3D CAD: Principles and Applications

ISBN-13: 9783642457319 / Angielski / Miękka / 2012 / 282 str.

Hiroshi Toriya; Hiroaki Chiyokura; H. Yaguchi

Opis

3D CAD is one of the most important technologies of the 90s for the engineering and manufacturing world. 3D CAD systems can provide a competitive edge in the development of new products. This book presents the development of a three-dimensional CAD system and its wide range of applications. It describes the concepts of solid models, and the theory of curves and surfaces and it illustrates these concepts through "reals world" applications.

Spis treści

1 Outline of CAD/CAM/CAE.- 1.1 Introduction.- 1.2 CAD System.- 1.3 CAM System.- 1.4 CAE System.- 1.5 3D CAD Systems.- 2 3D CAD Systems and Solid Models.- 2.1 Introduction.- 2.2 How to Represent Solids.- 2.3 Advantages of a Solid Modeler.- 2.4 Representation of Objects in a Solid Modeler.- 2.4.1 CSG and boundary representations.- 2.4.2 Hybrid systems.- 2.4.3 Other representation methods.- 2.5 Comparison of CSG and Boundary Representations.- 3 Solid Modeler DESIGNBASE.- 3.1 Introduction.- 3.2 Features of DESIGNBASE.- 3.3 Software Structure of DESIGNBASE.- 3.4 Data Structure of Boundary Representations.- 3.4.1 Solid models with boundary representations.- 3.4.2 Data structures of boundary representations.- 3.4.3 Data structure of topological elements in DESIGNBASE.- 3.4.4 Data structure of geometric elements in DESIGNBASE.- 3.5 Primitive Operations.- 3.5.1 Topological elements and Euler formula.- 3.5.2 Euler operations.- 3.5.3 Primitive operations in DESIGNBASE.- 3.6 An Example of Primitive Operations.- 4 Free-Form Curves.- 4.1 Introduction.- 4.2 Parametric Curves.- 4.2.1 Algebraic representation.- 4.2.2 Parametric representation.- 4.3 Bézier Curves.- 4.3.1 How to represent Bézier curves.- 4.3.2 Division and connection of Bézier curves.- 4.3.3 Degree elevation of Bézier curves.- 4.4 Rational Bézier Curves.- 4.4.1 How to represent rational Bézier curves.- 4.4.2 Weights and their effects.- 4.4.3 Creation of conic sections.- 4.5 B-Spline Curves.- 4.5.1 How to represent B-spline curves.- 4.5.2 Knot vectors and curves.- 4.5.3 Connection and division of curves.- 4.6 NURBS.- 4.6.1 How to represent NURBS.- 4.6.2 How to represent conic sections with NURBS.- 4.6.3 Connection of curves.- 4.7 Programs.- 4.7.1 Program to obtain coordinates on a curve.- 4.7.2 Program to obtain a derivative vector on a curve.- 4.7.3 Program to divide a curve.- 5 Free-Form Surfaces.- 5.1 Introduction.- 5.2 Quadric Surfaces.- 5.3 Parametric Patches.- 5.4 Coons Surfaces.- 5.5 Bézier Surfaces.- 5.6 Rational Bézier Surfaces.- 5.7 NURBS.- 5.8 Gregory Patches.- 5.9 Rational Boundary Gregory Patches.- 5.10 Connection of Patches.- 5.10.1 Conditions on connectivity.- 5.10.2 Connection of Gregory patches.- 5.10.3 Connection of rational boundary Gregory patches.- 5.11 Interpolation of Patches.- 5.11.1 Irregular meshes.- 5.11.2 Interpolation of curve meshes.- 5.11.3 Interpolation of triangular surfaces.- 5.11.4 Interpolation of surfaces containing an odd number of sides.- 5.11.5 Interpolation of surfaces containing an even number of sides.- 5.11.6 Interpolation of curve meshes containing T-nodes.- 5.12 Transformation of Patches.- 5.12.1 Transformation between Bézier surface and Coons surface.- 5.12.2 Transformation of rational boundary Gregory patch into rational Bézier surface.- 5.13 Programs.- 5.13.1 Program to obtain coordinates on a surface.- 5.13.2 Program to obtain a partial derivative vector of a surface.- 6 Intersection Calculations.- 6.1 Introduction.- 6.2 Intersection Calculations Between Curves.- 6.2.1 Algebraic calculation method.- 6.2.2 Geometric calculation method.- 6.3 Intersection Calculations Between a Curve and a Surface.- 6.3.1 Algebraic calculation method.- 6.3.2 Geometric calculation method.- 6.4 Intersection Calculations Between Surfaces.- 6.4.1 Intersection calculations between quadratic surfaces.- 6.4.2 Intersection calculations between free-form surfaces.- 6.4.3 Recursive subdivision method.- 6.4.4 Marching method.- 6.5 Intersection Calculation in DESIGNBASE.- 7 Local Operations.- 7.1 Introduction.