Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present so...Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present some sufficient conditions for the exponential stability of a particular category of switched systems.展开更多
This article investigates the time-varying output group formation tracking control(GFTC)problem for heterogeneous multi-agent systems(HMASs)under switching topologies.The objective is to design a distributed control s...This article investigates the time-varying output group formation tracking control(GFTC)problem for heterogeneous multi-agent systems(HMASs)under switching topologies.The objective is to design a distributed control strategy that enables the outputs of the followers to form the desired sub-formations and track the outputs of the leader in each subgroup.Firstly,novel distributed observers are developed to estimate the states of the leaders under switching topologies.Then,GFTC protocols are designed based on the proposed observers.It is shown that with the distributed protocol,the GFTC problem for HMASs under switching topologies is solved if the average dwell time associated with the switching topologies is larger than a fixed threshold.Finally,an example is provided to illustrate the effectiveness of the proposed control strategy.展开更多
The problem of satellite formation tracking control is studied by using the tool, the satellite tool kit （STK ） software.To fight against gravitational perturbation rejection, a sliding mode controller for each sate...The problem of satellite formation tracking control is studied by using the tool, the satellite tool kit （STK ） software.To fight against gravitational perturbation rejection, a sliding mode controller for each satellite is proposed to accomplish the orbit trace and is then verified by the STK.For the purpose of accomplishing the formation tracking mission with bidirectional communication in STK,a time-share orderly calling plug-in is designed by C ＋＋,which gives solutions to the problems of the monopolization of computing resource and no return of the satellite identifier in the calculation center. The effectiveness of the decoupling approach is tested and verified by the STK.The simulation results obtained by the STK are more meaningful than those obtained by Matlab.展开更多
This paper investigates a time-varying anti-disturbance formation problem for a group of quadrotor aircrafts with time-varying uncertainties and a directed interaction topology.A novel Finite-Time Convergent Extended ...This paper investigates a time-varying anti-disturbance formation problem for a group of quadrotor aircrafts with time-varying uncertainties and a directed interaction topology.A novel Finite-Time Convergent Extended State Observer(FTCESO)based fully-distributed formation control scheme is proposed to enhance the disturbance rejection and the formation tracking performances for networked quadrotors.By adopting the hierarchical control strategy,the multiquadrotor system is separated into two subsystems:the outer-loop cooperative subsystem and the inner-loop attitude subsystem.In the outer-loop subsystem,with the estimation of disturbing forces and uncertain dynamics from FTCESOs,an adaptive consensus theory based cooperative controller is exploited to ensure the multiple quadrotors form and maintain a time-varying pattern relying only on the positions of the neighboring aircrafts.In the inner-loop subsystem,the desired attitude generated by the cooperative control law is stably tracked under a FTCESO-based attitude controller in a finite time.Based on a detailed algorithm to specify the cooperative control protocol,the feasibility condition to achieve the time-varying anti-disturbance formation tracking is derived and the rigorous analysis of the whole closed-loop multi-quadrotor system is given.Some numerical examples are conducted to intuitively demonstrate the effectiveness and the improvements of the proposed control framework.展开更多
In this paper, formation tracking control problems for second-order multi-agent systems（MASs） with time-varying delays are studied, specifically those where the position and velocity of followers are designed to for...In this paper, formation tracking control problems for second-order multi-agent systems（MASs） with time-varying delays are studied, specifically those where the position and velocity of followers are designed to form a time-varying formation while tracking those of the leader. A neighboring relative state information based formation tracking protocol with an unknown gain matrix and time-varying delays is presented. The formation tracking problems are then transformed into asymptotically stable problems. Based on the Lyapunov-Krasovskii functional approach, conditions sufficient for second-order MASs with time-varying delays to realize formation tracking are examined. An approach to obtain the unknown gain matrix is given and, since neighboring relative velocity information is difficult to measure in practical applications, a formation tracking protocol with time-varying delays using only neighboring relative position information is introduced. The proposed results can be used on target enclosing problems for MASs with second-order dynamics and time-varying delays. An application for target enclosing by multiple unmanned aerial vehicles（UAVs） is given to demonstrate the feasibility of theoretical results.展开更多
