# Jie Huang's research while affiliated with The University of Hong Kong and other places

## Publications (320)

Chapter
This chapter studies the leader-following consensus problem of multiple rigid-body systemsRigid-body system. The attitude parametrization, kinematics, and dynamics of a rigid-body system are first given in Sect. 6.1. Then, in Sect. 6.2, we treat three cases of the standard attitude control problem for a single rigid-body system. Section 6.3 studies...
Preprint
Recently, an asymptotic convergence result on the distributed state estimation problem for linear systems over jointly connected switching networks was given. This paper further presents an exponential convergence result on the distributed state estimation problem for linear systems over jointly connected switching networks. In comparison with the...
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Article
In this article, we study the leader-following attitude consensus and disturbance rejection problem of multiple uncertain rigid spacecraft systems over jointly connected switching networks. In contrast with the previous work, which can only handle disturbances in the form of step functions and trigonometric functions via the internal model approach...
Article
A standard assumption on the existence of the distributed observer or adaptive distributed observer for a linear leader system over jointly connected switching networks is that none of the eigenvalues of the system matrix of the leader system have positive real parts. In this paper, after establishing a stability result for a class of linear period...
Article
This paper investigates the semi-global robust output regulation problem for a class of uncertain nonlinear systems via a sampled-data output feedback control law. What makes the results interesting is that the nonlinearities of the proposed system do not have to satisfy linear growth condition and the uncertain parameters of our system are allowed...
Article
In this article, we study the leader‐following formation control problem for a group of rigid body systems whose followers' motions are described by dual quaternion equations. A few features are as follows. First, we introduce an exosystem to generate the leader's trajectory as well as the formation configuration, which can produce a large class of...
Article
While the estimation problem of the unknown frequencies for a continuous-time multi-tone sinusoidal signal was thoroughly solved in the early 2000s, the discrete-time version of this problem was studied only recently via a nonlinear control approach. In this paper, we present a simpler approach to the estimation problem of the unknown frequencies f...
Article
In this article, we study the cooperative output regulation problem for heterogeneous linear multi‐agent systems by the distributed sampled‐data control approach. We consider two cases. The first case is that the state of the leader system is constant. For this case, we show that the cooperative output regulation problem is solvable exactly by a di...
Article
The existing results on the leader-following consensus problem for linear continuous-time multi-agent systems over jointly connected switching digraphs rely on the assumption that the system matrices do not have eigenvalues with positive real parts. In this paper, to remove this assumption, we first establish a stability result for a class of linea...
Article
In this article, we study the leader-following practical attitude consensus problem of a group of multiple uncertain rigid spacecraft systems over jointly connected networks by a distributed event-triggered control law. We first establish a lemma that allows the problem to be converted to a distributed practical stabilization problem of a well-defi...
Article
In this paper, we study the leader-following consensus problem for multiple Euler-Lagrange (EL) systems with natural damping over static and connected communication networks by a distributed position feedback control law. By combining the adaptive distributed observer for a leader system and the dynamic compensator technique for dealing with a sing...
Article
The existing results on the adaptive distributed observer for an uncertain leader system are restricted to connected static networks. In this article, we extend the existing results to acyclic every‐time connected switching networks. As an application of the adaptive distributed observer, we solve the leader‐following attitude consensus problem of...
Article
The adaptive distributed observer approach has been an effective tool for synthesizing a distributed control law for solving various control problems of leader–follower multiagent systems. However, the existing adaptive distributed observer needs to make use of the full state of the leader system. This assumption not only precludes many practical a...
Preprint
The adaptive distributed observer approach has been an effective tool for synthesizing a distributed control law for solving various control problems of leader-follower multiagent systems. However, the existing adaptive distributed observer needs to make use of the full state of the leader system. This assumption not only precludes many practical a...
Article
In this paper, we study the robust output regulation of linear systems by an event-triggered output feedback control law. We first summarize the solvability of the linear robust output regulation problem by the internal model design. Then we implement this continuous-time control law by an event-triggered output feedback control law together with a...
