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Transcript of 14a AP09 Piezo Lecture SOHN
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Piezoelectric Sensor and its Applications
Hoon Sohn
Department of Civil and Environmental Engineering
Daejeon, Korea
epar men o v an nv ronmen a ng neer ng
Carnegie Mellon University
Pittsburgh, PA
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Outline
•Introduction to Piezoelectricity
•
• Polarization Process
•Various types of piezo actuation and sensing modes
•Applications
•Precision control
•Power harvesting
•Guided wave based damage detection
•Impedance based damage detection
•PZT self-diagnosis
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•Non-contact and wireless excitation and sensing of PZT
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What is Piezoelectricity?
Piezoelectricity means “pressure electricity”, which is usedto describe the coupling between a material’s mechanicalan e ec r ca e av ors.
–stretched, electric charge is generated across the material.
– Inverse piezoelectric effect : Conversely, when subjected to ae ec r c vo age npu , a p ezoe ec r c ma er a mec an ca ydeforms.
silicon
δ, deformation
atoms
oxygenatoms
F Applied Force
+ +x
-
--
-
-
+
++
FixedMicroscopic View
--
- - --
+ + ++
x
-
--
-
-
+
+
+
+
+
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Piezoelectricity
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Brief History of Piezoelectricity
Pierre Curie and his brother Jacques first discovered thepiezoelectricity phenomenon in quartz and Rochelle salt in 1880 and
“ ”, .
– Piezoelectric effect was first found in certain crystalline minerals:zinc blende tourmaline uartz rochelle salt can su ar etc.
– In 1940, piezoelectricity was demonstrated in the first syntheticpiezoelectric substance – Barium titanate.
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Pierre Curie, 1905 Jacques Curie, 1926
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Natural Piezoelectric Materials
Piezoelectric Crystals (natural material)– 2 – Rochelle salt (NaKC4H4O6· H2O): water soluble
– EDT (ethylene diamine tartrate) and DKT (diapotassium tartrate) –
– Perovskite family: the group of ferroelectric crystals represented byBaTiO3 is called the perovskite family.
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Rochelle salt
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Artificially Synthesize Piezoelectric Materials
Piezoelectric Ceramics (man-made materials) – 3
– Lead Zirconate Titanate (PbZrTiO3) = PZT, most widely used
– The composition, shape, and dimensions of a piezoelectric ceramice ement can e ta ore to meet t e requ rements o a spec cpurpose.
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Photo courtesy of MSI, MA
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Piezoelectricity (Piezo means “squeeze” in Greek)
In piezoelectric materials such as quartz, the generatedcharge (Q) is proportional to the applied force (F ):
dF Q =
dF C QV == /
Artificially polarized materials such as ceramics and some
effect.
below the Curie
+
have randomly oriented
dipoles
empera ure, s
polarization remainspermanent
-
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High temperature produces stronger agitation of dipoles and when they
are subjected to electric field, they are aligned along the field lines
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Poling (or Polarization) Process
The piezoelectric property of ceramics does not arise simply from itschemical composition.
n a on o av ng e proper ormu a on, p ezoe ec r c ceram csmust be subjected to a high electric field for a short period of time to
force the randomly oriented micro-dipoles into alignment. This" ".
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Picture courtesy of G Cook, EDO Electro Ceramics Products, and Sensor Magazine
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Poling (or Polarization) Process II
e oma ns are a gne y expos ng e e emen o a s rong,electric field, usually at an elevated temperature to accelerate the
process. roug t s po ar z ng po ng treatment, oma ns most near y
aligned with the electric field expand at the expense of domains thatare not aligned with the field.
When the electric field is removed most of the dipoles are lockedinto a configuration of near alignment. The ceramics now has apermanent polarization.
Depoling might occur if high electrical field or heat is applied to thepiezoelectric ceramics material by accident.
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How Piezoelectricity is related to Curie Temperature?
