Estimation of the maximum friction coefficient for a passenger vehicle using the instantaneous cornering stiffness

The estimation of the maximum lateral coefficient of friction of a passenger vehicle between tire and road is presented in this paper. This is achieved by utilizing the instantaneous cornering stiffness, which is defined as the slope of the nonlinear curve of the lateral friction coefficient at the instantaneous tire slip angle. The maximum lateral coefficient of friction is necessary for integrated global cassis control (IGCC) especially for the estimation of the lateral velocity of the vehicle. The advantage of this method is the low computational effort and the independence of tire or road conditions. Two methods for estimation of the instantaneous cornering stiffness and the maximum coefficient of friction in real time and a method for offline estimation used as a reference are described and validated using measured data of a passenger vehicle.