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Schutz von Fahrzeuginsassen
(1983)
Ausgehend von unfallstatistischen Daten und Ausführungen über Unfallablauf und Unfallfolgen werden Schutzmaßnahmen diskutiert, die das Verletzungsrisiko für Fahrzeuginsassen möglichst niedrig halten. Die Wirksamkeit von Schutzmaßnahmen wird beeinflusst von der Unfallkonstellation, Eigenschaften der Pperson und vom Fahrzeug (Deformationscharakteristik, Auslegung des rückhaltesystems). Die Gesamtwirksamkeit hängt wiederum ab von der Wirksamkeit des Rückhaltesystems, der Benutzungshäufigkeit und der Benutzungsqualität. Die Arbeit endet mit volkswirtschaftlichen Überlegungen und kommt zu dem Schluss, dass auch in Zukunft als wichtigste Maßnahme zum Schutz von Fahrzeuginsassen die Erhöhung der Anlegequote für Sicherheitsgurte anzusetzen ist.
In recent years considerable progress in active and passive safety of road vehicles has been made. The road traffic of today is much safer than in the past. A current vehicle has a lot more safety elements resulting in an improved inner and outer technique. In most European countries the number of fatalities is decreasing despite growing traffic and road usage. Nevertheless, the number of casualties in road traffic accidents is high enough, thus more progress is needed if the number of fatalities is to be reduced by 50%, as postulated by the European Commission for the year 2010. In order to develop countermeasures and further possibilities for injury prevention, it is increasingly important to have accident data available, supplying results quickly and giving the best overview across Europe. In-Depth-Data Sampling Procedures have a huge historical development, starting in the 60ies by the car manufactures, continued during the 70ies mostly by some universities mainly in England, Sweden, France and Germany, today a net of in-depth-investigation teams are working across Europe and around the world.One of the oldest teams is located at the Hannover Medical School, founded in 1973 by the German Government on behalf of the Federal Highway Research Institute Bast. It was the only team worldwide that was equipped with blue light emergency cars, working on scene in time so directly after the event and working continuously during the years, collecting 20 thousand accidents within 30 years period. Since 1999 the order is carried out in cooperation with the German car industry, which is interested and has benefit on the data too. On the basis of the new data collection, so called GIDAS (German In-Depth Accident Study), that has been run at the Technical University Dresden and the Medical University Hannover), a special tool for In-Depth-Accident Analysis was founded. It is the task of this conference to build a platform for such research based on In-Depth-Investigation. The conference is specially aimed at the area of accident data analysis in order to contribute to the harmonization of different investigation methods and accumulation of different results that does exist for different countries worldwide. Up to now no special conference did exist to deal with accident data only following in the discussion for an improvement in traffic and vehicle safety. ESAR - expert symposium on accident research - should be a step forward. This first international conference is being organized by the Accident Research Unit at the Medical University Hannover jointly with the German Federal Highway Research Institute Bast and the Research Association of German Car Manufacturers FAT. The conference should be a platform for an interdisciplinary exchange of information based on the different presentations from participants around the world.
Vehicle crash research at different levels is currently being conducted by several investigation groups in Spain, in some instances within various EU-funded projects. However there is a clear opportunity for increasing compatibility and maximizing usefulness, both at national and European levels, of the information collected by these groups. After reviewing on-going activities and programs in different countries, a framework for a nationwide crash investigation project is proposed: an organizational scheme is suggested as part of a future National Road Safety Strategic Plan; a map of investigation teams located in technological centres, universities and police agencies in Spain is presented; alternatives for several practical aspects such as team composition, deployment and operational budgets and project developmental stages are also discussed.
