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- Driver assistance system (21) (entfernen)
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 evaluation of the expected benefit of active safety systems or even ideas of future systems is challenging because this has to be done prospectively. Beside acceptance, the predicted real-world benefit of active safety systems is one of the most important and interesting measures. Therefore, appropriate methods should be used that meet the requirements concerning representativeness, robustness and accuracy. The paper presents the development of a methodology for the assessment of current and future vehicle safety systems. The variety of systems requires several tools and methods and thus, a common tool box was created. This toolbox consists of different levels, regarding different aspects like data sources, scenarios, representativeness, measures like pre-crash-simulations, automated crash computation, single-case-analyses or driving simulator studies. Finally, the benefit of the system(s) is calculated, e.g. by using injury risk functions; giving the number of avoided/mitigated accidents, the reduction of injured or killed persons or the decrease of economic costs.
Rear-end collisions are the most frequent same and opposite-direction crashes. Common causes include momentary inattention, inadequate speed or inadequate distance. While most rear-end collisions in urban traffic only result in vehicle damage or slight injuries, rear-end collisions outside built-up areas or on motorways usually cause fatal or serious injuries. Driver assistance systems that detect dangerous situations in the longitudinal vehicle direction are therefore an essential safety plus. In view of this, for ADAC, systems that alert drivers to dangerous situations and initiate autonomous braking complement ESC as one of the most important active safety features in modern vehicles. The aim of ADAC is to provide consumers with technical advice and competent information about the systems available on the market. Reliable comparative tests that are based on standardised test criteria may provide motorists with important information and help them make a buying decision. In addition, they raise consumer awareness of the systems and speed up their market penetration. The assessment must focus on as many aspects of effectiveness as possible and include not only autonomous braking but also collision warning and autonomous brake assist. The work of the ADAC accident research is the development of the testing scenarios with direct link to accident situations and the identification of useful test criteria for testing.
The main focus of the benefit estimation of advanced safety systems with a warning interface by simulation is on the driver. The driver is the only link between the algorithm of the safety system and the vehicle, which makes the setup of a driver model for such simulations very important. This paper describes an approach for the use of a statistical driver model in simulation. It also gives an outlook on further work on this topic. The build-up process of the model suffices with a distribution of reaction times and a distribution of reaction intensities. Both were combined in different scenarios for every driver. Each scenario has then a specific probability to occur. To use the statistical driver model, every accident scene has to be simulated with each driver scenario (combinations of reaction times and intensities). The results of the simulations are then combined regarding the probabilities to occur, which leads to an overall estimated benefit of the specific system. The model works with one or more equipped participants and delivers a range for the benefit of advanced safety systems with warning interfaces.
The Swedish National Road Administration (SNRA), the Japanese Automobile Research Institute (JARI) and the Federal Highway Research Institute (BASt) are co-operating in the International Harmonized Research Activities on Intelligent Transportation Systems (IHRA-ITS). Under this umbrella a joint study was conducted. The overall objective of this study was to contribute to the definition and validation of a "battery of tools" which enables a prediction and an assessment of changes in driver workload due to the use of in-vehicle information systems (IVIS) while driving. In this sense \"validation\" means to produce empirical evidence from which it can be concluded that these methods reliably discriminate between IVIS which differ in terms of relevant features of the HMI-design. Additionally these methods should also be sensitive to the task demands imposed on the driver by the traffic situation and their interactions with HMI-design. To achieve these goals experimental validation studies (on-road and in the simulator) were performed in Sweden, Germany and Japan. As a common element these studies focused on the secondary task methodology as an approach to the study of driver workload. In a joint German-Swedish on-road study the Peripheral Detection Task (PDT) was assessed with respect to its sensitivity to the complexity of traffic situations and effects of different types of navigation systems. Results show that the PDT performance of both the German and the Swedish subjects reflects the task demands of the traffic situations better than those of the IVIS. However, alternative explanations are possible which will be examined by further analyses. Results of this study are supplemented by the Japanese study where informational demands induced by various traffic situations were analysed by using a simple arithmetic task as a secondary task. Results of this study show that relatively large task demands can be expected even from simple traffic situations.
The sequence of accident events can be classified by three essential phases, the pre-crash-sequence, the crash-sequence and the post-crash-sequence. The level of reliability of the information in the GIDAS-database (German In Depth Accident Study) is provided predominantly on the passive side. The period to evaluate active safety systems begins already in the pre-crash-sequence. The assessment of the potential of sensor- or communication-based active safety systems can only be accomplished by a detailed analysis of the pre-crash-phase. Hence the necessity to analyze the early period of the accident event in detail arises. This is possible with the help of the digital sketches of the accident site and the simulation of the accident by a simulation method of the VUFO GmbH. After simulating the pre-crash scenario it is possible to generate additional and standardized data to describe the pre-crash-sequences of an accident in a very high detail. These data are documented in a second database called the GIDAS Pre-Crash-Matrix (PCM). The PCM contains various tables with all relevant data to reproduce the pre-crash-sequence of traffic accidents from the GIDAS database until 5 seconds before the first collision. This includes parameters to describe the environment data, participant data and motion or dynamic data. This paper explains the creation of the PCM, the simulation itself and the contents and structure of the PCM. With this information of the pre-crash-sequence for various accident scenarios an improved benefit estimation and development of active safety systems can be made possible.
