Sensors and Actuators Introduction to sensors · Department of Electrical Engineering Electronic...
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Department of Electrical Engineering Electronic Systems Sensors and Actuators Introduction to sensors Sander Stuijk ([email protected])
Transcript of Sensors and Actuators Introduction to sensors · Department of Electrical Engineering Electronic...
Department of Electrical Engineering
Electronic Systems
Sensors and Actuators
Introduction to sensors
Sander Stuijk
2
5ES00 = 5CI30 + 5CI31 3 ECTS awarded for each CI course passed
3 Embedded systems
an embedded system is a device used to
control, monitor or assist the operation of
equipment, machinery or plant.
“embedded" reflects the fact that the information
processing system is an integral part of the
device.
4 Embedded systems
embedded systems make up a large percentage of the product cost
embedded systems are the driving force behind the
only silent revolution the world has ever seen
5 Embedded systems
embedded systems are different from
personal computers
embedded systems are
reliable
consider many demands
(energy, code size, ...)
designed for a specific application
often real-time
often reactive
6 Embedded systems
an embedded system consists of
an actuator
a sensor
an embedded processor
and often a communication network
processor
sensor
actuator
communication
7
PRACTICAL NOTES
8 Prior knowledge
you should be familiar with the following subjects
signal processing
electronics
special lectures and labs are organized for students that lack this
background ...
9 Prior knowledge – signal processing
you should be familiar with ...
sinusoidal waves
complex numbers, phasors and phasor addition rule
spectral representation of signals, harmonic frequencies and
multiplication
Fourier transform
AD/DA conversion: sampling, quantization and under-sampling
FIR filter
power and noise
lectures on this topic are ...
mandatory for BTI, BTB, BTW, BID, BST, BW
part of `digital signal processing (5HH30)’
lecture on Thursday (optional), instruction on Friday
exam question during exam of 5CI30
10 Prior knowledge – signal processing
example question
11 Prior knowledge – electronics
you should be familiar with ...
passive components (R, L, C)
operational amplifiers
complex impedance of a circuit
circuits needed for AD/DA conversion
circuits needed for filtering
transistors
lectures on this topic are ...
mandatory for BTI, BTB, BTW, BID, BST, BW
part of `actuation techniques (5CI31)’
12 Prior knowledge – electronics
example question
Z4
+
-
Vin
Vout
i2
i3
V-
V+
i1Z1 Z2
Z3
Va
Figuur 4
5.1 In Figuur 4 is een schakeling met een opamp getekend. Veronderstel dat de
eigenschappen van de opamp ideaal zijn.
a. Wat is de relatie tussen V+ en V- ? (0.2/2.5)
b. Stel de Kirchhoff stroomwet op voor punt Va. (0.2/2.5)
c. Bereken de spanning Va als functie van Z1 ,Z2, Z3 en Vin met behulp van de Kirchhoff
stroom wet. (0.4/2.5)
d. Bereken i2. (0.2/2.5)
e. Beschrijf Vout als functie van Z1 ,Z2, Z3, Vin en Z4 (0.4/2.5)
13 Schedule (Quartile 1)
physics (BEI, BTN, BBT)
electronics (BTI, BTB, BTW, BID, BST, BW)
students join instructions of 5HH30 (digital signal processing)
14 Schedule (Quartile 2)
physics (BEI, BTN, BBT)
electronics (BTI, BTB, BTW, BID, BST, BW)
location to be announced later
15 Exam
written exam of 3 hours
includes question on signal processing (if applicable)
no notebooks allowed
exam scheduled in Q2 (January 23th) and Q3 (April 17th)
16 Course material
book
J. Fraden, Handbook of Modern Sensors: Physics, Designs, and
Applications, ISBN 978-0-387-00750-2
available online from Springer
additional material from OASE
Introducing Electronics
Signal processing: the basics
slides, instruction exercises, old exams
www.es.ele.tue.nl/education/SensorsActuators
video lectures from 2011-2012 (no instructions)
videocollege.tue.nl
17 Course material
exercises and short questions embedded in slides
marked in bold with question mark
solutions provided on slides
instructions
exercises available on the website
solutions provided on blackboard, not available online
exams
some previous exams available on the website
no answers or solutions provided (ask in case of doubt)
one exam will be practiced in week 14
18 A few words on 5CI31…
Studenten EE, N, BMT
week 1 Sept 4/6
week 2 Sept 11/13
week 3 Sept 18/20
week 4 Sept 25/27
week 5 Oct 2/4
week 6 Oct 9/11
week 7 Oct 16/18
week 8 Oct 23/25
Woe, uur 7-8 MF 07
X Instructions X Instructions Instructions X Instructions Instructions
Vri, uur 3-4 MF 07
Actuators Actuators Actuators Displays Displays Actuators Actuators Actuators
Vri, uur 7-8 PT 6.05
X Advanced Actuators
Advanced Actuators
Advanced Actuators
Advanced Actuators
Advanced Actuators
Advanced Actuators
Advanced Actuators
Andere studenten
week 1 Sept 4/6
week 2 Sept 11/13
week 3 Sept 18/20
week 4 Sept 25/27
week 5 Oct 2/4
week 6 Oct 9/11
week 7 Oct 16/18
week 8 Oct 23/25
Woe, uur 7-8 MF 07
X Instructions X Instructions Instructions X Instructions Instructions
Vri, uur 3-4 MF 07
Actuators Actuators Actuators Displays Displays Actuators Actuators Actuators
Vri, uur 7-8 PT 6.23
Intro to Electronics
Intro to Electronics
Intro to Electronics
Intro to Electronics
Intro to Electronics
Intro to Electronics
Intro to Electronics
Intro to Electronics
Actuators, Advanced Actuators, Instructions: Aleksandar Borisavljevic Displays: Gerard de Haan Intro to Electronics: Ruud Sprangers
19 Software for 5CI31
Download and install Maxwell SV software from
http://www.ele.tue.nl/downloads/5ES00/MaxwellSV.zip
20
INTRODUCTION TO SENSORS (Chapter 1)
