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Design and real-time experimental implementation of gain scheduling PID fuzzy controller for hybrid stepper motor in micro-step operation
, Article Proceedings of the IEEE International Conference on Mechatronics 2004, ICM'04, Istanbul, 3 June 2004 through 5 June 2004 ; 2004 , Pages 421-426 ; 0780385993 (ISBN) ; Alasty, A ; Sharif University of Technology
2004
Abstract
In this paper, design and real time experimental implementation of Fuzzy Gain Scheduling of PID controller for Hybrid Stepper Motor in Micro-stepping operation is described that was developed to track the desired positioning problem. The control problems characterized by mathematical models exhibit significant nonlinearity and uncertainty. Good performance of proposed Fuzzy PID controller are shown
Chaos control in continuous mode of T-AFM systems using nonlinear delayed feedback via sliding mode control
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings ; Volume 11 PART A , 2008 , Pages 201-208 ; ISBN: 079184305X ; Salaried, H ; Alasty, A ; Sharif University of Technology
Abstract
The taping mode Atomic Force Microscopic (T-AFM) can be assumed as a cantilever beam which its base is excited by a sinusoidal force and nonlinear potential interaction with sample. Thus the cantilever may cause chaotic behavior which decreases the performance of the sample topography. In order to modeling, using the galerkin method, the PDE equation is reduced to a single ODE equation which properly describing the continuous beam. In this paper a nonlinear delayed feedback control.is proposed to control.chaos in T-AFM system. Assuming model parameters uncertainties, the first order Unstable Periodic Orbits (UPOs) of the system is stabilized using the sliding nonlinear delayed feedback...
Emotional learning based intelligent controller for MIMO peripheral milling process
, Article Journal of Applied and Computational Mechanics ; Volume 6, Issue 3 , 2020 , Pages 480-492 ; Boroushaki, M ; Sharif University of Technology
Shahid Chamran University of Ahvaz
2020
Abstract
During the milling process, one of the most important factors in reducing tool life expectancy and quality of workpiece is the chattering phenomenon due to self-excitation. The milling process is considered as a MIMO strongly coupled nonlinear plant with time delay terms in cutting forces. We stabilize the plant using two independent Emotional Learning-based Intelligent Controller (ELIC) in parallel. Control inputs are considered as forces Ux and Uy in two directions x and y, which are applied by the piezoelectrics. The ELIC consists of three elements; Critic, TSK controller and the learning element. The results of the ELIC have been compared with a Sliding Mode Controller (SMC). The...
Integrated guidance and control of elastic flight vehicle based on robust MPC
, Article International Journal of Robust and Nonlinear Control ; 2014 ; Nikravesh, S. K. Y ; Haeri, M ; Sharif University of Technology
Abstract
Integrated guidance and control of an elastic flight vehicle based on constrained robust model predictive control is proposed. The design is based on a partial state feedback control law that minimizes a cost function within the framework of linear matrix inequalities. It is shown that the solution of the defined optimization problem stabilizes the nonlinear plant. Nonlinear kinematics and dynamics are taken into account, and internal stability of the closed-loop nonlinear system is guaranteed. The performance and effectiveness of the proposed integrated guidance and control against non-maneuvering and weaving targets are evaluated using computer simulations
Approximation behavior of Van der Pol equation: Large and small nonlinearity parameter
, Article IMECS 2011 - International MultiConference of Engineers and Computer Scientists 2011, 16 March 2011 through 18 March 2011 ; Volume 2 , March , 2011 , Pages 1539-1544 ; 9789881925121 (ISBN) ; Moghadas, P ; Rasouli, M ; Sharif University of Technology
2011
Abstract
The labels mathematician, engineer, and physicist have all been used in reference to Balthazar van der Pol. The van der Pol oscillator, which we study in this paper, is a model developed by him to describe the behavior of nonlinear vacuum tube circuits in the relatively early days of the development of electronics technology. Our study in this paper will be based entirely on numerical solutions. The rigorous foundations for the analysis (e.g., the proof that the equation has a limit cycle solution which is a global attractor) date back to the work of Lienard in 1928, with later more general analysis by Levinson and others
