Hai-Tao Zhang

• PhD
• Professor (Full) at Huazhong University of Science and Technology

It has long posed a challenging task to optimally deploy multi-agent systems (MASs) to cooperatively coverage poriferous environments in real cooperative detection applications. In response to this challenge, this paper proposes a hierarchical coverage control (HCC) protocol for MASs to perform sector-based coverage operations. First, a distributed...

In this paper, a distributed algorithm is proposed to identify the node and edge numbers of anonymous leader-follower networks. The present distributed method works merely by exchanging scalar information by local intercommunication. The merit of the algorithm lies in identifying the required network parameters in time-varying topological networks...

In this note, a detective matrix-based distributed algorithm is proposed to address a distributed minimum-time consensus prediction problem for discrete-time high-order multi-agent systems (MASs). Therein, each agent predicts the consensus value merely using the minimum length of individual and/or neighboring successive position time series. Compar...

Periodical time-delay scenario is often encountered in industrial manufacturing processes. However, the presence of time delays and periodical coefficients brings challenges to controller design and system analysis, which thereby hinders the performance improvement of such systems. In this work, the dynamics of milling systems are transformed into...

This article addresses the flexible adaptive cooperative formation platoon control (ACFPC) of a fleet of underactuated autonomous surface vehicles (ASVs) suffered by environmental current and wind disturbances. A nonlinear vessel following strategy is constructed considering the inertia times of the ASVs through the utilization of a generalized loo...

In the previous Chaps. 2–7, we have conducted detailed research on two themes for the cooperative control of multi-robot systems, namely, “basic fencing” and “complex fencing.” However, the cooperative methods in these studies rely on the relative position between the robot and the target. However, such kind of information usually depends on distan...

In the past decades, the coordination of multi-robot systems has attracted a great deal of attention due to its low cost, high efficiency, large range, and strong robustness [1]. Technically speaking, the fundamental theory of the coordination of multi-robot systems is swarm intelligence, which was initially inspired by observing the common charact...

In this chapter, we summarize the whole monograph and further discuss future research topics of coordinated fencing missions.

In Chaps. 2 and 3, we have explored the themes of “basic fencing” and “complex fencing” with an evenly rotating formation based on the neighboring angle repulsion and input-to-state stability, respectively. Although Chaps. 2 and 3 addressed a moving target fencing and formation evolution, they only are applied to a constant-speed target. However, i...

The previous three Chaps. 3–5 focused on the theme of “complex fencing,” and successively proposed cooperative fencing controllers that are based on input-to-state stability, output regulation theory, and long-term task execution, respectively. Although they covered various functions such as target fencing, pattern regulation, and neighboring colli...

In the previous Chap. 6, we studied the multi-target fencing via adaptive controller, where the dynamics of the targets are always limited to cluster together. Such kind of scenario inevitably limits the application of the designed controller. A straightforward idea is to form a big circle of robots to fence the small circle formed by the target. H...

The previous Chaps. 3 and 4 introduced complex fencing with an evenly rotating formation and a varying-velocity target in 2D space, however, they still lack a formal method to develop the fencing control with general dynamics and even higher-dimensional Euclidean space. To this end, in this chapter, we propose a long-term task term algorithm (LTTE)...

In this chapter, we first consider the fundamental fencing problem for a constant-speed target under time-varying topologies. Although some previous works have addressed the fencing control of a constant-speed target, they are limited to solutions based on fixed topology or switching connected topologies, which are only effective in open and unobst...

In Chap. 2, we introduced a distributed fencing controller via neighboring angle repulsion to achieve cooperative fencing of a constant-speed target, establishing the fundamental task of fencing. This chapter considers the more complex fencing problem that ensures evenly rotational formation during the fencing process, which is distinct from the pr...

In this study, discrete-time high-order linear dynamics of multi-agent systems (MASs) is considered. A distributed minimal-time deadbeat consensus prediction (MDCP) algorithm is proposed that allows each agent to calculate the consensus value of an MAS merely by using the shortest intermittent information series of its own and its neighbors. The ch...

In this article, an optimal surrounding control algorithm is proposed for multiple unmanned surface vessels (USVs), in which actor-critic reinforcement learning (RL) is utilized to optimize the merging process. Specifically, the multiple-USV optimal surrounding control problem is first transformed into the Hamilton–Jacobi–Bellman (HJB) equation, wh...

