We describe a single sided matrix converter (SSMC) designed for safety critical applications like flight control actuation systems. Dynamic simulations of multi-phase SSMC using Matlab Simulink are carried out to eval...We describe a single sided matrix converter (SSMC) designed for safety critical applications like flight control actuation systems. Dynamic simulations of multi-phase SSMC using Matlab Simulink are carried out to evaluate the fault tolerance capabilities. Investigation into different numbers of phases and power converter topologies under single phase open circuit, single switch open circuit, and single switch short circuit has been executed. The simulation results confirm 5-phase SSMC design as a compromise between fault tolerance and converter size/volume. A 5-phase SSMC prototype was built. Experimental results verify the effectiveness of our design.展开更多
Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectiv...Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system.展开更多
This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates senso...This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates sensor and actuator disturbances within the dynamics of follower robots.Each follower robot has unknown dynamics and control inputs,which expose it to the risks of both sensor and actuator attacks.The leader robot,described by a secondorder,time-varying nonlinear model,transmits its position,velocity,and acceleration information to follower robots through a wireless connection.To handle the complex setup and communication among robots in the network,we design a robust hybrid distributed adaptive control strategy combining the effect of sensor and actuator attack,which ensures asymptotic consensus,extending beyond conventional bounded consensus results.The proposed framework employs fuzzy logic systems(FLSs)as proactive controllers to estimate unknown nonlinear behaviors,while also effectively managing sensor and actuator attacks,ensuring stable consensus among all agents.To counter the impact of the combined signal attack on follower dynamics,a specialized robust control mechanism is designed,sustaining system stability and performance under adversarial conditions.The efficiency of this control strategy is demonstrated through simulations conducted across two different directed communication topologies,underscoring the protocol’s adaptability,resilience,and effectiveness in maintaining global consensus under complex attack scenarios.展开更多
This paper presents a robust adaptive state feedback control scheme for a class of parametric-strict-feedback nonlinear systems in the presence of time varying actuator failures. The designed adaptive controller compe...This paper presents a robust adaptive state feedback control scheme for a class of parametric-strict-feedback nonlinear systems in the presence of time varying actuator failures. The designed adaptive controller compensates a general class of actuator failures without any need for explicit fault detection. The parameters, times, and patterns of the considered failures are completely unknown. The proposed controller is constructed based on a backstepping design method. The global boundedness of all the closed-loop signals is guaranteed and the tracking error is proved to converge to a small neighborhood of the origin. The proposed approach is employed for a two-axis positioning stage system as well as an aircraft wing system. The simulation results show the correctness and effectiveness of the proposed robust adaptive actuator failure compensation approach.展开更多
A new approach to fault dignosis dealing with nonlinear system Hopfieldneural networks (HNN) is presented. The model parameters of the nonlinear systemtreated as functions of measured operating points and faults are e...A new approach to fault dignosis dealing with nonlinear system Hopfieldneural networks (HNN) is presented. The model parameters of the nonlinear systemtreated as functions of measured operating points and faults are estimated by HNN. Boththe nominal model of the healthy system and HNN training models corresponding to everyoperating point are recognized. In addition, the anticipated fault models corresponding toevery kind of fault and every operating point are obtaind in advance. The real systemmodel parameters of the system estimated by generalization process of HNN are matchedwith the nominal models of the healthy system and anticipated fault models. Consequent-ly, the final result of fault detection and diagnosis is acquired. The approach to fault diag-nosis is used in an aircraft actuating poisition servo system and the simulation resu1t is re-ported.展开更多
