Model-Based Feed Forward Control Design for the Vertical Dynamics of a Vehicle with Active Suspensions

Modelling a vehicle as a two-track vehicle model leads in terms of the vertical dynamics to five vibratory bodies (the chassis mass and the four wheel masses) and therefore to a system of fourteenth order. By the use of active suspensions forces can be applied between the chassis mass and the four wheel masses. In this paper a model-based feedforward control for these forces is presented that permits a very precisely pre-controlling of the chassis movement initiated by longitudinal and lateral forces even with a high model simplification for the internally used vehicle model into two second order systems. Thereby the steady-state values as well as the dynamic behaviour of the roll and pitching motions can be accurately adjusted within the physical limits of the system.