Above the Curie temperature, each perovskite crystallite
exhibits simple cubic symmetry, with no dipoles moment
Below the Curie tem erature, however, each cr stallite
has tetragonal or rhombohedral symmetry and a built-in
di ole moment which ma be reversed or switched to
certain allowed directions under an applied electric field.
certain temperature, called a Curie temperature, it will
.
temperature, the piezoelectric material will NOT regain its
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.
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Characteristics of Piezoelectric Ceramics
Mechanical Limitations– Mechanical stress sufficient to disturb the orientation of the
domains in a piezoelectric material can destroy the alignment of thedi oles. Dro in a iezoelectric element could kill the material!
Thermal Limitations– If a piezoelectric ceramic material is heated to its Curie point, the
domains will become disordered and the material will bedepolarized. The recommended upper operating temperature for a
ceramic usuall is a roximatel half-wa between 0°C and theCurie point.
– Also, sudden temperature fluctuations can generate relatively high
, .
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Characteristics of Piezoelectric Ceramics
Electronic Limitations– Exposure to a strong electric field, of polarity opposite that of the
polarizing field, will depolarize a piezoelectric material.–
cycle in which polarity is opposite that of the polarizing field.– Often the operational voltage of the piezoelectric materials are
prov e n e spec ca on
Long-Term Stability – os proper es o a p ezoe ec r c ceram c e emen egra e
gradually, in a logarithmic relationship with time after polarization.
– Exact rates of aging depend on the composition of the ceramicelement and the manufacturing process.
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Piezoelectric Properties
Because a piezoelectric ceramic is anisotropic, physical constantsrelate to both the direction of the applied mechanical or electric force
. ,each constant generally has two subscripts that indicate the
directions of the two related quantities.
the Z-axis of a rectangular system of X, Y, and Z axes. Direction X,Y, or Z is represented by the subscript 1, 2, or 3, respectively, and
, ,
or 6, respectively.
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Piezoelectricity Terminologies
Strain constant d: relates the mechanical strain producedby an applied electric field. The units may then beexpresse as me ers per me er, per vo s per me er(meters per volt).
d (m/V) = strain development / applied electric field
Volatge constant, g: relates the electric field produced by amec an ca s ress. e un may en e expresse asvolts/meter per newtons/square meter.
g (Vm/N) = open circuit electric field / applied mechanical stress
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Piezoelectricity Terminologies (continued)
Coupling constant: describe the conversion of energy bythe ceramic element from electrical to mechanical form orv ce versa. e ra o o e s ore conver e energy o onekind (mechanical or electrical) to the input energy of thesecond kind electrical or mechanical is defined as thesquare of the coupling coefficient.
k2 = mechanical energy stored / electrical energy applied or
electrical energy stored / mechanical energy applied
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Application Overview for Piezoelectric Materials
The piezoelectric effect is used in sensing applications, such as inforce or displacement sensors.
e nverse p ezoe ec r c e ec s use n ac ua on app ca ons, sucas in motors and devices that precisely control positioning, and in
generating sonic and ultrasonic signals. Piezoelectric materials are also pyroelectric. They produce electric
charge as they undergo a temperature change. So they can be usedfor thermometer (see the picture on the right).
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ezo o or c ua or ezo enera or ensor
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Various Types of Pizeo Actuators (Motors)
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Various Types of Pizeo Sensors (Generators)
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Thermal Dependency of Piezpelectric Properties
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Typical Spec Sheet of Piezoelectric Materials
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Applications: Micro Fiber Composites (MFC)
The Macro Fiber Composite (MFC) is an innovative actuator that offers- .
consists of rectangular piezo ceramic rods sandwiched between layersof adhesive and electroded polyimide film. This film containsinterdi itated electrodes that transfer the a lied volta e directl to andfrom the ribbon shaped rods. This assembly enables in-plane poling,actuation, and sensing in a sealed, durable, ready-to-use package.When embedded in a surface or attached to flexible structures, theMFC actuator provides distributed solid-state deflection and vibrationcontrol.
