In this paper,the leader-follower consensus problem for a multiple flexible manipulator network with actuator failures,parameter uncertainties,and unknown time-varying boundary disturbances is addressed.The purpose of...In this paper,the leader-follower consensus problem for a multiple flexible manipulator network with actuator failures,parameter uncertainties,and unknown time-varying boundary disturbances is addressed.The purpose of this study is to develop distributed controllers utilizing local interactive protocols that not only suppress the vibration of each flexible manipulator but also achieve consensus on joint angle position between actual followers and the virtual leader.Following the accomplishment of the reconstruction of the fault terms and parameter uncertainties,the adaptive neural network method and parameter estimation technique are employed to compensate for unknown items and bounded disturbances.Furthermore,the Lyapunov stability theory is used to demonstrate that followers’angle consensus errors and vibration deflections in closed-loop systems are uniformly ultimately bounded.Finally,the numerical simulation results confirm the efficacy of the proposed controllers.展开更多
This paper studies the dynamic event-triggered leader-follower consensus of nonlinear multi-agent systems(MASs)under directed weighted graph containing a directed spanning tree,and also considers the effects of distur...This paper studies the dynamic event-triggered leader-follower consensus of nonlinear multi-agent systems(MASs)under directed weighted graph containing a directed spanning tree,and also considers the effects of disturbances and leader of non-zero control inputs in the system.Firstly,a novel distributed control protocol is designed for uncertain disturbances and leader of non-zero control inputs in MASs.Secondly,a novel dynamic event-triggered control(DETC)strategy is proposed,which eliminates the need for continuous communication between agents and reduces communication resources between agents.By introducing dynamic thresholds,the complexity of excluding Zeno behavior within the system is reduced.Finally,the effectiveness of the proposed theory is validated through numerical simulation.展开更多
In this study,we solve the finite-time leader-follower consensus problem of discrete-time second-order multi-agent systems(MASs)under the constraints of external disturbances.First,a novel consensus scheme is designed...In this study,we solve the finite-time leader-follower consensus problem of discrete-time second-order multi-agent systems(MASs)under the constraints of external disturbances.First,a novel consensus scheme is designed using a novel adaptive sliding mode control theory.Our adaptive controller is designed using the traditional sliding mode reaching law,and its advantages are chatter reduction and invariance to disturbances.In addition,the finite-time stability is demonstrated by presenting a discrete Lyapunov function.Finally,simulation results are presented to prove the validity of our theoretical results.展开更多
In this paper,robustness properties of the leader-follower consensus are considered.Forsimplicity of presentation,the attention is focused on a group of continuous-time first-order dynamicagents with a time-invariant ...In this paper,robustness properties of the leader-follower consensus are considered.Forsimplicity of presentation,the attention is focused on a group of continuous-time first-order dynamicagents with a time-invariant communication topology in the presence of communication errors.In orderto evaluate the robustness of leader-follower consensus,two robustness measures are proposed:the L_2gain of the error vector to the state of the network and the worst case L_2 gain at a node.Althoughthe L_2 gain of the error vector to the state of the network is widely used in robust control design andanalysis,the worst case L_2 gain at a node is less conservative with respect to the number of nodes inthe network.It is thus suggested that the worst case L_2 gain at a node is used when the robustnessof consensus is considered.Theoretical analysis and simulation results show that these two measuresare sensitive to the communication topology.In general,the 'optimal' communication topology thatcan achieve most robust performance with respect to either of the proposed robustness measures isdifficult to characterize and/or obtain.When the in-degree of each follower is one,it is shown thatboth measures reach a minimum when the leader can communicate to each node in the network.展开更多
