Filtern
Erscheinungsjahr
Dokumenttyp
Sprache
- Englisch (19) (entfernen)
Schlagworte
- Deutschland (19) (entfernen)
Institut
- Abteilung Fahrzeugtechnik (19) (entfernen)
In the paper it is investigated to what extend one can extrapolate the detailed accident database GIDAS (German In-Depth Accident Study), with survey area Hanover and Dresden region, to accident behavior in other regions and countries within Europe and how such an extrapolation can be implemented and evaluated. Moreover, it is explored what extent of accident data for the target country is necessary for such an extrapolation and what can be done in situations with sparse and low accident information in a target region. It will be shown that a direct transfer of GIDAS injury outcomes to other regions does not lead to satisfactory results. But based on GIDAS and using statistical decision tree methods, an extrapolation methodology will be presented which allows for an adequate prediction of the distribution of injury severity in severe traffic accidents for European countries. The method consists essentially of a separation of accidents into well-described subgroups of accidents within which the accident severity distribution does not vary much over different regions. In contrast the distribution over the various subgroups of accidents typically is rather different between GIDAS and the target. For the separation into the subgroups meaningful accident parameters (like accident type, traffic environment, type of road etc.) have been selected. The developed methodology is applied to GIDAS data for the years 1999-2012 and is evaluated with police accident data for Sweden (2002 to 2012) and the United Kingdom (2004 to 2010). It is obtained that the extrapolation proposal has good to very good predictive power in the category of severe traffic accidents. Moreover, it is shown that iterative proportional fitting enables the developed extrapolation method to lead to a satisfactory extrapolation of accident outcomes even to target regions with sparse accident information. As an important potential application of the developed methodology the a priori extrapolation of effects of (future) safety systems, the operation of which can only be well assessed on the basis of very detailed GIDAS accident data, is presented. Based on the evaluation of the presented extrapolation method it will be shown that GIDAS very well represents severe accidents, i.e. accidents with at least one severely or fatally injured person involved, for other countries in Europe. The developed extrapolation method reaches its limits in cases for which only very little accident information is available for the target region.
The EVERSAFE project addressed many safety issues for electric vehicles including the crash and post-crash safety. The project reviewed the market shares of full electric and hybrid vehicles, latest road traffic accident data involving severely damaged electric vehicles in Europe, and identified critical scenarios that may be particular for electric vehicles. Also, recent results from international research on the safety of electric vehicles were included in this paper such as results from performed experimental abuse cell and vehicle crash tests (incl. non-standardized tests with the Mitsubishi i-MiEV and the BMW i3), from discussions in the UN IG REESS and the GTR EVS as well as guidelines (handling procedures) for fire brigades from Germany, Sweden and the United States of America. Potential hazards that might arise from damaged electric vehicles after severe traffic accidents are an emerging issue for modern vehicles and were summarized from the perspective of different national approaches and discussed from the practical view of fire fighters. Recent rescue guidelines were reviewed and used as the basis for a newly developed rescue procedure. The paper gives recommendations in particular towards fire fighters, but also to vehicle manufacturers and first-aiders.
The term driver assistance systems in the chapter title shall be understood to include vehicle automation. This chapter starts with a homogeneous and consistent classification and nomenclature of all kinds of driver assistance systems known and under discussion today (including vehicle automation). It thereby builds upon familiar classification schemes by the German Federal Highway Research Institute (BASt) and the standardization body SAE international. Detailed evaluation of the German legal situation for driver assistance systems and vehicle automation is provided in the following Sect. 2. In Sect. 3, an overview is given on the legal system in the US to reveal aspects relevant for vehicle automation. This is intended as initial information for those not acquainted to the US legal system which has been the first to regulate automation in several federal states. Finally, in Sect. 4, the current rating scheme of the European New Car Assessment Programme (EuroNCAP) is presented in comparison to legal instruments. The model of a consumer protection based approach proves to be a flexible instrument with great advantages in promoting new technologies. Technical vehicle regulations on the other hand rule minimum requirements. Both approaches are needed to achieve maximum vehicle safety.
