Evaluation of piezoelectric smart materials …jamme.acmsse.h2.pl/papers_vol55_2/58221.pdffixed to its ribs and spontaneous breathing led to a peak voltage of 18 V, which corresponded

© Copyright by International OCSCO World Press. All rights reserved. 2012 Research paper 355

VOLUME 55

ISSUE 2

December

2012of Achievements in Materialsand Manufacturing Engineeringof Achievements in Materialsand Manufacturing Engineering

Evaluation of piezoelectric smart materials subjected to impact test over range of temperatures

I. Patel a,b,*, E. Siores b a British University in Egypt, Cairo, Suez Desert Road, El Sherouk City, Postal No. 11837, P.O. Box 43, Egypt b Institute for Materials Research and Innovation, The University of Bolton, Deane Road, Bolton, BL3 5AB, England, United Kingdom* Corresponding e-mail address: [email protected]

Received 18.10.2012; published in revised form 01.12.2012

Properties

AbstrAct

As the demand for technological advances increase on daily basis, so does the dependency on existing fossil fuels, which is depleting at an alarming rate. The work presented in this paper addresses key solutions to energy management, and particularly energy harvesting for powering electronic devices and sectors in general, particularly applications where components are exposed to severe subzero temperatures. This research compares the energy output in terms of voltage for 3 piezoelectric smart materials, ceramic based PZT (Lead, Zirconate Titanate), polymer membrane PVDF (Polyvinylidine Fluoride) and foam based PP (Polypropylene). Impact analysis using concentrated mass of 1.02kg from a fixed height of 17mm was allowed to drop roughly in the centre of piezoelectric material samples as the temperature was increased from approximately -33°C to room temperature. Voltage output was recorded at various temperature increments using pico-scope software, which indicated that generally, voltage increased for all 3 materials as temperature decreased. Keywords: Piezoelectric; Subzero; Temperature; Energy harvesting

Reference to this paper should be given in the following way: I. Patel, E. Siores, Evaluation of piezoelectric smart materials subjected to impact test over range of temperatures, Journal of Achievements in Materials and Manufacturing Engineering 55/2 (2012) 355-362.

1. Introduction

Piezoelectric effect is the ability of certain material to generate voltage when pressure is applied and vice versa. However, piezoelectric phenomenon should not be confused with pyroelectricity, which is the ability of certain materials to generate voltage when heated or cooled. The change in temperature alters the positions of the atoms within the crystal structure, and as such the polarization of the material changes. This polarization change gives rise to a voltage across the crystal.

Strides have been made to incorporate computers and digital systems into our everyday lives and extensive work has been carried out to investigate the possibility, practicality and efficiency of imbedding them into our clothing, or in biological systems, such as the human body [1]. The use of power harvesting devices to capture the energy lost during everyday human functions seems exciting, and as a result, it has been one of the many topics facilitating the rapid growth of the energy harvesting sector. Possibly the first investigation of power scavenging systems incorporated into a biological system was performed in 1984 by Hausler et al. [2]. Their work proposed the use of an

1. Introduction

http://www.journalamme.org


Research paper356

Journal of Achievements in Materials and Manufacturing Engineering

I. Patel,E. Siores

Volume 55 Issue 2 December 2012

implantable physiological piezoelectric PVDF film power supply. Based on the concept that the energy expended for respiration could be converted into electric power, Hausler et al used the motion of the ribs during inhalation and exhalation to deform a converter. A miniaturized prototype was designed and experiments were conducted on a dog, where a converter was fixed to its ribs and spontaneous breathing led to a peak voltage of 18 V, which corresponded to a power of about 17 µW. However, the energy generated was insufficient to power the required micro electronic device. It was assumed that optimization of the PVDF film properties, as well as more suitable converter attachment at the ribs would make it possible to produce power in the region of 1 mW, yielding a mechanical power load of 20 mW.

Throughout our daily activity, a significant amount of energy is wasted in various forms, some of which could make for attractive energy harvesting applications. A paper published by Starner in 1996 [3], carried out an investigation into the amount of power delivered from range of human activities. The paper contained a survey of several power generation methods ranging from body heat and breath to finger and upper limb motion. An analysis of the power available from each of the different locations was presented. He calculated that approximately 67 W of power is lost during walking and that a piezoelectric smart material device mounted inside a shoe with a conversion efficiency of 12.5% could achieve 8.4 W of power. One idea he explained was to place piezoelectric film patches in the joints of clothing to harvest the energy lost during movement which he estimated to be about 0.33 W.

The work of Starner [3] brought the possibility of power harvesting locations around the human body to the attention of many researchers and the work in wearable power supplies began to grow. As a result Swallow and Patel investigated the feasibility of in cooperating piezoelectric material for energy reclamation in hand glove structure [4] with accepted patent for ‘Detection and Suppression of Muscle Tremors’ Patent GB0623905.7. Recent work of Patel and Siores compared the voltage output for ceramic based PZT, polymer membrane PVDF and polymer foam PP when subjected to vibratio frequency of between 0-120 Hz and impact test under room and elevated temperatures ranging from room to approximately 150°C [5]. Post and Orth [6] investigated the concept of “smart fabric” for wearable clothing. Their research described techniques used in building circuits from commercially obtainable fabrics, fasteners etc. Multiple different conductive fabrics were explored, including silk organza, constructed of silk thread wrapped in thin copper foil that is highly conductive and can be sewn using industrial machines. Several devices have been constructed of fabric including a type of fabric keyboard that could be crumpled up, thrown in the wash and even used as a potholder without losing its ability to function. These materials would be very effective for transmitting the energy generated around the body to the storage medium in a seamless way. The use of piezoelectric actuators located inside the sole of a shoe for power harvesting was studied by Kymissis et al [7]. The piezoelectric based power harvesting devices were a multiple layered PVDF patch and a piezoelectric ceramic Thunder actuator. The PVDF patch was placed in the sole of the shoe to harvest the bending energy and the Thunder actuator was located in the heel to harvest the impact energy. It was found that the PVDF patch and Thunder actuator produced an average power of

approximately 1.1 mW and 1.8 mW of power respectively. The circuit used a capacitor to store the charge until a sufficient amount was captured. Then the circuitry allowed the power to be released to a transmitter that would send a 12-bit code. The system could transmit the code about 6-7 times every 3-6 steps.

