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Delay-dependent asymptotic stabilitzation for uncertain time-delay systems with saturating actuators

Pin-Lin Liu (2005)

International Journal of Applied Mathematics and Computer Science

This paper concerns the issue of robust asymptotic stabilization for uncertain time-delay systems with saturating actuators. Delay-dependent criteria for robust stabilization via linear memoryless state feedback have been obtained. The resulting upper bound on the delay time is given in terms of the solution to a Riccati equation subject to model transformation. Finally, examples are presented to show the effectiveness of our result.

Delay-dependent robust stability conditions and decay estimates for systems with input delays

Kostas Hrissagis, Olga I. Kosmidou (1998)

Kybernetika

The robust stabilization of uncertain systems with delays in the manipulated variables is considered in this paper. Sufficient conditions are derived that guarantee closed-loop stability under state-feedback control in the presence of nonlinear and/or time-varying perturbations. The stability conditions are given in terms of scalar inequalities and do not require the solution of Lyapunov or Riccati equations. Instead, induced norms and matrix measures are used to yield some easy to test robust stability...

Discretization schemes for Lyapunov-Krasovskii functionals in time-delay systems

Keqin Gu (2001)

Kybernetika

This article gives an overview of discretized Lyapunov functional methods for time-delay systems. Quadratic Lyapunov–Krasovskii functionals are discretized by choosing the kernel to be piecewise linear. As a result, the stability conditions may be written in the form of linear matrix inequalities. Conservatism may be reduced by choosing a finer mesh. Simplification techniques, including elimination of variables and using integral inequalities are also discussed. Systems with multiple delays and...

Extension principle and controller design for systems with distributed time-delay

Altuğ İftar (2017)

Kybernetika

Extension principle is defined for systems with distributed time-delay and the necessary and sufficient conditions for one system being an extension of the other are presented. Preservation of stability properties between two systems, one of which is an extension of the other is also discussed and it is shown that when the expanded system is an extension of the original system, (i) the original system is bounded-input bounded-output stable if and only if the expanded system is bounded-input bounded-output...

Fault tolerant control for uncertain time-delay systems based on sliding mode control

Jun Sheng Wu, Zhengxin Weng, Zuo Hua Tian, Song Jiao Shi (2008)

Kybernetika

Fault tolerant control for uncertain systems with time varying state-delay is studied in this paper. Based on sliding mode controller design, a fault tolerant control method is proposed. By means of the feasibility of some linear matrix inequalities (LMIs), delay dependent sufficient condition is derived for the existence of a linear sliding surface which guarantees quadratic stability of the reduced-order equivalent system restricted to the sliding surface. A reaching motion controller, which can...

Infinite-dimensional LMI approach to analysis and synthesis for linear time-delay systems

Kojiro Ikeda, Takehito Azuma, Kenko Uchida (2001)

Kybernetika

This paper considers an analysis and synthesis problem of controllers for linear time-delay systems in the form of delay-dependent memory state feedback, and develops an Linear Matrix Inequality (LMI) approach. First, we present an existence condition and an explicit formula of controllers, which guarantee a prescribed level of L 2 gain of closed loop systems, in terms of infinite-dimensional LMIs. This result is rather general in the sense that it covers, as special cases, some known results for...

Integral control of infinite-dimensional systems in the presence of hysteresis: an input-output approach

Hartmut Logemann, Eugene P. Ryan, Ilya Shvartsman (2007)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with integral control of systems with hysteresis. Using an input-output approach, it is shown that application of integral control to the series interconnection of either (a) a hysteretic input nonlinearity, an L2-stable, time-invariant linear system and a non-decreasing globally Lipschitz static output nonlinearity, or (b) an L2-stable, time-invariant linear system and a hysteretic output nonlinearity, guarantees, under certain assumptions, tracking of constant reference...

Invariant factors assignment for a class of time-delay systems

Jean-Jacques Loiseau (2001)

Kybernetika

It is well–known that every system with commensurable delays can be assigned a finite spectrum by feedback, provided that it is spectrally controllable. In general, the feedback involves distributed delays, and it is defined in terms of a Volterra equation. In the case of multivariable time–delay systems, one would be interested in assigning not only the location of the poles of the closed–loop system, but also their multiplicities, or, equivalently, the invariant factors of the closed–loop system....

Linear repetitive process control theory applied to a physical example

Krzysztof Gałkowski, Eric Rogers, Wojciech Paszke, David Owens (2003)

International Journal of Applied Mathematics and Computer Science

In the case of linear dynamics, repetitive processes are a distinct class of 2D linear systems with uses in areas ranging from long-wall coal cutting and metal rolling operations to iterative learning control schemes. The main feature which makes them distinct from other classes of 2D linear systems is that information propagation in one of the two independent directions only occurs over a finite duration. This, in turn, means that a distinct systems theory must be developed for them for onward...

Local asymptotic stability for nonlinear state feedback delay systems

Alfredo Germani, Costanzo Manes, Pierdomenico Pepe (2000)

Kybernetika

This paper considers the problem of output control of nonlinear delay systems by means of state delayed feedback. In previous papers, through the use of a suitable formalism, standard output control problems, such as output regulation, trajectory tracking, disturbance decoupling and model matching, have been solved for a class of nonlinear delay systems. However, in general an output control scheme does not guarantee internal stability of the system. Some results on this issue are presented in this...

Neutral functional integrodifferential control systems in Banach spaces

Krishnan Balachandran, E. Radhakrishnan Anandhi (2003)

Kybernetika

Sufficient conditions for controllability of neutral functional integrodifferential systems in Banach spaces with initial condition in the phase space are established. The results are obtained by using the Schauder fixed point theorem. An example is provided to illustrate the theory.

New qualitative methods for stability of delay systems

Erik I. Verriest (2001)

Kybernetika

A qualitative method is explored for analyzing the stability of systems. The approach is a generalization of the celebrated Lyapunov method. Whereas classically, the Lyapunov method is based on the simple comparison theorem, deriving suitable candidate Lyapunov functions remains mostly an art. As a result, in the realm of delay equations, such Lyapunov methods can be quite conservative. The generalization is here in using the comparison theorem directly with a different scalar equation with known...

New trends in design of observers for time-delay systems

Olivier Sename (2001)

Kybernetika

This paper presents some recent results about the design of observers for time-delay systems. It is focused on methods that can lead to design some useful observers in practical situations. First the links between observability properties and observers design is emphasized. Then some necessary and sufficient conditions and a method are provided to obtain unknown input observers for time-delay systems. Furthermore some H design using Lyapunov–Krasovskii and Lyapunov–Razumikhin theories are presented...

Nonlinear bounded control for time-delay systems

Germain Garcia, Sophie Tarbouriech (2001)

Kybernetika

A method to derive a nonlinear bounded state feedback controller for a linear continuous-time system with time-delay in the state is proposed. The controllers are based on an e -parameterized family of algebraic Riccati equations or on an e -parameterized family of LMI optimization problems. Hence, nested ellipsoidal neighborhoods of the origin are determined. Thus, from the Lyapunov–Krasovskii theorem, the uniform asymptotic stability of the closed-loop system is guaranteed and a certain performance...

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