Adaptive Fault-Tolerant Sliding Mode Control for High-Speed Trains With Actuator Faults Under Strong Winds

This paper presents a fault-tolerant control scheme for a class of nonlinear systems with actuator faults and unknown input disturbances. First, the sliding mode control law is designed based on the reaching law method. Then, in view of unpredictable state variables and unknown information in the control law, the original system is transformed into two subsystems through a coordinate transformation. One subsystem only has actuator faults, and the other subsystem has both actuator faults and disturbances. A sliding mode observer is designed for the two subsystems, respectively, and the equivalence principle of the sliding mode variable structure is used to realize the accurate reconstruction of the actuator faults and disturbances. Finally, the observation value and the reconstruction value are used to carry out an online adjustment to the designed sliding mode control law, and fault-tolerant control of the system is realized. The simulation results are presented to demonstrate the approach.

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Fault tolerant control for robotic manipulator using fractional-order backstepping fast terminal sliding mode control

Transactions of the Institute of Measurement and Control ◽

10.1177/01423312211022449 ◽

2021 ◽

pp. 014233122110224

Author(s):

Zeeshan Anjum ◽

Yu Guo ◽

Wei Yao

Keyword(s):

Sliding Mode Control ◽

Fractional Order ◽

Fault Tolerant ◽

Sliding Mode ◽

Terminal Sliding Mode Control ◽

Actuator Faults ◽

Terminal Sliding Mode ◽

Control Approach ◽

Mode Control ◽

Fast Terminal Sliding Mode

In this paper, the problems of tracking control and finite-time stabilization of a high nonlinear system such as a robotic manipulator in the presence of actuator faults, uncertainties, and external disturbances are explored. In order to improve the performance of the system in the presence of actuator faults, uncertainties and external disturbances a novel fault tolerant control system based on fractional-order backstepping fast terminal sliding mode control is developed in this paper. The control system is developed by employing the results obtained from studies in the fields of fractional-order calculus, backstepping, sliding mode control, Mittag–Leffler stability, and finite-time Lyapunov stability. The performance of the suggested controller is then tested for a PUMA560 robot in which the first three joints are used. The simulation results validate the usefulness of the developed control approach in terms of accuracy of tracking, and convergence speed in the presence of disturbances, uncertainties and actuator faults. The trajectory tracking performance of the developed method is compared with other state of the art approaches such as conventional computed torque control, proportional integral derivative control and nonsingular fast terminal sliding mode control. The simulation results show that the proposed control approach performed better as compared to other control approaches in the presence of actuator faults, uncertainties, and disturbances.

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Distributed Cooperative Sliding Mode Fault-Tolerant Control for Multiple High-Speed Trains Based on Actor-Critic Neural Network

Journal of Mathematics ◽

10.1155/2021/9943170 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Xiangyu Kong ◽

Tong Zhang

Keyword(s):

Neural Network ◽

Time Delay ◽

High Speed ◽

Fault Tolerant ◽

Sliding Mode ◽

Tracking Error ◽

Fault Tolerant Control ◽

Actuator Faults ◽

High Speed Trains ◽

Critic Neural Network

This article investigates the cooperative fault-tolerant control problem for multiple high-speed trains (MHSTs) with actuator faults and communication delays. Based on the actor-critic neural network, a distributed sliding mode fault-tolerant controller is designed for MHSTs to solve the problem of actuator faults. To eliminate the negative effects of unknown disturbances and time delay on train control system, a distributed radial basis function neural network (RBFNN) with adaptive compensation term of the error is designed to approximate the nonlinear disturbances and predict the time delay, respectively. By calculating the tracking error online, an actor-critic structure with RBFNN is used to estimate the switching gain of the distributed controller, which reduces the chattering phenomenon caused by sliding mode control. The global stability and ultimate bounded of all signals of the closed-loop system are proposed with strict mathematic proof. Simulations show that the proposed method has superior effectiveness and robustness compared with other fault-tolerant control methods, which ensures the safe operation of MHSTs under moving block conditions.

