Jumei Wei

This article investigates the design problem of periodic event-triggered quantized control (PETQC) for general nonlinear networked control systems (NCSs) with multiple communication channels between the plant and the controller. The transmission of information over these channels is asynchronous, and the transmission instants are determined by a local dynamic event-triggering mechanism (ETM). In each channel, continuous signals are sampled and quantized with a dynamic quantizer (DQ) before being transmitted due to limited bandwidth. In addition, large transmission delays may occur, and packets may be lost even without acknowledgments. To tackle these challenges, we introduce auxiliary variables and design appropriate jump rules to monitor the changing process of the total network-induced errors. Meanwhile, we propose new design conditions for ETM and DQs, and develop an encoding rule and a decoding algorithm. Then, we construct a new Lyapunov function and design a PETQC strategy to ensure the input-to-state stability of the nonlinear NCSs. Next, we construct triggering functions and dynamic variables for the event trigger in each channel. Compared with the existing literature, the proposed design conditions for periodic ETM involve fewer constraints and are less conservative. Finally, the efficiency and less conservatism of the theoretical results are illustrated by simulation studies.

The stability analysis of networked switched systems becomes highly challenging when multiple factors—such as frequent switching, denial-of-service (DoS) attacks, transmission delays, and actuator faults—coexist under an event-triggered mechanism (ETM). These intertwined factors cause complex timing mismatches that invalidate most synchronization-based control frameworks. To address this challenge, this article proposes a resilient event-triggered fault-tolerant control strategy that captures multisource asynchrony by classifying multiple key instants and modeling their interactions through a Lyapunov-based scheme. Unlike most existing studies that rely on synchronized switching assumptions or oversimplify the timing structure by ignoring delays and DoS attacks, this work explicitly incorporates these asynchronous phenomena into a unified analytical framework. First, to ensure timely packet transmission, a hybrid ETM is designed by combining time-triggering and event-triggering conditions. A switched Lyapunov function is then constructed by classifying different intervals, thereby unifying the analysis of asynchronous behaviors and DoS-induced disruptions. Furthermore, a resilient codesign strategy is developed, where the event-triggered parameters and fault-tolerant control gains are jointly designed under an explicit trade-off among the average dwell time parameter of switching signals, DoS attack parameters, and the sampling period. Under the proposed framework, global exponential stability with $H_{\infty } $ performance is guaranteed despite the presence of transmission delays, actuator faults, and DoS attacks. Finally, the effectiveness of the proposed method is demonstrated using a quarter-vehicle suspension system.

Event-triggered control (ETC) has been proposed in the networked control systems (NCSs) literature to reduce the need of data transmissions, and the main focus has been on the design of ETC mechanisms with a guaranteed positive minimum of inter-event time (MIET) and hence avoiding Zeno phenomena. In this paper, we propose a design of an aperiodic ETC mechanism for general nonlinear NCSs. In our setup, the communication network could introduce variable transmission delays, while data packets could get lost without acknowledgements. For this, we first introduce auxiliary variables dependent upon the transmission situations to capture the relationship between the number of successive packet dropouts, MIETs, transmission delays and the number of successful packets being transmitted. Meanwhile, by designing appropriate jump rules of these variables, the changing process of the network-induced errors can be tracked. Then, we present a novel output-based dynamic ETC strategy that can simultaneously guarantee a finite $L_{p}$ -gain and a strictly positive lower bound despite the presence of packet losses and transmission delays. In particular, the mandatory limit of short delays can be avoided, and the transmission delays exceeding the positive MIETs are allowed. Finally, a numerical example is given to verify the correctness and effectiveness of the proposed control approach.

Event‐triggered controllers are designed for cyber‐physical systems (CPSs) with multiple transmission channels in this article, including two cases: with and without denial‐of‐service (DoS) attacks. Through the design of switching controller and the use of linear matrix inequality‐based (LMI‐based) method, the global exponential stability of the CPSs with multiple transmission channels in both cases are proved, and the relationship of parameters of DoS frequency and duration with the sampling period is established. An example of unmanned ground vehicle under DoS attacks is given to show the effectiveness of the proposed control method.

This paper proposes a singular system-based approach for active vibration control of vehicle seat suspensions, where the drivers' acceleration is augmented into the conventional seat suspension model together with seat suspension deflection and relative velocity as system states to make the suspension model as a singular system. In this novel seat suspension system, all the system states are easy to measure in real-time. A friction observer is applied to estimate the real system friction and an H∞ controller is designed to achieve the optimal ride comfort performance with consideration of the friction compensation, actuator saturation, and time delay issues. The cone complementarity linearization (CCL) algorithm is applied to solve the nonlinear constraints. The experimental results show that good ride comfort performance can be achieved by the proposed controller in both the time and frequency domain compared with the uncontrolled seat suspension.

This paper addresses the finite-time stability problem of linear switched singular systems with finite-time unstable subsystems. Dynamic decomposition techniques are used to transform such systems into equivalent one that is a reduced-order switched normal systems. Based on the mode-dependent average dwell time (MDADT) switching signal, new sufficient conditions are presented to guarantee the linear switched singular systems with finite-time unstable subsystems being finite-time stability, finite-time bounded and finite-time stabilization. Finally, a numerical example is employed to verify the efficiency of the preceding method.