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    • List of Articles Ahmad Fakharian

      • Open Access Article

        1 - Design and Simulation of Adaptive Neuro Fuzzy Inference Based Controller for Chaotic Lorenz System.
        Mehran Adibzadeh Ahmad Fakharian
        < p>Chaos is a nonlinear behavior that shows chaotic and irregular responses to internal and external stimuli in dynamic systems. Chaos appears in the system which is very sensitive to initial condition. Study of chaos dynamic systems has quickly spread in the las More
        < p>Chaos is a nonlinear behavior that shows chaotic and irregular responses to internal and external stimuli in dynamic systems. Chaos appears in the system which is very sensitive to initial condition. Study of chaos dynamic systems has quickly spread in the last three decades, and it has become a very attractive area of research to remove dynamic chaotic behaviors and make nonlinear systems stable. Stabilization has been considered as a high usage tool to eliminate aberrant behaviors of chaotic system and can be divided into two categories, regulation and tracking. In regulation stabilizing, system becomes stable by designing proper control signals to one of the available balance points or one of the alternate unstable paths on strange absorbers in chaos system. Another set of chaos systems stabilizing is tracking. In this type of stabilization, a reference signal varying with time and a control frame are considered in the way the system responses follow that signal. In this thesis, both regulation and tracking stabilizing are considered, first without chaos and then with chaos. For this purpose, smart and powerful adaptive neuro fuzzy inference system (ANFIS) technic is used. The proposed method is examined by a famous example of a chaos system called the Lorenz system. The simulation results show the ability of the proposed method. Our proposed approach is ANFIS which is designed for Lorenz chaotic system. it is compare with PID controller in the system . Manuscript profile
      • Open Access Article

        2 - Solving linear and nonlinear optimal control problem using modified adomian decomposition method
        Ahmad Fakharian Mohammad Taghi Hamidi Beheshti
        First Riccati equation with matrix variable coefficients, arising in optimal and robust control approach, is considered. An analytical approximation of the solution of nonlinear differential Riccati equation is investigated using the Adomian decomposition method. An app More
        First Riccati equation with matrix variable coefficients, arising in optimal and robust control approach, is considered. An analytical approximation of the solution of nonlinear differential Riccati equation is investigated using the Adomian decomposition method. An application in optimal control is presented. The solution in different order of approximations and different methods of approximation will be compared respect to accuracy. Then the Hamilton-Jacobi-Belman (HJB) equation, obtained in nonlinear optimal approach, is considered and an analytical approximation of the solution of it using the Adomian decomposition method is presented. Manuscript profile
      • Open Access Article

        3 - Solving Path Following Problem for Car-Like Robot in the Presence of Sliding Effect via LMI Formulation
        Masoud Emam Ahmad Fakharian
        One of the main problems of car-like robot is robust path following in the presence of sliding effect. To tackle this problem, a robust mix H2/H∞ static state feedback control method is selected. This method is the well-known linear robust controller which is robu More
        One of the main problems of car-like robot is robust path following in the presence of sliding effect. To tackle this problem, a robust mix H2/H∞ static state feedback control method is selected. This method is the well-known linear robust controller which is robust against external disturbance as well as model uncertainty. In this paper, the path following problem is formulated as linear matrix inequality for the kinematic model of car-like robot, which includes sliding effect. The robustness and path following performance of the proposed controller are investigated based on the comparison of suggested controller with an optimal proportional integral controller. The simulation results, which have been performed by MATLAB Simulink, shows the presented controller is able to follow various paths including simple, linear and more complex function path like square, and sine function path even in the presence of sliding effect. In addition, the robustness and correctness of closed-loop system in the simulations are demonstrated based on the nonlinear analysis of equilibrium point. Manuscript profile