On Explicit Tuning Laws of Active Disturbance Rejection Control for Nonlinear Uncertain Systems Under Quantized Sampled‐Data Measurements

ABSTRACT In this paper, the control problem for a class of systems with nonlinear uncertain dynamics under quantized sampled‐data measurements is considered. Firstly, the explicit tuning laws for ADRC design with a discrete ESO for promptly estimating the total disturbance are presented to tackle the control problem of nonlinear uncertain systems under quantized sampled‐data measurements. Moreover, a feasible set of the ESO's bandwidth is given to ensure the stability of the closed‐loop nonlinear system despite various disturbances. Secondly, the performance of ADRC under quantized sampled‐data measurements is rigorously analyzed. It is discovered that the tracking error between the system state vectors and the desired trajectory can converge to a desired bound by tuning the bandwidth of ESO, the sampling step, and the quantizing step together. Finally, the necessary and sufficient condition for the tracking error to be infinitesimally equivalent to the sampling step and quantizing step is discussed, and the proposed method is tested on a numerical simulation concerning aircraft longitudinal overload control. The simulation results thoroughly demonstrate the competence of our tuning laws.