• The KIPS Transactions:PartA
• /
• v.11A no.4
• /
• pp.235-242
• /
• 2004

When manufacturing information and communication device that consists of lots of part, it is important to improve the quality of the produced system by inspecting the system accurately and exclude the defected part. In case of LCD which is recently in a great demand, the inspection process of the nut which bonds the back frame to protect the LCD panel has to be done by human labor. It highly required an automatic inspection system which can inspect the nut without wasting human resources. In this paper, we describe the process of developing a system which automatically inspect the status of nuts inserted during the manufacturing of LCD. The nut inspection vision system developed measures the number of nut's spiral, the distance between pitches, the width of a pitch, and the inside diameter of nut. We have adopted lens with high magnifying power and calibration tool and intended to produce automatic lighting for maintaining a stable environment for a high precision system. We also developed the algorithms for analyzing the nut. We apply the system to real factory field and verify that it is better than the man power in terms of error rate.

• 전자공학회논문지 IE
• /
• v.48 no.1
• /
• pp.16-24
• /
• 2011

In this paper, we developed a auto sorting system for T type welding nut using a vision inspector. We used edge and thread detection with histogram of image which is captured by machine vision camera. We also used a binary morphology operation for a detection of spot. As a result we performed numeric inspection of 0.1mm accuracy. This is impossible in old sorting system and inspector with naked eye. Also, we reduced the manufacturing unit cost to 25% and improved a production efficiency to 330%.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.5
• /
• pp.937-943
• /
• 2009

In this paper, the algorithm discriminating the existence and nonexistence of bolts and nuts using image processing in an automobile T-Bar influencing the vibration of a frame, is introduced. To distinct whether bolts and nuts exist or not, the features of bolts and nuts are learned, and then these feature values are matched using a statistical pattern matching algorithm. Furthermore, the minimum and maximum variation rate of pixel values are used since the matching rate is low with the large variation of pixel values of bolts and nuts in each image. The proposed method in this paper is very efficient in the automation of inspection requiring real time since the inspection time is significantly reduced compared with the conventional methods.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.9
• /
• pp.353-361
• /
• 2012

In this paper, we propose a improvement method of vision inspector for T type welding nut using an auto sorting system. We used edge and thread detection with histogram of image which is captured by machine vision camera. We also used a binary morphology operation for a detection of spot. A major problem in this vision inspector is abnormal operation caused by degradation of image acquired. These degradations caused by oil pollution on conveyer belt. For overcome this problem, we introduce a pre-processing using a masked histogram equalization on the image acquired. Histogram equalization is applied on masked region (nut part) for increase contrast. As a result, we can remove features caused by oil pollution on background and reduce a ratio of abnormal operation from 10.0 % to 0.2 %.

• Fire Science and Engineering
• /
• v.29 no.3
• /
• pp.21-30
• /
• 2015

In this study, we try to suggest measures to reduce leakage at a joint between CPVC piping for a sprinkler system and a pipe expansion through reviews of domestic and foreign standards and related tests. The quality of the waterproof rubber packing material between a valve socket and pipe expansion nut was examined. In the leak test, the valve socket material over the expansion part of the metal pipe nut was found to use a metal part or a schlorinated polyvinyl chloride pipe nut part. In addition, the KS B 0221 standard for parallel pipe threads with threaded and thread inspection criteria and inspection standards in order to ensure an acceptable quality of valve socket, there is a need to amend the regulations to comply with the KS B 5223 (screw thread limit gauges parallel pipe threads). We do not have detailed standards for expansion piping nuts for waterproof rubber ring material, so we need to amend the relevant criteria for EPDM material to be used with excellent waterproofing, for which both NBR and EPDM are currently used.

• Journal of Digital Convergence
• /
• v.16 no.3
• /
• pp.303-309
• /
• 2018

Computer vision technology is a component inspection to obtain a video image from the camera to the machine to perform the capabilities of the human eye with a field of artificial intelligence, and then analyzed by the algorithm to determine to determine the good and bad of production parts It is widely applied. Shape inspection method was used as how to identify the location of the start point and the end point of the search range, measure the height to the line scan method, in such a manner as to determine the presence or absence of the bolt tabs average brightness of the inspection area in a circular scan type value And the degree of similarity was calculated. The total time it takes to test in the test performance tests of two types of bolts tab enables test 300 min, and demonstrated the accuracy and efficiency of the inspection on the production line represented a complete inspection accuracy.