Duffing equations with cubic and quintic nonlinearities
, Article Computers and Mathematics with Applications ; Volume 57, Issue 3 , 2009 , Pages 500-506 ; 08981221 (ISSN) ; Hoseini, H ; Ahmadian, M. T ; Farrahi, G. H ; Sharif University of Technology
2009
Abstract
In this study, an accurate analytical solution for Duffing equations with cubic and quintic nonlinearities is obtained using the Homotopy Analysis Method (HAM) and Homotopy Pade technique. Novel and accurate analytical solutions for the frequency and displacement are derived. Comparison between the obtained results and numerical solutions shows that only the first order approximation of the Homotopy Pade technique leads to accurate solution with a maximum relative error less than 0.4%. © 2008 Elsevier Ltd. All rights reserved
Adaptive synchronization of two different chaotic systems with time varying unknown parameters
, Article Chaos, Solitons and Fractals ; Volume 37, Issue 1 , 2008 , Pages 125-136 ; 09600779 (ISSN) ; Shahrokhi, M ; Sharif University of Technology
2008
Abstract
In this paper a nonlinear control method based on Lyapunov stability theorem is proposed to design an adaptive controller for synchronizing two different chaotic systems. It is assumed that the unknown parameters of the drive and the response chaotic systems are time varying. It is shown that the proposed scheme can identify the system parameters if the system parameters are time invariant and the richness conditions is satisfied. To demonstrate the effectiveness of the proposed technique it has been applied to Lorenz-Chen dynamic systems, as drive-response systems. Simulation results indicate that the proposed adaptive controller has a high performance in synchronizing two chaotic systems....
Chaos control in continuous mode of T-AFM systems using nonlinear delayed feedback via sliding mode control
, Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 11 PART A , 2008 , Pages 201-208 ; 079184305X (ISBN); 9780791843055 (ISBN) ; Salaried, H ; Alasty, A ; Sharif University of Technology
2008
Abstract
The taping mode Atomic Force Microscopic (T-AFM) can be assumed as a cantilever beam which its base is excited by a sinusoidal force and nonlinear potential interaction with sample. Thus the cantilever may cause chaotic behavior which decreases the performance of the sample topography. In order to modeling, using the galerkin method, the PDE equation is reduced to a single ODE equation which properly describing the continuous beam. In this paper a nonlinear delayed feedback control is proposed to control chaos in T-AFM system. Assuming model parameters uncertainties, the first order Unstable Periodic Orbits (UPOs) of the system is stabilized using the sliding nonlinear delayed feedback...
Coupling between microring resonators in presence of Kerr effect
, Article Optics Communications ; Volume 281, Issue 9 , 2008 , Pages 2644-2650 ; 00304018 (ISSN) ; Bahrampour, A. R ; Farrahi Moghaddam, R ; Taraz, M ; Sharif University of Technology
2008
Abstract
The high degree of intensity values in microring resonators needs a careful treatment of nonlinear phenomena. Nonlinear effects are analyzed in coupling problem of ring-ring directional couplers. It has been observed that the nonlinearity affects the coupling device dramatically, and can be used as controlling techniques in such as coupled resonator optical waveguides. © 2007 Elsevier B.V. All rights reserved
Looking for systematic approach to select chaos tests
, Article Applied Mathematics and Computation ; Volume 198, Issue 1 , 2008 , Pages 73-91 ; 00963003 (ISSN) ; Esfahani, M. S ; Nojumi, H ; Sharif University of Technology
2008
Abstract
This paper will consider the mathematical definition of chaos (in sense of Devaney) in order to select appropriate chaos tests. The tests chosen according to investigate the properties mentioned in the definition. In fact, these are prerequisites of chaoticity. Either it will be represented that "sensitivity dependence on initial conditions" is not equivalent to chaos, although some researchers considering it. Hence, it is implied that checking all of the properties mentioned in the definition are required to establish chaos. As our case study, some sample stocks were selected from Tehran Stock Exchange (TSE) and the chosen tests implemented on their returns time series. Incoming results...
