Earticle

효과적인 산림경영계획 수립을 위해서는 수고, 흉고직경 등 수목관리정보에 대한 조사가 필요하다. 하지만 기존 의 산림조사 방법의 효율성을 향상시키기 위한 데이터 취득 기술의 융복합 및 적용에 대한 연구는 부족한 실정이다. 이에 본 연구에서는 3D 스캐너를 통해 취득되는 포인트클라우드 데이터를 활용하여 수목관리정보를 구축하고 분석하 였다. 고정형 및 이동형 3D 스캐너를 이용하여 연구대상지에 대한 데이터를 취득하였으며, 작업시간 비교를 통해 이동 형 3D 스캐너의 효율성을 제시하였다. 또한 포인트클라우드 데이터를 이용한 식생의 객체별 분류를 수행하고, 흉고직경 및 수고에 대한 정보를 구축함으로써 객체 관리가 가능한 수목관리정보를 구축하였다. 기존의 측정 방법과 비교한 정확 도 평가 결과 수고는 0.02-0.09m, 흉고직경은 0.01-0.04m의 차이를 나타내었다. 향후 추가적인 연구를 통해 객체별 식생의 위치와 수관에 대한 정보를 구축한다면 산림관리정보 구축 관련 업무 효율성 증가에 기여할 것이다.

In order to establish an effective forest management plan, it is necessary to investigate tree management information such as tree height and DBH(Diameter at breast height). However, research on convergence and application of data acquisition technology to improve the efficiency of existing forest survey methods is insufficient. Therefore, in this study, tree management information was constructed and analyzed using point cloud data acquired through a 3D scanner. Data on the study site was acquired using fixed and mobile 3D scanners, and the efficiency of the mobile 3D scanner was presented through comparison of working hours. In addition, tree management information for object management was constructed by classifying vegetation by object using point cloud data, and by constructing information on chest height diameter and height. As a result of the accuracy evaluation compared with the conventional measurement method, the difference in tree height was 0.02-0.09m and DBH was 0.01-0.04m. If information on the location of vegetation and crowns of each object is constructed through additional research in the future, the efficiency of the work related to forest management information construction can be greatly increased.

The purpose of the study is to analyze how to document survey and repair data on wooden architecture culture assets. Documentation was analyzed in comparison to digital developments from the past to the present. Although the accuracy of survey equipment has been improved by digital development, survey drawing has not changed. For example, a 3D Scanner, survey equipment, was introduced but is being used for conversion into 2D data. Data provided by the drawing included in the survey and repair reports were not accumulated. As it stands, it is inaccessible and disorganized. Data generated from the survey, repair, and maintenance has to be consistent. A BIM system was proposed to integrate information on wooden architecture cultural assets.

최근 3D 스캐너의 필요성이 강하게 대두되고 있으며 이에 따라 다양한 기관에서 3D 스캐너에 대한 연구를 진행하 고 있다. 광학 스캐너는 일정한 구조광 패턴을 물체에 투사한 후 카메라로 촬영된 패턴을 분석하여 대상 물체의 3차 원 형태를 재구성한다. 그러나 핸드헬드 스캐너에서 프로젝터를 사용하면, 기구를 빠르게 움직이면서 생긴 영상의 흐려짐(blur)으로 인해 계산된 포인트 클라우드의 3차원 좌표에 오류가 발생한다. 이 때문에 촬영한 영상에 모션 블러의 발생여부를 검사해야한다. 모션 블러가 발생한 프레임이 감지되면 그 데이터는 최종 3차원 모델 생성에 사용 해서는 안된다. 이 논문에서는 대각선 방향의 격자형 구조광 패턴을 프로젝션 할 때 모션블러의 발생여부를 확인하 기 위하여, 서로 수직인 대각선의 교차점을 각 대각선 방향의 Gabor 필터를 이용하여 찾는 기법에 대해 설명한다. 또한 스캔된 영상들이 실시간으로 입력되는 경우에도 교차점을 검출할 수 있도록 GPU로 병렬 처리하는 방법을 설명한다.

