Abstract
The behaviour and acting forces of automobile occupants during crashes are studied analytically with reference to a mathematical model in order to save time, cost and space. The model, introduced in this article, is available for use for head-on collisions as well as rear-end collisions, and it is simplified to the minimum degree of freedom which is sufficient to obtain the occupant response. The effects of the seat belt characteristics, the stiffness of the seat back, and the head restraint on occupant protection are described.