Ahmed El Hajjaji

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This paper addresses robust observer based H<sub>infin</sub> control problem for Takagi-Sugeno fuzzy systems with time-varying norm bounded uncertainties. Sufficient relaxed conditions for synthesis of a fuzzy observer and a fuzzy controller for T-S fuzzy systems are derived in terms of a set of linear matrix inequalities (LMIs). In comparison with the(More)
An Adaptive Sliding Mode Control (ASMC) for a class of nonlinear Multi Input Multi Output (MIMO) systems is presented in this paper. In order to reduce the chattering phenomenon without deteriorating the tracking performance, the discontinuous term of the classical sliding mode law is substituted with an adaptive Proportional Derivative (PD) term. The(More)
In this paper, an Adaptive Type-2 Fuzzy Sliding Mode Control is designed for a class of nonlinear Multi-Input Multi-Output (MIMO) systems with unknown partially dynamics and in presence of external disturbances. To estimate the unknown functions, a Sliding Mode Control (SMC) combined with Type-2 Fuzzy Logic are developed. The discontinuous term of the(More)
This paper addresses the modeling and control of the air path system of diesel engines. We propose robust control for the diesel engine equipped with Exhaust Gas Recirculation (EGR) and Variable Geometry Turbocharger (VGT) systems. The goal is to control carefully the air flow for a diesel engine to reduce emissions of pollutant particles and fuel(More)
This paper presents a robust method for estimation the lateral velocity of vehicle. The proposed observer describes a simple structure that contains a sliding mode term which turns out to be robust against output noises and parameters variations as well as sustained disturbances The given nonlinear model of the vehicle is then represented by an uncertain(More)
This paper deals with sufficient conditions of asymptotic stability for non linear discrete-time 2D systems represented by a Takagi-Sugeno fuzzy model of Roesser type with state feedback control. This work is based on common and multiple Lyapunov functions. The results are presented in LMI's form.
This paper focuses on the control of diesel HCCI engine air path. We propose a control strategy based on Recursive Model Free Controller (RMFC). This kind of controller is simple to design and it needs only the outputs of the system. On other hand, in order to estimate the state variables, an observer is used and its convergence is performed by using(More)
This paper deals with the problem of delay-dependent stability and stabilization of Takagi-Sugeno (T-S) fuzzy systems with a time-varying delay. A new method which brings three great advantages for the T-S delay-dependent stabilization problem is developed. The first one is that this method is less conservative than other existing ones. The second one is(More)
This paper presents a sum of squares (SOS) approach to stability analysis of polynomial fuzzy systems with time-delay. Based on a novel polynomial Lyapunov-Krasovskii Functional, stability conditions are presented in terms of sum of squares in order to reduce the conservatism. The proposed SOS-based framework is more innovative and effective than the(More)
This paper investigates the problem of robust control design for a class of uncertain nonlinear systems with delay. The system is described by a state-space Takagi-Sugeno fuzzy model and norm-bounded parameter uncertainties. By evaluating the derivative of a new fuzzy weighting-dependent Lyapunov-Krasovskii functional, less conservative convex conditions,(More)