• 대한조선학회논문집
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• 제58권6호
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• pp.358-365
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• 2021

Crabbing motion is a pure sway motion with only sway velocity. The ship's crabbing motion is essential for an ideal berthing/unberthing process. The unberthing situation proceeds in sequential order such as crabbing motion section, pivoting section, and outer port section. For the berthing situation, the sequence has a reverse order: the inner port section, pivoting section, and crabbing motion section. In this paper, the berthing/unberthing data of the reference ship, Pukyong National University research ship "NARA", was analyzed to develop a sway velocity reference model. Several constraints were defined to derive the crabbing motion section during berthing/unberthing. The sway velocity reference model for the auto-berthing/unberthing was developed using the estimated sway velocity. A reproduction simulation of the ship was performed to compare the designed reference model and the reference ship data.

• 대한조선학회논문집
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• 제60권3호
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• pp.165-174
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• 2023

Unmanned Surface Vehicle (USV)'s berthing and unberthing is the most difficult maneuvering tasks and have the highest risk of accidents. In this paper, we designed a berthing/unberthing control algorithm given human joystick command for an USV equipped with a waterjet and a bow thruster. The berthing and unberthing maneuvers are performed remotely by a joystick operator at the Ground Control Center (GCC) where the status of USV and environmental situation can be monitored. We interpret the human joystick commands into USV's desired speed, yaw rate, and heading angle commands. next, we developed a control algorithm for the desired target values of MIMO actuators (engine speed, bucket step, nozzle angle, and bow thruster state) to follow the interpreted commands. The validity of the control algorithm is confirmed through simulations and sea trials at Gwang Am port.

• 한국항해항만학회지
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• 제33권1호
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• pp.21-25
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• 2009

선박이 부두에 이접안할 경우 쓰러스터나 특수 추진기가 없는 선박은 예선의 도움을 받아 이접안을 하게 된다. 이접안시 예선들은 도선사의 명령에 의하여 선박의 이접안을 도와주게 된다. 이때 본선과 예선의 위치가 2차원 지도에 표시되고 부두와의 상대적인 거리가 나타난다면 이접안에 매우 도움이 될 것으로 생각된다. 본 연구에서는 이러한 예선사용 지윈 시스템에 대해서 개념 설계를 수행하였다. 예선사용 지원 시스템은 본선, 예선 및 부두의 상황을 모니터링하는 예선사용 모니터링 기능과 해양환경을 고려하여 필요한 예선력을 계산하여 나타내주는 예선사용 자동화 기능을 갖고 있다. 이러한 예선사용 지원 시스템은 항만에 설치된 네트워크를 기반으로 설계되었으며, 추후 한국해양연구원의 선박운항 시뮬레이터를 이용하여 검증될 계획이다.

• 한국항해항만학회지
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• 제31권5호
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• pp.325-332
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• 2007

본 연구에서는 조이스틱을 이용하여 프로펠러와 타, 선수/선미 쓰러스터를 갖는 선박의 접이안을 위한 제어 알고리즘을 개발하였다. 조이스틱으로부터 전진 방향 및 회전 방향의 속도명령을 받아 전진 방향 및 회전 방향의 속도를 제어하는 MIMO(Multi-Input Multi-Output) 비선형 제어 알고리즘을 개발하기 위해 저속 조종수학모형을 사용하였다. 또한, 본 연구에서는 비선형 및 PID 제어기의 성능을 검증하기 위해 선박 접이안 가상 HILS(Hardware in the Loop Simulation) 프로그램을 구현하였다. HILS 프로그램은 LabWindow/CVI를 이용하여 개발하였으며, 사용자는 선박의 현재 위치와 원하는 궤적을 모니터를 통해 본 후 조이스틱을 이용하여 선박의 전진 방향 및 회전방향 속도를 제어함으로서 선박을 조종한다. 시뮬레이션 결과를 보면 비선형 제어기와 PID 제어기는 개루프 조이스틱 제어기보다 타와 쓰러스터의 입력 크기뿐 아니라 선박의 위치오차 면에서도 우수한 성능을 보였다.

• 한국항해항만학회지
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• 제36권7호
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• pp.571-575
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• 2012

Berthing and unberthing maneuver is essential work for marine pilots and securing the safety against risks during the maneuver is more important than anything else. Moreover, the maneuvering environment in ports and harbors has changed rapidly and got worse due to development of a new port, the advent of a new type or large-sized ship, and the rapid increase in harbor traffic. As one of measures taken to cope with such changes in the maneuvering environment and for each pilot to improve his own maneuvering ability, this paper developed laptop-based ship-handling simulator which is readily available anytime and anywhere. This paper is to develop a conning display for ship's maneuvering and electronic chart based display widely used nowadays to represent a model ship's movement. The displays were arranged appropriately considering pilot age, easy handling by mouse, using a maximum screen, proper arrangement of rudder, engine, thruster, tug etc and representation of information. Up to now thirteen (13) model ships were developed based on real-ship, whose mathematical model is Japanese MMG & pilots' low speed maneuver.

