광섬유센서에 의한 간이 비접촉 표면조도 측정기의 개발

홍준희 대한공업교육학회 2009 대한공업교육학회지 Vol.34 No.2

The purpose of this study was to develop the handy non-contact measurement device of the surface roughness by using the optical fiber sensor. The advantages of fiber optic sensors are high-speed responsibility, non-effect of the magnetic, convenience of the product and high precision. The measurement theory for surface roughness of optical fiber sensor is one to one correspondence between the reflected light intensity based on the surface roughness of the object and the measurement value of previously known for surface roughness. The reflected light intensity was determined using the distance to the surface from the sensor probe and the limit reflection angle based on the surface roughness. Therefore, in this study, the sensor probe was produced for determining the value of surface roughness only using the limit reflection angle based on the surface roughness with the fixed distance from the surface. A prototype measurement system was composed of a transmitting part, a receiving part and a signal processing circuit. The materials of standard measurement which was used in this experiment were SM45C, STS303 and Al60. According to the results of this study, approximation surface roughness formulas which was deduced from the correlation of between the standard surface roughness and the sensing output were verified that they were effect against the surface roughness measurement value of the option sample. And handy optical fiber surface roughness measurement device which was produced by an order was verified that it was effect for measuring of the precision surface roughness. 본 연구는 광섬유센서를 이용하여 표면조도의 간이 비접촉 측정기를 개발하 는데 목적이 있다. 광섬유 센서의 장점은 우수한 고속 응답성, 자기의 무영향, 제작의 편이성 이다. 광섬유센서 표면조도 측정 원리는 측정물의 표면조도에 따라 반사되는 광의 세기와 기지의 표면조도 값을 일대일 대응시키는 것이다. 반사광의 세기는 센 서 프로브로부터 표면까지의 거리와 표면조도에 따른 반사한계각에 따라 결정 되는데 본 연구에서는 표면까지의 거리를 일정하게 하여 표면조도에 따른 반 사한계각만을 가지고 표면조도가 결정되도록 측정 프로브를 제작하였다. 측정 시스템은 발광부, 수광부과 신호처리부로 구성되었다. 이 실험에서 사 용된 표준 측정 재료는 SM45C, STS303과 Al60이었다. 연구결과 첫째, 재료에 따른 표면조도와 센서출력의 상관관계로부터 근사표 면조도식을 도출하고 임의 가공된 시료의 표면조도 측정을 통해 근사표면조도 식이 유효함을 입증하였다. 둘째, 실제 제작한 간이 광섬유센서 표면조도 측정 기가 유용함을 입증하였다.

토사비탈면 붕괴에 대한 계측관리기준 제안: 지표 경사를 중심으로

최선규,정민수,석재욱,정향선,송효성 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.7

This research studied slope behavior and the development of measurement management criteria(MMC) for soil slope failure based on surface inclination by conducting a slope failure experiment with surface inclination measurement. In particular, a real scale steep-slope failure simulator was used in the slope failure experiment, and the displacement behaviors were measured and analyzed using a digital camera, displacement measurement, and inclination measurement to develop the MMC. Specifically, the displacement and inclination behaviors followed a polynomial model because two methods could measure the surface behavior of a slope. In addition, the graded MMC determined the 'surface inclination velocity' with the same method used for the MMC from surface displacement. Additionally, four types of MMC were determined for 'Watch-Starting point when value is detected', 'Caution-Starting point of constant velocity', 'Warning-End point of constant velocity', and 'Alert-End point of acceleration'. Based on the results of the research, four graded MMC results were obtained for 'Watch-Starting point when value is detected', 'Caution-0.04°/min', 'Warning-0.22°/min', and 'Alert-1.74°/min'. Also, each determined MMC exhibited reliability from the other slope failure experiment with different soils and a comparison with the corresponding MMC from surface displacement. 본 논문은 지표 경사계를 설치한 비탈면 붕괴실험을 통해 지표 경사 기반의 비탈면 거동 분석 및 지표 경사 기반의 계측관리기준 개발연구를 수행하였다. 지표 경사 기반 계측관리기준 개발을 위해 실규모 급경사지 붕괴 시뮬레이터를 활용하여 비탈면 붕괴를 유도하였으며, 붕괴과정 동안의 지표 거동을 영상촬영, 지표 변위계 그리고 지표 경사계를 이용하여 측정 및 분석하였다. 분석 결과 지표 변위 거동과 지표 경사 거동 모두 다항형의 거동을 보이는 것으로 확인되었으며, 이는 두 계측기 모두 직접적인 지표의 변화를 측정하는 방법이기 때문으로 판단된다. 따라서, 지표 경사의 계측관리기준은 다항형 모델을 기반으로 설정하였으며, 계측관리기준의 단위는 ‘지표 경사속도’로 설정하였다. 단계별 관리기준은 ‘관심단계-계측시점’, ‘주의단계-등속의 시점’, ‘경계단계-등속의 종점’, ‘심각단계-과속의 종점’인 4단계로 설정하였다. 데이터 분석을 통한 최종 산정한 계측기준은 ‘관심단계-계측시점’, ‘주의단계-0.04°/min’, ‘경계단계-0.22°/min’, ‘심각단계-1.74°/min’로 제안하였다. 본 연구에서 제안한 단계별 계측관리기준은 추가적인 실증실험을 통한 데이터 분석 및 지표 변위 기반의 계측관리기준과의 계측 경보 발령 비교를 통해 신뢰성을 검증하였다.

