Contents
List of Figures……………………………………………………………………………………………xv
Preface…………………………………………………………………………………………………… xxix
Acknowledgements………………………………………………………………………………. xxxi
Authors………………………………………………………………………………………………..xxxiii
1. Wearable Electronics……………………………………………………………………………1
1.1 Introduction………………………………………………………………………………..1
1.2 Textiles and Information Processing……………………………………………2
1.3 Chronology of Wearable Electronics……………………………………………3
1.4 Application Groups……………………………………………………………………..5
1.4.1 Retailer Support………………………………………………………………5
1.4.2 Service Support……………………………………………………………….5
1.4.3 User Convenience……………………………………………………………5
1.4.4 User Interfacing……………………………………………………………….5
1.4.5 Appliance Networking……………………………………………………6
1.4.6 Networking with External Networks………………………………6
1.5 Need for Wearable Electronics…………………………………………………….6
1.5.1 Health and Wellness Monitoring…………………………………….7
1.5.2 Safety Monitoring……………………………………………………………8
1.5.3 Home Rehabilitation……………………………………………………… 10
1.5.4 Assessment of Treatment Efficacy…………………………………. 11
1.6 Textile Fibres Used for Wearable Electronics Applications……….. 13
1.7 Sensing Fabrics…………………………………………………………………………. 15
1.7.1 Wearable Sensor on Knitted Fabrics……………………………… 17
1.7.2 Fabric Electrodes Realized by Flat-Knitting Technology……………….. 17
1.7.3 Fabric Electrodes Realized by Seamless Knitting Technology…………… 17
1.7.4 Bioelectrical Signals through Fabric Electrodes…………….. 17
1.7.5 Knitted Piezoresistive Fabric Realized by Seamless Knitting Technology
1.7.6 Printed Piezoresistive Fabric Manufactured by Serigraphy Technology
1.7.7 Fabric Strain Sensors…………………………………………………….. 19
1.7.8 Biomechanical Signals through Fabric Strain Sensors…… 19
1.8 Wearable Sensors………………………………………………………………………20
1.8.1 Electrode Technologies………………………………………………….26
1.8.1.1 Dry Electrodes…………………………………………………26
1.8.1.2 Non-Contact, Capacitive Electrodes…………………28
1.8.1.3 Skin-Electrode Modelling………………………………..30
1.8.2 Body Sensor Network…………………………………………………… 32
1.8.2.1 Anatomy of a Body Sensor Network………………..34
1.8.2.2 BSNs versus Wireless Sensor Networks…………..34
1.8.2.3 Wearability………………………………………………………34
1.8.2.4 Technical Challenges……………………………………….35
1.8.2.5 Practical Design Considerations………………………35
1.8.3 Wireless Body Area Sensor Network: Health Monitoring………..36
1.8.3.1 System Architecture…………………………………………38
1.8.3.2 Communication Protocol and Time
Synchronization………………………………………………42
1.8.3.3 Graphical User Interface…………………………………..43
1.8.3.4 Sensor Node Identification, Association
and Calibration………………………………………………..43
1.8.3.5 Event Processing………………………………………………44
1.9 Biomonitoring Devices………………………………………………………………46
1.10 Interfacing Circuits and Garments…………………………………………….47
1.10.1 Communication between Circuits and Garments………….48
1.10.2 Patient Monitoring: Networks of Wireless Intelligent
Sensors………………………………………………………………………….. 52
1.10.3 Telemedical System………………………………………………………..53
1.10.4 Wireless Intelligent Sensor Wise……………………………………54
1.10.5 Applications…………………………………………………………………..54
1.10.6 Software Development…………………………………………………..55
1.10.7 Power System………………………………………………………………… 57
1.11 Future Research Scope………………………………………………………………60
1.11.1 Next Stage in Man–Machine Interaction……………………….. 62
1.11.1.1 Thermo-Generator for Harvesting Electric
Power from Body Heat……………………………………. 62
1.11.1.2 Interwoven Antenna for a Transponder System in Textile Fabric…………. 62
1.11.1.3 Fault-Tolerant Integration of
Microelectronics in Smart Textiles…………………..64
1.12 Summary………………………………………………………………………………….. 67
Bibliography………………………………………………………………………………………. 67
2. Textile Fabric Development for Wearable Electronics………………………79
2.1 Introduction: Core Spun Yarn Production Methods………………….79