This paper thoroughly investigates adaptive stabilisation for a specific class of second-order strict-feedback nonlinear systems.Drawing inspiration from the fully actuated system(FAS)approach,an adaptive control sche...This paper thoroughly investigates adaptive stabilisation for a specific class of second-order strict-feedback nonlinear systems.Drawing inspiration from the fully actuated system(FAS)approach,an adaptive control scheme incorporating FAS with tuning functions is proposed.Notably,this approach directly addresses second-order systems without the need for reducing them to first-order systems,streamlining the intricate procedures involved.To handle uncertain parameters within the system,a combined scheme of adaptive estimation and tuning functions is employed.Rigorous analysis using Lyapunov stability theory demonstrates that the designed controller ensures the system's asymptotic convergence to the equilibrium point,with all other signals in the closed-loop system bounded.Finally,two simulation experiments verify the effectiveness of the proposed strategy:numerical simulations compared with sliding mode control and backstepping control,and practical application on the single-link robotic arm with a comparative analysis against backstepping control.展开更多
In this paper,the prescribed error trajectory control is proposed for second-order fully actuated systems.At first,by taking advantage of the full-actuation property,an intermediate control law is designed such that t...In this paper,the prescribed error trajectory control is proposed for second-order fully actuated systems.At first,by taking advantage of the full-actuation property,an intermediate control law is designed such that the intermediate closed-loop system is in a very simple form.Then,by utilizing the initial conditions of system states and the prescribed error performance function,the intermediate control law is developed to force the tracking error of the system on the proposed sliding mode surface from the beginning.The overall control law is obtained by combining the aforementioned steps.It is revealed that under the designed control law,the tracking error of the closed-loop system converges to zero along the prescribed error trajectory.Finally,an example is provided to validate the effectiveness of the presented approach.展开更多
It is well known that for a linear system in state space form,controllability is equivalent to arbitrary pole assignment by state feedback.This brief points out that for a scalar high-order fully actuated linear syste...It is well known that for a linear system in state space form,controllability is equivalent to arbitrary pole assignment by state feedback.This brief points out that for a scalar high-order fully actuated linear system,the pole assignment problem is solvable if and only if the desired pole set of the closed-loop system should not include the zero set of the open-loop system if the implementation issue of the controller is taken into account,that is,controllability cannot guarantee arbitrary pole assignment by state feedback.展开更多
This paper investigates the control problem of high-order fully actuated nonlinear systems with time-varying delays in the discrete-time domain.To make the compensation for time-varying delays concise,active and unive...This paper investigates the control problem of high-order fully actuated nonlinear systems with time-varying delays in the discrete-time domain.To make the compensation for time-varying delays concise,active and universal,a novel nonlinear predictive control method is proposed.The designed nonlinear predictive controller can achieve the same expected control performance as the nonlinear systems without delays.At the same time,the necessary and sufficient conditions for the stability of the closed-loop nonlinear predictive control systems are derived.Numerical examples show that the proposed nonlinear predictive controller design method can completely compensate for the time-varying delays of nonlinear systems.展开更多
This note studies fully actuated linear systems in the frequency domain in terms of polynomial matrix description(PMD).For a controllable first-order linear state-space system model,by using the right coprime factoriz...This note studies fully actuated linear systems in the frequency domain in terms of polynomial matrix description(PMD).For a controllable first-order linear state-space system model,by using the right coprime factorization of its transfer function matrix,under the condition that the denominator matrix in the right coprime factorization is column reduced,it is equivalently transformed into a fully actuated PMD model,whose time-domain expression is just a high-order fully actuated(HOFA)system model.This method is a supplement to the previous one in the time-domain,and reveals a connection between the controllability of the first-order linear state-space system model and the fullactuation of its PMD model.Both continuous-time and discrete-time linear systems are considered.Some numerical examples are worked out to illustrate the effectiveness of the proposed approaches.展开更多
