Dear Editor,This letter investigates predefined-time optimization problems(OPs) of multi-agent systems(MASs), where the agent of MASs is subject to inequality constraints, and the team objective function accounts for ...Dear Editor,This letter investigates predefined-time optimization problems(OPs) of multi-agent systems(MASs), where the agent of MASs is subject to inequality constraints, and the team objective function accounts for impulse effects. Firstly, to address the inequality constraints,the penalty method is introduced. Then, a novel optimization strategy is developed, which only requires that the team objective function be strongly convex.展开更多
This paper investigates an innovative predefined time output feedback adaptive fuzzy consensus control method for fractional-order nonlinear multi-agent systems(FONMASs).The controlled system includes unmeasurable sta...This paper investigates an innovative predefined time output feedback adaptive fuzzy consensus control method for fractional-order nonlinear multi-agent systems(FONMASs).The controlled system includes unmeasurable states and unknown nonlinear functions.The fuzzy state observer is built to evaluate unmeasurable state variables,unknown nonlinear functions are addressed through fuzzy logic system approximation.Combining with fractional-order dynamic surface control(DSC)and the theory of stability of predefined time,the control method is raised.By employing FODSC techniques,the computational explosion problem can be avoided.The stability of the closed-loop system is analyzed using the Lyapunov function,demonstrating that FONMAS achieves semi-global practical predefined time stability(SGPPTS).Eventually,the validity of the prescribed control strategy is verified by a simulation case.展开更多
To overcome external environmental disturbances,inertial parameter uncertainties and vibration of flexible modes in the process of attitude tracking,a comprehensively effective predefined-time guaranteed performance c...To overcome external environmental disturbances,inertial parameter uncertainties and vibration of flexible modes in the process of attitude tracking,a comprehensively effective predefined-time guaranteed performance controller based on multi⁃observers for flexible spacecraft is proposed.First,to prevent unwinding phenomenon in attitude description,the rotation matrix is used to represent the spacecraft’s attitude.Second,the flexible modes observer which can guarantee predefined⁃time convergence is designed,for the case where flexible vibrations are unmeasurable in practice.What’s more,the disturbance observer is applied to estimate and compensate the lumped disturbances to improve the robustness of attitude control.A predefined-time controller is proposed to satisfy the prescribed performance and stabilize the attitude tracking system via barrier Lyapunov function.Finally,through comparative numerical simulations,the proposed controller can achieve high-precision convergence compared with the existing finite-time attitude tracking controller.This paper provides certain references for the high-precision predefined-time prescribed performance attitude tracking of flexible spacecraft with multi-disturbance.展开更多
This paper discusses the predefined practical finite-time(PPFT)dynamic positioning(DP)control problem for DP vessels subject to internal/external uncertainties.Those heterogeneity uncertainties are handled by a separa...This paper discusses the predefined practical finite-time(PPFT)dynamic positioning(DP)control problem for DP vessels subject to internal/external uncertainties.Those heterogeneity uncertainties are handled by a separate-type treatment approach.The finite-time(FT)DP control is fulfilled by a predefined FT function on the basis of a time-based generator(TBG).Under the dynamic surface control together with the TBG design framework,the convergence time and control accuracy of the DP system can be determined by the designer offline.Meanwhile,the virtual derivation and computational burden problems are dissolved by using a first-order filter and virtual parameter learning technique.To reduce mechanical wear,an event-triggering protocol between the control law and the actuator is built to reduce the operating frequency of the actuator.An event-triggered neuroadaptive PPFT control scheme is presented for DP vessels.The stability of the closed-loop DP control systems is validated via the Lyapunov theorem.Approach efficiency is confirmed by numerical examples.展开更多
基金supported in part by the National Natural Science Foundation of China(62276119)the Natural Science Foundation of Jiangsu Province(BK20241764)the Postgraduate Research & Practice Innovation Program of Jiangsu Province(KYCX22_2860)
文摘Dear Editor,This letter investigates predefined-time optimization problems(OPs) of multi-agent systems(MASs), where the agent of MASs is subject to inequality constraints, and the team objective function accounts for impulse effects. Firstly, to address the inequality constraints,the penalty method is introduced. Then, a novel optimization strategy is developed, which only requires that the team objective function be strongly convex.