• Journal of Korea Multimedia Society
• /
• v.14 no.7
• /
• pp.895-904
• /
• 2011

In welding machine that executes existing spot welding, wrong operation of system has often occurs because of their mechanical motion that can be caused by a number of supply like the welding object. In exposed working environment for various situations such as worker or related equipment moving into any place that we are unable to exactly distinguish between good and not condition of nut. Also, in case of defective welding of nut, it needs various evaluation and analysis through image processing because the problem that worker should be inspected every single manually. Therefore in this paper, if the object was not stabilization state correctly, we have purpose to algorithm implementation that it is to reduce the analysis time and exact recognition as to improve system of image processing. As this like, as image analysis for assessment whether it is good or not condition of nut, in his paper, implemented algorithms were suggested and list by group and that it showed the effectiveness through more than one experiment. As the result, recognition rate of normality and error according to the estimation time have been shown as 40%~94.6% and 60%~5.4% from classification 1 of group 1 to classification 11 of group 5, and that estimation time of minimum, maximum, and average have been shown as 1.7sec.~0.08sec., 3.6sec.~1.2sec., and 2.5sec.~0.1sec.

• Journal of the Korea Convergence Society
• /
• v.9 no.10
• /
• pp.257-263
• /
• 2018

The purpose of this study is to develop an automatic inspection system for a part of the differential drive gear into the transmission. This technology will make using the microvision automatic test equipment and automatic test equipment microlaser. This is that the operator intends to make the defect rate 0 in the inspection stage of the product which has been carelessly processed. The equipment developed in this research project will be applied to many areas. Packaging companies, nut bolt processing company, precisely supplier for printing on top of the semiconductor, SMT, etc. The company wants to sell the vision inspection equipment for various applications. If the defective rate of 0 is achieved through this research project, it is also possible to secure a stable supply from the parent company, and to lay the foundations for exporting based on product reliability. When the automatic inspection system is applied to domestic automobile parts processing companies, the reliability of automobiles in Korea will be greatly increased.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.756-760
• /
• 2017

Meeting the growing demand deadlines, reducing the production cost and upgrading the quality control measurements are the reasons why the automotive part manufacturers are venturing into automation. Attaining these objectives is impossible with human inspection for many reasons. Accordingly, the introduction of inspection system purposely for door hinge bracket inspection is presented in this study as an alternative for human inspection. This proposal is designed to meet the demands, features and specifications of door hinge bracket manufacturing companies in striving for increased throughput of better quality. To improve demerits of this manual operation, inspection system is introduced. As the inspection algorithm, template matching algorithm is applied to distinguish the articles of good quality and the poorly made articles. Through the verification test of the inspection process algorithm and the similarity metric matching algorithm, the detection accuracy was 98%, and it was applied to the production site to contribute to the improvement of the productivity due to the decrease of the defective product.

• The Journal of the Acoustical Society of Korea
• /
• v.12 no.3
• /
• pp.5-12
• /
• 1993

볼트와 너트에 대한 초음파비파괴검사는 종파와 사각 횡파 기술을 사용하고 있는데 작은 결함신호는 자사산의 신호와 크기가 비슷해 구분이 되지 않는다. 본 논문에서는 나사산의 다중반사신호로부터 결함신호를 구분할 수 있는 방법을 제시한다. 종파를 사용하였을 경우 균열의 선단신호와 코너에서 반사되는 신호는 진행시간이 거의 같아 중첩되어 나타나지만 균열로 인한 Rayleigh파는 균열의 선단신호와 코너에서 반사되는 신호다음에 결함길이에 따른 미세한 진행시간을 가지고 나타난다. 이와는 다르게 횡파를 사용하였을때의 균열의 선단신호는 코너에서 반사되는 신호보다 앞에 나타난다. 이러한 나사산에 존재하는 결함의 선단신호를 기준으로 순방향 또는 역방향으로 반사되는 신호로부터 작은 결함신호도 구분할 수 있고 그 크기를 정량적으로 계산할 수 있다.