2.1.1 Friction Spinning…………………………………………………………..79
2.1.1.1 Principle of Friction (DREF-3) Spinning
Systems…………………………………………………………80
2.1.1.2 Fibres Integration……………………………………………. 81
2.1.1.3 Twist Insertion…………………………………………………82
2.1.1.4 Twist Insertion in Core-Type Friction
Spinning……………………………………………………….82
2.1.1.5 Yarn Structure………………………………………………….82
2.1.1.6 Advantages of Friction Spinning System…………82
2.1.1.7 Limitations of Friction Spinning System………….83
2.1.2 Wrap Spinning………………………………………………………………83
2.1.2.1 Wrap Spun Yarn Production Method……………….83
2.1.2.2 Operating Principle………………………………………….84
2.2 Development of Cotton-Wrapped Nichrome Yarn…………………….85
2.2.1 Development of Woven Fabric Embedded with
Cotton-Wrapped Nichrome Yarn
2.2.2 Integration of Nichrome Wire-Embedded Cotton
Fabric in Knitted Fabric
2.2.3 Testing of Thermal Conductivity and Nichrome
Wire Resistance……………………………………………………………..88
2.2.4 Testing of Nichrome Wire Resistance…………………………….89
2.3 Development of Copper Core Yarn and Fabric…………………………..89
2.3.1 Development of Copper Core Yarn………………………………..89
2.3.2 Development of Copper Core Conductive Fabric………….. 91
2.3.3 Testing of Copper Core Conductive Yarn and Fabric……..93
2.3.3.1 Structural Parameters of Copper Core
Cotton Sheath Conductive Yarn……………………….93
2.3.3.2 Tenacity……………………………………………………………94
2.3.3.3 Breaking Elongation………………………………………..95
2.3.3.4 Multivariable ANOVA……………………………………..96
2.3.3.5 Electrical Properties…………………………………………97
2.3.3.6 Electromagnetic Shielding Effectiveness………….97
2.3.4 Industrial Importance……………………………………………………98
2.4 Development of POF Fabric……………………………………………………….99
2.4.1 Development of Optical Core Conductive Yarn……………..99
2.4.2 Development of Communication Fabric Using
Optical Core Conductive Yarn
2.4.3 Testing of Communication Fabric……………………………….. 101
2.4.4 Testing of Communication Fabric to Assess Physical
Characteristics…………………………………………………………….. 102
2.4.5 Testing of Communication Fabric to Assess
Signal-Transferring Capability
2.5 Development of POF Yarn………………………………………………………. 104
2.5.1 Development of Illuminated Fabric…………………………….. 104
2.5.2 Characteristics Analysis of PMMA POF Filament………. 104
2.5.3 Influence of Weave Geometry on Illumination……………. 105
2.5.4 Influence of LED Colours on Power Consumption
in Illuminated Fabric Samples
2.6 Development of Yarn for Teleintimation Fabric………………………. 108
2.6.1 Development of Teleintimation Fabric Using the
Sequential Technique
2.6.2 Development of Teleintimation Fabric by
Power Loom……………………………………………………………110
2.6.3 Development of Teleintimation Fabric Using
Handloom…………………………………………………………………… 113
2.6.4 Physical Characteristics of Teleintimation Fabric………… 114
2.6.4.1 Bending Rigidity…………………………………………… 114
2.6.4.2 Tensile Strength…………………………………………….. 115
2.6.4.3 Air Permeability……………………………………………. 116
2.6.5 Testing of POF Filament for Teleintimation Fabric………. 117
2.6.6 Electrical Testing of Teleintimation Fabric…………………… 118
2.6.6.1 Testing of POF with IRF14F Optical Receiver……..119
2.6.7 Signal-Transferring Efficiency of Teleintimation
Fabrics………………………………………………………………….. 120
2.6.8 SEM Analysis of Teleintimation Fabric………………………… 123
2.7 Summary………………………………………………………………………………… 124
Bibliography…………………………………………………………………………………….. 126
3. Design of Circuits and Integration into Wearable Fabrics…………….. 131
3.1 Introduction……………………………………………………………………………. 131
3.2 Microelectronics for Smart Textiles…………………………………………. 132
3.2.1 System Overview………………………………………………………… 133
3.2.2 Interconnect Technology between Textiles and
Electronics…………………………………………………………………… 134
3.3 Flexible Wearable Electronics………………………………………………….. 138
3.3.1 Textiles and Clothing as Flexible Supports………………….. 139
3.3.1.1 Flexible Strain Sensors…………………………………… 140