Inactive Zone
Interdigitized
ElectrodesPiezoceramic
Fiber
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Transition Zone with Field
Concentration
Interdigitized
Electrodes
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Applications: Piezoelectric Composites
Piezoelectric Composites– A combination of piezoelectric ceramics and polymers
to attain properties which can be not be achieved in asingle phase
Image courtesy of MSI, MA
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Applications: Precision Control Applications
Precision Machining
Nano positioning for microscope
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Photo courtesy of PI, Inc, Germany, and APC Int. Ltd., USA Positioning for laser vibrometer
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Applications: Digital Micromirror Display (TexasInstrument)
Creates the computer projector Torsional mirrors respond to charges in integrated SRAM
800,000 t ny, -sta e m rrors
Each mirror is 16 x 16 μm
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Applications: Vibration Control
Inflatable structures are beingdesigned for space exploration
,excessive vibration is one of themain concerns for this type ofstructure. Research is beinconducted to use MFC forvibration control.
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Applications: Ultrasonic Piezoelectric Motor
Advantages (compared to electromagnetic motor):faster response times, higher positioningprecision, hard brake with no backlash, highpower-to- weight ratio, and smaller packaging
envelope, lower profile (no iron cores required),an m n ma no se
Drawbacks (compared to electromagnetic motor):low horsepower.
An piezoelectric motor from EDO is shown on theright: This low-profile (<0.20 in. high), low inertiamotor uses solid-state piezoelectric crystals foraccurate, repeatable motion. The 130 kHz drivefrequency provides speeds of 250 mm/s, with a 6
ms response time and a dynamic resolution of< . m cron over severa nc es. e orce ou puto weight ratio is 14:1.
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Courtesy of G. Cook, EDO Electro-Ceramics Product
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Applications: Water Strider Robot
To develop a microrobot that takes advantage of the surface tension ofwater to stay and maneuver on water with power efficiency and agility.
characteristics of floating on the surface of water. Micro-actuators(PZT) are used to simulate water striders’ moveents.
. . .
A leading team member: Yun Seong Song 2nd year Masters student inMechanical Engineering B.S. in Mechanical Engineering and
.
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Applications: PZT based Power Harvesting
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Commercial Energy Harvesting Devices
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Another new energy harvester form Joule Thief from Adaptivenergy.com
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Applications: Electrical Impedance Method
This method utilizes electrical impedance measurements (=complex ratio of voltage and current) to infer the behavior ofstructural impedance (= ratio of force and velocity) which issensitive to local structural damage.
“monitoring for spot-welded structural joints,” by V. Giurgiutiu etal, J. Intelligent Mat. Systems and Structures, vol. 10, 1999, pp.802-812.
S
Apply forceT
R
U
C
P
ZElectr ical ImpedanceMechanical Impedance
( ..
Current Output (I)Induce strain
T
U
R
E
T(
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A li ti f th I d M th d t
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Applictions of the Impedance Method toBolt Loosening Detection
444
Baseline
40
41
42
p a
r t ( V / I )
amage
125 130 13536
37
38
39
R e a l
PZT atchFre uenc kHzFrequency (kHz)
18.6
18.83
BaselineDama e I11
12PZT 2
BaselineDamage I
18
18.2
18.4
a l p
a r t ( V / I )
9
10
a l p a r t ( V / I )
125 130 13517.4
17.6
17.8 R e
125 130 1356
7
R e
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Applications: Smart Layer
mar ayer s a n e ec r c m w u - n p ezoe ec r c sensornetworks for monitoring of the integrity of composite and metal
structures developed by Prof. F.K. Chang and commercialized by the, .comprised of distributed piezoelectric actuators and sensors.
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Image courtesy of FK Chang, Stanford Univ.