A genetic algorithm approach to optimize a multi-products EPQ model with discrete delivery orders and constrained space
, Article Applied Mathematics and Computation ; Volume 195, Issue 2 , 2008 , Pages 506-514 ; 00963003 (ISSN) ; Akhavan Niaki, S. T ; Sharif University of Technology
2008
Abstract
The economic production quantity (EPQ) is one of the most applicable model in production and inventory control environments. Like other classical production and inventory control models, it is derived based upon assumptions that cause limited real-world applications. Continuous and constant-rate delivery of orders, infinite availability of warehouse spaces, and applicability on a single product are some of these assumptions. In order to make the EPQ model more applicable to real-world production and inventory control problems, in this paper, we expand this model by assuming that the orders may be delivered discretely in the form multiple pallets. In addition, we may have more than one...
Position control of an ultrasonic motor using generalized predictive control
, Article 8th International Conference on Control, Automation, Robotics and Vision (ICARCV), Kunming, 6 December 2004 through 9 December 2004 ; Volume 3 , 2004 , Pages 1957-1962 ; 0780386531 (ISBN) ; Haeri, M ; Sharif University of Technology
2004
Abstract
Ultrasonic motors (USM) possess heavy nonlinear, and load dependent characteristics such as dead-zone and saturation reverse effects, which vary with driving conditions. These properties have made the position/velocity control of USM a difficult and challenging task. In this paper, a generalized model predictive (GPC) controller for precise USM position control is suggested. Simulation results indicate improved performance of the motor for both set point tracking and disturbance rejection. Since the motor and the controller both are of type one, the applied saturation would cause in wind up phenomenon. This drawback is removed by implementing the Quadratic GPC controller. © 2004 IEEE
Control of chaotic systems using fuzzy clustering identification and sliding mode control
, Article Applied Computational Intelligence - Proceedings of the 6th International FLINS Conference, Blankenberge, 1 September 2004 through 3 September 2004 ; 2004 , Pages 623-628 ; 9812388737 (ISBN); 9789812388735 (ISBN) ; Alasty, A ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2004
Abstract
In this paper we use a combination of fuzzy clustering estimation and sliding mode method to control a chaotic system, which its mathematical model is unknown. At first the model of chaotic system is identified without using any input noise signal. In this case the recurrent property of chaotic behavior is used for estimating its model. After estimating the fuzzy model of chaos, control and on-line identification of the input-related section is applied. In this step, we estimate the system model in normal form, such that the dynamic equations can be used in sliding mode control. Finally the proposed technique is applied to the Lorenz system as an example of chaotic system. The simulation...
Free chattering synchronization of two Lur'e differential inclusions with sector input nonlinearity
, Article 2014 IEEE Conference on Control Applications ; 2014 , PP. 1035-1040 ; ISBN: 9781479974092 ; Haeri, M ; Sharif University of Technology
Abstract
This paper deals with the synchronization of two Lur'e differential inclusions containing sector nonlinearity. Lyapunov stability theorem is employed to design the control inputs. The controllers are designed considering three important practical features in physical systems. First, differential equation part of the Lur'e differential inclusion is assumed to be convex. Second, it is presumed that parameters of the Lur'e differential inclusion are not completely known. Third, sector nonlinearities are considered on control inputs applied to the Lur'e differential inclusions. To assess performance and effectiveness of the proposed controllers, synchronization of two rotor dynamic systems is...
Model reference adaptive control design for a ducted fan air vehicle in vertical plane
, Article Applied Mechanics and Materials, 21 November 2012 through 22 November 2012 ; Volume 225 , November , 2012 , Pages 331-337 ; 16609336 (ISSN) ; 9783037855065 (ISBN) ; Banazadeh, A ; Sharif University of Technology
2012
Abstract
Ducted fan aerial vehicles have drawn many attentions in the world because of their successful involvement in non-traditional reconnaissance and surveillance missions. However, due to inherent dynamic uncertainties as well as inconsistent responses, significant control challenges are still to be addressed. In this study, a non-linear dynamic model for ducted fan is firstly proposed to be employed for control design. This model is then validated by performing a series of standard simulation scenarios. Afterwards, an adaptive control method, named as model reference is utilized to design perfect controllers in hover as well as vertical flight. The capability of the adaptive laws to update the...
