• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.5
• /
• pp.693-705
• /
• 2013

Procedural models have the advantage of being easy to edit simply by changing the values of the parameters of their constructional operations. In previous studies, we have introduced an approach for representing procedural 2D CAD models in ISO 10303 and developed ISO 10303-112 for the exchange of procedural 2D CAD models. In this paper, a method for the development of a procedural 2D CAD data translator supporting ISO 10303-112 is suggested. Furthermore, the core techniques applied to the translator are presented. The feasibility of the proposed method was demonstrated through data exchange experiments using a prototype translator.

• Korean Journal of Computational Design and Engineering
• /
• v.10 no.3
• /
• pp.179-187
• /
• 2005

The usage of mixed 2D and 3D CAD data of commercial CAD systems is required in the construction practice. Sometimes 3D wireframe model is required by end-users when 2D CAD data is delivered. However, current KOSDIC can not represent 3D CAD data, because it has been developed as a 2D drawing delivery standard. Therefore, this study is to provide exchange and sharing of mixed 2D and 3D CAD data that add 3D wireframe model in the KOSDIC. To achieve this purpose, the authors have investigated the 3D CAD entities of commercial CAD systems, and have analyzed STEP standards providing 3D wireframe model. The result, the authors have extracted 3D CAD common entities based wireframe model which shall be added in the KOSDIC. This study can be beneficial by using the developed data model for heterogeneous CAD systems, and by providing the representation of mixed 2D and 3D CAD data in construction practice such as GIS, piping system, and so forth.

• Journal of Korea Multimedia Society
• /
• v.9 no.8
• /
• pp.1010-1019
• /
• 2006

CAD system is a very important technology in designing the products which we are using today. This CAD technology has been enlarging its area into 3D CAD systems with the development of computer graphics technologies. In particular, such advances have been realized in special area such as the CAD system for designing shoes. However, because it is difficult to design a 3D CAD system, most CAD developments except for major CAD software companies usually have employed the AutoCAD which realizes 3D concepts. Also, many shoes' designers have been skilled with 2D shoe CAD systems and then they can make high achievements. Therefore, we design a new shoe CAD system with advantages of 2D CAD system and 3D CAD system. We also implement the scheme to transfer the data between 2D CAD system and 3D CAD system and also grading technologies to get patterns of various shoes size from a basic shoe's design.

• Korean Journal of Computational Design and Engineering
• /
• v.10 no.1
• /
• pp.11-16
• /
• 2005

CAD/CAM system may have such advantages of cost reduction, production time shortening, and product quality improvement. But current advanced versions of CAD/CAM system for 3-D NC data generation are too much expensive to purchase and too difficult to make full use for small-scale manufacturers whose main products are of 2-D simple shapes. The objective of this paper is to introduce a cost-effective way to 2-D NC data generation with a widely spread CAD software. Using VISUAL LISP in the well-known AUTO-CAD, the contents and steps of an automatic NC data generation program are presented for 2-D machining of contours and pockets. To approve the usefulness of program, a test application to a real part is exhibited also.

• Korean Journal of Computational Design and Engineering
• /
• v.11 no.6
• /
• pp.447-454
• /
• 2006

Although there are many needs to use 3D models in MEMS field, it is not easy to generate 3D models based on MEMS CAD. This is because MEMS CAD is based on 2D and their popular format-GDSII file format- has its own limits and problems. The differences between GDSII file format and 3D CAD system, such as (1) superposed modeling, (2) duplicated entity, (3) restricted of entity type, give rise to several problems in data exchange. These limits and problems in GDSII file format have prevented 3D CAD system from generating 3D models from the MEMS CAD. To remove these limits and solve problems, it is important to extract the silhouette of data in the MEMS CAD. The proposed method has two main processes to extract silhouette; one is to extract the pseudo-silhouette from the original 2D MEMS data and the other is to remove useless objects to complete the silhouette. The paper reports on the experience gained in data exchange between 2D MEMS data and 3D models by the proposed method and a case study is presented, which employs the proposed method using MEMS CAD IntelliMask and Solidworks.