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Applications: Guided wave based damage detection
Read paper:– “Embedded NDE with Piezoelectric Wafer-Active
ensors n erospace pp cat ons, y .Giurgiutiu, Journal of Materials (JOM), Onlinespecial issue on Nondestructive Evaluation,Januar 2003.
Embedded piezoelectric wafer-active sensors(PWAS) is capable of performing in-situnondestructive evaluation NDE of structuralcomponents such as crack detection.
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Image courtesy of V. Giurgiutiu, USC
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S t i d A ti t i M d f L b W
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Symmetric and Anti-symmetric Modes of Lamb Waves
PZT wafer
Symmetric t h
i c k n e s s
Mode P l a t
Wave propagationPZT wafer
Anti-symmetric k
n e s s
o e
P l a t e t h i
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Source: http://www.me.sc.edu/research/lamss/research/Waves/ewaves.htm
Symmetric Mode of Lamb Waves
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Symmetric Mode of Lamb Waves
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Anti-Symmetric Mode of Lamb Waves
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Anti-Symmetric Mode of Lamb Waves
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Dispersion and Multi-Mode Characteristics of Lamb Waves
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Dispersion and Multi Mode Characteristics of Lamb Waves
Dispersion Curve of Group Velocity
oS 1SoS
/ m
s )
v e l o c i t y (
oA
oA1A
2S
G r o
u p
Frequency (MHz) for a given plate thickness (1/4 inch)
While wave speed is independent of frequency in bulk (body) waves, wave speed varies
with frequency in Lamb wave propagation. This dispersion carries important implications
for Lamb wave anal sis. The anal sis is further com licated b the coexistence of at least
42Asian Pacific Summer SchoolSmart Structure and System Laboratory
two modes at any given frequency.
Impact Test Setup to Seed Delamination Damage
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Impact Test Setup to Seed Delamination Damage
–, , . .
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Composite plate in a hanging condition A snap shot during an impact test
Visual Inspection of Damage after 37 m/v Impact
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Visual Inspection of Damage after 37 m/v Impact
Detection of internal delamination
via ultrasonic scan
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Change of Response Signal due to Damage
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Change of Response Signal due to Damage
Impact location
Damaged paths with DI > 0.3 Estimated DelaminationImpact location with 37 m/s
A mode
Response time signals
corresponding to a damaged path t r a i n
(from PZT 6 to PZT 9)
Before impact
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Time
Operational and Environmental Variations
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Operational and Environmental Variations
changing boundary conditions, temperature variation,
surface debris can cause false ositive indication of
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damage.
Experimental Setup for Varying Temperature
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Experimental Setup for Varying Temperature
Specimen for Varying Temperature Test
Controller
Infrared
Controller
Infraredpec menpec menea er ea er
SpecimenSpecimen
47Asian Pacific Summer SchoolSmart Structure and System LaboratoryTest using an Infrared Heater Test using a Temperature Chamber
Variations of Time Signals Under Changing Temperature (2mm crack)
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0.05
0.10
-30oC 0oC 22oC 70oC
0.100mm 0.5mm 1.0mm 2.0mm
0.100mm 0.5mm 1.0mm 2.0mm
-
0.00
O
u t p u t ( V )
0.0
.
O
u t p u t ( V )
0.0
.
O
u t p u t ( V )
0 0.02 0.04 0.06-0.10
.
Time (ms)0 0.02 0.04 0.06
-0.10
- .
Time (ms)
First arrival of S0First arrival of A0 + reflected S0
0 0.02 0.04 0.06-0.10
- .
