• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
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• pp.373-374
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• 2008

To prevent an insulator failure, a new inspection system is presented for 154kV insulator strings. The inspection system detects fault insulators by measuring resistance and voltage of each insulators in the 154kV insulator string. The inspection instrument obtains autonomously insulation resistance and assigned voltage along the insulator string. The insulator inspection instrument is manipulated by two operators. In addition, a set of mechanism is applied to prevent the system from being reset under live-line condition. We confirmed its effectiveness through experiments.

• International journal of advanced smart convergence
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• 제8권3호
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• pp.39-45
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• 2019

This paper presents an optical technique for the three-dimensional (3D) shape inspection of micro solder balls used in ball-grid array (BGA) packaging. The proposed technique uses an optical source composed of spatially arranged light-emitting diodes (LEDs) and the results are derived based on the specular reflection characteristics of the micro solder balls for BGA A vision system comprising a camera and LEDs is designed to capture the reflected images of multiple solder balls arranged arbitrarily on a tray and the locations of the LED point-light-source reflections in each ball are determined via image processing, for shape inspection. The proposed methodology aims to determine the presence of defects in 3D BGA shape using the statistical information of the relative positions of multiple BGA balls, which are included in the image. The presence of the BGA balls with large deviations in relative position imply the inconsistencies in their shape. Experiments were conducted to verify that the proposed method could be applied to inspection without sophisticated mechanism and productivity problem.

• 품질경영학회지
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• 제18권2호
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• pp.18-24
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• 1990

The location of inspection stations is a significant component of production systems. In this paper, a prototype expert system is designed for deciding the optimal location of inspection stations. The production system is defined as a single channel of n serial operation stations. The potential inspection station can be located after any of the operation stations. Nonconforming units are generated from a compound binomial distribution with known parameters at any given operation station. Traditionally Dynamic programming, Zero-one integer programming, or Non-linear programming techniques are used to solve this problem. However a problem with these techniques is that the computation time becomes prohibitively large when t be number of potential inspection stations are fifteen or more. An expert system has the potential to solve this problem using a rule-based system to determine the near optimal location of inspection stations. This prototype expert system is divided into a static database, a dynamic database and a knowledge base. Based on defined production systems, the sophisticated rules are generated by the simulator as a part of the knowledge base. A generate-and-test inference mechanism is utilized to search the solution space by applying appropriate symbolic and quantitative rules based on input data. The goal of the system is to determine the location of inspection stations while minimizing total cost.

• 한국정밀공학회지
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• 제21권12호
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• pp.92-99
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• 2004

The formation degree of sustain (ITO pattern) decides quality of PDP (Plasma Display Panel). For this reason, it makes efforts in searching defects more than 30 un as 100%. Now, the existing inspection is dependent upon naked eye or microscope in off-line PDP manufacturing process. In this study developed prototype inspection system of PDP 170 glass is based on line-scan mechanism. Developed system creates information that detects and sorts kinds of defect automatically. Designed inspection technology adopts multi-vision method by slip-beam formation for the minimum of inspection time and detection algorithm is embodied in detection ability of developed system. Designed algorithm had to make good use of kernel matrix that draws up an approach to geometry. A characteristic of defects, as pin hole, substance, protrusion, are extracted from blob analysis method. Defects, as open, short, spots and et al, are distinguished by line type inspection algorithm. In experiment, we could have ensured ability of inspection that can be detected with reliability of up to 95% in about 60 seconds.

• International Journal of Precision Engineering and Manufacturing
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• 제7권3호
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• pp.18-23
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• 2006

The formation degree of sustain (ITO pattern) determines the quality of a PDP (Plasma Display Panel). Thus, in the present study, we attempt to detect 100% of the defects that are larger than $30{\mu}m$. Currently, the inspection method in the PDP manufacturing process is dependent upon the naked eye or a microscope in off-line mode. In this study, a prototype inspection system for PDP ITO patterned glass is developed. The developed system, which is based on a line-scan mechanism, obtains information on the defects and sorts the defects by type automatically. The developed inspection system adopts a multi-vision method using slit-beam formation for minimum inspection time and the detection algorithm is embodied in the detection ability. Characteristic defects such as pin holes, substances, and protrusions are extracted using the blob analysis method. Defects such as open, short, spots and others are distinguished by the line type inspection algorithm. It was experimentally verified that the developed inspection system can detect defects with reliability of up to 95% in about 60 seconds for the 42-inch PDP panel.

