• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1120-1124
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• 2005

We reviewed controllers with a time delay estimation in this paper. Time delay control (TDC) and sliding mode control (SMC) are well known robust control schemes. Basically, the TDC has a main characteristic called a time delay estimation from which we can estimate the total uncertainty of a system. . The TDC causes the stick-slip in the case of systems with a friction. The so-called TDCSA which are short for TDC with switching action was developed to reduce the stick-slip. The TDC has the additional switching action term in the TDC structure. In the other hand, the SMC dose not have a time delay estimation but instead it can estimate the system uncertainty through the switching action. The SMC has a difficulty to estimate the total uncertainty of a system because it does not have a time delay estimation. In order to solve the difficulty, some control schemes were developed. Among them, we need to focus our attention on two control schemes: SMCPE and SMCTE, which are short for sliding mode control with a perturbation estimation and sliding mode control with a time delay estimation, respectively. In this paper, we analyzed and compared the characteristic of above three controllers. Even though the motives for the development of three control schemes are different, three control schemes have much in common in terms of their controller structures.

• 한국해양공학회지
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• 제11권4호
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• pp.169-179
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• 1997

This paper presents a discrete-time sliding mode control of an autonomous underwater vehicle with parameter uncertainties and long sample interval based on discrete variable structure system. Although conventional sliding mode montrol techniques are robust to system uncertainties, in the case of the system with long sample interval, the sliding control system reveals chattering phenomenon and even makes the system unstable. This paper considers the AUV which acquires position informations from a surface ship through an acoustic telemetry system with a certain discrete interval. The control system is designed on the basis of a Lyapunov function and a sufficient condition of the switching gain to make the system stable is give. Each component of the switching gain can be determined separately one another. The controller is robust to the uncertainties, and reaching condition of the control system is satisfied for any initial condition. This control law is a generalized form of the discrete sliding mode control and reduce the chattering problem considerably. Motion control of the AUV in the vertical plane shows the effectiveness of the proposed technique.

• 한국소음진동공학회논문집
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• 제17권12호
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• pp.1152-1160
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• 2007

이 논문에서는 선형 유도 모터로 추진되는 자기부상 열차 시스템에서 열차의 속도에 따라서 추진 시스템으로부터 발생하는 간섭력의 부상 시스템에 대한 영향을 최소화하기 위한 적분형 sliding mode 부상제어기의 설계에 대해서 다룬다. 제어기 구조는 적분형 제어기와 sliding mode 제어기로 구성된다. 적분형 제어기는 정적 외란에 대해서 정상상태 오차가 영에 도달하는 것을 보장하고 sliding mode 제어기는 수학적 모델이 본질적으로 갖고 있는 불확실성에 대한 강건성을 보장 한다 sliding mode 제어기의 chattering 문제를 해결하기 위해서 연속 함수를 도입한다. 선형 유도모터에 의한 간섭력은 실험 데이터의 curve fitting에 의한 수학적 모델링을 통하여 수식화 한다. 컴퓨터 모의시험을 통해서 설계돈 적분형 sliding mode 제어기의 효율성을 보인다.