For a class of second-order sub-fully actuated systems(SOSFASs),this paper presents a preset-trajectory-based(PT-based)adaptive stabilising control method by integrating the function augmented sliding mode control(FAS...For a class of second-order sub-fully actuated systems(SOSFASs),this paper presents a preset-trajectory-based(PT-based)adaptive stabilising control method by integrating the function augmented sliding mode control(FASMC)technique and the flat-zone introduced Lyapunov function technique.The SOSFASs under study are subject to internal uncertainties and external disturbances.The proposed PT-based stabilising control method exhibits several attractive features:1)The system states can converge to a predefined region close to zero in a preassigned time and can be confined in a preassigned‘safe’area,which can make the control coefficient matrix always full rank so as to preserve the realizability of the proposed controller;2)the utilization of flat-zone introduced Lyapunov function technique not only eliminates the chatting phenomenon,but also avoids the potential persistent increase problem of the adaptive law;and 3)the control gain increases as the adaptive law increases only when necessary,that is,when the current control gain is not sufficient to suppress uncertainties or disturbances,therefore,the conservativeness of the control design due to unnecessarily high control gain can be effectively reduced.The effectiveness of the proposed control method is verified via a numerical example.展开更多
The article is devoted to the almost disturbance decoupling problem for high-order fully actuated(HOFA)nonlinear systems with strict-feedback form.Using the full-actuation feature of high-order fully actuated systems ...The article is devoted to the almost disturbance decoupling problem for high-order fully actuated(HOFA)nonlinear systems with strict-feedback form.Using the full-actuation feature of high-order fully actuated systems and Lyapunov stability theory,a state feedback control law and virtual control laws are designed.The unknown disturbances are handled by almost disturbance decoupling(ADD)method.Finally,the effectiveness of the control strategy is verified by stability analysis and simulation.展开更多
In this paper,the problem of guaranteed cost control and anti-windup design is studied for a class of switched systems with actuator saturation.The switching strategy and anti-windup compensator are designed to ensure...In this paper,the problem of guaranteed cost control and anti-windup design is studied for a class of switched systems with actuator saturation.The switching strategy and anti-windup compensator are designed to ensure the asymptotic stability of the closed-loop system and to obtain the minimum upper bound of the cost function.Some sufficient conditions for the existence of an anti-windup compensator of guaranteed cost are given by using the multiple Lyapunov functions method.On this basis,the minimum upper bound of the cost function is determined by solving the optimisation problem under the constraint of linear matrix inequality(LMI).Finally,a numerical example is given to verify the effectiveness of the proposed method.展开更多
Magnetic soft robots are emerging as a promising technology in biomedical applications, offering precise, minimally invasive solutions for clinical procedures. Magnetic soft robots, often constructed by using magnetic...Magnetic soft robots are emerging as a promising technology in biomedical applications, offering precise, minimally invasive solutions for clinical procedures. Magnetic soft robots, often constructed by using magnetic particles embedded in flexible polymers, exhibit enhanced deformability and maneuverability, particularly at micro and nanoscale levels. This paper provides a comprehensive overview of the design, fabrication, and medical applications of these robots, focusing on the synthesis of magnetic materials, structural configurations, and actuation mechanisms. Structural designs are summarized, from simple one-dimensional forms to complex, multi-dimensional structures inspired by origami and kirigami principles. Additionally, magnetic actuation systems, including permanent magnets and electromagnetic coils, are examined for their respective roles in achieving the required precision or field strength for medical use. The potential applications in medicine are vast, ranging from targeted drug delivery and minimally invasive surgeries to disease diagnosis and treatment, with specific examples in tumor targeting, Alzheimer's therapy, and endodontics. The paper also addresses emerging applications in assisted reproduction and microbiota regulation. Despite challenges related to power supply, real-time tracking, and material safety, the review highlights the significant potential of magnetic soft robots to revolutionize healthcare practices.展开更多
This paper presents a gain-scheduling model predictive control(MPC) for linear parameter varying(LPV) systems subject to actuator saturation. The proposed gain-scheduling MPC algorithm is then applied to the lateral c...This paper presents a gain-scheduling model predictive control(MPC) for linear parameter varying(LPV) systems subject to actuator saturation. The proposed gain-scheduling MPC algorithm is then applied to the lateral control of unmanned airship.The unmanned airship is modeled by an LPV-type system and transformed into a polytopic uncertain description with actuator saturation. By introducing a parameter-dependent state feedback law, the set invariance condition of the polytopic uncertain system is identified. Based on the invariant set, the gain-scheduling MPC controller is presented by solving a linear matrix inequality(LMI) optimization problem. The proposed gain-scheduling MPC algorithm is demonstrated by simulating on the unmanned airship system.展开更多
