• 한국CDE학회논문집
• /
• 제16권1호
• /
• pp.11-20
• /
• 2011

A structured beam laser is often used to scan object and make 3D model. Multiple cameras are inevitable to see occluded areas, which is the main reason of the high price of the scanner. In this paper, a low cost 3D foot scanner is developed using one camera and two mirrors. The camera and two mirrors are located below and above the foot, respectively. Occluded area, which is the top of the foot, is reflected by the mirrors. Then the camera measures 3D point data of the bottom and top of the foot at the same time. Then, the whole foot model is reconstructed after symmetrical transformation of the data reflected by mirrors. The reliability of the scan data depends on the accuracy of the parameters between the camera and the laser. A calibration method is also proposed and verified by experiments. The results of the experiments show that the worst errors of the system are 2 mm along x, y, and z directions.

• 한국의류학회지
• /
• 제47권1호
• /
• pp.137-151
• /
• 2023

Stationary 3D whole-body scanners generally require 5 to 20 seconds of scanning time and cannot effectively detect armpit and crotch areas. Therefore, this study aimed to analyze the accuracy of a photogrammetric technique using a multi-camera system. First, dimensional accuracy was analyzed using a mannequin scan, comparing the differences between the scan-derived measurements and the direct measurements, with an allowable tolerance of ISO 20685-1:2018. Only 2 of 59 measurement items (ankle height and upper arm circumference, specifically) exceeded the ISO 20685-1:2018 criteria. When compared with the results of the eight stationary whole-body scanners assessed by the literature, the photogrammetric technique was found to have the advantage of scanning the top of the head, armpit, and crotch areas clearly. Second, this study found the photogrammetric technique is suitable for obtaining the body scans because it can minimize the perform scanning, resulting in a reduction of measurement errors due to breathing and uncontrolled movements. The error rate of the photogrammetry method was much lower than that of stationary 3D whole-body scanners.

• Journal of the Korean Wood Science and Technology
• /
• 제52권3호
• /
• pp.276-288
• /
• 2024

This study was conducted to reproduce the woodworking process of Baekje wooden storage facilities. Green timber of Quercus spp. was processed using ancient woodworking tools, and the tool-trace formed in this process were compared with the tool-trace of actual excavated artifacts. In the tool-trace analysis, the length and shape of the tool-trace were objectively recorded using a 3D Scan, and that were difficult to confirm with photograph were confirmed through stereoscopic microscope. As a result, there were two types of adze's tool-trace. One of them is minute straight Blade-top trace line when trimming the wood surface and the other is Plucked trace that appear when strongly chop at the wood. When a chisel bat was not used, a long and wide continuous shape blade trace was produced. And when the chisel head was struck with the chisel bat, a straight blade-top trace was regularly observed. Saw-trace was identified in several layers with fine straight stripes. Through this, it was found that the tool-trace of the woodworking tools, which is estimated to have been used in each process, and the tool-trace remaining in the Baekje wooden storage facility coincide.

• 한국해양공학회지
• /
• 제9권2호
• /
• pp.83-88
• /
• 1995

In this paper, the solid modeller suitable for PC was developed for Top-down 3-D representation and analysis of fixed offshore structures. Also solid modelling and hidden line removal were conducted in order to visualize the offshore structures based on the scan line z-buffer algorithm.

• 대한치과의사협회지
• /
• 제38권10호통권377호
• /
• pp.956-961
• /
• 2000

• 대한임상전기생리학회지
• /
• 제3권1호
• /
• pp.61-70
• /
• 2005

The purpose of study correlation between 3D-surface topography and Cobb angle in scoliotic patients. It would be recognizing possibility of clinical application with 3D-surface topography with scoliosis assessment and correlation analysis of obtained Cobb angle through measured results of surface topography and took X-ray of subjects with scoliosis, which used to 3D-surface topography of laser scan method. A scoliosis subjects 16(males 4, females 12) agreed for study's purport volunteer our study that diagnose the scoliosis through 3D-surface topography and X-ray. The results were as follow: It was shown that the relation of Cobb angle of scoliosis and itemized 3D-surface topography measurement in horizontal view(p<0.01). top difference of cervicothoracic and lumbar in anterior-posterior view(p<0.05), the top difference of thoracic, thoracolumbar(p<0.01). These results suggest that an itemized 3D-surface topography measurement was highly correlated with Cobb angle. It would be a useful diagnosis method and assessment of physical therapy plan.

