This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state...This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state-space model by variable elimination.Considering the uncertainties from external disturbance,unknown motion information,and uncertain inertia properties,an extended state observer(ESO)is designed to estimate the total disturbance.Then,a tracking controller based on FAS approach is designed,and this makes the closed-loop system a constant linear one with an arbitrarily assignable eigenstructure.The solution to the parameter matrices of the observer and controller is given subsequently.It is proved via the Lyapunov stability theory that the observer errors and tracking errors both converge into the neighborhood of the origin.Finally,numerical simulation demonstrates the effectiveness of the proposed controller.展开更多
Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlin...Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlinear robust control law synthesized by the backstepping method.The EDOB is designed to estimate not only the influence of disturbances but also the parameter uncertainties.With the use of parameter and disturbance estimates,the nonlinear cascade controller,which consists of an outer position tracking loop and an inner load pressure loop,is further designed to attenuate the effects of parameter and disturbance estimation errors.The stability of the closed-loop system is proven by means of Lyapunov theory.Extensive comparative experimental results obtained verify the effectiveness of the proposed nonlinear cascade controller and its performance robustness to parameter and external disturbance variations in practical implementation.展开更多
基于网络控制技术的液压控制系统具有远程控制、模块化、资源共享等优点。然而,液压控制系统本身具有强非线性和参数不确定性等特点,结合网络控制系统具有的通信带宽受限等问题,导致控制效果不好而限制了应用。针对以上问题,提出一种具...基于网络控制技术的液压控制系统具有远程控制、模块化、资源共享等优点。然而,液压控制系统本身具有强非线性和参数不确定性等特点,结合网络控制系统具有的通信带宽受限等问题,导致控制效果不好而限制了应用。针对以上问题,提出一种具有事件触发机制和扩展状态观测器(Extended state observer, ESO)的自适应鲁棒控制策略。通过引入事件触发机制过滤大量的冗余数据,提高通信带宽的利用率。基于模型设计出一种扩展状态观测器,同时对速度值和不匹配外干扰进行估计。通过自适应算法在线估计液压控制系统的不确定参数。通过Lyapunov稳定性理论分析闭环系统的全局稳定性。试验表明所设计的算法在减少了大量数据传输量的同时,具有良好的位置跟踪控制性能。展开更多
基金This research was partially supported by the Science Center Program of the National Natural Science Foundation of China under Grant No.62188101the Major Program of the National Natural Science Foundation of China under Grant Nos.61690210 and 61690212the National Natural Science Foundation of China under Grant Nos.62103164 and 61703437.
文摘This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state-space model by variable elimination.Considering the uncertainties from external disturbance,unknown motion information,and uncertain inertia properties,an extended state observer(ESO)is designed to estimate the total disturbance.Then,a tracking controller based on FAS approach is designed,and this makes the closed-loop system a constant linear one with an arbitrarily assignable eigenstructure.The solution to the parameter matrices of the observer and controller is given subsequently.It is proved via the Lyapunov stability theory that the observer errors and tracking errors both converge into the neighborhood of the origin.Finally,numerical simulation demonstrates the effectiveness of the proposed controller.
基金Project(51505474)supported by the National Natural Science Foundation of ChinaProject(2015XKMS020)supported by the Fundamental Research Funds for the Central Universities,China+1 种基金Project(2016T90520)supported by the China Postdoctoral Science FoundationProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlinear robust control law synthesized by the backstepping method.The EDOB is designed to estimate not only the influence of disturbances but also the parameter uncertainties.With the use of parameter and disturbance estimates,the nonlinear cascade controller,which consists of an outer position tracking loop and an inner load pressure loop,is further designed to attenuate the effects of parameter and disturbance estimation errors.The stability of the closed-loop system is proven by means of Lyapunov theory.Extensive comparative experimental results obtained verify the effectiveness of the proposed nonlinear cascade controller and its performance robustness to parameter and external disturbance variations in practical implementation.
文摘基于网络控制技术的液压控制系统具有远程控制、模块化、资源共享等优点。然而,液压控制系统本身具有强非线性和参数不确定性等特点,结合网络控制系统具有的通信带宽受限等问题,导致控制效果不好而限制了应用。针对以上问题,提出一种具有事件触发机制和扩展状态观测器(Extended state observer, ESO)的自适应鲁棒控制策略。通过引入事件触发机制过滤大量的冗余数据,提高通信带宽的利用率。基于模型设计出一种扩展状态观测器,同时对速度值和不匹配外干扰进行估计。通过自适应算法在线估计液压控制系统的不确定参数。通过Lyapunov稳定性理论分析闭环系统的全局稳定性。试验表明所设计的算法在减少了大量数据传输量的同时,具有良好的位置跟踪控制性能。