• 한국항해항만학회지
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• 제44권6호
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• pp.439-446
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• 2020

세계적인 환경오염 규제 및 IMO(국제해사기구)의 선박 연료 황 함유량 제한으로 LNG를 선박의 연료로 사용하는 연구 및 사업이 활발히 진행되고 있다. 본 연구에서는 기존 연구를 통해 개발된 부유식 LNG 벙커링 터미널(FLBT, Floating LNG bunkering terminal)을 대상으로, STS LNG 벙커링 작업을 위해 이접안 하는 과정을 벙커링 셔틀선의 환경하중을 모형시험과 수치해석으로 평가하였다. 고차경계요소법을 이용한 수치해석으로 가까운 위치에서 상호작용 하는 4척 선박들의 파랑표류력 변화를 검토하였다. 다양한 이접안 거리에 따라 파랑표류력이 크게 변함을 확인 했다. 모형시험은 선박해양플랜트연구소의 해양공학수조에서 이루어졌다. 모형시험에서는 예인선을 모사하여 대상선박을 밀고 당길 수 있는 치구를 고안하였으며 접안시 마찰력 등의 영향 없이 선박을 밀 수 있도록 하였다. 모형시험 결과 LNG벙커링 선박은 대부분의 1년 환경조건에서 안전한 이접안이 가능하였다. 파랑 방향에 따라 안정성의 차이가 존재함으로, FLBT의 Heading conrol 기능을 적용하여 횡파를 피한다면 더욱 안정적인 운용이 가능할 것이다.

• 한국항해항만학회지
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• 제38권6호
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• pp.689-694
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• 2014

The Korean government has introduced and enforced maritime traffic safety assessment to secure traffic safety since 2010. The maritime traffic safety assessment is needed by law to design a new port or modify an existing one. According to Korea Maritime Safety Act, in the assessment the propriety of marine traffic system consists of the safety of channel transit and berthing/unberthing maneuver, safety of mooring, and safety of marine traffic flow. The safety of channel transit and berthing/unberthing maneuver can be evaluated only by ship-handling simulation. The ship-handling simulation is carried out by sea pilots working with the port concerned. The vessel's proximity measure is an important factor to evaluate traffic safety. The proximity measure is composed of vessel's closest distance to channel boundary and probability of grounding/collision. What is more, the probability of grounding becomes important. According to central limit theorem, a sample has a normal distribution on condition that its size is more than 30. However, more than 30 simulation runs bring about the increase of assessment period and difficulty of employing sea pilots. Therefore this paper is to find out minimum sample size for evaluating vessel's proximity. First sample sets of size of 3, 5, 7, 9 etc. are selected randomly on the basis of normal distribution. And then KS test for goodness of fit and t-test for confidence interval are applied to each sample set. Finally this paper decides the minimum sample size. As a result this paper suggests the minimum sample size of 5, that is, the simulation of more than five times.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1991년도 하계학술발표회 한국항해학회
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• pp.45-48
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• 1991

This work aims to introduce the concept of microcomputer aided port design simulation methodology including the analysis of the mathematical models to be implemented and apply it to the Third Stage Busan Part Development Project. In the Busan case study the size of the proposed turning basin of the new terminal together with the operational stra-tegies of berthing and unberthing was examined In addition the safety of ships' entry and exit through the projection new breakwaters was as-certained. From the application of simulation to the Busan project it was found that the proposed dredging area was not sufficiently wide enough for a modelled container ship to perform A type unberthing (in which the ship turns to port as she monoeuvres away from No.1 berth with the ass-istance of tuges) especially in a strong easterly wind., It is therefore recommended that Busan pilots should be advised to use B type unberthing strategy in which the ship goes astern from No.1 berth to the turning area in front of No.2 berth(where the ship turns 180 degrees clockwise) especially when the wind is very strong. It is also recommended that a sea buoy be placed outside the new breakwaters as this was found to im-prove the safety of ship manoeuvres through the breakwaters significant-ly. Another recommendation is that the Korean Hydrodynamic Office carry out a detailed survey of the currents in the water area near the new breakwaters. once they have been constructed. In addition it is to be recommended that a current meter be placed at the recommended sea buoy pardised by erroneous current information

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 춘계학술대회
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• pp.255-257
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• 2014

항내 정온도는 항만의 박지(泊地) 내 수면의 정온한 정도를 나타내는 것으로서, 선박의 접이안, 하역작업과 관계가 있지만 이보다 안전한 피항지로서의 최소한의 수역을 파악하기 위한 중요한 지표이다. 따라서, 항내 정온도 예측시 항외로부터 입사하는 파랑의 굴절, 회절, 천수 및 반사 등에 의한 항내파고 및 파향의 변화를 복합적으로 해석해야 한다. 그러나 항내 정온도 검토를 위하여 현재 운용 중인 수치모형실험은 각각의 특성에 따른 결과의 상이함에 따라 이에 대한 기본적인 재검토가 필요한 것으로 판단되며, 이에 본 연구에서는 후포항을 대상으로 수치모형실험결과와 비교함으로써 현재 운용 중인 모형의 타당성을 검토하였다.

• 수산해양교육연구
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• 제23권2호
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• pp.210-220
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• 2011

The Keyongin Inland waterway will connect with Han-River and the Northen part of the Incheon-seaway and this way will be opened at the early of October this year. In this regard, the Incheon container terminal is under constructing for 1,000 TEU & 550 TEU container vessels at the place of leftside of the Seohae lockgate. However the terminal length is not still fixed due to at a great expenses of construction and dosposal matter of the dredged soil. So this paper will suggest the optimum berth length by using the full mission shiphandling simulator for berthing and unberthing shipmaneuvering. And also evaluates the design standard of harbor construction rules and analysis optimum berth length against ship's length for safe shiphandling at terminals in accordance with the customary practices of the major ports in Korea.