Pedestrian Protection

Advanced Warning and Control (pedestrian protection, crash avoidance, lane support, track control)... 

T. Helmer, Development of a Methodology for the Evaluation of Active Safety using the Example of Preventive Pedestrian Protection, Springer Theses,... 

The driving state is normally continually monitored (by the driver and/or a system) in order to make corrections on any or all of these levels if required. Detailed applications, variations and refinements of this model can be found in the literature [4, 10-12]. Classically, active safety systems, e.g.. Dynamic Stability Control (DSC), have been designed to provide support at the stabilization level. At this level, the target quantities are generally well defined in terms of vehicle physics. Preventive pedestrian protection, which is in the focus of this thesis, addresses primarily the maneuvering level and thus involves additional eomplexities in control—particularly those involving the interpretation of driver behavior and the interaction of system actions with the driver. 

Fig. 1.6 Top-down structuring of active safety with an example for preventive pedestrian protection...

The minimum requirements for vehicle-based pedestrian protection necessary for vehicle type approval ( homologation ) are defined by laws, e.g., the Regulation (EC) No. 78 009 of the European Parliament and of the Council [37] or the Global technical regulation No. 9 on Pedestrian Safety by the United Nations [38]. Additional requirements are defined by consumer protection agencies like the European New Car Assessment Program (Euro NCAP) [39]. 

At present, pedestrian protection requirements mainly involve optimization and implementation of passive safety measures at vehicle front ends, where most pedestrian impacts occur. The most prominent improvements have involved changes in the shape of the front end and the elimination of sharp or rigid mounted parts, e.g., bull bars [40], in order to minimize obvious sources of injury. Another important passive... 

The first consideration of active safety in regulations is included in (EC) No. 78/2009[37], Chapter III Article 11. All vehicles equipped with collision avoidance systems may not have to fulfill the test requirements laid down in Sections 2 and 3 of Annex I in order to be granted an EC type-approval or a national type-approval for a type of a vehicle with regard to pedestrian protection, or to be sold, registered or to enter into service . It is required that [a]ny measures proposed shall ensure levels of protection which are at least equivalent, in terms of actual effectiveness, to those provided by Sections 2 and 3 of Annex I . Article 11 provides a legal basis for future fulfillment of the regulation by both active and passive safety devices, based on the effectiveness required. 

The approval process for braking assistance can be regarded as a prerequisite for active safety systems. The requirements formulated by the Directive 2003/102/EG, Phase 2, of the European Parliament and of the Council [53] could nearly not be fulfilled by means of passive safety. As a consequence, an evaluation regarding the effectiveness of different measures of pedestrian protection has been carried out [54, 55]. The commitment of the European Automobile Manufacturers Association (ACEA) European Automobile Manufacturers Association to implement brake assist, an active safety system, in every new car, led to a reduction of the requirements... 

The objective of this thesis is the advancement of knowledge in order to enable the development of a method for evaluating active safety systems. The example used is vehicle-based preventive pedestrian protection. 

A new approach to evaluation of active safety is then developed in Chap. 3. The process, including information needed, is described, and the prerequisites are defined. In detail, accident scenarios, configuration of a functional demonstrator of a preventive pedestrian protection system, and the simulative technique required are described. An introduction of a metric for the quantification of the change in safety rounds up the method. 

Chapter 6 illustrates the results of the described evaluation method using different configurations of a preventive pedestrian protection system. The current results, the validity of the methodology used as well as need for further research are described. The results of parameter variations for a preventive pedestrian protection system are given using a functional demonstrator. The findings are interpreted with respect to the methodology. Metrics and processes necessary for system optimization and evaluation are introduced and discussed. 

Davies, H., Holford, K., Assoune, A., Ttioidier, B., Courtney, B. (2009). Pedestrian protection using a shock absorbing liquid (SALi) based bumper system. In 21st International Technical Conference on the Enhanced Safety of Vehicles (ESV 2009) (No. 09-0027). 

