Method to Assess the Effectiveness of Active Pedestrian Protection Safety Systems

The effectiveness analysis assesses the benefit of future safety systems in terms of collision mitigation or collision avoidance based on real life accident data. The safety systems are evaluated by case-by-case analyses based on in-depth accident data (e.g. GIDAS). For this purpose an innovative simulation environment was developed that recreates the technical specification of the proposed system consisting of function algorithm, sensor, and actuators. Therefore results of component tests and complete system tests are included into the simulation. The accidents from the database are varied in the simulation by applying stochastic methods, guaranteeing the validity of the results from a statistical viewpoint. In addition to technical parameters such as a reduction in collision speed, the evaluation also includes a reduction in collision probability. Furthermore, when evaluating the functions a distinction is made between controlled and regulated actions. For each type a special simulation technique is used, which on the one hand is a purely offline analysis of previously simulated data and on the other hand an online or in-the-loop simulation. In order to be able to consider driver reactions on defined warning strategies realistically, it is essential to integrate a driver behaviour model into the simulation. To determine the driver behaviour, studies with probands are conducted using a new simulator technology. The test scenarios for these proband studies are based on accidents of the internal Audi accident research unit (AARU) database. In order to convert the technical evaluation parameters of the accident, e.g. collision speed, to injury severity, injury-risk-functions are required. To sum up, a new method of assessing the effectiveness of integrated safety systems will be presented, which incorporates new simulation techniques, driving experiments and real life accident data to assess a well-founded evaluation of integrated safety systems. INTRODUCTION The requirements arising from pedestrians’ safety legislation and consumer ratings have intense effects on the today’s vehicle development. The design of the vehicle and the technology of the front end especially depend strongly on these measurers and induce trade-offs during the vehicle development process. Further passive measures lead to an increasing vehicle weight or cars being built higher and consequently to higher emissions. Besides secondary collisions of the pedestrians e.g. with the road are not covered by passive measures. Studies based on real accident data proved that systems enhancing the driver’s braking are considerably more effective in pedestrian accidents. These studies lead to the definition of phase 2 regarding pedestrian legislation in the European Community which prescribes the installation of a brake assist system in new cars since November 2009 in combination with reduced passive measures compared to the original proposal of pedestrian legislation phase 2. Consequently a first step in resolving the conflicts of aim described above has been carried out. normal driving condition post crash collision unavoidable critical driving condition unstable driving condition driver conditioning collision avoidance collision mitigation passive safety