Sensors (eBook)

Contents 5
Guest Editorial 8
List of Contributors 15
Electromagnetic Sensors 19
Modern CMOS Hall Sensors with Integrated Magnetic Concentrators 20
1 HallEffect andHallElement 20
2 Contactless Magnetic Position Measurement 21
3 Multi-Axis Sensing 22
4 Integrated Magnetic Concentrator 23
5 IMCProcess 25
6 Magnetic andGeometric Properties of the IMC Layer 26
6.1 IMCMaterial Properties 26
6.2 IMCGeometric Properties 28
7 Saturation 29
8 Hysteresis 30
9 Sensor Architecture 31
10 Angular Position Sensor 33
11 Linear Position Sensor 34
12 Contactless Joystick Sensor 35
13 ElectricalCurrent Sensor 35
14 Electronic Compass 36
References 37
Commercial Magnetic Sensors (Hall and Anisotropic Magnetoresistors) 39
1 Introduction 39
2 Hall Sensor Design 40
3 AMR (Anisotropic Magneto-Resistive) Sensors 44
4 AMR Model 46
5 Future Progress 57
References 58
Improving the Accuracy of Magnetic Sensors 60
1 Introduction 60
2 Temperature Stability 60
2.1 Hall Sensors 61
2.2 Magnetoresistors 62
2.3 Fluxgate Sensors 62
2.4 GMI Sensors 63
2.5 Proton Magnetometer 64
3 Linearity 64
3.1 How to Measure the Linearity 65
4 Crossfield Effect 66
4.1 AMR 66
4.2 Fluxgate 69
5 Noise 70
5.1 How to Measure Noise Values 71
6 Perming Effect 72
7 Remarks on Digitalization 73
8 Peculiarities of Current Sensors 73
9 Peculiarities of Position Sensors 74
References 74
Modelling Electromagnetic Field Sensors 76
1 Introduction 76
2 Modelling PlaneWave Propagation 77
3 Differential Equation Methods 78
4 Integral Equation Methods 79
5 An Example Integral Equation Solution 80
6 Basis Functions 84
7 Cell Shape and Size 86
8 Wavelength Considerations 87
9 Convergence and Execution Considerations 87
10 Proximity Compensation 88
11 Conclusion 88
References 88
Dielectric Characterization of Biological Tissues: Constraints Related to Ex Vivo Measurements 90
1 Introduction 90
2 Metrological Aspects of Bioimpedance Spectroscopy 92
3 Measurement Constraints Related to the Bioimpedance Sensor 93
4 Measurement Constraints Related to the Biological Tissue Sample 94
5 Examples of Ex Vivo Results 95
6 Measurements on Human Blood 95
7 Ex Vivo Results 96
7.1 Discussion 96
7.2 Modelization Approach for Dielectric Characterization 97
8 Simulation 98
8.1 Discussion 99
9 Measurements on Anisotropic Medium 99
9.1 Electrodes Configuration 101
10 Ex Vivo Results 101
10.1 Relation Between the Permittivity and the Conductivity 101
11 Discussion on Bone Anisotropy Measurements at Low Frequency 101
12 Conclusion 103
References 103
Estimation of Property of Sheep Skin to Modify the Tanning Process Using Interdigital Sensors 106
1 Introduction 106
2 Motivation 107
3 Operating Principle of Interdigital Sensors 108
4 Processing of Sheep Skin 111
5 Experimental Setup 112
6 Preliminary Experimental Results 113
7 Interfacing and Development of an Embedded Controller Based Sensing System 116
8 Experiments with Sheep Skins and Results 118
9 Conclusion 123
References 123
Fiber Optic/Optical Fibre Sensors 126
Fiber Bragg Gratings Evanescent Wave Sensors: A View Back and Recent Advancements 127
1 Introduction 127
2 Fiber Bragg Gratings Hystory 128
3 Fiber Bragg Gratings as Sensors 133
4 FBGs EvanescentWave Sensors 136
4.1 FBGs Written in D-shaped Optical Fibers 137
4.2 Thinned FBGs (ThFBGS) 142
4.3 Tilted FBGs 151
4.4 Micro-Structured FBGs 153
