• 한국항해항만학회지
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• 제42권2호
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• pp.87-96
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• 2018

A trajectory control system plays an important role in controlling motions of marine vehicle when a series of way points or a path is given. In this paper, a sliding mode control (SMC)-based trajectory tracking controller for marine vehicles is presented. A small-sized unmanned ship is considered as a control object. Both speed and heading angle of a ship should be controlled for tracking control. The common point of related researches was to separate ship's speed and heading angle in control methods. In this research, a new control law from a general sliding mode theory that can be applied to MIMO (multi input multi output) system is derived and both speed and heading angle of a ship can be controlled simultaneously. The propulsion force and rudder force are also applied in modeling stage to achieve accurate simulation. Disturbance induced by wind is also tackled in the dynamics considering robustness of the proposed control scheme. In the simulation, we employed a way-point method to generate ship's trajectory and applied the proposed control scheme to ship's trajectory tracking control. Our results confirmed that the tracking error was converged to zero, thus demonstrating the effectiveness of the proposed method.

• 해양환경안전학회지
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• 제15권4호
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• pp.363-367
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• 2009

제한수역에서는 Bank cushion과 Squat의 작용으로 인하여 선체의 운동특성이 변한다. 실선을 통한 제한수역에서의 조종성능의 측정은 선박의 안전 때문에 어려운 실정이다. 본 연구에서 제한수역에서의 측벽효과와 Squat에 관한 정보를 얻기 위해 수치모델을 이용하여 선박의 운동을 모사하였다. 선박과 안벽의 거리가 좁을수록 선수방위는 많이 변하였다. 선수방위의 최대 변화치는 선폭에 대한 이안거리의 비(D/B)=0.2에서 $22.37^{\circ}$를 나타내었다. Squat는 속력이 빠를수록 흘수가 작을수록 커졌다. Squat의 최대치는 흘수에 대한 수심(H/d)=1.25, 속력 8knot일 때 0.29m였다. 선박의 안전운항을 위하여 제한수역에서는 감속이 가장 중요한 요소인 것으로 나타났다.

• 대한조선학회논문집
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• 제60권3호
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• pp.175-185
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• 2023

Many small vessels such as fishing boats operate in the world's oceans; accordingly, interest in these small vessels' exhaust-gas problem is increasing. Research on the application of electric-propulsion technology has been steadily conducted; however, the subject is limited to research ships or leisure boats, while research on application efficiency remains insufficient. This study attempts to apply lithium-battery electric-propulsion technology to small ships. A gross tonnage of 9.77, a representative fishing boat, is to be redesigned as a fully electrified ship. Without changing the main cabin's dimensions and fuel tanks, the ship's propulsion system is redesigned based on a lithium-battery electric-propulsion system. In addition, the redesigned system is compared with the original sample ship's diesel-propulsion system for application-effect analysis. The results indicate that under controlled sailing conditions, the weight and volume of the electric-propulsion system are 9.5 and 10.5 times those of the diesel-propulsion system, respectively. These values indicate that the system cannot meet fishing boats' high endurance requirements. Therefore, under the existing technical conditions, applying the full lithium-battery electric-propulsion system to solve the problem of high emissions from fishing boats shows limited feasibility.

• 한국항해항만학회지
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• 제29권10호
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• pp.827-832
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• 2005

본 연구는 근접상황 선박충돌회피지원시스템 개발을 위한 기초연구로써, 근거리 조우상황에서 항해사의 부적절한 조선으로 발생하는 선박충돌사고를 감소시키기 위한 선박충돌회피지원모델을 제시한다. 이 모델은 선박의 다양한 조우상황을 비교하고, 자선의 선회특성을 이용하여 상대선박의 침로, 속도 유지에 대한 충돌회피 가능영역과 방법을 나타냄으로써 근접상황에서도 신속한 피항동작 검토 및 결정을 가능케 하며 효과적인 충돌회피 조선을 지원할 것이다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 춘계학술대회 논문집
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• pp.119-124
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• 2005

본 연구는 근접상황 선박충돌회피지원시스템 개발을 위한 기초연구로써, 근거리 조우상황에서 항해사의 부적절한 조선으로 발생하는 선박충돌사고를 감소시키기 위한 선박충돌회피지원모델을 제시한다. 이 모델은 선박의 다양한 조우상황을 비교하고, 자선의 선회특성을 이용하여 상대선박의 침로, 속도 유지에 대한 충돌회피 가능영역과 방법을 나타냄으로써 근접상황에서도 신속한 피항동작 검토 및 결정을 가능케 하며 효과적인 충돌회피 조선을 지원할 것이다.

