A non-fragile robust observer design for uncertain time-delay fractional Ito stochastic systems with input nonlinearity: An SMC approach


Khandani K., Parvizian M., EFE M. Ö.

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART I-JOURNAL OF SYSTEMS AND CONTROL ENGINEERING, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume:
  • Publication Date: 2021
  • Doi Number: 10.1177/09596518211040008
  • Title of Journal : PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART I-JOURNAL OF SYSTEMS AND CONTROL ENGINEERING
  • Keywords: Non-fragile observer, fractional Ito stochastic systems, sliding mode control, linear matrix inequalities, input nonlinearity, SLIDING MODE CONTROL, BROWNIAN-MOTION, EQUATIONS, DRIVEN, STABILIZATION

Abstract

This article considers the problem of non-fragile observer design for uncertain fractional Ito stochastic systems. The design is based on a sliding surface whose reachability in finite time is guaranteed by introducing a novel sliding mode control law. Employing the fractional infinitesimal operator and the related lemmas, the stochastic stability of the overall closed-loop system is transformed to the problem of solving a set of linear matrix inequalities. Addressing the fragility issue, a norm-bounded term is added to the observer gain, which prevents failure of the estimation error system. The adverse effects of the input nonlinearity and time-varying delay are alleviated by the proposed approach. Furthermore, the present method is investigated for the fractional Ito stochastic systems with known states. A numerical example is presented to illustrate the effectiveness of the proposed method.