• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.714-717
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• 2011

본 논문에서는 선체 블록의 운반 작업 중 발생하는 동적 하중 및 골리앗 크레인의 와이어로프와 선체블록 간의 동적 접촉력을 고려한 최적 러그 배치 시스템을 설계하고, 다물체계 동역학 커널과 외력 계산커널을 개발하였다. 다물체계 동역학 커널은 recursive formulation을 이용하여 운동 방정식을 구성하고, 외력 계산 커널은 비선형 유체정역학적 힘, 선형 유체동역학적 힘, 풍력, 계류력을 계산할 수 있다. 이를 이용해 블록에 작용하는 와이어로프와 블록 간의 간섭과 동적 접촉력을 계산하고, 그 결과를 이용하여 러그가 부착된 블록의 구조 해석을 수행하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.375-380
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• 2012

In this study, dynamic load and dynamic contact force between a building block and wire ropes of a goliath crane are calculated during lifting or turn-over of a building block for the design of an optimal lug arrangement system. In addition, a multibody dynamics kernel for implementing the system were developed. In the multibody dynamics kernel, the equations of motion are constructed using recursive formulation. To evaluate the applicability of the developed kernels, the interferences and dynamic contact force between the building block and wire ropes were calculated and then the hull structural analysis for the block was performed using the calculation result.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.213-213
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• 2004

최근 작업장에서 용접을 위해 로봇을 도입하는 사례가 많다. 단순한 장소뿐만 아니라 선체 블록 내와 같은 제약된 장소에서도 로봇을 많이 사용한다. 그렇기 때문에 로봇의 다양화와 고기능화가 더욱더 요구되고 있다. 로봇의 용접을 위한 위빙 궤적은 용접 품질과 생산성에 큰 영향을 주기 때문에 중요하다. 그러나 로봇을 도입하여 열악한 작업 환경에서 유연한 동작을 적용하기에는 말은 시행착오와 비용이 소요된다. 그래서 용접 로봇의 도입 이전 단계에서 위빙 궤적이 작업 환경에 맞게 로봇에 적용되는지 확인하는 것이 필요하다.(중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.39-44
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• 2006

현재 조선산업은 선박의 대형화 추세에 맞추어 선체블록 규모가 대형화되고 있다. 따라서 대형 선체블록제작을 위한 블록전문업체가 증가하고 있으며, 그에 따른 블록조립 및 정도계측기술 개발이 절실히 요구되고 있다. 이에 본 연구에서는 그간 수행해온 블록계측과 관련된 각종 데이터베이스를 구축하고, 시스템 기능구현에 핵심 기술인 소프트웨어 개발 기법, 정보 가시화 기법을 제시하고 이를 이용한 인터페이스를 개발하여 본 시스템의 구성요소를 유기적으로 연결하여 사용하는 과정을 시연함으로써 블록조립 정도평가 시스템의 유용성과 기능을 검증하였다.

• Journal of IKEEE
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• v.25 no.1
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• pp.95-100
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• 2021

If we know the location of the hull block and the welding feeder in the shipyard, we can easily obtain the location information of the worker. That data is very useful for implementing a workplace safety monitoring system. However, it is difficult to apply a fixed communication network to the workplace due to the specificity of the hull structure and welding process. In this study, inductive power line communication, which can replace dedicated communication line, was reviewed. A ferrite core was used as an inductive coupler to be installed on the power cable of the welding machine, and a nano-crystalline core was applied as a coupler to be fastened to the support rod of the metal block. In order to visualize the operating principle of the proposed couplers, 3D modeling and finite element analysis were performed with the COMSOL AC/DC module. In the communication performance test using an aluminum profile, when the communication channel was formed by the contact of the welding electrode, the bandwidth was kept above 6 Mbps.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.2
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• pp.98-105
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• 2004

This study focuses on an analytical approach to calculate four crane lifting forces for heavy ship hull blocks considering elongations of lilting slings. Four-crane-lifting is a redundant problem. During lifting procedures, in addition to the force and moment equilibrium equations, a compatibility condition is introduced to determine 4 unknown lifting forces. For verification of the method, a ship hull block with field measurements data is analyzed and the result shows that the information obtained by current method could be useful to engineers to conduct lifting work at shipyards.

• Proceedings of the KWS Conference
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• 1999.10a
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• pp.87-90
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• 1999

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.164-165
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• 2000

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4717-4722
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• 2014

In shipyards, a large number of dog-pieces are used to align welding joints and prevent welding deformation in the block assembly stage. The huge working man-hours consumed in the working process of dog-pieces impedes the productivity growth of shipyards. In this study, an analysis method based on the experimental results was proposed to simulate the welding deformation of butt joints with a dog-piece setting. The simulation of welding deformation of a hull block joint was performed using the proposed analysis method. Finally, the proposed analysis method can be used to establish guidelines for the proper use of dog- pieces in the block assembly stage.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.2
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• pp.127-136
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• 2000

Welding deformations reduce the accuracy of ship hull blocks and decrease the productivity due to correction work. Preparing an error-minimizing guide at the design stage will lead to a high quality as well as high productivity. And a precise method to predict the weld deformation is an essential part of it. This paper proposes an efficient method to predict complicated weld deformations based on the inherent strain theory combined with the finite element method. The inherent strain is determined by the highest temperature and the degree of restraint. In order to calculate the inherent strain exactly, it is considered that the degree of restraint becomes different according to the fabrication stages in real structures. A simulation of a stiffened plate shows the applicability of this method to simple ship hull blocks.