2024-03-28T12:34:55+03:30 http://joc.kntu.ac.ir/browse.php?mag_id=27&slc_lang=fa&sid=1
27-124 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Design and Implementation of Hardware in the Loop Tester for a Tactical Missile Flight Computer with Hybrid Guidance amir yaghoobi yaghoobicontrol@gmail.com Mohammadreza Arvan arvan@mut.ac.ir Abbas Taghipoor ataghipoor2006@yahoo.com Ali Nassrollahi alinasrollahi544@gmail.com One of the most common methods in development and evaluation of aerospace systems is the hardware in the loop (HWIL) test which the part of the system that must has been developed or evaluated its performance, are in hardware and other parts of the system are in software mode put in the flight simulation loop. This test is a closed-loop and real-time simulations that for its implementation, a platform named hardware in the loop test are used. In this paper the design and implementation of HWIL tester of a tactical missile flight computer system with hybrid guidance is presented. Flight computer is an essential subsystem of missile that calculations of guidance and control are done in it. This subsystem for guidance and control algorithms Implementation, collect data from seeker and other missile sensors including free gyroscopes that measure rolling angle, potentiometer of control fins and sending the appropriate commands to actuators for correcting the path of missile. For verifying the performance of this flight computer can use open loop and close loop tests. In this paper for close loop verifying of flight computer, a HWIL tester, is designed and implemented. This tester consists of two parts: hardware and software that aims to create conditions close to reality for evaluating the performance of flight computer hardware. After design of this tester, its results are compared with results of six degree of freedom missile simulation in various scenarios that the appropriate consistency of results shows the accuracy of planning. Flight computer HWIL tester 6DOF Simulation DSP processor. 2015 3 01 1 13 http://joc.kntu.ac.ir/article-1-124-en.pdf
27-176 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Distributed Optimal Control of Nonlinear Differential Graphical Games based on Reinforcement Learning Farzaneh Tatari fa_tatari@yahoo.com Mohammad-B Naghibi-S mb-naghibi@um.ac.ir This paper introduces continuous time nonlinear differential graphical games and proposes an online distributed optimal control algorithm to solve them. In differential graphical games, each agent error dynamics and performance index depend on its neighbors’ information. The proposed online distributed policy iteration algorithm solves the cooperative coupled Hamilton-Jacobi equations. In this algorithm which is based on reinforcement learning, each agent uses an actor-critic neural network structure where the weights of these neural networks are tuned synchronously. While all actor-critic networks are learning, closed loop stability and convergence to optimal control laws are guaranteed. Finally simulation results demonstrate the validity and performance of the proposed algorithm. Artificial neural networks Nonlinear differential graphical games Optimal control Reinforcement learning. 2015 3 01 15 30 http://joc.kntu.ac.ir/article-1-176-en.pdf
27-180 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Optimal Glucose-Insulin Regulatory System in Type1 Diabetic Patients Based on the Nonlinear Time Delay Models Mohamad Sadegh Akhyani sadegh_akhyani@ee.kntu.ac.ir Hamid Khaloozadeh h_khaloozadeh@kntu.ac.ir In recent decades, control systems theory is used in many industrial and medical issues. Various control strategies are applied to this medical issues such as diabetes which is used to maintain normal glycemia in the patients suffering from diabetes. Obtain the appropriate insulin infusion rate in order to keep the patient’s glucose levels within predefined limits is always an interesting subject for physicians. Nonlinear time delay differential equations are well known to have arisen the diabetic patient modeling. Nonlinear time delay modeling leads to a small number of equations, but the control method will be far more complex. In this paper a new technique is introduced to solve optimal control in nonlinear time delay systems, called ESDRE. A nonlinear state feedback is designed to track the desired glycemia for a diabetic patients based on pseudo linearization method. This method gives suboptimal solution for the problem. The stability of the closed-loop systems based on the ESDRE technique is also studied. Using this method, the optimal insulin infusion rate as the control signal is obtained and glycemia in type1 diabetic patients converges to the desired normal range. The results of the proposed method are compared with the Palumbo's nonlinear controller which is based on feedback linearization. The results of the simulations, represents the efficiency of the proposed method. Optimal control of diabetic patient Nonlinear time delay systems Pseudo linearization DDE models ESDRE method 2015 3 01 31 41 http://joc.kntu.ac.ir/article-1-180-en.pdf
