Adaptive Observers and Estimation of the Road Profile

In this paper, we present an adaptive observer to estimate the unknown parameters of a vehicle. The system unknown inputs, representing the road profile variations, are estimated using sliding mode observers. First, we present some results related to the validation of a full car modelization, by means of comparisons between simulations results and experimental measurements (coming from a Peugeot 406 as a test car). Because, we don't know exactly pneumatic parameters and because these parameters can be changed, an other sliding mode observer is developed to estimate the longitudinal forces (which depend on these parameters) acting on the wheels. The estimated Road Profile is compared to the measured one coming from the LPA (longitudinal profile analyser ) in order to test the robustness of our approach.