Command Filter-Based Predefined-Time Adaptive Fuzzy Control for High-Order Nonlinear Interconnected Systems With Input Quantization

Abstract

This article focuses on studying an adaptive fuzzy predefined-time tracking control problem for uncertain high-order nonlinear interconnected systems with input quantization. The considered plants contain unknown nonlinear functions, quantized input signals, and external disturbances. Fuzzy logic systems (FLSs) are employed to estimate the unknown nonlinear functions, and by using its structural properties, the difficulty of designing the state variable functions is simplified. By employing adaptive backstepping recursive technique combined with power-based Lyapunov functions, the predefined-time control strategy is presented. Notably, a novel predefined-time filter is used to avoid repeated differentiation of virtual control functions. By applying predefined-time Lyapunov stability theory, the stability analysis demonstrates that all signals in the closed-loop systems remain bounded and the tracking error converges within a predefined settling time. Ultimately, a simulation example is provided to illustrate the validity of the proposed control strategy.