This paper focuses on the trajectory tracking control problem of unmanned underwater vehicles(UUVs)with unknown dead-zone inputs.The primary objective is to design an adaptive trajectory tracking error constraint cont...This paper focuses on the trajectory tracking control problem of unmanned underwater vehicles(UUVs)with unknown dead-zone inputs.The primary objective is to design an adaptive trajectory tracking error constraint controller using the fully actuated systems(FAs)approach to enable UUVs to asymptotically track target signals.Firstly,a novel error constraint fully actuated systems(ECFAs)approach is proposed by incorporating the tracking error dependent normalized function and barrier function along with time-varying scaling.Secondly,in order to deal with the model uncertainties of the UUVs,adaptive radial basis function neural networks(RBFNNs)is combined with the ECFAs approach.Then,a positive time-varying integral function is introduced to completely eliminate the effect of the residual effect caused by unknown dead-zone inputs,and it is proved that the trajectory tracking error converges to zero asymptotically based on the Lyapunov functions.Finally,the simulation results demonstrate the effectiveness of the designed adaptive controller.展开更多
In this paper,a fully actuated system approach(FASA)-based control scheme is proposed for the trajectory tracking of a quadrotor unmanned aerial vehicle(UAV).System uncertainty,external disturbance and actuator constr...In this paper,a fully actuated system approach(FASA)-based control scheme is proposed for the trajectory tracking of a quadrotor unmanned aerial vehicle(UAV).System uncertainty,external disturbance and actuator constraint are all considered,which make the problem challenging.Inspired by the active disturbance rejection control(ADRC),tracking di®erentiator(TD)and extended state observer(ESO)are introduced for handling the uncertainties and generating the feedback signals.With the proposed feedback control law,the performance of the resulted closed loop system is related to its eigenstructure-eigenvalue and eigenvectors.Based on a type of control parametrization method,the parametrized eigenstructure of the closed loop system are optimized.A better performance is observed by comparative numerical simulation.展开更多
基金supported by the UK government under the DTI CARAD programthe National Natural Science Foundation of China (No.51007078)+1 种基金the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (No.2009BAG12A05)the National High-Tech R&D (863) Program of China (No. 2011AA11A101)
文摘We describe a single sided matrix converter (SSMC) designed for safety critical applications like flight control actuation systems. Dynamic simulations of multi-phase SSMC using Matlab Simulink are carried out to evaluate the fault tolerance capabilities. Investigation into different numbers of phases and power converter topologies under single phase open circuit, single switch open circuit, and single switch short circuit has been executed. The simulation results confirm 5-phase SSMC design as a compromise between fault tolerance and converter size/volume. A 5-phase SSMC prototype was built. Experimental results verify the effectiveness of our design.
基金supported in part by the National Natural Science Foundation of China(62173255,62188101)Shenzhen Key Laboratory of Control Theory and Intelligent Systems(ZDSYS20220330161800001)
文摘Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system.
文摘This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates sensor and actuator disturbances within the dynamics of follower robots.Each follower robot has unknown dynamics and control inputs,which expose it to the risks of both sensor and actuator attacks.The leader robot,described by a secondorder,time-varying nonlinear model,transmits its position,velocity,and acceleration information to follower robots through a wireless connection.To handle the complex setup and communication among robots in the network,we design a robust hybrid distributed adaptive control strategy combining the effect of sensor and actuator attack,which ensures asymptotic consensus,extending beyond conventional bounded consensus results.The proposed framework employs fuzzy logic systems(FLSs)as proactive controllers to estimate unknown nonlinear behaviors,while also effectively managing sensor and actuator attacks,ensuring stable consensus among all agents.To counter the impact of the combined signal attack on follower dynamics,a specialized robust control mechanism is designed,sustaining system stability and performance under adversarial conditions.The efficiency of this control strategy is demonstrated through simulations conducted across two different directed communication topologies,underscoring the protocol’s adaptability,resilience,and effectiveness in maintaining global consensus under complex attack scenarios.
