• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.92.1-92
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• 2001

Sliding mode control of spacecraft attitude tracking with actuator, especially reaction wheel, is presented. The sliding mode controller is derived based on quaternion parameterization for the kinematic equations of motion. The reaction wheel dynamic equations represented by wheel input voltage are presented. The input voltage to wheel is calculated from the sliding mode controller and reaction wheel dynamics. The global asymptotic stability is shown using a Lyapunov analysis. In addition the robustness analysis is taken for nonlinear system with parameter variations and disturbances. It is shown that the controller ensures control objectives for the spacecraft with reaction wheels.

• International Journal of Control, Automation, and Systems
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• v.4 no.5
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• pp.545-558
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• 2006

In this paper, PD-like visual servoing is modified in two ways: a sliding-mode observer is applied to estimate the joint velocities, and a RBF neural network is used to compensate the unknown gravity and friction. Based on Lyapunov method and input--to-state stability theory, we prove that PD-like visual servoing with the sliding mode observer and the neuro compensator is robust stable when the gain of the PD controller is bigger than the upper bounds of the uncertainties. Several simulations are presented to support the theory results.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.624-627
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• 2000

An adaptive fuzzy sliding-mode control system which combines the merits of sliding-mode control the fuzzy inference mechanism and the adaptive algorithm is proposed. A fuzzy sliding-mode controller is investigated in which a simple fuzzy inference mechamism is used to estimate the upper bound of uncertainties., The fuzzy inference mechanism with centre adaptation of membership functions is investigated to estimate the optimal bound of uncertainties.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.474-477
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• 1995

In this paper, the nonlinear model of axial electro-magnetic suspension(EMS) system is presented. The characteristic of attracyion force is analyzed by FEM. Some simulation is given to compare the sliding mode control based on the input-output linearization with the classical linear control using Taylor approximation. Real result of regulating control, transient response comparison, and robustness control with disturbance using the sliding mode method is presented.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.130.5-130
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• 2001

This paper presents a discrete-time sliding mode control method for linear time-invariant systems with matched uncertainties. In this paper, we suggest a method of adding a command generator using input shaping filter to a discrete-time sliding mode controller. We design the number of steps required to reach the sliding layer and the magnitude of a control input, respectively using the shaping filter. Therefore we can minimize the excitation of the resonance mode and increase the tracking performance of a system. Simulation results are included to show its effectiveness.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.387-387
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• 2000

In this paper, we present a model reference sliding mode control for the system with input/output disturbance. The proposed model reference sliding mode control makes always the error remain on the surface in finite time. Therefore the system is insensitive to external disturbance. Simulation results are included to illustrate the effectiveness of proposed scheme.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.161-167
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• 2001

This paper presents an approach to nonlinear engine idle controller and intake manifold absolute pressure(MAP) observer based on mean torque production model. A stable engine idle speed is important in that the unstable engine Idle mode can make engine to drooping or stall state. A sliding fuzzy controller has been designed to control engine idle speed under load disturbance. A sliding observer is also developed to estimate the intake manifold absolute pressure and compared with the actual MAP sensor value. The sliding mode observer has shown good robustness and good tracking performance. The inputs of sliding fuzzy controller are the errors of rpm and MAP. The output is a duty cycle(DC) for driving a idle speed control valve(ISCV).

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.332-332
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• 2000

In this paper, a novel sliding mode control with uncertainty adaptation is produced by introducing a virtual state. Because upper bounds of the uncertainty is difficult to know, we estimate these upper bound by using the simple adaptation law and design the novel sliding mode controller. The nominal controller is used the optimal controller to minimize cost function.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.684-688
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• 1996

In this paper, to overcome drawbacks of variable structure control system a self-tuning fuzzy sliding mode control algorithm using gradient descent method is proposed. The proposed method 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 a one-degree of freedom robot arm. The results show that both alleviation of chattering and performance are achieved.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.22.4-22
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• 2001

In this paper, the discrete optimal control is made to have the robust property of sliding mode controller. A augmented system with a virtual state is constructed for this objective and noble sliding surface is constructed based on this system. The sliding surface is the same as the optimal control trajectory in the original system. The states follow the optimal trajectory even if there exist uncertainties. The reaching phase problem of sliding mode control is desappear in this method.