Preprint
In this article, we update the reference [14] in two aspects. First, we note that in order for the control law (12) in [14] to be equivalent to the control law (3) in [14], we need to assume that the samplings for all subsystems must be synchronous, i.e., we need to assume that $T_{i}=T$ for all $i=1,\cdots,N$. Second, we extend our results from pe...
Article
In this paper, we study the robust bipartite output regulation problem for a class of linear uncertain multi-agent systems, which aims at the design of a distributed control law for linear uncertain multi-agent systems subject to a signed digraph such that the closed-loop system is internally stable and the norm of the output of every follower subs...
Article
In this paper, we first establish an exponential stability result for a class of linear switched systems and then apply this result to show the existence of the distributed observer for a discrete-time leader system over jointly connected switching networks. A special case of this result leads to the solution of a leader-following consensus problem...
Article
The existing results on the leader-following consensus problem for linear discrete-time multi-agent systems over jointly connected switching digraphs only apply to systems without exponentially unstable modes. In this note, we will remove this restriction by employing a more general class of distributed control laws which includes a set of weight c...
Article
Recently, an adaptive distributed observer for a class of uncertain leader systems was established over undirected connected graphs. In this paper, we further study the same problem over directed connected graphs. It is shown that, if the graph is acyclic, then an adaptive distributed observer exists in the sense that it can not only estimate the l...
Article
In this paper, we investigate the leader-following bipartite consensus problem of multiple uncertain Euler-Lagrange (EL) systems over signed switching networks. We first extend the distributed observer for a linear leader system over signed communication networks from the static case to the jointly connected switching case. Based on such a distribu...
Article
In this article, we consider the event‐triggered cascade high‐gain observer (ETCHGO) for a class of nonlinear systems. By cascading lower dimensional observers, we design a cascade high‐gain observer together with a Zeno‐free event‐triggered mechanism to estimate the state of the plant. We show that the ETCHGO has the same steady‐state performance...
Article
In this paper, we study the leader-following formation tracking problem for multiple quadrotor helicopters over static and connected communication networks via the distributed observer approach. With the virtual leader system being modeled by a linear exosystem, we develop a distributed control law that can accomplish the formation tracking for a l...
Article
In this paper, we study the output regulation problem for linear systems by the aperiodic sampled-data control approach. Suppose the problem is solvable by a continuous-time static state feedback control law and a continuous-time dynamic output feedback control law. Then, we first show that, if the exogenous signal is constant, then the output regu...
Article
In this paper, we consider the sampled-data leader-following consensus problem for a class of general linear multi-agent systems. A distributed asynchronous sampled-data state feedback control law is proposed. We show by Lyapunov analysis that the problem can be solved by the proposed control law as long as the sampling periods of all agents are sm...
Article
In this paper, we study the cooperative robust output regulation problem for a class of nonlinear multi-agent systems subject to a nonlinear leader system. We first establish a result on the existence of a distributed observer for a class of nonlinear leader systems. Then, we convert the cooperative robust output regulation problem into a robust st...
Article
In this paper, the leader‐following consensus with disturbance rejection problem of uncertain Euler‐Lagrange systems is studied by the adaptive distributed observer approach. We first present a key lemma that guarantees the existence of an exponentially convergent adaptive distributed observer for linear leader systems without exponential growing m...
Preprint
Full-text available
In this paper, we study the leader-following consensus problem of multiple Euler-Lagrange systems subject to an uncertain leader system. We first establish an adaptive distributed observer for a neutrally stable linear leader system whose system matrix is not known exactly. Under standard assumptions, this adaptive distributed observer can estimate...
Article
In this paper, we further consider the leader-following attitude consensus problem of multiple rigid body systems subject to jointly connected switching networks by a distributed attitude feedback control law. Since the network is switching, the closed-loop system is discontinuous. We overcome this difficulty by a generalized Barbalat's lemma. More...