Time (ms)
First arrival of S0First arrival of A0 + reflected S0
0.10
-30oC 0oC 22oC 70oC
Signal AB
0.10
0mm 0.5mm 1.0mm 2.0mm
0.10
0mm 0.5mm 1.0mm 2.0mm
Signal AB
0.00
0.05
u t p u t ( V )
0.0
0.05
u
t p u t ( V )
0.0
0.05
u
t p u t ( V )
0 0.02 0.04 0.06-0.10
-0.05
0 0.02 0.04 0.0
-0.10
-0.05
First arrival of S0First arrival of A0 + reflected S0
0 0.02 0.04 0.0-0.10
-0.05
First arrival of S0First arrival of A0 + reflected S0
48
me ms
Signal BC
Time (ms)Time (ms)
Signal BC48Asian Pacific Summer SchoolSmart Structure and System Laboratory
Field bridge test configuration
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Field bridge test configuration
< The overview of Samseung Bridge > < Equipment setup >
< Intact girder case > < Girder with a stiffener case >
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Field test results
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Field test results
< Comparison of raw signals > < Comparison of mode conversion >
(a) Signals from an intact girder (a) Extracted MC1
mode
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gna s rom a g r er w e s ener x rac e 2 mo e
Extracting Mode Conversion Produced by a Crack
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S0 A0AB S0 A0 AB A0S0S0 S0 /A0 A0 /S0 A0
Mode conversion
A0 /S0 S0 /A0
AB-CDAB-CD
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The usage of dual PZT transducers for reference-freeNDT
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NDT
Dual PZT transducer
Signal Ab
BB
S0A0
Signal Ab
PZT A PZT b
Signal Ba
BB
0 0Signal Ba
PZT a PZT B
Difference
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(Signal Ab- Ba)
The usage of dual PZT transducers for reference-freeNDT
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NDT
Dual PZT transducer
Signal AbS0 A0Signal Ab A0 /S0 S0 /A0
B
PZT A PZT bCrack
Signal Ba
BB
S0A0
Signal BaA0 /S0S0 /A0
PZT a PZT B
Difference
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-
Test setup
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– The dimension of each PZT:• Diameter = 18 mm, Thickness = 0.5 mm
< Testing configuration for detecting a crack on an aluminum plate >
• PSI-5A4E type
– Input signal: A tone-burst signal• Driving frequency - 150 kHz
–– Data sampling rate: 20 MS/sec
– Data averaging: 20 times
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Test results
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a Si nals ab and ba a Si nals ab and ba
b Si nals ab and ba b Si nals ab and ba
c Si nals Ab and Ba c Si nals Ab and Ba
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< Without a notch > < With a 1.5 mm depth notch >
Typical PZT Defects and Experimental Setup
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The dimension of each PZT:– 20 mm by 20 mm by 0.508
– PSI-5A4E type
Input signal: A narrowband
toneburst si nal Data sampling rate: 20 MS/sec
Data averaging: 10 times
Three different PZT conditions
-5/24/53°C
56Asian Pacific Summer SchoolSmart Structure and System Laboratory
(a) Intact condition (b) Debonded (c) Cracked
Our Approach for PZT Self-DiagnosisPZT Transducer Self-Diagnosis Schemee Overview
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To develop a PZT transducer self-diagnosis method robust to environmentalvariation
Measure PZT
(Scaling facto r): rans ucer se -sens ng
PZT Transducer defect happened
Monitor the fluctuationof PZT capacitance
(Scaling facto r)
STEP II: Detection of an abnormal PZT
condition by statistical process control
p
time
. . .. . . .. . .
.
. . . .Thresholdboundary.
LWER* Index
Change
TR* / SYM*
Indices
Chan e
Increase Decrease
No
Transducer
Defect
No
STEP III: Time reversal based PZT transducer
self-diagnosisConnection
Problem
Zero
Tem . Variat ion
NoYes No Yes
* TR: time reversal index
Cracking.