Similar to the work of Kymissis et al. [5], Shenck’s Master’s thesis [8], demonstrated electrical energy generation from piezoelectric patches in a shoe. A rigid bimorph piezoelectric ceramic transducer was developed and integrated into a mass produced shoe insert. A design study was conducted by Ramsey and Clark [9], published in 2001, which investigated the feasibility of using a piezoelectric transducer as a power supply for a MEMS application.

Rather than developing a method of accumulating the energy developed by piezoelectric materials, Ottman et al [10] researched to develop a circuit that would maximize the power flow from the piezoelectric device. Hofmann et al. [11] extended the work of Ottman et al. [9] by implementing a similar circuit to maximize the power flow. Following the work of Sodano et al. [8], a second paper was published [12] to further investigate the ability of piezoelectric materials to recharge batteries. This study compared the macro-fiber composite (MFC) actuator with the monolithic piezoceramic material PZT for recharging batteries. The MFC is an actuator that uses piezoelectric fibers and interdigitated electrodes to capitalize on the higher g33 piezoelectric coupling coefficient, allowing it to reduce higher strain and force than typical monolithic PZT [13].

2. Materials investigated

There are three most common types of piezoelectric materials - ceramic based PZT, polymer based PVDF and polymer based foam PP. The polymer materials are soft and flexible; however, they possess lower dielectric and piezoelectric properties than ceramics. Conventional piezoelectric ceramic materials are rigid, heavy and can only be produced in block form.

The ceramic PZT which consisted of two ceramic materials, with active piezoelectric fibres of 250 µm and 120 µm diameters were embedded in a polymer matrix and encapsulated in copper-clad laminate, see Figure 1c. A ceramic Bimorph material consisting of two 250 µm fibre diameter materials adhered to either side of a rigid metal centre shim material and 4 layers of 250 µm material adhered together using standard epoxy resin. All the PZT specimens were obtained from Advanced Cerametrics Incorporated (ACI).

A laminated piezoelectric polymer material, PVDF, where two 125 µm polyester laminates were attached to the either side of a 28 µm thick piezoelectric film element and two un-laminated PVDF materials of 28 and 52 µm thickness was used, see Figure 1a. The PVDF specimens were supplied by Measurement Specialities Incorporated (MSI). Finally, a fully shielded, low mass, thin ribbon PP sample was used. The sample consisted of a sensing element constructed of elastic electret, 3 layers of polyester film. Aluminium electrodes with crimped connectors were used for connecting to electrodes and double-sided sticky tape for convenience, see Figure 1b as supplied by Emfit. The dimensions and classification of the piezoelectric polymer and ceramic materials are given in Table 1.

TableTeste

Fig. c) pieelectr

3.

P20 msampmetaFigurIn orspecia ma

e 1. ed piezoelectric

M

LDT1-28 µmLDT4-28 µm

DT4-28 µm uDT4-52 µm u

65 µm Ø12Ø25

Ø250 µm

1. Schematic repezoelectric PZTrodes. (Refer to

Experimeand discu

Pellets of dry imm in length wples. The dry iallic box size re 2a and b whicrder to minimiimen, the piezoe

asking tape onto

PVDF, PP and P

Material

m laminated PVDm laminated PVDun-laminated PVun-laminated PVlaminated PP

20 µm PZT 50 µm PZT m Bimorph PZT

presentation of p fibre embeddedTable 1 relevan

ent methussion

ice of approximwere used to re

ce pellets were(L110 mm x

ch displays the eze lateral move

electric material the top surface

PZT samples and

DF DF

VDF VDF

piezoelectric samd in an epoxy wnt dimensions)

hodology,

mately 10 mm duce the tempe

e sealed in a sW60 mm x D

experimental rigement and deflwas adequately of the metallic

d their characterWidth (mm)

16 22 22 22 20 15 15 15

mples a) PVDF ith copper clad

results

diameter and erature of the mall standard

D30 mm), see g construction. lection of the secured using box. Potential

ristics

membrane filmelectrodes etche

voltage outunder normlatch and stfilled with piezoelectriincrement wfixed heighfor any givehand held ito ascertaievaluating normal roocommencin

Length (mm)

41 171 171 171 100 140 140 140

, b) porous PP wed on to the inne

tput across opemal room temperatruck the samplepellets of dry icic material witwas repeated. Thht of 17 mm thren temperature ainfra red thermoin the temperaeach of the mm temperature u

ng further tests.

with pores approer surface of the

en circuit confiature as the mase. After this, thece and sealed, thth the mass ahe mass of 1.02 ee times withinand results wereometer (model nature of the saterials, the conuntil the tempera

Thickness (µm) 205 205 40 70

320 190 320 720

ox. 20 µm diamelaminate which

guration was res was released fr

e metallic containhe cycle of strik

at various tempkg was released

n a 5second timee averaged. A cano. CHY 110) wsample surfacentainer was lefature stabilised

eter and h acts as

ecorded from the ner was king the perature d from a e frame

alibrated was used

. After ft under prior to






357

Properties


implantable physiological piezoelectric PVDF film power supply. Based on the concept that the energy expended for respiration could be converted into electric power, Hausler et al used the motion of the ribs during inhalation and exhalation to deform a converter. A miniaturized prototype was designed and experiments were conducted on a dog, where a converter was fixed to its ribs and spontaneous breathing led to a peak voltage of 18 V, which corresponded to a power of about 17 µW. However, the energy generated was insufficient to power the required micro electronic device. It was assumed that optimization of the PVDF film properties, as well as more suitable converter attachment at the ribs would make it possible to produce power in the region of 1 mW, yielding a mechanical power load of 20 mW.

