In this paper,a new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning is presented in this paper.The existence of nonlinear terms in the studied sy...In this paper,a new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning is presented in this paper.The existence of nonlinear terms in the studied system makes it very difficult to design the optimal controller using traditional methods.To achieve optimal control,RL algorithm based on critic–actor architecture is considered for the nonlinear system.Due to the significant security risks of network transmission,the system is vulnerable to deception attacks,which can make all the system state unavailable.By using the attacked states to design coordinate transformation,the harm brought by unknown deception attacks has been overcome.The presented control strategy can ensure that all signals in the closed-loop system are semi-globally ultimately bounded.Finally,the simulation experiment is shown to prove the effectiveness of the strategy.展开更多
磁悬浮系统能使铁磁性物体悬浮在空中,可以应用于科研、医疗、娱乐、交通等多个领域。为了解决非线性、不稳定磁悬浮系统的控制问题,建立了磁悬浮时滞系统的数学模型,采用了Backstepping控制以及RBF神经网络和Backstepping控制结合的方...磁悬浮系统能使铁磁性物体悬浮在空中,可以应用于科研、医疗、娱乐、交通等多个领域。为了解决非线性、不稳定磁悬浮系统的控制问题,建立了磁悬浮时滞系统的数学模型,采用了Backstepping控制以及RBF神经网络和Backstepping控制结合的方法进行研究,采用李雅普诺夫稳定性理论分别设计非线性控制器,保证闭环系统的理论稳定。在此基础上,利用Radial basis function (RBF)神经网络的逼近特性,设计了自适应律,研究了对系统中未知函数的拟合。最后,通过MATLAB对两种控制方法的效果进行对比,仿真结果表明,两种方法均能使系统稳定,RBF神经网络与Backstepping控制结合的方法能较快实现稳定,效果更好,且RBF神经网络对未知函数的拟合效果也良好。展开更多
Hydraulic servo system plays an important role in industrial fields due to the advantages of high response,small size-to-power ratio and large driving force.However,inherent nonlinear behaviors and modeling uncertaint...Hydraulic servo system plays an important role in industrial fields due to the advantages of high response,small size-to-power ratio and large driving force.However,inherent nonlinear behaviors and modeling uncertainties are the main obstacles for hydraulic servo system to achieve high tracking perfor-mance.To deal with these difficulties,this paper presents a backstepping sliding mode controller to improve the dynamic tracking performance and anti-interfer-ence ability.For this purpose,the nonlinear dynamic model is firstly established,where the nonlinear behaviors and modeling uncertainties are lumped as one term.Then,the extended state observer is introduced to estimate the lumped distur-bance.The system stability is proved by using the Lyapunov stability theorem.Finally,comparative simulation and experimental are conducted on a hydraulic servo system platform to verify the efficiency of the proposed control scheme.展开更多
In this paper, an actuator fault diagnosis scheme based on the backstepping method is proposed for a class of nonlinear heat equations. The fault diagnosis scheme includes fault detection, fault estimation and time to...In this paper, an actuator fault diagnosis scheme based on the backstepping method is proposed for a class of nonlinear heat equations. The fault diagnosis scheme includes fault detection, fault estimation and time to failure (TTF) prediction. Firstly, we achieve fault detection by comparing the detection residual with a predetermined threshold, where the detection residual is defined as the difference between the observer output and the system measurement output. Then, we estimate the fault function through the fault parameter update law and calculate the TTF using only limited measurements. Finally, the numerical simulation is performed on a nonlinear heat equation to verify the effectiveness of the proposed fault diagnosis scheme.展开更多
基金supported in part by the National Key R&D Program of China under Grants 2021YFE0206100in part by the National Natural Science Foundation of China under Grant 62073321+2 种基金in part by National Defense Basic Scientific Research Program JCKY2019203C029in part by the Science and Technology Development Fund,Macao SAR under Grants FDCT-22-009-MISE,0060/2021/A2 and 0015/2020/AMJin part by the financial support from the National Defense Basic Scientific Research Project(JCKY2020130C025).
文摘In this paper,a new optimal adaptive backstepping control approach for nonlinear systems under deception attacks via reinforcement learning is presented in this paper.The existence of nonlinear terms in the studied system makes it very difficult to design the optimal controller using traditional methods.To achieve optimal control,RL algorithm based on critic–actor architecture is considered for the nonlinear system.Due to the significant security risks of network transmission,the system is vulnerable to deception attacks,which can make all the system state unavailable.By using the attacked states to design coordinate transformation,the harm brought by unknown deception attacks has been overcome.The presented control strategy can ensure that all signals in the closed-loop system are semi-globally ultimately bounded.Finally,the simulation experiment is shown to prove the effectiveness of the strategy.
文摘磁悬浮系统能使铁磁性物体悬浮在空中,可以应用于科研、医疗、娱乐、交通等多个领域。为了解决非线性、不稳定磁悬浮系统的控制问题,建立了磁悬浮时滞系统的数学模型,采用了Backstepping控制以及RBF神经网络和Backstepping控制结合的方法进行研究,采用李雅普诺夫稳定性理论分别设计非线性控制器,保证闭环系统的理论稳定。在此基础上,利用Radial basis function (RBF)神经网络的逼近特性,设计了自适应律,研究了对系统中未知函数的拟合。最后,通过MATLAB对两种控制方法的效果进行对比,仿真结果表明,两种方法均能使系统稳定,RBF神经网络与Backstepping控制结合的方法能较快实现稳定,效果更好,且RBF神经网络对未知函数的拟合效果也良好。
基金Thework issupportedby the Key Scienceand Technology Programof Henan Province(Grant No.222102220104)the Science and Technology Key Project Foundation of Henan Provincial Education Department(Grant No.23A460014)the High Level Talent Foundation of Henan University of Technology(Grant No.2020BS043).
文摘Hydraulic servo system plays an important role in industrial fields due to the advantages of high response,small size-to-power ratio and large driving force.However,inherent nonlinear behaviors and modeling uncertainties are the main obstacles for hydraulic servo system to achieve high tracking perfor-mance.To deal with these difficulties,this paper presents a backstepping sliding mode controller to improve the dynamic tracking performance and anti-interfer-ence ability.For this purpose,the nonlinear dynamic model is firstly established,where the nonlinear behaviors and modeling uncertainties are lumped as one term.Then,the extended state observer is introduced to estimate the lumped distur-bance.The system stability is proved by using the Lyapunov stability theorem.Finally,comparative simulation and experimental are conducted on a hydraulic servo system platform to verify the efficiency of the proposed control scheme.
文摘In this paper, an actuator fault diagnosis scheme based on the backstepping method is proposed for a class of nonlinear heat equations. The fault diagnosis scheme includes fault detection, fault estimation and time to failure (TTF) prediction. Firstly, we achieve fault detection by comparing the detection residual with a predetermined threshold, where the detection residual is defined as the difference between the observer output and the system measurement output. Then, we estimate the fault function through the fault parameter update law and calculate the TTF using only limited measurements. Finally, the numerical simulation is performed on a nonlinear heat equation to verify the effectiveness of the proposed fault diagnosis scheme.
