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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.
This work aims at bringing evidence for mass incompatibility in frontal impact for cars built according to the UNECE R94 regulation. French national injury accidents database census for years 2005 to 2008 were used for the analysis. The heterogeneity of frontal self-protection among cars of different masses is investigated, as well as the partner protection parameter offered by these cars. The last part of the analysis deals with the estimation of the benefit, in terms of fatal and severe injuries avoided, if crashworthiness was harmonized for the whole fleet of vehicle. This calculation is done for France and is extended to all Europe.
Over the past two decades the popularity of consumer crash test programs, commonly referred to as New Car Assessment Programs (NCAP), has grown across the world. They are popular among government regulators as they afford a means of promoting safety innovations and levels of vehicle performance beyond those dictated by national standards. They also fulfill the demand for information regarding the safety ranking of vehicles among consumers contemplating the purchase of a new vehicle. There is no question that consumer crash test programs greatly influence vehicle design changes as well as accelerate the fitment of new safety features. The extent to which these changes can be expected to reduce serious and potentially fatal injuries will be influenced by how well the testing protocols and associated rating schemes correctly reflect the nature of the residual safety problem they seek to address. Drawing on data contained primarily in the US National Automotive Sampling System (NASS), the field relevance of current and proposed testing and rating protocols addressing frontal crash test protection is examined. Emphasis is placed on examining how accurately injury rates computed from the dummy responses measured in consumer crash tests correspond to actual injury rates observed in the field. Additional data from Canadian field investigations and US databases such as the National Motor Vehicle Crash Causation Survey (NMVCCS) are examined to see how well frontal airbag firing times, crush pulse durations and other determinants of injury are replicated in consumer testing protocols. This portion of the analysis draws on data obtained from Event Data Recorders (EDR) in both field collisions and staged tests of the same vehicle model. Vehicle rankings and overall frontal crash test ratings were found to be particularly sensitive to the choice of injury risk functions employed in the test. This was particularly true in the case of injury risk functions used to assess neck injury potential. Neck injury risk derived from Nij was found to show the least agreement with the field. Agreement between field chest injury rates and those derived from crash tests was improved considerably when chest injury risk functions for "older" occupants were employed. The paper concludes with a discussion of how different current testing protocols could be improved to enhance their field relevance.
In road traffic accidents, a car-seat and its occupant can be subjected to various crash pulses in the case of a rear impact. This study investigates the influence of crash pulse shape on seat-occupant response and evaluates the corresponding risk of whiplash injury. For this purpose, a rigorously validated seat-occupant system model is used to study different carseat designs and crash pulses. Two different car-seat concepts are also presented which can effectively mitigate whiplash injury for a wide range of crash severity. It is shown that for crash pulses of similar severity, the level of whiplash-risk depends strongly on the combined effects of seat design and crash pulse shape.
An analysis of NASS and FARS was conducted to determine crash conditions that involved injuries that are not currently being directly addressed by vehicle safety standards or by consumer information test protocols. Analysis of both field data and US NCAP tests were conducted to determine the relative safety provided by seating position and by vehicle model year. Opportunities for improvements were determined by crash categories with large populations of injuries that were not addressed by safety tests or smaller numbers that were increasing in frequency. Areas of opportunities include improved occupant restrain in rollovers, improved frontal protection for rear seat occupants and improved fire prevention in frontal and rollover crashes.
The share of high-tensile steel in car bodies has increased over the last years. While occupant safety has generally benefited from this measure, there is a potential risk that, as a result, rescue time may increase considerably. In more than 60% of all car occupant fatalities a technical rescue has been necessary. These are in particular those cases where occupants die immediately at the accident scene. Therefore, in these cases "rescue time" is a very sensitive parameter. In addition to the general analysis of the need of technical rescue and the actual rescue time depending on model years, the injury pattern of occupants requiring technical rescue will be analysed to provide advice for rescue teams. Furthermore, a detailed analysis of rescue measures for the most popular car models depending on the safety cell design is given.