(No Transducer
Defect)
Debonding
STEP IV: Decision making based on three indices
57Asian Pacific Summer SchoolSmart Structure and System Laboratory
* SYM: symmetry index
* LWER: Lamb wave energy ratio index
Time Reversal Process with a Single PZT TransducerTime Reversal Process with a Single PZT Transducer
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LWER index
reversed in time domain
TR &
SYM
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Time Reversal based PZT Self-Diagnosis IndicesPZT Transducer Self-Diagnosis Indices
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Index
PZT Condition
Temperature
VariationIntact Debonding Cracking
Scaling Factor
(PZT capacitance)
baseline increase decrease or
decrease
TR/SYM baselinesignificant
increaseno change no change
LWER baselineshift horizontally
(left)
shift horizontally(right)
shift vertically
59Asian Pacific Summer SchoolSmart Structure and System Laboratory
TR/SYM Indices for PZT Debonding Detection: Experimental ResultPZT Debonding Detection using TR/SYM indices
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under Varying Temperatures
PZT condition Intact PZT
Debonded PZT
20mm × 20mmCracked PZT
Temp..[°C] Index 20mm × 20mm
with 4mm debonded)18mm × 20mm
-5TR 0.0704 0.3321 0.0422
SYM 0.0008 0.0657 0.0021
24TR 0.0485 0.3597 0.0334
SYM 0.00003 0.0574 0.0003
53TR 0.0596 0.3564 0.0439
60Asian Pacific Summer SchoolSmart Structure and System Laboratory
SYM 0.00003 0.0459 0.0010
PZT Crack Detection using LWER index
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LWER index shifts horizontally according to PZT size variation . LWER index shifts vertically according to temperature variation .
Intact PZT
d e x
Vertical shift due to
temperature increase
W E R
i n
Horizontal shift due to PZTsize decrease
61Asian Pacific Summer SchoolSmart Structure and System Laboratory
Freq (kHz)
Inductively coupled PZT transducer
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excite pulse receive pulse
)(t vr
r
pulsev)(t vs
s R
pulsev)(t vs s R
PZT PZT
62Asian Pacific Summer SchoolSmart Structure and System Laboratory
Prototype Inductively Coupled PZT Transducer
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PC board
26 mm
ferrite
↑ trans ucer parts
← completed
63Asian Pacific Summer SchoolSmart Structure and System Laboratory
Demonstration of Contactless Power Delivery and Data Retrievalusing a Robot System
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Girder inspection robot Scanning the PZT sensor Traverse between two PZTs
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Wheels in contact with flange Raise probe Wheel approaching stiffener
Wireless/Embedded Ultrasonic Excitation/Sensing
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Wireless Power
TransmissionPhotodiode
+
Transformer
Light
Source
EOM
Modulator
Power
Ampli fier
PhotodiodeOscilloscope
Wireless Data
ransm ss on
LED
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Shifting in Wireless Sensor Network Paradigm
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A/D Converter Microprocessor A/D Converter Microprocessor
Memory
RF Transmit ter
Active Sensor
Memory
RF Transmit ter
Passive
Sensor
Wave Generator D/A Converter
BatteryBattery
Power Demand: 40-80mW Power Demand: 600mW
Make the sensor node as “ dumb” as possible
Photodiode
Transformer Act ive Sensor
Light Source Modulator
Oscilloscope Photodiode
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Optics-based Wireless Power/Data Transmission Test Setup
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1550nm light source
Laser Diode
Make an arbit rary
waveform
Modulator Collimator
Convert optical power to electrical power
Photodiode
Generateguided wave
PZT transducer
Narrow a beam of
modulated laser
Laser Diode + Modulator
Convert electrical
signal to optical power
Analyze the guided
waves
Oscilloscope Laser Diode
Transmit data using
optical light
laser
Collimator
Wireless data transmissionConvert op tical power
to electrical power
Photodiode
67Asian Pacific Summer SchoolSmart Structure and System Laboratory
Optics-based Wireless Power/Data Transmission Demo
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Data transmission
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Optics-based Wireless Power/Data Transmission Demo
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Light Receiving Node Combined with Transformer
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Rubber pad
+ - PhotodiodeTransformer
Rubber pad
Photodiode
Rubber pad
-
+-
PZT
transducer
+
*
70Asian Pacific Summer SchoolSmart Structure and System Laboratory
., ,
* Transformer(N1:N2 = 8:160)
Experimental Setup for Embedded PZTExcitation and FBG Sensing
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Optical coupler
AWG
Tunable
Laser
EOM
EDFA
FBG
Oscilloscope
PZT A PZT B
Hole PDOpt. Cir.PD
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Comparison of AWG & TL Input Signals
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0.4 e
AWG Input TL Input
0.2
d V o l t a
-0.2 r m a l i z e
-0.4 N o
0.25 0.30 0.35-0.6
Time (ms)
72Asian Pacific Summer SchoolSmart Structure and System Laboratory
Comparison of Responses at FBG Sensorobtained from AWG & TL inputs at PZT A
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0.6
0.8
e
PZT A(AWG)-PZT B PZT A(TL)-PZT B- FBG - FBG
0.2
0.4
V o l t a
-0.2
0
m a l i
z e
-0.8
-0.6
- .
