• 한국정밀공학회지
• /
• 제23권3호
• /
• pp.102-109
• /
• 2006

Several methods for PCB pattern inspection have been tried to detect fine detects in pad contours, but their low detection accuracy results from pattern variations originating from etching, printing and handling processes. The adaptive inspection algorithm has been newly proposed to extract minute defects based on movable segments. With gerber master images of PCB, vertex extractions of a pad boundary are made and then a lot of segments are constructed in master data. The pad boundary is composed of segment units. The proposed method moves these segments to optimal directions of a pad boundary and so adaptively matches segments to pad contours of inspected images, irrespectively of various pattern variations. It makes a fast, accurate and reliable inspection of PCB patterns. Its performances are also evaluated with several images.

• Journal of Power Electronics
• /
• 제19권3호
• /
• pp.691-701
• /
• 2019

To solve the problems in the contact charging of inspection robots, a wireless charging system for inspection robots and a control strategy are introduced in this paper. Circuit models of a wireless power system with a compound compensation circuit and a three-phase Class-D resonant inverter are set up based on circuit theory. An output voltage control method based on the equal spread regulation of the phase difference between adjacent phases and the parameter correction method in the primary compound compensation circuit are proposed. The dynamic characteristics of the key parameters varying with the secondary coil position are obtained to further investigate the adaptive location scheme during the access and exit processes of moving robots. Combining the output voltage control method and the adaptive location scheme, a transition control strategy for the standby and operation modes of the wireless charging systems for inspection robots is put forward to realize the system characteristics including the low standby power in the standby mode and the high receiving power in the operation mode. Finally, experiments are designed and conducted to verify the correctness of the theoretical research.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1994년도 추계학술대회 논문집
• /
• pp.748-754
• /
• 1994

This paper deals with a geometric error simulator, measurement and inspection of workpiece errors on the machine tools, and identification and compensation methodology of thermal errors in machining centers. In order to raise the machining accuracy of workpieces a measurement and inspection system on the machine tool is developed. By using MPPGT module Manual and CNC type CMMs are realized on the machining centers. To compensate for geometric and thermal deformation errors of machining centers, a real time and an off line geometric adaptive control system were developed on the machining centers. A vertical and a horizontal machining center equipped with FANUC 0MC were used for experiments. Performance of the systems were confirmed with a large amount of experiment.

• 반도체디스플레이기술학회지
• /
• 제10권1호
• /
• pp.113-118
• /
• 2011

This paper proposes computer visual inspection algorithms for PCB defects which are found in a manufacturing process. The proposed method can detect open circuit and short circuit on bare PCB without using any reference images. It performs adaptive threshold processing for the ROI (Region of Interest) of a target image, median filtering to remove noises, and then analyzes connected components of the binary image. In this paper, the connected components of circuit pattern are defined as 6 types. The proposed method classifies the connected components of the target image into 6 types, and determines an unclassified component as a defect of the circuit. The analysis of the original target image detects open circuits, while the analysis of the complement image finds short circuits. The machine vision inspection system is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiment results show that the proposed algorithms are quite successful.

• 반도체디스플레이기술학회지
• /
• 제9권3호
• /
• pp.59-63
• /
• 2010

This paper proposes computer visual inspection algorithms for various LCD defects which are found in a manufacturing process. Modular vision processing steps are required in order to detect different types of LCD defects. Those key modules include RGB filtering for pixel defects, gray-scale morphological processing and Hough transform for line defects, and adaptive threshold for spot defects. The proposed algorithms can give users detailed information on the type of defects in the LCD panel, the size of defect, and its location. The machine vision inspection system is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiment results show that the proposed algorithms are quite successful.

