• 제어로봇시스템학회논문지
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• 제17권9호
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• pp.892-896
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• 2011

This paper describes a camera-based position measurement system for automatic tracking control of a rubber Tired Gantry Crane (RTGC). An automatic tracking control of RTGC depends on the ability to measure its displacement and angle from a guide line that the RTGC has to follow. The measurement system proposed in this paper is composed of a camera and a PC that are mounted on the right upper between front and rear tires of the RTGC's side. The measurement accuracy of the system is affected by disturbances such as cracks and stains of the guide line, shadows, and halation from the light fluctuation. To overcome the disturbances, both side edges of the guide line are detected as two straight lines from an input image taken by the camera, and parameters of the straight lines are determined by using Hough transform. The displacement and angle of the RTGC from the guide line can be obtained from these parameters with the robustness against the disturbances. From the experiments with the disturbances, we found the accurate displacement and the angle from the guide line that have the standard deviations of 0.95 pixels and 0.22 degrees, respectively.

• 한국정보통신학회논문지
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• 제11권3호
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• pp.627-633
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• 2007

이 논문은 선적 및 하역 작업을 위해 겐추리 크레인으로 들어오는 컨테이너 트레일러의 위치 추적 시스템에 대하여 기술한다. 위치 추적 시스템은 트레일러가 겐추리 크레인에 접근하였을 때 트레일러의 정지 지점을 운전자에게 알려준다. 위치 측정 센서는 RF 신호와 초음파 방식을 채택한 크리켓 mote 모듈을 사용하였다. 실시간 전송을 위해 위치 측정 주기를 단축하였으며 삼각측량 방법에 따른 3 차원 위치 계산식과 환경적 요인에 의한 거리 측정 오류 감소 방법을 제시하였다. 측정된 위치는 블루투스 통신을 통해 주기적으로 운전자 앞의 PDA (Personal Digital Assistant)에 전송된다. 실내외 테스트 결과 위치 오류는 3 cm 이내로 개선되었으며 위치 측정 표시 주기는 평균 0.5초였다.

• 산업공학
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• 제10권2호
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• pp.69-77
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• 1997

Material handling equipment such as container cranes and transtainer cranes have made larger and faster to improve the efficiency of container handling. As conditions of use in container terminal have become severe, and also the automation level required has become higher. For the high level automation for transtainer crane, the following characteristics have to be developed 1) Container Terminal Operation & Planning System with high efficiency. 2)Autosteering System of transtainer crane with precise position sensing system using image processing and feedback control system. 3)Automatic Position Identification System with transponder. We have developed an AGSS(Automatic Gantry Steering System) of transtainer crane with image processing technology preferentially. In this paper, the system will be introduced.

• 동력기계공학회지
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• 제2권1호
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• pp.67-72
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• 1998

In crane control system, it is required that the travelling time of crane must be reduced as much as possible and there is no the swing of load at the end and starting points. In this paper, we present a hybrid control method which includes two control methods of the optimal regulator and the velocity pattern control in order to realize high performance of the anti-sway. To implement the control algorithm, the dynamic equation is linearlized at an equilibrium point, so that the linear time invariant state equation can be obtained. A 1/10 sized model crane of the usual gantry cranes is made and used to show the applicability of the developed hybrid control method. The effectiveness of developed hybrid control method is proved by experimental results which show us good performance for anti-sway control comparing to conventional velocity pattern control. Practically, it is expected that the proposed control system will make an important contribution to the automatic crane control system of the industrial fields.

• 한국전산구조공학회논문집
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• 제25권2호
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• pp.119-127
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• 2012

와이어 로프(wire rope)는 여러 가닥의 얇고 긴 철사를 감아서 밧줄과 같이 만든 것으로 굽힘과 비틀림 하중에 비해 축 하중에 더 크게 저항할 수 있는 특징을 가지고 있다. 해상 크레인, 갠트리 크레인, 크롤러 크레인 등과 같이 선박 또는 해양 구조물의 탑재를 위해 사용되는 조선용 탑재 크레인은 이러한 와이어 로프를 이용해 큰 중량의 블록들을 들거나 내리고 있다. 따라서 블록의 안전한 탑재를 위해서는 와이어 로프에 대한 동역학적 특성을 잘 파악해야 한다. 본 연구에서는 블록 탑재 시 크레인의 와이어 로프에 작용하는 장력과 비틀림 모멘트에 대한 계산식을 유도하고, 이를 기반으로 한 조선용 탑재 크레인의 동역학 시뮬레이션을 수행하였다. 그 결과, 개발된 시뮬레이션 방법이 실제 조선소의 안전한 블록 탑재 과정에 충분히 적용할 수 있음을 확인하였다.

• 한국산업융합학회 논문집
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• 제17권4호
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• pp.211-216
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• 2014

In general, gantry robot is very useful handling of heavy objects. But rope-driven yard cranes must have a little of sway and skew motion because ropes are passive mechanical device. So many researches have been concentrated on anti-sway algorithm controlling trolley speed. These approaches require sway angle. But it is very difficult to know sway angle and its derivative. Therefore control algorithm of trolley speed is not practical in general. On the contrary, control strategy using auxiliary rope is very useful to sway control of yard crane because rope length is shorter than quay-side container cranes. In this paper, we derive equations of motion of trolley system which have anti-sway controller to use auxiliary rope. And we propose the control strategy and analyse the behavior of the proposed system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.219-223
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• 2006

This paper presents a gantry type 3-axes positioning system, which is useful to test control algorithms for coordinate measuring machines and industrial cranes. The dynamic characteristics of the system have been investigated through a series of finite element analysis and experiments. In order to minimize the residual vibration during movement, this paper implements input shaping algorithms for the system with the information from the dynamic analysis. The results show that the dynamic performance of the system can be significantly improved by the dynamic analysis and implementation of input shaping

• 한국항만학회지
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• 제13권2호
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• pp.255-266
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• 1999

The purpose of this paper is to describe the design of the decision support system for container terminal ship planning and to introduce the implemented system. The ship planning in container terminals consists of three major decision processes -the working schedule of gantry cranes the discharging sequence of inbound containers the loading position and sequence of outbound containers. For making these decision the proposed system can provide two ship planning modes the interactive planning mode with user-friendly GUI and the automated planning made. To implement the automated planning routine we acquired the planning rules from the expert planner in container terminals and developed an expert system based on the rules. Finally we evaluated the system developed and the potential for commercialization by using container terminal data.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1984-1987
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• 2005

This study evaluate the statical stability of the container crane with respect to the direction of wind load which is varied between $0^{\circ}$ and $180^{\circ}$ and its average velocity is 40m/s. Using wind experimental data and a formula of wind pressure, we figured out the wind load needed to perform a finite element analysis. And we can obtain the variation of reaction forces at each supporting point according to the direction of wind load.

• 한국경영과학회지
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• 제35권2호
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• pp.1-17
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• 2010

This paper aims to compare four operating priority rules of RMGC (Rail Mounted Gantry Crane) used in semi-automated container terminal. The four priority rules employed in this paper are FCFS (First-come-first-served), LCFS (Last-come-first-served), TOS (Turn-over-served) and NFS (Nearest-first-served). And to compare the four operating priority rules, this paper analyzed productivity of RMGC and CC (Container Crane), waiting time of YT (Yard Truck) and RT (Road Truck) in container yard, and turnaround time of RT in container terminal of each priority rule by using stevedoring simulation. As a result, NFS was evaluated as the best rule to improve the overall productivity of container terminal in terms of all criteria.