Camera-monitor systems (CMS) can be used in motor vehicles to display the driver's rear view on a monitor mounted inside the vehicle. This also offers the possibility of replacing conventional exterior mirrors with suitable CMS and thereby implementing new design concepts with aerodynamic advantages. However, as exterior mirrors are safety-relevant vehicle parts for securing the driver's indirect rear view (requirements specified in UN Regulation No. 46), the question arises whether CMS can provide an equivalent substitute for mirrors. In the scope of this study, CMS and conventional exterior mirrors were compared and assessed in test drives and static tests under different external conditions. On the one hand, the examination of technical aspects, and on the other hand, issues pertaining to the design of the human-machine interaction, were the objects of the study. Two vehicles were available for the trials with passenger vehicles: A vehicle, manufactured in small series, which is already equipped with CMS as sole replacement for the exterior mirrors, as well as a compact class vehicle which had a CMS retrofitted by the car manufacturer in addition to conventionally used exterior mirrors. The latter could be covered exclusively for trips with CMS. A tractor unit with semitrailer was available for the truck trials. The driver's cabin was equipped with a CMS system developed by the vehicle manufacturer. In general, it was shown that it is possible to display the indirect rear view sufficiently for the driver, both for cars and trucks, using CMS which meet specific quality criteria. Depending on the design, it is even possible to receive more information about the rear space from a CMS than is possible with mirror systems. It was also shown that the change from mirrors to CMS requires a certain period of familiarisation. However, this period is relatively short and does not necessarily result in safety-critical situations.
Regarding to the German road traffic licensing regulations it is mandatory to have a light system using a bicycle in public traffic. All attached components must be approved. The admission requires additional restrictions such as a dynamo as energy source with a nominal voltage of 6 V. Batteries are only allowed in addition to this. To adopt the German bicycle regulation to the state of art of an energy efficient lighting, additional power sources such as a battery respectively rechargeable batterie should be evaluated. The project will propose amendments for German Road Traffic Regulations and technical requirements.
The project UR:BAN "Cognitive assistance (KA)" aims at developing future assistance systems providing improved performance in complex city traffic. New state-of-the-art panoramic sensor technologies now allow comprehensive monitoring and evaluation of the vehicle environment. In order to improve protection of vulnerable road users such as pedestrians and cyclists, a particular objective of UR:BAN is the evaluation and prediction of their behaviour and actions. The objective of subproject "WER" is development support by providing quantitative estimates of traffic collisions at the very start and predict potential in terms of optimized accident avoidance and reduction of injury severity. For this purpose an integrated computer simulation toolkit is being devised based on real world accidents (GIDAS as well as video documented accidents), allowing the prediction of potential effectiveness and future benefit of assistance systems in this accident scenario. Subsequently, this toolkit may be used for optimizing the design of implemented assistance systems for improved effectiveness.
The use of proper child restraint systems (CRS) is mandatory for children travelling in cars in most countries of the world. The analysis of the quantity of restrained children shows that more than 90% of the children in Germany are restrained. Looking at the quality of the protection, a large discrepancy between restrained and well protected children can be seen. Two out of three children in Germany are not properly restrained. In addition, considerable difference exists with respect to the technical performance of CRS. For that reason investigations and optimisations on two different topics are necessary: The technical improvement of CRS and the ease of use of CRS. Consideration of the knowledge gained by the comparison of different CRS in crash tests would lead to some improvements of the CRS. But improvement of child safety is not only a technical issue. People should use CRS in the correct way. Misuse and incorrect handling could lead to less safety than correct usage of a poor CRS. For that reason new technical issues are necessary to improve the child safety AND the ease of use. Only the combination of both parts can significantly increase child safety. For the assessment of the safety level of common CRS, frontal and lateral sled tests simulating different severity levels were conducted comparing pairs of CRS which were felt to be good and CRS which were felt to be poor. The safety of some CRS is currently at a high level. All well known products were not damaged in the performed tests. The performance of non-branded CRS was mostly worse than that of the well known products. Although the branded child restraint systems already show a high safety level it is still possible to further improve their technical performance as demonstrated with a baby shell and a harness type CRS.
Within this paper different European accident data sources were used to investigate the causations and backgrounds of road traffic accidents with pedestrians. Analyses of high level national data and in-depth accident data from Germany and Great Britain was used to confirm and refine preliminary accident scenarios identified from other sources using a literature review. General observations made included that a high proportion of killed or seriously injured pedestrian casualties impacted by cars were in "dark" light conditions. Seven accident scenarios were identified (each divided into "daylight" and "dark" light conditions) which included the majority of the car front-to-pedestrian crash configurations. Test scenarios were developed using the identified accident scenarios and relevant parameters. Hypothetical parameters were derived to describe the performance of pedestrian pre-crash systems based on the assumption that these systems are designed to avoid false positives as a very high priority, i.e. at virtually all costs. As result, three "Base Test Scenarios" were selected to be developed in detail in the AsPeCSS project. However, further Enhanced Test Scenarios may be needed to address environmental factors such as darkness if it is determined that system performance is sensitive to these factors. Finally, weighting factors for the accident scenarios for Europe (EU-27) were developed by averaging and extrapolation of the available data. This paper represents interim results of Work Package 1 within the AsPeCSS project.