The paper presents a methodology for the benefit estimation of several secondary safety systems for pedestrians, using the exceptional data depth of GIDAS. A total of 667 frontal pedestrian accidents up to 40kph and more than 500 AIS2+ injuries have been considered. In addition to the severity, affected body region, exact impact point on the vehicle, and the causing part of every injury, the related Euro NCAP test zone was determined. One results of the study is a detailed impact distribution for AIS2+ injuries across the vehicle front. It can be stated, how often a test zone or vehicle part is hit by pedestrians in frontal accidents and which role the ground impact plays. Basing on that, different secondary safety measures can be evaluated by an injury shift method concerning their real world effectiveness. As an example, measures concerning the Euro NCAP pedestrian rating tests have been evaluated. It was analysed which Euro NCAP test zones are the most effective ones. In addition, real test results have been evaluated. Using the presented methodology, other secondary safety like the active bonnet (pop-up bonnet) or a pedestrian airbag measures can be evaluated.
Providing effective occupant protection in rollover crashes requires supplying the occupant with a restraint system proven effective in the dynamic rollover accident mode. Preventing ejection and providing restraint sufficient to prevent potentially injurious contacts with both interior and exterior vehicle components is paramount for effective rollover occupant protection. Research has shown that the injury potential can be decreased by closely coupling the occupant to the seat. This paper focuses on the effect of restraint system slack and its relationship to occupant excursion and ejection potential during rollover. Various restraint system configurations are evaluated in rollover-type test environments. A review of prior research is presented prior to presenting new quasi-static vehicle inversion studies conducted with live surrogate occupants. Additionally, dynamic rollover testing utilizing anthropometric test devices (ATDs) is presented. The influence of belt looseness and effects of various restraint designs on the belted occupants' injury potential are discussed.
The need of passive safety devices, able to reduce the accidents and the severity of injuries suffered by motorcyclist, distinctly arises from data on accident statistics. In this paper, the effectiveness of an airbag device fitted in the biker- garments has been verified through various numerical simulations. Two simple test conditions were defined, in order to investigate the performance of the device both for back and front impacts, and simulated at various impact speeds. With the aim of providing more information about the actual capability of the airbag to reduce the severity of the injuries, one of accident scenario described by ISO 13232:2005 has been also investigated, checking the real effectiveness of the airbag strap-based firing system too. Confrontation of injury indexes resulting from simulation with and without airbag made possible a realistic evaluation of the harm reduction induced by the airbag presence.
In order to enable foreseeing or comparing the benefit of safety systems or driver assistance systems in Germany, in the United States and in Japan, the traffic accident databases in those three countries are examined. The variables used are culpable party, collision partner, accident type, and injury level and the method to re-classify the databases for comparison are proposed. The result indicates that single passenger car fatality is the most frequent in Germany and in the United States, while passenger car vs. pedestrian is the most frequent fatality scenario in Japan. When the casualty by fatality ratio is focused, the greatest difference is observed in rear-end collisions. The ratio of slight injuries in Japan yields about eighteen times as many as those in Germany, and about eight times as many as those in the United States.
Accident data shows that the vast majority of pedestrian accidents involve a passenger car. A refined method for estimating the potential effectiveness of a technology designed to support the car driver in mitigating or avoiding pedestrian accidents is presented. The basis of the benefit prediction method consists of accident scenario information for pedestrian-passenger car accidents from GIDAS, including vehicle and pedestrian velocities. These real world pedestrian accidents were first reconstructed and the system effectiveness was determined by comparing injury outcome with and without the functionality enabled for each accident. The predictions from Volvo Cars" general Benefit Estimation Model are refined by including the actual system algorithm and sensing models for a relevant car in the simulation environment. The feasibility of the method is proven by a case study on a authentic technology; the Auto Brake functionality in Collision Warning with Full Auto Brake and Pedestrian Detection (CWAB-PD). Assuming the system is adopted by all vehicles, the Case Study indicates a 24% reduction in pedestrian fatalities for crashes where the pedestrians were struck by the front of a passenger car.
