Protection in the case of a frontal crash is directly related to the way the occupant is coupled with the decelerating vehicle. Experimental data coming from car crashes carried out in a crash test facility are analysed. This produces an analytical formulation of the coupling phenomenon, which is studied by considering the chest deceleration. The link between the shape of the vehicle deceleration curve and this criterion is established, also taking into account belt slackness. The relative velocity of the dummy in the car right at the moment when coupling begins to appears to be an important factor in determining chest deceleration. A methodology is given that enables engineers to easily account for these results and to have guidelines for improving protection at the preliminary design stage of a car. (A)
Abstract