• Title/Summary/Keyword: High Accuracy

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Constrained High Accuracy Stereo Reconstruction Method for Surgical Instruments Positioning

  • Wang, Chenhao;Shen, Yi;Zhang, Wenbin;Liu, Yuncai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.10
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    • pp.2679-2691
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    • 2012
  • In this paper, a high accuracy stereo reconstruction method for surgery instruments positioning is proposed. Usually, the problem of surgical instruments reconstruction is considered as a basic task in computer vision to estimate the 3-D position of each marker on a surgery instrument from three pairs of image points. However, the existing methods considered the 3-D reconstruction of the points separately thus ignore the structure information. Meanwhile, the errors from light variation, imaging noise and quantization still affect the reconstruction accuracy. This paper proposes a method which takes the structure information of surgical instruments as constraints, and reconstructs the whole markers on one surgical instrument together. Firstly, we calibrate the instruments before navigation to get the structure parameters. The structure parameters consist of markers' number, distances between each markers and a linearity sign of each instrument. Then, the structure constraints are added to stereo reconstruction. Finally, weighted filter is used to reduce the jitter. Experiments conducted on surgery navigation system showed that our method not only improve accuracy effectively but also reduce the jitter of surgical instrument greatly.

Prediction of Welding Imperfection with Idealization of Welding and Their Accuracy (용접이상화에 의한 용접부정의 예측과 정도)

  • Lee, Jae-Yik;Chang, Kyong-Ho;Kim, You-Chul
    • Journal of Welding and Joining
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    • v.31 no.5
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    • pp.15-19
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    • 2013
  • In order to reduce a grand compute time in prediction of welding distortion and residual stress by 3D thermal elastic plastic analysis, idealization of welding that is methods to heat input simultaneously in all weld metal on the same welding direction is carried out on two weld joints(butt welding and fillet welding). Then, the accuracy of acquired results is investigated through the comparison of the high accuracy prediction results. The thermal conduction analysis results by idealization of welding, the temperature is raised accompany with beginning of heat input because all of weld metal is heated input at the same time. On the other side, the temperature witch predicted with high accuracy is raised at the moment heating source passes the measuring points. So, there is difference of time between idealization of welding and considering of moving heat source faithfully. However, temperature history by idealization of welding is well simulated a high accuracy prediction results.

High Quality Ortho-image Production Using the High Resolution DMCII Aerial Image (고해상도 DMCII 항공영상을 이용한 고품질 정사영상 제작)

  • Kim, Jong Nam;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.1
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    • pp.11-21
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    • 2015
  • An Ortho-image is the production of removed geometrical displacement, which is generated the aerial image distortion and the relief displacement, etc., using the DSM (Digital Surface Model). Accordingly, the resolution of raw image and the accuracy of DSM will has significant impacts on the ortho-image accuracy. Since the latest DMCII250 aerial camera delivers the high resolution images with five centimeters Ground Sampling Distance(GSD), it expects to generate the high density point clouds and the high quality ortho-images. Therefore, this research has planned for reviewing the potentiality and accuracy of high quality ortho-image production. Following to proceed the research, DSM has been produced through the high density point cloud extracted from DMCII250 aerial image to supply of high density DSM by creation of ortho-image. The research results has been identified that images with the DSM brought out higher degrees in positional accuracy and quality of ortho-image, compared with the ortho-image, produced from the existing digital terrain map or DSM data.

Analysis for Accuracy of High Resolution Satellite Data Using Simulation data (시뮬레이션 자료를 이용한 고해상도 인공위성자료의 정확도 분석)

  • Seo Doo-Chun;Lee Dong-Han;Park Su-Young;Song Jeong-Heon;Lim Hyo-Suk
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.255-258
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    • 2006
  • With the increasing availability of high-resolution satellite imagery, the demand for ortho-rectified products will also be growing. High-resolution of the imagery (up to 1m) the desired accuracy of the ortho-rectification is more sensitive to a number of factors. including satellite position, velocity, internal sensor error (specifically, misalignment. lens distortion, etc.). sensor modeling, relief displacement and matching error, etc. The main objective of this study is to analysis the accuracy of high resolution satellite data using simulation data.

