Torques and tyre forces observation by intelligent sensors: case of longitudinal vehicle dynamics

Abstract

The knowledge of individual torques at each wheel are important intermediate variables for the design of advanced driver assistance systems. A nonlinear high-gain unknown inputs state observer is designed to compute simultaneously longitudinal and vertical tyre forces, resultant torques applied to wheels, and the vehicle speeds with a very simple four wheels model. The necessary measurements are the usual rotation speed of each wheel. Successful simulated experimentations of the method are shown as well as its present limits.