Throughout our daily activity, a significant amount of energy is wasted in various forms, some of which could make for attractive energy harvesting applications. A paper published by Starner in 1996 [3], carried out an investigation into the amount of power delivered from range of human activities. The paper contained a survey of several power generation methods ranging from body heat and breath to finger and upper limb motion. An analysis of the power available from each of the different locations was presented. He calculated that approximately 67 W of power is lost during walking and that a piezoelectric smart material device mounted inside a shoe with a conversion efficiency of 12.5% could achieve 8.4 W of power. One idea he explained was to place piezoelectric film patches in the joints of clothing to harvest the energy lost during movement which he estimated to be about 0.33 W.

The work of Starner [3] brought the possibility of power harvesting locations around the human body to the attention of many researchers and the work in wearable power supplies began to grow. As a result Swallow and Patel investigated the feasibility of in cooperating piezoelectric material for energy reclamation in hand glove structure [4] with accepted patent for ‘Detection and Suppression of Muscle Tremors’ Patent GB0623905.7. Recent work of Patel and Siores compared the voltage output for ceramic based PZT, polymer membrane PVDF and polymer foam PP when subjected to vibratio frequency of between 0-120 Hz and impact test under room and elevated temperatures ranging from room to approximately 150°C [5]. Post and Orth [6] investigated the concept of “smart fabric” for wearable clothing. Their research described techniques used in building circuits from commercially obtainable fabrics, fasteners etc. Multiple different conductive fabrics were explored, including silk organza, constructed of silk thread wrapped in thin copper foil that is highly conductive and can be sewn using industrial machines. Several devices have been constructed of fabric including a type of fabric keyboard that could be crumpled up, thrown in the wash and even used as a potholder without losing its ability to function. These materials would be very effective for transmitting the energy generated around the body to the storage medium in a seamless way. The use of piezoelectric actuators located inside the sole of a shoe for power harvesting was studied by Kymissis et al [7]. The piezoelectric based power harvesting devices were a multiple layered PVDF patch and a piezoelectric ceramic Thunder actuator. The PVDF patch was placed in the sole of the shoe to harvest the bending energy and the Thunder actuator was located in the heel to harvest the impact energy. It was found that the PVDF patch and Thunder actuator produced an average power of

approximately 1.1 mW and 1.8 mW of power respectively. The circuit used a capacitor to store the charge until a sufficient amount was captured. Then the circuitry allowed the power to be released to a transmitter that would send a 12-bit code. The system could transmit the code about 6-7 times every 3-6 steps.

Similar to the work of Kymissis et al. [5], Shenck’s Master’s thesis [8], demonstrated electrical energy generation from piezoelectric patches in a shoe. A rigid bimorph piezoelectric ceramic transducer was developed and integrated into a mass produced shoe insert. A design study was conducted by Ramsey and Clark [9], published in 2001, which investigated the feasibility of using a piezoelectric transducer as a power supply for a MEMS application.

Rather than developing a method of accumulating the energy developed by piezoelectric materials, Ottman et al [10] researched to develop a circuit that would maximize the power flow from the piezoelectric device. Hofmann et al. [11] extended the work of Ottman et al. [9] by implementing a similar circuit to maximize the power flow. Following the work of Sodano et al. [8], a second paper was published [12] to further investigate the ability of piezoelectric materials to recharge batteries. This study compared the macro-fiber composite (MFC) actuator with the monolithic piezoceramic material PZT for recharging batteries. The MFC is an actuator that uses piezoelectric fibers and interdigitated electrodes to capitalize on the higher g33 piezoelectric coupling coefficient, allowing it to reduce higher strain and force than typical monolithic PZT [13].


There are three most common types of piezoelectric materials - ceramic based PZT, polymer based PVDF and polymer based foam PP. The polymer materials are soft and flexible; however, they possess lower dielectric and piezoelectric properties than ceramics. Conventional piezoelectric ceramic materials are rigid, heavy and can only be produced in block form.

The ceramic PZT which consisted of two ceramic materials, with active piezoelectric fibres of 250 µm and 120 µm diameters were embedded in a polymer matrix and encapsulated in copper-clad laminate, see Figure 1c. A ceramic Bimorph material consisting of two 250 µm fibre diameter materials adhered to either side of a rigid metal centre shim material and 4 layers of 250 µm material adhered together using standard epoxy resin. All the PZT specimens were obtained from Advanced Cerametrics Incorporated (ACI).

A laminated piezoelectric polymer material, PVDF, where two 125 µm polyester laminates were attached to the either side of a 28 µm thick piezoelectric film element and two un-laminated PVDF materials of 28 and 52 µm thickness was used, see Figure 1a. The PVDF specimens were supplied by Measurement Specialities Incorporated (MSI). Finally, a fully shielded, low mass, thin ribbon PP sample was used. The sample consisted of a sensing element constructed of elastic electret, 3 layers of polyester film. Aluminium electrodes with crimped connectors were used for connecting to electrodes and double-sided sticky tape for convenience, see Figure 1b as supplied by Emfit. The dimensions and classification of the piezoelectric polymer and ceramic materials are given in Table 1.

