If the amount of energy that has to be converted into deformation work is too high or if the effective surface for the energy exchange is too small, the current concept of passive safety in passenger cars fails. This is already the case within the permissible speed ranges. A transformation into deformation work at lateral areas without breaking into passenger compartment of a vehicle is hardly possible.

Due to legally tolerated speed differences in mixed traffic, it is possible in case of a collision to exceed the amount of energy which can be transformed. Therefore, intrusion into and disrupting of passenger compartments take place in real accidents.

To solve this problem a new safety Concept for passenger cars is being proposed. This concept consists of a combination between diversion of impulse by gliding off and transformation of kinetic energy into deformation work.

For this purpose, the vehicle gets a surrounding main member, which provides the essential portion of structural strength. This surrounding member - board frame - is being designed as a frame. Outwards it is closed, has a smooth surface and is very stiff, especially in lateral areas. It is the idea, that in case of an accident there will he no catching and intrusion between vehicles hut gliding off at each other → gliding zone. Besides the gliding effect front and rear areas of the vehicle:​ provide also the possibility to transform a certain amount of energy into deformation Work, however, without allowing any intrusion or catching.

By combining gliding and crumple zones the speed after collision is being reduced, thus the run-out distance is being shortened. In addition the deceleration of the compartment remains controllable in a biomechanical Sense. At higher speed differences it will be true, too. Intrusion or even disrupting of the passenger compartment is being avoided by the combination of gliding and crumple zones.