This paper is concerned with the cooperative target pursuit problem by multiple agents based on directed acyclic graph. The target appears at a random location and moves only when sensed by the agents, and agents will...This paper is concerned with the cooperative target pursuit problem by multiple agents based on directed acyclic graph. The target appears at a random location and moves only when sensed by the agents, and agents will pursue the target once they detect its existence. Since the ability of each agent may be different, we consider the heterogeneous multi-agent systems. According to the topology of the multi-agent systems, a novel consensus-based control law is proposed, where the target and agents are modeled as a leader and followers, respectively. Based on Mason＇s rule and signal flow graph analysis, the convergence conditions are provided to show that the agents can catch the target in a finite time. Finally, simulation studies are provided to verify the effectiveness of the proposed approach.展开更多
This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communica...This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communication topology. Based on the relative states of the neighbor agents and a subset of absolute states of the agents, distributed static H∞controllers are proposed. The concept of an H∞performance region is extended to the directed graph situation. Then the results are used to solve the leader–follower H∞consensus problem. Sufficient conditions are proposed based on bounded real lemma and algebraic graph theory. The effectiveness of the theoretical results is illustrated via numerical simulations.展开更多
This paper is concerned with the stochastic bounded consensus tracking problems of leader-follower multi-agent systems, where the control input of an agent can only use the information measured at the sampling instant...This paper is concerned with the stochastic bounded consensus tracking problems of leader-follower multi-agent systems, where the control input of an agent can only use the information measured at the sampling instants from its neighbours or the virtual leader with a time-varying reference state, and the measurements are corrupted by random noises. The probability limit theory and the algebra graph theory are employed to derive the necessary and sufficient conditions guaranteeing the mean square bounded consensus tracking. It is shown that the maximum allowable upper boundary of the sampling period simultaneously depends on the constant feedback gains and the network topology. Furthermore, the effects of the sampling period on the tracking performance are analysed. It turns out that from the view point of the sampling period, there is a trade-off between the tracking speed and the static tracking error. Simulations are provided to demonstrate the effectiveness of the theoretical results.展开更多
基金This work was supported in part by the National Key Research and Development Program of China(2021YFB3202200)Guangdong Basic and Applied Basic Research Foundation(2020B1515120071,2021B1515120017).
文摘In this paper,the leader-follower consensus problem for a multiple flexible manipulator network with actuator failures,parameter uncertainties,and unknown time-varying boundary disturbances is addressed.The purpose of this study is to develop distributed controllers utilizing local interactive protocols that not only suppress the vibration of each flexible manipulator but also achieve consensus on joint angle position between actual followers and the virtual leader.Following the accomplishment of the reconstruction of the fault terms and parameter uncertainties,the adaptive neural network method and parameter estimation technique are employed to compensate for unknown items and bounded disturbances.Furthermore,the Lyapunov stability theory is used to demonstrate that followers’angle consensus errors and vibration deflections in closed-loop systems are uniformly ultimately bounded.Finally,the numerical simulation results confirm the efficacy of the proposed controllers.
基金supported by the National Natural Science Foundation of China(62173175)。
文摘This paper studies the dynamic event-triggered leader-follower consensus of nonlinear multi-agent systems(MASs)under directed weighted graph containing a directed spanning tree,and also considers the effects of disturbances and leader of non-zero control inputs in the system.Firstly,a novel distributed control protocol is designed for uncertain disturbances and leader of non-zero control inputs in MASs.Secondly,a novel dynamic event-triggered control(DETC)strategy is proposed,which eliminates the need for continuous communication between agents and reduces communication resources between agents.By introducing dynamic thresholds,the complexity of excluding Zeno behavior within the system is reduced.Finally,the effectiveness of the proposed theory is validated through numerical simulation.
基金supported by the National Natural Science Foundation of the People’s Republic of China“Fixed-time consensus of multi-agent systems with objective optimization”(62003289)“Finite/fixed and prescribed-time distributed optimization consensus of multi-agent systems”(62163035).
