• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.89.1-89
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• 2001

Measurement of complex surfaces without touching is desirable in several fields. This arises mainly for measurement of complex surfaces including those surfaces that deform during touch. Our research presented in this paper describes the use of a 3D digitizer for scanning 3D objects. The use of such a device, in addition to proper calibration, requires proper scaling in all three dimensions. We propose measurement techniques to measure various aspects of the surface circumference, area and volume. We also present experiments from using a 3D Minolta digitizer for measuring 3D human heads.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권1호
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• pp.17-25
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• 2012

Purpose: Recently, a three dimensional approach to hard and soft tissues of the maxillofacial area has been widely used. This study was to evaluate the reproducibility and accuracy of a stereocamera compared to actual measurement methods using a digital caliper and digitizer. Methods: The stereoscopies of 7 head dummies with different sizes and shapes were obtained using a Di3D system (Dimensional Imaging, Glasgow, UK) after marking reference points on facial areas. From the obtained stereoscopy, 10 measurements representing the width, height and depth of each of the facial sections of the dummy were measured twice using a three dimensional reverse engineering software program (RapidForm$^{TM}$ 2006, Inus, Seoul, Korea). The x, y, and z coordinates of each of the three dimensional measurements were obtained and distances between two points were calculated. All procedures were repeated twice. The actual measurement method was performed twice, directly on dummies, using a digital caliper and values were compared with the previously determined values. Results: The results were as follows. In the ANOVA analysis, there were no significant statistical differences among the three measurement methods. In the Bonferroni analysis, with adjustments applied for multiple comparisons, there was no difference between actual measurement methods using a digitizer and a digital caliper. However, there was some difference between using a stereocamera and actual measurement methods using a digitizer and a digital caliper in values of $Ex_{Rt}-Ex_{Lt}$, $En_{Rt}-En_{Lt}$, $Ala_{Rt}-Ala_{Lt}$, $Ch_{Rt}-Ch_{Lt}$, G-Pg', $Ala_{Rt}$-Prn, $Ala_{Rt}$-Prn. The mean value for technical error in measurement (TEM) in Di3D (0.98 mm) was slightly higher than for a digital caliper (0.17 mm) and a digitizer (0.30 mm). In an intraclass correlation coefficient (ICC) there were no significant differences among the three measurement methods, but the Di3D system with the stereocamera showed relatively lower reproducibility compared to actual measurement methods using a digitizer and a digital caliper. Conclusion: These results indicate that some complementary measures may be needed to improve accuracy and reproducibility in the Di3D system with stereocamera.

• 보존과학회지
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• 제33권1호
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• pp.11-16
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• 2017

본 연구에서는 일본 목판 인쇄에 사용된 판목 구조의 과학적 조사를 실시하였다. 또한 판목이 입체적인 구조의 유물이라는 사실에 주목하여 2차원보다 3차원의 조사가 유효하다고 판단, 판목 연구에서 첫 사례가 되는 3D CT스캐너, 고화질 3차원 디지타이저를 이용한 조사를 진행하였다. 3D CT스캐너를 이용한 조사 결과, 판목의 단면 정보로부터 사용된 나뭇결과 내부 구조의 확인 및 계측, 생존 중인 벌레의 존재를 밝혀내었다. 3차원 디지타이저를 이용한 조사에서는 0.02 mm 단위의 관찰이 가능하여 기존의 현미경으로는 조사가 곤란했던 판목의 표면 정보를 상세히 관찰할 수 있었다.

• International Journal of Precision Engineering and Manufacturing
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• 제6권4호
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• pp.60-66
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• 2005

In this paper, we propose the basic measurement method of a 3D digitizer using a CCD camera in detail. In the localization measurement with a CCD camera, the effect of the background light and the sensitivity consideration are always problems in realizing a high precision. In this research, a new measurement principle is proposed in which the pulse compression technique known in radar is used to eliminate the effect of background light even under a low intensity light source, and the coordinate values on the CCD camera image plane are determined accurately. From the quantitative evaluation of the S/N ratio improvement and the fundamental experiment, it is verified that a substantial improvement in the S/N ratio is realized for both the background noise and the pixel noise and that a resolution of less than the pixel is sufficiently possible.

• 한국정밀공학회지
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• 제16권4호통권97호
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• pp.102-109
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• 1999

Reverse engineering is a technique that helps designers to quickly generate computer interpretable data from existing physical objects. It can be used for generating CAD data from a mechanical part of high precision, or generating computer animation characters from physical mock-ups. We developed a low precision reverse engineering system that is composed of surface/solid generation software and a contact type commercial 3D digitizer. A unique point sampling procedure has been devised to easily form solid topology from the sampled data. It was also shown that STL data for rapid prototyping was successfully generated from the solid.

