• 제어로봇시스템학회논문지
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• 제7권12호
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• pp.1031-1035
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• 2001

In this paper, a robust recursive control approach for nonlinear system, which is based on Lyapunov stability, is proposed. The proposed method can apply to extended systems including cascaded systems and the stability is guaranteed in the sense of Lyapunov. The recursive design procedure so called “robust recursive control approach” is used to find a stabilizing robust controller and simultaneously estimate the uncertainty parameters. First, a nonlinear model with uncertainties whose bounds are unknown is derived. Then, unknown bounds of uncertainties are estimated. By using these estimates, the stabilizing robust controller is updated at each step. This approach is applied to the pitch autopilot design of a nonlinear missile system and simulation results indicate good performance.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.342-345
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• 2005

This paper describes dynamics analysis of a small training boat and a new type of ship's autopilot not only to keep her course but also to reduce her roll motion. Firstly, statistical analysis through multi-variate auto regressive model is carried out using the real data collected from the sea trial on an actual small training boat Sazanami after the navigational system of the boat was upgraded. It is shown that the roll motion is strongly influenced by the rudder motion and it is suggested that there is a possibility of reducing the roll motion by controlling the rudder order properly. Based on this observation, a new type of ship's autopilot that takes the roll motion into account is designed using the muti-variate modern control theory. Lastly, digital simulations by white noise are carried out in order to evaluate the proposed system and a typical result is demonstrated. As results of simulations, the proposed autopilot had good performance compared with the original data.

• 제어로봇시스템학회논문지
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• 제10권7호
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• pp.658-668
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• 2004

This paper is concerned with a control allocation strategy using the dynamic inversion and the pseudo inverse control which generates the nominal control input trajectories. In addition, an autopilot design method is proposed by using time-varying control technique which is time-varying version of the pole placement of linear time-invariant system for an agile missile with aerodynamic fin and thrust vectoring control. The control allocation proposed in this paper is capable of extracting the maximum performance by combining each control effector, aerodynamic fin and thrust vectoring control. The adopted time-varying control technique for the autopilot design enhances the robustness of the tracking performance for a reference command. The main results are validated through the nonlinear simulations with aerodynamic data.

• 한국항해학회지
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• 제19권3호
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• pp.11-19
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• 1995

When an automatic course keeping is introduced, as is quite popular in modern navigation, the closed-loop control system consists of autopilot device, power unit, steering gear, ship dynamics, and magnetic or gyrocompass. We derive mathematical models of each element of the automatic steering system. We provide a method of theoretical analysis on the propulsive energy loss related to automatic steering of ships in the open seas, taking account of the on-off(non-linear) characteristics of power unit. Also we paid attention to non-linear element installed in autopilot device, which is normally called weather adjuster. Next we make numerical calculation of the effects of autopilot control constants on the propulsive energy loss for two kinds of ship, a fishing boat and an ore carrier. Realistic sea and wind disturbances are employed in the calculation.

• 수산해양교육연구
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• 제19권3호
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• pp.510-516
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• 2007

The efficiency of magnetic compass direction sensor and magnetic compass by the laboratory experiment for the apparatus of generating artificial magnetic force and the onboard experiment on the fishing boat of coastal pot at the outside of Pusan Namhang were investigated. The results showed that the bearing angle of magnetic compass direction sensor was coincided with that of magnetic compass. However, the performance of magnetic compasses was unsuitable under the ISO rule by the characteristic experiment of damping curve. Therefore, the use of autopilot system using magnetic compass direction sensor which is based on the magnetic compass needs the sufficient notice.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1873-1874
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• 2008

본 연구는 근접상황의 선박 간 충돌회피시스템을 개발하기 위한 연구로서 근거리 조우상황에서 발생하는 선박충돌사고를 감소시키기 위한 선박충돌회피 설계방법을 제시한다. 이 설계모델은 레이다(Radar), 선박자동식별장치(AIS : Automatic Identification System)와 자동조타장치(Autopilot)를 충돌회피시스템에 연계하여 선박 간 충돌 사고를 사전에 예측하고 자동회피 방법을 제안한 것이다.

• 한국항해항만학회지
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• 제30권4호
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• pp.259-265
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• 2006

This paper presents an improved adaptive neural network autopilot based on our previous study for track-keeping control of ships. The proposed optimal neural network controller can automatically adapt its learning rate and number of iterations. Firstly, the track-keeping control system of ships is described For the track-keeping control task, a way-point based guidance system is applied To improve the track-keeping ability, the off-track distance caused by external disturbances is considered in learning process of neural network controller. The simulations of track-keeping performance are presented under the influence of sea current and wind as well as measurement noise. The toolbox for track-keeping simulation on Mercator chart is also introduced.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1995년도 VTS and IBS 95 The Korean Institute of Navigation 1995년도
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• pp.153-165
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• 1995

When an automatic course-keeping is introduced as is quite popular in modern navigation the closed-loop steering system consists of autopilot device power unit(or telemotor unit) steering gear ship dynamics and magnetic or gyro compass. We derive the mathematical model of each element of the automatic steering system. We provide a method of theoretical analysis on propulsive energy loss related to automatic steering of ships inthe open seas taking account of the on-off mechanism of power unit. Also we paid attention to dead band mechanism of autopilot device which is normally called weather adjustment. Next we make numerical calculation of the effects of autopilot control constants ont he propulsive energy loss for two kinds of ship a fishing boat and an ore carrier. Realistic sea and wind disturbances are employed in the calculation.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2019년도 추계학술대회
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• pp.264-264
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• 2019

해기사의 인적오류는 전체 해양사고 원인의 70% 이상을 차지한다. 해양사고 중에서 충돌사고는 막대한 인적/물적 손실을 야기하기 때문에 적극적인 예방이 필요한데, 특히 인적오류에 의한 충돌사고 예방이 시급한 실정이다. 현재, 선박에서 사용되고 있는 충돌회피장치에는, Autopilot, Track Control System, ARPA/Radar, ECDIS 등이 적용되고 있으나 항해사의 인적오류 예방 기능은 없다. 본 연구에서는 기존 Autopilot의 다양한 기능에 해기사의 인적오류를 예방할 수 있는 기능을 추가한 새로운 선박충돌회피 시스템(Human Collision Avoidance System, Hu-CAS)의 개발 개념을 소개한다. Hu-CAS는 1) 선박과 물표 사이의 충돌위험을 평가하는 부분과, 2) 충돌위험의 수준을 결정하는 의사결정 모듈, 3) 결정된 결과를 반영하여 선박의 제어 변수를 도출하기 위한 제어변수 추정 모듈, 4) 제어변수를 이용하여 선박의 타 각과 속력을 제어하는 제어 시스템 등으로 구성된다. Hu-CAS는 현재의 Autopilot을 대체할 수 있고, 미래 개발될 자율운항 선박과 유인선박 사이의 충돌회피 시스템으로 적용이 기대된다.

• 대한기계학회논문집
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• 제17권5호
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• pp.1123-1131
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• 1993

본 논문에서는 비행체의 사이드슬립(sideslip)의 변화를 최소로 하면서 롤(roll) 및 요(yaw) 운동을 제어하는 것을 제어목표로 하여, 입출력 갯수가 같은 정방(square)시스템과 입출력 갯수가 다른 비정방(nonsquare)시스템에 대하여 LQG/LTR 및 비례 재어기를 각각 설계하여 그 성능을 비교분석한다.