Article
The leader-following consensus problem of a group of uncertain multiple rigid body systems subject to static networks has been solved by a distributed adaptive control law utilizing the distributed observer for the leader system. In this paper, we extend this result to jointly connected switching networks. This extension needs to overcome the disco...
Article
The cooperative global robust output regulation problem for multi-agent systems is a generalization of the leader-following consensus problem. The problem has been studied for various multi-agent systems over connected static networks and for some special classes of nonlinear multi-agent systems over jointly connected switching networks. In this pa...
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The leader-following consensus problem for a class of multiple robot manipulators subject to a static and connected network has been studied recently by a distributed position feedback control law. In this paper, we will further study the same problem under a switching network satisfying the jointly connected condition. Since the switching network...
Chapter
Recently, an adaptive distributed observer for a class of uncertain leader systems was established over undirected connected graphs. In this paper, we further study the same problem over directed connected graphs. It is shown that, if the graph is acyclic, then an adaptive distributed observer exists in the sense that it can not only estimate the l...
Article
In this paper, we study the cooperative output regulation problem of linear heterogeneous multi-agent systems subject to an uncertain leader system. A key component of our control law is the adaptive distributed observer for an uncertain leader system proposed recently by ourselves. We first show that this adaptive distributed observer is capable o...
Article
This technical communique studies the robust output regulation problem of uncertain discrete-time linear systems by quantized output feedback control. We show that, under the same assumptions as those that guarantee the solvability of the robust output regulation problem by a dynamic output feedback control law, our problem is also solvable by a dy...
Article
In this paper, we first extend an existing stability result for a class of linear switched systems. This extended result will relax the existence conditions of the output-based distributed observer for a leader system subject to jointly connected switching communication networks in the literature. As an application of this output-based distributed...
Preprint
In this paper, we first establish an exponential stability result for a class of linear switched systems and then apply this result to show the existence of the distributed observer for a discrete-time leader system over jointly connected switching networks. A special case of this result leads to the solution of a leader-following consensus problem...
Article
In this paper, we study the leader-following consensus problem of multiple Euler-Lagrange EL systems subject to an uncertain leader system. We first establish an adaptive distributed observer for a neutrally stable linear leader system whose system matrix is not known exactly. Under standard assumptions, this adaptive distributed observer can estim...
Article
In this paper, we further study the leader-following consensus problem for a class of linear discrete-time multi-agent systems subject to jointly connected switching digraphs. We first establish a stability result for a class of linear switched systems under a more relaxed assumption than those in the literature. Then, we apply this stability resul...
Article
This paper proposes a novel Krasovskii–LaSalle theorem for discrete-time switched linear time-invariant systems. The result is utilized to guarantee exponential convergence of both leaderless and leader-following consensus of discrete-time multi-agent systems under jointly connected switching network topology. Different from the continuous-time mul...
Article
The leader-following consensus problem for linear discrete-time multi-agent systems has been studied in the literature using $H_{\infty}$ Riccati inequality design and $H_{2}$ Riccati equation design methods, respectively. These two methods lead to a solvability condition in terms of an inequality which relies on a scaling gain and a fixed weight...
Article
In this paper, we study the asymptotic output tracking problem for a class of minimum phase uncertain linear discrete-time multi-agent systems over jointly connected digraphs. As the systems contain arbitrarily large uncertain parameters, the robust feedback control technique does not work. We develop a distributed adaptive control law composed of...
Article
In this note, we first present a systematic framework for designing a distributed control law for solving a cooperative control problem of nonlinear multi-agent systems with a nonlinear leader system. The distributed control law is composed of a purely decentralized control law and a distributed observer for the leader system based on the certainty...
Article
The leader-following attitude consensus problem of multiple rigid body systems has been studied by the distributed observer approach. The key assumption in the existing results is that the communication network among the rigid body systems is static and connected. Nevertheless, this assumption is undesirable since, typically, the communication netw...
Article
An adaptive distributed observer was recently proposed to solve the cooperative output regulation problem for discrete-time linear multi-agent systems. The validity of this approach relies on the assumptions that all the eigenvalues of the leader's system matrix are inside or on the unit circle and the solution to the regulator equations is unique....