- 7.2 Creation and Modification of Solids with Surfaces.- 7.2.1 Defining surfaces by skinning.- 7.2.2 Defining surfaces by translating control points.- 7.2.3 Defining surface by interpolation.- 7.2.4 Defining surfaces by Boolean operations.- 7.3 Primitive Solid Generation.- 7.3.1 Creation of a parallelepiped and a cylinder.- 7.3.2 Creation of a rotational model.- 7.3.3 Creation of a mirror-image model.- 7.3.4 Creation of a skinning model.- 7.3.5 Creation of a sweep model.- 7.4 Local Modification Operations.- 7.4.1 Creation and modification of edges.- 7.4.2 Lifting operation.- 7.4.3 Model cutting.- 7.4.4 Model gluing.- 7.5 Programs of Local Operations.- 8 Boolean Operations.- 8.1 Introduction.- 8.2 Boolean Operations of Solids with Free-Form Surfaces and Their Problems.- 8.2.1 Intersection calculations.- 8.2.2 How to deal with intersection curves.- 8.3 Boolean Operation Algorithm in DESIGNBASE.- 8.3.1. Intersection calculations between edges and surfaces.- 8.3.2 Intersection calculations between surfaces.- 8.3.3 Creation of intersection vertices.- 8.3.4 Creation of intersection edges.- 8.3.5 Classification of boundaries and deletion of unnecessaryparts.- 8.3.6 Gluing of two solids.- 8.3.7 Examples of execution.- 9 Rounding Operation.- 9.1 Introduction.- 9.2 Problems with the Rounding Operation.- 9.3 Rounding Operation in DESIGNBASE.- 9.4 Example of Rounding Operation Execution.- 9.5 Algorithm of Rounding Operation.- 9.6 How to Calculate Trajectories Drawn by Tangent Points.- 10 Functions in Aiding Design.- 10.1 Introduction.- 10.2 Parametric Design.- 10.3 UNDO · REDO Operations.- 10.3.1 Interactive system.- 10.3.2 UNDO · REDO operations in DESIGNBASE.- 10.3.3 Representation of the solid creation process.- 10.3.4 UNDO · REDO with Boolean operations.- 10.4 Creation of Similar Shapes.- 10.4.1 Limits of the UNDO · REDO operations.- 10.4.2 Reexecution function.- 10.4.3 Limits of reexecution function.- 11 Rendering.- 11.1 Introduction.- 11.2 Color Components and Shading Model.- 11.2.1 Color representation.- 11.2.2 Ambient light.- 11.2.3 Diffuse reflection light.- 11.2.4 Specular reflection light.- 11.2.5 Transmission light.- 11.3 Z-Buffer Method.- 11.4 Scan Line Method.- 11.4.1 Characteristics of scan line method.- 11.4.2 Actual processing in the scan line method.- 11.4.3 Coherence in the scan line method.- 11.4.4 Antialiasing — A-buffer method.- 11.5 Ray Tracing Method.- 11.5.1 Antialiasing in the ray tracing method.- 11.6 Mapping Method.- 11.6.1 Significance of mapping.- 11.6.2 Texture mapping.- 11.6.3 Reflection mapping.- 11.6.4 Refraction mapping.- 11.6.5 Bump mapping.- 11.6.6 Solid texture.- 12 Mass Properties.- 12.1 Introduction.- 12.2 How to Obtain Surface Area.- 12.2.1 Monte Carlo method.- 12.2.2 Element subdivision method.- 12.2.3 Polygonization.- 12.2.4 Numerical integration.- 12.3 How to Obtain Volume, Center of Gravity, and Moment of Inertia.- 12.3.1 Monte Carlo method.- 12.3.2 Element subdivision method.- 12.3.3 Method using integration theorem.- 12.4 Mass Property Calculation in DESIGNBASE.- 13 3-Dimensional Modeling Method.- 13.1 Introduction.- 13.2 Resin Model Creation System.- 13.2.1 Fundamental principles.- 13.2.2 UV curing resin.- 13.2.3 Laser control.- 13.2.4 Data processing.- 13.3 Link with Modeler.- 13.3.1 Link with surface modeler.- 13.3.2 Link with solid modeler.- 13.4 DESIGNBASE and Resin Model Creation System.- 14 Solid Models and Structure Analysis.- 14.1 Introduction.- 14.2 History of Finite Element Method.- 14.3 Finite Element Method and Solid Models.- 14.4 3-Dimensional Mesh Generation.- 14.5 KSWAD — Integrated CAE System.- 14.5.1 How to apply data of solid modeler.- 14.5.2 Genuine automatic meshing.- 14.5.3 Mapped meshing.- 14.5.4 Examples of analyses by KSWAD.- References.

O autorze

The book on the next generation of CAD systems! It explains the features of a three-dimensional CAD system and its wide range of applications. It describes the concepts of solid models, and the theory of curves and surfaces and it illustrates these concepts through "real world" applications. This book is targeted at a readership in industry, particularly advanced CAD users, as well as in CAD research.