• Title/Summary/Keyword: CCD cameras

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3D Position Measurement & Coping using 2 CCD Cameras (2대의 CCD 카메라를 이용한 3차원 위치측정과 코핑)

  • Kang, Won-Chan;Shin, Suck-Doo;Kim, Young-Dong
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.51 no.2
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    • pp.87-93
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    • 2002
  • Accurate acquisition of surface geometries such as machined surfaces, biological surfaces, and deformed parts have been very important technique in scientific study and engineering, especially for system design, manufacturing and inspection. Two-camera method keeps accuracy more than double than mechanical method. In this paper, a new method is studied to acquire 3D geometric data of the small object such as a die in stone model. When the devices, cameras, laser beam and object are in a perfect plane, the calculation is measured by position error 0.025[mm] within. But this paper shows that arbitrarily positioned system can also be used to obtain 3D data. Also, this paper present a method to generate coping surface data with which CAM system can do for milling work.

A New 3D Shape Measurement Method using 2 CCD Cameras (2대의 CCD 카메라를 이용한 새로운 3차원 형상 측정법)

  • Kim, Jang-Ju;Jung, Gook-Young
    • Journal of Technologic Dentistry
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    • v.24 no.1
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    • pp.73-81
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    • 2002
  • Accurate acquisition of surface geometries such as machined surfaces, biological surfaces, and deformed parts have been very important technique in scientific study and engineering, expecially for system design, manufacturing and inspection. Two camera method is relatively simple with an acceptable accuracy. In this paper, a new method is studied to acquire 3D geometric data of the small object such as a die in stone model. When the devices, cameras, laser beam and object are in a perfect plane, the calculation becomes very simple with less error. But this paper shows that arbitrarily positioned system can also be used to obtain 3D data.

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CALOS : Camera And Laser for Odometry Sensing (CALOS : 주행계 추정을 위한 카메라와 레이저 융합)

  • Bok, Yun-Su;Hwang, Young-Bae;Kweon, In-So
    • The Journal of Korea Robotics Society
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    • v.1 no.2
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    • pp.180-187
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    • 2006
  • This paper presents a new sensor system, CALOS, for motion estimation and 3D reconstruction. The 2D laser sensor provides accurate depth information of a plane, not the whole 3D structure. On the contrary, the CCD cameras provide the projected image of whole 3D scene, not the depth of the scene. To overcome the limitations, we combine these two types of sensors, the laser sensor and the CCD cameras. We develop a motion estimation scheme appropriate for this sensor system. In the proposed scheme, the motion between two frames is estimated by using three points among the scan data and their corresponding image points, and refined by non-linear optimization. We validate the accuracy of the proposed method by 3D reconstruction using real images. The results show that the proposed system can be a practical solution for motion estimation as well as for 3D reconstruction.

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Automatic Color Recognition System for Stockigt Sizing Test (I) - Bias of Stockigt sizing test based on observer's subjectiveness - (스테키히트 시험용 자동 발색 인지 시스템 개발을 위한 기초연구(I) - Stockigt 사이즈도 시험법에 영향을 주는 요인 분석 -)

  • 김재옥;김철환;박종열
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.1
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    • pp.1-8
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    • 2004
  • One of the most frequently used method for measurement of the degree of sizing (viz., hydrophobicity) is the Stockigt test. However, the Stockigt test was influenced by various factors such as dropping height, dropping amount, dropping speed and viewing angle. The resultant data of the sizing degree on the same specimen also varied according to different testers. Thus, the Stockigt test should be modified to be regarded as a highly reliable and reproducible standard method. For modifying the Stockigt test, it was required to quantify red coloration by reaction between 1% ferric chloride and 2% ammonium thiocyante during Stockigt testing. The cameras capturing the serial images during the red coloration process were the CMOS (Complementary Metal Oxide Semiconductor)-type and CCD (Charge Coupled Device)-type cameras. For measurement based on KS M 7025, the CCD-type camera must be used due to its high resolution, and on the other hand, for measurement based on Tappi Useful Method 429, the CMOS-type camera may be used owing to its low resolution. It was needed to covert the RGB values of a droplet image into HSV(Hue, Saturation, and Value) values because the human eyes are much closer to HSV than RGB. Among HSV values, the Hue value was accepted as the most reliable index consistent with the red coloration process by excluding the surrounding conditions such as light, tester's movement etc.

Estimation of Electron Dose Rate using CCD Camera (CCD 카메라를 이용한 전자빔 조사량의 예측)

  • Kim, Jin-Gyu;Kim, Young-Min;Kim, Youn-Joong;Lee, Sang-Hee;Hong, Ki-Min;Oh, Sang-Ho
    • Applied Microscopy
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    • v.39 no.1
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    • pp.79-83
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    • 2009
  • We report a useful method to estimate the electron dose rate which may be a decisive factor to characterize sample properties. Even though most mircoscopes have their own exposure meters, there are several practical concerns when such exposure meters are used to measure the electron dose rate: 1) Specimen should be avoided within the entire area of exposure meter; 2) beam current has to be always recorded whenever the operation mode is changed; 3) the electron dose rate can not be calculated for the beam current beyond the detectable range. To overcome these limitations, we suggest a useful method which utilize a CCD (charge coupled device) camera which is now a popular detector to obtain the final electron micrographs. We have evaluated the CCD sensitivity using the linear relationship between electron current on the exposure meter and counter ratio on the CCD camera which are built in KBSI-HVEM (high voltage electron microscope). Applying the new method, we obtained the CCD sensitivity which are approximately 0.039 counts/$e^-$ and 1.37 counts/$e^-$ for the Top-TV and the HV-GIF CCD cameras, respectively.

