In this article, we investigate a Euclidean-distance-based distributed constrained optimal formation matching (EDCOFM) problem for open large-scale multiagent systems (OLSMASs), where the number of agents is large and variable. To address the open property of the multiagent system, we introduce the concept of a depository, which can provide additional agents or store redundant agents. When the number of agents is sufficient to achieve the formation configuration, a distributed formation matching algorithm for a large-scale multiagent system (DFMA-LSMAS) is proposed to search for the optimal location of the formation configuration within a designed constraint and the optimal matching relationship. Notably, the framework is applicable to open multiagent systems. When the number of agents is smaller than the requirement to achieve the formation configuration, and more than one agent needs to be provided from the depository, an unmatched phenomenon occurs, which results in the failure of the proposed algorithm. To address this, a disturbance-based approach is proposed to eliminate the phenomenon without impacting the optimal solution. When the number of agents is larger than the requirement to achieve the formation configuration, and some agents have to leave the system, a fair competition mechanism is proposed to selectthe remainder and their optimal matching relationship. This mechanism avoids multiple competitions in a centralized manner. Finally, several simulation results are provided to verify the proposed algorithms.

Cooperative adaptive cruise control (CACC) systems face critical cybersecurity challenges due to vulnerabilities in vehicle-to-vehicle (V2V) networks and onboard sensors. Covert attacks have become a critical research focus in CACC systems due to their inherent risks and stealthiness. In this article, a novel attack model called covert coordinated attack (CCA) is proposed, and its detection and isolation schemes are proposed to enhance the resilience of CACC systems against such an attack. First, the specific CCA strategies are proposed by revealing dual-channel attack coordination mechanisms targeting both sensors and V2V networks. Second, the detection framework based on unknown input observers (UIOs) is designed by monitoring the residual-based health characteristic. Third, based on the established two auxiliary systems, an attack isolation strategy integrating UIOs and extended state observers (ESOs) is proposed for attack reconstruction and system performance recovery. Finally, numerical simulations are conducted to validate both the stealthiness of CCA and the effectiveness of the proposed attack detection and isolation methods.

This article addresses an enhanced distributed outlier-resilient fusion estimation problem using an interval type-2 (IT-2) Takagi–Sugeno (T–S) fuzzy model, integrating outlier detection schemes and dimensionality reduction (DR) strategies. First, the IT-2 T–S fuzzy model is employed to handle system uncertainty and nonlinearity effectively. Then, the outlier-resilient local estimator is proposed using the zonotope-based set-membership filters (ZSMFs), where the outlier detection scheme only relies on the intersection between the predicted set and the measurement set. Furthermore, the compressed local estimate (LE) are designed when there are bandwidth constraints in sensor networks, and a novel DR strategy is proposed to design this compressed LE, where the compression matrix is determined by the Round–Robin protocol (RRP). After this, based on the compressed LEs, a distributed resilient zonotopic fusion estimator (DRZFE) is derived by the matrix-weighted fusion method. Note that the computational load of the DRZFE is reduced effectively due to the zonotope order reduction and the RRP-based DR independent of the online optimization. Moreover, the compensation of outliers and the compensating state estimate of RRP-based DR may improve the resilience of the algorithm and reduce information loss. Finally, two numerical examples are provided to validate the advantages and effectiveness of the proposed methods, and we use root-mean-square-error as the indicator to assess the estimation accuracy.

Accurate state of charge (SOC) is crucial to achieving safe, reliable, and efficient use of batteries. This article proposes an adaptive neural network (NN)-based event-triggered observer to estimate SOC. First, a stochastic battery equivalent circuit model (ECM) is established, where an adaptive NN is employed to approximate the unknown nonlinear part. The learning process of network weight is conducted online to observe the variations of model parameters and avoid time-consuming processes for parameter extraction. Besides, for the purpose of saving computational cost, an event-triggered mechanism (ETM) is employed in the weight updating law, which means the weights only update when it is necessary. Then, an adaptive radial basis function (RBF) NN-based SOC observer is designed, and its stability is proven by the Lyapunov theory. Moreover, the strictly positive lower bound of interevent time is derived, and undesirable Zeno behavior can be excluded. Finally, the accuracy and robustness of the proposed observer are evaluated by experiments and simulations. Results show that the proposed method can estimate SOC accurately in the presence of initial deviation and sensor noises.