TableTeste

Fig. c) pieelectr

3.

P20 msampmetaFigurIn orspecia ma

e 1. ed piezoelectric

M

LDT1-28 µmLDT4-28 µm

DT4-28 µm uDT4-52 µm u

65 µm Ø12Ø25

Ø250 µm

1. Schematic repezoelectric PZTrodes. (Refer to

Experimeand discu

Pellets of dry imm in length wples. The dry iallic box size re 2a and b whicrder to minimiimen, the piezoe

asking tape onto

PVDF, PP and P

Material

m laminated PVDm laminated PVDun-laminated PVun-laminated PVlaminated PP

20 µm PZT 50 µm PZT m Bimorph PZT

presentation of p fibre embeddedTable 1 relevan

ent methussion

ice of approximwere used to re

ce pellets were(L110 mm x

ch displays the eze lateral move

electric material the top surface

PZT samples and

DF DF

VDF VDF

piezoelectric samd in an epoxy wnt dimensions)

hodology,

mately 10 mm duce the tempe

e sealed in a sW60 mm x D

experimental rigement and deflwas adequately of the metallic

d their characterWidth (mm)

16 22 22 22 20 15 15 15

mples a) PVDF ith copper clad

results

diameter and erature of the mall standard

D30 mm), see g construction. lection of the secured using box. Potential

ristics

membrane filmelectrodes etche

voltage outunder normlatch and stfilled with piezoelectriincrement wfixed heighfor any givehand held ito ascertaievaluating normal roocommencin

Length (mm)

41 171 171 171 100 140 140 140

, b) porous PP wed on to the inne

tput across opemal room temperatruck the samplepellets of dry icic material witwas repeated. Thht of 17 mm thren temperature ainfra red thermoin the temperaeach of the mm temperature u

ng further tests.

with pores approer surface of the

en circuit confiature as the mase. After this, thece and sealed, thth the mass ahe mass of 1.02 ee times withinand results wereometer (model nature of the saterials, the conuntil the tempera

Thickness (µm) 205 205 40 70

320 190 320 720

ox. 20 µm diamelaminate which

guration was res was released fr

e metallic containhe cycle of strik

at various tempkg was released

n a 5second timee averaged. A cano. CHY 110) wsample surfacentainer was lefature stabilised

eter and h acts as

ecorded from the ner was king the perature d from a e frame

alibrated was used

. After ft under prior to

3. Experiment methodology, results and discussion





Research paper358


I. Patel,E. Siores


Fig. metaexper

3

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359

Properties


Fig. metaexper

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Fig. lamintempcaptu

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droppthat normhave tempincremate

2. Photograph leal box which riment set-up us

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eased as the temm sample, the vo

C point an increaperature, respectiv


peratures. Abovured by the pico

The Figure 4 shped to 20.47 V beyond this poi

malise and wouldbeen futile to

perature (Tg) becease in voltage rerial compared to

eft, shows placecontains dry ic

sing free standing

present averagedls, namely un-laAfter the initial e

er to reduce the te carefully remoults indicated th

mperature was reoltage output marsed to 22.61 andvely.

of voltage outpuwhen subjected


hows that beyonand at -32°C it int, the temperad not reduce anyprogress belowcomes apparent resonance was o PP sample.

ement of samplece and right, g Instron machin

d voltage output aminated with 52experiment usingtemperature of thoved from the mhat generally, voeduced. For thisrginally droppedd 22.91 V for -19

ut for PVDF (Dd to impact foractual voltage

nd -31°C, the vdropped to 18.6

ature of the dryy further. Furthe

w -35°C since gfor the PVDF

also more appa

e on top of the shows actual ne and

for the PVDF 2 µm thickness g the dry ice in he sample, the metal box and ltage recorded s PVDF DT4-d to 14.65V at -9°C and -26°C

DT4-52 µm un rce at various resonance as

voltage output 66 V. It seems y ice began to ermore, it may lass transition material. The

arent with this


The exlaminated ppolymer mmembrane. material extemperature


Again, steady increthe exceptioin voltage ooutput for th


0

5

10

15

20

25

Volta

ge(V)

0

2

4

6

8

10

2

Volta

ge(V)


xperiment was rpiezoelectric m

membrane, see FEvidently, the

xhibited much e range due to 50

mparison of voltmaterial when


as shown in Fease in voltage oon of 8.16V at -1output. The overhis material as th


21 11 1

PV

2 15 3

PV


repeated using aterial, this timFigure 5 as op

28 µm thick mlower voltage

0% reduction in

tage output for subjected to im


Figure 6, the routput as temper15°C which showrall trend points the temperature c


1 10 19Temperature (°C

VDF DT4 52µm

4 15

Temperature (°C)

VDF DT4 28µm


yet another PVme with a 28 µmpposed to 52 µmmembrane piezo

output at anymaterial volume

PVDF (DT4-28mpact force at voltage resona

representation inrature is decreasews a significant ito an increase inontinues to fall.


26 31 3C)

m

20 26 3

)

m

2 µm un

VDF un m thick m thick oelectric y given e.