The presentation deals with the simulation tool rateEFFECT which intends to answer the following questions: Which active safety systems should be developed to maximize safety benefit in real traffic accidents? What is the effectiveness of a specific active safety system in the real world? How many casualties could be avoided by such a system? It is shown that a lot of information is required to simulate existing accidents in order to estimate ADAS effects. This particularly includes numerical values for the pre-crash and in-crash phase. The database GIDAS provides a required minimum number of these parameters for a statistically significant sample.
Proposal for a test procedure of assistance systems regarding preventive pedestrian protection
(2011)
This paper is showing a proposal for a test procedure regarding preventive pedestrian protection based on accident analysis. Over the past years pedestrian protection has become an increasing importance also during the development phase of new vehicles. After a phase of focusing on secondary safety, there are current activities to detect a possible collision by assistance systems. Such systems have the task to inform the driver and/or automatically activate the brakes. How practical is such a system? In which kind of traffic situations will it work? How is it possible to check the effectiveness of such a system? To test the effectiveness, currently there are no generally approved identifiable procedures. It is reasonable that such a test should be based on real accidents. The test procedure should be designed to test all systems, independent of the system- working principle. The vFSS group (advanced Forward-looking Safety Systems) was founded to develop a proposal for a technology independent test procedure, which reflects the real accident situation. This contribution is showing the results of vFSS. The developed test procedure focuses on accidents between passenger cars and pedestrians. The results are based on analysis results of in-depth databases of GIDAS, German insurers and DEKRA and added by analysis of national and international statistics. The in-depth analysis includes many pre-crash situations with several influencing factors. The factors are e. g. speed of the car, speed of the pedestrian, moving direction and a possible obscuration of the pedestrian by an object. The results comprise also the different situations of adults and children. Furthermore, they include details regarding influence of the lighting conditions (daylight or night) especially with respect to the accident consequences. In fact, more accidents happen at daylight, but fatal accidents are more often at night. A clustering of parameter combinations was found which represents typical accident scenarios. There are six typical accident scenarios which were merged in four test scenarios. The test scenarios are varying the starting position of the pedestrian, the pedestrian size (adult or child) and the speed of the pedestrian, whereas the speed of the car will not be varied. To ensure the independency from used sensing technologies it is necessary to use a suitable dummy. For example, if sensors are based on infrared, the dummy should emit the temperature of a human being. The test procedure will identify the collision speed as the key parameter for assessing the effectiveness of the tested system. The collision speed is defined as the reduction between initial test speed of the car and impact speed. The assessment of the speed reduction value regarding the safety benefit, however, will be part of a separate procedure.
The Traffic Accident Research Institute at University of Technology Dresden investigates about 1,000 accidents annually in the area around and in Dresden. These datasets have been summarized and evaluated in the GIDAS (German Accident In-Depth Study) project for 13 years. During the project it became apparent that the specific traffic situation of a covert exit of a passenger car and an intersecting two-wheeler involves a high risk potential. This critical situation develops in a large part due to the lack of visibility between the driver and the intersecting bike. In this paper the accident avoidance potential of front camera systems with lateral field of view, which allows the driver to have an indirect sight into the crossing street area will be presented.
Die EU hat für die Verkehrssicherheit in Europa ein anspruchsvolles Ziel vorgegeben: Bis 2010 soll die Anzahl der im Straßenverkehr Getöteten gegenüber 2000 halbiert werden. Für Deutschland kann eine erfolgreiche Zwischenbilanz gezogen werden: In den letzten 5 Jahren nahm trotz Vergrößerung des Kraftfahrzeugbestandes um 6% die Anzahl der Verkehrstoten um 29% ab, in den vergangenen 10 Jahren ist ein Rückgang um 43% zu verzeichnen. Diese im internationalen Vergleich überdurchschnittlichen Erfolge sind nicht zuletzt auch auf Fortschritte in der Fahrzeugtechnik zurückzuführen, wobei die zunehmende Verbreitung von Systemen der Aktiven Sicherheit wie ABS, BAS, ESP einen entscheidenden Anteil hat. Nach der deutlichen Reduzierung von Fahrunfällen durch ESP-® stehen nun die Auffahrunfälle im Fokus der Sicherheitsentwicklung von Mercedes-Benz. Das Paket aus verbessertem rückwärtigen Signalbild (Adaptives Bremslicht) und Brems-Assistent (BAS) wurde kürzlich durch radarbasierte Bremsassistenz ergänzt (BAS PLUS und PRE-SAFE-®-Bremse). Der Beitrag geht auf Funktion und Wirksamkeit der einzelnen Systeme ein und gibt einen Ausblick in die nähere Zukunft.