• Journal of Ship and Ocean Technology
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• 제8권2호
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• pp.1-12
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• 2004

To keep the ocean environment from pollutions, strict international requirements on the controllability are arisen to the VLCC. Especially in low speed operations near the harbor, the VLCC is often supported by tug to replenish the insufficient rudder force. When water jet is blown to the flapped rudder, the Coanda effect induces a high-lift force by delaying stall and re-enforcing circulation in a large angle of attack (Lachmann 1961, Ahn 2003). Based on numerous research efforts, the rudder system supported by the Coanda effect was devised and its performances were evaluated in the towing tank for a large VLCC model. Hydrodynamic forces acting on the rudder system were measured with a water jet blowing on the rudder surface and compared with those acting on a conventional rudder. The effectiveness of the new rudder system was proven through an experimental evaluation.

• 한국항해항만학회지
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• 제29권10호
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• pp.839-845
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• 2005

조타에 의해 불규칙파 중 선박의 선수동요 및 횡요를 제어하는 횡요 감소시스템에 관한 연구를 수행하였다. 횡요를 포함한 선박 운동 시뮬레이션을 위해 4-자유도 조종 운동방정식을 사용하였고, 선체에 가해지는 외력으로서 파강제력이 고려되었다. 파강제력은 3차원 특이점 분포법에서 얻어진 주파수 전달함수로부터 시간영역해석법을 적용하였다. 선수동요와 횡요를 제어하는 PD 제어기를 각각 구성하고, 이를 선형 결합하여 횡요 감소 조타 제어기를 구성하였다. 조타 속도 및 타의 종류를 변화시켜 선수동요 및 횡요의 제어효율을 검토하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.55-61
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• 2005

조타에 의해 불규칙파$\cdot$중 선박의 선수동요 및 횡요를 제어하는 횡요 감소시스템에 관한 연구를 수행하였다. 횡요를 포함한 선박 운동 시뮬레이션을 위해 4-자유도 조종 운동방정식을 사용하였고, 선체에 가해지는 외력으로서 파강제력이 고려되었다. 파강제력은 3차원 특이점 분포법에서 얻어진 주파수 전달함수로부터 시간영역해석법을 적용하였다. 선수동요와 횡요를 제어하는 PD 제어기를 각각 구성하고, 이를 선형 결합하여 횡요 감소 조타 제어기를 구성하였다. 조타 속도 및 타의 종류를 변화시켜 선수동요 및 횡요의 제어효율을 검토하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1647-1650
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• 1997

This paper presents the control law of Automatic Rudder Trim System(ARTS) for the KTX-1. The proposed ARTS is designed mainly t reduce the pilot's work load for trimming in the various conditiions of engine torque. airspeed, and aircraft configuration. The ARTS partially compensates the transient yawing motion due to change of engine power in turboprop aircraft because of the limitation of the actuation speed of the trim motor. In this paper flight test data are analyzed to understand the phenomena and the dynamics of the reversible rudder flight control system is derived. Finally, the control concept and conrtol law of ARTS are described and the characteristics of the ARTS are analyzed through simulation study.

• 한국항해항만학회지
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• 제31권4호
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• pp.289-293
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• 2007

In this paper, new application of adaptive neural network to design a ship's Rudder-Roll Damping(RRD) control system is presented Firstly, the ANNAI neural network controller is presented. Secondly, new RRD control system using this neural network approach is developed. It uses two neural network controllers for heading control and roll damping control separately. Finally, Computer simulation of this RRD control system is carried out to compare with a linear quadratic optimal RRD control system; discussions and conclusions are provided. The simulation results show the feasibility of using ANNAI controller for RRD. Also, the necessity of mathematical ship model in designing RRD control system is removed by using NN control technique.

• Journal of Advanced Marine Engineering and Technology
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• 제39권5호
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• pp.577-585
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• 2015

This paper deals with development of an autopilot system for leisure yacht based on NMEA 2000 network and android platform. The developed system can operate both for manual steering and automatic navigation mode. In automatic steering mode, after manipulation of commands which are NMEA 0183 sentences by android platform, the developed system translates and sends the packets through NMEA 2000 network. Then the controller which is connected to NMEA 2000 network receives the commands and controls the boat's rudder system automatically. The automatic steering mode is achieved by cooperation of two controllers; one for controlling the rudder system, and the other for controlling the vessel's heading. To control the vessel's rudder and heading angle two PID controllers are developed with an adjustable dead-band gain. Also, in order to eliminate the steady-state error occurred by applying dead-band, an integral controller which specifically supervises the system's behavior inside the dead-band area is developed. In this paper, at the first stage, simulations are accomplished using computer in order to examine the feasibility of the proposed based on simulation results. In the next step, the system on a real hydraulic steering model is implemented and at the end the performance examination by implementing it on a real boat and doing test navigation is executed.

