In this paper, a new nonlinear augmented observer is proposed and applied to satellite attitude control systems. The observer can estimate system state and actuator fault simultaneously. It can enhance the performance...In this paper, a new nonlinear augmented observer is proposed and applied to satellite attitude control systems. The observer can estimate system state and actuator fault simultaneously. It can enhance the performances of rapidly-varying faults estimation. Only original system matrices are adopted in the parameter design. The considered faults can be unbounded, and the proposed augmented observer can estimate a large class of faults. Systems without disturbances and the fault whose finite times derivatives are zero piecewise are initially considered, followed by a discussion of a general situation where the system is subject to disturbances and the finite times derivatives of the faults are not null but bounded. For the considered nonlinear system, convergence conditions of the observer are provided and the stability analysis is performed using Lyapunov direct method. Then a feasible algorithm is explored to compute the observer parameters using linear matrix inequalities （LMIs）. Finally, the effectiveness of the proposed approach is illustrated by considering an example of a closed-loop satellite attitude control system. The mance in estimating states and actuator faults. It also successfully. simulation results show satisfactory perfor- shows that multiple faults can be estimated展开更多
针对具有参数不确定和延迟环节的马尔科夫跳变系统,在状态转移概率矩阵(Transition probability matrix,TPM)不确定的情形下,讨论了其执行器和传感器故障同时估计的方法.通过扩展系统状态,将系统转换为一个具有马尔科夫跳变参数的广义...针对具有参数不确定和延迟环节的马尔科夫跳变系统,在状态转移概率矩阵(Transition probability matrix,TPM)不确定的情形下,讨论了其执行器和传感器故障同时估计的方法.通过扩展系统状态,将系统转换为一个具有马尔科夫跳变参数的广义描述系统,基于此广义描述系统设计马尔科夫跳变观测器实现对其状态和传感器故障的估计.与此同时,还设计了一组自适应律对执行器故障进行在线调节.通过求解一组线性矩阵不等式最优化问题,得到观测器存在的充分条件.最后,针对两个数值实例,验证了所设计方法的有效性.展开更多
An active fault tolerant control scheme is investigated for the attitude control systems of spacecraft with external disturbance and actuator faults by using the sliding mode technique. Firstly,the dynamic equations a...An active fault tolerant control scheme is investigated for the attitude control systems of spacecraft with external disturbance and actuator faults by using the sliding mode technique. Firstly,the dynamic equations and kinematic equations of spacecraft are given. For the dynamic mode of spacecraft in faulty case,a fault diagnosis component is used for fault detection and estimation by using a nonlinear observer. According to the fault estimation information obtained during the fault diagnosis,the fault tolerant control scheme is developed by adopting the backstepping sliding mode control technique. Meanwhile,the Lyapunov theory is used to analyze the stability of the closed-loop attitude systems. Finally,simulation results for the attitude dynamics models show the feasibility of the proposed fault tolerant scheme.展开更多
基金supported by the National Basic Research Program of China(No.2012CB720003)the National Natural Science Foundation of China(No.61203151)
文摘In this paper, a new nonlinear augmented observer is proposed and applied to satellite attitude control systems. The observer can estimate system state and actuator fault simultaneously. It can enhance the performances of rapidly-varying faults estimation. Only original system matrices are adopted in the parameter design. The considered faults can be unbounded, and the proposed augmented observer can estimate a large class of faults. Systems without disturbances and the fault whose finite times derivatives are zero piecewise are initially considered, followed by a discussion of a general situation where the system is subject to disturbances and the finite times derivatives of the faults are not null but bounded. For the considered nonlinear system, convergence conditions of the observer are provided and the stability analysis is performed using Lyapunov direct method. Then a feasible algorithm is explored to compute the observer parameters using linear matrix inequalities （LMIs）. Finally, the effectiveness of the proposed approach is illustrated by considering an example of a closed-loop satellite attitude control system. The mance in estimating states and actuator faults. It also successfully. simulation results show satisfactory perfor- shows that multiple faults can be estimated
文摘针对具有参数不确定和延迟环节的马尔科夫跳变系统,在状态转移概率矩阵(Transition probability matrix,TPM)不确定的情形下,讨论了其执行器和传感器故障同时估计的方法.通过扩展系统状态,将系统转换为一个具有马尔科夫跳变参数的广义描述系统,基于此广义描述系统设计马尔科夫跳变观测器实现对其状态和传感器故障的估计.与此同时,还设计了一组自适应律对执行器故障进行在线调节.通过求解一组线性矩阵不等式最优化问题,得到观测器存在的充分条件.最后,针对两个数值实例,验证了所设计方法的有效性.
基金partially supported by the National Natural Science Foundation of China(No. 61473143)Postgraduate Research & Practice Innovation Program of Jiangsu Province(No. KYCX18_0299)the China Scholarships Council(No. 201806830102)
文摘An active fault tolerant control scheme is investigated for the attitude control systems of spacecraft with external disturbance and actuator faults by using the sliding mode technique. Firstly,the dynamic equations and kinematic equations of spacecraft are given. For the dynamic mode of spacecraft in faulty case,a fault diagnosis component is used for fault detection and estimation by using a nonlinear observer. According to the fault estimation information obtained during the fault diagnosis,the fault tolerant control scheme is developed by adopting the backstepping sliding mode control technique. Meanwhile,the Lyapunov theory is used to analyze the stability of the closed-loop attitude systems. Finally,simulation results for the attitude dynamics models show the feasibility of the proposed fault tolerant scheme.