• 한국구조물진단유지관리공학회 논문집
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• 제15권5호
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• pp.160-168
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• 2011

성수대교 삼풍백화점 붕괴사고 등을 계기로 유지관리 분야의 중요성이 대두되면서 1995년 시설물의안전관리에관한특별법이 제정되어 점검 진단이 실시되는 등 본격적인 유지관리체제가 시작됐다. 그러나 점검 진단의 역사가 일천한 관계로 점검 진단에 대한 기술수준이 낮았고 연구 성과 또한 미흡하여 부실 점검 진단에 대한 우려가 상존해 있었다. 이에 2002년 평가제도가 도입되면서 부실 점검 진단 비율이 지속적으로 낮아져 왔다. 그러나 최근 점검 진단 실시결과 평가실적에 따르면 향후 부실 점검 진단비율이 더 이상 낮아지기 힘든 경향을 보이고 있다. 이를 계기로 부실 점검 진단과 관련하여 관련기관의 설문조사와 메커니즘 측면에서 고찰하므로서, 부실 점검 진단이 초래되는 근원적인 문제점을 나열하였고, 이를 바탕으로 현행 평가제도의 개선방향을 제시 하고자 하였다.

• 한국가스학회지
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• 제12권2호
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• pp.110-117
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• 2008

정량적 원인분석이 가능한 위험기반검사 프로그램(KS-RBI Ver. 3.0)을 사용하여 화학설비의 위험도를 산출하고, 설비의 위험도를 경감할 수 있는 방안을 모색하였다. 그 결과, 손상메커니즘, 검사횟수 및 검사 유효성을 고려하여 사고발생 가능성(LOF)을 줄이고, 검출, 차단 및 완화 시스템의 수준을 변경하여 사고 피해 크기(COF)를 감소시킴으로써 설비의 위험도를 낮출 수 있었다. 특히, 고 위험도를 낮추기 위해서는 LOF와 COF를 동시에 낮출 수 있는 방안을 모색할 필요가 있으며, 설비의 위험도를 경감함으로써 설비의 안전성 향상으로 사고피해 감소는 물론 검사주기 연장으로 검사비용 및 인건비 절감 등을 기대할 수 있다.

• 로봇학회논문지
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• 제7권2호
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• pp.83-91
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• 2012

In this paper, we propose a cable climbing robot which can climb up and down the cables in the bridges. The robot mechanism consists of three parts: a wheel based driving mechanism, adhesion mechanism, and safe landing mechanism. The wheel based driving mechanism is driven by tooth clutches and motors. The adhesion mechanism plays the role of maintaining adhesion force by a combination of pantograph, ball screw, and springs even when the power is lost. The safe landing mechanism is developed for guaranteeing the safety of the robot during operations on cables. It can make the robot fall down with reduced speed by dissipating the gravitational forces. The robot mechanism is designed and manufactured for validating its effectiveness.

• 조명전기설비학회논문지
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• 제21권8호
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• pp.71-80
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• 2007

독립형 비전을 사용한 자동차용 부품인 밸브씰 검사 시스템을 개발하고 구성하였다. 구성부품은 8대의 독립형 CCD카메라, 검사를 위해 밸브 씰을 공급해 주는 기구장치로서 구성되었다. 2가지 형태의 밸브 씰 불량 유형에 대한 영상처리 알고리즘을 제안하였으며, 알고리즘의 효율성은 실험을 통하여 입증하였고 정밀한 상태로 0.7초 이내에 검사가 완료되도록 하였다. 이러한 검사 시스템은 자동차 부품산업에서 다양한 응용 분야로서 사용될 수 있을 것이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.816-821
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• 2004

The outlet feeder pipe thinning in a PHWR (Pressured Heavy Water Reactor) is caused by high pressure steam flow inside the pipe, which is a well known degradation mechanism called FAC (Flow Assisted Corrosion). In order to monitor the degradation, the thickness of the outlet bends closed to the exit of the pressure tube should be measured and analyzed at every official overhaul. This paper develops an automatic feeder pipe inspection system that can minimize the irradiation dose by automating the measurement process. The robot can move by itself on the feeder pipe by using an inch worm mechanism, which is constructed by two gripper bodies that can fix their body on the pipe and one extendable and retractable body connected the two gripper bodies to move forward and backward.