This article addresses an affine-formation tracking control (AFTC) of underactuated autonomous surface vehicles (ASVs). A distributed observer is developed to estimate desired formation positions via an affine transformation. A trajectory tracking controller with prescribed-performance is designed to steer the ASV fleet with a time-varying formatio...

Data-based discovery of the underlying dynamics of nonlinear systems is of great importance to the prediction and control of engineering systems. This article presents a duplex neurodynamic learning (DNL) approach to the identification of discrete-time nonlinear systems subjected to both external disturbances and measurement noise. A neurodynamic l...

Learning dynamical networks based on time series of nodal states is of significant interest in systems science, computer science, and control engineering. Despite recent progress in network identification, most research focuses on static structures rather than switching ones. Therefore, this article develops a method for identifying the structures...

Identifying structures of complex networks based on time series of nodal data is of considerable interest and significance in many fields of science and engineering. This article presents a sparse Bayesian learning (SBL) method for identifying structures of community-bridge networks, where nodes are grouped to form communities connected via bridges...

This article presents a data-driven, Koopman operator-based modeling scheme for analyzing and predicting cross-coupling hysteresis effects of the piezoelectric tube scanners (PTSs) used in atomic force microscopes (AFMs). Such cross-coupling hysteresis effects between different PTS axes significantly reduce the positioning precision of AFMs. In con...

To extract the household attribute information from the large volume of smart meter data, this study proposes a resident characteristics estimator. Such an estimator enables energy suppliers to provide personalized services whereas to assist customers to reduce energy consumption. By leveraging the potential connections among different characterist...

Atrial fibrillation (AF), the most prevalent cardiac rhythm disorder, significantly increases hospitalization and health risks. Reverting from AF to sinus rhythm (SR) often requires intensive interventions. This study presents a deep-learning model capable of predicting the transition from SR to AF on average 30.8 min before the onset appears, with...

We design a distributed coordinated guiding vector field (CGVF) for a group of robots to achieve ordering-flexible motion coordination while maneuvering on a desired two-dimensional (2D) surface. The CGVF is characterized by three terms, i.e., a convergence term to drive the robots to converge to the desired surface, a propagation term to provide a...

In the sensor networks considered in this paper, the topology of agents aggregating neighbors’ data can be locally adjusted by each entity. In the sense of Fiedler value of network, this proper topological adjustment is easy to deploy and greatly benefits the increase of convergence rate in the tasks such as target localization, parameter estimatio...

Dear Editor, As a promising multi-agent systems (MASs) operation, autonomous interception has attracted more and more attentions in these years, where defenders prevent intruders from reaching destinations. So far, most of the relevant methods are applied in ideal environments without agent damages. As a remedy, this letter proposes a more realisti...

In this paper, an escaping-chasing control problem under triggered denial of service (DoS) attacks is addressed. A switching performance index-driven escaping-chasing path planning method is designed, and the tracking error systems are accordingly established. The analytical challenge lies in the tricky coupling between the performance index-driven...

Distributed networked systems with Laplacian dynamics play a crucial role in various fields such as engineering, biology, system science, social science and physics. To optimize the synchronization performance of such networks, topological adjustments have been identified as effective and efficient ways. This paper establishes a theoretical framewo...

In real maritime applications of autonomous surface vehicles (ASVs), the frequent occurrence of single propeller failure of catamaran ASVs is a common issue. In such a scenario, maintaining a stable ASV heading becomes challenging as just one propeller is operational. To address this issue, we propose a zigzag control strategy and thereby design a...

This article considers quadruped locomotion control in the presence of uncertainties. Two types of structured uncertainties are considered, namely, uncertain friction constraints and uncertain model dynamics. Then, a min-max optimization model is formulated based on robust optimization, and a robust min-max model predictive controller is proposed b...

It has long been a challenging task for multi-agent systems (MASs) to inexpensively service probable events in non-convex environments. Coverage control provides an efficient framework to address MAS deployment problem for optimizing the cost of tackling unknown events. By means of the divide-and-conquer methodology, this paper proposes a sectorial...