• 반도체디스플레이기술학회지
• /
• 제13권1호
• /
• pp.51-55
• /
• 2014

In this paper, an hybrid automatic focusing method has been proposed for speedy and reliable measurement and inspection in industry. It can improve reliability of focusing position by using not a focusing measure but the hybrid one that is incorporated with sobel operator and auto-correlation. Also, it can not only reduce control time of focusing position using adaptive step size, but also improve accuracy of focusing position by gaussian interpolation. Its performance is verified by experiments. It is expected that it can apply to optical system for measurement and inspection in industry fields.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집B
• /
• pp.253-258
• /
• 2001

This paper introduces a simple nonlinear adaptive control method for pipeline inspection gauge (PIG) flow in natural gas pipeline. The dynamic behavior of the PIG depends on the different pressure across its body and the bypass flow through it. The system dynamics includes: dynamics of driving gas flow behind the PIG, dynamics of expelled gas in front of the PIG, and dynamics of the PIG. The method of characteristics (MOC) and Runger-Kuta method are used to solve the dynamics of flow. The PIG velocity is controlled through the amount of bypass flow across its body. A simple nonlinear adaptive controller based on the backstepping method is introduced. To derive the controller, three system parameters should be measured: the PIG position, its velocity and the velocity of bypass flow across the PIG body. The simulation has been done with a pipeline segment in the KOGAS low pressure system, Ueijungboo-Sangye line to verify the effectiveness of the proposed controller. Three cases of interest are considered: the PIG starts to move at its launcher, the PIG arrives at its receiver and the PIG restarts after stopping in the pipeline by obstruction. The simulation results show that the proposed nonlinear adaptive controller attained good performance and can be used for controlling the PIG velocity.

• 전자공학회논문지
• /
• 제52권9호
• /
• pp.147-152
• /
• 2015

지금까지의 전차선 검측 시스템은 검측차량을 이용하여 검사구간을 주행 한 후 결과를 산출하였다. 이것은 아열대기후로의 변화에 인한 자연 환경의 급변과 450Km/h급 고속철도 차량의 등장으로 변화가 요구된다. 이에 고속 주행환경과 노반정보를 반영하는 융합 가변형 전차선 검측시스템의 구조를 연구하였다. 기존의 시스템은 전차선에 한정하여 마모의 정도를 판단하였다. 이에 비해 본 논문에서는 검지를 위하여 참조하는 정보를 검측대상의 영상정보에 추가하여 음향정보를 융합하였고, 지형정보에 따라 검지빈도와 정밀도를 가변적으로 적용함으로써 시설물 검측에 대한 기본적인 모델을 제안하였다.

• 반도체디스플레이기술학회지
• /
• 제12권2호
• /
• pp.57-61
• /
• 2013

This paper presents adaptive neuro-fuzzy inference based defect detection method for various defect types, such as micro-crack, fingerprint and contamination, in heterogeneously textured surface of polycrystalline solar wafers. Polycrystalline solar wafer consists of various crystals so the surface of solar wafer shows heterogeneously textures. Because of this property the visual inspection of defects is very difficult. In the proposed method, we use local binary feature and fuzzy reasoning for defect detection. Experimental results show that our proposed method achieves a detection rate of 80%~100%, a missing rate of 0%~20% and an over detection (overkill) rate of 9%~21%.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
• /
• pp.670-673
• /
• 1999

In this paper, we present a robust motion controller based on Adaptive-Fuzzy technique is proposed that multifunctional vehicle(MVR) for two DOF mobile robot can perform detailed inspection of physical conditions of sewage pipes as well as can effectively repair the damaged portions of the inner walls. The main difficulties in controlling this multifunctional robot vehicles lie in the fact that vehicles usually have three degrees of freedom in position and orientation in spite of having only two degrees of freedom for motion control in tracking mode. Decomposition of error between the reference posture and the current posture makes control of speed and steering possible. The Gyro compass part and Inclonometer of the robot is configured in order to realize position of robot. The proposed Adaptive-Fuzzy motion controller has two main characteristics: The one guarantees that the MVR follows the reference trajectory; the other one compensates the dynamics of the MVR. Simulation results are provided to validate the proposed controller. Experiments have been used to verify the effectiveness and robustness of the motion controller.