HARNESSING ENERGY FROM MICRO VIBRATION USING SMART

MATERIALS

AMEIRUL AZRAIE BIN MUSTADZA

A project report submitted in partial fulfillment of the

requirements for the award of the degree of

Master of Engineering (Mechanical)

Faculty of Mechanical Engineering

Universiti Teknologi Malaysia

JANUARY 2012

iii

To my beloved wife, Fara Fatihah who believes in me even though I find it difficult

to do so myself, my adorable daughter Puteh ‘Arissa, who gives me strength to

complete this thesis and my parents, Mustadza and Noorfah who always believe in

me and guide me in all my pursuits.

iv

ACKNOWLEDGEMENT

First and foremost, the author would like to thank Allah, the Most Beneficent

and the Most Merciful for His blessings throughout the process of completing this

project.

The author would like to express his deepest appreciation to his project

supervisor, Assoc. Prof. Dr. Intan Zaurah Binti Mat Darus for all the advice,

guidance, support and encouragement throughout this project and in the preparation

of this thesis.

The author would like to extend his appreciation to his beloved wife Fara

Fatihah Binti Ibrahim, father Mustadza Bin Md. Yusop, mother Noorfah Binti Senusi

and his family for their support and encouragement which has indeed inspired the

author to complete this project.

Lastly, the author would like to thank all his colleagues who have contributed

in one way or another, directly or indirectly in the process of carrying out this

project.

v

ABSTRACT

Energy harnessing for the purpose of powering low power electronic devices

has received much attention in the last few years. By harnessing ambient energy

from the environment it will eliminate the need for batteries and supplying the

portable electronic devices such as cell phones, laptops and MP3 players with infinite

amount of energy. The ambient energy that can be harnessed to generate electricity

comes from a wide range of sources but vibration energy shows a promising amount

of power generation. In this study, conversion of mechanical vibration into

electricity using piezoelectric vibration-to-electricity converter is undertaken with a

focus to quantify the amount of power that can be generated and identify electronic

devices that can fully utilize this power. The study is divided into two main parts

which are simulation from the forced vibration data and laboratory experiment on

vibrating mechanical equipments such as turbine and centrifugal pump. The

simulation result shows that as the acceleration magnitude increases, the average

direct voltage also increases from 4.5 mV to 8.1 mV and the average power output

that could be harnessed also increases from 22.5 µW to 40.5 µW. Similarly, the

experimental result shows that for the turbine, as the speed of the turbine increases

from 1150 rpm to 1450 rpm, the average power produced increases from 1.63 µW to

2.02 µW. Also, for the centrifugal pump, as the speed increases from 1700 rpm to

1900 rpm, the average power produced increases from 3.02 µW to 3.06 µW. The

experimental results also revealed that within 30 minutes, 1.84 µW of energy could

be harnessed from the vibration of the turbine at speed of 1450 rpm while 3.06 µW

of energy could be harnessed from the vibration of the centrifugal pump at speed of

1900 rpm. This power output is sufficient for low-powered wireless sensor networks

in silent mode which can be used in variety of applications as indicated in the

previous literatures.

vi

ABSTRAK

Penggemblengan tenaga bagi tujuan membekalkan kuasa kepada peranti

elektronik kuasa rendah telah mendapat perhatian sejak beberapa tahun kebelakangan

ini. Dengan memanfaatkan tenaga ambien dari persekitaran, ia akan dapat

mengurangkan kebergantungan kepada bateri dan membekalkan alat-alat elektronik

mudah alih seperti telefon bimbit, komputer riba dan pemain MP3 dengan jumlah

tenaga yang tidak terbatas. Tenaga ambien yang boleh dimanfaatkan untuk menjana

tenaga elektrik datang dari pelbagai sumber tetapi tenaga getaran menunjukkan

potensi jumlah penjanaan kuasa. Dalam kajian ini, penukaran getaran mekanikal

kepada tenaga elektrik yang menggunakan piezoelektrik penukar getaran-kepada-

elektrik dilaksanakan dengan fokus untuk mengira jumlah kuasa yang boleh dijana

dan mengenal pasti peranti elektronik yang boleh menggunakan kuasa ini

sepenuhnya. Kajian ini terbahagi kepada dua bahagian utama iaitu simulasi dari data