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A Study on the Effected Factor for Vibration Criteria of Sensitive Equipment (정밀장비의 진동허용규제치에 미치는 인자에 관한 연구)

  • 이홍기;장강석;김두훈;김사수
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1998.04a
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    • pp.302-307
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    • 1998
  • In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a sub-micrometer. This equipment requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga and tera class semiconductor wafers. This high technology equipments require very strict environmental vibration standard, vibration criteria, in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be represented in the form of exactness and accuracy, because this is used as basic data for the design of building structure and structural dynamics of equipment. The study on the evaluation of the factors affecting the permissible vibration criteria is required to design the efficient isolation system of the semiconductor manufacturing of equipment. This paper deals with the properties of the effected factor for vibration criteria of high sensitive equipment.

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INITIAL GEOMETRIC ACCURACY OF KOMPSAT-2 HIGH RESOLUTION IMAGE

  • Seo, Doo-Chun;Lim, Hyo-Suk;Shin, Ji-Hyeon;Kim, Moon-Gyu
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.780-783
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    • 2006
  • The KOrea Multi-Purpose Satellite-2 (KOMPSAT-2) was launched in July 2006 and the main mission of the KOMPSAT-2 is a high resolution imaging for the cartography of Korea peninsula by utilizing Multi Spectral Camera (MSC) images. The camera resolutions are 1 m in panchromatic scene and 4 m in multi-spectral imaging. This paper provides an initial geometric accuracy assessment of the KOMPSAT-2 high resolution image without ground control points and briefly introduces the sensor model of KOMPSAT-2. Also investigated and evaluated the obtained 3-dimensional terrain information using the MSC pass image and scene images acquired from the KOMPSAT-2 satellite.

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A structural study on mold EMBO equipment to minimize the influence on the bottom dead center displacement of precision high-speed press (정밀고속 PRESS 하사점 변위량에 영향을 최소화 하는 금형 EMBO 장치에 관한 구조 연구)

  • Kim, Seung-Soo
    • Design & Manufacturing
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    • v.10 no.3
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    • pp.46-50
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    • 2016
  • Laminate products for motor core are developed with a structure in which the importance of quality level and clamping force is influenced by the recent performance and safety of the product. It has been confirmed that the accuracy of the mold is emphasized, and that the accuracy of the tightening force produced by the stacked product for the motor core is greatly influenced by the change in the bottom dead center displacement of the aged high speed press. The reason why setting the mold, and test the effect of bottom dead center of high speed press is to improve product pull force in embossing process at mold. We have applied the system to minimize the effect on the damping displacement under the dynamical degree of the equipment by applying the emboss complement device which can test the influence and complement in the process.

A Study on the Development of a High Speed Feeding Type Three-Dimensional Bending Machine (초고속 이송 방식 3차원 Bending Machine 개발에 관한 연구)

  • Lim, Sang-Heon;Lee, Choon-Man
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.11 s.176
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    • pp.91-98
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    • 2005
  • This study has been focused on the development of a high speed feeding type three-dimensional bending machine. It is designed for manufacture of copper pipe for heat exchangers. For the purpose of design of the machine, analysis of bending process, structural analysis and reliability evaluation of the machine by a laser interferometer are carried out. The analysis is carried out by FEM simulation using commercial softwares, DEFORM, MARC and CATIA V5. In addition, the machine has attained high accuracy and repeatability. In order to improve the accuracy of this machine, the maximum speed, positioning accuracy and repeatability of feed are measured by the laser interferometer. The final results of analysis are applied to the design of a high speed feeding type three-dimensional bending machine and the machine is successfully developed.

Measurement and Correction of PCB Alignment Error Using Two Cameras (2대의 카메라를 이용한 PCB의 위치 오차 측정 및 보정)

  • 김천환;신동원
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.302-302
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    • 2000
  • This paper presents the measurement and correction of PCB alignment errors for PCB-manufacturing machines. The conventional PCB-manufacturing machine doesn't have enough accuracy to accommodate the demand for high-resolution circuit pattern and high-density mounting capacity of electronic chips. It is because of alignment errors of PCB loaded to the PCB-manufacturing machine. Therefore, this study focuses on the development of the system which is able to measure and correct alignment errors whit high-accuracy. An automatic optical inspection part measures the PCB alignment error using two cameras, and the high-accuracy 3-axis stage makes correct of these error. The operating system is run in the environment of Window 98 (or NT). Finally we implemented this system to PCB screen printer and PCB exposure system.

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A Study on the Specification of Vibration Criteria of Sensitive Equipment (고정밀장비의 진동허용규제치 사양에 관한 연구)

  • 이홍기;박해동;김두훈;김사수
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.04a
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    • pp.362-369
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    • 1997
  • In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be expressed in the form of 'exactness' and 'accuracy', because this is made basic data in the use of building structure design. This paper made a study on the specification of high sensitive equipment and proposed a contents of the specification.

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