Design and Construction of a Surface Encoder with Dual Sine-Grids

Akihide Kimura,Wei Gao,Satoshi Kiyono 한국정밀공학회 2007 International Journal of Precision Engineering and Vol.8 No.3

This paper describes a second-generation dual sine-grid surface encoder for 2-D position measurements. The surface encoder consisted of a 2-D grid with a 2-D sinusoidal pattern on its surface, and a 2-D angle sensor that detected the 2-D profile of the surface grid. The 2-D angle sensor design of previously developed first-generation surface encoders was based on geometric optics. To improve the resolution of the surface encoder, we fabricated a 2-D sine-grid with a pitch of 1 0 ㎛n. We also established a new optical model for the second-generation surface encoder that utilizes diffraction and interference to generate its measured values. The 2-D sine-grid was fabricated on a workpiece by an ultra precision lathe with the assistance of a fast tool servo. We then performed a UV-casting process to imprint the sine-grid on a transparent plastic film and constructed an experimental setup to realize the second-generation surface encoder. We conducted tests that demonstrated the feasibility of the proposed surface encoder model.

연마 다듬질 가공면의 표면 미세형상 평가에 관한 연구

조남규,김현국,권기환,한창수,안유민,이성환,박균명 한국공작기계학회 2000 한국공작기계학회 추계학술대회논문집 Vol.2000 No.-

This paper describes the statistical analysis techniques for the surface roughness assessment of polished surfaces. In experiments, the polishing process of the sample surfaces which are manufactured by ball end mill is consist of two steps; the cusp removal process and the surface finishing process. For the cusp removal process, the criterion of cusp removal was established from the power spectrum analysis to assess the change of the cusp removal rate. For the finishing process, the surface was polished by the rotational CBN tool and vibration wood tool. And the surface quality of polished surface was assessed using the functional parameters based on the statistical values of surface profiles. Consequently, the surface finish performance of the polished surface using the vibration wood tool was improved.

Design and Construction of a Surface Encoder with Dual Sine-Grids

Kimura, Akihide,Gao, Wei,Kiyono, Satoshi Korean Society for Precision Engineering 2007 International Journal of Precision Engineering and Vol.8 No.2

This paper describes a second-generation dual sine-grid surface encoder for 2-D position measurements. The surface encoder consisted of a 2-D grid with a 2-D sinusoidal pattern on its surface, and a 2-D angle sensor that detected the 2-D profile of the surface grid The 2-D angle sensor design of previously developed first-generation surface encoders was based on geometric optics. To improve the resolution of the surface encoder, we fabricated a 2-D sine-grid with a pitch of $10{\mu}m$. We also established a new optical model for the second-generation surface encoder that utilizes diffraction and interference to generate its measured values. The 2-D sine-grid was fabricated on a workpiece by an ultra precision lathe with the assistance of a fast tool servo. We then performed a UV-casting process to imprint the sine-grid on a transparent plastic film and constructed an experimental setup to realize the second-generation surface encoder. We conducted tests that demonstrated the feasibility of the proposed surface encoder model.

