Methodology proposal for geometric modeling in the CAD/CAM system from the medical images

2009 ◽  
Author(s):  
O. Canciglieri-Jnr ◽  
J. A. Harding ◽  
J. Harrison
Keyword(s):  
Geometric Modeling ◽  
Medical Images ◽  
Cad Cam

Research on Machining Simulation of Ultra High-Speed Grinding Machine Tool Based on Web

2010 ◽  
Vol 126-128 ◽  
pp. 77-81
Author(s):  
Wan Shan Wang ◽  
Peng Guan ◽  
Tian Biao Yu
Keyword(s):  
Machine Tool ◽  
Geometric Modeling ◽  
High Speed ◽  
Cnc Machining ◽  
Machining Process ◽  
Machining Simulation ◽  
Ultra High Speed ◽  
Cad Cam ◽  
High Speed Grinding ◽  
Grinding Machine

The future development of the manufacturing is using VR technology to make the machining simulation before the actual machining process made. The machining simulation of Ultra High-speed Grinding Machine Tool is researched in this paper. Firstly, using UG/NX software and VRML, the geometric modeling of machine tool is modeled. Secondly, through using Java and Javascript language, the operation and display of machining process of ultra high-speed grinding are realized. The main technologies include NC codes compiling, collision detection and material removal. Thirdly, the example of machining simulation using virtual ultra high-speed grinding machine tool can be obtained in the paper. Compared to other CNC machining simulation methods, the method in the paper has reality display, rich features, a good man-machine interaction, etc., and it does not rely on expensive CAD/CAM software. The system files generated by the machining simulation have the small size and can be transferred on the network easily.

Optimal Boundary Triangulations of an Interpolating Ruled Surface

2005 ◽  
Vol 5 (4) ◽  
pp. 291-301 ◽  
Author(s):  
Charlie C. L. Wang ◽  
Kai Tang
Keyword(s):  
Shortest Path ◽  
Geometric Modeling ◽  
Search Space ◽  
Shortest Path Problem ◽  
Ruled Surface ◽  
Search Problem ◽  
Combinatorial Search ◽  
Single Source ◽  
Cad Cam ◽  
Optimal Triangulation

We investigate how to define a triangulated ruled surface interpolating two polygonal directrices that will meet a variety of optimization objectives which originate from many CAD/CAM and geometric modeling applications. This optimal triangulation problem is formulated as a combinatorial search problem whose search space however has the size tightly factorial to the numbers of points on the two directrices. To tackle this bound, we introduce a novel computational tool called multilayer directed graph and establish an equivalence between the optimal triangulation and the single-source shortest path problem on the graph. Well known graph search algorithms such as the Dijkstra’s are then employed to solve the single-source shortest path problem, which effectively solves the optimal triangulation problem in O(mn) time, where n and m are the numbers of vertices on the two directrices respectively. Numerous experimental examples are provided to demonstrate the usefulness of the proposed optimal triangulation problem in a variety of engineering applications.

An Approach for Generating Variational Geometry of a Pattern of Holes With Composite Positional Tolerances

2002 ◽  
Author(s):  
Y. S. Liu ◽  
S. M. Gao
Keyword(s):  
Mathematical Models ◽  
Geometric Modeling ◽  
Mechanical Design ◽  
Cad Systems ◽  
Computer Aided ◽  
Cad Cam ◽  
Positional Tolerance

In most present CAD systems, the accurate geometry representation of a part is given but the tolerance is just a text attribute without semantics. It hampers the integration of CAD/CAM. In last two decades, much research has been conducted on computer aided tolerancing. And many approaches to generation of variational geometry for various kinds of features have been given. However how to generate the variational geometry of a pattern of holes (POH) is not well studied yet although a POH is one of the most widely-used features in mechanical design. Based on DOF, an approach is proposed for generating variational geometry of a POH with composite positional tolerance in this paper. First, the limitation conditions for variations of a POH are given. Second, the mathematical models of translational and rotational variations are systematically derived. Then the algorithm for generating variational geometry of a POH is given. At last the proposed approach has been implemented with Visual C++ based on the geometric modeling kernel ACIS5.0.

Kinematics-Based Geometric Design of Sculptured Surfaces

1996 ◽  
Author(s):  
Q. J. Ge ◽  
Donglai Kang
Keyword(s):  
Geometric Modeling ◽  
Tool Path ◽  
Geometric Design ◽  
Geometric Shape ◽  
Shape Design ◽  
Path Generation ◽  
Sculptured Surfaces ◽  
Computer Aided ◽  
Cad Cam ◽  
Cad Models

Abstract Current practice in CAD/CAM separates the process of geometric shape design from that of CMC (Computer Numerically Controlled) tool path generation. Although successful for 3-axis machining, this strategy is not as effective for 5-axis machining of sculptured surfaces due to the difficulty in generating accurate and gouge-free 5-axis tool paths from the CAD models. This paper presents a framework for a new, kinematics-based methodology for geometric modeling that integrates sculptured-surface design with too-path generation for 5-axis CMC machining. In particular, sculptured surfaces are represented directly in terms of rational Bézier and B-spline motions of the cutting tool. The proposed framework brings together the fields of Kinematics and Computer Aided Geometric Design as well as the recent results in Computer Aided Motion Synthesis and Swept Volume Modeling and provides a basis for concurrent geometric shape design and manufacture.

Analysis on Quality Evaluation Criteria for Spline Curves

2013 ◽  
Vol 365-366 ◽  
pp. 99-103
Author(s):  
Shi Jun Ji ◽  
Ji Zhao ◽  
Lei Zhang ◽  
Hui Juan Yu ◽  
Xiao Long Liu ◽  
...  
Keyword(s):  
Curve Fitting ◽  
Geometric Modeling ◽  
Quality Evaluation ◽  
Evaluation Criteria ◽  
Affecting Factors ◽  
Spline Curve ◽  
Spline Curves ◽  
Fitting Method ◽  
Cad Cam ◽  
Curve Fitting Method

With the development of CAD/CAM, reverse engineering, geometric modeling, animation and computer graphics. In the past fifty years, many kinds of spline curve fitting methods have been produced. But, to authors knowledge, quality evaluation criterion about different spline curves are still not established and there is a lack of a comparing standard for analyzing different spline curves. Two spline curve fitting method comparing theorem is given and several various spline curves affecting factors are analyzed in this paper. Some comparable results are obtained by using the proposed quality evaluating theorem to different spline curves.

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