Abstract:
It is difficult for unmanned ground vehicle (UGV) to maintain good dynamic performance in complex external environments. For this problem, a bias rectification-based cascaded active disturbance rejection control (ADRC) strategy is proposed, which enhances the disturbance suppression performance of UGV control system by improving disturbance estimation accuracy of the observer. Firstly, generalized external disturbance and system internal disturbance are reconstructed as total disturbance, and rectification items are set to expand observation order of the primary disturbance observer. Then, residual disturbance unobserved in time is estimated in the secondary disturbance observer, to improve the observation accuracy. Based on feedback linearization theories, a trajectory tracking control law containing total disturbance estimation is designed, so as to improve the tracking error convergence speed and tracking accuracy of UGV. To improve controller adaptability to different UGV models, a parameter configuration strategy is designed according to correspondence between controller key parameters and the closed-loop model. Stability and anti-disturbance performance of the UGV system are demonstrated by theoretical analysis, and comparative experiments are conducted to test the performance of the proposed control method in various situations. The experimental results show that the proposed strategy can effectively improve the trajectory tracking effect of UGV in uncertain environments.