Development of a feature-recognition and measurement path generation system based on NURBS surfaces for 5-axis on-machine measurement

여인웅,송인호,천상욱,양정삼 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.7

On-machine measurement (OMM), which is used to measure the machined surfaces of a workpiece during or after the machining of the workpiece, enables direct measurement within the workspace without moving the workpiece. However, although the threedimensional geometric shape created by computer-aided design systems include various features, because such features are converted into non-uniform rational B-spline (NURBS) surfaces during OMM, measurement deviation occurs between a feature and its corresponding NURBS surface. In this paper, we suggest a method to generate the measurement path for 5-axis OMM in a way that recognizes the features necessary for measurement from NURBS surfaces whose feature data set was removed during the conversion processes. To verify the reliability of the measurement path generation system named OMV+, which was developed using the above method, we carried out an experiment to compare the measurement path that defines the measuring point on the feature and the path that defines the measuring point on the NURBS surface with the measured result using the touch probe on the machined workpiece.

선레이저 기반 이동체용 3차원 노면 모니터링 시스템 구현

최승호,김서연,김태식,민홍,정영훈,정진만 한국인터넷방송통신학회 2020 한국인터넷방송통신학회 논문지 Vol.20 No.6

노면측정은 노면 관리에서 노면의 평탄화된 정도 및 변위를 정량화하는 필수적인 과정이다. 보다 안전한 노면 관리 및 신속한 유지보수를 위해 이동체에서의 정밀한 노면 측정은 매우 중요하다. 본 논문에서는 이동체에서 측정가능 한 정밀 노면측정 시스템을 제안한다. 제안 노면측정 시스템은 고성능의 선레이저 센서를 사용하여 노면 표면의 정밀한 측정을 지원한다. 또한 RTK로 부터 획득한 위치 데이터를 정합하여 종/횡방향 프로파일 측정이 가능하고 속도기반 적응 적인 갱신 알고리즘을 통해 실시간적인 모니터링이 가능하다. 제안 시스템을 평가하기 위하여 Gocator 선레이저 센서, MRP 모듈, 및 NVIDIA Xavier 프로세서를 시험용 이동체에 탑재하여 노면에서 시험하였다. 시험 결과 MSE(mean square error) 기준 정확한 프로파일 측정이 가능함을 보인다. 제안 시스템은 도로의 상태 평가뿐 만 아니라 인접 지반 의 영향도 평가에 활용될 수 있다. Road surface measurement is an essential process for quantifying the degree and displacement of roughness in road surface management. For safer road surface management and quick maintenance, it is important to accurately measure the road surface while mounted on a vehicle. In this paper, we propose a sophisticated road surface measurement system that can be measured on a moving vehicle. The proposed road surface measurement system supports more accurate measurement of the road surface by using a high-performance line laser sensor. It is also possible to measure the transverse and longitudinal profile by matching the position information acquired from the RTK, and the velocity adaptive update algorithm allows a manager to monitor in a real-time manner. In order to evaluate the proposed system, the Gocator laser sensor, MRP module, and NVIDIA Xavier processor were mounted on a test mobile and tested on the road surface. Our evaluation results demonstrate that our system measures accurate profile base on the MSE. Our proposed system can be used not only for evaluating the condition of roads but also for evaluating the impact of adjacent excavation.

간섭계에 있어서의 계통 오차의 자율 교정 알고리즘

후지모토 이쿠마츠(Ikumatsu Fujimoto),이태용(Lee Taeyong) Korean Society for Precision Engineering 2005 한국정밀공학회지 Vol.22 No.5

When an almost flat surface under test is measured by an interferometer, the measurement result is largely influenced by systematic errors that include geometrical errors of a reference flat surface. To determine the systematic errors of the interferometer by the conventional method that is called the three flat method, we must take the reference flat surface out from the interferometer and measure it. Because of difficulties to set the reference flat surface to the interferometer exactly and quickly, this method is not practical. On the other hand, the method that measures a surface under test with some shifts in the direction being perpendicular to the optical axis of the interferometer is studied. However, the parasitic pitching, rolling and up-down movement caused by the above shifts brings serious error to the measurement result, and the algorithm by which the influences can be eliminated is not still established. In this paper, we propose the self-calibration algorithm for determining the systematic errors that include geometrical errors of a reference flat surface by several rotation shifts and a linear shift of general surface under test, and verify by a numerical experiment that this algorithm is useful for determining the systematic errors.