8 µm un various

ance as

ndicates ed, with increase n energy

8 µm un

32

30

Aincremateresondistriresonhost energshowlowe

Fig. lamintempcaptu

Fig. lamin

T

matethe Pvoltaincreprevi

HlargePVDmatemaxisubjeof thtermechargin m

0

5

10

15

20

25

Volta

ge(V)

As shown in Figease as a result oerial PVDF LDnance increase wibution is clearlynance could be structure, since

gy output due tows a gradual incered.


peratures. Abovured by the picos

8. Comparison nated) piezoelec

The final expererial was on the PVDF batch. Fage output and aeases with the riously obtained. However, the Lest amount of vo

DF material conerials ability to imum capacity ected to given sthe materials voed “dead” regioge from the activ

measured voltag

0

5

0

5

0

5

20 4

gure 7, an overof temperature rDT4-28 µm (lamwas more prominy visible. The dthe result of lamlaminated piezo

o increase in matrease in voltage

of voltage outpwhen subjected


of voltage outp

ctric material at v

riment conductelaminated (LDT

Figure 9 and Fis can be translatreduction of te

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completely “chwith no loss o

tress is only ablelume and the ron. Hence, the ve regions, whic

ge output. For

2 11

Temperat

PVDF LDT4

rall maximum vreduction for theminated). Here,nent and that rep

distinct increase mination on eithoelectric materiaterial stiffness. Ae output as the t

put for PVDF d to impact foractual voltage

put for PVDF various temperat

ed using PVDFT1-28 µm) shortigure 10 indicated, the voltage mperature, simi

terial seemed tocomparison to t

is may be due harge” the memf energy, i.e. lae to charge certaremainder of thdead regions dch results in oveexample, when

18 23

ture (°C)

28µm

voltage output e piezoelectric , the voltage peatability and in the voltage

her side of the al increases its Again Figure 8 temperature is

(LDT4-28 µm rce at various resonance as

(LDT4-28 µm tures

piezoelectric t sample from tes maximum and resonance ilar to results

o produce the the rest of the

to the short mbrane to its arger samples ain percentage he material is draw electrical erall reduction n considering

27 31

dropping a ripples genbank with tend to dim


Fig. 10. Colaminated)

3.2 P

The ou

voltage outpiezoelectriranging frotemperatureincrease, seenergy outpfinally at 1However, adrop margin-30°C, althagain. Furthincreased vcould be thtransforminmass to rebhighlighted

0

20

40

60

80

100

20

Volta

ge(V)

known mass frnerated in the sm

relative ease, wminish before it re

mparison of vomaterial when


omparison of vopiezoelectric ma

PP

utput voltage dtput. Figure 11 ic material of 65om room to -33e is reduced, oee Figure 12 for put resulted from7.1V when the

as reflected in Finally when the though an increahermore, reductvoltage output fhe result of the mng into a brittle bound and caused in the results.

0 12 2,5

PVD

from a fixed heimaller pond will whereas ripples ieaches the banks

ltage output forsubjected to im


oltage output foaterial at various

discussed here shows the volt

5 µm thickness a3°C. The figureverall maximumcomparison. A

m 9.13V at 20°Csample tempera

igure 12, the voltemperature fell ase in energy ion in temperatufrequency. The metallic containestructure, hence

e vibration in the

3 8 14

Temperature ( C

DF LDT1 28µm

ight into the poreach the edges

in the larger pos.

r PVDF (LDT1mpact force at voltage resona

r PVDF (LDT1s temperatures

are for the matage output usinat various tempee indicates thatm voltage is sh

gradual increasC (room temperaature dropped totage output manto -3.5°C and asoutput increaseure has also resuincrease in fre

er which was gre allowing the de metal, thus thi

4 18 25

C)

m

ond, the s of the

ond will

1-28 µm various

ance as

1-28 µm

aximum ng a PP eratures t as the hown to e in the

ature) to o -33°C. naged to s low as ed once ulted in equency radually dropped is being

30

3.2. PP





Research paper360


I. Patel,E. Siores


Fig. mateAbovpicos

Fig. piezo

3

Fshowembeand Pincremateminimpolymrigid

Fig. whenrepresoftw

0

5

10

15

20

Volta

ge(V)

11. Comparisonerial when subjeve represents acscope software

12. Comparisonoelectric materia

3.3 PZT

Figure 13 represws that PZT edded in a polymPVDF material,

eased voltage oerial, the voltagemal negative cmer. This couldmaterial, and th

13. Comparisonn subjected to iesents actual volware

0

5

0

5

0

20 15

n of voltage outpcted to impact fctual voltage re

n of voltage outpal at various temp

ents voltage out250 µm diam

mer matrix follo, where a reductoutput. With the resonance also

cycle produced d be explained dhus, minimising

n of voltage outpmpact force at ltage resonance

3 3,5 1

Temperat

PP 65µ

put for Polypropyforce at various esonance as cap

put for polypropyperatures

tput versus tempmeter piezoelecows similar trendtion in temperate PZT 250 µmincreases, howecompared to t

due to PZT beinrebound.

put for PZT 250various temperas captured by

2 18 26

ture (°C)

µm

ylene (65 µm) temperatures.

ptured by the

ylene (65 µm)

perature which ctric material d to that of PP ture results in

m piezoelectric ever, there is a the foam and ng much more

0 µm material atures. Above the picoscope

30 33

Furtherthe remain(with the exand repeatatransfer of affecting thfrom Figurethe reductioslightly dro

Fig. 14. piezoelectri

As expa metallic in compariof metal svibrations, The metal amplitude ewas an addresulting ingradual incwith margiand -15°C,

Final epiezoelectrconsisted owith the material acthe mass sbehaved asmaterial hpiezoelectrsingle layerincrease inresult of independencancel eachgenerated. was observsee Figure

0

2

4

6

8

10

12

14

1Vo

ltage

(V)

rmore, after thnder of the peaxception of poinable conditions.vibration from t

he piezoelectric e 14, the actual on of temperatu

ops to 10.60 V fr

Comparison ofic material at var

pected, PZT bimshim in betwe

son to 250 µm shim in between

resulting in hishim may haveeffect and lack ditional parame

n out of phase screase in energynal drop in voltrespectively. experiment wa

ric structure, seeof 4 individual certain adhesiv

cted independenstruck the mats a single unit

had 100% and ric active mater material, respen the total ovthe 4 indepen

ntly and the colh other to a certHowever, an o

ved as the tempe18.