21 Sensors are everywhere...
22 Example – Smartphone
5Mpixel camera LED flash speaker
buttons optical trackball capacitive touch screen microphone
proximity/light sensor processing
23 Sensors and actuators
sensors and actuators are common devices
a system of any complexity cannot be designed without them
why can a system not perform its tasks without sensors?
complexity
uncertainty
dynamic world
detection / correction of errors
24 Information-processing systems
information-processing system consist of
sensors
interface electronic circuits
processing elements
actuators
interface electronics
signal processing
25 Example – Temperature control
sense the temperature of a CPU
control the speed of the fan to keep the temperature constant
A/D and signal conditioner can be separated from the processor
circuitry may be integrated into a “smart sensor”
26 Example – Level control system
information-processing system
sensor (sight tube + optic nerve)
processing (brain)
actuator (hand + valve)
this sensor converts radiant energy to electrical energy
27 Animal senses
bats
ultrasound (mechanical)
shark
electrical field
snake
thermal radiation
rats
touch (mechanical)
fish
sound vibrations
(mechanical)
birds
magnetic field
28
Signal domain
Energy domain
Signals-carrying energy
Radiant
Mass Mechanical Molecular
Thermal
Gravitational
Atomic
Nuclear
Electrostatic /
Electromagnetic
Radiant
Chemical
Mechanical Magnetic
Thermal Electrical
29 Sensors, transducers and actuators
Radiant
Chemical
Mechanical Magnetic
Thermal Electrical
a transducer converts a stimulus from a signal domain to another
signal domain
a sensor receives a stimulus and responds with an electrical signal
complex sensor direct sensor
an actuator converts an electrical signal to another signal domain
30 Example - loudspeaker system
a transducer converts a stimulus from a signal domain to another
signal domain
a sensor receives a stimulus and responds with an electrical signal
an actuator converts an electrical signal to another signal domain
mechanical signal mechanical signal electrical signal
sensor actuator
31 Electrical signal domain
why do we prefer a transducer that produces a signal in the
electrical domain?
a signal in any domain can be converted to a signal in the electrical
domain
energy does not have to be drained from the processes being
measured, instead an amplifier can be used
many electrical signal conditioners exist
many options exist to process, display and store electrical
information
it is easy to communicate electrical signals
32 Example - telephone
mechanical signal mechanical signal electrical signal
sensor actuator
microphone converts sound to change of resistance
no transduction takes place (no change of energy)
power source must be added to affect transduction
a telephone works in a different way
33 Sensor classification - excitation
an active sensor requires external power to operate
a passive (self-generating) sensor generates its own electrical signal
sensor classification
1 passive
2 passive
3 passive
4 active
5 passive
passive active
34 Sensor classification – sensor placement
a contact sensor requires physical contact with the object
a non-contact requires no physical contact with the object
an internal sensor is used within the data acquisition system itself
sensor classification
1 passive non-contact
2 passive contact
3 passive contact
4 active contact
5 passive internal
35 Sensor classification – reference point
an absolute sensor reacts to a stimulus on an absolute scale
a relative sensor senses the stimulus relative to a fixed or variable
reference
sensor classification
1 passive non-contact
2 passive contact
3 passive contact
4 active contact
5 passive internal
36 Sensor classification – physical effect
transducers (sensors) employ physical effects to convert a stimulus
from a signal domain to another signal domain
in \ out radiation mechanical thermal electrical magnetic chemical
radiation photo
luminance
radiation
pressure
radiation
heating
photo-
conduction
photo-
magnetic
photo-chemical
mechanical photo-elastic
effect
conservation
moment
friction
heat
piezo-
electric
magneto-
strict.
pressure induced
explosion
thermal incandescen
ce
thermal
expansion
heat
conduction
Seebeck
effect
Curie-Weiss
law
endothermic
reaction
electrical inject
luminance
piezo-electric Peltier
effect
pn-junction
effect
Ampere’s
law
electrolysis
magnetic Faraday
effect
Magneto-
striction
Ettinghaus
en effect
Hall effect Magnetic
induction
chemical Chemo-
luminance
Explosive
reaction
Exotherma
l reaction
Volta effect Chemical reaction
37 Sensor classification – type / quantity measured
S
e
n
s
o
r
t
y
p
e
Quantity
Position, distance,
displacement
Flow rate /
Point velocity
Force Temperature
Resistive Magnetoresistor Thermistor Strain gage RTD
Potentiometer Thermistor
Capacitive Differential capacitor Capacitive strain
gage
Inductive and
electro-
magnetic
Eddy currents LVDT Load cell + LVDT
Hall effect Magnetostriction
LVDT
Magnetostriction
Self-
generating
Thermal
transport +
thermocouple
Piezoelectric
sensor
Pyroelectric sensor
Thermocouple
PN junction Photoelectric sensor Diode
Bipolar transistor
Digital Position encoder Quartz oscillator
Optic
Ultrasound Travel time Doppler effect
there are many other interesting quantities: acceleration, vibration,
humidity, level, pressure, velocity, ...