• 한국멀티미디어학회논문지
• /
• 제15권7호
• /
• pp.941-950
• /
• 2012

본 연구에서는 PC상에서 인체 3차원 데이터에 상하의 의류를 중첩 착의하는 가상 착의 시스템을 소개한다. 이를 위하여, 레이저 스캔 방식으로 얻은 인체 3차원 데이터와 의류 앞뒷면의 모습을 촬영하여 얻은 의류 디지털 데이터를 이용한다. 2차원의 앞뒷면 의류 디지털 데이터에는 의류 소재 내 질점 간의 장력이 반영되었고, 인체 데이터에의 착의 과정에는 마찰력과 중력을 적용해 주었다. 하의 착용 시에는 마찰력과 중력에 추가적으로 혁대 개념을 도입하여 흘러내리는 의류를 고정하였고, 하의를 착의한 인체데이터위에 상의를 착의하는 중첩 착의 방법을 제시하였다. 본 시스템이 지닌 장점은 복잡한 패턴을 이용하여 착의하는 다른 연구와 달리, 의류의 앞뒷면만을 이용하여 착의하면서도 현실감은 뒤지지 않는다는 것에 있다. 현재 의류전자상거래 시 의류의 앞뒷면만을 전시하여 판매하는 방법과 유사한 방식으로 온라인 판매가 이루어지나, 착의 모습을 제공할 수 없는 기존 방식과 달리 3차원의 착의 모습까지 제공하게 되어, 의류 판매의 방식을 바꾸게 할 것으로 기대한다.

• 한국산학기술학회논문지
• /
• 제21권12호
• /
• pp.107-114
• /
• 2020

기계, 디자인, 중공업 분야에서 많이 사용되어오던 역설계 기법이 최근 건설 산업분야에 BIM(Building Information Modeling) 기반 역설계 기법인 Scan-to-BIM 기술로 적극적으로 도입되기 시작하였으며, 그동안 비효율적인 부분들을 개선하기 위한 알고리즘, 시스템, 장비 등의 개발이 이루어지면서 기술의 확장성이 더욱 커지고 있다. 본 연구에서는 객관적인 자료에 근거한 특허 분석을 통하여 한국, 미국, 유럽, 일본의 Scan-to-BIM 관련 기술 동향을 파악하여 한국 Scan-to-BIM 기술의 올바른 방향을 모색하고자 한다. 건설 산업기술 특허분석관련 선행 연구 분석, Scan-to-BIM 기술에 대한 이론적 고찰과 관련 선행연구 고찰, WIPSON 특허검색시스템을 사용한 한국, 미국, 유럽, 일본 네 국가의 관련 기술에 대한 공개된 특허 문헌을 검색하여 정보를 수집, 검증과정 및 유효 특허 추출이 이루어졌으며, 도출된 유효 특허 데이터를 이용하여 특허출원 연도별 동향, 국가별 동향, 그리고 국제특허분류(IPC: International Patent Classification) 코드를 통한 기술별 동향, 상위 20위 주요출원인 및 출원 주체 종류, 패밀리 특허 동향 등을 분석하였다.

• 대한치과보철학회지
• /
• 제61권4호
• /
• pp.367-378
• /
• 2023

최근 CAD-CAM (computer-aided design-computer-aided manufacturing) 기술 및 3D 프린팅 기술의 발전과 함께 다양한 디지털 기법들의 도입으로 top-down 방식의 최종 보철 수복의 정확성과 효율성이 증대되고 있다. 본 증례는 전후 엇갈린 교합을 가진 환자에서 총 9개의 상하악 구치부 임플란트 식립을 통해 안정적인 교합 지지를 얻으면서 잔존 치조골의 고도 흡수 경향을 보인 상악 전치부 무치악 부위는 케네디 4급 임플란트 보조 국소의치로 수복함으로써 연조직의 심미성을 회복하였다. 전산화단층촬영 가이드 수술로 계획된 위치에 임플란트를 식립하고, 이중 스캔 기법으로 임시 수복 단계에서 안정화된 교합을 최종 보철물에 반영하며, 코핑과 프레임워크를 금속 3D 프린팅으로 제작하여 효율적이며 예측 가능한 top-down 방식의 전악 구강 수복을 달성하였기에 이를 보고하고자 한다.

• 복식문화연구
• /
• 제19권6호
• /
• pp.1359-1371
• /
• 2011

The purpose of this paper is to compare two avatars made using direct and manual methods and to evaluate the fit and appearance of two virtual garments on the direct and manual avatars. In this study, two subjects were measured by $[TC]^2$ body scanner and the avatars and virtual garments were created by OptiTex software. The direct avatar was made by the direct importation of 3D body scan data and the manual avatar was made by manual input from extracted body measurement. Two virtual garments in a tank-top were evaluated by distance, transparency, and stretch maps. In the results of comparing difference of the direct and manual avatars, the bust and back of the manual avatar are protruded slightly more than that of the direct avatar and the manual avatar is slightly larger dimensions at the bust, waist, abdomen, and hip area in the side view in case of subject 1 and 2. In the results of comparing difference of the fit and appearance of two virtual garments on the direct and manual avatars, in case of subject 1 and 2, the back of the virtual garment on the manual avatar are protruded more than that of the direct avatar. Also, the ease in the bust area of the virtual garment on the manual avatar with a projected bust area was smaller than that of the virtual garment on the direct avatar and the stretch of that of the manual avatar was also high in the bust area. The results of this study are expected to be used as basic information in the apparel industry using virtual try-on technology.