Detailed investigations and reconstructions of real accidents involving vulnerable road users
(2005)
The aim of this research is to improve knowledge about vulnerable road users accidents and more specifically pedestrians or cyclists. This work has been based on a complete analysis of real accidents. From accidents chosen from an in-depth multidisciplinary investigation (psychology, technical, medical), we have tried to identify the configuration of the impact: car speed, pedestrian or cyclist orientations. Then, we have made a numerical modelling of the same configuration with a multibody software. In particular, we have reproduced the anthropometry of the victim and the front shape of the car. A first simulation has been performed on this starting configuration. Next, effects of some parameters such as car velocity or victim position at impact have been numerically studied in order to find the best correlations with all indications produced by the in-depth analysis. Finally, the retained configuration was close to the presumed real accident conditions because it reproduces in particular the same impact points on the car, the same injuries, and is according to the driver statement. This double approach associating an in-depth accident analysis and a numerical simulation has been applied on pedestrian-to-car and bicyclist-tocar accidents. It has allowed us to better understand the real kinematics of such impacts. Even if this method is based on a case to case study, it underlines which parameters are relevant on a vulnerable road user accident investigation and reconstruction.
In order to improve the protection of children transported in cars, within the CHILD programme (GR3D-CT2002-00791) real world road accidents are thoroughly analysed and then reconstructed in laboratory. Prior to comparing injury severities of real victims to physical parameter values measured on the dummies, the quality of the reconstructions is evaluated by experts who use their experience based on the investigation of numerous and various accidents. This paper presents a new tool aiming at better evaluating and validating accident reconstructions. It is based on statistical evaluation of vehicle deformations which gives weighing factors for every part of the car body structure finally leading to a specific Reconstruction Quality Score (RQS indicator). Furthermore, the reliability of this score, depending on the number of measured points, can be established. This tool includes a function aiming at adjusting the speed for a further reconstruction and at defining the launching speed and the pulse shape for complementary sled tests. Finally, the functions of the RQS software and database are presented.
This study is aimed to investigate the correlations of impact conditions and dynamic responses with the injuries and injury severity of child pedestrians by accident reconstruction. For this purpose, the pedestrian accident cases were selected from Sweden and Germany with detailed information about injuries, accident cars, and accident environment. The selected accident cases were reconstructed using mathematical models of pedestrian and passenger car. The pedestrian models were generated based on the height, weight, and age of the pedestrian involved in accidents. The car models were built up based on the corresponding accident car. The impact speeds in simulations were defined based on the reported data. The calculated physical quantities were analyzed to find the correlation with injury outcomes registered in the accident database. The reconstruction approaches are discussed in terms of data collection, estimating vehicle impact speeds, pedestrian moving speeds and initial posture, secondary ground impact, validity of the mathematical models, as well as impact biomechanics.
Active safety systems are aimed at accident prevention, hence the knowledge required for their development is different from that required for passive safety systems aimed at injury prevention. Particularly, knowledge about accident causation is required. When looking at existing accident causation data, it is argued it fails to explain in sufficient detail how and why the accidents occur. Therefore, there is a need for detailed micro-level descriptions of accident causation mechanisms, and also of methodologies suitable for creating such descriptions. One study addressing these needs is the Swedish project FICA (Factors Influencing the Causation of Accidents and Incidents), where an accident investigation methodology suitable for active safety is developed, and in-depth accident investigations following this methodology are carried out on-scene in the area of Gothenburg by a multidisciplinary team. A preliminary aggregated analysis of different cases shows that the methodology developed is adequate for pointing out common contributing factors and devising principal countermeasures.
Rollover scenarios in Europe
(2005)
Rollover accidents seem to be a rising problem in Europe and therefore the systematic of this accident scenario should be investigated. Based on statistical investigations on major European accident databases for different countries a series of 73 real world rollover accidents was analysed. These cases were reconstructed using PC-Crash and preliminary categorised using a modified USbased rollover classification. In a first step, the rollover events were reconstructed from the point of conflict to the vehicle- rest position. The vehicles kinematics as well as its linear and rotational velocities were derived. In a second step typical velocity characteristics as well as kinematics were identified and the events categorised according to these criteria. Based on these results four main categories were defined, covering all reconstructed accidents. This categorisation was based on mechanical parameters (rotatory and translator kinematical data of the vehicle). Significant differences can be seen for different scenarios for the "first phase of rollover".
