• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.293-296
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• 1999

In conventional automatic container-terminal, the gantry cranes are operated manually or semi-automatically. But UGC is an unmanned-operated gantry crane and the positioning information for UGC is supplied only by position-measuring devices. In order to enhance the operation efficiency of UGC, it is required that the position-measuring devices have long maintenance period and are not sensitive to the weather and environment condition. And in order to be used practically in container terminal, the cost of position-measuring devices is not higher than currently used measuring devices. In the study, it is discussed the requirements for position-measuring devices in UGC, And it is studied on the measuring devices suitable to UGC. From this study, it is expected that the combination of a rotary encoder and a ferrous metal detector is useful for position-measuring devices in UGC.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.4
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• pp.880-888
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• 2001

This paper presents a fault detection asnd isolation algorithm for highly reliable gantry crane system. The algorithm is constructed by multiple PI observer technique, and the magnitude of actuator fault can be estimated by using integrated estimated output error. Also, the complex actuator and /or sensor fault can be detected and isolated by monitoring the integrated error and the estimated state error. Considering the actuator and/or the sensor fault, we verify that these fault can be detected and isolated through simulation. Lastly, we show a simple reliable control method by using the detected fault signal and an added observer.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.387-392
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• 2004

The control objectives in this paper are to move the gantry of a container crane to its target position and to suppress the transverse vibration of the payload. The crane system is modeled as an axially moving string equation, in which control inputs are applied at both ends, through the gantry and the payload. The dynamics of the moving string are derived using Hamilton's principle for systems with changing mass. The Lyapunov function method is used in deriving a boundary control law, in which the Lyapunov function candidate is introduced from the total mechanical energy of the system. The performance of the proposed control law is compared with other two control algorithms available in the literature. Experimental results are given.

• Journal of Navigation and Port Research
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• v.34 no.6
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• pp.479-485
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• 2010

To handle container effectively is one of the most important factors in a port because working time is linked soon into cost. Since the middle of 1990s, RMGC(Rail-Mounted Gantry Crane) and RTGC(Rubber-Tired Gantry Crane) have been developed and widely used to operate containers in the yard. The RTGC is more difficult than RMGC in the automatic control system design. Although, the RTGC is largely advantaged to free driving environment, it has some considerable disadvantages in the system operating. In general, the problems are due to tire slip and lack of tire pressure etc. Therefore, a desirable research result has not been shown in this time. So, in this paper, we propose a new approach to design tracking control system for the RTGC in which the mathematical modeling is included. From the simulation results, the control performance of the designed control systems is evaluated.

• Wind and Structures
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• v.19 no.1
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• pp.1-14
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• 2014

Rail-mounted cranes can be easily damaged by a sudden gust of wind while working at a running speed, due to the large mass and high barycenter positions. In current designs, working rail-mounted cranes mainly depend on wheel braking torques to resist large wind load. Regular brakes, however, cannot satisfactorily stop the crane, which induces safety issues of cranes and hence leads to frequent crane accidents, especially in sudden gusts of wind. Therefore, it is necessary and important to study the braking performance of working rail mounted cranes under wind load. In this study, a simplified mechanical model was built to simulate the working rail mounted gantry crane, and dynamic analysis of the model was carried out to deduce braking performance equations that reflect the qualitative relations among braking time, braking distance, wind load, and braking torque. It was shown that, under constant braking torque, there existed inflection points on the curves of braking time and distance versus windforce. Both the braking time and the distance increased sharply when wind load exceeded the inflection point value, referred to as the threshold windforce. The braking performance of a 300 ton shipbuilding gantry crane was modeled and analyzed using multibody dynamics software ADAMS. The simulation results were fitted by quadratic curves to show the changes of braking time and distance versus windforce under various mount of braking torques. The threshold windforce could be obtained theoretically by taking derivative of fitted curves. Based on the fitted functional relationship between threshold windforce and braking torque, theoretical basis are provided to ensure a safe and rational design for crane wind-resistant braking systems.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.465-470
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• 2004

In this paper, an open architecture control system for automatic container cranes is investigated. A standard reference model for cranes, which consists of three modules； hardware module, operating system module, and application software module, is proposed. A hybrid control architecture combining deliberative and reactive controls for the autonomous operation of the cranes is proposed. The main contributions of this paper are as follows： First, a new reference platform for the crane control system is proposed. Second, by analyzing the structure of a container crane, implementation strategies for the automatic container crane are described.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.166.4-166
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• 2001

The oscillation of a crane system is divided into the oscillation of container in respect of its trolley and the oscillation of trolley in relation to the whole crane system. We introduce a new type of crane system that avoids to the irreducible sway of crane system caused by hanging cables. The cables suspending the spreader are replaced by using an "anti-sway system". The proposed system is composed of mechanical arms with function of anti-sway based on conventional line system. The effectiveness of the proposed new type crane system and the controller is shown through the simulation results.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.9
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• pp.88-95
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• 2009

Input shaping has been a very effective control method for reducing payload swing in industrial bridge and gantry cranes. However, conventional input shapers often degrade performance when applied to tower cranes because of the nonlinear coupled dynamics between rotational and radial motions in tower cranes. To alleviate this problem, a new input shaper for tower cranes is developed by means of dynamic modeling, analysis and optimization. This work investigates the tower crane dynamics along with parameters of the tower crane varied. A performance index for input shaper design is proposed so as to reduce the coupled residual vibration of a tower crane using only rotational motion of tower crane. The proposed new input shaper is verified to be effective through simulations and experiments.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.04a
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• pp.280-281
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• 2010

컨테이너의 효율적인 이송은 작업 시간이 곧 비용으로 연결되는 항만에서 가장 중요한 요소이다. 따라서 1990년대 중반부터 세계항만은 RMGC(Rail-Mounted Gantry Crane), RTGC(Rubber-Tired Gantry Crane)등의 크레인이 개발되어 야드에서 컨테이너를 적재하는데 널리 이용되어 오고 있으며, 특히 최근에는 CCD카메라, 각종 센서 둥을 이용하여 트랜스퍼 크레인의 무인화를 위해 수많은 연구가 진행되었고 실용화 된 많은 기술들이 현장에서 사용되고 있으나, 여전히 많은 부분이 연구를 필요로 한다. 특히 RTGC의 경우 RMGC에 비해 무인 자동화 연구개발은 미비한 수준이다. 따라서 본 논문에서 RTGC의 무인자동화 작업을 위한 가장 기초라고 볼 수 있는 수학적 모델링을 기반으로한 고정밀도 주행제어기를 설계하고자 한다.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.307-307
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• 2000

The swing motion of the spreader during and after movement causes an efficiency problem of position control in unmaned gantry crane. The objective of this research is to design implementable stabilizing controllers that minimize the swing motion of spreader in precise position control. The dynamic equations related to trolley, rope, and spreader are derived. For constitute a similar actual system, we introduced a conception of spring and damper in the connector. It is located between the trolley and link that is used in stead of rope. We derived dynamic equation by appliance that friction and external disturbance are occurred to the connector. We constituted of position servo system and velocity servo system for the control of position and velocity of the trolley and constituted of lag compensator system for the control of sway of the spreader. And we will show an effect of the proposed system in this research finally.