This work studies the problem of data-driven event-triggered control of continuous-time multiagent systems (MASs) with communication delays. A hybrid system approach is proposed to address this problem, hybrid dynamic event-triggering mechanism (DETM) is utilized to ensure strong Zeno-freeness and estimated system matrix is introduced to design time-varying state estimator. By using several auxiliary variables, the closed-loop MAS is described into hybrid system form, that can completely describe the flow dynamics and jump dynamics of the MAS in the presence of communication delays. Then, data-based controller gain matrix design is developed and an estimator is designed to estimate unknown system matrix. After that, based on derived model-based stability conditions and combined with data-driven representation of MAS, data-based stability analysis and event-triggering mechanism (ETM) design results are obtained. The main advantages of the proposed approach in contrast with existing works are that accurate system model is not needed and strong Zeno-freeness is ensured under the scenario with communication delays. Finally, the effectiveness of the proposed method is verified by simulation example.

This paper investigates the consensus problem of multi-agent systems (MAS) subject to denial-of-service (DoS) attacks and actuator faults. For the aim of decreasing the communication frequency among agents, we first design a novel double-layer event-triggering mechanism (DLETM) with inherently joint characteristic1, the first layer ETM only works inside an agent and serves second layer ETM, and network information transmission is activated by the second layer ETM. In addition, resilient triggering conditions related to DoS attack status are constructed. Then, an iterative observer is developed to estimate the actuator faults, it is formally shown that the estimation errors converge as iteration number increases. For consensus analysis and DLETM design, a novel Lyapunov function with inverse trigonometric function is constructed to overcome the limitation of existing Lyapunov function, based on which, sufficient stability conditions are provided for the MAS under DoS attacks and faults. Finally, we verify the performance of the proposed approach using a simulation example.

This article focuses on the fully distributed dual-event triggered leader-following consensus problem of heterogeneous multiagent systems (MASs) with unknown leader input and actuator fault. A hierarchical triggered control framework is developed for the MASs. First, in the upper network layer, event-triggered observers are designed to reconstruct the leader’s information by using the states exchanged intermittently among the neighboring observers. Then, in the lower physical layer, an adaptive fault-tolerant controller is designed, whose update instant can be directly computed based on the received upper layer information. This not only has the potential to further reduce the update frequency of controller, but also avoid the continuous monitoring on measurement errors. Besides, utilizing this control framework can prevent the faults from being propagated along the communication network. Finally, a numerical example is provided to verify the effectiveness of theoretical results.

This paper develops a novel hybrid system approach to address the event-triggered stabilization problem of largescale T-S fuzzy systems subject to variable long transmission delays. Various changing behaviours of deviation errors caused by transmission delays, as well as the changes of some auxiliary variables are modeled by a hybrid dynamical system with flow dynamics and jump dynamics. Then, under the hybrid control framework, an observer based anti-disturbance controller and a delay-independent hybrid event-triggering mechanism (HETM) are proposed to stabilize the closed-loop system, while guaranteeing desired performance in disturbance attenuation and delay tolerance. Compared with the case that small transmission delays could naturally lead to delay-independent HETM, the long transmission delays pose many difficulties. Given this, we propose a more robust triggering condition with only using several memorized previous states to guarantee the HETM to be delay-independent even in case with long transmission delays. Moreover, the obtained stability conditions avoid involving lower and upper bounds of transmission delays in matrix inequalities, thus can be delay-independent and significantly simplified. Relationships between system stability and maximally allowable transmission delay are transformed to designing proper auxiliary functions offline. Finally, the effectiveness of proposed control protocol is demonstrated by a numerical example.