4.5 Coated FBGs Based on Chemo-Mechanical and Chemo- Thermal Effects 160
5 Perspectives and Challenges 160
References 162
Optical Fibre Humidity Sensors Using Nano- films 167
1 Introduction 167
2 Humidity Sensing Materials and Deposition Techniques 169
2.1 Nanostructured Films 170
3 Optical Techniques Used In Fibre Optic Humidity Sensors 172
3.1 Reflective Sensors Based on Coating Deposition on the Tip of the Fibre 172
3.2 Transmissive Evanescent Wave Sensors 176
4 Conclusions 187
References 187
Overview of the OPTO-EMI-SENSE Project: Optical Fibre Sensor Network for Automotive Emission Monitoring 192
1 Introduction 193
2 Theoretical Background 194
3 Experimental Results 196
3.1 Gas Measurement in the Mid Infra Red Range 196
3.2 Gas Measurement in the Ultra Violet Range 200
3.3 Optical Fibre Temperature Measurement 206
4 Conclusions 208
References 209
Wireless Sensors 210
Wireless Sensor Networks and Applications 211
1 Introduction 211
2 Low-Rate Wireless Communication Technology 212
3 WSN Fundamentals 214
3.1 Network Topology 214
3.2 Routing Protocols 215
3.3 Data Integration Modes 216
4 WSN Architectures 217
4.1 Tier-based Architectures 217
4.2 Cluster-based Architectures 220
5 WSN Applications 222
5.1 WSN Applications Supporting Static Routing 223
5.2 WSN Applications Supporting Dynamic Routing 226
6 Conclusions 229
References 229
Wireless Sensor Network Transport Layer: State of the Art 232
1 Introduction 233
1.1 Relevant Terminologies 234
2 Major Transport Layer Protocols 239
2.1 COngestion Detection and Avoidance(CODA) 240
2.2 Event-to-Sink Reliable Transport (ESRT) 241
2.3 Reliable Multi-Segment Transport (RMST) 242
2.4 Pump Slowly Fetch Quickly (PSFQ) 243
2.5 GARUDA 243
2.6 Tiny TCP/IP 244
2.7 Sensor TCP(STCP) 245
2.8 SenTCP 246
2.9 Trickle 246
2.10 FUSION 247
2.11 Asymmetric and Reliable Transport (ART) 247
2.12 Congestion Control and Fairness (CCF) 248
2.13 Priority-based Congestion Control Protocol (PCCP) 249
2.14 Siphon 251
2.15 Reliable Bursty Convergecast (RBC) 251
2.16 RAP 252
3 Conclusion 254
References 255
Sensors for Tracking and Navigation 257
Real Time Tracking and Monitoring of Human Behavior in an Indoor Environment 258
1 Introduction 259
2 Motivation and Objectives 260
3 Fiber Grating and its Operational Principles 261
4 The FG Based 3D Vision Sensor System and its Hardware Configiuration 263
5 Optical Arrangement andWorking Principles 265
6 FG-CCD Sensor Installation, Spot Pattern Projection and Effective Visible Area 267
7 Operational Software Development 268
7.1 Reference Spots Frame Generation 269
7.2 Real-Time Processing 270
8 Application and Experimental Results 272
9 Conclusion 275
References 276
Dynamic VRML-Based Navigable 3D Map for Indoor Location- Aware Systems 278
1 Introduction 278
2 Indoor Location-Aware Systems 279
2.1 Cricket-Based Location-Aware System 279
2.2 RSSI-Based Location-Aware System 280
3 Modeling Approach Using VRML 281
3.1 Acquiring Data 282
3.2 Constructing 3D Map 283
3.3 Finalizing and Visualizing 3D Map 283
4 Visibility Computations and Determination 285
4.1 Portal Culling Algorithm 285
5 3D Navigation Viewer (3DNV) 287
5.1 System Architecture of 3DNV 287
6 System Implementation and Evaluation 290
7 Conclusion 293
References 293
Ultrasonic Sensor 294
Ultrasonic Sensing: Fundamentals and its Applications to Nondestructive Evaluation 295
1 Introduction 295
2 Fundamentals of Ultrasound 296