This article studies the impact of constrained optimal stealthy attacks on the state estimator, where man-in-the-middle attacks with a linear form can compromise innovations transmitted through a wireless network. First, a novel resource-constrained attack model is proposed, in which there are only a finite number of attack instants within a fixed interval. Second, the evolution of the estimation error covariance under attacks is obtained, and the covariance at the ultimate instant of the attack interval is regarded as the attacker’s cost function. Moreover, a relaxed condition of the strict stealthiness, named Kullback–Leibler divergence, is employed to describe the attacker’s the stealthiness metric. Third, the one-time and holistic optimization problems of stealthy attacks are solved by exploiting the Lagrange multiplier method. Then the constrained optimal attack strategies are obtained to produce the largest ultimate estimation error covariance. Finally, two simulation cases are provided to confirm the correctness of the designed attack strategies.

Nowadays, human-oriented has already become the direction of the development of the intelligent vehicle, among which, the cabin, in constant contact with drivers, is getting more and more attention. Intelligent assisted systems have alleviated the burden on drivers during long journeys and provided a remedy for operational errors. As the trend towards increasingly intelligent vehicles, the issue of human-machine co-driving is receiving attention from scientific researchers. The technologies of human-machine interactions usually contain two parts, the human-to-vehicle and vehicle-to-human. This paper analyzes the potential innovation of human-machine systems from the perspective of human sensing, including visual, auditory, tactile, and olfactory. Based on the review of human-machine technologies, the current intelligentization of vehicles is divided into driver interaction and crew service systems. Then, the structure of a future intelligent interaction system considering multi-sensing is proposed and further discussed. Finally, by analyzing the relationship between the system for human and autonomous systems, a classification of the intelligence level for interaction systems is presented.

This article deals with the fully distributed pull-based event-triggered bipartite fixed-time output consensus problem of heterogeneous linear multiagent systems (HLMASs) with an active leader, whose information can be merely accessed by a small fraction of followers. First, a class of fully distributed fixed-time observers is proposed for each follower to estimate the leader's system matrices, position, and control input under the signed communication topology, respectively. Then, based on the estimations of leader's system matrices, two adaptive algorithms are given to solve the regulator equations. Furthermore, the fully distributed fixed-time observer-based controllers associated with state feedback and output feedback are, respectively, proposed by employing the pull-based event-triggered mechanism (ETM) where each agent merely updates controller at its own triggering instants. Correspondingly, some sufficient criteria and the rigorous proofs are provided to ensure the implementation of bipartite output consensus in fixed time by using the Lyapunov stability theory and fixed-time stability theory. Moreover, the strictly positive lower bounds of intervals between two adjacent event-triggered times are derived, which means the Zeno behavior is ruled out. Finally, numerical simulations are performed to demonstrate the theoretical analysis.

Accurate state of charge (SOC) can effectively improve safety performance and prolong the cycle life of the batteries. The widely used model-based SOC estimation methods have underlying assumptions of complete measurements and accurate estimator gains, which are not always reasonable in practical applications. Thus, this article designs a dual Kalman filter-type resilient filter to estimate SOC and parameter jointly with the random missing measurement phenomenon which is modeled by a Bernoulli distributed sequence. Besides, the filter gain variations, in both online parameter identification and state estimation, are characterized by mutually independent multiplicative noise terms. Then, based on the minimum-variance principle, the filter gains are designed to minimize the effects of the missing measurement and gain variations on the estimation performance. Finally, extensive simulations and experiments are conducted to validate the effectiveness and resilience of the proposed method.