3.3.1.2 Detection of Posture and Movement……………… 140
3.3.1.3 Biometric Measurements……………………………….. 141
3.3.1.4 Location Monitoring……………………………………… 142
3.3.1.5 Pressure Sensors……………………………………………. 142
3.3.1.6 Ballistic Penetration and Fabric Damage……….. 143
3.3.1.7 Actuators and Output Signals……………………….. 143
3.3.1.8 Data Management and Communication……….. 144
3.4 Wearable Motherboard……………………………………………………………. 148
3.4.1 Need for a Technology Solution………………………………….. 149
3.4.2 Design and Development of the Wearable
Motherboard……………………………………………………………….. 149
3.4.2.1 Performance Requirements…………………………… 149
3.4.2.2 GTWM Design and Development
Framework………………………………………………….. 150
3.4.2.3 Production of GTWM……………………………………. 151
3.4.2.4 Testing of GTWM………………………………………….. 153
3.4.2.5 Wearable Motherboard as a Universal
Interface………………………………………………………… 154
3.5 Vital Signs Monitoring……………………………………………………………. 157
3.6 Voice Monitoring…………………………………………………………………….. 158
3.7 Design of Heat-Generating Circuit for Nichrome Fabric…………. 159
3.7.1 Operation of Heat-Generating Circuit…………………………. 160
3.8 Design of Communication Circuit for Copper Core
Conductive Fabric
3.8.1 Temperature Measurement Circuit for Copper Core
Conductive Fabric
3.9 Design of Signal-Transferring Circuit for Optical Core
Conductive Fabric
3.10 Development of Illuminated System for POF Fabric……………….. 165
3.10.1 Design of Illuminated System……………………………………… 166
3.11 Design of Bullet Wound Intimation Circuit for
Teleintimation Fabric
3.11.1 Circuits Using 8 × 8 Matrix Format……………………………… 167
3.11.2 Circuit Using 64 × 64 Matrix Format…………………………… 168
3.11.3 Circuit Using SMD Components…………………………………. 169
3.11.4 Circuits Using PIC Microcontroller with
Detachable Circuits……………………………………………………… 169
3.11.5 Circuits Using Flexible PCB………………………………………… 171
3.11.6 Method of Bullet Count………………………………………………. 172
3.11.7 Bullet Location and Bullet Count Technique……………….. 173
3.11.8 Problems Faced in Detecting the Bullet Location………… 173
3.12 Circuits for Smart Shirt…………………………………………………………… 173
3.12.1 Circuits for Body Temperature Measurement……………… 173
3.12.2 Circuits for Pulse Rate Measurement………………………….. 174
3.12.3 Circuits for Respiration Rate Measurement…………………. 176
3.12.4 Circuits for Telemonitoring System…………………………….. 176
3.12.4.1 4RS232 Communication Unit………………………… 176
3.12.4.2 Mobile Phone (MODEM)……………………………….. 178
3.13 Future Research Scope……………………………………………………………. 178
3.14 Summary………………………………………………………………………………… 184
Bibliography…………………………………………………………………………………….. 185
4. Product Development Using Wearable Electronic
Integrated Fabrics……………………………………………………………………………. 193
4.1 Introduction……………………………………………………………………………. 193
4.2 Heating Garment……………………………………………………………………. 193
4.2.1 Performance Analysis of Heating Garment…………………. 194
4.3 Development of Communication Garment Using Copper
Core Conductive Fabric…………………………………………………………… 195
4.3.1 Performance Analysis of Communication Garment
Using Copper Core Conductive Fabric………………………… 196
4.3.2 Development of Communication Garment Using
Optical Core Conductive Fabric…………………………………… 199
4.3.2.1 Performance Analysis of Communication
Garment Using Optical Core Conductive
Fabric…………………………………………………………….. 199
4.4 Development of Illuminated Garment……………………………………. 201
4.5 Development of Teleintimation Garment…………………………………203
4.5.1 Detection of Bullet Wound in Teleintimation
Garment…………………………………………………………………… 206
4.5.2 Performance Analysis of Teleintimation Garment
Using DAQ Card…………………………………………………………. 207
4.5.3 Testing of Circuits Developed for 64 × 64 Matrix
Format………………………………………………………………………….208
4.5.4 Testing of Circuits Developed Using PIC
Microcontroller with Detachable PCBs………………………..209
4.5.5 Testing of Circuits Developed Using PIC
