Sensors, Actuators, and Their Interfaces: A multidisciplinary introduction

Cover
Contents
Preface with publisher's acknowledgments
Challenges
Multidisciplinary approach
Organization
Limitations
Resources
Conclusion
Publisher's acknowledgments
About the author
1 Introduction
1.1 Introduction
1.2 A short historical note
1.3 Definitions
1.4 Classification of sensors and actuators
1.5 General requirements for interfacing
1.6 Units
1.6.1 Base SI units
1.6.2 Derived units
1.6.3 Supplementary units
1.6.4 Customary units
1.6.5 Prefixes
1.6.6 Other units and measures
1.6.6.1 Units of information
1.6.6.2 The decibel (dB) and its use
1.6.7 Convention for use of units
1.7 Problems
Reference
2 Performance characteristics of sensors and actuators
2.1 Introduction
2.2 Input and output characteristics
2.2.1 Transfer function
2.2.2 Impedance and impedance matching
2.2.3 Range, span, input and output full scale, resolution, and dynamic range
2.2.4 Accuracy, errors, and repeatability
2.2.5 Sensitivity and sensitivity analysis
2.2.6 Hysteresis, nonlinearity, and saturation
2.2.7 Frequency response, response time, and bandwidth
2.2.8 Calibration
2.2.9 Excitation
2.2.10 Deadband
2.2.11 Reliability
2.3 Simulation
2.4 Problems
3 Temperature sensors and thermal actuators
3.1 Introduction
3.1.1 Units of temperature, thermal conductivity, heat, and heat capacity
3.2 Thermoresistive sensors
3.2.1 Resistance temperature detectors
3.2.1.1 Self-heat of RTDs
3.2.1.2 Response time
3.2.2 Silicon resistive sensors
3.2.3 Thermistors
3.3 Thermoelectric sensors
3.3.1 Practical considerations
3.3.2 Semiconductor thermocouples
3.3.3 Thermopiles and thermoelectric generators
3.4 p-n junction temperature sensors
3.5 Other temperature sensors
3.5.1 Optical and acoustical sensors
3.5.2 Thermomechanical sensors and actuators
3.6 Problems
4 Optical sensors and actuators
4.1 Introduction
4.2 Optical units
4.3 Materials
4.4 Effects of optical radiation
4.4.1 Thermal effects
4.4.2 Quantum effects
4.4.2.1 The photoelectric effect
4.4.2.2 Quantum effects: the photoconducting effect
4.4.2.3 Spectral sensitivity
4.4.2.4 Tunneling effect
4.5 Quantum-based optical sensors
4.5.1 Photoconducting sensors
4.5.2 Photodiodes
4.5.3 Photovoltaic diodes
4.5.4 Phototransistors
4.6 Photoelectric sensors
4.6.1 The photoelectric sensor
4.6.2 Photomultipliers
4.7 Charge coupled (CCD) sensors and detectors
4.8 Thermal-based optical sensors
4.8.1 Passive IR sensors
4.8.1.1 Thermopile PIR
4.8.1.2 Pyroelectric sensors
4.8.1.3 Bolometers
4.9 Active far infrared (AFIR) sensors
4.10 Optical actuators
4.11 Problems
5 Electric and magnetic sensors and actuators
5.1 Introduction
5.2 Units
5.3 The electric field: capacitive sensors and actuators
5.3.1 Capacitive position, proximity, and displacement sensors
5.3.2 Capacitive fluid level sensors
5.3.3 Capacitive actuators
5.4 Magnetic fields: sensors and actuators
5.4.1 Inductive sensors
5.4.1.1 Inductive proximity sensors
5.4.1.2 Eddy current proximity sensors
5.4.1.3 Position and displacement sensing: variable inductance sensors
5.4.2 Hall effect sensors
5.5 Magnetohydrodynamic (MHD) sensors and actuators
5.5.1 MHD generator or sensor
5.5.2 MHD pump or actuator
5.6 Magnetoresistance and magnetoresistive sensors
5.7 Magnetostrictive sensors and actuators
5.7.1 Magnetostrictive actuators
5.8 Magnetometers
5.8.1 Coil magnetometer
5.8.2 The fluxgate magnetometer
5.8.3 The SQUID
5.9 Magnetic actuators
5.9.1 Voice coil actuators
5.9.2 Motors as actuators
5.9.2.1 Operation principles
5.9.2.2 Brushless, electronically commutated DC (BLDC) motors
5.9.2.3 AC motors
5.9.2.4 Stepper motors
5.9.2.5 Linear motors
5.9.2.6 Servomotors
5.9.3 Magnetic solenoid actuators and magnetic valves
5.10 Voltage and current sensors
5.10.1 Voltage sensing
5.10.2 Current sensing
5.10.3 Resistance sensors
5.11 Problems
6 Mechanical sensors and actuators
6.1 Introduction
6.2 Some definitions and units
6.3 Force sensors
6.3.1 Strain gauges
6.3.2 Semiconductor strain gauges
6.3.2.1 Application
