Smart Materials And Structures: New Research

✍ Scribed by Peter L. Reece

• Publisher: Nova Science Publishers
• Year: 2007
• Tongue: English
• Leaves: 304
• Edition: 1
• Category: Library

✦ Synopsis

'Smart' materials respond to environmental stimuli with particular changes in some variables. For that reason they are often also called responsive materials. Depending on changes in some external conditions, 'smart' materials change either their properties (mechanical, electrical, appearance), their structure or composition, or their functions. Mostly, 'smart' materials are embedded in systems whose inherent properties can be favourably changed to meet performance needs. Smart materials and structures have widespread applications in: Materials science - composites, ceramics, processing science, interface science, sensor/actuator materials, chiral materials, conducting and chiral polymers, electrochromic materials, liquid crystals, molecular-level smart materials, biomaterials; sensing and actuation - electromagnetic, acoustic, chemical and mechanical sensing and actuation, single-measurand sensors, multiplexed multimeasurand distributed sensors and actuators, sensor/actuator signal processing, compatibility of sensors and actuators with conventional and advanced materials, smart sensors for materials and composites processing; and, optics and electromagnetics - optical fibre technology, active and adaptive optical systems and components, tuneable high-dielectric phase shifters, tuneable surface control. It also have applications in: structures - smart skins for drag and turbulence control, other applications in aerospace/hydrospace structures, civil infrastructures, transportation vehicles, manufacturing equipment, repairability and maintainability; control - structural acoustic control, distributed control, analogue and digital feedback control, real-time implementation, adaptive structure stability, damage implications for structural control; and, information processing - neural networks, data processing, data visualisation and reliability. This book presents leading research from around the globe in this field.

✦ Table of Contents

SMART MATERIALS AND STRUCTURES: NEW RESEARCH......Page 5
NOTICE TO THE READER......Page 6
CONTENTS......Page 7
PREFACE......Page 9
1 Introduction......Page 13
2.1 Polarization Mechanism......Page 16
2.2 Electric Double Layers and Water Bridge Model......Page 19
2.3 Conduction Model......Page 20
3 Components of Electrorheological Fluids......Page 21
4 Design and Preparation of ER Materials......Page 23
4.1 ER Materials Based on Molecular and Crystal Structure Design......Page 24
4.2 ER Materials Based on Nanocomposite and Hybrid Design......Page 35
4.3 Molecular-Scale Organic/Inorganic Hybrids......Page 45
1.1 Introduction......Page 47
1.2 Working Principle of Self-Coupled ER Dampers......Page 48
1.3 The First Generation Product: Adaptive ER-piezoceramic Damper......Page 50
1.4 The Second Generation Product: Self-Coupled ER Damper......Page 54
2.1 Introduction......Page 62
2.2 Sound Tunable Characteristics of Flexible ER Layer [131]......Page 63
2.3 Vibration-Radiation Model of the ER Layer [134]......Page 68
Acknowledgements......Page 71
References......Page 72
Abstract......Page 79
1 Introduction......Page 80
2.1 Basic Equations......Page 81
2.2 Boundary Conditions......Page 83
3.1 General Solution......Page 85
3.2 Dielectric Crack Problems......Page 88
3.3 Electric Displacement at the Crack Surfaces......Page 92
3.4 Full Electroelastic Field in the Entire Piezoelectric Plane......Page 94
3.5 Asymptotic Crack-Tip Field......Page 99
4 Three-Dimensional Problems......Page 103
4.1 General Solution......Page 104
4.2 Dielectric Crack Problems......Page 106
4.3 Asymptotic Crack-Tip Field......Page 114
5 Fracture Criterion......Page 117
6 Conclusion......Page 119
References......Page 120
Abstract......Page 125
1 Introduction......Page 126
2 Extension and Shear Actuations......Page 127
2.1 Basic Equations and Weak Formulation......Page 128
2.2 Constitutive Models......Page 130
2.3 Electric Field to Potential Relations......Page 137
2.4 Finite Element Formulation for Hybrid Actuated Beam......Page 138
3 Bending and Free Vibration Behaviour of Smart Sandwich Beams......Page 142
3.1 Bending Behaviour of Hybrid Actuated Sandwich Beams......Page 145
4 Distributed Active Vibration Control......Page 149
4.1 Active Control Strategies......Page 150
4.2 State-Space Formulation......Page 151
4.3 Modal Control......Page 154
4.4 Condensation of System Matrices......Page 156
4.5 Pole Placement and Mode Shape Control......Page 158
4.6 Active Vibration Control and Modal Response Analysis......Page 159
4.7 Pole Placement and Mode Shape Control......Page 163
References......Page 167
1 Introduction......Page 171
2.1 Admittance Analysis......Page 173
2.2 Shunt Performance......Page 178
3.1 Shunt Circuit Design......Page 180
3.2 Sensitivity Analysis......Page 183
3.3 Shunt Performance......Page 185
References......Page 187
Abstract......Page 189
Introduction......Page 190
Piezoelectric Constitutive Relations......Page 192
Existing PZT-Structure Interaction Models......Page 193
Effective Mechanical Impedance and Associated Modelling......Page 197
System Parameter Identification From Extracted Impedance Spectra......Page 206
Damage Diagnosis of Aerospace and Mechanical Systems......Page 211
Extension to Damage Diagnosis of Civil-Structural Systems......Page 214
Concrete Strength Prediction Using Emi Technique......Page 218
Damage Assessment of Concrete Using Emi Technique......Page 221
(a) Establishment of Impedance-Based Damage Model for Concrete......Page 225
Statistical Analysis of Damage Variable for Concrete......Page 227
Computation of Fuzzy Failure Probability......Page 229
Monitoring Concrete Curing Using Extracted Impedance Parameters......Page 231
Practical Issues Related To EMI Technique......Page 234
Conclusions......Page 236
References......Page 237
Abstract......Page 241
1 Introduction......Page 242
2 An Overview of Multi-layer Neural Networks and Back-propagation Algorithm......Page 244
3.1 General Methodology......Page 247
3.2 Numerical Illustration......Page 250
3.3 Statistic Performance and Its Robustness......Page 255
4.1 Basic Methodology......Page 258
4.2 Reference Structural Model and Motion Equation under Dynamic Excitation......Page 260
4.3 ENN for Nonparametric Modeling of the Reference Structural Model......Page 262
4.4 PENN for Stiffness and Damping Coefficients Identification......Page 265
4.5 Noise Effects......Page 268
5 Concluding Remarks......Page 270
References......Page 272
Abstract......Page 275
1 Introduction......Page 276
2 Modified Elman Network......Page 277
3 Improved Particle Swarm Optimization (IPSO)......Page 280
4 IPSO-Based Learning Algorithm of Elman Network......Page 282
5 Speed Identification of USM Using the IPSO-Based Elman Network......Page 283
6 Speed Control of USM Using the IPSO-Based Elman Network......Page 288
7 Conclusions......Page 291
Appendix A......Page 292
References......Page 293
INDEX......Page 297