• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.10
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• pp.1251-1258
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• 1999

The water level control of a steam generator in the unclear power plant is an important process. Most of the water level controllers of the actual plant are PID controllers. But they have limitations in appling for tracking the set point and getting rid of disturbances, so there are some defects to apply in the actual ground even though many research works represented the resolutions to solve it. In this paper, it is suggested that the established simple PID controller in low power has the ability to remove disturbances and trace the set-point, and then possesses the real-time self-tuning function according to the variety of moving peculiarity of a plant. This function realized by making use of fuzzy logic. PID parameters are formulated by a variable ${\alpha}$ and made it fluctuate by a fuzzy inference according to level error and level error change. This mechanism makes application of actual plant effective as well as taking advantage of improving the efficiency of water level controller by way of adding the function of self-tuning instead of replacing PID controller. The computer simulation of this scheme shows the improved performance compare to conventional PID controller.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.85.2-85
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• 2001

In this paper, we propose a modified Ziegler-Nichols PID controller using the fuzzy logic system. The proposed method is to parameterize a Ziegler-Nichols formula with a single parameter, and use the fuzzy logic system for automatic tuning of a single parameter of the modified Ziegler-Nichols formula. The fuzzy logic system has simple nine control rules. In order to verify the effectiveness of the proposed method, we simulated with the servo system. Simulation results demonstrate that better control performance can be achieved when compared with that of the Ziegler-Nichols PID controller.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.792-797
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• 2009

This paper presents the evaluation of PID and fuzzy control logic for the lateral position control of a moving web in roll-to-roll (R2R) printed electronics. In addition, we report the implementation of computer simulation software that enables us to develop the control logic in a graphic user interface and to test the controller performance in 3D dynamic environment. A mathematical model of the web dynamics is described first to explain the lateral motion of a moving web. Based on the model, PID and fuzzy controllers are designed, and embedded in the simulation software. Under the simulation conditions for fabricating RFID antenna by R2R printing, the results indicate that the fuzzy controller shows a better performance and can be more suitable for R2R multi-layer printed electronics.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1176-1181
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• 2007

In this paper, we consider one of robust control system, fuzzy PI+fuzzy D controller dealing with noise, load, changed parameters of plant. We apply PI+D controller with a design for output of differential function and, we plan fuzzy controller with input for PID parameter of PI+D controller so We design control system meet with the change of environment with robust in relation to change of parameter. Fuzzy control is possessed of easy 4 rules and membership function and We design fuzzy PI+fuzzy D controller. Plant of this paper make a choice of 3 phase induction motor.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2345-2348
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• 2003

This paper deals with a problem of automatic landing guidance and control system design. The auto-landing control system for the longitudinal motion is designed in the classical PID controller. The controller gains are properly adapted to variation of the performance using fuzzy logic as a gain scheduler for the PID gains. This control logic is applied to the problem of the automatic landing control system design. From the numerical simulation using the 6DOF nonlinear model of the associated airplane, it is shown that the auto-landing maneuver is successfully achieved from the start of the flight conditions: 1500 ft altitude, 250 ft/sec airspeed and zero flight path angle.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2333-2335
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• 2000

The main motivation of this research is to develop an intelligent control strategy for Activated Sludge Process(ASP). ASP is a complex and nonlinear dynamic system because of the characteristic of a wastewater, the change of an influent flow rate, weather conditions, and etc. The mathematical model of ASP also includes uncertainties which are ignored or not considered by process engineer or controller designer. The ASP is generally controlled by a PID controller that consists of fixed proportional, integral, and derivative gain values. The PID gains can be adjusted by the expert in the ASP. The ASP model based on Matlab$^{(R)}$5.3/Simulink$^{(R)}$3.0 is developed in this paper. Various control methods are applied to the ASP model and the control results are disscussed. Three control methods are designed and tested: conventional PID controller, fuzzy logic control approach to modify setpoints, and fuzzy-PID control method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.5
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• pp.1228-1234
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• 2015

In this paper, a fuzzy controller using thermoelectric for temperature environmental tester is developed. The new structure of fuzzy controller based temperature environmental tester is proposed and implemented to maintain a stable temperature and improve temperature change speed. In order to evaluate the efficiency, an experiment is setup to compare PID controller with our proposed controller. The experimental results, we proved that our proposed fuzzy controller has better performance than PID controller.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.35-42
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• 1998

This paper presents the introduction of Pseudo-2 axes robot module and its GA-based fuzzy control implementation. Pseudo-2 axes robot module which use a single motor and controller for driving 2 joints of a robot mechanism, is devised towards a lower priced robot with its degree of freedom maintained GA-based Fuzzy controller is considered for the better control implementation of the developed system than the conventional PID controller. Here. the scaling factors of the membership function with high fitness values are selected using a genetic algorithm for a pulse-type input trajectory. The obtained controller also shows better trajectory tracking performance than a PID controller.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.705-709
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• 2005

In this paper, we introduce fuzzy algorithm similar to human's way of thinking and designed collision detection system of vehicles. First, before the model vehicles design, we did simulation collision detection using PID and Fuzzy Controller. As a result, P.O that is Percent Overshoot when make use of PID controller happened from smallest 32% to 45%. But, In case of using fuzzy controller they produced about 10% in 7% in case use 25 rule. We designed model vehicles that introduce Auto Guided Vehicle(AGV) with confirmed result in simulation. We set Polaroid 6500 sensor on the front of model automobile because distinguish existence automobile to the head. And we composed motor drive part to run vehicles and 80C196KC processor for control movement of vehicles influenced on distance data of the front vehicles that receive from supersonic waves sensor. In case of using Fuzzy controller, last value percent error happened about maximum 15% in smallest 5%, and we confirmed that distance with front vehicles kept when state hold time is about maximum 16 seconds in smallest 10 seconds.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.404-407
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• 1993

In this paper, a new PID fuzzy controller(FC) is presented. The linguistic control rules of PID FC is separated into two parts : one is e-.DELTA.e part, and the other is .DELTA.$^{2}$e - .DELTA.e part. And then two FCs employing these rule base individually are synthesized. The control input to the process is decided by taking weighted mean of the outputs of two FCs. The proposed PID FC improve the transient response of the system and gives better performance than the conventional PI FC.