基金supported by Esfahan Regional Electric Company(EREC)
文摘This paper presents a robust adaptive state feedback control scheme for a class of parametric-strict-feedback nonlinear systems in the presence of time varying actuator failures. The designed adaptive controller compensates a general class of actuator failures without any need for explicit fault detection. The parameters, times, and patterns of the considered failures are completely unknown. The proposed controller is constructed based on a backstepping design method. The global boundedness of all the closed-loop signals is guaranteed and the tracking error is proved to converge to a small neighborhood of the origin. The proposed approach is employed for a two-axis positioning stage system as well as an aircraft wing system. The simulation results show the correctness and effectiveness of the proposed robust adaptive actuator failure compensation approach.
文摘A new approach to fault dignosis dealing with nonlinear system Hopfieldneural networks (HNN) is presented. The model parameters of the nonlinear systemtreated as functions of measured operating points and faults are estimated by HNN. Boththe nominal model of the healthy system and HNN training models corresponding to everyoperating point are recognized. In addition, the anticipated fault models corresponding toevery kind of fault and every operating point are obtaind in advance. The real systemmodel parameters of the system estimated by generalization process of HNN are matchedwith the nominal models of the healthy system and anticipated fault models. Consequent-ly, the final result of fault detection and diagnosis is acquired. The approach to fault diag-nosis is used in an aircraft actuating poisition servo system and the simulation resu1t is re-ported.
基金supported in part by the China Postdoctoral Science Foundation[grant number 2022M721902]in part by the Guangyue Young Scholar Innovation Team of Liaocheng University[grant number LCUGYTD2022-01]+1 种基金in part by the Liaocheng University Major Vertical Project Cultivation Plan Project[grant number 318062305]in part by the Science Center Program of National Natural Science Foundation of China[grant number 62188101].
文摘This paper thoroughly investigates adaptive stabilisation for a specific class of second-order strict-feedback nonlinear systems.Drawing inspiration from the fully actuated system(FAS)approach,an adaptive control scheme incorporating FAS with tuning functions is proposed.Notably,this approach directly addresses second-order systems without the need for reducing them to first-order systems,streamlining the intricate procedures involved.To handle uncertain parameters within the system,a combined scheme of adaptive estimation and tuning functions is employed.Rigorous analysis using Lyapunov stability theory demonstrates that the designed controller ensures the system's asymptotic convergence to the equilibrium point,with all other signals in the closed-loop system bounded.Finally,two simulation experiments verify the effectiveness of the proposed strategy:numerical simulations compared with sliding mode control and backstepping control,and practical application on the single-link robotic arm with a comparative analysis against backstepping control.
基金This paper was supported by the Science Center Program of the National Natural Science Foundation of China under Grant No.62188101the Joint Funds of the National Natural Science Foundation of China under Grant No.U2013203.
文摘In this paper,the prescribed error trajectory control is proposed for second-order fully actuated systems.At first,by taking advantage of the full-actuation property,an intermediate control law is designed such that the intermediate closed-loop system is in a very simple form.Then,by utilizing the initial conditions of system states and the prescribed error performance function,the intermediate control law is developed to force the tracking error of the system on the proposed sliding mode surface from the beginning.The overall control law is obtained by combining the aforementioned steps.It is revealed that under the designed control law,the tracking error of the closed-loop system converges to zero along the prescribed error trajectory.Finally,an example is provided to validate the effectiveness of the presented approach.
基金supported by the National Science Fund for Distinguished Young Scholars under Grant No.62125303the Science Center Program of National Natural Science Foundation of China under Grant No.62188101.
文摘It is well known that for a linear system in state space form,controllability is equivalent to arbitrary pole assignment by state feedback.This brief points out that for a scalar high-order fully actuated linear system,the pole assignment problem is solvable if and only if the desired pole set of the closed-loop system should not include the zero set of the open-loop system if the implementation issue of the controller is taken into account,that is,controllability cannot guarantee arbitrary pole assignment by state feedback.
基金This research was supported in part by the National Natural Science Foundation of China under Grant Nos.62173255 and 62188101.