2.1 Ultrasonic Waves in Media 296
2.2 Features of Ultrasonic Waves 297
3 Measurement of Ultrasound 302
3.1 Generation and Detection of Ultrasonic Waves 302
3.2 Basics of Instrumentation 306
4 Applications to Nondestructive Evaluation 308
4.1 Buffer Rod Sensors for High Temperature Monitoring 308
4.2 Imaging Using Focused Sensors 309
4.3 In-Situ Monitoring of Solid-Liquid Interface 310
4.4 Monitoring of Internal Temperature Distribution 310
5 Conclusion 312
References 312
Image Sensor 314
Multimodal Image Sensor Fusion Using Independent Component Analysis 315
1 Introduction 315
2 Image Analysis Using ICA 317
3 Overview of Fusion Metrics 318
3.1 Piella Metric 318
3.2 Petrovic Metric 319
4 Proposed Fusion Method Using Independent Component Analysis 320
4.1 Separated Training Sets 320
4.2 Region-Based Fusion of ICA Coefficients 321
4.3 Reconstruction of the Fused Image Using Fusion Metrics 323
5 Experimental Results 323
5.1 Comparison with the Standard ICA Image Fusion Method 324
5.2 Comparison with the State-of-the-Art Image Fusion Methods 324
6 Conclusion 331
References 331
Vision Sensing 332
Fast Image Capture and Vision Processing For Robotic Applications 333
1 Introduction 333
2 Global Vision - Sources of Error 335
2.1 Separate Processing of Odd and Even Scan Fields of an Interlaced Bit Mapped Image 335
2.2 Variation of Light Intensity 336
2.3 Inherent Sensor Noise 337
3 Experimental Hardware Setup 337
4 Colour Segmentation, Area Thresholding, Blob Merging 338
5 Interrupt Based Multi-Buffered Image Capture 341
6 Full Tracking vs. Incremental Tracking 342
6.1 Adaptive Tracking Window Size 344
7 A Fast Access Color Look-Up-Table (LUT) 344
7.1 Limitations of Using RGB Color Space 344
7.2 Defining YUV Thresholds 345
7.3 Membership Testing 346
7.4 A One-Dimensional Color Look-Up-Table 346
7.5 Posting the Look-Up-Table 347
7.6 Inspecting the Look-Up-Table 347
8 Discrete YUV Look-Up-Table 348
8.1 Populating the Discrete YUV Look-Up-Table 349
8.2 Testing Color Class Membership 351
8.3 Color Space Transformation 351
8.4 A New Color Space 352
8.5 Experimental Results and Discussion 352
References 356
Sensors Based on Human Parameter 357
Affection Based Multi-robot TeamWork 358
1 Introduction 359
2 Taxonomy of MRT 360
3 Emotion and Emotional Intelligence 362
4 Emotional States 364
5 Emotional Roles in MAS/MRT 365
6 Development of Affection Based MRT 366
7 Affective Computing, Sensing, Expressing and Synthesis 374
8 Conclusion 376
References 376
Displacement Sensor 379
Displacement Sensor Using Magnetostrictive Wire and Decrease of its Hysteresis Error 380
1 Introduction 380
2 Operation Principle of Magnetostrictive Wire Type Displacement Sensor 381
3 Measurement of the Displacement Error 382
3.1 Measuring Method 382
3.2 Measurement Result 383
4 Consideration on the Reduction of Displacement Error 384
5 Conclusions 385
References 385
THZ Sensor 386
Submillimeter-Wave Coherent and Incoherent Sensors for Space Applications 387
1 Introduction 387
2 Applications 390
2.1 Astronomy and Astrophysics 390
2.2 Planetary Sciences 392
2.3 Earth Sciences 394
2.4 Other Applications 397
3 Submillimeter-Wave Sensors 398
3.1 Sensitivity of Coherent (Heterodyne) and Incoherent ( Direct) Detection 400
3.2 Coherent (Heterodyne) Sensors 403
3.3 Incoherent (Direct) Detectors 405
4 Future Trends 408
5 Conclusion 409
References 410
Index 415