getaran paksa dan eksperimen makmal ke atas peralatan mekanikal yang bergetar

seperti turbin dan pam empar. Keputusan simulasi menunjukkan bahawa dengan

kenaikan magnitud pecutan, voltan langsung purata juga meningkat daripada 4.5 mV

kepada 8.1 mV dan kuasa purata yang boleh dimanfaatkan juga meningkat daripada

22.5 μW kepada 40.5 μW. Begitu juga, hasil eksperimen menunjukkan bahawa

untuk turbin, apabila kelajuan turbin meningkat dari 1150 rpm ke 1450 rpm, kuasa

purata yang dihasilkan meningkat dari 1.63 μW ke 2.02 μW. Di samping itu, untuk

pam empar, apabila kelajuan meningkat dari 1700 rpm ke 1900 rpm, kuasa purata

yang dihasilkan meningkat dari 3.02 μW ke 3.06 μW. Keputusan eksperimen juga

mendedahkan bahawa dalam tempoh 30 minit, 1.84 μW tenaga boleh dimanfaatkan

dari getaran turbin pada kelajuan 1450 rpm manakala 3.06 μW tenaga boleh

dimanfaatkan dari getaran pam empar pada kelajuan 1900 rpm. Kuasa ini adalah

mencukupi untuk rangkaian sensor tanpa wayar berkuasa rendah dalam mod senyap

yang boleh digunakan dalam pelbagai aplikasi seperti yang dinyatakan dalam

penulisan kajian terdahulu.