N o r
0 0.1 0.2 0.3 0.4-1
Time (ms)
73Asian Pacific Summer SchoolSmart Structure and System Laboratory
Summary and Conclusion
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Piezoelectric Transducer– Basic working principles
– , - ,
– Widely used for sensing, actuation and control applications– Especially popular for guided wave and impedance based damage detection
– , , .
Future research– Lon term reliabilit issue has been addressed et.– PZT self-diagnosis become a critical issue.
– Wiring and networking remains unsolved.
74Asian Pacific Summer SchoolSmart Structure and System Laboratory
References
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Ultrasonic Waves in Solid Media (Joseph L. Rose)Wave Motion in Elastic Solid (Karl F. Graff)Sohn, H., Park, G., Wait, J.R., Limback, N.P., Farrar, C.R., “Wavelet-Based Active Sensingfor Delamination Detection in Composite Structures,” Smart Materials and Structures , Vol.13, No. 1,pp. 153-160, 2003.Bourasseau, N., Moulin, E., Delebarre, C., and Bonniau, P., “Radome Health Monitoringwith Lamb Waves: Experimental Approach,” NDT&E International , Vol. 33, pp. 393-400,
.Kessler, S.S., “Piezoelectric-based In-situ Damage Detection of Composite Materials forStructural Health Monitoring Systems,” Ph.D. Dissertation, MIT, Massachusetts, 2002.Staszewski, W.J., Pierce, S.G., Worden, K., and Culshaw, B., “Cross-Wavelet Analysis forLamb Wave Dama e Detection in Com osite Materials usin O tical Fibre ” Ke Engineering Materials , Vol. 167-168, pp. 373-380, 1999.Badcock, R.A. and Birt, E.A., “The Use of 0-3 Piezocomposite Embedded Lamb WaveSensors for Detection of Damage in Advanced Fibre Composites,” Smart Materials and Structures , Vol. 9, pp. 291-297, 2000. em s re, . an a ageas, ., ruc ura ea on or ng ys em ase on rac eLamb Wave Analysis by Multiresolution Processing,” Smart Materials and Structures, Vol.10, pp. 504-511, 2001.Okafor, A.C., Chandrashekhara, K., Jiang, Y.P., and Kilcher, R.R., “Damage Assessment
”,Proceedings of SPIE , Vol. 2191, pp. 265-275, 1994.Monnier, T., Guy, P., Jayet, Y., Baboux, J.C., and Salvia, M., “Health Monitoring of SmartComposite Structures Using Ultrasonic Guided Waves,” Proceedings of SPIE , Vol. 4073,2000.
75Asian Pacific Summer SchoolSmart Structure and System Laboratory
ce ent ec no og es, nc. < ttp: www.ace ent.com >, .
