Fault-tolerant sampled-data control of flexible spacecraft with probabilistic time delays

Abstract

In this paper, fault-tolerant sampled-data control for flexible spacecraft in the presence of external disturbances, partial actuator failures and probabilistic time delays is investigated. In particular, unlike the common assumptions on continuous-time information on control input, a more realistic sampled-data communication strategy is proposed with probabilistic occurrence of time-varying delays which is modeled by introducing Bernoulli distributed sequences. The main purpose of this paper is to derive fault-tolerant sampled-data control law which makes the closed-loop system robustly asymptotically stable with a prescribed upper bound of the cost function about its equilibrium point for all possible actuator failures. More precisely, by constructing an appropriate Lyapunov-Krasovskii functional involving the lower and upper bound of the probabilistic time delay, a new set of sufficient conditions are derived in terms of linear matrix inequalities for achieving the required result. Numerical simulations are presented by taking the real parameters to the considered aircraft model, which is not only highlighting the ensured closed-loop performance by the proposed control law, but also illustrates its superior fault tolerance, fast convergence and robustness in the presence of external disturbances and actuator faults when compared with the conventional controller. The simulation result reveals the effectiveness and potential of the proposed new design techniques.

Robust reliable L2 – L∞ control for continuous‐time systems with nonlinear actuator failures

“…Therefore, in the view point of practical applications, it is necessary to consider the reliable control strategy with the nonlinear actuator faults. Moreover, during past two decades, the development of digital technology is at its peak, hence the consideration of sampled‐data control has become more important, see for instant . Inspired by the above ideals, we have considered the sampled‐data reliable control together with nonlinear actuator failures to analyze the stability of continuous‐time systems with an L 2 – L ∞ performance.…”

“…This time delay may be variable due to the complex disturbances or other conditions. At the same time, since the digital hardware and communication technologies are rapidly developing, the problem of stabilization of linear systems using delayed control input via sampled‐data control scheme has been received much attention among the research communities . In particular, the sampled‐data control problem will be formulated through an input delay approach.…”

“…On another research frontier, sampled‐data control theory has attracted much attention among the control communities because of the modern control systems usually use digital technology for controller implementation. Due to this reason, a huge number of interesting and essential results related to sampled‐data control problem has been reported in the literature (see and the references therein). Particularly, in , the authors investigated the exponential stability of the chaotic systems represented by Takagi–Sugeno fuzzy model under sampled‐data controller.…”

“…Furthermore, the robust reliable sampled‐data control problem for an offshore steel jacket platform with input time‐varying delay and actuator faults subject to nonlinear forces has been studied in . Very recently, Sakthivel et al addressed the fault‐tolerant sampled‐data control problem for flexible spacecraft in the presence of external disturbances, partial actuator failures and probabilistic time delays. Moreover, in control theory and engineering applications, the L 2 – L ∞ control has very important significance that lies in its performance index which can control the output value minimization.…”

H∞filtering for networked linear systems with multiple packet dropouts and random delays

“…But the lower bound of delay cannot be zero and the Lyapunov-Krasovskii functional candidate is complex. In recent literature [31], a new method is presented to deal with the bounded delay where the lower bound can be equal to zero. But the data packet dropouts are not considered.…”