• Title/Summary/Keyword: 수치제어가공

Search Result 6, Processing Time 0.169 seconds

Offset of STL Model Generated from Solid Model (솔리드 STL 모델의 옵셋 방법)

  • Kim, Su-Jin;Yang, Min-Yang
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.22 no.9
    • /
    • pp.202-211
    • /
    • 2005
  • This paper introduces and illustrates the results of a new method fer offsetting triangular mesh by moving all vertices along the multiple normal vectors of a vertex. The multiple normal vectors of a vertex are set the same as the normal vectors of the faces surrounding the vertex, while the two vectors with the smallest difference are joined repeatedly until the difference is smaller than allowance. Offsetting with the multiple normal vectors of a vertex does not create a gap or overlap at the smooth edges, thereby making the mesh size uniform and the computation time short. In addition, this offsetting method is accurate at the sharp edges because the vertices are moved to the normal directions of faces and joined by the blend surface. The method is also useful for rapid prototyping and tool path generation if the triangular mesh is tessellated part of the solid models with curved surfaces and sharp edges. The suggested method and previous methods are implemented on a PC using C++ and illustrated using an OpenGL library.

NURBS Post-Processing of Linear Tool Path (미소직선 공구경로의 NURBS 변환)

  • Kim, Su-Jin;Choi, In-Hugh;Yang, Min-Yang
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.7
    • /
    • pp.1227-1233
    • /
    • 2003
  • NURBS (Non Uniform Rational B-Spline) is widely used in CAD system and NC data for high speed machining. Conventional CAM system changes NURBS surface to tessellated meshes or Z-map model, and produces linear tool path. The linear tool path is not good fur precise machining and high speed machining. In this paper, an algorithm to change linear tool path to NURBS one was studied and the machining result of NURBS tool path was compared with that of linear tool path. The N-post including both a post-processing and a virtual machining software was developed. The N-Post transforms linear tool path to NURBS tool path and quickly shades a machined product on OpenGL view, while comparing a machined surface with a original CAD one. A virtulal machined model of original tool path and post-processed tool path was compared to original CAD model. The machining error and machining time of post-processed NURBS tool path were investigated.

NURBS Post-processing of Linear Tool Path (미소직선 공구경로의 NURBS 변환)

  • Kim, Su-Jin;Choi, In-Hugh;Yang, Min-Yang
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.1111-1117
    • /
    • 2003
  • NURBS (Non Uniform Rational B-Spline) is widely used in CAD system and NC data for high speed machining. Conventional CAM system changes NURBS surface to tessellated meshes or Z-map model, and produces linear tool path. The linear tool path is not good for precise machining and high speed machining. In this paper, an algorithm to change linear tool path to NURBS one was studied, and the machining result of NURBS tool path was compared with that of linear tool path. The N-post, post-processing and virtual machining software was developed. The N-Post post-processes linear tool path to NURBS tool path and quickly shades machined product on OpenGL view and compares a machined product with original CAD surface. A virtual machined model of original tool path and post-processed tool path was compared to original CAD model. The machining error of post-processed NURBS tool path was reduced to 43%. The original tool path and NURBS tool path was used to machine general model using same machine tool and machining condition. The machining time of post-processed NURBS tool path was reduced up to 38%.

  • PDF

Offset of STL Model Generated from Multiple Surfaces (열린 STL 모델의 옵셋 방법)

  • Kim Su-Jin;Yang Min-Yang
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.23 no.7
    • /
    • pp.187-193
    • /
    • 2006
  • This paper introduces and illustrates the results of a new method for offsetting the triangular mesh generated from multiple surfaces. The meshes generated from each surface are separated each other and normal directions are different. The face normal vectors are flipped to upward and the lower faces covered by upper faces are deleted. The virtual normal vectors are introduced and used to of feet boundary. It was shown that new method is better than previous methods in offsetting the triangular meshes generated from multiple surfaces. The introduced offset method was applied for 3-axis tool path generation system and tested by NC machining.

Development of Post-Processor and Cutting Motion Simulator for 5-axis CNC Laser Cutting Machine (5축 레이저 절단기용 포스트프로세서 및 절단 모션 시뮬레이터 개발)

  • Kang, Jae-Gwan
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.8 no.4
    • /
    • pp.7-13
    • /
    • 2009
  • Five-axis laser cutting has great advantages when it is applied to 3-dimensional machining requiring high cutting quality. For developing 5-axis CNC laser cutting systems, however, many problems such as rotating a laser head or a working table, 5-axis servo-control mechanism, tool path generation and post processing, and collision avoidance between a laser head and a work-piece should be solved. In this paper, we deal with developing a dedicated CAM system based on UG-NX3 for 5-axis laser cutting machine. Two essential modules such as post-processor and cutting motion simulation was developed. The developed system was applied to cutting curve defined on 3-D workpiece in order to show the validity of the proposed methods.

  • PDF

A Study on the 3-D CNC Cutting Planning and Simulation by Z-Map Model (Z-Map 모델을 이용한 3차원 CNC 가공계획 및 절삭시뮬레이션에 관한 연구)

  • 송수용;김석일
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.683-688
    • /
    • 1994
  • Recently, the Z-Map model has been used widely to represent the three dimensional geometric shape and to achieve the cross-section and point evaluation of the shape. In this paper, the CNC cutting planning and simulation modules for product with three dimensional geometric shape are realized based on the Z-Map model. The realized system has the various capabilities related to the automatic generation of tool path for the rough and finish cutting processes, the automatic elimination of overcut, the automatic generation of CNC program for a machining center and the cutting simulation. Especially, the overcut-free tool path is obtained by using the CL Z-Map models which are composed of the offset surfaces of the geometric shape of product.

  • PDF