Distributed adaptive fault‐tolerant consensus tracking of multi‐agent systems against time‐varying actuator faults

In this paper, the problem of fault-tolerant insensitive control is addressed for a class of linear time-invariant continuous-time systems against bounded time-varying actuator faults and controller gain variations. Adaptive mechanisms are developed to adjust controller gains in order to compensate for the detrimental effects of partial loss of control effectiveness and bias-actuator faults. Variations of controller gains arise from time-varying and bounded perturbations that are supposed to always exist in adaptive mechanisms. Based on the disturbed outputs of adaptive mechanisms, three different adaptive control strategies are constructed to achieve bounded stability results of the closed-loop adaptive fault-tolerant control systems in the presence of actuator faults and controller gain variations. Furthermore, comparisons of convergence boundaries of states and limits of control inputs among adaptive strategies are developed in this paper. The efficiency of the proposed adaptive control strategies and their comparisons are demonstrated by a rocket fairing structural-acoustic model. KEYWORDS actuator faults, bounded stability, disturbed adaptive mechanisms, fault-tolerant control system INTRODUCTIONIn a practical control system, it is inevitable that a component such as an actuator or a sensor is faulty at some instants because of the reason of coming from the component's quality, external working environment, internal operation conditions, etc. Under unexpected faults of components, fault-tolerant control (FTC) designs are critical to be developed to maintain stability of systems and prevent performance degradation seriously. 1,2 During the past two decades, various FTC and some relative methods have been proposed for nonlinear systems such as aircraft, 3,4 robots, 5,6 interconnected systems such as networked systems 7,8 and multiagent systems, 9-11 linear systems with time delays, 12 uncertainties and disturbances, 13 state/input saturations, 14,15 and controller gain variations. 16,17 Among those methods, active FTC has received increasing attention because of its advantages of online changing controller structure and adjusting the control parameters to accommodate actuator and sensor faults.The existing active FTC designs can be broadly classified into two categories, that is, fault detection and isolation (FDI)-based FTC and adaptive FTC designs. In the study of FDI-based FTC systems, FTC strategies are designed based on the exactly faulty information, which is obtained by FDI mechanisms. 13,18 On the other hand, an adaptive technique that can estimate the changes of system parameters in real time has been widely used to deal with many issues in Int J Adapt Control Signal Process. 2019;33: 175-195. wileyonlinelibrary.com/journal/acs

Section: Comparison Results Of the Proposed Adaptive Methods And The mentioning

confidence: 99%

Section: Comparison Results Of the Proposed Adaptive Methods And The mentioning

confidence: 99%

Section: Comparison Results Of the Proposed Adaptive Methods And The mentioning

confidence: 99%

Section: Comparison Results Of the Proposed Adaptive Methods And The mentioning

confidence: 99%

Section: Comparison Results Of the Proposed Adaptive Methods And The mentioning

confidence: 99%

See 3 more Smart Citations

Comparisons of adaptive fault‐tolerant insensitive control methods for a class of linear systems

Jin

Lü

Tan

et al. 2018

Hierarchical structure‐based adaptive fault‐tolerant consensus control for multiple 3‐DOF laboratory helicopters

Jiang

Patton

et al. 2020

SummaryThis study investigates the consensus problem of multiple 3‐DOF laboratory helicopters modeled with system nonlinearity, uncertainty, and actuator faults. The simultaneous additives and partial loss of effectiveness actuator faults are considered. The fault detection hierarchy, the healthy control hierarchy, and the fault‐tolerant control hierarchy constitute the hierarchical structure of multihelicopter systems. The fault‐tolerant consensus protocol is switched from the healthy control hierarchy once the actuator fault is detected in the fault detection hierarchy. An adaptive fault‐tolerant consensus control scheme is developed on the basis of the instantaneous and integral estimations to compensate simultaneously for system nonlinearity, uncertainty, and actuator faults and to guarantee the mean‐square consensus in a completely distributed form. Simulation results are presented to validate the effectiveness of the proposed adaptive fault‐tolerant consensus control algorithm.

Energy efficient nonfragile control protocol for nonlinear large‐scale systems with input quantization

Tharanidharan

Sakthivel

Ren

et al. 2020

SummaryThe problem of robust stabilization for a class of nonlinear large‐scale systems with the energy constraints and time‐varying actuator faults is addressed in this article. In the considered system, the stabilization criteria is achieved via a sensor‐network‐based distributed fault‐tolerant controller. Moreover to limit the consumption of energy by the sensors, the measurement size reduction technique and communication rate reduction approach are implemented such that the resulting closed‐loop system is stable within a predefined extended passive performance index level. In particular, the sensor signal quantization technique is used to reduce the frequency and size of the transmitted data packet in the communication sequence. Based on the switched system theory and Lyapunov approach, a new set of sufficient conditions is obtained in the form of linear matrix inequality constraints to ensure the exponential stabilization of the considered system. The developed fault‐tolerant resilient control gains are designed by resorting to the cone complementarity linearization algorithm. Moreover, a nonisothermal continuous stirred‐tank reactor with interconnection is considered as an example to demonstrate the effectiveness of the proposed design technique.