基金Project supported by the National Natural Science Foundation of China(Nos.61873300 and 61722312)the Fundamental Research Funds for the Central Universities,China(Nos.FRFMP-20-11 and FRF-IDRY-20-030)。
文摘In this study,we solve the finite-time leader-follower consensus problem of discrete-time second-order multi-agent systems(MASs)under the constraints of external disturbances.First,a novel consensus scheme is designed using a novel adaptive sliding mode control theory.Our adaptive controller is designed using the traditional sliding mode reaching law,and its advantages are chatter reduction and invariance to disturbances.In addition,the finite-time stability is demonstrated by presenting a discrete Lyapunov function.Finally,simulation results are presented to prove the validity of our theoretical results.
基金supported by the National Natural Science Foundation of China under Grant No. 60774005
文摘In this paper,robustness properties of the leader-follower consensus are considered.Forsimplicity of presentation,the attention is focused on a group of continuous-time first-order dynamicagents with a time-invariant communication topology in the presence of communication errors.In orderto evaluate the robustness of leader-follower consensus,two robustness measures are proposed:the L_2gain of the error vector to the state of the network and the worst case L_2 gain at a node.Althoughthe L_2 gain of the error vector to the state of the network is widely used in robust control design andanalysis,the worst case L_2 gain at a node is less conservative with respect to the number of nodes inthe network.It is thus suggested that the worst case L_2 gain at a node is used when the robustnessof consensus is considered.Theoretical analysis and simulation results show that these two measuresare sensitive to the communication topology.In general,the 'optimal' communication topology thatcan achieve most robust performance with respect to either of the proposed robustness measures isdifficult to characterize and/or obtain.When the in-degree of each follower is one,it is shown thatboth measures reach a minimum when the leader can communicate to each node in the network.
基金supported by the National Basic Research Program of China (Grant No. 2010CB731800)the Key Project of the National Natural Science Foundation of China (Grant No. 60934003)+2 种基金the National Natural Science Foundation of China (Grant No. 61074065)the Key Project for the Natural Science Research of Hebei Education Department,China (Grant No. ZD200908)the Key Project for the Shanghai Committee of Science and Technology (Grant No. 08511501600)
文摘This paper is concerned with the cooperative target pursuit problem by multiple agents based on directed acyclic graph. The target appears at a random location and moves only when sensed by the agents, and agents will pursue the target once they detect its existence. Since the ability of each agent may be different, we consider the heterogeneous multi-agent systems. According to the topology of the multi-agent systems, a novel consensus-based control law is proposed, where the target and agents are modeled as a leader and followers, respectively. Based on Mason＇s rule and signal flow graph analysis, the convergence conditions are provided to show that the agents can catch the target in a finite time. Finally, simulation studies are provided to verify the effectiveness of the proposed approach.
文摘This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communication topology. Based on the relative states of the neighbor agents and a subset of absolute states of the agents, distributed static H∞controllers are proposed. The concept of an H∞performance region is extended to the directed graph situation. Then the results are used to solve the leader–follower H∞consensus problem. Sufficient conditions are proposed based on bounded real lemma and algebraic graph theory. The effectiveness of the theoretical results is illustrated via numerical simulations.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61203147,60973095,60804013,and 61104092)the Fundamental Research Funds for the Central Universities,China(Grant Nos.JUSRP111A44,JUSRP21011, and JUSRP11233)+1 种基金the Foundation of State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology(HUST),China(Grant No.DMETKF2010008)the Humanities and Social Sciences Youth Funds of the Ministry of Education,China(Grant No.12YJCZH218)
文摘This paper is concerned with the stochastic bounded consensus tracking problems of leader-follower multi-agent systems, where the control input of an agent can only use the information measured at the sampling instants from its neighbours or the virtual leader with a time-varying reference state, and the measurements are corrupted by random noises. The probability limit theory and the algebra graph theory are employed to derive the necessary and sufficient conditions guaranteeing the mean square bounded consensus tracking. It is shown that the maximum allowable upper boundary of the sampling period simultaneously depends on the constant feedback gains and the network topology. Furthermore, the effects of the sampling period on the tracking performance are analysed. It turns out that from the view point of the sampling period, there is a trade-off between the tracking speed and the static tracking error. Simulations are provided to demonstrate the effectiveness of the theoretical results.