This article proposes a distributed guiding-vector-field (DGVF) controller for cross-domain unmanned systems (CDUSs) consisting of heterogeneous unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs), to achieve coordinated navigation whereas maneuvering along their prescribed paths. In particular, the DGVF controller provides a hiera...

The concept of network resilience has gained increasing attention in the last few decades owing to its great potential in strengthening and maintaining complex systems. From network-based approaches, researchers have explored resilience of real ecological systems comprising diverse types of interactions, such as mutualism, antagonist, and predation...

Exploring the mechanism of hysteresis dynamics may facilitate the analysis and controller design to alleviate detrimental effects. Conventional models, such as the Bouc-Wen and Preisach models consist of complicated nonlinear structures, limiting the applications of hysteresis systems for high-speed and high-precision positioning, detection, execut...

This paper addresses an event-triggered output synchronization problem of linear heterogeneous multi-agent systems (MASs) under directed graphs, where only the outputs not the internal information of the agents are allowed to be transmitted in the network. The event-triggered output synchronization problem is divided into two subproblems, the event...

In this article, the consensus of constrained linear heterogeneous multiagent systems under prediction and optimization is investigated. By optimizing the consensus problems constrained to state equations and general linear constraints, two types of distributed analytical model predictive controllers are proposed. Furthermore, stability conditions...

This work studies the scaled consensus problems of exponentially unstable networked systems with time-varying input delays. First, a distributed consensus algorithm is designed under the truncated predictor feedback technique. Then, a delay bound is evaluated by utilizing the Lyapunov function-based method. Moreover, the consensus can be guaranteed...

Imbalanced vibration is an urgent yet challenging problem in active magnetic bearings (AMBs) rotor manufacturing due to the rotor mass imbalance effect. The virtue of active control in AMB systems lies in enabling substantial online mitigation of imbalanced vibrations. However, in practice, due to the lack of speed sensors in most of the existing A...

In this paper, a Hankel matrix-based fully distributed algorithm is proposed to address a minimal-time deadbeat consensus prediction problem for discrete-time high-order multi-agent systems (MASs). Therein, each agent can predict the consensus value with the minimum number of observable historical outputs of its own. Accordingly, compared to most e...

In this article, we propose a distributed guiding-vector-field (DGVF) algorithm for a team of robots to form a spontaneous-ordering platoon moving along a predefined desired path in the $n$ -dimensional Euclidean space. Particularly, by adding a path parameter as an additional virtual coordinate to each robot, the DGVF algorithm can eliminate t...

Residential energy consumption continues to climb steadily, requiring intelligent energy management strategies to reduce power system pressures and residential electricity bills. However, it is challenging to design such strategies due to the random nature of electricity pricing, appliance demand, and user behavior. This article presents a novel re...

Traditional machine learning relies on a centralized data pipeline for model training in various applications; however, data are inherently fragmented. Such a decentralized nature of databases presents the serious challenge for collaboration: sending all decentralized datasets to a central server raises serious privacy concerns. Although there has...

This paper addresses the dynamic target surrounding control problem for a class of heterogeneous multi-agent systems (MASs). To surround a motional target with a time-varying velocity, a distributed observer is established by employing perturbation system analysis, which can simultaneously retrieve both target state and dynamics. Then a distributed...

Residential load forecasting (RLF) is critical for power system operations. Different from traditional system-level load forecasting, studying RLF faces the challenges of high uncertainty. Besides, learning temporal dynamics within the residential load sequences is important. However, existing methods fail to effectively tackle the fore-mentioned c...

This article develops a closed-loop electrospinning process control system composed of a high-speed industrial camera, an interval type-2 (IT2) fuzzy logic controller (FLC) and a high-precision programmable micropump. A pure data-driven IT2 T-S fuzzy model with a micropump flow input and a fiber diameter output is established by a sparse Bayesian l...

Bootstrap aggregating (Bagging) and boosting are two popular ensemble learning approaches, which combine multiple base learners to generate a composite model for more accurate and more reliable performance. They have been widely used in biology, engineering, healthcare, etc. This paper proposes BoostForest, which is an ensemble learning approach us...

