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In this work, the input–output finite-time stability (IO-FTS) of a class of continuous-time switched systems characterized by uncertainties and subjected to external disturbances is studied under asynchronous switching by means of the sliding mode control (SMC) method. The IO-FTS poses a finite-time constraint problem, which involves addressing two main issues: firstly, ensuring that the state trajectory of the switched system reaches the given sliding mode surface within the specified time, and secondly, achieving IO-FTS for the closed-loop switched system during asynchronous switching. To address these issues, we apply a partitioning strategy and construct asynchronous sliding mode controllers with adjustable parameters to ensure the reachability of the system's state trajectory within a finite time. Subsequently, we employ a multiple Lyapunov function (MLF) approach to provide sufficient conditions that ensure IO-FTS during the whole phase [ 0 , T ] for the resulting switched system. Additionally, we analyze the asynchronous characteristics concerning the reachability phase of the designed sliding surface, considering the system's switching properties. Finally, we demonstrate the efficacy of the proposed approach with a numerical example. [ABSTRACT FROM AUTHOR]

In this work, the sliding mode control (SMC) problem is investigated for a class of Lur'e nonlinear switched systems subject to finite channels constraints, which may lead to data collision. To solve this phenomenon, the Weighted Try-Once-Discard (WTOD) protocol is proposed on the sensor-to-controller (S/C) channels to regulate which one sensor node is permitted to send data via the communication network at each instant. A key issue of this work is how to integrate the WTOD protocol into the design of observer and the sliding mode controller for the switched systems. To this end, a token-dependent observer is constructed to estimate the unmeasured states, and then an observer-based SMC law is properly designed. Moreover, by constructing a Lur'e-type Lyapunov function interconnected with a cone-bounded nonlinearity, some sufficient conditions are established such that the reachability with a sliding domain around the specified sliding surface is achieved, meanwhile, the exponential stability of the resultant closed-loop switched systems is guaranteed. Finally, some numerical simulation results are provided. [ABSTRACT FROM AUTHOR]

Summary: This article focuses on the sliding mode control of a class of interval type‐2 fuzzy systems with immeasurable states. During the data transmission from the sensor to the controller, the intermittent denial‐of‐service (DoS) attacks may be launched by vicious opponents. A key issue is to evaluate the tolerable region of the attacks for keeping the desired dynamic performance of the controlled interval type‐2 fuzzy systems. To this end, two weighting coefficients are first introduced to construct new membership functions. Based on this, a switched interval type‐2 fuzzy estimator is proposed to estimate the immeasurable state and compensate for the lost measurements caused by DoS attacks. And then, considering different DoS statues, a switched sliding mode controller transiting between the attack free and active cases is synthesized such that the specified sliding surface can be reached. In addition, the acceptable DoS region is quantitatively analyzed via a switched Lyapunov function. It is proven that the input‐to‐state stability of the sliding mode dynamics and the error system can be ensured within this tolerable DoS region. Finally, a simulation example is provided to illustrate the proposed control scheme. [ABSTRACT FROM AUTHOR]

Summary: This work considers the sliding mode control problem of a class of discrete‐time uncertain switched systems subject to detecting‐delay on mode signals, which may result in the asynchronous phenomenon between the controller and the switched system. Since the mode information of the controlled system is not available for the controller in time, a mode‐independent sliding surface will be introduced, by which an asynchronous sliding mode controller is designed, whose control gain and robust parameter will be changing according to the controller mode. In the analysis on the stability of the closed‐loop control system and the reachability of the specified sliding surface, the asynchronous characteristics are detailedly investigated. It is shown that the Lyapunov function may be not always decreasing along the state trajectories during the unmatched interval of controller modes and system modes. Nevertheless, it is proven that the state trajectories can be driven into a sliding region around the specified sliding surface in finite time. Finally, some numerical simulation results are provided. [ABSTRACT FROM AUTHOR]

The problem of sliding mode control (SMC) is investigated for a class of uncertain switched systems subject to unmeasurable state and assigned finite (possible short) time constraint. A key issue is how to ensure the finite-time boundedness (FTB) of system state during reaching phase and sliding motion phase. To this end, a state observer is constructed to estimate the unmeasured states. And then, a state estimate-based SMC law is designed such that the state trajectories can be driven onto the specified integral sliding surface during the assigned finite time interval. By means of partitioning strategy, the corresponding FTB over reaching phase and sliding motion phase are guaranteed and the sufficient conditions are derived via average dwell time technique. Finally, an illustrative example is given to illustrate the proposed method. [ABSTRACT FROM AUTHOR]