Portugal has the highest rate of road fatalities in Europe (2002 and for Eur-15 - CARE database). For this highest rate, the accidents involving pedestrians and motorcycle occupants have a higher contribution than the European average. In the last years, especially accidents involving motorcycles have been investigated and currently two different projects are being carried out, one related with motorcycles accidents and the other with pedestrian accidents. In these projects, countermeasures among others to reduce the fatalities between these two types of road users are being studied. These accidents are investigated with the commercial accident reconstruction software PCCRASH but also new methodologies based on multibody dynamics are in development in order to more accurately study these two types of accidents. In this paper, the methodologies in use for accident reconstruction and new methodologies in development are presented. Speeding his found to be one of the major causes of road fatalities for pedestrians and motorcycle occupants. In the case of motorcycle accidents, these involve mainly young drivers. Aspects as social behavior are also important to understand the causes of some of these accidents. Some examples of accidents occurring in Portugal, involving especially motorcycles and pedestrians are presented and discussed.
The second ESAR Conference took place at the Medical University Hannover. This year conference presents the current state of affairs of relevant research activities in the field of in-depth investigations. The first conference on ESAR (Expert Symposium on Accident Research) was established in 2004. It is planned to hold ESAR every two years. Hannover seems to be the right place for this conference concerning the fact that the first in-depth research team was found here in the year 1973 and comprehensive studies on accident analysis were spread out from here around the world continuously. This year conference topped all expectations in terms of the numbers of participants, in the variety of papers and the interdisciplinary of presenters from medical, psychological and engineering background. More than 100 delegates from all over the world, that means 13 different countries and from 4 different continents, came to Hannover, presented their results of accident investigation and discussed countermeasures for accident prevention and injury reduction. ESAR should be a platform for exchange of knowledge to find an optimized way for increase of traffic and vehicle safety by in-depth investigation and methodology. ESAR as international conference should be a platform for consideration of all nations round the world. This seems to be very important for the current situation, having high safety in the high industrial countries of Europe, US and Australia, but low safety and high injury risk in Asia and Africa.
In Finland all fatal motor vehicle accidents are studied in-depth on-the-spot by multidisciplinary (police, road and vehicle engineers, physician and behavioural scientist) road accident investigation teams (legislation 2001, work started 1968), which operate in every province. The purpose of the teams is to uncover risk factors that turned an ordinary driving situation into a serious accident and give safety recommendations for improving road safety. The investigation teams do not take a stand on guilt or insurance compensation. When analysing accidents the teams use the concepts of key event, immediate, background and injury risk factors. Compiled investigation folders of each case contain investigation forms from each member, preinvestigation protocol, photographs, sketches etc. About 500 items of information are collected from each accident party. The collected information is also coded into a computer database. Both the database and the investigation folders are widely utilized by researchers and authorities conducting safety work.
76 severe traffic accidents had been investigated in depth in an ongoing Volkswagen-Tongji University joint accident research project in JiaDing district, Shanghai, PR China since June 2005. With a methodology similar to German accident research units in Dresden and Hannover, a research team proceeds to the scene immediately after the incident to investigate and collect various data on environment, accident occurrence, vehicle state and deformations as well as injuries. The data combined with the results of accident reconstruction will be stored in a database for further statistical and casuistic analysis. The first outcome of the project supports the hypothesis that a main causation for the large number of traffic accidents in China is the lacking of risk awareness in Chinese driver behaviour. Low seat-belt use and the high proportion of vulnerable and poorly protected two-wheelers in traffic are reasons for the high injury and fatality rate in China. The research work shows that accident research in China is feasible and able to give support to tackle one of the urging problems in Chinese development.
In recent years the boundaries between active and passive safety blurred more and more. Passive safety in the traditional term includes all safety aspects to prevent occupants to be injured or at least injury severity should be reduced. Passive Safety starts with the collision (first vehicle contact) and ends with rescue (open vehicle doors). Within this phase the occupant has to be protected by the passenger compartment whereby no intrusion should occur. Active safety on the other side was developed to interact prior to the collision whereby the goal is to prevent accidents. The extensive interaction between active and passive safety led to the terminologies "Primary" and "Secondary" safety whereas the expression Integrated Safety Concept was generated. Within this study the most well documented single vehicle accidents with cars not equipped with ESP were identified from the PENDANT database and reconstructed. Additional cases were found in the database ZEDATU of TU Graz. In comparison each case was simulated with the assumption that the cars were equipped with ESP. The differences regarding accident avoidance or crash severity as well as reduction of injury risk were analysed.