Rasshofer, R., Schwarz, D.,Biebl,E.,Morhart,C.,Scherf,O.,Zecha,S.,Griinert, R., Friihauf, H. (2007). Pedestrian protection systems using cooperative sensor technology. In Proceedings of the 11th International Forum on Advanced Microsystems for Automotive Applications (AMAA 07) (pp. 135-145). 

Hannawald, L., Kauer, F. (2004). Equal effectiveness study on pedestrian protection. Dresden Technische Universitat Dresden. 

The next evolution of the method presented by Busch is called PreEffect-iFGS. It is a prospective method for evaluating the field effectiveness of integral pedestrian protection systems [21]. The main procedures of Busch, i.e., selection of relevant accidents, simulation with/without system, translation into injury severity, and calculation of the effectiveness, stayed the same with some additions. The improvement is an incorporation of test results for active and passive safety systems derived from hardware testing [54]. The initial version also includes an automated backwards simulation of each accident based on the values available in GIDAS. The results are then transferred into the commercial software PC-Crash and are then simulated forward with and without the measure in question. 

Kates, R., Jung, O., Helmer, T., Ebner, A., Gruber, C., Kompass, K. (2010). Stochastic simulation of critical traffic situations for the evaluation of preventive pedestrian protection systems. In Erprobung und Simulation in der Fahrzeugentwicklung. 

Euro NCAP. (2009). European New Car Assessment Programme (Euro NCAP) Assessment Protocol—Pedestrian Protection. No. Version 5.0. wrvw.euroncap.com. 

Fredriksson, R. (2011). Priorities and Potential of Pedestrian Protection—Accident data. Experimental tests and Numerical Simulations of Car-to-Pedestrian Impacts. PhD thesis, Karolinska Institutet. 

Fioming, R. (2008). Assessment of integrated pedestrian protection systems. In Fortschritt-Berichte VDI, No. 681 in 12. VDI Verlag GmbH, Diisseldorf. 

Htimacher, M., Eckstein, L., Kiihn, M., Hummel, T. (2011). Assessment of active and passive techniceil measures for pedestrian protection at the vehicle front In 22st International TechniccU Conference on the Enhanced Safety of Vehicles (ESV 2011), No. 11-0057. 

Approach to Integrated Safety Evaluation Preventive Pedestrian Protection... 

Figure3.2 gives some details on the different steps of the process chain for the example of preventive pedestrian protection. Concerning data used, knowledge regarding the driver and pedestrian behavior (if not extractable from accident data) are taken from literature. The vehicle and preventive pedestrian protection related aspects are also based on literature as well as corporate knowledge. The intention is to construct evidence-based models using well-established statistical information to the greatest extent possible. The experiments and methods described in Chaps. 2 and 4 are intended to provide information necessary for developing the different models. In case specific parameters are unknown or for some reason cannot be investigated, sensitivity analyses are utilized to quantify the resulting uncertainties.

Functional Demonstrator of a Preventive Pedestrian Protection System... 

The vehicles in the simulation move on a straight street and have dimensions typical for mid-size vehicles. The braking capabilities are typical for up-to-date vehicles and typical road surfaces. The implemented preventive pedestrian protection system is thus modeled as part of the vehicle. Once the pedestrian is visible for the system, the probability per unit time that the pedestrian is detected by the system is modeled as a constant. The algorithm of the system includes a prediction of the vehicle s movement and the pedestrian s movement as well as the calculation of a collision probability as basis for a system action. The system itself has various stochastic components, e.g., inaccuracies regarding position and speed of the pedestrian. Depending... 

The process chain starts with a reference scenario for the situation in question. For example, in the case of pedestrian protection, the most important scenario is a pedestrian crossing from the right in an urban setting (for Germany and the US). A functional demonstrator of a preventive pedestrian protection system is defined to test the process chain with a measure of active safety. The system detects the pedestrian, warns the driver, preconditions the brake assist, and as a last resort brakes automatically. 

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