In this study,the bipartite time-varying output formation tracking problem for heterogeneous multi-agent systems(MASs)with multiple leaders and switching commu-nication networks is considered.Note that the switching c...In this study,the bipartite time-varying output formation tracking problem for heterogeneous multi-agent systems(MASs)with multiple leaders and switching commu-nication networks is considered.Note that the switching communication networks may be connected or disconnected.To address this problem,a novel reduced-dimensional observer-based fully distributed asynchronous dynamic edge-event-triggered output feedback control protocol is developed,and the Zeno behavior is ruled out.The theoretical analysis gives the admissible switching frequency and switching width under the proposed control protocol.Different from the existing works,the control protocol reduces the dimension of information to be transmitted between neighboring agents.Moreover,since an additional positive internal dynamic variable is introduced into the triggering functions,the control protocol can guarantee a larger inter-event time interval compared with previous results.Finally,a simulation example is given to verify the effectiveness and performance of the theoretical result.展开更多
In recent years,multi-agent systems(MASs)formation tracking control(FTC)technology has achieved substantial advancements and has become a prominent research area due to its widespread applications in various fields,su...In recent years,multi-agent systems(MASs)formation tracking control(FTC)technology has achieved substantial advancements and has become a prominent research area due to its widespread applications in various fields,such as multi-unmanned aerial vehicle(multi-UAV)systems[1]and multiautonomous underwater vehicle(multi-AUV)systems[2].The consensusbased approach has evolved into the principal method for MASs’FTC because of its advantages,including rigorous logical deduction,easily solvable control parameters,and strong universal performance.展开更多
This paper presents a weight-based group formation tracking control method for air–ground multi-agent systems,where the system consists of unmanned aerial vehicles(UAVs)and unmanned ground vehicles(UGVs).Specifically...This paper presents a weight-based group formation tracking control method for air–ground multi-agent systems,where the system consists of unmanned aerial vehicles(UAVs)and unmanned ground vehicles(UGVs).Specifically,a three-layer directed communication topology consisting of a master leader,group leaders,and followers is designed first.Subsequently,a formation tracking controller is developed,and the stability of the system is proven using Lyapunov theory.Additionally,to address the collision issues that can arise during the grouping and flight of multi-UAV formations,a collision avoidance controller is designed based on a rotational potential field function.Finally,simulation experiments validate that the proposed method can achieve stable and safe grouping,formation,and collaborative tracking of air–ground multi-agent systems.展开更多
A novel adaptive output feedback control approach is presented for formation tracking of a multiagent system with uncertainties and quantized input signals. The agents are described by nonlinear dynamics models with u...A novel adaptive output feedback control approach is presented for formation tracking of a multiagent system with uncertainties and quantized input signals. The agents are described by nonlinear dynamics models with unknown parameters and immeasurable states. A high-gain dynamic state observer is established to estimate the immeasurable states. With a proper design parameter choice, an adaptive output feedback control method is developed employing a hysteretic quantizer and the designed dynamic state observer. Stability analysis shows that the control strategy can guarantee that the agents can maintain the formation shape while tracking the reference trajectory. In addition, all the signals in the closed-loop system are bounded. The effectiveness of the control strategy is validated by simulation.展开更多
Signal quantization can reduce communication burden in multi-agent systems,whereas it brings control challenge to multi-agent formation tracking.This paper studies the output feedback control problem for formation tra...Signal quantization can reduce communication burden in multi-agent systems,whereas it brings control challenge to multi-agent formation tracking.This paper studies the output feedback control problem for formation tracking of multi-agent systems with both quantized input and output.The agents are described by a nonlinear dynamic model with unknown parameters and immeasurable states.To estimate immeasurable states and solve the uncertainties,state observers are developed by using dynamic high-gain tools.Through proper parameter designs,an output feedback quantized controller is established based on quantized output signals,and the quantization effect on the control system is eliminated.Stability analysis proves that,with the proposed control scheme,multi-agent systems can track the reference trajectory while forming and maintaining the desired formation shape.In addition,all the signals in the closed-loop systems are bounded.Finally,the numerical simulation and practical experiment are provided to verify the theoretical analysis.展开更多
Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmann...Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmanned surface vehicles(USVs).We assume that each agent suffers from by the mixed constraints on its velocity,control input and Euler angle.Solving the MDFT problem implies that 1)The virtual state of each USV is determined in the earth coordinate by expanding its 2D work space to the 3D space.展开更多
Purpose–The purpose of this paper is to investigate the time-varying finite-time formation tracking control problem for multiple unmanned aerial vehicle systems under switching topologies,where the states of the unma...Purpose–The purpose of this paper is to investigate the time-varying finite-time formation tracking control problem for multiple unmanned aerial vehicle systems under switching topologies,where the states of the unmanned aerial vehicles need to form desired time-varying formations while tracking the trajectory of the virtual leader in finite time under jointly connected topologies.Design/methodology/approach–A consensus-based formation control protocol is constructed to achieve the desired formation.In this paper,the time-varying formation is specified by a piecewise continuously differentiable vector,while the finite-time convergence is guaranteed by utilizing a non-linear function.Based on the graph theory,the finite-time stability of the close-loop system with the proposed control protocol under jointly connected topologies is proven by applying LaSalle’s invariance principle and the theory of homogeneity with dilation.Findings–The effectiveness of the proposed protocol is verified by numerical simulations.Consequently,the proposed protocol can successfully achieve the predefined time-varying formation in finite time under jointly connected topologies while tracking the trajectory generated by the leader.Originality/value–This paper proposes a solution to simultaneously solve the control problems of time-varying formation tracking,finite-time convergence,and switching topologies.展开更多
In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector def...In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector definition,are presented in order to describe the flight state and construct the desired relative velocity.Then,the relative kinematic model between the UAV and the moving target is established.The distributed control law is constructed by using dynamic feedback linearization so as to realize the tracking and circumnavigating control with the desired velocity,circing radius and relative angular spacing.Next,the exponential stability of the closed-loop system is further guaranteed by properly choosing some corresponding parameters based on the Lyapunov method.Finally,the numerical simulation is caried out to verify the effectiveness of the proposed control method.展开更多
基金supported in part by the National Natural Science Foundation of China(62273255,62350003,62088101)the Shanghai Science and Technology Cooperation Project(22510712000,21550760900)+1 种基金the Shanghai Municipal Science and Technology Major Project(2021SHZDZX0100)the Fundamental Research Funds for the Central Universities
文摘Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present some sufficient conditions for the exponential stability of a particular category of switched systems.
文摘This article investigates the time-varying output group formation tracking control(GFTC)problem for heterogeneous multi-agent systems(HMASs)under switching topologies.The objective is to design a distributed control strategy that enables the outputs of the followers to form the desired sub-formations and track the outputs of the leader in each subgroup.Firstly,novel distributed observers are developed to estimate the states of the leaders under switching topologies.Then,GFTC protocols are designed based on the proposed observers.It is shown that with the distributed protocol,the GFTC problem for HMASs under switching topologies is solved if the average dwell time associated with the switching topologies is larger than a fixed threshold.Finally,an example is provided to illustrate the effectiveness of the proposed control strategy.
基金The National Natural Science Foundation of China(No.61203356,61473081,61374069)the Ph.D.Programs Foundation of Ministry of Education of China(No.20110092120025)+1 种基金the Open Fund of Key Laboratory of Measurement and Control of Complex Systems of Engineering of Ministry of Education(No.MCCSE2014B01)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The problem of satellite formation tracking control is studied by using the tool, the satellite tool kit （STK ） software.To fight against gravitational perturbation rejection, a sliding mode controller for each satellite is proposed to accomplish the orbit trace and is then verified by the STK.For the purpose of accomplishing the formation tracking mission with bidirectional communication in STK,a time-share orderly calling plug-in is designed by C ＋＋,which gives solutions to the problems of the monopolization of computing resource and no return of the satellite identifier in the calculation center. The effectiveness of the decoupling approach is tested and verified by the STK.The simulation results obtained by the STK are more meaningful than those obtained by Matlab.