Microcontroller with Flexible PCBs…………………………….. 210
4.6 Smart Shirt……………………………………………………………………………… 212
4.6.1 Measurement of Vital Signs………………………………………… 212
4.6.1.1 Wearable Electrocardiograph………………………… 212
4.6.1.2 ECG Shirt………………………………………………………. 217
4.6.1.3 Electroencephalography (EEG)………………………226
4.6.1.4 Future Research Scope: EEG and ECG……………228
4.6.2 Electronic Shirt…………………………………………………………….234
4.6.2.1 Smart Shirt: Temperature Measurement………..234
4.6.2.2 Measurement Concept……………………………………236
4.6.2.3 Hybrid Fabric Sensor……………………………………..236
4.6.2.4 Electronic Measurement Circuit……………………. 237
4.6.2.5 Measurement Principle…………………………………. 237
4.6.2.6 Theoretical Temperature Accuracy………………..238
4.6.2.7 Temperature Measurements………………………….. 239
4.6.2.8 Temperature Measurement Accuracy……………. 240
4.6.2.9 Surface Temperature Profile………………………….. 241
4.6.2.10 Measurement Ambiguity Avoidance…………….. 242
4.7 E-Textile Craft…………………………………………………………………………. 246
4.7.1 Techniques for E-Textile Craft……………………………………… 248
4.7.1.1 Laser-Cut Fabric PCBs…………………………………… 248
4.7.1.2 Hand-Cut Fabric PCBs…………………………………… 251
4.7.1.3 Electronic Sequins………………………………………….253
4.7.1.4 Socket Buttons……………………………………………….255
4.7.1.5 Insulators………………………………………………………. 257
4.8 Future Research Scope…………………………………………………………….260
4.9 Summary………………………………………………………………………………… 260
Bibliography…………………………………………………………………………………….. 262
5. Software Development for Wearable Electronics…………………………… 271
5.1 Introduction……………………………………………………………………………. 271
5.2 Biosensor Design and MEMS Integration……………………………….. 271
5.2.1 Pervasive Monitoring………………………………………………….. 272
5.2.2 Body Sensor Networks………………………………………………… 272
5.2.3 BSN Architecture………………………………………………………… 273
5.2.4 UbiMon………………………………………………………………………. 274
5.3 Health-Care Monitoring System……………………………………………… 275
5.3.1 System Architecture…………………………………………………….277
5.3.2 Body Sensor Networks: Technical Challenges…………….. 279
5.4 Wireless Sensor Networks for Health Monitoring……………………280
5.5 Wearable and Wireless Brain–Computer Interface………………….. 281
5.5.1 Dry MEMS Electrodes and Electrode Holders…………….. 282
5.5.2 Data Acquisition Unit…………………………………………………..283
5.5.3 Wireless Transmission Unit…………………………………………283
5.5.4 Real-Time Digital Signal Processing Unit…………………….284
5.5.5 Data Logging and Digital Signal Processing on
a Cell Phone…………………………………………………………………284
5.5.6 Wet Electrodes……………………………………………………………..285
5.5.7 Placement of Electrode………………………………………………… 287
5.5.8 MEMS-Based Dry Electrodes………………………………………. 289
5.5.9 Wireless EEG System……………………………………………………290
5.6 Brain–Computer Interface………………………………………………………. 291
5.6.1 Wearable Brain Cap…………………………………………………….. 293
5.6.2 Fabrication Technique…………………………………………………. 293
5.6.3 Contactless Sensor Design…………………………………………… 294
5.6.3.1 Measurements and Analysis…………………………. 294
5.6.3.2 Brain Activity Electric Field…………………………… 295
5.6.3.3 Electroactive Properties of the Hydrogel……….. 295
5.7 Soldier’s Status Monitoring Software Using Visual Basic……….. 295
5.7.1 Soldier’s Status Monitoring Software………………………….. 296
5.7.2 Location Evaluation of Bullet Wound Intimation………… 298
5.8 Soldier’s Status Monitoring Software Using LabVIEW…………….300
5.8.1 LabVIEW……………………………………………………………………..300
5.8.2 Implementation of LabVIEW-Based SSM Software……… 301
5.8.3 Integration of Teleintimation Garment and SSM
Software……………………………………………………………………… 301
5.8.4 Soldier’s Status Monitoring Software…………………………..302
5.8.5 Server Operation………………………………………………………….302
5.8.6 Location Evaluation Using LabVIEW-Based SSM
Software………………………………………………………………………303
5.9 Communication System between Garment and SSM
Software………………………………………………………………………….. 304
5.10 GPRS-Based Soldier-Tracking System………………………………………305
