الفهرس 
chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
The periodic signal tracking and the unknown disturbance rejection under limited
communication resources are main important issues in many physical systems
and practical applications. The control of such systems has some challenges such
as nonlinearity, time-varying delay, unknown external disturbances, structure
uncertainty, and the heavy communication burden on the sensors and controller.
These challenges affect the system performance and may destabilize the system.
Hence, in this thesis, three schemes have been designed to overcome these
challenges to achieve a good control performance and to guarantee the closedloop system stability.
The proposed schemes can be described as: the modified repetitive control
(MRC) with periodic event-triggered feedback observer (PETFO) based on
equivalent-input-disturbance (EID) estimator, MRC with fuzzy PETFO
(FPETFO) based on EID estimator, and MRC based on EID estimator with
adaptive periodic event triggered mechanism based fuzzy state observer
(APETM-FSO). The first scheme, MRC with PETFO based on EID has been
designed for linear systems subjected to unknown exogenous disturbances. The
second one, MRC with FPETFO based on EID has been proposed for a class of
time-varying delay nonlinear systems with unknown exogenous disturbances.
The last scheme, MRC based on EID with APETM-FSO has been considered for
a class of time-varying delay nonlinear systems subjected to unknown
exogenous disturbances.
The developed schemes achieve periodic reference tracking and improve the
performance of periodic and aperiodic unknown disturbances rejection
effectively. Moreover, Takagi-Sugeno (T-S) fuzzy model has been used to
approximate the time-varying delay nonlinear system. In addition to utilizing the
PETM to reduce data transmission, computational burden and to save communication resources. Then, set of sufficient conditions have derived to
guarantee the asymptotic stability of the overall system using the LyapunovKrasovskii functional (LKF) stability theory and linear matrix inequalities (LMIs).
Finally, numerical and simulated applications have illustrated the effectiveness,
feasibility and robustness of the proposed schemes.