An eCall device has been mounted on some vehicles in France since 2003. It is an integrated car radio/GSM/GPS system that can be used with a SIM card. When an accident occurs, a call can be sent manually or automatically made to a telephone call centre. Knowing the geographic location, the vehicle identity and the possibility of a direct communication with the people involved enables the nearest emergency services to be called out. In this context, the LAB / CEESAR have set up a study aimed at evaluating the effectiveness of this system. The purpose of this paper is to detail the E-call system evaluation method of effectiveness used and give a global synthesis of the results.
Females sustain Cervical Spine Distortion injury (CSD) more often than males. Most work dealing with the biomechanics background (e.g. injury mechanism/criteria) as well as the application in seat design/testing, focuses on the occupant model of an average male. Therefore the EU-Project ADSEAT (Adaptive Seat to Reduce Neck Injuries for Female and Male Occupants) is aimed at adding a female model for gender balanced research of CSD and improving seat design. An extensive literature review, searching for risk factors and injury criteria for males and females, was accompanied by the evaluation of different databases containing CSD cases. The database evaluations suggests that an anthropometry quite close to the 50%ile female anthropometry as known from crash test dummy design is appropriate. The results presented here form the basis for the future development of a computational female model and the improvement of seat design for better protection of both males and females in the frame of the ADSEAT-Project.
Neben der zunehmenden Bedeutung der aktiven Sicherheit bleiben Maßnahmen der passiven Sicherheit bei der Entwicklung moderner Kraftfahrzeuge unabdingbar. Die Weiterentwicklung von Maßnahmen zum passiven Fußgängerschutz war zunächst größtenteils durch Verbraucherschutztests wie zum Beispiel Euro NCAP oder JNCAP getrieben und ist nun auch durch gesetzliche Regelungen verpflichtend geworden. Im vorangegangenen Forschungsprojekt der BASt FE 82.229/2002 Schutz von Fußgängern beim Scheibenaufprall ist die Grundlage eines modularen Prüfverfahrens für den Kopfaufprall im Bereich der Windschutzscheibe, bestehend aus einem Versuchs- und einem Simulationsteil, erarbeitet worden. Im Rahmen dieses Projektes wurde ein hybrides Testverfahren bestehend aus Versuch und Simulation ausgearbeitet, das den Bereich der Windschutzscheibe und dabei auch crashaktive Systeme wie Airbags berücksichtigt. Das Testverfahren kombiniert Komponentenversuche mit einem Simulationsteil, in dem Fahrzeug-Fußgänger-Simulationen und lmpaktorsimulationen durchgeführt werden. Zusätzliche Dummyversuche dienten zur Bewertung des Testverfahrens. Alle erarbeiteten virtuellen und realen Testmethoden wurden an einem Referenzfahrzeug (Opel Signum), welches repräsentativ für eine durchschnittliche Mittelklasselimousine steht, durchgeführt. Das Fahrzeug wurde mit einem Airbagsystem ausgerüstet und der Testprozedur mit und ohne diesem System vergleichend unterzogen. Innerhalb dieser Untersuchungen konnte gezeigt werden, dass neue Testmethoden unter Ausnutzung von Simulationen und Komponententests es erlauben, realistischere Versuchsbedingungen unter Berücksichtigung von potenziellen Kopfaufprallpositionen und -zeiten zu definieren. Dabei können sehr gute Übereinstimmungen zwischen Fußgängersimulation und Dummyversuch erreicht werden. Die Randbedingungen für den Kopfaufprall und die Aufprallzeit wurden durch den Einsatz von Fußgängermodellen ermittelt. Weiterhin ermöglichen die Simulationen, zusätzliche Einflussdaten wie Vektoren mit den Kopfaufprallgeschwindigkeiten und -winkeln zu bestimmen.