Sparse representation has been widely applied to image classification, where the key issue is to extract a suitable discriminative dictionary. To this end, we propose a joint dictionary and classifier learning algorithm based on a parameterized Bayesian model. Therein, the Gaussian priors of a dictionary endow it with the capability of discriminati...

A bstract Atrial Fibrillation (AF) is the most common cardiac rhythm disorder. It is associated with increased hospitalization, risk of heart failure, and risk of stroke. Once on AF, it can sometimes be difficult to revert to sinus rhythm (SR), potentially requiring pharmacological or electrical cardioversion. Earlier warning of an imminent switch...

A directed acyclic graph (DAG) is a common topology in biological, engineering, and social networks. A network topology is critical in determining a collective behavior of a network dynamic system. For example, the convergence rate of a consensus behavior in a multiagent system relies on the eigenvalues of the Laplacian associated with the network...

In this article, we investigate the event‐triggered robust output regulation problem for a class of nonlinear systems. Using the idea of time regularization, an event‐triggered mechanism with dwell time is proposed together with a model‐based control law, which avoids a practical convergence bound and excludes the Zeno behavior as well. The problem...

Collective decision making in a biological motion group requires fast and robust transmission of information. Typically, directional switching information propagation across the whole group obeys a linear dispersion law. However, conventional dynamic collective motion models, such as the Vicsek model and the Couzin model did not take into account u...

Distributed formation control has broad application prospects for unmanned swarm systems in both military and civil fields, such as cooperative convey protection, cooperative offshore patrolling and surrounding, cooperative ocean resource exploration, and so on. In this paper, a distributed escort formation control strategy with dynamic intermitten...

Drastic reduction in biodiversity has been a severe threat to ecosystems, which is exacerbated when losing few species leads to disastrous and even irreparable consequences. Therefore, revealing the mechanism underlying biodiversity loss is of uttermost importance. In this study, we show that abundant indirect interactions among mutualistic ecosyst...

This article proposes a distributed bearing-only controller for multiple unmanned surface vessels (USVs) to encircle and rotate evenly around a motional target with inter-USV topologies. The distributed control law consists of three terms, i.e., a bearing-only estimation term to approximate the target state, an upper-level surrounding term to fulfi...

Stochastic differential equations (SDEs) are mathematical models that are widely used to describe complex processes or phenomena perturbed by random noise from different sources. The identification of SDEs governing a system is often a challenge because of the inherent strong stochasticity of data and the complexity of the system’s dynamics. The pr...

Drastic reduction in biodiversity has been a severe threat to ecosystems, which is exacerbated when losing few species leads to disastrous and even irreparable consequences. Therefore, revealing the mechanism underlining biodiversity loss is of uttermost importance. In this study, we show that abundant indirect interactions among mutualistic ecosys...

In view of increasing concerns about climate change and global warming, various renewable energy sources are widely adopted in power systems to reduce greenhouse gas emissions. However, the widespread adoption of renewable energy sources exacerbates the problem of harmonics pollution. In order to improve power quality, it is urgent to develop a new...

This paper proposes a flexible formation tracking control protocol (FFTC) for multiple unmanned surface vessels (USVs) to pass through narrow water channels with unknown curvatures. An observer is developed to estimate the curvatures of channels. A flexible formation tracking control protocol is thereby designed to steer USV fleets to pass through...

This article proposes a distributed cooperative manipulation control scheme for multirobot systems to track reference trajectories with unknown payload dynamics, grasp positions, and external disturbances. An online learning module is established to estimate the payload dynamics. Then a wrench-synthetic trajectory tracking control protocol is there...

Surrounding formation control has potential applications in a wide range of fields such as cooperative escorting, hunting, patrolling, deployment, rescue, delivery and reconnaissance. In this paper, an event-triggered control algorithm is developed to tackle the multiple dynamic targets surrounding formation control problem. Essentially, the propos...

Coronavirus disease 2019 (COVID-19) has become a worldwide pandemic. Hospitalized patients of COVID-19 suffer from a high mortality rate, motivating the development of convenient and practical methods that allow clinicians to promptly identify high-risk patients. Here, we have developed a risk score using clinical data from 1479 inpatients admitted...