19 14

P

he initial maxks that followent -22°C), indica

This may also the metal contaimaterial. Once trend for voltag

ure, with the excrom 11.06 at 0°C

f voltage outprious temperatur

morph (two pieeen) exhibited piezoelectric mn the duel layeigher voltage oalso contributedof repeatability

eter introduced signal generationy output as a redtage from 16.31

as performed oe Figure 17. Thstrips attached

ve from the mntly in terms of erial, whereas . Although the

200% increaserial in comparectively, it faile

verall voltage ondent piezoeleclective voltage ain extent, i.e. o

overall increase erature was decr

0 12

Temperature (°C

PZT 250µm

ximum voltageed gradually deating much morsuggest the con

ner as it froze aagain, as can b

ge output increasception of -12°CC.

put for PZT 2res

ezoelectric layehigher voltage

material due to aers which exagoutput, see Figud to the larger ny since the metinto the host stn. Figure 16 repduction of temp1 V to 12.63 V

on the PZT 4he piezoelectric

in stack configmanufacturers. data acquisitionthe bimorph m

e 4 layer piezose in the volurison to bimorpd to exhibit signoutput. This wctric materials signals were fo

out of phase signin the voltage

reased below su

22

C)

e peak, ecreased e stable ntrolled

and thus be seen ses with C which

250 µm

rs with output

addition ggerated ure 15.

negative al shim tructure presents erature, at -9°C

4 layer sample

guration The 4

n when material electric

ume of ph and nificant

was the acting

orced to nal was output

ub-zero,

30

Fig. whenrepresoftw

Fig. piezo

Fig. 1subjeactua

Fig. piezo

1

1

2

Volta

ge(V)

0

4

8

12

16

Volta

ge(V)


16. Comparisoelectric materia

17. Comparison oected to impact fal voltage resonan


0

5

10

15

20

18 12

0

4

8

2

6

18 15


on of voltage al at various temp

of voltage outputforce at various tnce as captured by

son of voltageal at various temp

2 3 9

Temperat

PZT Bimo

6 5

Temperat

PZT 4 Lay

put for PZT Bimvarious temperas captured by

output for Pperatures

t for PZT 4 layer temperatures. Aby the picoscope s

e output for Pperatures

9 15 21

ture (°C)

orph

12 19

ure (°C)

yer

morph material atures. Above the picoscope

PZT Bimorph

material when bove represents software

PZT 4 layer

1 30

26 32

4. Con

Impact the tempernormal roomat various piezoelectrior multi layat certain marginally

This wvoltage ma250 µm piedue to the sthe 4 layer terms of poPVDF samvoltage outpDT4-52 µmmaterial voplace due tmaterial and(un-laminatThis also inoutput frompiezoelectri

The sucommercialshorter (LDenergy harflexibility frand cost. Thtemperature/ stacking otransfer mob

Referen [1] H.A.

harves[2] E. H

supply[3] T. St

System[4] L.M.

A piedeviceand St

[5] I. Patebased Senso

[6] E.R. Proce“Wear

[7] J. KyParasiIEEE Pittsbu

ncluding reanalysis at sub

rature of the mm temperature totemperatures in

ic materials, PPyer and for any gsubzero tempedecreases but qu

was apparent witanifested betweezoelectric materisingle layer, whsample proved

ositive and negamples, LDT1-28

put due to compm (un-laminated)olume. The lamito kapton laminad thus, raises theted) piezoelectricndicates that the

m both impact andic membrane. ubzero experimel / domestic applDT4-28 µm) lamrvesting applicafrom engineeringhe increase in v

e could be explaiof atoms and mobility when inter

nces Sodano, G. P

sting advances aHausler, E. Stei

y with PVDF filtarner, Human-ms Journal 35/3-Swallow, J.K.

ezoelectric fibree for potential wtructures 17 (200el, E. Siores, Utipiezoelectric m

ors and ActuatorsPost, M. Orth,edings of therable Computersymissis, C. Keitic power harveInternational S

urg, 1998, 132-1

emarks b zero temperatumaterial is allowo around -30°C, ntervals general, PVDF and PZgiven material ceratures intervaluickly regains esth all PZT samen -12°C and -ial displayed by ereas the bimorpto be slightly i

ative amplitude oµm (shorter ver

plete charge of th) sample becausinated (LDT4-28ate which increae energy output. c material showee kapton laminad vibration analy

ents concluded lication needs, it

minated PVDF ation. This wilg prospective, as oltage output as ined due to the eolecules, and thurnal charge is gen

Park, D.J. Inmaand applications,in, Implantablem, Ferroelectric-powered weara-4 (1996) 618-62Luo, E. Siores

e composite bawearable applica08) 025017. ilisation of smar

materials for scavs A 159 (2010) 2, Smart fabric e 1st Internatis”, Cambridge, 1endall, J. Paradesting in shoes, ymposium on “139.

ures established wed to decreasthe voltage asce

lly increases foZT, regardless oonfiguration. Hols, the voltage scalating trend.