This work studies event-triggered bipartite consensus problem of multi-agent systems (MAS) with structurally balanced signed graph. A hybrid system approach is proposed to deal with the leaderless and leader-following bipartite consensus problems in a unified framework, and a novel hybrid event-triggering mechanism (ETM) is proposed to reduce the usage of communication resources. By appropriately defining closed-loop states, a unified hybrid model is constructed for both leaderless and leader-following MAS. Then, stability analysis and ETM design results are given under hybrid systems framework. It is worth noting that the designed hybrid ETM is in decentralized form rather than distributed form. Moreover, the lower bound of triggering intervals can be pre-selected, i.e., Zeno-freeness is guaranteed, that is important for control implementation. The proposed method is applied to satellite formation system in simulation results to show the effectiveness.Note to Practitioners—This paper considers bipartite consensus control problem of MAS, which can be applied to some practical systems, e.g., bidirectional formation of unmanned air vehicles, since the control objective in these applications can be transformed into bipartite consensus control problem of MAS. Compared with the existing results, a hybrid system approach is proposed for consensus analysis of MAS with or without leader, and a novel event-triggering mechanism is proposed, which is more easier to be implemented, so, the proposed approach is more friendly for control engineers. The obtained results are applied to satellite formation control problem and the effectiveness is verified, and it is expected that the proposed approach can be extended to MAS with more realistic network-induced constraints and applied to more practical engineering systems.

This article investigates the secondary control problem of islanded microgrid under hybrid systems framework. Owing to network-induced imperfections caused by communication and limited communication resources, we consider the event-triggered secondary control problem under time-varying delays. A hybrid dynamic event-triggering mechanism (ETM) (DETM) is proposed to reduce the usage of communication resources, the event triggering interval is enforced to be lower bounded by strictly positive value. A hybrid closed-loop model is constructed that incorporates the communication delays and ETM, and it facilitates stability and performance analysis. Lyapunov-based stability conditions are proposed, while the maximum allowable delay can be determined. Moreover, the proposed hybrid DETM ensures that the minimum event-triggering interval can be designable and prespecified, even in the presence of disturbances, which is important for control implementation. Finally, the effectiveness of the proposed control strategy is illustrated by simulation examples.

This article studies the self-triggered consensus control problem for linear multiagent systems (MASs) with the aim of improving resources utilization efficiency, e.g., saving communication bandwidth and reducing node energy consumption. First, a distributed control protocol is designed and a novel decentralized dynamic self-triggering mechanism (DDSTM) is proposed, with which, each agent can not only compute its own next triggering instant but also is able to compute the neighbors’ next triggering instant. Then, a hybrid system model is constructed to completely describe the close-loop system with jump dynamics. Based on the hybrid model, Lyapunov conditions are derived for MAS consensus analysis. The proposed DDSTM can overcome some limitations of the existing distributed STMs in the sense of synchronously acquiring consensus error or uniquely determining triggering instants, moreover, it allows transceivers to be turned on only at triggering instants and enter into sleep mode at the rest time, such that node energy is efficiently saved. Preadjustable minimum triggering interval is imposed between any consecutive triggering events; thus, a minimum sleep period for transceivers is always guaranteed. Finally, a numerical example is presented to demonstrate the effectiveness of the proposed approach.

This article focuses on the leader-following consensus problem for a class of high-order uncertain nonlinear multiagent systems (MASs) subject to denial-of-service (DoS) attacks and actuator faults under the directed topology. To reduce the network communication bandwidth resource from the controller to the actuator and mitigate the adverse effect from DoS attacks, a novel event-triggered control strategy is proposed based on the reliable attack detection mechanism. The general attack detection mechanisms depend on the residuals between the values from the systems and observers. Different from the general attack detection mechanisms, a novel attack detection mechanism is proposed based on the logic relationship of voltage level signals which from the outputs of system components. Besides, the controller is designed based on the backstepping method and the controller can guarantee that the Zeno behavior is excluded. Furthermore, by using the Lyapunov stability theory, it proves that the controllers make the MASs achieve consensus. Eventually, a simulation example is presented to demonstrate the effectiveness of the proposed theoretical results.

Quiescent supply current (IDDQ) is a very effective test method for CMOS circuits. However, IDDQvector verification and debugging may take considerable time and effort; various problems have been encountered in this process, so different tools and methodologies have been devised to address them. For pre-silicon IDDQvector verification, a modular approach is adopted. IDDQis estimated for each vector based on leakage libraries of cells, and cell constraints can be verified automatically. For post-silicon IDDQvector issues, methods and analysis tools have been developed to identify the root causes. Scan cell and net value analysis will identify critical scan cells and nets, which will determine whether an IDDQpattern passes or fails, thus revealing the source of the extra leakage. These methodologies are proven to be very successful for IDDQvector debug and IDDQdiagnosis.