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In North America, frontal crash tests in both the regulatory environment and consumer-based safety rating schemes have historically been based on full-width and moderate-overlap (40%) vehicle to barrier impacts. The combination of improved seat-belt technologies, notably belt tensioning and load limiting systems, together with advanced airbags, has proven very effective in providing occupant protection in these crash modes. Recently, however, concern has been raised over the contribution of narrower frontal impacts, involving primarily the vehicle corners, to the incidence of fatality and serious injury as a result of the potential for increased occupant compartment intrusion and performance limitations of current restraint systems. Drawing on data documented in the National Automotive Sampling System (NASS)/ Crashworthiness Data System (CDS) for calendar years 1999 to 2012, the present study examines the characteristics of existing and proposed corner crash test configurations, and the nature of real-world collisions that approximate the test environments. In this analysis, particular emphasis is placed on crash pulse information extracted from vehicle-based event data recorders (EDR's).
The number of road accidents in Portugal has decreased significantly in the last decades, however, this tendency is not similar in all types of transportation. In the most recent years and by European standards, Portugal is still one of the leading countries concerning the number of fatalities in Powered Two Wheelers (PTW) accidents. To this effect, the in-depth investigation of PTW accidents is crucial and so, a thorough statistical analysis concerning the main factors influencing PTW riders injury severity accidents was undertaken regarding the 2007-2010 period in the National Road Safety Authority (ANSR) injured riders database using the software SPSS. In addition, to determine the importance of absent factors in the database analysis, such as velocity, a set of 53 real accidents involving PTW were also investigated and computationally reconstructed using the software PC-Crash. Lateral collisions between a motorcycle, its rider and the side of three different passenger cars were also simulated, varying the motorcycle impact angle and velocity in order to estimate the PTW deformation energy and the rider- injuries, as this accident configuration stands out in terms of frequency and even severity. The results of this detailed study are presented.
The overall purpose of the ASSESS project is to develop a relevant and standardised set of test and assessment methods and associated tools for integrated vehicle safety systems, primarily focussing on currently available pre-crash sensing systems. The first stage of the project was to define casualty relevant accident scenarios so that the test scenarios will be developed based on accident scenarios which currently result in the greatest injury outcome, measured by a combination of casualty severity and casualty frequency. The first analysis stage was completed using data from a range of accident databases, including those which were nationally representative (STATS19, UK and STRADA, SE) and in-depth sources which provided more detailed parameters to characterise the accident scenarios (GIDAS, DE and OTS, UK). A common analysis method was developed in order to compare the data from these different sources, and while the data sets were not completely compatible, the majority of the data was aligned in such a way that allowed a useful comparison to be made. As the ASSESS project focuses on pre-crash sensing systems fitted to passenger cars, the data selected for the analysis was "injury accidents which involved at least one passenger car". The accident data analysis yielded the following ranked list of most relevant accident scenarios: Rank Accident scenario 1 Driving accident - single vehicle loss of control 2 Accidents in longitudinal traffic (same and opposite directions) 3 Accidents with turning vehicle(s) or crossing paths in junctions 4 Accidents involving pedestrians The ranked list highlights the relatively large role played by "accidents in longitudinal traffic", and "accidents with turning vehicle(s) or crossing paths in junctions" (the second and third most prevalent accident scenarios, respectively). The pre-crash systems addressed in ASSESS propose to yield beneficial safety outcomes with specific regard to these accident scenarios. This indicates that the ASSESS project is highly relevant to the current casualty crash problem. In the second stage of the analysis a selection of these accident scenarios were analysed further to define the accident parameters at a more detailed level .This paper describes the analysis approach and results from the first analysis stage.
Pedestrians represent about 20% of the overall fatalities in Europe- road traffic accidents. In this paper a methodology is proposed to understand why the numbers are so high, especially in the south of Europe and particularly in Portugal, . First a detailed statistical analysis using Ordinal Logistic Regression model (OLR) was applied to the gathered data from all Portuguese accidents with victims in the period 2010-2012. In a second stage accident reconstruction computational techniques using pedestrian biomechanical models are used to evaluate the accident conditions that lead to the injuries, such as the speed and the impact location. For biomechanical injury criterions, the AIS (Abbreviated Injury Scale), the HIC (Head Injury Criterion) and other injury criterions based on the resulting accelerations in the pedestrian's body are used. The statistical model reported that there were several predictors that significantly influenced the pedestrian injury severity in the event of a road accident, such as Pedestrian's age, Pedestrian's gender, Vehicle Design/Category or Driver's gender. The use of injury scales and biomechanical criterions in in-depth investigation of road accidents, such as AIS, can significantly improve the quality of the reconstruction process.
