Filter‐based robust model‐free adaptive funnel control for discrete‐time nonlinear systems with jumped reference signal

Abstract

This article proposes a filter‐based robust model‐free adaptive funnel control for discrete‐time nonlinear systems with measurement noise and jumped reference signal. To suppress the effects of measurement noise on the estimated dynamic linearized model, a robust projection algorithm with filtered output is designed to estimate the pseudo‐partial derivative vector. Based on this estimated model, a novel discrete‐time funnel function‐based switching sliding‐mode surface is proposed to cope with the problem of the jumped reference signal. A time‐varying weighting factor‐based cost function is proposed in the controller design to reduce the control consumption whenever the tracking error exceeds the actual performance funnel, and the time‐varying weighting factor is tuned by a designed event‐triggered mechanism. Furthermore, the performance margin, tolerable uncertainties, and parameter selections have been analyzed in detail. Simulations and experimental results verify the effectiveness of the proposed robust control strategy.