• 한국군사과학기술학회지
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• 제2권1호
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• pp.121-131
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• 1999

프로펠러 항공기에서는 추력효과 때문에 엔진 출력 변동시 트림 상태를 유지하기 위해서 계속적인 트림 스위치 조작을 하여야 한다. 자동러더트림장치는 고출력 터보 프롭 항공기에서 추력효과가 발생할 때 트림 상태를 유지하기 위해 러더 트림 조작에 필요한 조종사의 조종부담을 경감시키기 위해 도입된 장치이다. 본 논문은 자동러더트림장치 개발을 위한 기술적인 해석, 제어법칙에 대한 설계, 그리고 장치 적용에 따른 비행운동에 있어서의 효과를 분석한 내용이다. 자동러더트림장치의 제어 법칙은 항공기 특성 분석과 설계 요구도 및 제약 조건 등을 고려하여 설계되었고, 트림 맵을 이용하는 개루프제어 방법과 횡축 가속도를 제환 신호로 사용하여 개루프 시스템의 에러를 보상하도록 하는 폐루프 제어 방법의 통합으로 구현되었다. 설계된 제어 법칙을 이용한 자동러더트림장치를 실제 항공기에 장착하여 시험한 결과 방향축 트림을 위한 조종사의 조종부담을 효과적으로 감소시켰고, 엔진 출력이 변할 때 발생하는 순간 요우 모션도 크게 보상시킴을 확인하였다.

• 대한조선학회논문집
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• 제47권2호
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• pp.122-131
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• 2010

The increasing size and speed of cargo ships result in high speed flow in propeller slipstream, and thereby cavitation is frequently observed on and around a rudder system. Rudder gap cavitation is the most difficult one to control and suppress among various types of the cavitation on a rudder system. In the present study, experiments of the incipient cavitation and pressure measurement were carried out for typical cargo ship rudder sections with and without the suppression devices, which were suggested by the authors. Fundamental understanding of the rudder gap cavitation inception was obtained along with its relevance to the surface pressure distribution. It is confirmed that the gap flow blocking devices effectively suppress the rudder gap cavitation and, at the same time, augment lift.

• 한국항공우주학회지
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• 제30권2호
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• pp.115-121
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• 2002

본 논문은 KTX-1 기본훈련기 방향타 조종계통의 정적 하중 시험을 요약한 것이다. 방향타 콘트롤 시스템 정적 하중시험은 정하중 구조 시험용 KTX-1 #004호기에 장착 상태에서 실시하였으며 사용되는 모든 부품은 실제와 동일한 것으로 장착하고 정적하중 시험을 실시하였다. 시험하중 조건은 설계 제한하중(Design Limit Load)과 설계 극한하중(Design Ultimate Load)까지 시험을 수행하며, 전방석과 후방석 패달에 동시하중을 작용하는 경우 중복하중계수(Dual Factor)까지 고려하였다. 이 시험의 요구하중은 MIL-A-8855(USAF)의 요구조건에 따라 수행하였으며, 방향타 콘트롤 시스템 시험 결과는 미 군사규격 요구조건을 만족하였다.

• 전기학회논문지
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• 제66권8호
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• pp.1285-1290
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• 2017

In this paper, we developed a core module of the steering system to control and operate the outboard ship with the automatic steering system, and implemented it as a complete integrated system. In particular, this paper presents the problem of the rudder sensor used in the existing system and implements the contactless rudder sensor as an improvement. In the case of existing rudder sensors, there is a problem that safety operation and economic loss of the ship operation is caused by malfunction due to immersion during use in outboard vessels. However, the proposed rudder sensor is separated from the rotary shaft to constitute a contactless type, and a circular magnet is fixed so that the rotating value can be detected and used by the Hall sensor to completely solve the flooding problem. As a result of the characteristic test, the voltage value from 1.8V to 3.2V was obtained between $-35^{\circ}$ and $+35^{\circ}$ degrees and satisfied the reference value. The proposed rudder sensor was mounted on the outboard ship, and all the performance of controller system were checked. According to the system proposed in this paper, it satisfies the Korean Standard Specification, which defines the speed of convergence in 30 seconds by switching from left to right in 7 seconds. We also confirmed that automatic steering was performed by comparing the compass sensor with the destination in the integrated controller at the start-up.