A novel estimation scheme of tyre–road friction characteristics based on parameter constraints on varied-µ roads

Abstract

On varied-µ roads, most of the current research on the estimation of tyre-road characteristic parameters and peak friction coefficient lack consideration of parameter constraints. To improve the estimation accuracy, in this study, a novel estimation scheme of tyre-road friction characteristics based on parameter constraints is proposed: based on estimating the longitudinal and lateral friction force, a data preprocessing method is proposed to obtain the constraint region of parameters. Then, the nonlinear least square method is used to preliminarily estimate the parameters. Finally, a constrained auxiliary particle filter algorithm is proposed to correct the estimated parameters. To verify the superiority of the proposed scheme, the estimation performances of friction characteristics of four schemes are compared on low/high speed varied-µ roads, respectively. The results demonstrate that the proposed scheme has the best estimation performance. Simultaneously, compared with the scheme without considering parameter constraints, the proposed scheme can significantly reduce the estimation error.