基金funded in part by the National Natural Science Foundation of China under Grant Nos.62403226,62176111,and 62333004the Doctoral Research Initiation of Foundation of Liaoning Province,China under Grant No.2021-BS-260+5 种基金the general project of Liaoning Provincial Department of Education under Grant No.LIKZ0627Excellent Young Scientists Fund Program(Overseas)the“Xingliao Talent Plan”for young top talents under Grant No.XLYC22031882024 Fundamental Research Funding of the Educational Department of Liaoning Province under Grant No.LJZZ2224101540062024 Fundamental Research Funding of the Educational Department of Liaoning Province under Grant No.LJZZ2224101540012023 Education Department Basic Research Project(Youth Project)under Grant No.JYTQN2023225。
文摘This paper investigates an innovative predefined time output feedback adaptive fuzzy consensus control method for fractional-order nonlinear multi-agent systems(FONMASs).The controlled system includes unmeasurable states and unknown nonlinear functions.The fuzzy state observer is built to evaluate unmeasurable state variables,unknown nonlinear functions are addressed through fuzzy logic system approximation.Combining with fractional-order dynamic surface control(DSC)and the theory of stability of predefined time,the control method is raised.By employing FODSC techniques,the computational explosion problem can be avoided.The stability of the closed-loop system is analyzed using the Lyapunov function,demonstrating that FONMAS achieves semi-global practical predefined time stability(SGPPTS).Eventually,the validity of the prescribed control strategy is verified by a simulation case.
基金supported by the National Natural Science Foundation of China(No.12472045)the Shanghai Aerospace Science and Technology Innovation Fund(No.SAST2022-036)。
文摘To overcome external environmental disturbances,inertial parameter uncertainties and vibration of flexible modes in the process of attitude tracking,a comprehensively effective predefined-time guaranteed performance controller based on multi⁃observers for flexible spacecraft is proposed.First,to prevent unwinding phenomenon in attitude description,the rotation matrix is used to represent the spacecraft’s attitude.Second,the flexible modes observer which can guarantee predefined⁃time convergence is designed,for the case where flexible vibrations are unmeasurable in practice.What’s more,the disturbance observer is applied to estimate and compensate the lumped disturbances to improve the robustness of attitude control.A predefined-time controller is proposed to satisfy the prescribed performance and stabilize the attitude tracking system via barrier Lyapunov function.Finally,through comparative numerical simulations,the proposed controller can achieve high-precision convergence compared with the existing finite-time attitude tracking controller.This paper provides certain references for the high-precision predefined-time prescribed performance attitude tracking of flexible spacecraft with multi-disturbance.
基金supported in part by the National Natural Science Foundation of China(52022073,62073251 and 52261160383)in part by the Excellent Youth Foundation of Hubei Scientific Committee(2020CFA055)+4 种基金in part by the Natural Science Foundation of Zhejiang Province(LY21E090005)in part by the Innovation Research Team Project of the Hainan Natural Science Foundation(722CXTD518)in part by the Knowledge Innovation Program of Wuhan-Basic Research(2022010801010181)in part by the Science and Technology Project of Zhoushan(2022C41006)in part by the Hubei Key Laboratory of Inland Shipping Technology(NHHY2020004).
文摘This paper discusses the predefined practical finite-time(PPFT)dynamic positioning(DP)control problem for DP vessels subject to internal/external uncertainties.Those heterogeneity uncertainties are handled by a separate-type treatment approach.The finite-time(FT)DP control is fulfilled by a predefined FT function on the basis of a time-based generator(TBG).Under the dynamic surface control together with the TBG design framework,the convergence time and control accuracy of the DP system can be determined by the designer offline.Meanwhile,the virtual derivation and computational burden problems are dissolved by using a first-order filter and virtual parameter learning technique.To reduce mechanical wear,an event-triggering protocol between the control law and the actuator is built to reduce the operating frequency of the actuator.An event-triggered neuroadaptive PPFT control scheme is presented for DP vessels.The stability of the closed-loop DP control systems is validated via the Lyapunov theorem.Approach efficiency is confirmed by numerical examples.