Recently, the necessity of the 3D scanner is rising, and various institutions are conducting research on the 3D scanner. An optical scanner projects a structured light pattern onto an object and analyzes the pattern photographed by a camera to reconstruct a three-dimensional shape of the object. However, using a projector in a handheld scanner results in errors in the calculated three-dimensional coordinates of the point cloud due to the blurring of the image resulting from the fast movement of the instrument. For this reason, it is necessary to check whether motion blur has occurred in the captured image. If a frame with motion blur is detected, the data should not be used to generate the final three-dimensional model. In this paper, we describe a technique to find the intersections of diagonal lines perpendicular to each other by using Gabor filters in order to check whether motion blur occurs when projecting a grid-shaped structured light pattern in a diagonal direction. In addition, a description will be given of a method of parallel processing by the GPU to detect an intersection even when scanned images are input in real time.

Background The production of personalized short leg brace (SLB) and insole orthoses using three- dimensional (3D) printing offers efficiency and addresses limitations of traditional methods involving plaster molds. To fabricate 3D printing orthoses, a 3D scanner capable of acquiring personalized models of individual lower limb segments is necessary. Thus, investigating the reliability and validity of clinical application of a 3D scanner is a foundational step in customized orthoses production. Purpose To verify the reliability and validity of lower leg and foot measurement data related to the SLB fitting process obtained through 3D lower limb scanning equipment. Study design A cross-sectional and repeated-measures study design Methods This study involved 40 adult participants. Inter-rater reliability of a novel 3D scanner was assessed through measurements performed by two different raters within a 3-day interval. Criterion validity of the 3D scanner was verified through comparison with physical measurements. Intraclass correlation coefficient (ICC) were used to investigate inter-rater reliability and criterion validity for measurement variables of the 3D scanner equipment. Results The inter-rater reliability for the 3D scanner showed excellent correlation with ICC 0.90 or higher for most measurement variables. For the validity of the 3D scanner, ICC values of rater A ranged from 0.84 to 0.96 (p<0.01) and those of rater B ranged from 0.91 to 0.99 (p<0.01). The average ICC value was 0.86 for navicular height, medial malleolus height, and lateral malleolus height variables. However, most ICC values showed very good and reliable correlation. Conclusions The inter-measurement reliability of each measurement variable through test-retest of the 3D scanner equipment showed a high level of good correlation. There was a high level of correlation for most measurement variables between caliper measurements directly performed by the rater and 3D scanner measurements. Therefore, production and clinical application of 3D printing-based personalized SLB and insole orthoses could correct, manage, and treat various musculoskeletal diseases of the lower extremities through clinical use of 3D scanner equipment.

In this study, an investigation was made on bristles for the prosthetic and periodontally involved patients based on the previous studies. The purpose of this study was to investigate the ideal location and dimensions of bristles for the patients who were installed with fixed prostheses and severely involved periodontitis. 3D scanner was used to develop 3D visual models of bristles and teeth. These models were developed to be used for designing the ideal bristles for the prosthetic and periodontally involved patients. For the ideal design of bristle, interproximal area of dental arch and bristle must get into maximum and standard teeth may have to be chosen from many gypsum molds. During the design process the factors should be considered that influence the removal of plaque by bristle.

