Lateral Control for UGVs by ADRC With Modeling Compensation and Expanded Disturbance Observation

By improving observer estimation accuracy, an active disturbance rejection control (ADRC) strategy is proposed for an unmanned ground vehicle (UGV), where dynamic performance is enhanced by disturbance suppression during trajectory tracking. In the strategy, part information of the lateral control model is added to the state matrix, so as to compensate estimation bias of UGV states from an extended state observer (ESO). Then, a free variable for estimating higher-order disturbance states is integrated into the highest-order variable of the ESO, and ESO accuracy is thus improved for total disturbance estimation. To achieve accurate suppression of complex disturbance, estimates of UGV total disturbance are added to the control law according to feedback linearization theories. System stability is proved by theoretical analysis, and estimation accuracy for system states and total disturbance are enhanced by above improvement. Finally, comparative tests are conducted under multiple cases to verify the performance of the proposed strategy.