New vehicle types are extensively tested to check almost all factors that influence ride and handling. With reference to the Association of German Car Tuners" (VDAT e.V.) valuations, approximately 10% of all cars in Germany are being modified by their owners. 28 % of those modifications" sales are divergent wheel-tire combinations, 13 % are tuning measures on the chassis suspension or wheel spacers. In almost all cases the singular modifications present a general permission for specific vehicles they have been tested in. Combined tuning measures, however, are often checked by just one inspector, following a procedure of mostly subjective assessment criteria. Today, critical attributes are only being observed, in case a vehicle is involved in an accident and the modifications are identified as crash causal factors or as a cofactor on the development of a crash. For the first time, a field study allows a survey of safety affecting chassis modifications. The test layout has to comply with some basic conditions. Different vehicle concepts with a wide margin of modifications are required to get a high transferability of the results. A total amount of more than 150 tested vehicles serves the same purpose. The tests are limited concerning the installation time of measurement techniques and the requirement that no damage, defilement or immoderate wear of the vehicles are accepted by their owners. Due to such factors as well as the driver Ìs acceptance, the vehicles are controlled by its owners instead of robots or test drivers. For keeping down the driver- influence, the lane has narrow boundaries and the driver has to drive in strictly adherence to the given instructions. After gathering all modifications, as well as static and kinematic parameters like the toe and camber angle, dynamic testing of predominantly lateral dynamics is conducted. Besides standardized tests like the ISO 3888-2 (Obstacle Avoidance) or the ISO 14512 (Braking on Surfaces with Split Coefficient of Friction), to test the influence of modified kingpin offsets caused by wheel spacers, some deviant tests are conducted. Those are required due to the demand of objective test results for road tests with vertical induced stimulation of the chassis suspension. Hence, new tests on corner braking with and without vertical stimulation have been developed. The interpretation of data includes thresholds, e.g. the maximum entrance velocity without hitting cones, on the one hand, and the analysis of characteristics of data concerning time and frequency range, "1-second values" and peak response times on the other hand. Besides the thresholds as indicators for the achievable velocities, which are mainly affected by friction coefficients, the vehicle reaction in the course of time characterizes the vehicle reaction in the threshold range and consequently the operational demands on the driver. The field study has started and promises the first long-range analysis of chassis modifications. The results offer a basis for hypothesis and resultant further test layouts for oncoming studies of the identified critical tuning measures.
Thoracic injury is one of the predominant types of severe injuries in frontal accidents. The assessment of the injury risk to the thorax in the current frontal impact test procedures is based on the uni-axial chest deflection measured in the dummy Hybrid III. Several studies have shown that criteria based on the linear chest potentiometer are not sensitive enough to distinguish between different restraint systems, and cannot indicate asymmetric chest loading, which has been shown to correlate to increased injury risk. Furthermore, the measurement is sensitive to belt position on the dummy chest. The objective of this study was to evaluate the optical multipoint chest deflection measurement system "RibEye" in frontal impact sled tests. Therefore the sensitivity of the RibEyesystem to different restraint system parameters was investigated. Furthermore, the issue of signal drop out at the 6 th rib was investigated in this study.A series of sled tests were conducted with the RibEye system in the Hybrid III 50%. The sled environment consisted of a rigid seat and a standard production three-point seat belt system. Rib deflections were recorded with the RibEye system and additionally with the standard chest potentiometer. The tests were carried out at crash pulses of two different velocities (30 km/h and 64 km/h). The tests were conducted with different belt routing to investigate the sensitivity of chest deflection measurements to belt position on the dummy chest. Furthermore, different restraint system parameters were investigated (force limiter level, with or without pretensioning) to evaluate if the RibEye measurements provide additional information to distinguish between restraint system configurations . The results showed that with the RibEye system it was possible to identify the effect of belt routing in more detail. The chest deflections measured with the standard chest potentiometer as well as the maximum deflection measured by RibEye allowed the distinction to be made between different force limiter levels. The RibEye system was also able to clearly show the asymmetric deflection of the rib cage due to belt loading. In some configurations, differences of more than 15 mm were observed between the left and side areas of the chest. Furthermore, the abdomen insert was identified as source of the problem of signal drop out at the 6th rib. Possible solutions are discussed. In conclusion, the RibEye system provided valuable additional information regarding the assessment of restraint systems. It has the potential to enable the evaluation of thoracic injury risk due to asymmetric loading. Further investigations with the RibEye should be extended to tests in a vehicle environment, which include a vehicle seat and other restraint system components such as an airbag.