• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.306-306
• /
• 2000

This paper analyze the dynamic characteristics of Automated Guided Vehicle(AGV) which is being developed as a part of automation in port through DADS, one of the multi-dynamic analysis program, Previous evaluation of a vehicle is carried out through the continuous driving test of a real vehicle, however this method raise the loss of finance and time. If it is possible to analyze the dynamic characteristics of vehicle before construction completely we can compensate the loss of money and time during constructing. AGV contained containers is very heavy and its center of gravity can be easily changed with the disturbance from road or cornering. It makes AGV unsatisfied, therefore we evaluate the handling characteristics and stability of the full vehicle model. This paper contribute to establish the foundation of the development of a new system like a AGV which have a special structure.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.307-307
• /
• 2000

The swing motion of the spreader during and after movement causes an efficiency problem of position control in unmaned gantry crane. The objective of this research is to design implementable stabilizing controllers that minimize the swing motion of spreader in precise position control. The dynamic equations related to trolley, rope, and spreader are derived. For constitute a similar actual system, we introduced a conception of spring and damper in the connector. It is located between the trolley and link that is used in stead of rope. We derived dynamic equation by appliance that friction and external disturbance are occurred to the connector. We constituted of position servo system and velocity servo system for the control of position and velocity of the trolley and constituted of lag compensator system for the control of sway of the spreader. And we will show an effect of the proposed system in this research finally.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.362-362
• /
• 2000

The purpose of this thesis is to reduce force ripple of linear pulse motor(LPM) using neural network and to enhance precision. In order to this, we propose a new controller using a neural network to compensate disturbances. The structure includes adaptation block which learns the dynamics of the periodic disturbance and forces the interferences, caused by disturbances. The proposed controller compensates an unmodeled dynamics in the LPM. The neural network changes a current command to reduce position error and force ripple of the LPM. We compare proposed controller with PI controller. Simulation result shows that the proposed controller has better performance than a PI controller without neural network.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.10
• /
• pp.180-192
• /
• 1998

This paper introduces a new self-organizing fuzzy logic controller (SOFLC) for precision contour machining in the presence of large disturbances which adjusts both input and output membership functions simultaneously. The parameters of the proposed controller are self-tuned in real-time according to a continuous measurement of the performance of the controller itself and estimated disturbance values. The proposed controller as well as a conventional fuzzy logic controller and a PID controller were simulated and implemented on a 3-axis milling machine in contour milling. Both the simulations and experiments show that the self-organizing fuzzy logic controller has superior performance in terms of contour tracking accuracy compared with the other two controllers.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.04a
• /
• pp.426-429
• /
• 2003

This research introduces some preliminary results of bank filtering intake method adopted ill Backam area, Yongin city. This bank infiltration had been supplied to water resources of 750 m$^3$/day to Backam-myun, in 2002. It is believed that the bank infilteration method can afford to supply backam-myun people, Youngin city. The analysis of pumping data along the river shows the water supply pattern. Monitoring data of 1-6 pumping stations on the decline of water table along river sides and basic data on hydrogeologic properties are used to analyze the spatial disturbance range of groundwater systems due to the river pumping system.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.54 no.4
• /
• pp.228-234
• /
• 2005

In this paper, we proposed a self tuning adaptive fuzzy sliding control algorithms using gadient descent method to reduce chattering phenomenon which is viewed in variable control system. In design of FLC, fuzzy control rules are obtained from expert's experience and intuition and it is very difficult to obtain them. We proposed an adaptive algorithm which is automatically updated by consequence part parameter of control rules in order to reduce chattering phenomenon and simultaneously to satisfy the sliding mode condition. The proposed algorithm has the characteristics which are viewed in conventional VSC, e.g. insensitivity to a class of disturbance, parameter variations and uncertainties in the sliding mode. To demonstrate its performance, the proposed control algorithm is applied to an inverted pendulum system. The results show that both alleviation of chattering and performance are achieved.

• 전기의세계
• /
• v.49 no.9
• /
• pp.9-16
• /
• 2000

A receding horizon $H_{\infty}$ predictive control method is derived by solving a min-max problem in non-recursive forms. The min-max cost index is converted to a quadratic form which for systems with input saturation can be minimized using QP. Through the use of closed-loop prediction the prediction of states the use of closed-loop prediction the prediction of states in the presence of disturbances are made non-conservative and it become possible to get a tighter $H_{\infty}$ norm bound. Stability conditions and $H_{\infty}$ norm bounds on disturbance rejection are obtained in infinite horizon sence. Polyhedral types of feasible sets for sets and disturbances are adopted to deal with the input constraints. The weight selection procedures are given in terms of LMIs and the algorithm is formulated so that it can be solved via QP. This work is a modified version of an earlier work which was based on ellipsoidal type feasible sets[15].

• Proceedings of the KIEE Conference
• /
• 2001.07a
• /
• pp.125-127
• /
• 2001

In this paper, a robust $H_{\infty}$ optimal design problem under a structure-specified PSS is investigated for power systems with parameter variation and disturbance uncertainties. Immune algorithm is employed for optimization method of PSS parameter. It is shown that the proposed $H_{\infty}$-PSS tuned using immune algorithm is more robust than conventional PSS.

• Proceedings of the KIEE Conference
• /
• 2002.07d
• /
• pp.2824-2826
• /
• 2002

Immune system is an evolutionary biological system to protect innumerable foreign materials such as virus, germ cell, and etcetera. Immune algorithm is the modeling of this systems response that has adaptation and reliability when disturbance occur. In this paper, immune algorithm is proposed to control four wheels steering AGV(Automated Guided Vehicle) in container yard. The adaptive immune system is applied to the PID controller. For design the PID controller using immune algorithm, we tune PID parameters by off-line manner, in order to avoid the damage from abrupt control force. Repeatedly, the PID parameters are adjusted to be accurate by on-line fine tuner of immune algorithm. And then the computer simulation result from the viewpoint of yaw rate and lateral displacement are analyzed and compared with result of conventional PID controller.

• Journal of the Optical Society of Korea
• /
• v.20 no.3
• /
• pp.368-380
• /
• 2016

There is no doubt that adaptive optics (AO) is the most promising method to compensate wavefront disturbance in free space optics communication (FSO). In order to improve the performance of the AO system described by discrete-time linear system model with time-delay and implicit phase turbulent model, new controllers based on a Kalman filter and its extensions are proposed. Based on the standard Kalman filter, we propose a fading memory filter to deal with the ruleless strong interference; sequential and U-D filters are applied to reduce implementation complexity for the embedded controllers. Theoretical analysis and the numerical simulations show that the proposed fading memory filter can upgrade the performance for AO systems in consideration of the unforeseen strong pulse interference, and the sequential and U-D filters perform well compared with a Kalman filter.