27-191 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Control Of Wind Turbine With Double Fed Induction Generator To Track For Maximum Wind Power Mahmood Abolhasani zarjoo mahmood.pe@gmail.com Seyed Babak Mozafari mozafari_babak@yahoo.com Turaj Amraee amraee@kntu.ac.ir Among renewable energies, wind energy has attracted more attention since 1991. The main objective for utilization of the wind plant is to reduce cost and environment pollution. It is well known that the power delivered by wind turbines which are directly coupled with grid is not constant as a result of wind variability. Thus in spite of sudden wind speed variations, farm generators should always be capable of extracting maximum possible mechanical power from the wind and converting it in to electrical power. Variable speed wind turbines are commonly equipped with doubly fed induction generators (DFIG). In fact, doubly fed induction generators are wound rotor induction generators that their stators are connected to grid directly and their rotors are connected to grid through two PWM back to back power electronic converters. This thesis focuses on control of a grid-connected doubly fed induction generator (DFIG) based wind turbine system in order to track maximum absorbable power in different wind speeds. First, the dynamic model of wind turbine, gear box and DFIG is developed. Then, a generalized regression neural network (GRNN) is used to estimate wind speed and the maximum absorbable power is determined through a look up table for per wind speed. Finally vector control employs PI controller to calculate the required rotor control voltage for control of active and reactive power and obtaining maximum power from wind turbine. Simulation results on 1-MW wind turbine are provided and show the effectiveness of the new technique, for tracking maximum power. Also, this scheme has acceptable harmonic spectra of stator current from the perspective power quality. MATLAB/Simulink(R2012b) software has been used for simulating. Wind Turbine Doubly Fed Induction Generator Vector Control Neural Network. 2015 3 01 43 53 http://joc.kntu.ac.ir/article-1-191-en.pdf
27-186 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Robust Stabilization of Switched Linear Systems, Based on State Feedback Observer and Dwell Time Switching Signal Mohamad Ali Bagherzadeh ma.bagherzadeh@ec.iut.ac.ir Jafar Ghaisari ghaisari@cc.iut.ac.ir Javad Askari j-askari@cc.iut.ac.ir Mohsen Mojiri mohsen.mojiri@cc.iut.ac.ir Stabilization of switched linear systems is one of the most important problems in the area of switched systems. In this paper, a design method for robust stabilization of parametric uncertain switched linear systems is proposed in terms of linear matrix inequalities. First, a method is proposed assuming that all states are available. This method designs the state feedback gains, such that the closed-loop system to be robustly asymptotically stable under switching signals with the known minimum dwell time. Since the states are unmeasurable in some practical systems, the method is then extended to the practical cases, in which the outputs are just available. The observer-based stabilizing state feedback gains are designed to stabilize such systems robustly for dwell time switching signals. The asymptotic stability of the proposed methods is proved under the assumption that all the nominal subsystems are controllable and observable. Then, the method is also generalized for robust stabilization of uncertain switched linear systems under any arbitrary switching signal. The correctness and effectiveness of the results are illustrated by some numerical examples. Switched linear system parametric uncertainty robust stabilization observer-based state feedback dwell time switching signals 2015 3 01 55 64 http://joc.kntu.ac.ir/article-1-186-en.pdf
27-205 2024-03-28 10.1002
Journal of Control JoC 2008-8345 2538-3752 10.52547/joc 2015 8 4 Performance Improvement of Uncertain TCP-Networked Control Systems Using Robust AQM Masoumeh Azadegan azadegan64@gmail.com Mohammad Taghi Hamidi Beheshti mbehesht@modares.ac.ir Babak Tavassoli tavassoli@eetd.kntu.ac.ir Abstract: This paper presents AQM design to improve the performance of networked control systems. An analytical model of the transmission control protocol (TCP) network is considered and a PID-type state feedback controller is developed to regulate the queue length. This leads to keeping network induced delay and its variation to be small enough to improve the overall performance of the NCSs. The model is assumed to possess structured uncertainties due to the stochastic nature of the network. By augmenting the TCP model with the plant equations, the closed loop system is transformed to a state-dependent delay differential equation (SDDDE). Applying the Lyapunov-Krasovskii method, a sufficient condition for the stability of this class of systems is obtained in terms of linear matrix inequality (LMI). PID controller parameters will be determined by solving these LMIs. Simulation results are presented and it has been shown that maximum allowable bound of time delay will increase in the proposed method. Uncertain Networked control systems Active queue management Linear matrix inequality Lyapunov-Krasovskii 2015 3 01 65 76 http://joc.kntu.ac.ir/article-1-205-en.pdf