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With the aid of disturbance observer strategy, this article aims to investigate the disturbance rejection and stabilization problems for periodic piecewise time-varying systems that are subject to time-varying delays, parameter uncertainties, nonlinear perturbations and exogenous disturbances. To be more specific, the periodic piecewise time-varying systems are built by segmenting the fundamental period of periodic systems into a limited number of subintervals. Further, the disturbances engendered from an exogenous system are estimated by deploying the disturbance observer and subsequently, on the premise of disturbance that is esimated, a robust controller protocol is constructed for the considered system. Moreover, by bridging the time-varying periodic piecewise Lyapunov-Krasovskii functional with a matrix polynomial lemma, a set of adequate criteria is framed, which confirms the asymptotic stability of the system that is being addressed. Subsequently, on the premise of established criteria, the design of periodic piecewise gain matrices of devised controller and configured observer are presented. Eventually, the importance and potential of the presented theoretical concepts are evidenced through offering a numerical illustration with the simulation results.

In this paper, the design of a disturbance rejection-based fuzzy quantized resilient control for T-S fuzzy chaotic systems with randomly occurring parameter uncertainties and external disturbances is discussed. Specifically, a disturbance rejection technique is adopted in order to estimate the external disturbances with high precision that are impacting the system. Subsequently, by including a logarithmic quantizer into the feedback control, the control signals are quantized. From thereon, the estimated disturbance is fed into the quantized control path to counteract the impacts of disturbances on the system with an intent to achieve intended performance of the system. Moreover, through the utilisation of Lyapunov’s stability theory, adequate criteria affirming the stabilization of the undertaken system are procured in the form of linear matrix inequalities. On the basis of specified criteria, the design procedure of controller and observer gain matrices are presented. In the end, numerical examples together with the results of simulations are laid out so as to corroborate the relevance and effectiveness of the developed techniques.