Observer-based adaptive fuzzy controller for nonlinear systems with unknown control directions and input saturation
, Article Fuzzy Sets and Systems ; May , 2016 ; 01650114 (ISSN) ; Shahrokhi, M ; Khajeh Talkhoncheh, M ; Sharif University of Technology
Elsevier
2016
Abstract
This paper addresses design of an observer-based adaptive fuzzy controller for a class of single-input-single-output (SISO) nonlinear systems with unknown dynamics subject to input nonlinearity and unknown direction. The proposed controller is singularity free. A high-gain observer is designed to estimate the unmeasured states, and the Lipschitz condition for proving boundedness of the estimated states is relaxed. The Nussbaum function is used to handle the unknown virtual control directions and the backstepping technique has been applied for controller design. It is proved that all closed loop signals are semi-globally uniformly ultimately bounded (SGUUB) and the output tracking error...
Robust model predictive control of nonlinear processes represented by Wiener or Hammerstein models
, Article Chemical Engineering Science ; Volume 129 , 2015 , Pages 223-231 ; 00092509 (ISSN) ; Haeri, M ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Representing nonlinear systems by linear models along with structured or unstructured uncertainties and applying robust control strategies could reduce the computational complexity in comparison with implementing the nonlinear model predictive controllers. In this paper design of robust model predictive controllers which are based on special classes of nonlinear systems representations called Wiener and Hammerstein are presented. The proposed algorithms approximate the nonlinear systems by uncertain linear models and reduce online the computational demands in the control implementation. The advantages of the proposed approaches are illustrated by two examples
Application of the extended kantorovich method to the static deflection of microplates under capillary force
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 10 , November , 2010 , Pages 113-119 ; 9780791844472 (ISBN) ; Kahrobaiyan, M. H ; Ahmadian, M. T ; Sharif University of Technology
2010
Abstract
The aim of this paper is to apply an Extended Kantorovich method (EKM) to simulate the static deflection of microplates under capillary force. The model accounts for the capillary force nonlinearity of the excitation. Starting from a one term Galerkin approximation and following the Extended Kantorovich procedure, the equations governing the microplate deflection are obtained. These equations are then solved iteratively with a rapid convergence procedure to yield the desired solution. The effects of capillary force on the pull-in phenomenon of microplates are delineated in some figures. It is shown that rapid convergence, high precision and independency of initial guess function makes the...
Nonlinear modeling of piezoelectric layered beams
, Article Active and Passive Smart Structures and Integrated Systems 2007, San Diego, CA, 19 March 2007 through 22 March 2007 ; Volume 6525 , 2007 ; 0277786X (ISSN) ; Jalili, N ; Meghdari, A ; Sharif University of Technology
2007
Abstract
The dynamic equations of piezoelectric benders are studied in this paper, considering nonlinear behavior of piezoceramics. A second order approximation of constitutive equations of piezoceramics is used to account for reversible nonlinearities. Transversal and longitudinal deflections at the tip of the beam and the blocking force as well as sensor equations (output charge as a function of external loads) are obtained under static conditions. The static equations are then used to construct a linear dynamic model for actuation. A Bouc-Wen type hysteresis model is employed in order to account for the irreversible nonlinearities. The final equation of motion is in the form of well-known Hill's...
Free vibration analysis of functionally graded cylindrical shells including thermal effects
, Article Thin-Walled Structures ; Volume 45, Issue 6 , 2007 , Pages 591-599 ; 02638231 (ISSN) ; Mahmoudkhani, S ; Navazi, H. M ; Sharif University of Technology
2007
Abstract
Free vibration analysis of simply supported FG cylindrical shells for four sets of in-plane boundary conditions is performed. The material properties are assumed to be temperature-dependant and gradually changed in the thickness direction of the shell. The effects of temperature rise are investigated by specifying arbitrary high temperature on the outer surface and the ambient temperature on the inner surface of the cylinder. Distribution of temperature across the shell thickness is found from steady state heat conduction only in the thickness direction. The equations of motion are based on Love's shell theory and the von Karman-Donnell-type of kinematic nonlinearity. The static analysis is...