Article
The consensus problem for multiple Euler-Lagrange systems has been extensively studied under various assumptions on the connectivity of the communication graph. In practice, it is desirable to enable the control law the capability of maintaining the connectivity of the communication graph, thus achieving consensus without assuming the connectivity...
Article
In this paper, we study the cooperative global robust practical output regulation problem for a class of second-order uncertain nonlinear multiagent systems via a distributed event-triggered state feedback control strategy. Compared with the existing work, one of the main challenges is that we need to design two distributed internal models to learn...
Article
In this paper, we study the event-triggered global robust practical output regulation problem for a class of nonlinear systems in output feedback form with any relative degree. Our approach consists of the following three steps. First, we design an internal model and an observer to form the so-called extended augmented system. Second, we convert th...
Article
The cooperative robust output regulation problem for a class of second-order nonlinear multi-agent systems with an exactly known exosystem has been studied recently. This paper further studies the same problem for the same class of systems subject to an uncertain exosystem. We first show that the problem can be converted into the adaptive stabiliza...
Article
In this paper, we study the cooperative robust output regulation problem for linear uncertain multiagent systems with both communication delay and input delay by the distributed internal model approach. The problem includes the leader-following consensus problem of linear multiagent systems with time delay as a special case. We first generalize the...
Article
In this paper, we first propose a self-tuning distributed observer for a multi-agent system, which is capable of providing the estimation of the leader’s signal to various followers without assuming all the followers know the system matrix of the leader. We then further develop a novel adaptive distributed control law to solve the cooperative outpu...
Article
In this paper, we study the leader-following rendezvous and flocking problems for a class of second-order nonlinear multiagent systems, which contain both external disturbances and plant uncertainties. What differs our problems from the conventional leader-following consensus problem is that we need to preserve the connectivity of the communication...
Article
In this paper, we consider the event-triggered cooperative robust practical output regulation problem for a class of linear minimum-phase multi-agent systems. We first convert our problem into the cooperative robust practical stabilization problem of a well defined augmented system based on the distributed internal model approach. Then, we design a...
Article
The cooperative output regulation problem for singular multi-agent systems subject to static networks was studied recently under the assumption that each follower system satisfies the standard assumption. In this paper, we further study the same problem for singular multi-agent systems subject to jointly connected switching networks. First, by intr...
Article
This paper studies the cooperative output regulation problem for a class of nonlinear multi-agent systems with unknown control directions subject to jointly connected switching networks. Our approach integrates three techniques, namely, the distributed internal model, the Nussbaum gain technique, and the adaptive distributed observer. An adaptive d...
Article
This paper studies the event-triggered cooperative global robust output regulation problem for a class of nonlinear multi-agent systems via a distributed internal model design. We show that our problem can be solved practically in the sense that the ultimate bound of the tracking error can be made arbitrarily small by adjusting a design parameter i...
Article
In this paper, we study the event-triggered global robust output regulation problem for a class of nonlinear systems in output feedback form with unity relative degree. We first convert the problem into the event-triggered global robust stabilization problem of a well defined augmented system by the internal model approach. Then, we solve the stabi...
Article
The leader-following attitude consensus problem of multiple rigid body systems has been studied by the distributed observer approach. The distributed observer is able to estimate the reference signals generated by a target system under the assumption that each rigid body system knows the two system matrices of the target system. In this paper, we p...
Article
In this paper, we study the cooperative global robust output regulation problem for nonlinear multi-agent systems in output feedback form with any relative degree subject to directed switching networks. Through the augmentation with a distributed internal model and a distributed observer of the given system, we first convert the original problem in...
Article
This note studies the global robust output regulation problem for a class of nonlinear systems by an output-based event-triggered control law. First, we convert the problem into the event-triggered global robust stabilization problem of a well defined augmented system based on the internal model approach. Then, we design an output-based event-trigg...