Description of road traffic related knee injuries in published investigations is very heterogeneous. The purpose of this study was to estimate the risk of knee injuries in real world car impacts in Germany focusing vulnerable road users (pedestrians, bicyclists and motorcyclists) and restrained car drivers. The accident research unit analyses technical and medical data collected shortly after the accident at scene. Two different periods (years 1985-1993 and 1995-2003) were compared focusing on knee injuries (Abbreviated Injury Scale (AISKnee) 2/3). In order to determine the influences type of collision, direction and speed as well as the injury pattern and different injury scores (AIS, MAIS, ISS) were examined. 1.794 pedestrians, 742 motorcyclists, 2.728 bicyclists and 1.116 car drivers were extracted. 2% had serious ligamentous or bony injuries in relation to all injured. The risk of injury is higher for twowheelers than for pedestrians, but knee injury severity is higher for the latter group. Overall the current knee injury risk is low and significant reduced comparing both time periods (27%, p<0,0001). Severe injuries (AISKnee 2/3) were below 1%). Improved aerodynamic design of car fronts reduced the risk for severe knee injuries significantly (p=0,0015). Highest risk of injury is for motorcycle followed by pedestrians, respectively. Knee protectors could prevent injuries by reducing local forces. The classically described dashboard injury was rarely identified. The overall injury risk for knee injuries in road traffic is lower than estimated and reduced comparing both periods. The aerodynamic shape of current cars compared to older types reduced the incidence and severity of knee injuries. Further modification and optimization of the interior and exterior design could be a proper measurement. Classic described injury mechanisms were rarely identified. It seems that the AIS is still underestimating extremity injuries and their long term results.
The accident research project in Dresden was founded in July 1999. To date over 6.000 crash investigations have been undertaken. About 10.000 vehicles have been documented and over 13.000 participants have been debriefed. But there is much more than this scientific success. Because of the interdisciplinary character between the medical and technical focus, the project affords an important contribution for the education of the involved students. Over 200 students of different fields of study have got experiences not only for the occupational career. This lecture describes the additional effects of the accident research project regarding the education of the students, the capacity for teamwork and learning about dealing with accident casualties.
Verkehrsunfallopfer, die beim Unfall überrollt werden, erleiden fast immer tödliche Verletzungen. Im innerstädtischen Bereich ereignen sich diese Unfälle mehrheitlich im niedrigen Geschwindigkeitsbereich. Die Frage der Vermeidbarkeit des Unfalls wird daher sehr oft seitens der Ermittlungsbehörde an die Sachverständigen gestellt. Im Rahmen der Unfallrekonstruktion spielt der Reifenprofilabdruck am Leichnam eine wichtige Rolle. Er belegt nicht nur den Überrollungsvorgang selbst, sondern erlaubt auch die Identifikation der Überrollungsrichtung und -region, aber auch des in Frage kommenden Reifens. Bei der retrospektiven Analyse von 120 Überrollungsfällen in Berlin (Fußgänger, Radfahrer und Kraftradfahrer) aus den letzten 23 Jahren wurde untersucht, wie verlässlich dieses Merkmal ist, wie oft und wo man es findet und von welchen Faktoren seine Entstehung beeinflusst wird.
In September 2004 the first international symposium called ESAR (Expert Symposium on Accident Research) was carried out at the University of Hannover (Germany). The idea for such international conference was to bring together experts from the fields of accident investigation teams worldwide to present their results for a common audience of people from government, industry and other universities. The first conference was a really sufficient one and followed by the second symposium also at the Hannover Medical School two years later in 2006. This two year rhythm was now continued with the third conference in Hannover again in 2008. It is planned to carry out ESAR every two years also in the future. ESAR is a scientific colloquium and can be seen as a platform for exchange of information on accident research issues based on methodologies of investigation, injury mechanisms and injury assessment, accident causation and other issues of statistical accident data analysis. Representatives from authorities as well as from medical and technical institutions come together to discuss new research issues and exchange experiences on accident prevention and the complex field of accident reconstruction. Special focus was given to the target the European Union set for itself in 2000 which stipulates that within 10 years the number of person killed in road traffic accidents must be cut in half. To reach this goal, optimized measures, comprehensive research and analysis are necessary. A key hurdle comes from the European Union extension to 27 member states, each featuring different levels of traffic safety standards and different accident scenarios. Existing results from long term research projects in Europe, the USA, Australia and Japan including analyses of infrastructure, population, vehicle fleet and driver behaviour offer an excellent basis for understanding and improving countermeasures and research support needs in underdeveloped countries. ESAR's goal is to bring together researchers from all parts of the world, who will report on their methods and recommendations to improve traffic safety based on "In-Depth-Investigations" of real world accidents. These In-depth-investigations of accidents require thorough documentation and an accident data analysis on multidisciplinary levels which must be carried out immediately after it occurs. ESAR presents scientists the opportunity to present their studies on a common basis of research level.
