• 제목/요약/키워드: STL

검색결과 302건 처리시간 0.021초

STL의 오류수정 및 형상수정 시스템의 개발 (System Developement for STL Error Correction and Shape Modification)

  • 채희창
    • 한국정밀공학회지
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    • 제16권3호통권96호
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    • pp.53-61
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    • 1999
  • STL has several errors such as orientation error, hole error, and acute triangle error on being translated from CAD software. These errors should be corrected before using in Rapid Prototyping. So the software is necessary to correct errors. In this study, STL Editor which is a system for STL error correction and shape modification is developed and contains following characteristics. 1.Apply the triangle based data st겨cture. 2.Use the graphic user interface for easy work. 3.Use the Diet method to reduce data size. 4.Use the Delaunay triangulation method to enhance the quality of STL. 5.Modify the STL errors manually.

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STL offset을 이용한 다이레스 CNC 포밍용 등고선 공구경로 생성 (Contouring Tool Path Generation for Dieless CNC Forming using STL Offset)

  • 강재관;최동우
    • 한국정밀공학회지
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    • 제23권2호
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    • pp.191-198
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    • 2006
  • Dieless CNC forming is an innovative technology which can form various materials with complex shape by numerically controlled incremental forming process. In this paper, a method of NC tool path generation based on an STL file for dieless CNC forming is proposed. Tool trajectory adopts the principle of layered manufacturing in rapid prototyping technology, but it is necessary to consider STL offset because of the ball shaped tool with a radius. Vertex offset method which enables to compute offset STL directly is engaged for STL offset. The offseted STL is sliced by cutting planes to generate contouring tool path. Algorithm is implemented on a computer and experimented on a dieless CNC forming machine to show its validity.

버텍스 영역을 이용한 STL에서의 3차원 디지털 워터마킹 (A 3D Watermarking on STL using Vertex domain)

  • 김기석;천인국
    • 한국멀티미디어학회:학술대회논문집
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    • 한국멀티미디어학회 2002년도 춘계학술발표논문집(하)
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    • pp.901-906
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    • 2002
  • 본 논문은 신속조형(RP: rapid prototyping) 시스템에서 사용되며 3D 기하학적 형상 모델을 가지고 있는 STL(standard transform language)에 워터마크를 삽입하는 방법에 관한 연구이다. 제안된 알고리즘은 3D 형상 데이터의 왜곡이 전혀 없이 패싯(facet, mesh)의 버텍스(vertex) 영역에 워터마크를 삽입한다. 기존의 알고리즘으로 STL에 워터마크를 삽입할 경우, 패싯의 저장순서를 변경하는 단순한 공격으로도 워터마크가 제거된다. 제안된 알고리즘은 패싯의 저장 순서 변경과 같은 공격에 대한 강인성을 가질 뿐만 아니라, 비가시성(invisibility)도 충족한다. 제안된 알고리즘으로 STL 3D 형상에 워터마크를 삽입하고 추출하는, 실험 결과들은 3D 원형상을 전혀 왜곡하지 않고 워터마크의 삽입과 추출이 가능함을 보여준다.

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삼각형기반 형상모델러를 이용한 STL의 검증 (Verification of STL Using the Triangle Based Geometric Modeling)

  • 채희창;황동기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.578-582
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    • 1996
  • Verification of STL is essential in RP. In the study, triangle based non-manifold geometric modeling that can check intersection between triangles was used to vilify STL. The method proposed in this study can be applied at the most general case and very useful, but has a penalty on computing thime of O(n$^2$)

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급속조형 시스템을 위한 STL 포맷의 오류 검증에 관한 연구 (A Study on Error Verification of STL Format for Rapid Prototyping System)

  • Park, H.T.;Lee, S.H.
    • 한국정밀공학회지
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    • 제13권10호
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    • pp.46-55
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    • 1996
  • As industrial standard data, the STL format which approximates three dimensional CAD model to triangular facets, is used for RP(Rapid Prototyping) system in recent days. Because most RP system take the only form of two dimensional line segments as an input stream inspite of its imperfectness while converting into STL format, a CAD model is converted into a standard industrial format which is composed of many triangular facets. The error verifying process is composed of four main steps, and these are 1) Remove facets with two or more vertices equal to each other. 2) Fix overlapping error such as more than three facets adjacent to anedge. 3) Fill holes in the mesh by using Delaunay triangulation method. 4) Correct the wrong direction and normal vectors. This paper is concerned with serching the mentioned errors in advance and modifying them.