References (cont)
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Abbate, A., Koay, J., Frankel, J., Schroeder, S.C., Das, P., “Signal Detection and NoiseSuppression Using a Wavelet Transform Signal Processor: Application to Ultrasonic FlawDetection ” IEEE Transactions on Ultrasonics Ferroelectrics and Fre uenc Control Vol.44, pp. 14-26, 1997.Lamb, H., “On Waves in an Elastic Plate,” Proceedings of the Royal Society of London,Series A, Vol. 93, pp. 293-312, 1917.Gürdal, Z., Haftka, R.T., and Hajela, P., Design and Optimization of Laminated Composite
a er a s , o n ey ons, nc, ew or , , .“Vallen System: The Acoustic Emission Company.” <http://www.vallen.de/>, 2003.Tan, K.S., Guo, N., Wong, B.S., and Tui, C.G., “Experimental Evaluation of Delaminationsin Composite Plates by the Use of Lamb Waves,” Composite Science and Technology , Vol.
-, . , .Lind, R., Kyle, S., and Brenner, M., “Wavelet Analysis to Characterize Non-linearities andPredict Limit Cycles of an Aeroelastic System,” Mechanical Systems and Signal Processing , Vol. 15, pp. 337-356, 2001.Sohn, H., Allen, D.W., Worden, K. and Farrar, C.R., “Structural Damage Classificationusing Extreme Value Statistics,” su m tte for pu cat on of ourna of ynam c Systems, Measurement, and Control , 2003.Fisher, R.A. and Tippett, L.H.C., “Limiting Forms of the Frequency Distributions of theLargest or Smallest Members of a Sample,” Proceedings of the Cambridge Philosophical
-, , . , .Castillo, E., Extreme Value Theory in Engineering , Academic Press Series in StatisticalModeling and Decision Science, San Diego, CA, 1998.Wang, C.S., and Chang, F.K., “Diagnosis of Impact Damage in Composite Structures withBuilt-in Piezoelectrics Network,” Proceedings of SPIE , Vol. 3990, pp.13-19, 2000.
76Asian Pacific Summer SchoolSmart Structure and System Laboratory#13 Guided
References (cont)
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David Greve, Hoon Sohn, Patrick Yue, Irving J. Oppenheim, “An Inductively-CoupledLamb Wave Transducer,” submitted to IEEE Sensors Journal , 2006.David W. Greve, Irving J. Oppenheim, Hoon Sohn, C. Patrick Yue “An Inductively Coupled(wireless) Lamb Wave Transducer,” The 3rd International Workshop on Advanced Smart Materials and Smart Structures Technology , Lake Tahoe, CA, May 29-30, 2006Seung Dae Kim, Chi Won In, Kelly E. Cronin, Hoon Sohn, Kent Harries, “A Reference-FreeNDT Technique for Debonding Detection in CFRP Strengthened RC Structures,” submitted
, , .Sangjun Lee and Hoon Sohn, “Active Self-Sensing Scheme Development for StructuralHealth Monitoring,” submitted to Smart Materials and Structures, 2006.Sang Jun Lee, Hoon Sohn, "Active Self-sensing Module for Sensor Diagnosis andStructural Health Monitoring", Proceedings of Third European Workshop on Structural Health Monitoring , Granada, Spain, July 5-7, 2006.Piezoelectric Sensorics , by G. Gautschi, Springer-Verlag, 2002.Piezoelectricity: An Introduction to the Theory and Applications of Electromechanical Phenomena in Crystals, by W.G. Cady, Dover, New York 1964
, . , . . ., . , ,Fundamentals of Piezoelectricity, by T. Ikeda, Oxford University Press, Oxford, 1990The Principles of Piezoelectric Accelerometers, by G. Kulwanoski and J. Schnellinger,Sensors, 21(2): 27-33, 2004.Ferroelectric Sensors , by D. Damjanovic, P. Muralt, and N. Setter, IEEE Sensors Journal,
vol.1, no.3, October 2001, pp. 191-206.
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