Evaluation of Accident Parameters in a Numerical Fleet for Assessing Compatibility

On behalf of NHTSA, the European commission and the Dutch Ministry of Traffic and Transport, the Safety department of TNO Automotive is performing numerical fleet studies using multi-body vehicle models. Currently nine vehicle models are available, each of a different vehicle class, two vehicle models with a modified front-structure.

The aim is to develop strategies for evaluation of front-end structures minimizing the total harm in car-to-car crashes on a fleet-wide basis in different accident scenarios. For these studies multi-body models were constructed from existing finite element models. Front-end structure and passenger cell were modeled in detail to provide realistic deformation modes. Furthermore dummies, airbags, belts and main interior parts like dashboard and steering wheel were included.

To qualify the performance of the multi-body vehicle models for crashworthiness in an entire fleet, a study on offset frontal angled impacts was performed. Several parameter sweeps over relevant accident and design parameters were performed using the multi-body models. The accident parameters included vehicle type, vehicle speed and frontal overlap. The design parameters related to the front-end geometry of the two smaller vehicles and the front-end stiffness of all vehicles. A total set of over 4200 scenarios was simulated. Conclusions drawn from statistical analyses of the numerical results were used to automatically identify typical crash scenarios and to investigate compatibility improvements in two vehicles within the vehicle fleet.