• 대한치과보철학회지
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• 제43권4호
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• pp.453-465
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• 2005

Purpose: This study was performed to measure the accuracy of adjustable dental impression trays by a scanning laser three-dimensional digitizer. Materials and methods: The metal stock, individual, and adjustable stock trays were used for 60 stone casts(10 casts each) duplicated a resin master model of mandible and maxilla. The type IV dental stone was poured in a vinyl polysiloxane impressions and allowed to set for one hour. The master model and the duplicated casts were digitized using an optical digitizer. The distance between the reference points were measured and analyzed on the graphic image of 3-D graphic software(CATIA version 5.0). The statistical significance of the differences between the groups was determined by a two-way ANOVA. Results : There were no significant differences between the accuracies of the adjustable stock tray and the master model except only anterior arch width on the upper arch and the diagonal arch length and arch length on one side of the lower arch. Conclusion: The adjustable stock trays showed clinically acceptable accuracies of the study cast produced by them.

• 구강회복응용과학지
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• 제22권4호
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• pp.317-328
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• 2006

Purpose: This study was performed to measure the accuracy of adjustable dental impression trays by a scanning laser three-dimensional digitizer. Materials and Methods: Metal stock tray and adjustable stock trays were used for 40 stone casts(10 casts each) duplicated a resin master model of mandible and maxilla. The type IV dental stone was poured in a allginate impressions and allowed to set for one hour. The casts were digitized using an optical digitizer. The distance between the reference points were measured and analyzed on the graphic image of 3-D graphic software (CATIA version 5.0). The statistical significance of the differences between the groups was determined by a two-way ANOVA. Results: There were no significant differences between the accuracies of the adjustable stock tray and the master model except anterior arch width of the upper arch and the diagonal arch length and arch length(one side) of the lower arch. Conclusion: The adjustable stock trays showed clinically acceptable accuracies of the study casts produced by them.

• 한국디지털건축인테리어학회논문집
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• 제12권1호
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• pp.25-33
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• 2012

Ever since the local interior and architecture design industry adopted Digital fabrication modeling tool for its design operation in early 1990's, working environment has been changing. The Purpose of study is to analyze the digital Architecture fabrication modeling for digital design education in academy course. Digital Design Tools, Digital Space and Form, Digital Materiality and Digital Production. The Digital fabrication modeling is and important role in a traditional design process and digital design process. It is comprised of digital input devices(3D digitizer, 3D design tools) and digital output devices(cutting plotters, laser cut, CNC machines, 3D printers). Digital input devices can be shift a traditional design process to digital design process. Digital output devices are the principle of digital fabrication by CAD/CAM. Also, the result of this study provide the fundamental data for physical resources and digital design curriculum in KAAB.

• 한국의학물리학회지:의학물리
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• 제3권1호
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• pp.63-69
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• 1992

최근 3차원적인 영상 데이타 및 방사선량 분포에 대한 정보를 필요로하는 뇌정위적 방사선 치료계획이 절실히 요구되고 있다. 본 연구의 목적은 personal computer를 이용하여 3차원적인 환자영상 데이터 및 선량분포를 함께 처리할 수 있는 치료계획 시스템을 개발하는 데 있다. 본 연구를 위한 처리 과정은 크게 3단계로 나누어 수행된다. 첫째, 환자영상 데이타 입력과정으로서, CT, MRI 등 단층촬영영상을 on-line 및 digitizer 방식을 통하여 personal computer에 입력시킨다 병소위치 및 모양도 Angio 및 CT localization 방법을 이용하여 함께 입력시킨다. 둘째, 선량계산 단계로서, stereotactic frame 좌표로 변환된 영상내에서 선량 분포를 계산하고 환자영상 데이타 및 치료기의 조사조건등에 따라 최적 선량분포를 얻는다. 셋째, display 과정으로서, 임의의 단층영상 및 재구성 영상내에서 환자영상과 방사선량에 대한 영상을 합성하여 computer monitor를 통하여 단일 영상내에 동시에 묘출할 수 있도록 처리한다. 본 연구의 치료계획 시스템을 응용한 바 치료계획을 신속하고 정확하게 처리할 수 있었으며, Angio, CT 혹은 MRI와 같은 여러형태의 영상내에서 선량분포를 동시에 묘출함으로써 능률적인 치료계획을 세울 수 있었다. 이와같은 치료계획의 자동화 시스템은 지금까지 어려웠던 3차원적인 뇌정위적 방사선치료계획을 가능케 하며, 추후 beam's eye view나 CT simulation을 통한 일반적인 3차원 방사선 치료계획에도 크게 이바지할 것으로 기대된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.79.4-79
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• 2002

Our goal is the development of a system that estimates the location of interested point in a room with accuracy and low cost. Non-contacting position estimating method is widely used in various areas. Among these methods, acoustic signal-based method is the cheapest and provides reasonably accurate estimation as a result of many research efforts. Most of the acoustic-signal-based three-dimensional location estimators such as 3D sonic digitizer are using the ultrasound, and are organized with two procedures; time-of-flight (TOF) estimation and localization estimation. Since the errors in estimating the TOF could be accumulated with that of localization estimate, accuracy of TOF estimate is as...