Computer-Aided Design Engineering and Manufacturing Systems Techniques and Applications

MANUFACTURING SYSTEMS PROCESSES......Page 1
Preface......Page 5
Editor......Page 6
Contributors......Page 7
Contents......Page 8
1 - Analysis and Synthesis of Engineering Surfaces in Bridge Manufacturing and Design......Page 9
Relation to Precision Surfaces......Page 10
A Vision for “Fingerprinting” Manufactured Surfaces......Page 11
Design Techniques Based on Artificial Intelligence......Page 12
Spectral-Based Characterization Methods......Page 14
Variational Formulation and Finite Element Discretization......Page 15
Forming Sequence Design and Die-stress Analysis for Pressure-assisted Injection Forging of Thick-walled Tubes......Page 16
Literature Background: Fractals......Page 17
Forging Optimization Problem......Page 18
Splines and Bsplines......Page 19
Appendix D......Page 20
Fractal Parameter Computation......Page 21
Calculation of ................Page 22
Experimental Layout......Page 23
Experimental Design and Conditions......Page 24
Mesh Refinement......Page 26
Synthesis and Comparison......Page 27
5.6 Conclusion......Page 28
Vibration Force with Synthesized Profiles......Page 29
Philosophy......Page 30
Literature Background......Page 31
Mathematical Background......Page 32
Karhunen-Loève Transform for Surface Analysis......Page 33
Simple Linear Functions......Page 34
General Multi-Component Functions......Page 35
Monitoring Decomposed Functions in Signals......Page 37
Monitoring and Prediction of Numerically Generated Surface Signals......Page 38
Example One: Decomposition of Multi-Component Signals......Page 39
Example Two: Detection of Nonstationary Patterns......Page 41
Understanding and Redesigning a Manufacturing Process through Surface Analysis......Page 43
Dichotomy or Integration?......Page 46
Conjunction of the Two Methods......Page 47
Acknowledgments......Page 49
References......Page 50
3.2 Grinding Process......Page 54
2.2 Traditional Manual Tolerance Charting......Page 56
Matrix Approach......Page 58
4.2 FEM and Applications in Metal-Forming......Page 61
Forging Simulation......Page 66
Simplex Optimization Algorithm......Page 67
6.6 Prototype Case Study Analyses of Welds......Page 68
Numerical Simulation of the Forging Process......Page 69
Analysis of Billet Stability......Page 70
3.1 Introduction......Page 72
Control Issues Relevance......Page 73
History and Perspective......Page 74
Grinding Wheels Materials......Page 75
Theoretical Models......Page 76
Force Models......Page 80
Component Forms......Page 81
Grinding Process Model Development for Estimation......Page 82
6.4 Theoretical Foundation of the Geometric-Constraints Method......Page 84
Multiple Input Estimation Approach......Page 85
6.5 Some Properties Associated with Geometric Constraints......Page 87
Simulation of the Folding of Material During Injection Forging......Page 88
3.6 Force Measurement......Page 90
System Architecture: Parallel Processing and Implementation......Page 92
FE Modeling Procedures......Page 93
3.9 Summary......Page 71
Preform Design for Injection Forging......Page 97
Folding Defects......Page 99
Nomenclature......Page 104
Process Configurations......Page 105
Injection Forging of Solid Billet......Page 106
Modeling Requirement......Page 65
5.1 Introduction......Page 113
Basic Design Techniques......Page 86
Simulation of Buckling During Injection Forging......Page 114
Finite Difference Gradients......Page 117
Injection Forging of Tubular Materials......Page 94
Problem Equations......Page 95
Remeshing and Transfer of State Variables......Page 131
Prescribed Shape......Page 133
Derivation of Weighted Finite-Sum Representation of Pseudo Steady State Based on Rosenthal Solution......Page 100
References......Page 137
5 - Optimal Design Techniques in Non- Steady-State Metal Forming Processes......Page 141
Backward Tracing Method......Page 148
Design Techniques Based on Optimization Methods......Page 89
Analytical Approximation of the Objective Function......Page 150
Variational Differentiation Methods......Page 153
5.3 The Optimization Problem......Page 155
Contact Algorithm and Time Integration......Page 158
Incremental Mass Conservation......Page 159
Objective Function, Regularization Functions, and Constraints......Page 162
Metallurgical Aspects......Page 165
5.4 Sensitivity Analysis–Optimization Method......Page 101
Optimization Problem......Page 168
Non Steady-State Extension of the Adjoint Method......Page 102
Discrete Direct Method......Page 171
Incremental Calculation of the Basic Derivatives......Page 172
Accuracy of the Derivatives......Page 175
Incremental Mass Conservation......Page 176
Shape Optimization of the Initial Billet......Page 180
Shape Optimization of an Extrusion Die......Page 182
Preform Shape Optimization for a Two-Step Forging Sequence......Page 183
Preform Shape Design for a Two-Step Forging Sequence......Page 185
Optimal Design Techniques in Non-Steady-State Metal Forming Processes......Page 190
References......Page 191
6 - Analysis of Welds Using Geometric Constraints......Page 195
6.1 Introduction......Page 77
6.2 Physical Model of Welding Process......Page 78
6.3 Discussion of Mathematical Issues......Page 197
6.7 Implicit Representation of Temperature Dependence of Material Properties......Page 222
6.8 Implicit Representation of Coupling Between Heat Transfer and Fluid Convection......Page 226
6.9 Conclusion......Page 130
Welding Parameters for Data Set 1:......Page 229
Welding Parameters For Data Set 2:......Page 230
Semi-Quantitative Proof of Validity of Elliptic-Equation Representation of Temperature Fields Defined within Subdomains Having Constrained Surfaces......Page 231
7.1 Introduction......Page 233
7.3 Control System Requirements......Page 234
7.4 Arc Welding as a Multivariable Process......Page 235
7.5 Traditional Approaches to Arc Welding Modeling and Control......Page 236
7.6 Neural Networks......Page 238
Equipment Setpoint Selection Using the Back Propagation Network......Page 241
Real-Time Monitoring of Weld Joint Penetration......Page 243
Dynamic Representation of Resistance Spot Welding Process Input/Output Relationships......Page 244
Closed-Loop Control of GTA Weld Bead Geometry......Page 245
Process Modeling......Page 246
Process Control......Page 247
Weld Bead Profile Analysis and Control......Page 248
References......Page 251