The vehicle frontal impact safety evaluation and design method based on the coupling effect between crash pulse and restraint system characteristic

This paper presents a new method to evaluate the design stiffness of vehicle structure and restraint system from the perspective of coupling effect, at the preliminary stage of safety design. The fast iteration algorithm is established to calculate occupant response database. Subsequently, the expressions about three indexes are derived to evaluate the crash pulse, the restraint system and the coupling effect between them. Based on the data from National Highway Traffic Safety Administration (NHTSA) frontal crash impact tests, the star-estimate map is established to estimate the star rating and design stiffness. Finally, a safety design example of M6 model is optimised to verify the validity of the proposed method, and the relative risk score (RRS) of design solution decreases by 43.6%. The proposed method can be used in the phase of conceptual design, greatly reduce the calculation amount of CAE analysis and shorten the product development cycle.