• Journal of Institute of Control, Robotics and Systems
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• v.3 no.2
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• pp.124-131
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• 1997

This paper presents a modified adaptive control scheme that improves the transient performance of the overall system while maintaining the asymptotic convergence of the output error. The proposed control scheme is characterized as the added outer dynamic feedback loop on the conventional adaptive control scheme. This control scheme enables various robust control methods that were developed for standard model reference adaptive controllers to be applied to the proposed controller. In contrast with the modified adaptive controllers that use augmented errors to provide additional dynamic feedback, the proposed controller uses tracking error directly, thereby reducing the tracking error significantly in the transient state and making the error insensitive to noise.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.12
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• pp.1306-1316
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• 1990

A controller using a multilayer neural network is proposed to the dynamic control of a PUMA 560 robot arm. This controller is developed based on an error back-propagation (BP) neural network. Since the neural network can model an arbitrary nonlinear mapping, it is used as a commanded feedforward torque generator. A Proportional Derivative (PD) feedback controller is used in parallel with the feedforward neural network to train the system. The neural network was trained by the current state of the manipulator as well as the PD feedback error torque. No a priori knowledge on system dynamics is needed and this information is rather implicitly stored in the interconnection weights of the neural network. In another experiment, the neural network was trained with the current, past and future positions only without any use of velocity sensors. Form this thim window of position values, BP network implicitly filters out the velocity and acceleration components for each joint. Computer simulation demonstrates such powerful characteristics of the neurocontroller as adaptation to changing environments, robustness to sensor noise, and continuous performance improvement with self-learning.

• 전기의세계
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• v.25 no.5
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• pp.70-74
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• 1976

In this paper, the problem of controlling deterministic contimuous linear system with a slightly modified quadratic performance criteria is studied. When the number of out put variables is much lesser then that of state variables, either the controller becomes complex or the performance measure becomes much higher with only output feedback. So the design philosphy treated in this paper lies in finding a compromising point between the controller complexity and the performance measure. thd controller is composed of stasic plus dynamic compensator with order equal to the mtmber of output variables. Several unknowns are unknown parameters are bundled into one, and using Pontryagin's minimum principle, conditions and formula for optimum control are induced which are different from that of Kalman optimal regulator.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.947-952
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• 1993

A simplified pole-placement design method is developed by analysing dynamic characteristics of the switching dynamics. Unlike the design procedure of conventional pole-placement, in the proposed method, overall state-space is directly decomposed into two invariant subspaces by the projection operator which is defined in the equivalent system, and then the closed-loop poles are assigned to each subspace independently. Hence, computations for state-feedback gain matrix are easy and simple.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.4
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• pp.7-13
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• 1998

The gloval model is developed by combining this actuator formular with robot manipulator which is reported previously . The model initially represented in the form of coupled time-varying nonlinear dynamic system. It then decomposed into the decoupled linear model using nonlinear feedback and state transformation techniques. The new model employes the pole replacement method to improve the stability of the system. Using this new model, an robust control algorithm is developed. The proposed algorithm takes two state variables, position vector and velocity vector, and one input variable from actuator, input voltage.

• 전기의세계
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• v.30 no.8
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• pp.509-516
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• 1981

The optimal control theory is applied to the design of a digital control system for a nuclear reactor. A linear dynamic model obtained at 85% of rated power and a quadratic performance index are used. A minimal order observer used in cascade with the feedback controller is suggested as a state estimator. The total reactor power control is studied in the range of 80% to 100% of rated power, with the steady state and load-following control. The control algorithm considered is suitable for implementation in direct digital control.

• Journal of Mechanical Science and Technology
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• v.14 no.4
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• pp.369-379
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• 2000

In industrial production-distribution systems, production and purchasing rates, associated inventories, and sales are very critical for the profits of each component in the system. The objective of this study is to investigate an effective information control scheme for a production -distribution system by automatic feedback control techniques. In this work, a dynamic control scheme that has an integrated -error with state-feedback and filtering (ISFF) is proposed as a new algorithm for a dynamic controller. Generalized formulations of the dynamic control are proposed in the continuous-time and discrete-time cases. A methodology for an evaluation of ISFF controller gains using the eigen structure property is presented. When an upper-limit is imposed on the production capability by available factory space and capital equipment, supervisory control is provided to avoid integrator-windup and deterioration of system performance.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.501-503
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• 1996

In this paper, a novel control strategy for PWM current source converter and inverter is proposed, applying a multivariable state feedback control. The PWM converter controls line current to be sinusoidal and make input power factor unity. In addition, the modulation index control of dc link current is carried out, which produces lower loss of switching devices. Since the voltage control of inverter output filter capacitor is performed a decoupling of the d-q current of the induction motor is well retained. With the proposed algorithm, both high dynamic responses and satisfactory static performance can obtained.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1389-1399
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• 2013

A discrete controller is designed for low power dc-dc switched mode power supplies. The approach is based on time domain and the control loop continuously and concurrently tunes the compensator parameters to meet the converter specifications. A digital state feedback control combined with the load estimator provides a complete compensation, which further improves the dynamic performance of the closed loop system. Simulation of digitally controlled Buck converter is performed with MATLAB/Simulink. Experimental results are given to demonstrate the effectiveness of the controller using LabVIEW with a data acquisition card (model DAQ Pad - 6009).

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.5
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• pp.496-501
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• 2012

An equilibrium point of a WIP (Wheeled Inverted Pendulum) with changing its center of gravity is derived and validated by various numerical simulations. Generally, the WIP has two equilibrium points which are unstable and stable one. The unstable one is interested in this study. To keep the WIP over the unstable equilibrium point, the WIP is consistently being adjusted. A state feedback controller for the WIP needs a control reference for the equilibrium point. The control reference can be obtained by studying an equilibrium point of the WIP based on statics. By using Lagrange method, this study is deriving dynamic equations of the WIP both with and without changing its center of gravity. Various numerical simulations are carried out to show the validation of the equilibrium point.