vii

TABLE OF CONTENTS

CHAPTER TITLE PAGE

DECLARATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

TABLE OF CONTENTS vii

LIST OF TABLES x

LIST OF FIGURES xi

LIST OF SYMBOLS xiv

LIST OF ABBREVIATIONS xvi

LIST OF APPENDICES xvii

1 INTRODUCTION 1

1.1 Introduction 1

1.2 Problem Statement 3

1.3 Objectives 4

1.4 Scopes 4

1.5 Research Methodology 4

1.6 Project Activities 7

2 LITERATURE REVIEW 9

2.1 Energy Sources 9

2.1.1 Human Body 10

2.1.2 Solar 11

2.1.3 Temperature Gradient 11

viii

2.1.4 Air Flow 11

2.1.5 Acoustic Noise 13

2.1.6 Vibration 13

2.1.7 Summary of Viable Power Source 14

2.2 Sources of Vibration 14

2.3 Methods of Converting Vibration into Electricity 15

2.3.1 Electromagnetic (Inductive) Conversion 15

2.3.2 Electrostatic (Capacitive) Conversion 19

2.3.3 Piezoelectric Conversion 21

2.3.4 Comparison of Energy Density 24

2.3.5 Summary of Conversion Mechanisms 25

2.4 Piezoelectricity 26

2.5 Vibration Energy Harnessing using Piezoelectric

Materials

27

2.6 Energy Storage Devices 30

2.7 Summary 31

3 METHODOLOGY 33

3.1 Simulation Setup 33

3.1.1 Piezoelectric Sensing Element 33

3.1.2 Harnessing Circuit 34

3.2 Data Acquisition System (DAQ) 37

3.2.1 Flow of Information in DAQ 38

3.3 Test Equipment 40

3.3.1 Vibrating Mechanical Equipments 40

3.3.2 Piezoelectric Sensor P-876.A12 DuraAct 41

3.3.3 NI Compact-data Acquisition Unit 42

3.3.6.1 NI-9234 Module 42

3.3.4 Processor and LabVIEW 43

3.3.5 Harnessing Circuit 44

3.4 Energy Storage Selection 45

3.5 Experimental Setup 46

3.5.1 Experimental Procedure 46

ix

4 RESULTS AND DISCUSSION 48

4.1 Simulation Result 48

4.2 Experimental Result 53

4.2.1 Turbine 53

4.2.1.1 Accumulated Energy 55

4.2.2 Centrifugal Pump 55

4.2.2.1 Accumulated Energy 57

4.3 Overall Analysis 57

5 CONCLUSION AND RECOMMENDATIONS 59

5.1 Conclusion 59

5.2 Recommendations 60

REFERENCES 61

Appendices A - B 65 - 66

x

LIST OF TABLES

TABLE NO. TITLE PAGE

1.1 Comparison of potential energy sources with a fixed

level of power generation and a fixed amount of energy

storage

2

2.1 Acceleration (m/s2 ) magnitude and frequency of

fundamental vibration mode for various sources

(Roundy et al., 2003)

14

2.2 Summary of maximum energy densities for three types

of conversion mechanisms (Roundy and Wright, 2004)

24

2.3 Comparison summary of three conversion mechanisms 25

2.4 Comparison of piezoelectric materials (Gonzalez et al.,

2002)

27

4.1 Summary of simulation results 53

4.2 Summary of actual experiment results 58

xi

LIST OF FIGURES

FIGURE NO. TITLE PAGE

1.1 Methodology of the study 6

1.2 Gantt chart for Master Project 1 7

1.3 Gantt chart for Master Project 2 8

2.1 Two approaches to unobtrusive 31-mode piezoelectric

energy harnessing in shoes: a PVDF stave under the

ball of the foot and a PZT dimorph under the heel

(Shenck and Paradiso, 2001)

10

2.2 Schematic and pictures of the fabricated electric

energy generator. (a) Schematic showing the

arrangement of the bimorph transducers. (b)

Photograph of the fabricated prototype. (c) Loading of

the bimorphs using rectangular hooks (Chen et al.,

2006)

12

2.3 Schematic of overall AEH (Horowitz et al., 2006) 13

2.4 Schematic diagram of linear inertial generator

(Williams and Yates, 1996)

17

2.5 Schematic cross-section of micromachined generator

(Williams et al., 2001)

18

2.6 Electromagnetic conversion device (Amirtharajah and

Chandrakasan, 1998)

18

2.7 In-plane overlap (Roundy et al., 2003) 20

2.8 In-plane gap closing (Roundy et al., 2003) 20

2.9 Out-of-plane gap closing (Roundy et al., 2003) 20

2.10 Illustration of 33 mode and 31 mode operation for

piezoelectric material (Roundy et al., 2003)

22

2.11 Equivalent circuit for a piezoelectric generator

xii

(Roundy et al., 2003) 23

2.12 Concept of vibration energy harnessing using

piezoelectric materials

27

2.13 Experimental setup showing a Quick Pack QP40N

attached to the shaker and dimensions of beam when

one end is clamped (Sodano et al., 2004)

28

2.14 Size and layout of the PZT plate (Sodano et al., 2005) 29

2.15 Size and layout of the MFC plate (Sodano et al., 2005) 29

2.16 Size and layout of the Quick Pack actuator (Sodano et

al., 2005)

29

3.1 Block diagram for piezoelectric accelerometer 34

3.2 Sensing element of piezoelectric accelerometer

developed using Matlab SIMULINK

34

3.3 Non-adaptive harnessing circuit (Mingjie and Wei-

Hsin, 2005)