文摘This paper investigates a time-varying anti-disturbance formation problem for a group of quadrotor aircrafts with time-varying uncertainties and a directed interaction topology.A novel Finite-Time Convergent Extended State Observer(FTCESO)based fully-distributed formation control scheme is proposed to enhance the disturbance rejection and the formation tracking performances for networked quadrotors.By adopting the hierarchical control strategy,the multiquadrotor system is separated into two subsystems:the outer-loop cooperative subsystem and the inner-loop attitude subsystem.In the outer-loop subsystem,with the estimation of disturbing forces and uncertain dynamics from FTCESOs,an adaptive consensus theory based cooperative controller is exploited to ensure the multiple quadrotors form and maintain a time-varying pattern relying only on the positions of the neighboring aircrafts.In the inner-loop subsystem,the desired attitude generated by the cooperative control law is stably tracked under a FTCESO-based attitude controller in a finite time.Based on a detailed algorithm to specify the cooperative control protocol,the feasibility condition to achieve the time-varying anti-disturbance formation tracking is derived and the rigorous analysis of the whole closed-loop multi-quadrotor system is given.Some numerical examples are conducted to intuitively demonstrate the effectiveness and the improvements of the proposed control framework.
基金co-supported by the National Natural Science Foundation of China (Nos. 61333011, 91216304 and 61121003)
文摘In this paper, formation tracking control problems for second-order multi-agent systems（MASs） with time-varying delays are studied, specifically those where the position and velocity of followers are designed to form a time-varying formation while tracking those of the leader. A neighboring relative state information based formation tracking protocol with an unknown gain matrix and time-varying delays is presented. The formation tracking problems are then transformed into asymptotically stable problems. Based on the Lyapunov-Krasovskii functional approach, conditions sufficient for second-order MASs with time-varying delays to realize formation tracking are examined. An approach to obtain the unknown gain matrix is given and, since neighboring relative velocity information is difficult to measure in practical applications, a formation tracking protocol with time-varying delays using only neighboring relative position information is introduced. The proposed results can be used on target enclosing problems for MASs with second-order dynamics and time-varying delays. An application for target enclosing by multiple unmanned aerial vehicles（UAVs） is given to demonstrate the feasibility of theoretical results.
基金supported by National Key R&D Program of China(2018YFA0702200)the National Natural Science Foundation of China(61627809, 62173080)Liaoning Revitalization Talents Program(XLYC1801005)
文摘In this study,the bipartite time-varying output formation tracking problem for heterogeneous multi-agent systems(MASs)with multiple leaders and switching commu-nication networks is considered.Note that the switching communication networks may be connected or disconnected.To address this problem,a novel reduced-dimensional observer-based fully distributed asynchronous dynamic edge-event-triggered output feedback control protocol is developed,and the Zeno behavior is ruled out.The theoretical analysis gives the admissible switching frequency and switching width under the proposed control protocol.Different from the existing works,the control protocol reduces the dimension of information to be transmitted between neighboring agents.Moreover,since an additional positive internal dynamic variable is introduced into the triggering functions,the control protocol can guarantee a larger inter-event time interval compared with previous results.Finally,a simulation example is given to verify the effectiveness and performance of the theoretical result.
基金supported by the National Science Fund for Distinguished Young Scholars(62425304)the National Key Laboratory of Air-based Information Perception and Fusion and the Aeronautical Science Foundation of China(Grant No.20220001068001)the Ganzhou Key Laboratory of Smart Integrated Photovoltaic-Charging-Storage Energy System(Grant No.2024YSPT0010)。
文摘In recent years,multi-agent systems(MASs)formation tracking control(FTC)technology has achieved substantial advancements and has become a prominent research area due to its widespread applications in various fields,such as multi-unmanned aerial vehicle(multi-UAV)systems[1]and multiautonomous underwater vehicle(multi-AUV)systems[2].The consensusbased approach has evolved into the principal method for MASs’FTC because of its advantages,including rigorous logical deduction,easily solvable control parameters,and strong universal performance.
基金supported by the National Natural Science Foundation of China(Grant No.62173242)the Major Science and Technology Plan Project of Hainan(Grant No.ZDKJ2021057)the National Science Fund for Distinguished Young Scholars(Grant No.62225308)
文摘This paper presents a weight-based group formation tracking control method for air–ground multi-agent systems,where the system consists of unmanned aerial vehicles(UAVs)and unmanned ground vehicles(UGVs).Specifically,a three-layer directed communication topology consisting of a master leader,group leaders,and followers is designed first.Subsequently,a formation tracking controller is developed,and the stability of the system is proven using Lyapunov theory.Additionally,to address the collision issues that can arise during the grouping and flight of multi-UAV formations,a collision avoidance controller is designed based on a rotational potential field function.Finally,simulation experiments validate that the proposed method can achieve stable and safe grouping,formation,and collaborative tracking of air–ground multi-agent systems.
