NUMERICAL FLEET OPTIMIZATION STUDIES FOR IMPROVED COMPATIBILITY

On behalf of NHTSA and the Dutch Ministry of Traffic and Transport the Safety department of TNO Automotive is performing numerical fleet studies using multi-body models. Aim is to develop strategies for optimization of front-end structures minimizing the total harm in car-to-car crashes on a fleet-wide basis. For these studies multi-body models are being constructed from existing finite element models. Front-end structure and passenger cell are modeled in detail to provide realistic deformation modes. Furthermore dummies, airbags, belts and main interior parts like dashboard and steering wheel are included. Currently four models are available, each of a different vehicle class.

To indicate the performance of the multi-body vehicle models for crashworthiness optimization of a fleet a study on offset frontal impacts is performed. Using the multi-body models a series of parameter sweeps over relevant accident and design parameters were performed. The accident parameters included vehicle type, belt usage and occupant size. The design parameters relate to the front-end geometry of the two smaller vehicles and the front-end stiffness of all vehicles. A total set of 2500 scenarios was simulated.