6.3.2.2 Errors
6.3.3 Other strain gauges
6.3.4 Force and tactile sensors
6.4 Accelerometers
6.4.1 Capacitive accelerometers
6.4.2 Strain gauge accelerometers
6.4.3 Magnetic accelerometers
6.4.4 Other accelerometers
6.5 Pressure sensors
6.5.1 Mechanical pressure sensors
6.5.2 Piezoresistive pressure sensors
6.5.3 Capacitive pressure sensors
6.5.4 Magnetic pressure sensors
6.6 Velocity sensing
6.7 Inertial sensors: gyroscopes
6.7.1 Mechanical or rotor gyroscopes
6.7.2 Optical gyroscopes
6.8 Problems
7 Acoustic sensors and actuators
7.1 Introduction
7.2 Units and definitions
7.3 Elastic waves and their properties
7.3.1 Longitudinal waves
7.3.2 Shear waves
7.3.3 Surface waves
7.3.4 Lamb waves
7.4 Microphones
7.4.1 The carbon microphone
7.4.2 The magnetic microphone
7.4.3 The ribbon microphone
7.4.4 Capacitive microphones
7.5 The piezoelectric effect
7.5.1 Electrostriction
7.5.2 Piezoelectric sensors
7.6 Acoustic actuators
7.6.1 Loudspeakers
7.6.2 Headphones and buzzers
7.6.2.1 The magnetic buzzer
7.6.2.2 The piezoelectric headphone and piezoelectric buzzer
7.7 Ultrasonic sensors and actuators: transducers
7.7.1 Pulse-echo operation
7.7.2 Magnetostrictive transducers
7.8 Piezoelectric actuators
7.9 Piezoelectric resonators and saw devices
7.10 Problems
8 Chemical and biological sensors and actuators
8.1 Introduction—chemistry and biochemistry
8.2 Chemical units
8.3 Electrochemical sensors
8.3.1 Metal oxide sensors
8.3.2 Solid electrolyte sensors
8.3.3 The metal oxide semiconductor chemical sensor
8.4 Potentiometric sensors
8.4.1 Glass membrane sensors
8.4.2 Soluble inorganic salt membrane sensors
8.4.3 Polymer-immobilized ionophore membranes
8.4.4 Gel-immobilized enzyme membranes
8.4.5 The ion-sensitive field-effect transistor
8.5 Thermochemical sensors
8.5.1 Thermistor-based chemical sensors
8.5.2 Catalytic sensors
8.5.3 Thermal conductivity sensors
8.6 Optical chemical sensors
8.7 Mass sensors
8.7.1 Mass humidity and gas sensors
8.7.2 SAW mass sensors
8.8 Humidity and moisture sensors
8.8.1 Capacitive moisture sensors
8.8.2 Resistive humidity sensor
8.8.3 Thermal conduction moisture sensors
8.8.4 Optical humidity sensor
8.9 Chemical actuation
8.9.1 The catalytic converter
8.9.2 The airbag
8.9.3 Electroplating
8.9.4 Cathodic protection
8.10 Problems
9 Radiation sensors and actuators
9.1 Introduction
9.2 Units of radiation
9.3 Radiation sensors
9.3.1 Ionization sensors (detectors)
9.3.1.1 Ionization chambers
9.3.1.2 Proportional chamber
9.3.1.3 Geiger–Muller counters
9.3.2 Scintillation sensors
9.3.3 Semiconductor radiation detectors
9.3.3.1 Bulk semiconductor radiation sensor
9.3.3.2 Semiconducting junction radiation sensors
9.4 Microwave radiation
9.4.1 Microwave sensors
9.4.1.1 Radar
9.4.1.2 Reflection and transmission sensors
9.4.1.3 Resonant microwave sensors
9.4.1.4 Propagation effects and sensing
9.5 Antennas as sensors and actuators
9.5.1 General relations
9.5.2 Antennas as sensing elements
9.5.2.1 Triangulation, multilateration, and the global positioning system
9.5.3 Antennas as actuators
9.6 Problems
10 MEMS and smart sensors and actuators
10.1 Introduction
10.2 Production of MEMS
10.3 MEMS sensors and actuators
10.3.1 MEMS sensors
10.3.1.1 Pressure sensors
10.3.1.2 Mass air flow sensors
10.3.1.3 Inertial sensors
10.3.1.4 Angular rate sensors
10.3.2 MEMS actuators
10.3.2.1 Thermal and piezoelectric actuation
10.3.2.2 Electrostatic actuation
10.3.3 Some applications
10.3.3.1 Optical switches
10.3.3.2 Mirrors and mirror arrays
10.3.3.3 Pumps
10.3.3.4 Valves
10.3.3.5 Other MEMS devices
10.4 Nanosensors and actuators
10.5 Smart sensors and actuators
10.5.1 Wireless sensors and actuators and issues associated with their use
10.5.1.1 The ISM and SRD bands
10.5.1.2 The wireless link and data handling
10.5.1.3 Transmitters, receivers, and transceivers
10.5.2 Modulation and demodulation
10.5.2.1 Amplitude modulation
10.5.2.2 Frequency modulation
10.5.2.3 Phase modulation
10.5.2.4 Amplitude shift keying
10.5.2.5 Frequency shift keying