文摘This paper investigates the control problem of high-order fully actuated nonlinear systems with time-varying delays in the discrete-time domain.To make the compensation for time-varying delays concise,active and universal,a novel nonlinear predictive control method is proposed.The designed nonlinear predictive controller can achieve the same expected control performance as the nonlinear systems without delays.At the same time,the necessary and sufficient conditions for the stability of the closed-loop nonlinear predictive control systems are derived.Numerical examples show that the proposed nonlinear predictive controller design method can completely compensate for the time-varying delays of nonlinear systems.
基金the Science Center Program of the National Natural Science Foundation of China under Grant No.62188101the Major Program of National Natural Science Foundation of China under Grant Nos.61690210 and 61690212+1 种基金the National Natural Science Foundation of China under Grant No.61333003the Self-Planned Task of State Key Laboratory of Robotics and System(HIT)under Grant No.SKLRS201716A。
文摘This note studies fully actuated linear systems in the frequency domain in terms of polynomial matrix description(PMD).For a controllable first-order linear state-space system model,by using the right coprime factorization of its transfer function matrix,under the condition that the denominator matrix in the right coprime factorization is column reduced,it is equivalently transformed into a fully actuated PMD model,whose time-domain expression is just a high-order fully actuated(HOFA)system model.This method is a supplement to the previous one in the time-domain,and reveals a connection between the controllability of the first-order linear state-space system model and the fullactuation of its PMD model.Both continuous-time and discrete-time linear systems are considered.Some numerical examples are worked out to illustrate the effectiveness of the proposed approaches.
基金supported by the National Natural Science Foundation of China under Grant No.62073096the Science Center Program of National Natural Science Foundation of China under Grant No.62188101the Heilongjiang Touyan Team Program.
文摘For a class of second-order sub-fully actuated systems(SOSFASs),this paper presents a preset-trajectory-based(PT-based)adaptive stabilising control method by integrating the function augmented sliding mode control(FASMC)technique and the flat-zone introduced Lyapunov function technique.The SOSFASs under study are subject to internal uncertainties and external disturbances.The proposed PT-based stabilising control method exhibits several attractive features:1)The system states can converge to a predefined region close to zero in a preassigned time and can be confined in a preassigned‘safe’area,which can make the control coefficient matrix always full rank so as to preserve the realizability of the proposed controller;2)the utilization of flat-zone introduced Lyapunov function technique not only eliminates the chatting phenomenon,but also avoids the potential persistent increase problem of the adaptive law;and 3)the control gain increases as the adaptive law increases only when necessary,that is,when the current control gain is not sufficient to suppress uncertainties or disturbances,therefore,the conservativeness of the control design due to unnecessarily high control gain can be effectively reduced.The effectiveness of the proposed control method is verified via a numerical example.
基金This research was supported by the Taishan Scholar Project of Shandong Province of China under Grant Nos.2015162 and tsqn201812093.
文摘The article is devoted to the almost disturbance decoupling problem for high-order fully actuated(HOFA)nonlinear systems with strict-feedback form.Using the full-actuation feature of high-order fully actuated systems and Lyapunov stability theory,a state feedback control law and virtual control laws are designed.The unknown disturbances are handled by almost disturbance decoupling(ADD)method.Finally,the effectiveness of the control strategy is verified by stability analysis and simulation.
基金the Natural Science Foundation of Liaoning Province of China[grant numbers 2020-MS-283 and 20180551014]the Scientific Research Fund of Education Department of Liaoning Province of China[grant number L2019016].
文摘In this paper,the problem of guaranteed cost control and anti-windup design is studied for a class of switched systems with actuator saturation.The switching strategy and anti-windup compensator are designed to ensure the asymptotic stability of the closed-loop system and to obtain the minimum upper bound of the cost function.Some sufficient conditions for the existence of an anti-windup compensator of guaranteed cost are given by using the multiple Lyapunov functions method.On this basis,the minimum upper bound of the cost function is determined by solving the optimisation problem under the constraint of linear matrix inequality(LMI).Finally,a numerical example is given to verify the effectiveness of the proposed method.
基金support from Natural Science Foundation of China(No.52475030)supported by the National Key R&D Project of China(2023YFF0713700,YL)+1 种基金the Young Talent fund of University Association for Science and Technology in Shaanxi,China(No.20230302)Xi'an Science and Technology Plan Project(No.24YXYJ0161).
