Abstract
A vehicle model with three motion degrees of freedom is described in this paper. This model is suitable for motion stability analyses in lateral direction as well as the stability of yaw dynamics. By the action of some casual, external perturbations and internal inertial and centrifugal forces, which appear as a consequent of an inadequately adapted ride velocity to the road the motion stability of the vehicle can be disturbed. Here is presented one double-track-model which can be four-wheel-steering, also.