• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.317-320
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• 1999

A robust end time optimal conかof strategy for dual-stage servo system is presented. The time optimal trajectory for a mass-damper system is determined and given os a reference input to the servo system. The feedback controller is constructed so that the fine stage tracks the coarse stage errors and robustly designed as the“perturbation compensated sliding mode control(PCSMC)”law, a combination of slid-ing mode controller(SMC) and perturbation observer(PO). In addition, a null motion controller which regulates the fine stage at its neutral position is designed based on the“dynamic consistency”So, the overall dual-stage servo system exhibits the robust and time-optimal performance. The inherent merit and performance of the dual-stage system will be shown.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.1
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• pp.67-73
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• 2002

This paper presents the development of development of stabilization and tracking algorithms for a shipboard satellite antenna system. In order to stabilize the satellite antenna system designed in the previous work, a model for each control axis is derived and its parameters are estimated using a genetic algorithm, and the state feedback controller is designed based on the linearized model. Then a tracking algorithm is derived to overcome some drawbacks of the step tracking. The proposed algorithm searches for the best position using gradient-based formulae and signal intensities measured according to a search pattern. The effectiveness of both the stabilization and tracking algorithms is demonstrated through experiment using real-world data.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.30-35
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• 1990

Learning control of a robot manipulator is proposed using the backpropagation neural network. The learning controller is composed of both a linear feedback controller and a neural network-based feedforward controller. The stability analysis of the learning controller is presented. Three energy functions are selected in teaching the neural network controller : 1/2.SIGMA.vertical bar torque error vertical bar $^{2}$, 1/2.SIGMA..alpha. vertical bar position error vertical bar $^{2}$ + .betha. vertical bar velocity error vertical bar $^{2}$ + .gamma. vertical bar acceleration error vertical bar $^{2}$ and learning methods are presented. Simulation results show that the learning controller which is learned to minimize the third energy function performs better than the others in tracking problems. Some properties of the learning controller are discussed with simulation results.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.175-180
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• 2005

Incorrections between model and plant are parameter, system order uncertainties and modeling error due to disturbance like friction. Therefore to achieve a good tracking performance, adaptive discrete time sliding mode tracking controller is used under time-varying desired position. Based on the diophantine equation, a new discrete time sliding function is defined and utilized for the control law. Robustness is increased by using both a recursive least-square method and a sliding function-based nonlinear feedback. The effectiveness of the proposed control algorithm is proved by the results of simulation and experiment.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.4
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• pp.126-135
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• 1992

Up to now, there has been a lot of researches on the sliding mode control which has the insensitive characteristics to the variations of plant parameters, nonlinearities and external disturbances. One difficulty in applying the sliding mode control is the need for the knowledge of the full-state vector. The use of state observer is a natural step towards the relaxation of this condition. However, the exact plant-modeling is assumed to be known. Recently, there has been a remarkable advance in the microprocessor and one can construct the controller which could not realize due to hardware restriction in the past. Therefore in this paper, the PID sliding mode controller which has only one output feedback signal is suggested by means of microprocessor and the performance of electro-hydraulic servosystem compensated with this controller is proved.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.11
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• pp.591-598
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• 2000

In this thesis, a digital tracking controller is proposed for multi-axis position control system. Tracking and contouring error exist when the machine tool moves along a trajectory in multi-axis system. The proposed scheme enhances the tracking and contouring performance by reducing the errors. Also, an optimal tracking controller reduces the tracking error by the state feedback and the feedforward compensator reduces the effects of a nonlinear disturbance such as friction or dead zone. The proposed control scheme reduces the contour error which occurred when the tool tracks the reference trajectory. Finally, the performance of the proposed controller is exemplified by some simulations and by applying the real XY servo system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.407-414
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• 1996

In this paper we consider the variable structure control for a class of discrete-time uncertain multivariable systems where the nominal system is linear. Discrete-time switching dynamics are introduced so that a new type of state trajectories called sliding mode may exist on the sliding surface by state feedback. The quantitative analysis for the matched uncertainties will show that every response of the system with the proposed switching dynamics is bounded within small neighborhoods of the state-space origin. Also, by the similarity transformation it will be shown that the eigenvalues of the closed-loop systems are composed of those of the subsystems which govern the range-space dynamics and null-space dynamics. It will be also shown that ideal sliding mode can be obtained in the absence of uncertainties due to one-step attraction to the sliding surface regardless of initial position of states. (author). 12 refs., 2 figs.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.3
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• pp.307-312
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• 2010

In this study, advanced computational technique for mechatronic analysis has been developed for the efficient design and test of typical machine tool models. Flexible multi-body dynamic (FMBD) analysis method combined with motion controller including control logics is used to simulate typical operation conditions. The present FMBD machine tool model is composed of flexible column structure, rigid body spindle, vertical motion guide (arm) and screw elements. Driving motor clement with rotating degree-of-freedom is interconnected and governed by the designed Matlab Simulink control logic, and then the position of the spindle is feedback into the control logic. It is practically shown from the results that the investigation of designed machine tools with controller can be effectively conducted and verified.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.256-259
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• 1987

In this paper, a servo controller for a robot manipulator is developed. It consists of a conventional MRAS controller for each joint together with a feedback control to Dynamics compensation. To generale the control torque effectively a currant drive method is adopted. The speed of the actuator is measured by using a tachometer and the position of the link is measured by using a potentiometer. To show the effectiveness of the proposed control algorithm the proposed controller is tested in real time.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2983-2985
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• 1999

This paper presents the attitude control of the double inverted pendulum with compliant joint. The biped robot with compliant ankle joint instead of a motor have a good contact between it's sole and ground in the uneven ground. The compliant ankle joint proposed here is composed of springs and mechanical constraint. The lower link is hinged on the plate to free for rotation in the vertical plate. The upper link is connected to the lower link through a DC motor. The DC motor is used to control the posture of the pendulum by adjusting the position of the upper link. The algorithm for controlling a proposed inverted pendulum is nonlinear feedback controller. Simulation with mathematical model are conducted to show the validity of the proposed controller.