35

3.4 Non-adaptive harnessing circuit developed using

Matlab SIMULINK

36

3.5 Block diagram of data acquisition system 37

3.6 Experimental setup layout 39

3.7 Turbine 40

3.8 Centrifugal pump 41

3.9 Piezoelectric sensor P-876.A12 DuraAct 41

3.10 NI compact-data acquisition unit 42

3.11 NI-9234 module 43

3.12 Processor with LabVIEW software 44

3.13 Harnessing circuit 45

3.14 Capacitor 45

3.15 Experimental setup 46

4.1 Acceleration versus time at different amplitude of

(a) 0.05 Vpp, (b) 0.10 Vpp and (c) 0.15 Vpp

50

4.2 Voltage versus time at different amplitude of

(a) 0.05 Vpp, (b) 0.10 Vpp and (c) 0.15 Vpp

52

xiii

4.3 Voltage versus time for the turbine at speed of

1150 rpm

53

4.4 Current versus time for the turbine at speed of

1150 rpm

54

4.5 Voltage versus time for the turbine at speed of

1450 rpm

54

4.6 Current versus time for the turbine at speed of

1450 rpm

54

4.7 The amount of voltage accumulated and stored in the

capacitor for the turbine at speed of 1450 rpm

55

4.8 Voltage versus time for the centrifugal pump at speed

of 1700 rpm

56

4.9 Current versus time for the centrifugal pump at speed

of 1700 rpm

56

4.10 Voltage versus time for the centrifugal pump at speed

of 1900 rpm

56

4.11 Current versus time for the centrifugal pump at speed

of 1900 rpm

56

4.12 The amount of voltage accumulated and stored in the

capacitor for the centrifugal pump speed at 1900 rpm

57

xiv

LIST OF SYMBOLS

°C - Celsius

𝛷𝐵 - Magnetic flux

Ω - Ohm

𝛿 - Mechanical strain

𝜀 - Induced emf; Dielectric constant

ε0 - Dielectric constant of free space, Permittivity of free space

𝜇0 - Permeability of free space

𝜎 - Mechanical stress

𝜎𝑦 - Yield stress

A - Ampere

𝑎 - Acceleration

𝐵 - Magnetic field

𝐶 - Capacitance

𝑐 - Elastic constant

𝐷 - Electrical displacement (charge density)

𝑑 - Gap or distance between plates; Piezoelectric strain coefficient

dB - Decibel

𝐸 - Electric field

f - Frequency

Hz - Hertz

I, 𝑖 - Current

k - Coupling coefficient; Piezoelectric constant

𝑙 - Length of one coil (2πr); Length of plate

m - Meter

𝑁 - Number of turns in coil

𝑄 - Charge on capacitor

R - Resistance

xv

rpm - Revolution per minute

s, sec - Second

𝑡 - Thickness

V, Volt - Voltage

Vp

V

- Voltage peak

pp

W - Watt

- Voltage peak-to-peak

𝑤 - Width of plate

𝑌 - Modulus of elasticity (Young’s Modulus)

𝑦 - Distance coil moves through magnetic field

xvi

LIST OF ABBREVIATIONS

A/D - Analog to Digital

AC - Alternate Current

AI - Analog Input

AO - Analog Output

AEH - Acoustic Energy Harvester

BaTiO3

D/A - Digital to Analog

- Barium Tinate

DAQ - Data Acquisition System

DC - Direct Current

DIO - Digital I/O

fpm - feet per minute

HVAC - Heating, Ventilation and Air Conditioning

I/O - Input to Output

IEPE - Integrated Electronic Piezoelectric

MFC - Macro-Fiber Composite

NI - National Instrumentation

PI - Physik Instrumente

PVDF - Polyvinylidene Fluoride

PZT - Lead Zirconate Tinate

PZT-5A - Hard Lead Zirconate Tinate

QP - Quick Pack

RFID - Radio Frequency Identification

xvii

LIST OF APPENDICES

APPENDIX TITLE PAGE

A Properties of piezoelectric patch actuator type

DuraAct P-876.A12 (Physik Instrumente (PI)

GmbH & Co. KG, 2008)

64

B Technical data of piezoelectric patch actuator

type DuraAct (Physik Instrumente (PI) GmbH

& Co. KG, 2008)

65

CHAPTER 1

INTRODUCTION

1.1 Introduction

Over the last 20 years, the continuous development of technology has

significantly reduced the size and increased the function of electronic devices and in

parallel decreased their power consumption (Gonzalez et al., 2002). Nowadays hand

held and portable electronic devices such as cell phones, laptops and MP3 players

provide users with comprehensive functions which include communication,

computing and audio functions. Batteries are commonly used to power the electronic

devices. However, due to its limited capacity, batteries could possibly supply power

only for short lifetime of about one to three years and its significant size and weight

has caused problem to the present hand held and portable devices. This problem has

then led to the rising demand for self-powered electronic devices because the usage

of current battery technology to power electronic devices has become impractical.