mples where a -15°C. Moreovefar the best repeaph with metal shinconsistence maoutput. With regrsion) exhibited he material, follose of 100% incr8 µm) was in thases the stiffnessFinally, the DT4ed lesser energy ate increases the ysis, but also prot

that in order tt is advantageoumaterial for mall also ensure well as reducinga result of redu

enhanced closed ps, increases the enerated.

an, Review of , e physiological s 60 (1984) 277able computing28. s, I. Patel, D.

ased energy harations, Smart M

rt polymers and cvenging wasted 213-218. or wearable c

ional Symposiu1997, 167-168. diso, N. GershProceedings of

“Wearable Comp

that as se from ertained or all 3 f single owever,

output drop in er, PZT atability him and ainly in gards to

largest owed by rease in he third s of the 4-28 µm

output. energy

tects the

to fulfil s to use aximum

greater g weight uction in packing electron

power

power -282.

g, IBM

Dodds, rvesting

Materials

ceramic energy,

lothing, um on

henfeld, f the 2nd puters”,

3.3. PZt





361

Properties


Fig. mateAbovpicos

Fig. piezo

3

Fshowembeand Pincremateminimpolymrigid

Fig. whenrepresoftw

0

5

10

15

20

Volta

ge(V)

11. Comparisonerial when subjeve represents acscope software

12. Comparisonoelectric materia

3.3 PZT

Figure 13 represws that PZT edded in a polymPVDF material,

eased voltage oerial, the voltagemal negative cmer. This couldmaterial, and th


0

5

0

5

0

20 15

n of voltage outpcted to impact fctual voltage re

n of voltage outpal at various temp

ents voltage out250 µm diam

mer matrix follo, where a reductoutput. With the resonance also

cycle produced d be explained dhus, minimising


3 3,5 1

Temperat

PP 65µ

put for Polypropyforce at various esonance as cap

put for polypropyperatures

tput versus tempmeter piezoelecows similar trendtion in temperate PZT 250 µmincreases, howecompared to t

due to PZT beinrebound.

put for PZT 250various temperas captured by

2 18 26

ture (°C)

µm

ylene (65 µm) temperatures.

ptured by the

ylene (65 µm)

perature which ctric material d to that of PP ture results in

m piezoelectric ever, there is a the foam and ng much more

0 µm material atures. Above the picoscope

30 33

Furtherthe remain(with the exand repeatatransfer of affecting thfrom Figurethe reductioslightly dro

Fig. 14. piezoelectri

As expa metallic in compariof metal svibrations, The metal amplitude ewas an addresulting ingradual incwith margiand -15°C,

Final epiezoelectrconsisted owith the material acthe mass sbehaved asmaterial hpiezoelectrsingle layerincrease inresult of independencancel eachgenerated. was observsee Figure

0

2

4

6

8

10

12

14

1

Volta

ge(V)

rmore, after thnder of the peaxception of poinable conditions.vibration from t

he piezoelectric e 14, the actual on of temperatu

ops to 10.60 V fr

Comparison ofic material at var

pected, PZT bimshim in betwe

son to 250 µm shim in between

resulting in hishim may haveeffect and lack ditional parame

n out of phase screase in energynal drop in voltrespectively. experiment wa

ric structure, seeof 4 individual certain adhesiv

cted independenstruck the mats a single unit

had 100% and ric active mater material, respen the total ovthe 4 indepen

ntly and the colh other to a certHowever, an o

ved as the tempe18.

19 14

P

he initial maxks that followent -22°C), indica

This may also the metal contaimaterial. Once trend for voltag

ure, with the excrom 11.06 at 0°C

f voltage outprious temperatur

morph (two pieeen) exhibited piezoelectric mn the duel layeigher voltage oalso contributedof repeatability

eter introduced signal generationy output as a redtage from 16.31

as performed oe Figure 17. Thstrips attached

ve from the mntly in terms of erial, whereas . Although the

200% increaserial in comparectively, it faile

verall voltage ondent piezoeleclective voltage ain extent, i.e. o

overall increase erature was decr

0 12

Temperature (°C

PZT 250µm

ximum voltageed gradually deating much morsuggest the con

ner as it froze aagain, as can b

ge output increasception of -12°CC.

put for PZT 2res

ezoelectric layehigher voltage

material due to aers which exagoutput, see Figud to the larger ny since the metinto the host stn. Figure 16 repduction of temp1 V to 12.63 V

on the PZT 4he piezoelectric

in stack configmanufacturers. data acquisitionthe bimorph m

e 4 layer piezose in the volurison to bimorpd to exhibit signoutput. This wctric materials signals were fo

out of phase signin the voltage

reased below su

22

C)

e peak, ecreased e stable ntrolled

and thus be seen ses with C which

250 µm

rs with output

addition ggerated ure 15.

negative al shim tructure presents erature, at -9°C

4 layer sample

guration The 4

n when material electric

ume of ph and nificant

was the acting

orced to nal was output

ub-zero,

30

Fig. whenrepresoftw

Fig. piezo

Fig. 1subjeactua

Fig. piezo

1

1

2

Volta

ge(V)

0

4

8

12

16

Volta

ge(V)



17. Comparison oected to impact fal voltage resonan


0

5

10

15

20

18 12

0

4

8

2

6

18 15


on of voltage al at various temp

of voltage outputforce at various tnce as captured by

son of voltageal at various temp

2 3 9

Temperat

PZT Bimo

6 5

Temperat

PZT 4 Lay

put for PZT Bimvarious temperas captured by

output for Pperatures

t for PZT 4 layer temperatures. Aby the picoscope s

e output for Pperatures

9 15 21

ture (°C)

orph

12 19

ure (°C)

yer

morph material atures. Above the picoscope

PZT Bimorph

material when bove represents software

PZT 4 layer

1 30

26 32

4. Con

Impact the tempernormal roomat various piezoelectrior multi layat certain marginally

This wvoltage ma250 µm piedue to the sthe 4 layer terms of poPVDF samvoltage outpDT4-52 µmmaterial voplace due tmaterial and(un-laminatThis also inoutput frompiezoelectri

The sucommercialshorter (LDenergy harflexibility frand cost. Thtemperature/ stacking otransfer mob

Referen [1] H.A.

harves[2] E. H

supply[3] T. St

System[4] L.M.

