Active systems of the passive vehicle safety for pedestrian protection, so called crash-active pedestrian protection systems, are installed in series vehicles since 2005 to fulfill relevant pedestrian protection requirements (compare regulation (EC) No. 78/2009 and 631/2009). These crash-active pedestrian protection systems act in contrast to solely passive systems only as non-stationary solution. Since, the requirements defined within these directives were developed for stationary systems, potential additional risks of these non-instationary systems could currently not be considered. Within the framework of this research project an evaluation procedure for these crash-active pedestrian protection systems shall be developed. As a basis, a comprehensive investigation of potential additional requirements for valid test procedures shall be conducted. The regarded non-stationary protection methods are only activated in case of a vehicle collision with a pedestrian, which has to be detected reliably. For the contact-based sensors used for this application the detection of pedestrians inducing a small load in the vehicle front is very challenging. These loads depend on numerous parameters, like the height of the load paths inducing the force or the height and the weight of the pedestrian. By conducting comprehensive impact tests and simulations, it is shown that existing test objects cannot fulfill these requirements. Therefore, new test objects have to be developed for a suitable evaluation procedure. With the activation of the protection device these crash-active systems aim to reduce the injury risk of the head impact mainly. For this purpose, the rear bonnet edge is raised in most cases to provide additional deformation space. However, raising the bonnet can also result in additional injury risks, for example due to the exposed rear bonnet edge or the reduction of the deformation space resulting from the impact of the torso of the pedestrian. A substitute test procedure for evaluating the bonnet deformation with the upper leg impactor is presented. A hybrid test procedure consisting of simulation and testing is suitable for an objective evaluation of these systems. The corresponding testing parameters can be evaluated with the prior simulation. (Author/publisher)
Samenvatting