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급속조형시스템을 위한 STL 포멧의 오류 검증에 관한 연구 (A Study on Error Verification of STL format for Rapid Prototyping System)

  • 최홍태;이석희
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.597-601
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    • 1996
  • Nowadays, the STL format, industrial standard data, which approximates three dimensional CAD model to triangular facets, is used for RP(Rapid Prototyping) system. Because most RP machine is accpted to only two dimensional line segments, but some STL translators are sometimes poorly implemented. The error verifying process is as follows. 1) Remove facets with two or more vertices equal to each other. 2) Fix overlapping error such as more than three facets adjacent to an edge. 3) Fill holes in the mesh by using Delaunay triangulation method. 4) Repair wrong direction and value of normal vectors. This paper is concerned with searching the mentioned errors in advance and modifying them.

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STL에 위상정보를 부여하기 위한 삼각형 기반 형상모델링 (Creation of Topological Information from STL Using Triangle Based Geometric Modeling)

  • 채희창
    • 한국정밀공학회지
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    • 제14권2호
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    • pp.136-144
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    • 1997
  • Usually triangular patches are used to transfer geometric shape in Rapid Prototyping CAM system. STL, a list of triangles, is de facto standard in RP industry. Because STL does not have topological infoma- tion, it can cause errornous results. So STL should be verified before using. After adding support structures to anchor the part to the platform and to prevent sagging or distortion, slicing and layer by layer manufactur- ing process are done. But triangular patch is surface model and cannot provide sufficient information on geometry in the above processes. So, geometric modeling is necessary in verifying STL, adding support structures and slicing. It is natural that triangle based modeling is the best when tringular patches are used as input. Considering support structures, solid and faces coexist in RP process. Therefore non-manifold modeler is required. In this study, triangle based non-manifold geometric modeling is proposed for RP sys- tem consistent with STL input.

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쾌속조형 시스템을 위한 3차원 기하학적 형상인 STL의 디지털 워터마킹 (A Digital Watermarking of 3D Geometric Model STL for Rapid Prototyping System)

  • 김기석;천인국
    • 한국멀티미디어학회논문지
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    • 제5권5호
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    • pp.552-561
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    • 2002
  • 본 논문은 쾌속조형(rapid prototyping) 시스템에서 사용되며 3D 기하학적 형상을 가지는 STL 파일에 워터마크를 삽입하고 추출하는 방법에 관한 연구이다. 제안된 알고리즘은 3D 형상의 왜곡이 없도록 하기위해, 패싯의 법선 영역과 꼭지점 영역에 워터마크를 삽입한다. 워터마크 비트들은 법선의 위치와 꼭지점의 순서 정보를 이용하여 삽입된다 제안된 알고리즘은 패싯의 저장 순서에 대한 종속성이 없으며, 워터마크의 비가시성 (invisibility)을 충족한다. 제안된 알고리즘으로 3D 기하학적 형상에 워터마크를 삽입하고 추출하는 실험 결과들은 STL로 표현된 3D원형상에 영향을 주지 않고 워터마크의 삽입과 추출이 가능함을 보여준다.

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삼각형기반 형상모델러를 이용한 STL의 검증 (Verification of STL using the Triangle Based Geometric Modeler)

  • 채희창
    • 한국생산제조학회지
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    • 제6권1호
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    • pp.51-58
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    • 1997
  • The verification of the STL file is essential to build the confident parts using a RP machine, because the STL file obtained from the CAD software has many errors-the orientation of triangle does not coincide with adjacent triangles or some triangles are omitted, overlpped and so forth. Especially, the STL file translated from the surface model has more errors than those translated from the solid model. In this study, all possible errors were classified with the most general from and the causes of errors were analyzed to verify and correct errors. Using the triangle based non-manifold geometric modeling, these errors were corrected. Especially, this study took the notice of the problem about the intersected triangles and non-manifold properties overlooked in the previous studies. But this study has a penalty on computing time of $O(n^2)$.

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STL File 슬라이싱 높이 조정에 따른 주사경로 생성시간 저감에 관한 연구 - 소형 보석류에 적용 (The Study on Reduction of Scanning Path Build Time According to Control of STL file Slicing Height - Application of Small Jewellery)

  • 김태호;김민주;이승수;전언찬
    • 한국정밀공학회지
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    • 제22권12호
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    • pp.205-210
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    • 2005
  • This paper addresses the correlation between the change of file size and the scanning path build time by the slicing height of STL file. Though the study about STL file has been achieved quite actively scanning path build time using STL file is not investigated so much to be satisfied. The file size depends on the number of polygon created by the slicing height specified. And this number of polygons increases in a regular rate. The correlation between the number of polygons and the scanning path build time is examined and verified.