• 한국정밀공학회지
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• 제20권4호
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• pp.223-229
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• 2003

Tool wear monitoring is an important technique in the flexible manufacturing system. This paper studies the end mill wear detection using CCD camera and pattern recognition method. When the end mill working in the machining center, the bottom edge of the end mill geometry change, this information is used. The CCD camera grab the new and worn tool geometry and the area of the tool geometry was compared. In this result, when the values of the subtract worn tool from new tool end in 200 pixels, it decides the tool life. This paper proposed the new method of the end mill wear detection.

• 한국정밀공학회지
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• 제23권1호
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• pp.64-71
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• 2006

Ultraprecision machining and MEMS technology have been taken more and more important position in machining of microparts. Micro endmilling is one of the prominent technology that has wide spectrum of application field ranging from macro parts to micro products. Also, the method of micro-grooving using micro endmill is used widely owing to many merit, but has problems of precision and quality of products due to tool wear and tool fracture. This investigation deals with state monitoring using acoustic emission(AE) signal in the micro-grooving. Characteristic evaluation of AE raw signal, AE hit and frequency analysis for condition monitoring is presented. Also, the feature extraction of AE signal directly related to machining process is executed. Then, the distinctive micro endmill state according to the each tool condition is classified by the fuzzy C-means algorithm.

• 한국산업정보학회논문지
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• 제21권4호
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• pp.43-53
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• 2016

본 논문에서는 선반가공에서 모터전류 신호를 이용하여 공구 파손을 감지하는 연구를 수행하였다. 본 연구에서는 먼저, 다양한 환경 변화에 대한 모터 전류 신호의 특성을 명확하게 파악하기 위해 신뢰성을 갖고 있는 절삭력과 모터전류 사이의 상관관계를 분석하였으며, 이를 기준으로 하여 공구파손시의 모터 전류 신호에 대해 분석하였다. 다양한 가공 실험을 통하여 절삭조건 변화에 따른 절삭력 신호와 주축 모터전류 신호의 정적 성분에 대한 상관관계를 분석하였다. 그 결과 절삭력과 모터전류 사이에 비례관계가 존재한다는 것을 알 수 있었으며, 이를 통해 모터 전류 신호만으로도 공구 파손을 감지 할 수 있을 것으로 판단하였다. 한편, 다양한 공구 파손 실험을 통해 절삭력과 모터전류 신호 사이에도 높은 상관관계가 존재함을 확인하였다. 이러한 공구파손 신호와 일반적인 선반가공의 가공신호를 분류하기 위해 본 논문에서는 새로운 방식의 감지 방법을 제시하였다. 제시한 분류 방법에 대해 여러 차례에 걸친 검증을 통해 공구파손 감지를 위한 모터 전류신호의 감지 신뢰성을 평가하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.1059-1060
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• 2009

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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• pp.14-18
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• 2001

Rise in cutting force causes tool damage and worsens product quality resulting in machining accuracy deterioration. Especially, fragile material cutting brings about breakage of material and worsens product surface quality. In this study, we trace the locus of cutting force and examine the machined surface corresponding to the cutting force loci. and build up a monitoring system for deciding normal operation or not of cutting process.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.162-167
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• 2005

Recently, the advanced industries using micro parts are rapidly growing. Micro endmilling is one of the prominent technology that has wide spectrum of application field ranging from macro to micro parts. Also, the method of micro-grooving using micro endmilling is used widely owing to many merit, but has problems of precision and quality of products due to tool wear and tool fracture. This study deals with condition monitoring using acoustic emission(AE) signal in the micro-grooving. First, the feature extraction of AE signal directly related to machining process is executed. Then, the distinctive micro endmill state according to the each tool condition is classified by using the fuzzy C-means algorithm, which is one of the methods to recognize data patterns. These result is effective monitoring method of micro endmill state by the AE sensing techniques which can be expected to be applicable to micro machining processes in the future.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권11호
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• pp.489-494
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• 2013

다양한 서비스를 제공하는 인터넷 환경에서 수많은 개인정보가 활용되고 있으나, 개인 사용자는 자신의 어떠한 개인 정보가 전송되는지 모르고 있다. 본 논문에서는 네트워크 패킷 내에 개인정보를 지속적으로 모니터링하고, 유출 여부를 사용자에게 알려주는 모니터링 도구 개발을 목표로 한다. 이를 위하여 개인정보 모니터링 도구를 구현하고, 그 결과를 분석한다. 또한 기업 기밀정보 유출 방지, 의료정보 유출 방지 등 직접 활용할 수 있는 응용 분야에 대해 제시한다. 본 연구 결과는 개인정보 유출 방지에 기여함으로써 개인정보를 대상으로 하는 다양한 사이버 침해를 줄이는데 기여할 수 있을 것으로 판단한다.

• 소성∙가공
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• 제15권1호
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• pp.82-88
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• 2006

In this paper, the web-based monitoring system is developed for the effective process monitoring of mold manufacturing using web. In developed system, the cutting force for monitoring the manufacturing condition is measured using hall-sensor that is low cost and useful to be installed in a machine tool indirectly. Specially, the current of main spindle in a machine tool is converted into cutting force by various experiments. For effective web-based monitoring, the program which runs in the local computer of client is made to exchange message between a server and a client by making of ActiveX control and the result of manufacturing is shown on web-browser by Ch language. The developed system in this study is the foundation of establishing E-manufacturing in mold factory.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 금형가공,미세가공,플라스틱가공 공동 심포지엄
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• pp.121-125
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• 2005

In this paper, the web-based monitoring system is developed for the process monitoring of mold manufacturing. The cutting force is measured by hall-sensors which is low cost and useful to be installed in machine tool indirectly. Specially, the current of main spindle in machine tool is converted into cutting force by various experiments. For effective emote monitoring, the interface that is able to offer the information of current process and cutting signal to client is establish.

• 한국정밀공학회지
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• 제2권1호
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• pp.62-71
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• 1985

This is a study on the monitoring technique in tool failure and tool life by AE method. The relation between amplitude level of AE signal and flank wear width was studied by experiments. The relation between amplitude level of AE signal and tool life was also studied. As the result, it was observed that amplitude level of AE signal was only affected by cutting velocity. Amplitude level of AE signal was directly proportional to flank wear width and the increasing rate was related to cutting velocity. So, the relation between amplitude level of AE signal and tool life was represented as follow: $CT^n$ = $AE_{rms}$ where, n=0.35 C=9.5*$10^{-2}$