Search Results

For fine-tuning of the parameters of algorithms used for activation of deployable pedestrian protection safety systems, quite a number of impact tests have to be performed on real vehicles. The impactors used for these purposes comprise misuse-objects, hardest-to-detect pedestrian impactors, but also impactors that represent larger pedestrians, such as the WG17 legform or the FlexPLI. Such tests are performed with impact speeds up to 55 kph and at ambient temperatures between −35 °C and 90 °C. Especially for the more complex FlexPLI there is a high risk of damage to the impactor under such conditions. Additionally, the required calibration procedures after such test series and an obligatory exchange of parts (e.g. ligaments) after each test are a source for further costs.

Active bonnet safety systems are implemented into vehicles, to fulfill pedestrian head impact requirements despite little available deformation space. For such systems it is necessary to consider a variety of aspects already from the very beginning of the vehicle design process and the functionality of the whole system needs to be continually cross-checked throughout the whole design process. Many of these aspects are already supported by finite element (FE) methods from vehicle manufacturers and in this paper it is shown, how the last missing links within the development process, the optimization of pedestrian detection sensor signals can also be efficiently supported by FE simulation. The modeling and validation of a pressure tube based sensor system and so called “misuse objects” are demonstrated.