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To minimize injury to the occupants, the frontal vehicle structure must absorb much more energy in the first deformation phase in case of a high-speed collision. Depending on the crash situation, an intelligent system must regulate the structure stiffness yielding additional energy absorption by means of friction. Concept ideas are mentioned to achieve different crash pulses at different crash velocities within the available deformation length. An independent search for optimal deceleration pulses at several crash velocities is necessary, because the usually found structure-based pulses are not obviously the optimal pulses for minimal injury to the occupants. Therefore, in this paper the more interesting case of the reverse question is answered: which crash pulse gives the lowest injury levels with an already optimized restraint system, instead of finding the optimized restraint system for a given crash pulse.

The Thor-Lx leg and foot complex is being developed by the National Highway Traffic Safety Administration (NHTSA), the Applied Safety Technologies Corporation, and GESAC, Inc., as a new research and development (R&D) tool which will be more biofidelic than the current Hybrid-III lower extremity. This paper reviews the results from a matrix of tests performed to evaluate the response of the Thor-Lx in comparison to the Hybrid-III lower extremity in high-speed frontal crashes. The testing included three 64 km/h frontal offset deformable barrier tests and two 56 km/h flat rigid barrier tests. Testing was done using the following Anthropomorphic Test Device (ATD) combinations: Hybrid-III with the Hybrid-III Enhanced Instrumented Tibia, Hybrid-III with the Thor-Lx, and Thor with the Thor-Lx. The response of the lower extremity was found to vary with each leg and torso combination.

An analysis of the National Automotive Sampling System/ Crashworthiness Data System (NASS/CDS) for the years 1993–1999 was conducted to determine the risk of injury to different body regions in frontal crashes. Lower extremities were the leading injured body region. The risk of lower limb injuries was significant in all crash modes. A detailed examination of these lower extremity injuries was then conducted using the AIS-90 injury codes. The long term consequence of lower extremity injuries was estimated using the Functional Capacity Index (FCI) associated with each AIS-90 injury code. The effect of a particular injury on society was reported in terms of total Functional Life-years Lost to Injury (LLI) which is defined as the product of FCI and the injured person’s life expectancy.

The National Highway Safety Administration (NHTSA) is collecting crash data relating to large trucks. Two data collection programs are specified. One is a crash causation study to investigate the cause of fatal and serious large truck crashes over two years. The other study is a continuous effort collecting data on large truck motor carrier crashes in each state, as coded on police accident reports.

The objective of this study was to evaluate the performance of various configurations of a driver restraint system by using a combined injury criteria index and making the restraint system adaptive to different frontal crash coinditions, such as severity of the crash, belt use, sitting position, pre-impact braking and size of the driver. For this purpose, a mathematical model of a driver restraint system was developed. The study was divided into three steps: 1. A FE-model of the driver airbag was developed by using MADYMO 3D program; 2. The model was validated by comparing the simulations to crash tests; 3. Effects of design changes in an adaptive restraint system on injury parameters were investigated in simulations of frontal car impacts. It was found that the performance of the restraint system was most influenced by the size of the ventilation hole and the capacity of the gas generator.

A new "On-The-Spot' (OTS) accident research project is now underway in the UK. This project enables expert investigators to attend the scene of an accident within 15 minutes of the incident occurring, which allows the collection of accident data that would otherwise be quickly lost. This paper considers previous studies and the justification for a new research approach before describing methodology used on the spot and during subsequent follow-up research. Investigations focus on all types of vehicles (including damage, failures, features fitted and their contribution); the highway (including design, features, maintenance and condition); the human factors (including drivers, riders, passengers and pedestrians); and the injuries sustained. Five hundred crashes will be studied in depth each year. The project objectives include establishing an in-depth database that will permit analyses to better understand the causes of crashes and injuries, and assist in the development of solutions.

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.

