OPTIMISATION OF SIDE STRUCTURE AND SIDE PADDING OF A PASSENGER CAR WITH THE AID OF MATHEMATICAL AND EXPERIMENTAL SIMULATION

The paper describes a theoretical procedure for optimising the side structure stiffness and the side padding of a vehicle. Both parameters were optimised for a given set of test conditions and the functional relationship between the stiffness of the side structure and ideal padding characteristics was determined. The theoretical findings were put into practice by modifying a standard Audi 4000 for crash testing. The modifications incurred a weight penalty of about 13 kg per vehicle, and were very beneficial in the pelvis impact area, gave a slight benefit in the chest impact area, and no benefit in the head impact area. The head loading can only be significantly reduced by direct padding applied in the head impact area. The study has shown that occupant protection in a side-on collision can only be guaranteed by applying very extensive modifications to the vehicle structure and interior. A realistic concept is only possible by combining modifications to the side structure and the side padding. (Author/TRRL)