Full vehicle dynamics control based on LPV/ℋ∞ and flatness approaches

This paper addresses an integration of two advanced vehicle controllers. The first one is developed for coupled control of longitudinal and lateral vehicle´s motions. It takes advantage of differential flatness of nonlinear systems and algebraic identification techniques for denoising and numerical differentiation. The second one is an LPV/ℋ_∞ controller for suspension system designed to adapt the vehicle vertical dynamics to the lateral dynamics and achieve performance objectives. This LPV/ℋ_∞ aims, mainly, at improving the roadholding of the vehicle (by reducing the lateral load transferor and roll dynamics) or/and passengers comfort depending on the driving situation. Since the lateral forces acting on the vehicle influence the vertical ones (see (13)). The LPV/ℋ_∞ control uses the lateral acceleration (controlled by the flatness controller) to schedule and enhance the vertical dynamic behaviour of the vehicle. Such an integration is proposed in order to ensure an advanced vehicle control under critical driving conditions with different road profiles. This in order to improve the passengers comfort and the stability and steerability of the vehicle in different driving situations. The performance of the proposed strategy is shown through some simulation tests with different scenarios.