Sliding mode observers to replace vehicles expensive sensors and to preview driving critical situations

In this paper, tyre longitudinal forces, vehicle side-slip angle and velocity are identified and estimated using a sliding mode observer. For this purpose and in order to insure the observability of the system, the model is decoupled in two parts. In the first part, longitudinal forces are identified using a second order sliding mode observer based on a modified super-twisting algorithm, while in the second part, vehicle velocity and side-slip angle are estimated using a classical sliding mode observer. Validations with the simulator VE-DYNA pointed out the good performance and the robustness of the proposed observers.