Impact severity is a fundamental measure for all in-depth crash investigation projects. One methodology used in the UK is based on the US Calspan software package CRASH3. The UK- in-depth crash investigation studies routinely use AiDamage3 a software package which is based on an updated version of the original CRASH3 algorithm, including enhancements to the vehicle stiffness coefficients. Real world accident-damaged vehicles are measured and their crush is correlated with a library of stiffness coefficients. These measurements are then used, along with other parameters, to calculate the crash energy and equivalent changes of velocity of the vehicles (delta-v), which is a measure of the impact severity. UK in-depth accident studies routinely validate the crash severity methodologies applied as the vehicle fleet changes. This is achieved by analysing crash test data and using the appropriate residual crush damage and other inputs to AiDamage3 and checking the program- outputs with the known crash severity parameters. This procedure checks, at least in part, the default stiffness values in the data libraries and the reconstruction methods used.
A set of recommendations for pan-European transparent and independent road accident investigations has been developed by the SafetyNet project. The aim of these recommendations is to pave the way for future EU scale accident investigation activities by setting out the necessary steps for establishing safety oriented road accident investigations in Member States. This can be seen as the start of the process for establishing road accident investigations throughout Europe which operate according to a common methodology. The recommendations propose a European Safety Oriented Road Accident Investigation Programme which sets out the procedures that need to be put in place to investigate a sample of every day road accidents. They address four sets of issues; institutional addressing the characteristics of the programme; operational describing the conditions under which data isrncollected; data storage and protection; and reports, countermeasures and the dissemination of data.rn
One of the major problems of road safety in Europe is the powered two wheelers accidents. One of the European countries with one of the highest rates is Portugal where in 2006, mopeds and motorcycles fatalities represented 27% of all road users deaths. In this work, a deep analysis and overview of the current state of mopeds and motorcycles accidents for the 2004-2006 period is presented. Within this period 830 PTW occupants die, 2958 have been severely injured and 25000 suffer slight injuries. A detailed analysis of the conditions of these accidents has been carried out, using the data of the national accident database. This analysis provides global information, about geographic environmental conditions, driver- characteristics among others. From this data detailed information is obtained allowing to know when, where and who. In order to answer the question why more a widely collection of data has been collect for 70 accidents. The data has been collected using OECD methodology. For these accidents a detailed reconstruction has been carried out, what is especially important for fatal accidents where for instance speed in an important factor. From these collection and analysis of data a wider overview of facts and measures are extracted. Among them, some are emphasized such as that the quality and non-use of helmets plays an important role in severe and fatal accidents especially for accidents involving moped vehicles, or speed is the most important factor in fatal accidents involving motorcycles. Concerning motorcycle accident reconstruction, different tools can be used depending of the accident scenario and complexity. For simple cases, with specific characteristics, analytical formulation based in vehicle crash dynamics can be use in order to determine the impact speed of the vehicles impact, analysing the skid marks, deformations, victims rest position and considering parameters (EES, vehicle deceleration, etc). Aspects such as the energy absorption capability of motorcycles are also discussed. In the general cases the accident reconstruction software Pc-Crash has been used for the reconstruction of the accident. In very complex cases, has for instance the impact between motorcyclist and barriers, Madymo software is used especially to determine speed from injuries. An example of the impact of a motorcyclist and a motorcyclist-friendly barrier is present to illustrate the benefits and limitations of such systems.