Article
Transactions of the Institute of
Measurement and Control
2014, Vol. 36(6) 797–804
Ó The Author(s) 2014
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DOI: 10.1177/0142331214524266
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Observer-based finite-time passive control
for a class of uncertain time-delayed
Lipschitz nonlinear systems
Jun Song and Shuping He
Abstract
The observer-based finite-time passive control problem of a class of Lipschitz nonlinear systems with uncertainties and time delays is studied. The non-
linear parameters are considered to satisfy the global Lipschitz conditions and the exogenous disturbances are unknown but energy-bounded. By con-
structing an appropriate Lyapunov function, a observer-based state feedback controller is designed to guarantee that the resulting closed-loop system
is finite-time bounded and satisfies the given passive constraint condition. Some sufficient conditions for the solution to this problem are derivedin
terms of linear matrix inequalities. Simulation results illustrate the validity of the proposed approach.
Keywords
Global Lipschitz conditions, time-delayed nonlinear system, observer-based state feedback, finite-time bounded, passive control
Introduction
Over the past three decades, the nonlinear systems with nonli-
nearities which satisfy the global Lipschitz conditions have
been extensively studied by many researchers (see Chen et al.,
2011; Song and He, 2013; Zemouche and Boutayeb, 2006,
2011; Zhu and Han, 2002), and time delays are frequently
encountered in various practical systems, such as chemical
engineering systems, neural networks and population dynamic
models, etc. The study of nonlinear systems with time delays
has received much attention during the past years. To mention
a few, in Zemouche and Boutayeb (2011), the authors investi-
gated the problem of observer design for a class of time-
delayed Lipschitz nonlinear discrete-time systems; in Chiu
and Chiang (2011), the authors studied the problem of expo-
nential stabilization control for a class of uncertain nonlinear
systems with state and input delays; and in Liu et al. (2010),
the authors considered the problem of non-fragile observer-
based passive control for uncertain time-delay systems sub-
jected to input nonlinearity. But among these results, passivity
analysis and synthesis have attracted less attention. Passivity
is part of a broader and more general theory of dissipativity.
For more details on the literature related to passivity, the
readers can refer to Bao and Min (2006), Chen et al. (2010),
Liu et al. (2010), Zeng et al. (2011), and the references therein.
However, in some practical applications, the operating
time of dynamic systems is limited. Lipschitz nonlinear sys-
tems, which were mentioned in the above paragraph, belong
to these dynamic systems. Namely, the Lipschitz nonlinear
systems concerned work in a fixed finite time interval. Then,
the given control methods in the aforementioned literature
will lose their function, because the results of these papers are
mostly based on Lyapunov stable theory which pays more
attention to the asymptotic pattern of systems over an infinite
time interval (Qiu et al., 2012). To deal with such situations,
Dorato (1961) first presented the concept of finite-time stabi-
lity (or short-time stability), and Amato et al. (2001) first pro-
posed the concept of finite-time boundedness. Since then, a
lot of attempts at finite-time control problems have been
made in Amato and Ariola (2005), He and Liu (2011, 2012),
Xiang et al. (2012a,b), and so on.
To the best of our knowledge, the observer-based finite-
time control problem of a class of Lipschitz nonlinear systems
with time delay has not been fully investigated. This motivates
our research. This paper considers the observer-based finite-
time passive control problem of a class of Lipschitz nonlinear
systems with time delay and uncertainties, and the nonlinear
parameters are assumed to satisfy the global Lipschitz condi-
tions. By using the Lyapunov function approach and linear
matrix inequality (LMI) techniques, some sufficient condi-
tions for the existence of the state feedback controller and
observer are given. Then, this problem is reduced to an opti-
mization problem under the constraint of LMIs. Finally, a
simulation example illustrates the effectiveness of the devel-
oped techniques.
Notation. In the sequel, if not explicitly stated, matrices are
assumed to have compatible dimensions. I and 0 represent
School of Electrical Engineering and Automation, Anhui University, Hefei,
China
Corresponding author:
Shuping He, School of Electrical Engineering and Automation, Anhui
University, Hefei 230601, China.
Email: shuping.he@ahu.edu.cn
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