The control of high-clearance electric vehicles based on pavement parameter estimations

Agricultural high-clearance vehicles are different from traditional vehicles. Agricultural vehicles have particular features that are mainly suited for the agricultural vehicle’s working environment. Farmland is relatively complex, mostly unknown and unstructured environment, and it is difficult to accurately model. The complex characteristics of farmland or hilly terrain demands that the agricultural machinery on the ground environment must have sufficient robustness. In this article, a soft road high vacant land vehicle model is established, and then, through the observation of force of tyres and the use of an existing tyre model recursive least square parameter estimation, the road adhesion coefficient is obtained. Considering that the sliding mode control can effectively solve the parameter uncertain nonlinear system, the model established herein has the advantages of robustness and fast response. The sliding mode control and the incremental proportional–integral control were used to test the uniform pavement and the separate pavement, respectively, and the results showed that the sliding mode control was closer to the target value than the incremental proportional–integral control but was less stable than the incremental proportional–integral control on the uniform road surface; in addition, the sliding mode control was superior to the incremental proportional–integral control on the separate road surface.