Steering jam is a common fault of autonomous surface vessels (ASVs) frequently encountered in practical operations. In such a scenario, the allowable ASV moving direction is confined to a narrow zone, which inevitably induces technical challenges for harbor-returning operations of ASVs. As a remedy, we propose a moving-direction fault-tolerant cont...

Complex systems consist of various interconnected components, and they normally display peculiar behaviors. Since individual components interact with each other, the causality is quite complicated. Therefore, it is crucial to reveal the underlying principle of collective behaviors. As one of key research fields, multi-agent systems have attracted s...

In this chapter, we consider workload partition problems in order to dynamically sweep an uncertain region by multiple mobile agents. A distributed algorithm for mobile agents is designed to yield equal workload in each subregion by partitioning the entire region in real time. Due to the uncertainty in the region, the agents do not have the global...

This chapter discusses decentralized sweep coverage of a given region with parametric uncertainties by multiple agents. With parametric uncertainty in the environment, we present an adaptive sweep coverage algorithm to guarantee the region coverage by simultaneously sweeping the region and partitioning the workload. The adaptive technique with pers...

This chapter addresses a sweep coverage problem of multi-agent systems with general network topologies. To deal with environmental uncertainties, we present discrete-time sweep coverage algorithms to guarantee the complete coverage of the given region by sweeping in parallel with workload partition. Moreover, the error between actual coverage time...

In this chapter, we present a simple yet effective routing strategy inspired by coverage control, which delays the onset of congestion on traffic networks by introducing a control parameter. The routing algorithm allows a trade-off between the congestion level and the distance to the destination. Numerical verification of the coverage control strat...

This chapter proposes a coverage-based formulation for the interception problem against supersonic fight vehicles with multiple decoys. A cooperative guidance algorithm is designed to deploy a team of interceptors for maximizing the interception probability. In addition, an optimal control approach is developed to drive the interceptors for arrivin...

This chapter addresses the sweep coverage problem of MAS in the uncertain environment. A novel formulation of distributed sweep coverage is proposed for multiple agents to cooperatively complete the workload in the coverage region. To save the sweep time, each agent takes part in partitioning the whole region using its partition bar while sweeping...

This chapter summarizes main results on cooperative coverage control of MAS by reviewing theoretical formulation of multi-agent coverage control and its practical applications and then discusses possible research directions in the future, which include wide-area cooperative coverage control via UAV-Satellite coordination, coverage control design fo...

This chapter addresses the coverage problem of multiple mobile agents in the uncertain environment. A new formulation is proposed for monitoring random events (e.g., forest fire, geohazard, avalanche) in the coverage region, the random events can be described by a probability density function. Meanwhile, a distributed control method is developed fo...

This chapter proposes a novel sweep coverage formulation for a multi-agent system to cover a region with uncertain workload density, and it provides a decentralized coverage algorithm based on the formulation. To achieve the coverage, the concerned region is divided into a finite number of stripes, and the algorithm incorporates two operations on s...

Cooperative sweep coverage of multiagent systems (MASs) has found broad applications in various fields. This article proposes a scheme to address the sweep coverage problem of MASs within uncertain environments. In the proposed formulation, the coverage region is divided into multiple stripes, of which each has the workload completed by MASs in seq...

This paper proposes a distributed energy-based landing allocation method of multiple unmanned aerial vehicles (UAVs) on multiple unmanned surface vessels (USVs). First, an optimization function is established, which consists of the limited energy battery, the flight distance and the flight speed. Then, a distributed landing allocation scheme is des...

The mechanisms inducing unpredictably directional switches in collective and moving biological entities are largely unclear. Deeply understanding such mechanisms is beneficial to delicate design of biologically-inspired devices with particular functions. Here, articulating a framework that integrates data-driven, analytical, and numerical methods,...

The fluctuations in electricity prices and intermittency of renewable energy systems necessitate the adoption of online energy management schemes in industrial microgrids. However, it is challenging to design effective and optimal online rolling horizon energy management strategies that can deliver assured optimality, subject to the uncertainties o...

A large part of biological collective behaviors involves motional formation patterns like migration, vortex, aggregation, etc., in three-dimensional space, but the phase transition principles among these patterns still remain a dilemma. In this letter, by tweaking the vision range of the particles in a minimal collective motion model, phase transit...