10.5.2.6 Phase shift keying
10.5.3 Demodulation
10.5.3.1 Amplitude demodulation
10.5.3.2 Frequency and phase demodulation
10.5.4 Encoding and decoding
10.5.4.1 Unipolar and bipolar encoding
10.5.4.2 Biphase encoding
10.5.4.3 Manchester code
10.6 RFIDs and embedded sensors
10.7 Sensor networks
10.8 Problems
11 Interfacing methods and circuits
11.1 Introduction
11.2 Amplifiers
11.2.1 The operational amplifier
11.2.1.1 Differential voltage gain
11.2.1.2 Common-mode voltage gain
11.2.1.3 Bandwidth
11.2.1.4 Slew rate
11.2.1.5 Input impedance
11.2.1.6 Output impedance
11.2.1.7 Temperature drift and noise
11.2.1.8 Power requirements
11.2.2 Inverting and noninverting amplifiers
11.2.2.1 The inverting amplifier
11.2.2.2 The noninverting amplifier
11.2.3 The voltage follower
11.2.4 The instrumentation amplifier
11.2.5 The charge amplifier
11.2.6 The integrator and the differentiator
11.2.7 The current amplifier
11.2.8 The comparator
11.3 Power amplifiers
11.3.1 Linear power amplifiers
11.3.2 PWM and PWM amplifiers
11.4 Digital circuits
11.5 A/D and D/A converters
11.5.1 A/D conversion
11.5.1.1 Threshold digitization
11.5.1.2 Threshold voltage-to-frequency conversion
11.5.1.3 True A/D converters
11.5.1.4 Dual-slope A/D converter
11.5.1.5 Successive approximation A/D
11.5.1.6 Flash analog-to-digital converter
11.5.2 D/A conversion
11.5.2.1 Resistive ladder network D/A conversion
11.5.2.2 PWM D/A conversion
11.5.2.3 Frequency-to-voltage (F/V) D/A conversion
11.6 Bridge circuits
11.6.1 Sensitivity
11.6.2 Bridge output
11.7 Data transmission
11.7.1 Four-wire transmission
11.7.2 Two-wire transmission for passive sensors
11.7.3 Two-wire transmission for active sensors
11.7.4 Digital data transmission protocols and buses
11.8 Excitation methods and circuits
11.8.1 Linear power supplies
11.8.2 Switching power supplies
11.8.3 Current sources
11.8.4 Voltage references
11.8.5 Oscillators
11.8.5.1 Crystal oscillators
11.8.5.2 LC and RC oscillators
11.9 Power harvesting
11.9.1 Solar power harvesting
11.9.2 Thermal gradient power harvesting
11.9.3 Magnetic induction and RF power harvesting
11.9.4 Power harvesting from vibrations
11.10 Noise and interference
11.10.1 Inherent noise
11.10.2 Interference
11.11 Problems
12 Interfacing to microprocessors
12.1 Introduction
12.2 The microprocessor as a general-purpose controller
12.2.1 Architecture
12.2.2 Addressing
12.2.3 Execution and speed
12.2.4 Instruction set and programming
12.2.5 Input and output
12.2.6 Clock and timers
12.2.7 Registers
12.2.8 Memory
12.2.9 Power
12.2.10 Other peripherals and functionalities
12.2.11 Programs and programmability
12.3 General requirements for interfacing sensors and actuators
12.3.1 Signal level
12.3.2 Impedance
12.3.3 Frequency and frequency response
12.3.4 Input signal conditioning
12.3.4.1 Offset
12.3.4.2 Scaling
12.3.4.3 Isolation
12.3.4.4 Loading
12.3.5 Output signals
12.4 Errors
12.4.1 Resolution errors
12.4.2 Computation errors
12.4.3 Sampling and quantization errors
12.4.4 Conversion errors
12.5 Problems
Appendix A. Least squares polynomials and data fitting
A.1 Linear least square data fitting
A.2 Parabolic least squares fit
Appendix B. Thermoelectric reference tables
B.1 Type J thermocouples (iron/constantan)
B.2 Type K thermocouples (chromel/alumel)
B.3 Type T thermocouples (copper/constantan)
B.4 Type E thermocouples (chromel/constantan)
B.5 Type N thermocouples (nickel/chromium–silicon)
B.6 Type B thermocouples (platinum [30%]/rhodium–platinum)
B.7 Type R thermocouples (platinum [13%]/rhodium–platinum)
B.8 Type S thermocouples (platinum [10%]/rhodium–platinum)
Appendix C. Computation on microprocessors
C.1 Representation of numbers on microprocessors
C.1.1 Binary numbers: unsigned integers
C.1.2 Signed integers
C.1.3 Hexadecimal numbers
C.2 Integer arithmetic
C.2.1 Addition and subtraction of binary integers
C.2.2 Multiplication and division
C.2.2.1 Binary integer multiplication
C.2.2.2 Binary integer division
C.3 Fixed point arithmetic
Answers to problems
Index
Back Cover