구두를 제작하는 기본 틀인 라스트는 3차원 형상과 관련된 정보와 기술이 총체적으로 집약된 결과물이다. 해외에서는 이미 3D 프틴팅 기술을 이용한 구두 제작이 상용화 단계에 도달하였으나, 국내에서는 아직 도입 초기 단계이다. 본 연구에서는 국내 제화산업의 경쟁력 확대를 위해, 3D 스캐닝, 3D 모델링, 3D 프린팅의 첨단 기술로 구성된 3D 제작 프로세스를 라스트 제작에 도입하였다. 이를 위해, 2010년도 SizeKorea에서 3D 스캔한 30대 남성 200명의 3D 발 형상을 사용하여, 요인분석, 군집분석을 실시하고, 3개의 발 유형을 분류한 후, 각 유형별 대표모델을 선정하였다. 대표모델들의 3D 스캐닝 형상에서 XY, YZ, XZ평면의 단면도들을 추출하고, 라스트 모델링의 스케치 단면으로 사용하였다. Solidworks CAD를 사용하여 라스트를 3D 모델링하였으며, 보급형 3D 프린터인 MakerBot Replicator2로 3D 프린팅 하였다. 본 연구 결과는 국내 제화산업에서 3D 프린팅 기술의 상용 가능성을 보여주었다. 3D 스캐닝, 3D 모델링, 3D 프린팅의 3단계 생산설계 방식은 향후 의류패션산업 전 분야에서 폭넓게 사용될 것으로 기대된다.

The shoe last which is the framework for the shoemaking is intensively combined with the 3D data and technologies. International shoe companies have already commercialized 3D printing technology in producing the shoe, but domestic shoe companies are still in their early stages. This study used the 3D scanning, 3D modeling and 3D printing of the high-technology to make the shoe last. This 3D producing processes should be helpful in building competitiveness in domestic shoe industry. The 3D foot scanning data of men in 30s(n=200) were collected in SizeKorea(2010). The basic statistics, factor and cluster analysis were performed. They were categorized in 3 groups by 3D foot measurement data, and the standard models were selected in each group. The cross sections in XY, YZ and XZ planes sliced from 3D scan data of the standard model were used in the sketches of the 3D shoe last modeling. The 3D shoe last was modeled by Solidworks CAD and printed by MakerBot Replicator2; a desktop 3D printer. This research showed the potential for utilization of 3D printing technology in the domestic shoe industry. The 3D producing process; 3D scanning, 3D modeling and 3D printing is expected to utilized widely in the fashion industry within the nearest future.

3차원 스캐너는 실제 대상을 손쉽게 디지털화한다는 점에서 제조업, 건설업 등 여러 분야에 적용되고 있다. 드론으로 측량한 뒤 정밀한 부분을 요하는 곳에서 3차원 스캐너로 스캐닝하고 토공이나 성토 등의 지형이 변형되었을 경우 3차원 스캐너로 측량하여 기존데이터와 새로운 데 이터를 결합하는 방법과 과정에 대해 연구하고자 한다. 본 연구에서는 최종목표에 도달하기 위 한 초기연구로 MMS를 이용하여 차량이동시 LiDAR 계측기 한개의 데이터와 GPS데이터 연동 실험을 하였고 LiDAR 계측기와 GPS 데이터 연동실험 결과 디지털 맵 구현을 위한 포인트클라 우드를 얻을 수 있었다.

성능 위주 화재안전성능설계(PBD)에 있어서 설계화원(Design fire source)은 중요한 파라미터이다. 설계 화원은 가연물 조사의 축적을 통하여 설정할 수 있으며, 본 연구진은 편리한 가연물 조사방법의 확립을 목 적으로 3차원 스캐너를 이용한 가연물 조사법(3Ds법)에 대한 연구를 수행해왔다. 3Ds를 이용하여 4개소(17 개 실)의 건축물을 대상으로 가연물 조사를 하였다. 조사 대상물에는 통로 공간(가연물이 비교적 적은 공 간) 및 용도 공간(가연물의 수량이 많은 공간)이 포함되도록 선택하였다. 한편, 3Ds법의 신뢰성을 확인하기 위하여, 종례법(가연물의 이름, 치수 및 중량 등을 직접 조사)에 의한 가연물 조사를 병행하였다. 본 논문 에서는 조사 대상물, 3Ds법의 개요와 조사된 화재밀도 그리고 앞으로 과제에 대하여 설명하였다.

