• CDE review
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• v.3 no.3
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• pp.57-60
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• 1997

기계 부품을 설계함에 있어 솔리드 모델링 시스템의 사용을 골격으로 하는 CAD 시스템의 사용은 삼차원 모델링된 단일 물체에 대한 물성치(mass property)의 계산, FEM 해석을 위한 유한요소의 자동생성, 곡면에 대한 NC 공구경로(NC tool path)의 자동계산, 부품의 생산을 위한 가공 정보의 도출 등의 분야에 많은 도움을 주어 설계와 생산, 관리의 전 분야에 혁신적 효율화를 도모해주었다. 한편 이렇게 설계된 단품들은 대개의 경우 조립되어 조립체를 이루게 되고, 그 상태로 혹은 부품간에 상대운동을 하면서 원하는 기능을 구현하게 된다. 단품에 대해서처럼 이 과정에서도 CAD 시스템은 조립체의 삼차원 형상을 인식하고 필요한 정보를 제공해줌으로써 설계자에게 유용한 도구로 사용될 수 있는데 이를 조립체 모델링 시스템(Assembly Modeling System)이라 부르며, 현재에는 대부분의 솔리드 모델링 시스템에 그 기능이 채택되어 있다. 조립체 모델링에 관한 연구동향을 비교적 잘 정리한 문헌으로는 Turner와 Libardi의 것을 들 수 있다. 여기서는 이러한 조립체 모델링 시스템의 연구분야와 동향에 대해 또 나름으로의 시각으로 정리하였다.

• The KIPS Transactions:PartB
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• v.13B no.2 s.105
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• pp.139-148
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• 2006

In the collaborative product design environment, the communication between designers is important to capture design intents and to share a common view among the different but semantically similar terms. The Semantic Web supports integrated and uniform access to information sources and services as well as intelligent applications by the explicit representation of the semantics buried in ontology. Ontologies provide a source of shared and precisely defined terms that can be used to describe web resources and improve their accessibility to automated processes. Therefore, employing ontologies on assembly modeling makes assembly knowledge accurate and machine interpretable. In this paper, we propose a framework of semantic assembly modeling using ontologies to share design information. An assembly modeling ontology plays as a formal, explicit specification of a shared conceptualization of assembly design modeling. In this paper, implicit assembly constraints are explicitly represented using OWL (Web Ontology Language) and SWRL (Semantic Web Rule Language). The assembly ontology also captures design rationale including joint intent and spatial relationships.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.1
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• pp.48-58
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• 1989

An assembly modeling system, with which a designer can interactively create an assembly of components ready for the dynamic analysis, has been developed. In this system, an assembly model is created from the mating conditions between the components in the assembly, and then most information required for the dynamic or kinematic analysis packages are derived. For this development, the following problems have been solved; the creation of assembly data structure, the derivation of the joint information, the inference of each component's position, and the creation of the joint coordinate systems. Through this work, the designer can easily model an assembly by assigning mating conditions, and check the dynamic or kinematic performance with the automatic creation of inputs for the assembly analysis packages.

• CDE review
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• v.14 no.1
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• pp.32-37
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• 2008

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.11
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• pp.1036-1042
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• 2007

It is rather difficult to improve flight control computer(FLCC) hardware(H/W) development schedule due to lack of commercial off-the-self(COTS) tools or target specific tools. Thus, it is suggested to develop an enhanced process utilizing modeling, simulation and virtual reality tools. This paper presents H/W design process enhancement tool(PET) for FLCC design requirements such as FLCC input/output(I/O) signal flow, I/O fault detection, failure management algorithm, circuit logic, PCB assembly configuration and installation utilizing simulation and visualization in virtual space. New tool will provide simulation capability of various FLCC design configuration including shop replaceable unit(SRU) level assembly/dis-assembly utilizing open flight format 3-D modeling data.

• Journal of the Korean Geotechnical Society
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• v.24 no.1
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• pp.15-23
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• 2008

In this study, modeling shear characteristics of a coarse material mainly containing crushed stones were implemented using PFC2D, a commercially available code based on DEM(Discrete Element Method). Using the DEM code, this study provides the methodology considering the shear characteristics due to a irregular grain shape, GSD(Grain Size Distribution) and porosity of coarse material which are not effectively incorporated in conventional continuum numerical codes. Direct shear test was simulated for the GSD and porosity generated sample using the code and the simulated results showed very good agreement with the laboratory test results. The current modeling approach can be applied to other coarse materials having various GSD and porosities. Using such application, prediction of the strength characteristics of coarse material in field scale would be possible, which is limited in laboratory scale so far.

