments, which in turn resulted in a greater likelihood of driver injury. Once again upper extremity injuries were most prevalent for Neon drivers and were highest for female drivers. At the same time, there was little evidence that driver protection was compromised in the Civic in the more important high speed crashes.

The William Lehman Injury Research Center has conducted multi-disciplinary investigations of fifty crashes involving drivers protected by air bags. In all cases, serious injuries were suspected. Nine cases involved fatal injuries. These cases are not representative of crashes in general. However, when used in conjunction with NASS/CDS they provide insight into the most severe injuries in crashes of vehicles equipped with air bags. A comparison with data from the National Accident Sampling System; Crashworthiness Data System (NASS/CDS) shows that head injury and abdominal injury make up a larger fraction in the Lehman data than in NASS/CDS. Examination of fatal cases indicates that head injuries are frequently caused by intruding structure or by unfavorable occupant kinematics among the unrestrained population.