The problem of incompatibility between different car types has become an important issue in the society. In two- car crashes, the aggressivity to the other vehicles is a factor often mentioned. In this study aggressivity is defined as the influence on injury outcome in the other vehicle due to differences in car structure and mass of the studied vehicle. The study was based on police-reported two-car collisions in Sweden. The influence of car mass and structure on driver relative injury risk was for some vehicle categories analyzed with a new developed technique where the influence of mass and structure was separated. SUVs were found to have 32% higher mass factor and 23% higher structural aggressivity factor than the average value, resulting in a 62% higher total aggressivity factor than the average.

Two increasingly important areas of vehicle crashworthiness are the study and modelling of rollovers, as next generation vehicles are being designed with rollover countermeasures This paper describes the corkscrew rollover phenomena, and the analysis techniques used to model it. In the ADAC corkscrew rollover test, two wheels of the test vehicle strike a 6 m long ramp which is 1.19 m high at the launch point. After travelling up the ramp, typically at around 80 km/h, the vehicle rolls onto its roof. Papers exist on the modelling of lateral rollovers, but only one reference is known to the authors on modelling a corkscrew rollover [1].

With a short deformation zone within the lateral zone of a vehicle great demands are made to the control units and sensors of the side airbag systems according to the reaction time until activation. For further development of those systems and keeping the possibility of erroneous activation low these airbag systems are tested in several impacts that cause airbag activations and in so-called misuse tests. One requirement for non-activation is thereby to hit a curbstone with a vehicle. Since there is only little load for the occupants to expect an activation of the sidebag is not necessary. Executing sled crash tests the Institut für Kraftfahrwesen Aachen (ika) simulates realistically those impact situations. Beside different variations of the boundary test conditions further information referring the sensors positions and signal curves for tuning of the airbag electronics are to determine.

The UK External Vehicle Speed Control has made a prediction of the accident savings with ISA, and estimated the costs and benefits of national implementation. The best prediction of accident reduction was that the fitting on all vehicles of a simple mandatory ISA, with which it would be impossible for vehicles to exceed the speed limit, would save 20% of injury accidents and 37% of fatal accidents. A more complex version of mandatory ISA, including a capability to respond to current network and weather conditions, would result in a reduction of 36% in injury accidents and 59% in fatal accidents. The implementation path recommended by the project would lead to compulsory usage in 2019. The cost benefit analysis carried out showed that the benefit-cost ratios for this implementation strategy were in a range from 7.9 to 15.4, i.e. the payback for the system could be up to 15 times the cost of implementing and running it.

The relation between impact severity and risk of injury is a fundamental issue in terms of comparing vehicles and occupant protection systems. Normally, such risk functions would have to be based on reconstruction of crashes, limiting the possibility to generate risk functions down to individual car models. In this study, an alternative way to derive risk functions was developed and used. In the present method, risk functions were derived using matched pairs of crashes, varying mass relations in a controlled way, and generating risk versus relative change of velocity. The data used were police reported crashes in Sweden during 1994-2000. The results show, that there are major differences in injury risk functions between individual car models. The results are of major importance for the development of car model safety rating and for the evaluation of new car safety technology. The method is also of importance in understanding possible scenarios of sub optimization.

The New Car Assessment Program in Japan (JNCAP) was launched in 1995 in order to improve car safety performance. According to this program, installation conditions of safety devices and the results for braking performance and full- frontal crash tests are published every year. Introduction of JNCAP significantly increases the installation rate of safety devices and contributes much in enhancement of safety as seen in the decrease in the average injury severity of drivers and passengers. Side impact and offset frontal crash tests were introduced in 1999 and 2000, respectively. At present, the overall crash safety rating is carried out based on the results of the full-frontal, offset frontal, and side impact tests.

This paper describes ongoing research conducted by the National Highway Traffic Safety Administration (NHTSA) to evaluate the potential of safety restraints on large school buses. School bus transportation is one of the safest forms of transportation in the United States. Large school buses provide protection because of their visibility, size, and weight, as compared to other types of motor vehicles. Additionally, they are required to meet minimum Federal Motor Vehicle Safety Standards (FMVSS) mandating compartmentalized seating, emergency exits, roof crush and fuel system integrity, and minimum bus body joint strength.