• Journal of Game and Entertainment
• /
• v.2 no.1
• /
• pp.64-70
• /
• 2006

CAD system is a very important technology in designing many products which we are using today. This CAD technology have enlarging its area into 3D CAD systems with the development of computer graphics technologies. In particular, such advances have also been realized in special area such as the CAD system for designing shoes. 3D CAD systems for shoes design must provide compatibility between 3D and 2D data because shoes are made using 2D parts of pieces of leather or cloth. Many designers get high performances using 2D shoe CAD systems because they have had long practices with the 2D systems. Therefore, to get the mapping between 2D modeling and 3D modeling is one of very important components in 3D CAD system. In this paper, we proposed a flattening method that convert 3D shoes data to 2D data.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.22 no.5
• /
• pp.475-485
• /
• 2009

In this paper a two-step algorithm is proposed to efficiently generate rebar elements from 3D CAD data in the context of CAD/CAE data transfer. The first step is an algorithm to identify various type rebar objects and their attributes by analyzing 3D CAD data in STEP format, which is one of the international data standards. The second algorithmic step is a procedure to generate one-dimensional rebar elements from the object data made through the first step for finite element analysis or other CAE tasks. Successful rebar element data generation from real 3D CAD data for a reinforced concrete structure shows the efficacy of the proposed algorithm.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.9
• /
• pp.25-34
• /
• 1999

In spite of the advance of 3D solid modeling technology, there are some distinct areas where 2D CAD S/W are still dominant, and more competent comparing with 3D CAD S/W. For example, in the manufacturing of 2D-shaped electrical parts, most related manufacturing tools have 2D geometric features by nature, and 3D solid models applied to these parts have substantial overheads. Nevertheless, most 2D CAD S/W have no topological inquiry services because they have no such information on their geometrical database inherently. Thus, it is needed to extract such information from 2D CAD database for developing more advanced application such as automated drafting/design S/W. In this paper, the extraction of topological information from 2D CAD has been performed in general way using concept of B-rep. A general extraction algorithm, data structure and meta file format for 2D topological object have been developed and successfully applied to the development of the automated lead frame die design system in Samsung Aerospace. it is also possible to provide a flexible, powerful topology-oriented functionality on any common 2D CAD S/W.

• Journal of Fashion Business
• /
• v.21 no.6
• /
• pp.87-105
• /
• 2017

In the fashion industry, 2D apparel CAD technology has already matured and various 3D apparel CADs have been introduced and are available for users. In the fourth industrial revolution era, the 3D apparel technology will be highlighted, and the research of 3D apparel CAD will be much more emphasized upon. Currently, various 3D apparel CAD have been developed and commercialized due to the rapid development of technology. However, in reality, the analysis and discussions about its problems and the improvements for clothing from a user's perspective have not been carried out yet. The purpose of this study was to provide the reference information about 3D apparel CAD for users by studying and comparing the characteristics of 3D apparel CAD. The 3D apparel CAD, DC Suite and CLO3D were selected for technical comparative study. The 3D apparel CAD mainly includes 3D body system, garment pattern system and garment simulation system and so on. It was compared and analyzed; the problem was presented, and the directions of improvement were put forth.

• Journal of the Society of Naval Architects of Korea
• /
• v.35 no.4
• /
• pp.98-108
• /
• 1998

Hull design data is currently prepared by a 2D CAD system and re-input to 3D CAD systems specialized for detail design or to a structural analysis system. In this paper, sharing design data among different CAD systems has been studied. Based on STEP methodology, a neutral model is generated from 2D AutoCAD drawings. To handle a geometric data of this model, the non-manifold model of ACIS is used because it can support various CAD data representation such as 2D graphic entities, 3D wireframe, 3D surface model, and solid B-Rep/CSG model. It is observed that a mon-manifold model can easily be transformed to a 3-D wireframe model for the hull detail design system AutoDef or a FE model for the structural analysis system Nastran.