基金supported by the National Natural Science Foundation of China(No.20155896025)
文摘A novel adaptive output feedback control approach is presented for formation tracking of a multiagent system with uncertainties and quantized input signals. The agents are described by nonlinear dynamics models with unknown parameters and immeasurable states. A high-gain dynamic state observer is established to estimate the immeasurable states. With a proper design parameter choice, an adaptive output feedback control method is developed employing a hysteretic quantizer and the designed dynamic state observer. Stability analysis shows that the control strategy can guarantee that the agents can maintain the formation shape while tracking the reference trajectory. In addition, all the signals in the closed-loop system are bounded. The effectiveness of the control strategy is validated by simulation.
基金supported by the Aeronautical Science Foundation of China under Grant No.20155896025。
文摘Signal quantization can reduce communication burden in multi-agent systems,whereas it brings control challenge to multi-agent formation tracking.This paper studies the output feedback control problem for formation tracking of multi-agent systems with both quantized input and output.The agents are described by a nonlinear dynamic model with unknown parameters and immeasurable states.To estimate immeasurable states and solve the uncertainties,state observers are developed by using dynamic high-gain tools.Through proper parameter designs,an output feedback quantized controller is established based on quantized output signals,and the quantization effect on the control system is eliminated.Stability analysis proves that,with the proposed control scheme,multi-agent systems can track the reference trajectory while forming and maintaining the desired formation shape.In addition,all the signals in the closed-loop systems are bounded.Finally,the numerical simulation and practical experiment are provided to verify the theoretical analysis.
基金supported in part by the National Natural Science Foundation of China(62073301,62373162,62473349,U24A20268,62233007)the Shenzhen Science and Technology Program(JCYJ20240813114007010).
文摘Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmanned surface vehicles(USVs).We assume that each agent suffers from by the mixed constraints on its velocity,control input and Euler angle.Solving the MDFT problem implies that 1)The virtual state of each USV is determined in the earth coordinate by expanding its 2D work space to the 3D space.
基金This work is supported by NNSFC Nos 61603383 and CXJJ-16Z212.
文摘Purpose–The purpose of this paper is to investigate the time-varying finite-time formation tracking control problem for multiple unmanned aerial vehicle systems under switching topologies,where the states of the unmanned aerial vehicles need to form desired time-varying formations while tracking the trajectory of the virtual leader in finite time under jointly connected topologies.Design/methodology/approach–A consensus-based formation control protocol is constructed to achieve the desired formation.In this paper,the time-varying formation is specified by a piecewise continuously differentiable vector,while the finite-time convergence is guaranteed by utilizing a non-linear function.Based on the graph theory,the finite-time stability of the close-loop system with the proposed control protocol under jointly connected topologies is proven by applying LaSalle’s invariance principle and the theory of homogeneity with dilation.Findings–The effectiveness of the proposed protocol is verified by numerical simulations.Consequently,the proposed protocol can successfully achieve the predefined time-varying formation in finite time under jointly connected topologies while tracking the trajectory generated by the leader.Originality/value–This paper proposes a solution to simultaneously solve the control problems of time-varying formation tracking,finite-time convergence,and switching topologies.
基金supported in part by the National Natural Science Foundation of China(61703081,62173082)the Liaoning Joint Fund of National Natural Science Foundation of China(U1908217)+2 种基金the Liaoning Revitalization Talents Program(XLYC1801005)Natural Science Foundation of Liaoning Province(20170520113)and the Fundamental Research Funds for the Central Universities(N2004016).
文摘In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector definition,are presented in order to describe the flight state and construct the desired relative velocity.Then,the relative kinematic model between the UAV and the moving target is established.The distributed control law is constructed by using dynamic feedback linearization so as to realize the tracking and circumnavigating control with the desired velocity,circing radius and relative angular spacing.Next,the exponential stability of the closed-loop system is further guaranteed by properly choosing some corresponding parameters based on the Lyapunov method.Finally,the numerical simulation is caried out to verify the effectiveness of the proposed control method.