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Model-Independent Adaptive Fault-Tolerant Tracking Control for High-Speed Trains with Actuator Saturation

Applied Sciences ◽

10.3390/app9194146 ◽

2019 ◽

Vol 9 (19) ◽

pp. 4146 ◽

Cited By ~ 1

Author(s):

Chuanfang Xu ◽

Xiyou Chen ◽

Lin Wang

Keyword(s):

Tracking Control ◽

High Speed ◽

Actuator Saturation ◽

Fault Tolerant ◽

Sliding Mode ◽

Upper Bounds ◽

Model Parameters ◽

Actuator Faults ◽

High Speed Trains ◽

Model Independent

This paper investigates the fault-tolerant tracking control problem of high-speed trains (HSTs) subject to unknown model parameters with unavailable uncertainties, unmeasurable additional disturbance, and unpredictable actuator faults constrained by actuator saturation. An adaptive passive fault-tolerant tracking control strategy based on variable-gain proportion-integral-derivative (PID)-type sliding mode surface is proposed to handle the problem. Unknown model parameters, gains of the PID-type sliding mode surface, and upper bounds of the lumped system uncertainty which includes additional disturbance, modeling uncertainties, and uncertainties resulting from actuator faults, are estimated online by adaptive technology. The input saturation (actuator output saturation) constraint is handled by introducing an auxiliary signal. The proposed controller can compensate for the effects of the lumped uncertainty and the actuator faults effectively. Moreover, the controller is model-independent, which means it requires no prior knowledge of model parameters and upper bounds of the lumped uncertainty, and does not depend upon fault detection and diagnosis module. The asymptotic stability of the closed-loop train system is demonstrated by Lyapunov theory. Good fault-tolerant tracking capacity, effective anti-actuator saturation ability, and strong robustness of the proposed controller are verified via numerical simulation.

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An adaptive sliding mode actuator fault tolerant control scheme for octorotor system

International Journal of Advanced Robotic Systems ◽

10.1177/1729881419832435 ◽

2019 ◽

Vol 16 (2) ◽

pp. 172988141983243 ◽

Cited By ~ 3

Author(s):

Fatima Ejaz ◽

Mirza Tariq Hamayun ◽

Shariq Hussain ◽

Salman Ijaz ◽

Shunkun Yang ◽

...

Keyword(s):

Sliding Mode Control ◽

Fault Tolerant ◽

Sliding Mode ◽

Fault Tolerant Control ◽

Adaptive Sliding Mode Control ◽

Actuator Faults ◽

Control Approach ◽

Adaptive Sliding Mode ◽

Mode Control ◽

Control Scheme

In this article, an adaptive sliding mode control is used in the framework of fault tolerant control to mitigate the effects of actuator faults without requiring the actuator health information. Since unmanned aerial vehicles are being used in multiple fields such as military, surveillance, media, agriculture, communication and trading sector, therefore it is of vital importance to overcome the effects of actuator faults that can decline system performance and can even lead to some serious accidents. The proposed adaptive sliding mode control approach can handle actuator faults directly without requiring any faults information and adaptively adjusts controller gains to maintain acceptable level of performance. To validate the effectiveness of the proposed adaptive fault tolerant control scheme, it has been tested in simulations using non-linear Benchmark model of Octorotor system and its performance is compared with the optimal LQR control approach.

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Finite-Time Attitude Fault Tolerant Control of Quadcopter System via Neural Networks

Mathematics ◽

10.3390/math8091541 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1541 ◽

Cited By ~ 1

Author(s):

Ngoc Phi Nguyen ◽

Nguyen Xuan Mung ◽

Le Nhu Ngoc Thanh Ha ◽

Tuan Tu Huynh ◽

Sung Kyung Hong

Keyword(s):

Sliding Mode Control ◽

Fault Tolerant ◽

Sliding Mode ◽

Fault Tolerant Control ◽

Terminal Sliding Mode Control ◽

Actuator Faults ◽

Model Uncertainties ◽

Terminal Sliding Mode ◽

Mode Control ◽

Fast Terminal Sliding Mode

This study investigates the design of fault-tolerant control involving adaptive nonsingular fast terminal sliding mode control and neural networks. Unlike those of previous control strategies, the adaptive law of the investigated algorithm is considered in both continuous and discontinuous terms, which means that any disturbances, model uncertainties, and actuator faults can be simultaneously compensated for. First, a quadcopter model is presented under the conditions of disturbances and uncertainties. Second, normal adaptive nonsingular fast terminal sliding mode control is utilized to handle these disturbances. Thereafter, fault-tolerant control based on adaptive nonsingular fast terminal sliding mode control and neural network approximation is presented, which can handle the actuator faults, model uncertainties, and disturbances. For each controller design, the Lyapunov function is applied to validate the robustness of the investigated method. Finally, the effectiveness of the investigated control approach is presented via comparative numerical examples under different fault conditions and uncertainties.

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