• 한국정보과학회논문지:소프트웨어및응용
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• 제27권1호
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• pp.33-40
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• 2000

자동공정계획은 CAD 모델을 자동적으로 해석하여 CAM을 구동시키는 것을 목표로 하는데, 이를 위해서는 우선 CAD 모델로부터 특징형상을 인식하여야 한다. 특징형상 인식에 관한 연구는 근 20년간의 역사를 가지고 있지만, 그 연구 성과는 실용화되지 못하고 있다. 그 이유 중 하나는, 특징형상 인식과 자동공정계획 연구가 분리되어 진행되어왔기 때문이다. 본 연구에서는 인공지능 기법을 토대로 이 두 분야를 통합하여, 제조가능한 특징형상을 인식하고, 셋업을 최소화하며, 특징형상 간의 의존 관계를 설정하고, 최적의 가공 순서를 결정하였다.

• 한국정밀공학회지
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• 제20권8호
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• pp.144-152
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• 2003

The purpose of this paper is to establish an effective inspection system by using OMM (On-Machine Measurement) system based PC-NC. This system can reduce manufacturing lead time because part is inspected each process. Inspection process planning is accomplished by determining the number of measuring points, their location, measuring path using fuzzy logic, Hammersley method, traveling salesperson problem. Inspection with contacted sensor improve quality as inspection feature is developed to based machining feature. This method is tested by simulation and experiment, then analyzed measuring data and geometry tolerance.

• Journal of Mechanical Science and Technology
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• 제19권2호
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• pp.549-557
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• 2005

The requirements of multi-resolution models of feature-based solids, which represent an object at many levels of feature detail, are increasing for engineering purposes, such as analysis, network-based collaborative design, virtual prototyping and manufacturing. To provide multi-resolution models for various applications, it is essential to generate adequate solid models at varying levels of detail (LOD) after feature rearrangement, based on the LOD criteria. However, the non-commutative property of the union and subtraction Boolean operations is a severe obstacle to arbitrary feature rearrangement. To solve this problem we propose history-based Boolean operations that satisfy the commutative law between union and subtraction operations by considering the history of the Boolean operations. Because these operations guarantee the same resulting shape as the original and reasonable shapes at the intermediate LODs for an arbitrary rearrangement of its features, various LOD criteria can be applied for multi-resolution modeling in different applications.

• 한국CDE학회논문집
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• 제10권6호
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• pp.432-443
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• 2005

Recent three-dimensional feature-based CAD systems based on solid or non-manifold modelling functionality have been widely used for product design in manufacturing companies. When product models associated with features are used in various downstream applications such as analysis, however, simplified and abstracted models at various levels of detail (LODs) are frequently more desirable and useful than the full detailed model. To provide multi-resolution models, the features need to be rearranged according to a criterion that measures the significance of the feature. However, if the features are rearranged, the resulting shape is possibly different from the original because union and subtraction Boolean operations are not commutative. To solve this problem, in this paper, the new concept of the effective zone of a feature is defined and identified using Boolean algebra. By introducing the effective zone, an arbitrary rearrangement of features becomes possible and arbitrary LOD criteria may be selected to suit various applications. Besides, because the effective zone of a feature is independent of the data structure of the model, the multi-resolution modelling algorithm based on the effective zone can be implemented on any 3D CAD system based on conventional solid representations as well as non-manifold topological (NMT) representations.

• 한국CDE학회논문집
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• 제10권6호
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• pp.444-454
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• 2005

Recently, the requirements of multi-resolution models of a solid model, which represent an object at multiple levels of feature detail, are increasing for engineering tasks such as analysis, network-based collaborative design, and virtual prototyping and manufacturing. The research on this area has focused on several topics: topological frameworks for representing multi-resolution solid models, criteria for the level of detail (LOD), and generation of valid models after rearrangement of features. As a solution to the feature rearrangement problem, the new concept of the effective zone of a feature is introduced in the former part of the paper. In this paper, we propose a feature-based non-manifold modeling system to provide multi-resolution models of a feature-based solid or non-manifold model on the basis of the effective feature zones. To facilitate the implementation, we introduce the class of the multi-resolution feature whose attributes contain all necessary information to build a multi-resolution solid model and extract LOD models from it. In addition, two methods are introduced to accelerate the extraction of LOD models from the multi-resolution modeling database: the one is using an NMT model, known as a merged set, to represent multi-resolution models, and the other is storing differences between adjacent LOD models to accelerate the transition to the other LOD. We also suggest the volume of the feature, regardless of feature type, as a criterion for the LOD. This criterion can be used in a wide range of applications, since there is no distinction between additive and subtractive features unlike the previous method.

• 한국생산제조학회지
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• 제7권1호
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• pp.69-74
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• 1998

In order to monitor the tool wear in milling operation, cutting force is measured as the tool wear increased. The digital signal processing methods are used to detect the tool wear . As AR parameter extract the feature of tool wear , it can be used as input parameter of pattern classifier. The FFT monitor the tool wear exactly , but it can not do real time signal processing. The band energy method can be used to real time monitoring of tool wear ,but int can degrade the exact monitoring.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.1100-1103
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• 2001

(1) By comparing and analyzing the distribution of brightness as domestic lamps and Japanese products go thinner and lighter, we set an effective design standard. (2) By comparing and analyzing the feature, brightness, chromaticity and uniformity of domestic LGPs and Japanese products, early home-manufacturing and stabilization in home-manufacturing are possible. (3) By comparing and analyzing the distribution of brightness as sheets are varied, we can design an ideal sheet composition.

• 한국생산제조학회지
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• 제9권3호
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• pp.111-122
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• 2000

It is difficult to make shape library for featrue-based modeling because free-form surface is various shaped complicated To make modeling using similar shape feature-based model is easy and fast. Recently RE(Reverse Engineering) technolo-gy is very convenient method to get free-form surface. This study develops surface editor which makes surface modeling to manipulate control points and this study We study on the effective model data management using database system.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.105-108
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• 2001

In this paper, comparing and analyzing the distribution of brightness as domestic lamps and Japanese products go thinner and lighter, we set an effective design standard. By comparing and analyzing the feature, brightness, chromaticity and uniformity of domestic LGPs and Japanese products, early home-manufacturing and stabilization in home-manufacturing are possible. By comparing and analyzing the distribution of brightness as sheets are varied, we can design an ideal sheet composition.

• International Journal of Precision Engineering and Manufacturing
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• 제2권3호
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• pp.69-78
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• 2001

This paper presents a process and operation planning system and an NC code post-processor for effective machining of press dies for production of cars. Based on the machining feature, major parts of press dies are categorized into 15 groups and a standard process plan is defined for each group. The standard process plan consists of a series of processes where a process is defined as a group of operations that can be done with one setup. Details such as cutting tools, cutting conditions, and tool paths are decided at the operation planning stage. At the final stage of process and operation planning, the NC code post-processor adjusts feedrates along the tool path to reduce machining time while maintaining the quality. The adjustment rule is selected based on the machining load estimated by virtual machining.