This paper summarizes a future side impact test procedure based on the Japanese presentation at the recent IHRA Side Impact WG meeting. Under current Japanese regulations, the MDB specifications and test procedures were determined based on a market study more than ten years ago. Thus, they may not reflect current automobile characteristics, the actual accident situation, and crash test results. In this study (1) the vehicle types, velocity of striking and struck vehicles, body injury regions, causes of injuries, etc., are reviewed with reference to the latest Japanese side impact accident data. The occupant percentages for the non-struck-side, rear seat and for female occupants as well as the injury levels were analyzed. (2) To determine the MDB specifications, based on data from passenger car models registered in 1998, the curb mass, geometry and stiffness were examined. (3) For factorial analysis, side impact tests were performed as for real accidents.

The Japan New Car Assessment Program (JNCAP) was launched in 1995 in order to improve car safety performance. According to this program, installation conditions of safety devices and the results for braking performance and full- frontal crash test are published every year. The side impact test was introduced in 1999. In 2000, the offset frontal crash test was also introduced. From the viewpoint of such a diversification of the crash tests, an overall assessment method for the safety of cars which reflects road accidents has been demanded. In this study, we have examined a new overall assessment method capable of reflecting the traffic accident situation in Japan using methods employed or planned by USA-NCAP, Euro-NCAP, TUB-NCAP and others as references. As the basic concept, JNCAP conducts three types of crash tests including the full-frontal crash test, offset frontal crash test, and side impact test to assess the dummy injury parameters.

Despite the steadily declining number of pedestrian fatalities and injuries in most European countries during the recent decades, pedestrian protection is still of great importance in the European Union as well as in Germany. This is because they still constitute a large proportion of road user casualties and are more likely to suffer serious and fatal injuries than most other road users. In 1999 only car occupants suffered more fatal injuries than pedestrians in Germany. In December 1998, EEVC WG 17 completed their review and updating of the EEVC WG10 pedestrian test procedure that made it possible to evaluate the protection afforded to pedestrians by the front of passenger cars in an accident. Within the scope of this procedure four different impactors are used representing those parts of the body, which are injured very often and/or very seriously in vehicle-pedestrian-collisions.

The offset frontal crash test used by both Australian NCAP (ANCAP) and EuroNCAP has both a front seat passenger and driver dummy while the offset frontal crash test used by the IIHS has only a driver dummy. Additionally Japan NCAP will also include the offset frontal test into their program. All of these consumer crash test programs use the same basic test protocols for the offset frontal test based on the EEVC test which has been included as ECE R94/01, but at the higher test speed of 64 km/hr. However, one major difference between the ANCAP/EuroNCAP programs and the IIHS program is the use of a front seat passenger dummy. This paper reviews influence of the passenger dummy on the NCAP ratings given to cars that have been part of both the ANCAP and EuroNCAP programs. This was done through an evaluation of the passenger dummy results from the ANCAP tests and the EuroNCAP tests and how these results were used in the evaluation process.

Deformable barrier, 64 km/h offset crash tests are conducted under international New Car Assessment Programs. Injury and deformation data from more than 140 offset crash tests carried out since 1995 by EuroNCAP, the Insurance Institute for Highway Safety and Australian NCAP have been analyzed. Trends for head protection, leg protection and structural performance are discussed. The test results confirm that increased uptake of front airbags in Australia has brought about an improvement in head protection. Improvements in structural performance appear to have led to improved leg and foot protection globally. Vehicle designs have evolved to provide better occupant protection in offset crashes. Consumer crash test programs have accelerated this process.

The risk of injury to child car occupants can be markedly reduced by their use of appropriate child restraints. These can be child seats with their own integral harness, child booster seats or booster cushions in association with adult seat belts or, if the child is old and large enough, by the use of adult seatbelts alone. However, the protection afforded can be negated if there is significant loading to the child and restraint through the car seat backrest. This paper describes analyses of accident data to demonstrate the occurrence of this effect in field accidents and presents the results of dynamic tests performed to explore the effect on different restraint types of limiting the load intrusion from the rear. Results of tests with child seats with integral harnesses show that head forward excursion is the main concern, the R44 limits being impossible to meet if the seat back is allowed to move as far forward as the R-point.