Tyre-road friction coefficient estimation based on the discrete-time extended Kalman filter

This paper presents a new algorithm for estimation of the instantaneous value and the maximum value of the tyre-road friction coefficient (the adhesion coefficient) depending on the quality of the road surface. The algorithm applies the discrete-time extended Kalman filter for state estimation. The underlying discrete-time non-linear state-space model was based on a two-wheel longitudinal vehicle dynamics model extended to include the scale factor parameter of the magic formula' for the longitudinal tyre force introduced by Pacejka. To verify the Kalman-filter-based algorithm, a validated real-time hardware-in-the-loop simulation environment was utilized, and the results were in agreement with the expectations.