Article
This paper presents a discrete-time recurrent neural network approach to solving systems of linear equations with two features. First, the system of linear equations may not have a unique solution. Second, the system matrix is not known precisely, but a sequence of matrices that converges to the unknown system matrix exponentially is known. The pro...
Article
The leader-following consensus problem for multiple Euler–Lagrange systems has been extensively studied for various scenarios. Under the assumption that the communication graph is jointly connected, one of our recent papers gave the solution for the case where the leader system can generate a combination of arbitrary step signal, arbitrary ramp sig...
Article
In this paper, we study the cooperative robust output regulation problem for discrete-time linear multi-agent systems with both communication and input delays by distributed internal model approach. We first introduce the distributed internal model for discrete-time multi-agent systems with both communication and input delays. Then, we define so-ca...
Article
The cover image, by Jie Huang and He Cai, is based on the Research Article Leader-following attitude consensus of multiple uncertain spacecraft systems subject to external disturbance, 10.1002/rnc.3595.
Article
In this paper, we consider the robust practical output regulation problem for a class of SISO uncertain linear minimum-phase systems subject to external disturbances by an output-based event-triggered control law, where the reference inputs and the external disturbances are both generated by a so-called exosystem with known dynamics. Our approach c...
Article
Recently, the robust output regulation problem for continuous-time linear systems with both input and communication time-delays was studied. This paper will further present the results on the robust output regulation problem for discrete-time linear systems with input and communication delays. The motivation of this paper comes from two aspects. Fi...
Article
In this paper, we study the cooperative output regulation problem for discrete-time linear time-delay multi-agent systems subject to jointly connected switching networks. Our distributed control law is composed of a purely decentralized control law and a distributed switched observer. In contrast to the same problem with static networks, the closed...
Article
The cooperative output regulation problem of linear multi-agent systems using distributed observer approach has been solved under the assumption that each follower knows the system matrix of the leader system. To remove this assumption, in this paper, a distributed control scheme utilizing the adaptive distributed observer has been proposed, which...
Article
This paper studies the cooperative global robust output regulation problem for a class of heterogeneous second-order nonlinear uncertain multiagent systems with jointly connected switching networks. The main contributions consist of the following three aspects. First, we generalize the result of the adaptive distributed observer from undirected joi...
Article
The distributed observer approach has been an effective way to synthesise a distributed control law for a multi-agent system. However, this approach assumes that all the followers know the system matrix of the leader system, and this assumption may not be desirable in some applications. In this note, we will further introduce an adaptive distribute...
Article
This paper studies the leader-following consensus problem for a class of second-order nonlinear multi-agent systems subject to linearly parameterized uncertainty and disturbance. The problem is solved by integrating the adaptive control technique and the adaptive distributed observer method. The design procedure is illustrated by an example with a...
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This paper studies the leader-following rendezvous with connectivity preservation problem for multiple double-integrator systems subject to external disturbances via a self-tuning adaptive distributed observer approach. This approach offers two advantages over the existing approach. First, it removes the existing assumption that all the followers k...
Article
The attitude consensus problem of multiple rigid spacecraft systems is one of the key issues in spacecraft formation flying and has been extensively studied. In this paper, we further consider the leader-following attitude consensus problem of multiple rigid uncertain spacecraft systems subject to a class of multi-tone sinusoidal disturbances with...
Article
In this paper, we study the leader-following attitude consensus problem for multiple rigid body systems by a distributed unit quaternion-based attitude feedback control law. The control law is based on the certainty equivalence principle and contains a distributed observer for estimating the state of the leader and an auxiliary system compensating...
Article
In this paper, we study the cooperative output regulation problem for linear time-delay multi-agent systems subject to jointly connected switching network. We first establish two lemmas that lay the foundation for solving the problem and then present the solution to the problem by both the dynamic state feedback control law and the dynamic measurem...
Article
In this paper, we consider the cooperative robust output regulation problem for a class of heterogeneous linear uncertain minimum-phase multi-agent systems by an output-based event-triggered distributed control law. First, we convert the cooperative robust output regulation into the cooperative robust stabilization problem of a well defined augment...
