Fault Diagnosis and Fault Tolerant Control Against Simultaneous Sensor and Actuator Faults for Linear Stochastic Systems

A challenging problem on observer-based, integrated fault diagnosis and fault-tolerant control for linear systems subject to actuator faults and control input constraints is studied in this paper. An adaptive observer approach is used for the joint state-fault magnitude estimation, and a feedback controller is designed to stabilize the closed-loop system without violating the actuator limits in the presence of actuator faults. Matrix inequality conditions are provided for computation of design parameters of the observer and the feedback controller, and the admissible initial conditions and estimation errors are bounded by invariant ellipsoidal sets. The design results are closely related to the fault magnitude and variation rate, and a necessary condition on the admissible fault magnitudes dependent on the control limits is directly obtained from the design process. The proposed design framework allows a direct application of the pole placement method to obtain stabilization results. To improve the system performance, a nonlinear programming-based optimization algorithm is proposed to compute an optimized feedback gain, whereas the one obtained by pole placement can be taken as an initial feasible solution for nonlinear optimization. Numerical studies with two flight control systems demonstrate the effectiveness of proposed design techniques.

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Active Fault-Tolerant Control of a Quadcopter against Time-Varying Actuator Faults and Saturations Using Sliding Mode Backstepping Approach

Applied Sciences ◽

10.3390/app9194010 ◽

2019 ◽

Vol 9 (19) ◽

pp. 4010 ◽

Cited By ~ 2

Author(s):

Ngoc Phi Nguyen ◽

Sung Kyung Hong

Keyword(s):

Fault Diagnosis ◽

Active Fault ◽

Fault Tolerant ◽

Sliding Mode ◽

Fault Tolerant Control ◽

Lyapunov Theory ◽

Fault Estimation ◽

Time Varying ◽

Actuator Faults ◽

Active Fault Tolerant Control

Fault-tolerant control is becoming an interesting topic because of its reliability and safety. This paper reports an active fault-tolerant control method for a quadcopter unmanned aerial vehicle (UAV) to handle actuator faults, disturbances, and input constraints. A robust fault diagnosis based on the H ∞ scheme was designed to estimate the magnitude of a time-varying fault in the presence of disturbances with unknown upper bounds. Once the fault estimation was complete, a fault-tolerant control scheme was proposed for the attitude system, using adaptive sliding mode backstepping control to accommodate the actuator faults, despite actuator saturation limitation and disturbances. The Lyapunov theory was applied to prove the robustness and stability of the closed-loop system under faulty operation. Simulation results show the effectiveness of the fault diagnosis scheme and proposed controller for handling actuator faults.

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Cloud-Based Fault Tolerant Control for a DC Motor System

Journal of Control Science and Engineering ◽

10.1155/2017/5670849 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Xiao He ◽

Yamei Ju ◽

Yang Liu ◽

Bangcheng Zhang

Keyword(s):

Fault Diagnosis ◽

Motor System ◽

Control Method ◽

Fault Tolerant ◽

Fault Tolerant Control ◽

Dc Motor ◽

Fault Estimation ◽

Packet Dropout ◽

Actuator Faults ◽

The Stability

The fault tolerant control problem for a DC motor system is investigated in a cloud environment. Packet dropout phenomenon introduced by the limited-capacity communication channel is considered. Actuator faults are taken into consideration and fault diagnosis and fault tolerant control methods towards actuator faults are proposed to enhance the reliability of the whole cloud-based DC motor system. The fault diagnosis unit is then established with purpose of obtaining fault information. When the actuator fault is detected by comparing the residual signal with a predefined threshold, a residual matching approach is utilized to locate the fault. The fault can be further estimated by a least-squares filter. Based on the fault estimation, a fault tolerant controller is designed to guarantee the stability as well as the control performance of the DC motor system. Simulation result on a DC motor system shows the efficiency of the fault tolerant control method proposed in this paper.

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Fault diagnosis and fuzzy fault-tolerant control design of nonlinear systems with actuator faults

2016 35th Chinese Control Conference (CCC) ◽

10.1109/chicc.2016.7554381 ◽

2016 ◽

Cited By ~ 1

Author(s):

Yongming Li ◽

Shaocheng Tong

Keyword(s):

Fault Diagnosis ◽

Nonlinear Systems ◽

Fault Tolerant ◽

Control Design ◽

Fault Tolerant Control ◽

Actuator Faults

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Fault Diagnosis and Fault-Tolerant Control Scheme for Quadcopter UAVs with a Total Loss of Actuator

Energies ◽

10.3390/en12061139 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1139 ◽

Cited By ~ 7

Author(s):

Ngoc Nguyen ◽

Sung Hong

Keyword(s):

Fault Diagnosis ◽

Active Fault ◽

Control Method ◽

Fault Tolerant ◽

Sliding Mode ◽

Fault Tolerant Control ◽

Total Loss ◽

Actuator Faults ◽

Control Scheme ◽

Robust Adaptive

Fault-tolerant control has drawn attention in recent years owning to its reliability and safe flight during missions. In this article, an active fault-tolerant control method is proposed to control a quadcopter in the presence of actuator faults and disturbances. Firstly, the dynamics of the quadcopter are presented. Secondly, a robust adaptive sliding mode Thau observer is presented to estimate the time-varying magnitudes of actuator faults. Thirdly, a fault-tolerant control scheme based on sliding mode control and reconfiguration technique is designed to maintain the quadcopter at the desired position despite the presence of faults. Unlike previous studies, the proposed method aims to integrate the fault diagnosis and a fault-tolerant control scheme into a single unit with total loss of actuator. Simulation results illustrate the efficiency of the suggested algorithm.

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