The advancement of current technology has helped to fulfill the demand for

self-powered electronics devices by harnessing ambient energy from the

environment, thus eliminating the need for batteries and supplying these electronic

devices with infinite amount of energy. The ambient energy that can be harnessed to

generate electricity is coming from a wide range of sources such as human body

(Shenck and Paradiso, 2001; Starner, 1996) and temperature gradient (Stordeur and

Stark, 1997).

2

Another form of energy sources that has received attention from researchers

for energy harnessing is vibration (Chiu and Tseng, 2008; Glynne-Jones et al., 2004;

Lefeuvre et al., 2006; Roundy and Wright, 2004; Roundy et al., 2002; Roundy et al.,

2003; Williams et al., 2001; Williams and Yates, 1996; Yen and Lang, 2006) which

can be observed in buildings, factories, vehicles, industrial machineries and

household appliances. Typically, vibration energy can be converted into electric

energy by three methods, namely electromagnetic (inductive) (Glynne-Jones et al.,

2004; Williams et al., 2001; Williams and Yates, 1996), electrostatic (capacitive)

(Chiu and Tseng, 2008; Roundy et al., 2002; Yen and Lang, 2006) and piezoelectric

conversion (Lefeuvre et al., 2006; Roundy and Wright, 2004; Roundy et al., 2003).

Table 1.1 shows a comparison of potential energy sources with a fixed level of power

generation and a fixed amount of energy storage where all power density values are

normalized to the size of 1 cm3

based on the size of typical wireless sensor nodes

(Rabaey et al., 2002).

Table 1.1: Comparison of potential energy sources with a fixed level of power

generation and a fixed amount of energy storage

Sources

Power Density

(μW/cm3

1 year lifetime

)

Power Density

(μW/cm3

10 year lifetime

)

Solar (outdoors) 15,000 – direct sun

150 – cloudy day

15,000 – direct sun

150 – cloudy day

Solar (indoors) 6 – office desk 6 – office desk

Shoe inserts 330 330

Temperature gradient 15 at 10°C gradient 15 at 10°C gradient

Vibration (electromagnetic conversion) 100 100

Vibration (electrostatic conversion) 50 50

Vibration (piezoelectric conversion) 200 200

Batteries (non-rechargeable lithium) 45 3.5

Batteries (rechargeable lithium) 7 0

Hydrocarbon fuel (micro heat engine) 333 33

Fuel cells 280 28

3

The driving force to harness ambient energy from the environment is mostly

due to the development of wireless sensor and actuator networks where particular

research has been conducted for a project named PicoRadios (Rabaey et al., 2002).

This project aims to develop a small and flexible wireless platform for ubiquitous

wireless data acquisition that minimizes power dissipation. The important

specifications for the power system developed by PicoRadios project researchers are

the total size and average power dissipation of an individual node. The size of a

node must not be larger than 1 cm3

and the target average power dissipation of a

completed node is 100 μW.

The previous research also showed a promising amount of power density

about 50 to 200 μW/cm3 that can be harnessed from vibration energy as illustrates in

Table 1.1. Therefore, the measure of acceptability of an energy harnessing solution

will be its ability to provide 100 μW of power in less than 1cm3. However, this does

not mean that solutions which do not meet this criterion are not worthy of further

exploration but simply that they will not meet the needs of the PicoRadios project.

Thus, the primary criterion to evaluate power sources in this research is power per

volume with a target of at least 100 μW/cm3

.

1.2 Problem Statement

Batteries are type of energy storage devices that commonly used to power

hand held and portable electronic devices as well as implanted biomedical systems.

