Studies of Automated Inspection and Process Control of Arc Circuits in Bendable Flexible Printed Circuit (FPC) Board Industry

• Main Authors: Ying-Xiang Liao, 廖英翔
• Other Authors: Hong-Dar Lin
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/98248808216653014668

碩士 === 朝陽科技大學 === 工業工程與管理系碩士班 === 90 === Flexible printed circuit board (FPC) has been used extensively because of its flexibility. Tracks on the FPC are different from those on the printed circuit board (PCB) because of the bendability. Track’s shapes on the PCB are lines and corners but track’s shapes on the FPC are lines and arcs. Three reasons for the difference of the track’s shapes between FPC and PCB. First, to decrease electromagnetic interference when an electron current pass by a track turn. Second, to avoid stress appears at the track turn on the FPC. Stress can destroy the track’s structure on the flexible printed circuit board. Third, to match up the shape of a product body and to avoid the track pass through the position which has an electric component. Tracks on the FPC are designed as arcs when making a turn. Since the requirement of FPC manufacturing skills is getting more precisely. This tendency needs more techniques to conquer these difficulties. This research is going to study the automated inspection and process control of the track arcs of the FPC industry. In this research, computer vision techniques are used to obtain the coordinates of the tracks on the FPC. A revised curvature method is proposed to compute the curvatures of the tracks. Then, the CUSUM algorithm is applied to obtain the coordinates of the corner of the tracks. Based on the information of the corner, we can measure the features of every track arc segment. Finally, these features can be utilized to develop a process control model based on the CUSUM control chart for the track process control of the FPC. This research proposes and implements a computer vision system to find out the corner of the track by using “Curvature and CUSUM algorithm”.This method can detect 98.8 corners in 100 corners. And a process control model of the track arcs based on CUSUM control chart is also developed. This research contributes a solution to the common inspection and process control problems of the FPC track process. Keyword：Computer-aided automatic inspection; Process control; Curveture; CUSUM algorithm; Track arc detection; Flexible printed circuit board; Bendability.