• 한국항해학회지
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• 제15권2호
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• pp.1-11
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• 1991

The ship's magnetic compass even if corrected is feasible to indicate the erroneous information due to the change of this ship's magnetism. But if the north-seeking sensor of the transmitting magnetic compass system is located where the effect of the ship's magnetism is the least , that problem is expected to be removed. In this paper, as a basic research to enhance the accuracy and the stability of the ship's magnetic compass by placing the north-seeking sensor at the adequate location, the theoretical model for the overall ship's magnetism were studied from the macroscopic viewpoint, The parameters of the theoretical model were determined by the least square method on the assumption that the overall magnetism of a ship can be regarded as that of the prolate spheroidal magnetic body. The agreement between the modelled and the observed values was found to be good.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.209-211
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• 2006

Auto Steering System is the device for course keeping or course altering to ship's steering system. The purpose of automatic steering system is to keep the ship's course stable with the minimum course and rudder angle. Recently, modern control theories are being used widely in analyzing and designing the ship system. Though P.D type auto pilots are widely used in ships, the stability and the adjusting methods are not clarified. In this paper the authors proposed auto steering system with Hybrid Controller. The things that the actual operators of a steering wheel has acquired through their experience can be logically described by the Lingustic Control Rule. The characteristic of the control system were investigated through the computer simulation results. it was found that the Hybrid control was more efficient than the PD control system.

• 한국항해항만학회지
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• 제35권2호
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• pp.131-136
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• 2011

As the faithful performance of ISPS of IMO, nowadays actually applicable an integrated safety and security system in and out of vessel should be organized in views of seafarers. Therefore, this paper is aimed to design a fundamental system for ship's integrated safety and security. The system of integrated grabbing will affect efficiently in any maritime field of material and human flow. Therefore this research will be expected to affect economical side by securing all the risk of maritime issues. In addition to the passenger ship and merchant vessel, it is applicable to other public and private vessels either. As a result of this paper, the system designed collecting various data through integrating the system including RFID reader, PIR sensor, and CMOS camera by putting an individual number into each unit that could be control at easy.

• 한국항만학회지
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• 제6권2호
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• pp.3-24
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• 1992

In the fuzzy control of shop the qualitative knowledge and information that the ship's operators have acquired through their experience can be logically described by the Linguistic control Rule (LCR). The algorithm of the control is made of the LCR and the control of the shop is performed by processing this algorithm implementing a computer. The problem in the fuzzy control is that it is very difficult to describe qualitative human knowledge in the LCR correctly. To tackle this difficulty a Fuzzy Neural Network (FNN) was introduced in this paper. The characteristics of the multi-layer FNN control system applied to the ship's steering system is investigated through the computer simulation, and the results were compared with those of the ordinary fuzzy control system of a ship. The results showed that the FNN method is a very effective to translate human knowledge into the LCR.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.47-48
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• 2015

선박교통관제사는 충돌위험이 있는 선박을 식별하기 위하여 각 선박의 벡터(코스와 속력)를 실시간으로 모니터링하며, 이때 VTS 시스템을 통하여 CPA(Closest Point of Approach)와 TCPA(Time to Closest Point of Approach)를 확인할 뿐 아니라 선박의 조우상황에 따른 위험도 함께 고려하게 된다. 본 연구는 선박충돌위험을 자선의 관점이 아닌 제 3자 즉, VTS(Vessel Traffic Service)관점에서 서로 충돌 위험이 있는 선박을 실시간으로 계산하는 알고리즘과 시스템을 개발하기 위한 기초연구로써 선박의 조우상황에 따른 위험도를 구하는 것이 목적이다.