In recent years, studies on various 3D scanner applications, including those on quality control and reverse engineering, have been conducted in the shipbuilding industry. Appropriate scanner selection, scanning environment setting by targets, and data postprocessing are essential for effective 3D scanning projects for small crafts. In this study, a non-contact handheld-type 3D scanner was used for molds and hull products for the 10–30-ft class of small crafts. Small crafts have fewer geometric features and several glare surfaces; thus, anti-glare and texture feature addition preprocessing is critical. The 3D scanning results are used for geometry quality control of single panels and curved surfaces in craft hulls. Consequently, international rule-based weight estimation calculation sheets have been developed and applied for product weight quality control.

본 논문에서는 무인 지상 차량(UGV)이 야지 조건에서 주행할 수 있는 영역을 탐지하는 방법을 제안한다. UGV는 일반 차량이 주행하는 포장도로가 아닌 산이나 들판과 같은 야지에서 주행이 가능한 지역을 판단하는 것이 중요하 다. 이를 위해 우선 3D 레이저 스캐너를 사용하여 주행 환경을 거리 이미지 형태로 변환한다. 이를 활용하여 한 프 레임에 수백만 개가 계측되는 레이저 스캐너의 데이터를 2차원 이미지로 빠르게 처리한다. 거리 이미지를 사용하여 주행 차량의 진행 방향뿐만 아니라 좌우 경사의 기울기를 고려하여 주행이 가능한 영역을 탐지한다. 또한 거리 이미 지에서 인접한 픽셀 사이의 각도 차이를 이용하여 각도 이미지를 만들고 이에 스무딩 방법을 적용한다. 이를 통해 차량이 존재하는 위치에서부터 탐색을 시작하여 현재 위치와 유사한 노면의 기울기를 가진 영역을 검사한다. 이를 통해 최종적으로 야지의 조건에서 UGV가 주행이 가능한 영역을 판단하는 알고리즘을 제안한다. 그리고 제안한 방 법의 우수성을 검증하기 위해 실제로 야지를 주행하여 실제 데이터를 수집하고 이를 기반으로 제안한 방법과 기존 방법과의 비교를 진행한다.

In this paper, I propose a traversable region detection method by which an unmanned ground vehicle(UGV) can drive in an off-road condition. It is necessary for UGVs to determine traversable regions when travelling in off-road conditions such as mountains or fields, as opposed to driving on a paved road. To this end, a 3D laser scanner is used to measure the surrounding environment accurately. To process a number of point clouds from a 3D laser scanner efficiently, I propose a range image based traversable region detection approach. In addition, by proposing a traversable detection algorithm that considers not only the traveling direction of the vehicle but also the slope of the left and right slopes, it limits robust performance in various rough terrain conditions. In order to verify the superiority of this method, actual data is collected by driving on rough terrain, and based on this, the proposed method and the existing method are compared.

Purpose: The purpose of this study was to evaluate the validity of digital models fabricated by difference optical source of non-contact 3D dental scanner. Methods: A master model with the prepared upper full arch tooth was used. Stone model(N=10) were produced from master model, and on the other hands, digital models were made with the 3D dental scanner(Blue, white, red optical source). The linear distance between the reference points were measured and analyzed on the Delcam CopycadⓇ graphic software. The results were statistically analyzed using the one-way ANOVA and Tukey’s HSD test(α=0.05). Results: There were considerable differences in mean values between optical source within each color(blue, white, red), and this difference was not statistically significant(p>0.05). Conclusion : Three different color of dental scanner optical source showed clinically acceptable accuracies of full arch digital model produced by them. Besides, these results will have to be confirmed in further clinical studies.