평면도형의 둘레와 넓이, 입체도형의 겉넓이와 부피에 대한 초등학교 6학년 학생들의 수행 능력 조사

임영빈,임예은,김수미 한국수학교육학회 2019 수학교육 Vol.58 No.2

Among the measurement attributes included in the elementary school mathematics curriculum, perimeter, area, volume and surface area are intensively covered in fifth and sixth graders. However, not much is known about the level of student performance and difficulties in this area. The purpose of this study is to examine the understanding and performance of sixth-grade elementary school students on some ideas of measurement and ultimately to give some suggestions for teaching measurement and the development of mathematics textbooks. For this, diagnosis questions were developed in relation to the following parts: measurement of perimeter and area of plane figure, measurement of surface area and volume of solid figure, and the relationships between perimeter and area, and the relationships between surface area and volume. The performances of 95 sixth graders were analyzed for this study. The results showed children's low performance in the measurement area, especially measurement of perimeter and surface area, and relationship of the measurement concepts. Finally, we proposed the introduction order of the measurement concepts and what should be put more emphasis on teaching measurement. Specifically, it suggested that we consider placing a less demanding concept first, such as the area and volume, and dealing more heavily with burdensome tasks such as the perimeter and surface area. 초등학교 교육과정에 포함된 측정 속성 가운데 둘레와 넓이, 겉넓이와 부피는 5, 6학년에서 집중적으로 다루어진다. 그러나 이 영역에서 학생들의 수행능력이 어느 정도가 되며 어떤 문제가 있는지에 대해서는 알려진 바가 많지 않다. 이 연구는 평면도형의 둘레와 넓이, 입체도형의 겉넓이와 부피에 대한 초등학교 6학년 학생들의 이해 정도를 진단하고, 각 요소별 수행 능력을 비교 분석하여 차후 수학 교과서 개발 및 측정 영역 지도를 위한 시사점을 도출하고자 하였다. 이를 위해 둘레, 넓이, 겉넓이, 부피, 둘레와 넓이의 관계, 겉넓이와 부피의 관계에 관련된 문항을 구성하여 6학년 학생 95명을 대상으로 수행 능력을 분석하였다. 분석결과 초등학교 6학년들의 수행능력이 둘레, 겉넓이, 둘레와 넓이의 관계, 겉넓이와 부피의 관계 영역에서 특히 낮은 것으로 드러났다. 이러한 연구 결과를 바탕으로 둘레와 넓이, 겉넓이와 부피 개념의 도입 순서와 지도 방법, 지도 순서 등에 대한 몇 가지 아이디어를 제안하였다.

표면파 측정을 통한 콘크리트 슬래브의 표면균열 깊이 측정

기성훈 한국구조물진단유지관리공학회 2015 한국구조물진단유지관리공학회 논문집 Vol.19 No.3

본 논문에서는 비접촉 표면파 측정을 이용하여 콘크리트 슬래브에 발생한 표면균열의 깊이를 측정하기 위한 비파괴 검사법을 연구하였 다. 이를 위하여 표면파 측정, 해석 및 균열 깊이 평가의 과정을 포함한 새로운 측정모델을 제안하였다. 먼저, 3차원 유한요소해석 모델을 이용하여 표면파의 에너지와 콘크리트 균열의 깊이의 상관관계를 표현하는 표면파 전달함수를 구하였다. 제안된 측정모델은 실험을 통하여 증명하였다. 한 쌍의 비접촉 센서를 이용하여 깊이 0~100mm의 10개의 표면균열을 포함한 콘크리트 슬래브 (1500×1500×180mm3)을 통 과하여 전달되는 표면파를 측정하였다. 측정모델은 콘크리트 균열 깊이에 대하여 약 최대 10%의 오차를 보이며 실제 깊이를 예측하는 것 으로 나타났다. 비접촉 표면파 측정을 통하여 얻은 결과는 기존의 TOFD에 바탕을 둔 초음파법에서 얻은 결과보다 향상된 정확도를 보이 는 것으로 나타났다. 특히 비접촉 센서의 특성상 매우 향상된 측정 속도 및 측정값의 일관성을 얻을 수 있었다. 본 연구에서는 모델의 실제 구조물에 적용성에 관한 토의를 포함하고 있다. Non-contact surface wave transmission (SWT) measurements are used to evaluate the depth of a surface-breaking crack in concrete slabs. The author propose a measurement model that includes an appropriate configuration of the source and receivers, and a transmission function for the given configuration. A series of numerical simulations using a 3D finite element model is used to obtain the transmission function. Then, validity of a proposed model is verified through experimental studies. Two air-coupled sensors are used to measured surface waves across surface-breaking cracks with varying depths from 0mm to 100mm with intervals of 10mm in a concrete slab (1500×1500×180mm3) in laboratory. As a result, the proposed method is demonstrated as to be effective for charactering the depth of a surface-breaking crack in concrete bridge deck with an average error of 10%. A discussion on practical applications of the proposed method is also included in this article.