文摘Magnetic soft robots are emerging as a promising technology in biomedical applications, offering precise, minimally invasive solutions for clinical procedures. Magnetic soft robots, often constructed by using magnetic particles embedded in flexible polymers, exhibit enhanced deformability and maneuverability, particularly at micro and nanoscale levels. This paper provides a comprehensive overview of the design, fabrication, and medical applications of these robots, focusing on the synthesis of magnetic materials, structural configurations, and actuation mechanisms. Structural designs are summarized, from simple one-dimensional forms to complex, multi-dimensional structures inspired by origami and kirigami principles. Additionally, magnetic actuation systems, including permanent magnets and electromagnetic coils, are examined for their respective roles in achieving the required precision or field strength for medical use. The potential applications in medicine are vast, ranging from targeted drug delivery and minimally invasive surgeries to disease diagnosis and treatment, with specific examples in tumor targeting, Alzheimer's therapy, and endodontics. The paper also addresses emerging applications in assisted reproduction and microbiota regulation. Despite challenges related to power supply, real-time tracking, and material safety, the review highlights the significant potential of magnetic soft robots to revolutionize healthcare practices.
基金supported by the National Natural Science Fundation of China(6117507411272205)
文摘This paper presents a gain-scheduling model predictive control(MPC) for linear parameter varying(LPV) systems subject to actuator saturation. The proposed gain-scheduling MPC algorithm is then applied to the lateral control of unmanned airship.The unmanned airship is modeled by an LPV-type system and transformed into a polytopic uncertain description with actuator saturation. By introducing a parameter-dependent state feedback law, the set invariance condition of the polytopic uncertain system is identified. Based on the invariant set, the gain-scheduling MPC controller is presented by solving a linear matrix inequality(LMI) optimization problem. The proposed gain-scheduling MPC algorithm is demonstrated by simulating on the unmanned airship system.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.62273297,62103353,61825304,and 6182500417in part by the Innovative Research Groups of the Natural Science Foundation of Hebei Province under Grant No.E2020203174+2 种基金in part by Hebei Innovation Capability Improvement Plan Project under Grant No.22567619Hin part by Youth Top Talent Project of Hebei Province under Grant No.HY2024050021in part by Post-graduate Innovation Fund Project of Hebei Province under Grant No.CXZZSS2023042。
文摘This paper focuses on the trajectory tracking control problem of unmanned underwater vehicles(UUVs)with unknown dead-zone inputs.The primary objective is to design an adaptive trajectory tracking error constraint controller using the fully actuated systems(FAs)approach to enable UUVs to asymptotically track target signals.Firstly,a novel error constraint fully actuated systems(ECFAs)approach is proposed by incorporating the tracking error dependent normalized function and barrier function along with time-varying scaling.Secondly,in order to deal with the model uncertainties of the UUVs,adaptive radial basis function neural networks(RBFNNs)is combined with the ECFAs approach.Then,a positive time-varying integral function is introduced to completely eliminate the effect of the residual effect caused by unknown dead-zone inputs,and it is proved that the trajectory tracking error converges to zero asymptotically based on the Lyapunov functions.Finally,the simulation results demonstrate the effectiveness of the designed adaptive controller.
基金supported by the National Defense Basic Scientific Research Program of China (Grant No.JCKY2021204B051).
文摘In this paper,a fully actuated system approach(FASA)-based control scheme is proposed for the trajectory tracking of a quadrotor unmanned aerial vehicle(UAV).System uncertainty,external disturbance and actuator constraint are all considered,which make the problem challenging.Inspired by the active disturbance rejection control(ADRC),tracking di®erentiator(TD)and extended state observer(ESO)are introduced for handling the uncertainties and generating the feedback signals.With the proposed feedback control law,the performance of the resulted closed loop system is related to its eigenstructure-eigenvalue and eigenvectors.Based on a type of control parametrization method,the parametrized eigenstructure of the closed loop system are optimized.A better performance is observed by comparative numerical simulation.