Depth error calibration of maladjusted stereo cameras for translation of instrumented image information in dynamic objects (동영상 정보의 계측정보 전송을 위한 비선형 스테레오 카메라의 오차 보정)

  • Kim, Jong-Man;Kim, Yeong-Min;Hwang, Jong-Sun;Lim, Byung-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05b
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    • pp.109-114
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    • 2003
  • Depth error correction effect for maladjusted stereo cameras with calibrated pixel distance parameter is presented. The camera calibration is a necessary procedure for stereo vision-based depth computation. Intra and extra parameters should be obtain to determine the relation between image and world coordination through experiment. One difficulty is in camera alignment for parallel installation: placing two CCD arrays in a plane. No effective methods for such alignment have been presented before. Some amount of depth error caused from such non-parallel installation of cameras is inevitable. If the pixel distance parameter which is one of intra parameter is calibrated with known points, such error can be compensated in some amount. Such error compensation effect with the calibrated pixel distance parameter is demonstrated with various experimental results.

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Focus Control for CCD Camera using Annealing Algorithm (어닐링 알고리즘을 이용한 CCD 카메라 초점 제어)

  • 이관용;임신영;조성원
    • Journal of the Korean Institute of Intelligent Systems
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    • v.10 no.5
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    • pp.459-465
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    • 2000
  • In this paper, we propose a method for controlling camera focus in the short distance by analyzing NTSC signal of a CCD camera. When the distance between a camera and an object is less than about 1 meter, the existing CCD cameras with auto-focusing function are hard to acquire the proper images because they focus on the protruding minute parts ofthe object without taking into account the whole state of the object. To solve such a problem, we use an annealing algorithm to control the motor of a camera by analyzing the overall signal obtained from the camera. By doing so, we can acquire the adequate images at the near distance. The proposed method will be used for a personal identification system by human iris patterns.

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CFWC Scheme for Width Control using CCD Measurement System and Fuzzy PID Controller in Hot Strip Mills (CCD 폭 측정 시스템 및 퍼지 PID를 이용한 CFWC 제어기 설계)

  • Park, Cheol Jae
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.11
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    • pp.991-997
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    • 2013
  • In this paper, we propose a CFWC (CCD and fuzzy PID based width control) scheme to obtain the desired delivery width margin of a vertical rolling mill in hot strip process. A WMS(width measurement system) is composed of two line scan cameras, an edge detection algorithm, a glitch filter, and so on. A dynamic model of the mill is derived from a gauge meter equation in order to design the fuzzy PID controller. The controller is a self-learning structure to select the PID gains from the error and error rate of the width margin. The effectiveness of the proposed CFWC is verified from simulation results under a width disturbance of the entry in the mill. Using a field test, we show that the performance of the width control is improved by the proposed control scheme.

Inspection of Calandria Reactor Area of Wolsung NPP using Thermal Infrared and CCD Images (CCD와 적외선 열영상의 다중영상을 이용한 월성원자력발전소의 칼란드리아 전면부 점검)

  • Cho, Jai-Wan;Choi, Young-Soo;Kim, Chang-Hoi;Seo, Yong-Chil;Kim, Seung-Ho
    • Proceedings of the KIPE Conference
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    • 2002.07a
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    • pp.711-714
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    • 2002
  • Thermal infrared camera have poor image qualities compared to commercial CCD cameras, as in contrast, brightness, and. resolution. To compensate the poor Image quality problems associated with the thermal infrared camera, the technique of superimposing thermal infrared image into real ccd image is proposed. The mobile robot KAEROT/m2, loaded with sensor head system at the mast, is entered to monitor leakage of heavy water and thermal abnormality of the calandria reactor area in overhaul period. The sensor head system is composed of thermal infrared camera and cod camera In parallel. When thermal abnormality on observation points and areas of calandria reactor area is occurred, unusual hot image taken from thermal infrared camera is superimposed on real CCD image. In this inspection experiment, more accurate positions of thermal abnormalities on calandria reactor area can be estimated by using technique of mapping thermal infrared image into CCD image, which include characters arranged in MPOQ order.

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Development of a Stereoscopic PTV (스테레오 PTV법의 개발)

  • Doh Deog Hee;Lee Won Je;Cho Yong Beom;Pyeon Yong Beom
    • Journal of the Korean Society of Visualization
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    • v.1 no.1
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    • pp.92-97
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    • 2003
  • A new Stereoscopic PTV was developed using two CCD cameras, stereoscopic photogrammetry based on a 3D-PTV principle. Virtual images were produced for the benchmark test of the constructed Stereoscopic PTV technique. The arrangement of the two cameras was based on angular position. The calibration of cameras and the pair-matching of the three-dimensional velocity vectors were based on the Genetic Algorithm based 3D-PTV technique. The constructed Stereoscopic PTV technique was tested on the standard images of the impinged jet proposed by VSJ. The results obtained by the constructed system showed good agreements with the original data.

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