NEW HEADLAMP CONCEPTS AS KEY TO OPTIMISATION OF VEHICLE FRONT ENDS IN CONSIDERATION OF PEDESTRIAN PROTECTION 2001-06-0173

Seeing and being seen well have been playing a decisive role as elements of active safety since the invention of motor cars. In this context, Hella has made a decisive contribution to the high level of performance of today’s headlamps thanks to its numerous innovations of the past 100 years, and has also prepared pioneering concepts for the future [1].

More recent targets reveal, however, that headlamps also play a key role with regard to the passive safety of vehicles – particularly in accidents involving pedestrians. In almost 70% of all pedestrian accidents the primary contact zone is in the corner areas of the vehicle front end.

Using this background knowledge, Hella is working closely with the Institut für Kraftfahrwesen in Aachen to optimise headlamp constructions with regard to energy absorption and deformation behaviour in the event of a crash. Drop tower tests and crash simulation have been carried out within this framework.

For these tests the basic conditions were chosen following the EEVC WG17 tests with the hip impactor. The mechanical interface between the headlamps and the front end module was reproduced for the drop tower tests in such a way that it corresponded to the installation conditions in the vehicle and at the same time was suitable for modelling in crash simulation.

The experimental investigations were used to analyse measures to optimise existing devices. Furthermore, drop tower tests were carried out with the aim of validating FE crash calculation models. More complicated attempts at optimisation for headlamps were able to be examined using the validated FE models.

In this paper, the qualitative results of the investigations and initial solutions derived will be presented. In particular, the basically high elasticity of headlamp casings of classic design and the extremely high ductility of PC cover lenses can be proved.

Different solution concepts will be presented and evaluated. Regulations covering shape and notes about design will be partly explained in detail.