• Korean Journal of Computational Design and Engineering
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• v.10 no.2
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• pp.133-142
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• 2005

This paper proposes an object-oriented conceptual information model of mechanical assemblies, named open assembly model (OAM). The proposed assembly model primarily defines hierarchical relationships between parts and subassemblies. Together with the assembly hierarchy. the model also provides a way to represent tolerances, kinematic information, and parametric assembly constraints. Relational information such as mating conditions and degree of freedom between parts and subassemblies is captured via assembly features and relationships thereof. The information model is described using class diagrams of the Unified Modeling Language (UML), and instance diagrams are used to exemplify the proposed information model. The conceptual model presented in this paper is an integrated information model for assembly representation, which could supply necessary information for tolerance analysis and synthesis, kinematic simulation, and assembly simulation. Such a conceptual information model plays an important role for the exchange of information between modeling, analysis and planning systems. Hence, the proposed model could serve as a framework for developing data exchange standards of mechanical assemblies. The proposed model is demonstrated through a case study of a planetary gear assembly.

• Korean Journal of Computational Design and Engineering
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• v.2 no.2
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• pp.93-102
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• 1997

Most design changes are due to interferences and fit-up as parts are assembled if such a large product as an automobile or an aircraft is developed by many concurrent engineers. In this part (1) of the thesis, the assembly-centric modeling methodology with CAD systems is proposed in order to reduce the design changes. Unlike part-centric modeling method, a part is modeled with its own coordinate system which is used in downstream process as machining and measuring. The part coordinates initially have the same orientation as its assembly which is predefined in BOM (Bill of Material). Then, the corrdinates origin of the part is moved to its location to be assembled from that of its assembly coordinate system. To implement this methodology, the position data of the part w.r.t. its assembly are stored in a database to build the same hierarchical assembling structure as BOM structure. This modeling approach has the advantage of reflecting asembling sequence, because the process of positioning parts is similar to that of real assembling. And with the method, a designer can easily adjust all of the part positions of an assembly to resolve interferences if he modifies just the coordinates origin of the assembly, which results in moving included parts and assemblies together.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.3
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• pp.229-236
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• 2020

A crush switch assembly(CSA) connected to an impact fuze provides electrical signal for detonation of the loaded main charge when an impact with the target is detected. Because the CSA experiences continuous changes in flight environment such as changes in velocity, vibration, and stresses, it is necessary to accurately predict the behavior of the fuze to maintain functionality during flight and to detonate when necessary. In this paper, random vibration analysis for flight environment and impact analysis on target hit are performed using FEA. Then, high speed impact tests are performed with the original and scaled down models to ensure operation validation of the manufactured products. The test results are then compared with M&S results to verify the capability of currently modeled CSA.

• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.183-190
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• 2004

가구 제품 설계 및 디자인의 과정이 고도로 높은 기술력을 바탕으로 이루어지고 있으며, 국내의 가구 기업체도 우수한 기술력과 높은 품질로 경쟁력을 키우며 다양한 고객의 요구에 대응하여 고객만족을 꾀하여야 한다. 이의 기반이 되는 제품의 품질과 사양은 설계에서 시작되는데 아직 국내의 많은 가구기업들은 설계 및 제작 단계에서 많은 시간과 비용을 낭비하고 있다. 3D Modeling Solution은 설계오류가 적으며 시각적인 설계를 할 수 있어 최소의 인력으로 제품을 설계할 수 있는 장점이 있지만 너무 많은 기능으로 인해 사용자가 쉽게 적용하고 사용하기 어려운 단점을 가지고 있다. 본 연구에서는 Autodesk사의 Inventor와 Microsoft Visual Basic으로 Inventor에서 제공하고 있는 API함수를 이용하여 조립자동화를 위한 조립조건 생성, 조립자동화, 부품 재질변경, 수동조립 그리고 부품의 DB화를 구현하고 Add-ln 기능과 미리보기 기능을 구현하였다. 그리고 Actify사의 SpinFire Professional 프로그램을 이용해서 웹에서 모델링된 가구 부품이나 제품을 볼 수 있게 하였다.