Purpose: The purpose of this study was establishing process of manufacturing dental prosthesis by using eZIS system(DDS Inc.,Korea). Methods: To evaluate accuracy verification, the test was practiced two ways. First, Comparison of 3D printing models and stone models was practiced by using 3D superimposing software. #36 prepared master model was scanned by eZIS system and three ‘Veltz3D’ 3D printing models and three ‘Bio3D’ 3D printing models were manufactured. three stone models were manufactured by conventional impression technique. Second, Fitness test was practiced. the 3D printing models and the stone models was compared by manufacturing same resin crown. #36 prepared master model was scanned 9 times and manufactured (milled) 9 resin crowns by eZIS system. These crowns were cemented three ‘Veltz3D’ 3D printing models, three ‘Bio3D’ 3D printing models and three stone models. These crowns were sliced mesiodistal axis and gaps were measured by digital microscope. Results: The average accuracy of Bio3D models were 65.75%. Veltz3D(Hebsiba) models were 60.11% Stone models were 41.00%. Conclusion : This study results showed 3D printing model is similar with stone model. So it was under clinical allow, didn’t affect final dental prothesis. There were no significant differences in the appearance of the three types of milling crowns.

기존의 도자기의 복원방법은 수작업에 의존한 방식으로 처리자의 개인능력에 따라 처리기간과 복원 결과물이 차이를 나타낸다. 또한 복원재료로 많이 사용되는 합성수지는 물성과 접착력이 우수하고 경화 후 수축이 적으며 각종 충전제를 첨가할 수 있는 장점은 있지만, 작업성이 떨어져 보존처리 과정에서 유물 표면이 오염될 수 있고 빛과 온도 등 주변 환경에 의해황변현상이 발생하는 문제가 있다. 이에 본 연구에서는 기존의 처리방식과 복원재료의 한계를극복하기 위해 3D 프린팅 기술을 활용한 새로운 방법으로 익산 미륵사지 분청사기 인화 국화문 대접과 부여 송국리 무문토기완을 복원하였으며 도자기의 표면질감과 유사한 프린터재료를 선정 후 복원재료로서 적합성을 연구하였다. 그 결과, 3D 프린팅을 활용한 유물복원은 수작업 처리방식에 비해 처리기간을 단축할 수 있었으며 모델링 데이터의 수정을 통해 복원 완성도를 높일 수 있었다. 또한 복원재료로 사용한 아크릴 화합물(VeroWhite Plus RGD 835)과 석고(Z151 power, 3D Systems 社, U.S.A)는 도자기의 표면질감과 매우 유사하여 이질감을 나타내지 않았고 작업성이 편리하여 처리과정에서 발생할 수 있는 2차 손상을 최소화할 수 있었다. 다만, 채색과정에서 석고는 표면재질이 거칠어 물감이 쉽게 흡수된 반면, 아크릴 화합물은 재질이 매끄러운 특성으로 인해 표면 마찰력이 떨어져 물감이 쉽게 정착되지 못함을 확인하였으며 다양한 채색방법을 적용한 결과 분사방법을 이용해 반복채색 하는 것이 가장 효과적이라는 것을 알게 되었다.

The restoration method of pottery is based on Conservator-restorers and depending on the individual ability the processing period and the restoration result are different. In addition, synthetic resin, which is widely used as a restoration material, has excellent physical properties and adhesion, has fewer contractions after hardening and has the advantage of adding various filling agents, but there is a problem that the surface of the artifacts may be polluted during the conservation process due to lack of workability and yellowing phenomenon occurs due to the surrounding environment such as ultraviolet rays and humidity. In this study, in order to overcome the limitations of existing treatment methods and restoration materials, a Punchung dish from Iksan Mireuksa-ji and Unglazed earthenware from Buyeo Songguk-ri were in restored, After selecting printer materials similar to the surface texture of pottery, studied the suitability as restoration materials. As a result, restoration of artifacts using 3D printing was able to shorten the processing period, compared to the manual processing method, and the restoration completeness was improved by modifying the modeling data. Also, acrylic compounds (Vero White Plus RGD 835) and gypsum (Z151 power, 3D systems, U.S.A.) used as restoration materials were also being very similar to the surface of pottery Convenient workability was easier to minimize the secondary damage that could occur during the processing process. But during the coloring process, the gypsum is rough in the surface material and the paint was easily absorbed into the material, while the acrylic compound was found to have a smooth material and the surface frictional force was reduced and the paint was not easily attached to the material and the result of applying various coloring methods used, a spray repeat coloring found it most effective.