The incidence of side impacts was investigated from GIDAS data. Both vehicle-fixed object and vehicle-vehicle collisions were analysed as these are enclosed within the consumer testing program. Vehicle-fixed object collisions were stratified according to ESC availability. Results indicated that vehicles equipped with ESC rarely have pure-lateral impacts. An increase in oblique collisions was seen for the vehicles with ESC whereby most vehicle were driving in left curves. The analysis of vehicle-vehicle collisions developed injury risk curves were developed at the AIS3+ injury severity for the vehicle-vehicle side impacts. Results suggested that greatest injury risk occurred when a Pre Euro NCAP vehicle was struck by a Post Euro-NCAP vehicle. The remaining curves did not show different behaviour, indicating that stiffness increased have been equally combated. This was attributable to the few Post Euro-NCAP vehicles that had a deployed curtain airbag available in the sample. The integration of Euro NCAP testing has shown to improve vehicle crashworthiness for pole collisions, as those vehicles with ESC rarely incur lateral impacts.
India is one of the leading countries reporting highest road accidents & related injuries. TMARG (Tata Motors Accident Research Group) has been recording crashes in association with M/s. Lokamanya Medical Foundation since 2011 with M/s, Amandeep Hospitals since Aug 2013. This study has highlighted some accident types not discussed extensively in literature. Trucks to Truck impacts " Cabin interaction with overhanging loadbody structures and Offset underside impacts for passenger vehicles are seen in significant numbers. The paper discusses these in more detail including severity.
Cycling supports the independence and health of the aging population. However, elderly cyclists have an increased injury risk. The majority of injured cyclists is victim of a single-sided accident, an accident in which there is no other party involved. The aim of the project "Safe and Aware on the bicycle" is to develop guidelines for an advisory system that is useful in preventing single-sided accidents. This system is able to support the elderly cyclist; enabling the cyclist to timely adapt his cycling behaviour and improve cycling safety and comfort. For the development of such advisory system the causes of singles accidents and the wishes of the elderly cyclist must be known. First step to obtain this insight was a literature survey and an GIDAS research. Unfortunately accidentology research with GIDAS did not give the full understanding of the pre-crash situations and (especially the behaviour related) factors leading to the accident. The second step was consultation of elderly cyclist through a questionnaire (n=800), in-depth interviews (n=12) and focus group sessions (n=15). This offered complementary information and a much better understanding of the behavioural aspects. Results concern the behaviour in traffic and identify specific physical (i.e. problems looking backwards over the shoulder) and mental issues. Furthermore, the needs and wishes for support in specific cycling situations were identified. In conclusion; The GIDAS results together with the information obtained contacting the elderly cyclists enabled setting up requirements for an advisory system, which is useful in preventing single-sided accidents.
The number of injured car occupants decreases constantly. Nevertheless, they account for nearly 50% of all fatalities and about 44% of all seriously injured persons in German traffic accidents. Further reductions of casualties require multiple efforts in all parts of traffic safety. In this paper a detailed analysis of the important pre-hospital rescue phase was done. The basis for future improvements is the knowledge about injury causation of car occupants in combination with other corresponding influence factors. For that reason more than 1.200 severe (AIS3+) injuries of frontal car occupants were analyzed. For the most relevant injuries of car occupants multivariate analysis models were created to predict the probability of these injuries in a real crash scenario. In addition to the collision severity different influence factors like impact direction, seat belt usage, age of the occupant, and gender were analyzed. Furthermore, the models were checked regarding the goodness of fit and all results all results were checked concerning their robustness. The prediction models were created on the basis of 5.000 car accidents. Afterwards, the models were validated using 4.000 different car accidents. The prediction of the probability of severe injuries could be used for different applications in the field of traffic safety. One possibility is the implementation of the models in a tool for the on-the-spot diagnosis. The background for the development of such applications is the fact, that there are only limited diagnostic possibilities available at the accident scene. Nevertheless, the rescue forces have to make essential decisions like the alerting of the necessary medical experts, appropriate treatment, the type of transportation and the choice of an adequate hospital. These decisions quite often decide between life and death or influence the long-term effects of injured persons. At this point, indications of expectable injuries could help enormously. To enable even persons with limited technical knowledge to use the tool, a procedure was developed that facilitates the assumption of the given crash severity. Another important possibility for the application of the prediction models is the use for the qualification of information sent by e-call systems.