Article
The leader-following consensus problem for multiple Euler-Lagrange systems was studied recently by the adaptive distributed observer approach under the assumptions that the leader system is neurally stable and the communication network is jointly connected and undirected. In this paper, we will study the same problem without assuming that the leade...

## Citations

... A continuous finite-time control strategy was designed with these two observers and a power integrator technique. Wang and Huang [83] focused on the leader-follower attitude consensus of multiple spacecraft subject to disturbances under jointly connected switching graphs. They integrated the adaptive distributed observer technique and adaptive learning control technique to design a controller that could handle bounded disturbances and the case under jointly connected switching graphs. ...
... where R ∈ R 3×3 , Ω ∈ R 3 , x ∈ R 3 , v ∈ R 3 , w ∈ R 2 , and y ∈ R 3 . The dynamics (52)-(57) is in standard form and therefore, a feedback control law (12) up to degree r is given bȳ ...
... In [17], a state-dependent Riccati equation filter is proposed for a single-frequency unbiased sinusoidal signal without any convergence analysis. Linear filters with linear adaptation law are proposed in [18]. However, the estimator order is higher than the number of parameters. ...
... Euler-Lagrange (EL) dynamics can be used to describe many real-world systems such as aircrafts [1], manipulators [2], mobile robots [3], multi-agent networks [4] and many more [5], [6]. In these and other applications, the dynamics of the system may be not known exactly, e.g. ...
... Focusing on uncertain linear systems, the work [12] considers norm-bounded uncertainties with continuous measurements, while [19], [20] develop mechanism under the assumption that the system is minimum-phase. Most recently, the work [21] studies the problem of output regulation together along with an event-triggering mechanism in which the robustness is guaranteed for an unstructured open uncertainty set. Concerning nonlinear systems, the recent work [22] proposes an event-triggered mechanism under the assumption that the system is input-to-state stable. ...
... As interactions among agents include competitive and cooperative links, constructing an effective control protocol to realize bipartite consensus under switching topologies is in great demand and challenging. In [23], based on a distributed observer and the certainty equivalence principle, the leaderfollowing bipartite consensus problem of multiple uncertain Euler-Lagrange systems over signed switching networks was solved. Later, the signed consensus for MASs over fixed and switching topologies was concerned in [24]. ...
... However, convergence of the estimated unknown leader's dynamic matrix to the actual value of the leader's dynamic matrix is not considered in Reference 22. Asymptotic convergence of the leader's dynamics is guaranteed in References 23,24 using an adaptive distributed observer. The authors in References 22,24 only use the relative output information to estimate the unknown leader's dynamic and guarantee the asymptotic convergence. The aforementioned work only guarantees asymptotic convergence. ...
... As a pioneering work on consensus control, Olfati et al. [25] studied the consensus of dynamic agents with fixed and switching topologies. Then, more and more attention has been paid to the situation of switching topologies, such as jointly connected switching digraphs [26,27], Markov switching topologies [28,29] and so on. Here, we should point out that nearly all of the work mentioned above [25][26][27][28][29] need to design specific distributed protocols to achieve the consensus of MASs, and control cost is ignored, which cannot meet the growing desires of engineering. ...
... For instance, in Reference 11, the author proposed an event-triggered scheduler based on a state feedback controller in order to solve stabilization problem on embedded processors while event-triggered adaptive control technique was investigated in References 12 and 13 and event-triggered output regulation problem was solved in Reference 14. The event-triggered state estimation problem has also attracted significant research attention (see, e.g., References 10,[15][16][17][18][19][20][21][22][23]. In particular, for stochastic dynamical systems, in Reference 15, an event-triggered particle filter was proposed for smart grids with limited communication bandwidth infrastructure, while an event-triggered cubature Kalman filter was designed in Reference 17 for estimating the set vectors of power systems. ...
... In fact, only recently, the PET/sampled data output regulation problem has been solved for linear systems [23], [24]. The nonlinear dynamics of the considered systems will cause many difficulties to the PET output regulation problem. ...