Currently, it is usually a 3D scanner processing method as a laser method. However, the laser method has a disadvantage of slow scanning speed and poor precision. Although optical scanners are used as a method to compensate for these shortcomings, optical scanners are closely related to the distance and precision of the object, and have the disadvantage of being expensive. In this paper, 3D scanner using variable focus lens-based structured light module with improved measurement precision was designed to be high performance, low price, and usable in industrial fields. To this end, designed a telecentric optical system based on a variable focus lens and connected to the telecentric mechanism of the step motor and lens to adjust the focus of the variable lens. Designed a connection structure with optimized scalability of hardware circuits that configures a stepper motor to form a system with a built-in processor. In addition, by applying an algorithm that can simultaneously acquire high-resolution texture image and depth information and apply image synthesis technology and GPU-based high-speed structured light processing technology, it is also stable for changes to external light. We will designed and implemented for further improving high measurement precision.

3D scanners are needed in various fields, and their usage range is greatly expanded. In particular, it is being used to reduce costs at various stages during product development and production. Now, the importance of quality inspection in the manufacturing industry is increasing. Structured optical system applied in this study is suitable for measuring high precision of mold, press work, precision products, etc. and economical and effective 3D scanning system for measuring inspection in manufacturing industry can be implemented. We developed Structured light 3D scanner which can measure high precision by using Digital Light Processing (DLP) projector and camera. In this paper, 3D image scanner based on structured optical system can realize 3D scanning system economically and effectively when measuring inspection in the manufacturing industry.

This paper describes a low-cost miniaturized 3D reconstruction approach using structured light. By projecting known patterns onto a surface, shape and structure of the surface can be measured and characteristic parameters of deformation can be determined. Existing approaches use large geometries and complex optical components. Here we present our system with the size of a cigarette pack and a working distance of only 6 cm. The theoretical depth resolution of the system is determined by the resolution of the camera and the projector as well as the system geometry and was found to be about 100 μm.

19세기말 카메라의 발명은 미술에서 자연의 모방으로부터 벗어날 수 있게 된 것을 넘어 현대 미술이 추구하는 시간성과 재현성을 구현 시킬 수 있는 뉴 미디어 아트로 각광 받고 있다. 3D 스캐너는 카메라의 광학적 원리에 컴퓨터 기술이 더해져 3D 가상공간을 통해 영상 합성기술이 실생활에 적용 되고 있다. 이렇듯 3D 스캐너와 컴퓨터의 결합은 생산 공정 관리 및 디자인 제품개발에 이르기 까지 여러 분야에 적극 활용 되어 지고 있다. 그중에서 3D 스캐너를 활용한 디자인 장비는 제품의 프로세스를 신속, 정확, 다양하게 변화시키고 있다. 멀티 카메라 방식과 컴퓨터 3D 프로그램을 결합시켜 제품이나 부품을 원형그대로 재현시킬 수 있으며 3D프린터, 3D조각기, 3차원조각기, 다관절 로봇, 등 다양한 종류의 실행 기계와 함께 자동차, 조선, 모바일, 금형, 섬유업체 등 전 산업에 활용되어지고 있다. 한편 도자분야의 경우 몇몇 대학교만이 초보적 단계로 활용되어 지고 있는 실정이다. 따라서 본 연구는 3D 스캐너 활용을 통해 대상물을 측정하고 그 데이터를 도자디자인에 적용시킴으로서 도자 산업 뿐 아니라 개인 도자작업에 응용되어 질 수 있는 가능성을 찾고자 하였다. 그래서 본 논문에서 3D 스캐너를 활용해 복원 또는 디자인 방법에서 D/B구축을 통한 효율적인 생산 시스템의 전환을 통해 도자분야에 적용될 수 있는 방법을 제시 하고자 한다.