5.10.1 Schematic Diagram of Soldier-Tracking System…………..306
5.10.2 Methodology for Soldier-Tracking System……………………307
5.10.3 Hyper-Terminal Testing of AT Commands…………………. 311
5.11 Future Research Scope……………………………………………………………. 315
5.12 Summary………………………………………………………………………………… 316
Bibliography…………………………………………………………………………………….. 317
6. Design and Development of Flexible Solar Cell’s Integration
in Clothing………………………………………………………………………………………. 325
6.1 Introduction……………………………………………………………………………. 325
6.2 Electronic Display Technologies……………………………………………… 325
6.3 Capacitive Sensing Fabrics and Garments………………………………. 328
6.4 Solar Cell Embedded on Clothing……………………………………………330
6.5 Flexible Solar Cell Technologies……………………………………………… 332
6.5.1 Flexible a-Si and pc-Si Cells………………………………………….334
6.5.2 Single-Crystalline Si Transfer Technique…………………….. 337
6.5.3 Photovoltaic Thin-Film Cells into Wearables………………. 339
6.5.4 Protocrystalline Silicon Cells………………………………………. 341
6.5.5 Energy Yield………………………………………………………………..342
6.6 Clothing-Integrated Photovoltaics……………………………………………343
6.7 Integration of Garment and Solar Panel…………………………………..348
6.7.1 Flexible Solar Cells……………………………………………………….355
6.7.2 Battery…………………………………………………………………………355
6.7.3 Charge Controller………………………………………………………..356
6.7.4 Inverter………………………………………………………………………..356
6.8 Integration of Tent and Solar Cells…………………………………………..356
6.8.1 Stitching of Flexible Solar Cells……………………………………356
6.8.2 Fusing of Flexible Solar Cells………………………………………. 357
6.9 Finishing and Integration of Flexible Solar Array…………………… 359
6.10 Testing of Flexible Solar Cell……………………………………………………360
6.11 Testing of Charge Controller……………………………………………………363
6.12 Testing of Inverter……………………………………………………………………364
6.13 Testing of Cloth-Integrated Flexible Solar Cells……………………….365
6.14 Integration and Testing……………………………………………………………365
6.15 Solar Jacket……………………………………………………………………………… 367
6.16 Future Research Scope…………………………………………………………….368
6.17 Summary…………………………………………………………………………………368
Bibliography…………………………………………………………………………………….. 369
7. Garment-Integrated Wearable Electronic Products………………………… 375
7.1 Introduction……………………………………………………………………………. 375
7.2 Wearable Mobihealth Care System………………………………………….. 375
7.2.1 Development of the Wearable Shirt…………………………….. 378
7.2.2 Development of the PPU……………………………………………… 381
7.2.3 Development of Wireless Communication…………………..383
7.3 Smart Clothes for Ambulatory Remote Monitoring…………………385
7.3.1 Display Terminal Subsystem………………………………………. 387
7.3.2 Testing and Evaluations………………………………………………. 387
7.4 Development of Electronic Jerkin…………………………………………….388
7.4.1 Module I: Audio Module……………………………………………..388
7.4.2 Module II: Multimedia Module……………………………………388
7.4.3 Module III: Flexible Keypad Module…………………………… 389
7.4.4 Textile Integration……………………………………………………….. 389
7.4.5 Power Supply………………………………………………………………. 391
7.5 Smart Textile Applications………………………………………………………. 392
7.5.1 MP3 Jacket…………………………………………………………………… 392
7.5.2 Smart Carpet………………………………………………………………. 393
7.6 Development of Heating Gloves……………………………………………… 396
7.7 Development of Pneumatic Gloves…………………………………………. 397
7.7.1 Synthetic Rubber…………………………………………………………. 398
7.7.2 Lycra……………………………………………………………………………. 398
7.7.3 Rexine Material…………………………………………………………… 399
7.7.4 Pressure Regulator Assembly……………………………………… 399
7.7.5 Pneumatic Instruments………………………………………………..400
7.7.6 Pneumatic Gloves……………………………………………………….. 401
7.8 Gloves and Mobile Device: Product Design……………………………..404
7.8.1 Concept Development………………………………………………….405
7.8.2 Product Design…………………………………………………………….406
7.9 Future Research Scope…………………………………………………………….407
7.10 Summary…………………………………………………………………………………408
Bibliography……………………………………………………………………………………..409
Index