This article deals with the fully distributed dual-terminal dynamic event-triggered bipartite output containment control of heterogeneous linear multiagent systems (HLMASs) subject to actuator faults. First, a class of fully distributed dynamic event-triggered observers is proposed over the directed signed communication network for each follower to estimate the leaders’ system matrices and (symmetric) combination states, which are merely available to a small fraction of followers. Then, based on the estimations of leaders’ system matrices, adaptive algorithms are employed to solve the regulator equations. Furthermore, the fully distributed observer-based dynamic event-triggered controllers are proposed by integrating the adaptive gains to compensate for actuator faults. Dual-terminal dynamic event-triggered mechanisms (ETMs) are addressed to exclude not only continuous control updates but also continuous communication among agents. Correspondingly, some mild criteria and the rigorous proofs are established to ensure the implementation of bipartite output containment through the Lyapunov stability theory. Moreover, the strictly positive lower bounds of intervals between two adjacent event-triggered time instants are derived, which indicates that Zeno behavior is ruled out in the dual-terminal dynamic ETMs. Finally, numerical simulations are performed to demonstrate the theoretical analysis.

The fully distributed consensus tracking of stochastic nonlinear multiagent systems (MASs) is investigated with Markovian switching topologies and intermittent control strategy, where the dynamics of agents are depicted by Itô differential equations and the leader’s information is just known for a fraction of followers. The switching mechanism of interaction topologies is modeled as a Markov process. A novel class of fully distributed control protocols is proposed via intermittent control method, which is only associated with the relative state measurements of neighbors and does not involve any global information. Meanwhile, the control gains are designed to be intermittently adaptive, which can effectively reduce energy consumption and avoid the gains being larger than those needed in practice. Several sufficient conditions and corresponding proofs are provided by using the Lyapunov stability theory. Finally, numerical simulation is presented to state the feasibility of the theoretical results.

In this article, the containment control problem of multiagent systems (MASs) with active leaders under a directed communication graph is addressed. A novel pull-based event-triggered protocol combined with aperiodic sampled-data mechanism is first presented, where each agent merely updates controller at its own triggering instants. Under the proposed control protocols, the information is only exchanged and calculated at the aperiodic sampling instants, therefore, it can reduce communication congestion and save computing resources. Furthermore, the Zeno behavior is naturally excluded because the trigger instants are in the set of aperiodic sampled instants. By virtue of the algebraic graph theory and Lyapunov stability analysis, it is shown that the active leaders can reach their desired states predefined arbitrarily and all followers are driven to the convex hull formed by the leaders. Finally, an illustrative example is given to validate the theoretical results and emphasize the advantages of the proposed protocols.

The group consensus problem for fractional-order multiagent systems is investigated in this paper. With the help of double-tree-form transformations, the group consensus problem of fractional-order multiagent systems is proved to be equivalent to the asymptotical stability problem of reduced-order error systems. A class of distributed control protocols and some simple LMI sufficient conditions as well as necessary and sufficient conditions are proposed in this paper to solve the group consensus problem for fractional multiagent systems. Moreover, pinning control strategy has been taken into consideration. It is shown that the system converges more rapidly when the designed pinning protocols are adopted. In addition, the case of fractional system with switching topologies is also discussed and some corresponding sufficient conditions are obtained. Finally, some simulation results are presented to illustrate the theoretical results.

This paper investigates the event-triggered consensus of linear multiagent systems with periodic data sampling mechanisms, where random packet losses are taken into account. The random packet losses occur in communication links based on a certain probability, and it is subject to the Bernoulli distribution. A novel distributed control protocol is designed based on the combined measurement to achieve the mean square consensus. By using the Riccati inequalities and linear matrix inequalities, an event-triggered condition with fewer parameters is also designed to reduce the information updating number. The interaction among the control gain matrix, sampling interval, and packet losses probability is used to describe the consensus conditions. The maximum sampling interval is presented explicitly. It is shown that the advantages of the proposed event-triggered strategy with the data sampling mechanism can avoid the Zeno behavior of the systems and continuous monitoring of the states. The simulations are provided to verify the proposed control strategy.