• 한국정밀공학회지
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• 제26권4호
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• pp.91-99
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• 2009

Because of both precise measurement and efficient quality control, coordinate measuring machines(CMMs) have been widely used in the industry. The purpose of this paper is to present a method to estimate the CMM measurement uncertainty using design of experiments. A factorial design is applied to carry out the performance test proposed by ISO 10360 and to investigate CMM measurement errors associated to orientation and length of the length bar. In order to assess the measurement uncertainty for the performance test, an analysis of the uncertainty components that make up the uncertainty budget has been carried out. The procedure for evaluating the uncertainty of it follows GUM ("Guide to the expression of uncertainty in measurement"). The results show that the proposed method is suitable to investigate CMM performance and determine the contribution of machine variables to measurement uncertainty.

• 한국정밀공학회지
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• 제14권11호
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• pp.118-125
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• 1997

Non-contacting optical microscopes are increasingly used in recent industrial applications of probes for coordinate measuring machines. They have been found more efficient than conventional touch trigger porbes with ball tips especially in inspecting small-sized objects. There are two major factors affecting measuring accuracy: (1) geometric relations between coordinate systems, (2) magnification ratios of a microscope. In order to determine the magnification ratios exactly, optical imaging of edge was theroretically analyzed and practically adopted to image processing for edge detection. In addition, this paper proposes a geometric calibration method to obtain exact coordinates of measured points from the relations between the machine coordinate system and the image. In the method, the error according to the squareness between the machine axises was also removed. The method was practically adopted to a real coordinate measuring machine. An ultraprecision measurement of 0.2 um uncertainty can be practically achieved.

• 한국안전학회지
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• 제18권4호
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• pp.23-27
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• 2003

To improve the road transportation safety, the road traffic data is monitored by applying an image detection system. The road traffic safety is analysed using image processing techniques. For more accurate measurement, the coordinate matching of real road data to image is one of the most essential parts of the image detection technique. The road image is skewed at the input screen, because the video camera is installed at the roadside. A fast and precise algorithm for the coordinate matching is developed to convert image coordinates into road coordinates.

• 한국정밀공학회지
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• 제21권11호
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• pp.99-109
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• 2004

This paper proposes precision evaluation method for the positioning error of three-DOF translational parallel mechanism. The proposed method uses conventional CMM as metrology equipment to measure the position of end-effector. In order to obtain accurate measurement data from CMM, the transform relationship between the coordinate system of the parallel mechanism and the CMM coordinate system must be identified. For this purpose, a new coordinate referencing (or coordinate system identification) technique is presented. By using this technique accurate coordinate transformation relationships are efficiently established. According to these coordinate transformation relationships, an equation to calculate error components at any arbitrary position of the end-effector is derived. In addition, mathematical fitting models to represent the position error components in the two-dimensional workspace of the parallel mechanism are also constructed based on response surface methodology. The proposed error evaluation method proves its effectiveness through the experimental results and its application to real three-DOF parallel mechanism.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.116-120
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• 1991

Technique of length measurement error is widely used in the accuracy assessment of CMMS(Coordinate measuring machines) and machine tools, as it is simple and direct measurement within the working volume of a machine. In this paper, a new method is proposed for the evaluation of the length measurement error in relation to the volumetric accuracy. lD, 2D, and 3D measuring lines are considered for recpective length measurement error: 1D, 2D, and 3D length measurement uncertainties are evaluated from volumetric accuracy. The relationship between the volumetric accuracy md length measurement error to is discussed. PC based system for length measurement error evaluation and simulation is developed.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.3-9
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• 2004

The machining parts must be produced within the specification of drawing and those will be able to meet function and efficiency. At that time. it is necessary not only precision machine or machining technique but also the measurement technique is very important. So. the improvement of precise measurement technique is to be joined together at once with improvement of product technique. Finally. he quality and value of the parts are decided by precision measurement. This paper aims to study on he measurement uncertainty when the machined parts are inspected with 3-dimensional coordinate measuring machine. The objectives are to remove an error of measurement and to improve quality and productivity of the mass products.

• 한국공작기계학회논문집
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• 제14권2호
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• pp.55-61
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• 2005

The machining Parts must be Produced within the specification of drawing and those will be able to meet faction and efficiency. At that time, it is very important not only precision machine and machining technique but also the measurement technique. So, the improvement of measurement technique is to be joined together at once with improvement of machining technique. Finally, the quality and value of the parts are decided by precision measurement. This paper aims to study on the measurement uncertainty when the machined parts are inspected with 3-dimensional coordinate measuring machine. The objectives remove an error of measurement and remove a quality of mass products.

• International Journal of Concrete Structures and Materials
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• 제10권2호
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• pp.189-203
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• 2016

This paper investigates on the use of advanced optical measurement methods, i.e. 3D coordinate measurement machines (3D CMM) and stereo-vision digital image correlation (3D DIC), for the mechanical analysis of shear deficient prestressed concrete members. Firstly, the experimental program is elaborated. Secondly, the working principle, experimental setup and corresponding accuracy and precision of the considered optical measurement techniques are reported. A novel way to apply synthesised strain sensor patterns for DIC is introduced. Thirdly, the experimental results are reported and an analysis is made of the structural behaviour based on the gathered experimental data. Both techniques yielded useful and complete data in comparison to traditional mechanical measurement techniques and allowed for the assessment of the mechanical behaviour of the reported test specimens. The identified structural behaviour presented in this paper can be used to optimize design procedure for shear-critical structural concrete members.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.14-15
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• 2019

In this paper, it was tried to prove the possibility and effect of coordinate measurement by using MEP layout equipment at the construction stage, and to propose a method to improve measurement accuracy during construction. For this study, the passenger terminal site, which is a long span structure, was selected and compared with three dimensional CAD drawings and construction measurement results using MEP layout equipment for the precise construction of long-span irregular curved roof layers. As a result, it was found that it is possible to construct three-dimensional curved roof layers using MEP layout equipment through measurement and analysis.

• 대한토목학회논문집
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• 제12권4호
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• pp.157-165
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• 1992

데오돌라이트를 이용한 정밀측량시스템인 IMS가 개발되어 기계구조물의 정밀측량에 사용되고 있다. CMM(Coordinate Measuring Machine)과 같은 종래의 기계적 정밀측정장비에 비하여 측량대상물의 크기와 모양에 거의 제한이 없으며, 대상물이 설치되어 있는 현장에서 측량을 실시할 수 있다는 장점이 있으며, 또한 자료의 실시간 표현이 가능하여 대상물에 대한 관측과 위치수정을 동시에 수행할 수 있다는 장점도 가지고 있다. 본 논문에서는 IMS의 구성과 기능에 관한 고찰과 더불어, 새로이 개발된 소프트웨어의 수학적 모델이 제시되었는데, 그 모델은 해석사진측량에서의 광속조정법을 IMS의 특수성에 맞게 변형한 형태이다. 관측에서의 단계별 진행방법이 설명되었고, 그 배경 및 해석사진측량 기법과의 차이에 대하여 논의되었다. 데오돌라이트 외부표정요소와 대상물 공간좌표의 초기치를 더욱 근사(近似)하게 계산할 수 있는 새로운 IMS Calibration의 방법도 제시되었다. 대상물 관측전에 광속조정접을 적용하여 데오돌라이트 외부표정요소와 대상물 공간좌표의 초기치를 산출하도록 하였으며, 측량작업이 완료된 후 광속조정법을 이용하여 결과치를 재보정할 수 있게 하였다.