A piedeviceand St

[5] I. Patebased Senso

[6] E.R. Proce“Wear

[7] J. KyParasiIEEE Pittsbu

ncluding reanalysis at sub

rature of the mm temperature totemperatures in

ic materials, PPyer and for any gsubzero tempedecreases but qu

was apparent witanifested betweezoelectric materisingle layer, whsample proved

ositive and negamples, LDT1-28

put due to compm (un-laminated)olume. The lamito kapton laminad thus, raises theted) piezoelectricndicates that the

m both impact andic membrane. ubzero experimel / domestic applDT4-28 µm) lamrvesting applicafrom engineeringhe increase in v

e could be explaiof atoms and mobility when inter

nces Sodano, G. P

sting advances aHausler, E. Stei

y with PVDF filtarner, Human-ms Journal 35/3-Swallow, J.K.

ezoelectric fibree for potential wtructures 17 (200el, E. Siores, Utipiezoelectric m

ors and ActuatorsPost, M. Orth,edings of therable Computersymissis, C. Keitic power harveInternational S

urg, 1998, 132-1

emarks b zero temperatumaterial is allowo around -30°C, ntervals general, PVDF and PZgiven material ceratures intervaluickly regains esth all PZT samen -12°C and -ial displayed by ereas the bimorpto be slightly i

ative amplitude oµm (shorter ver

plete charge of th) sample becausinated (LDT4-28ate which increae energy output. c material showee kapton laminad vibration analy

ents concluded lication needs, it

minated PVDF ation. This wilg prospective, as oltage output as ined due to the eolecules, and thurnal charge is gen

Park, D.J. Inmaand applications,in, Implantablem, Ferroelectric-powered weara-4 (1996) 618-62Luo, E. Siores

e composite bawearable applica08) 025017. ilisation of smar

materials for scavs A 159 (2010) 2, Smart fabric e 1st Internatis”, Cambridge, 1endall, J. Paradesting in shoes, ymposium on “139.

ures established wed to decreasthe voltage asce

lly increases foZT, regardless oonfiguration. Hols, the voltage scalating trend.

mples where a -15°C. Moreovefar the best repeaph with metal shinconsistence maoutput. With regrsion) exhibited he material, follose of 100% incr8 µm) was in thases the stiffnessFinally, the DT4ed lesser energy ate increases the ysis, but also prot

that in order tt is advantageoumaterial for mall also ensure well as reducinga result of redu

enhanced closed ps, increases the enerated.

an, Review of , e physiological s 60 (1984) 277able computing28. s, I. Patel, D.

ased energy harations, Smart M

rt polymers and cvenging wasted 213-218. or wearable c

ional Symposiu1997, 167-168. diso, N. GershProceedings of

“Wearable Comp

that as se from ertained or all 3 f single owever,

output drop in er, PZT atability him and ainly in gards to

largest owed by rease in he third s of the 4-28 µm

output. energy

tects the

to fulfil s to use aximum

greater g weight uction in packing electron

power

power -282.

g, IBM

Dodds, rvesting

Materials

ceramic energy,

lothing, um on

henfeld, f the 2nd puters”,

4. concluding remarks

references





Research paper362 READING DIRECT: www.journalamme.org

Journal of Achievements in Materials and Manufacturing Engineering Volume 55 Issue 2 December 2012

[8] N.S. Shenck, A demonstration of useful electric energy generation from piezoceramics in a shoe, MSc Thesis Proposal, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 1999.M.J. Ramsey, W.W. Clark, Piezoelectric energy harvesting for bio MEMS applications, Proceedings of SPIE 8th Annual Smart Materials and Structures Conference, Industrial and Commercial Applications of Smart Structures Technologies, Newport Beach 4332 (2001) 429-438.

[9] G.K. Ottman, H. Hofmann, A.C. Bhatt, G.A. Lesieutre, Adaptive piezoelectric energy harvesting circuit for wireless, Remote Power Supply, IEEE Transactions on Power Electronics 17/5 (2002) 669-676.

[10] H. Hofmann, G.K. Ottman, G.A. Lesieutre, Optimized piezoelectric energy circuit using step-down converter in discontinuous conduction mode, IEEE Transactions on Power Electronics 18/2 (2002) 696-703.

[11] H.A. Sodano, G. Park, D.J. Leo, D.J. Inman, Use of piezoelectric energy harvesting devices for charging batteries, Proceedings of the SPIE 10th Annual International Symposium on “Smart Structures and Materials”, Smart Sensor Technology and Measurement Systems, San Diego 5050 (2003) 101-108.

[12] H.A. Sodano, G. Park, D.J. Inman, An investigation into the performance of macro-fiber composites for sensing and structural vibration applications, Mechanical Systems and Signal Processing, 2003 (in press).

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http://www.readingdirect.org

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Evaluation of piezoelectric smart materials …jamme.acmsse.h2.pl/papers_vol55_2/58221.pdffixed to its ribs and spontaneous breathing led to a peak voltage of 18 V, which corresponded