The United Nations Economic Commission for Europe Informal Group on GTR No. 7 Phase 2 are working to define a build level for the BioRID II rear impact (whiplash) crash test dummy that ensures repeatable and reproducible performance in a test procedure that has been proposed for future legislation. This includes the specification of dummy hardware, as well as the development of comprehensive certification procedures for the dummy. This study evaluated whether the dummy build level and certification procedures deliver the desired level of repeatability and reproducibility. A custom-designed laboratory seat was made using the seat base, back, and head restraint from a production car seat to ensure a representative interface with the dummy. The seat back was reinforced for use in multiple tests and the recliner mechanism was replaced by an external spring-damper mechanism. A total of 65 tests were performed with 6 BioRID IIg dummies using the draft GTR No.7 sled pulse and seating procedure. All dummies were subject to the build, maintenance, and certification procedures defined by the Informal Group. The test condition was highly repeatable, with a very repeatable pulse, a well-controlled seat back response, and minimal observed degradation of seat foams. The results showed qualitatively reasonable repeatability and reproducibility for the upper torso and head accelerations, as well as for T1 Fx and upper neck Fx. However, reproducibility was not acceptable for T1 and upper neck Fz or for T1 and upper neck My. The Informal Group has not selected injury or seat assessment criteria for use with BioRID II, so it is not known whether these channels would be used in the regulation. However, the ramping-up behavior of the dummy showed poor reproducibility, which would be expected to affect the reproducibility of dummy measurements in general. Pelvis and spine characteristics were found to significantly influence the dummy measurements for which poor reproducibility was observed. It was also observed that the primary neck response in these tests was flexion, not extension. This correlates well with recent findings from Japan and the United States showing a correlation between neck flexion and injury in accident replication simulations and postmortem human subjects (PMHS) studies, respectively. The present certification tests may not adequately control front cervical spine bumper characteristics, which are important for neck flexion response. The certification sled test also does not include the pelvis and so cannot be used to control pelvis response and does not substantially load the lumbar bumpers and so does not control these parts of the dummy. The stiffness of all spine bumpers and of the pelvis flesh should be much more tightly controlled. It is recommended that a method for certifying the front cervical bumpers should be developed. Recommendations are also made for tighter tolerance on the input parameters for the existing certification tests.
To improve vehicle safety in frontal collisions, the crash compatibility between the colliding vehicles is crucial. Compatibility aims to improve both the self and partner protection properties of vehicles. Although compatibility has received worldwide attention for many years, no final assessment approach has been defined. Within the Frontal Impact and Compatibility Assessment Research (FIMCAR) project, different frontal impact test procedures (offset deformable barrier [ODB] test as currently used for Economic Commission for Europe [ECE] R94, progressive deformable barrier test as proposed by France for a new ECE regulation, moveable deformable barrier test as discussed worldwide, full-width rigid barrier test as used in Federal Motor Vehicle Safety Standard [FMVSS] 208, and full-width deformable barrier test) were analyzed regarding their potential for future frontal impact legislation. The research activities focused on car-to-car frontal impact accidents based on accident investigations involving newer cars. Test procedures were developed with both a crash test program and numerical simulations. The proposal from FIMCAR is to use a full-width test procedure with a deformable element and compatibility metrics in combination with the current offset test as a frontal impact assessment approach that also addresses compatibility. By adding a full-width test to the current ODB test it is possible to better address the issues of structural misalignment and injuries resulting from high acceleration accidents as observed in the current fleet. The estimated benefit ranges from a 5 to 12 percent reduction of fatalities and serious injuries resulting from frontal impact accidents. By using a deformable element in the full-width test, the test conditions are more representative of real-world situations with respect to acceleration pulse, restraint system triggering time, and deformation pattern of the front structure. The test results are therefore expected to better represent real-world performance of the tested car. Furthermore, the assessment of the structural alignment is more robust than in the rigid wall test.