Abstract
This paper presents a theoretical model which is the basis of a computer program to analyse the behaviour of an automobile when it collides with another vehicle or an obstacle. The model is based on the simulation of the behaviour of different resistant parts of the vehicle structure, employing rigidity and damping elements, with non-linear behaviour laws for the latter. The model studies the collision and evaluates characteristic parameters, such as energy absorbed by the structures, structural deformation, elastic recovery, the loading process, and decelerations during the collision. The model has been developed using the Bond-Graph technique.