However, due to its limited capacity, batteries could possibly supply power only for

short lifetime of about one to three years and its significant size and weight has

caused problem to the present hand held and portable devices as well as implanted

biomedical systems. While researchers continuously developed the technology to

increase the energy of storage devices, the solutions are still going to have finite

lifetime. This problem has led to the rising demand for self-powered devices and

systems which can be solved by harnessing energy from a wide range of sources

using a few technique that have been proven can supply infinite amount of power. In

this study, conversion of mechanical vibration into electricity using piezoelectric

4

material is undertaken with a focus to quantify the amount of power that can be

generated and identify electronic devices that can fully utilize this power.

1.3 Objectives

The objective of this project is:

1. To design, simulate and develop an instrumentation system to harness

energy from micro vibration using smart materials.

1.4 Scopes

The scopes of this project are:

1. To conduct a research on the sources of vibration, methodologies and

devices of harnessing energy and its applications.

2. To design and simulate the instrumentation system to harness energy

from vibration and to propose a methodology to store the energy.

3. To develop and fabricate the instrumentation system to harness energy

from vibration using piezoelectric, rectifier and energy storage.

4. To verify and validate thus developed instrumentation system with an

actual source of vibration from vibrating mechanical equipments.

1.5 Research Methodology

The methodologies involved in this study are shown in Figure 1.1. The

project starts by collecting reading materials such as books, journals and technical

papers specifically on sources of vibration, methods of converting ambient vibration

energy into electrical energy, types of piezoelectric material, piezoelectric energy

harnessing circuit and types of energy storage.

5

Research has been done continuously throughout this study to get a better

understanding on the concept of harnessing energy from ambient vibration using

piezoelectric material. Besides, consultation sessions with the project supervisor and

few colleagues who are doing similar research were also held periodically to discuss

any arising issues and problems encountered pertaining to this study.

Based on the research conducted, piezoelectric energy harnessing circuit

selection process was made in order to get the suitable circuit followed by the

selection of a few types of energy storage devices to be used in this study. The study

on piezoelectric energy harnessing has been divided into two main parts which are

(1) simulation of the vibration environment and (2) laboratory experiment on

vibrating mechanical equipments. Both simulation and laboratory experiment will

undergo the same process such as piezoelectric vibration to electricity conversion,

rectification and energy storage.

The simulation in Matlab SIMULINK has been done using vibration data

acquired from experimental study by previous researcher in order to determine the

possible amount of power density output that can be produced for the specific

acceleration input. With the promising amount of power density output produced

during simulation, the laboratory experiment on vibrating mechanical equipments

was conducted for the purpose of quantifying the amount of power that can be

generated by vibrating mechanical equipments and identifying electronic devices that

can fully utilize this power.

6

Figure 1.1: Methodology of the study

Literature Review

Piezoelectric Energy Harnessing

Vibration Environment

Simulation Experiment on Vibrating Mechanical Equipments

Piezoelectric Vibration into Electricity

Conversion

Piezoelectric Vibration into Electricity

Conversion

Rectification

Rectification

Energy Storage

Data Analysis

7

1.6 Project Activities

NO. ACTIVITIES WEEKS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

1 Selection of project title 2 Collecting reading materials 3 Literature review of previous

research

4 Understanding the concept of piezoelectric energy harnessing from vibration

5 Familiarization with Matlab SIMULINK

6 Simulation of vibration environment using data acquired by previous researcher

7 Simulation of energy harnessing 8 Analysis of the results from the

simulation of energy harnessing

9 Report writing 10 Preparation for seminar

presentation

11 Seminar 1

Figure 1.2: Gantt chart for Master Project 1

8

NO. ACTIVITIES WEEKS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

1 Literature review 3 Experimental setup:

Integration and development of data acquisition and instrumentation system

4 Experiment on vibrating mechanical equipments (turbine and centrifugal pump)

6 Analysis of the experimental results

7 Report writing 10 Preparation for seminar

presentation and submission of draft thesis

11 Seminar 2 12 Submission of the thesis

Figure 1.3: Gantt chart for Master Project 2

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