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i DESIGN AND SIMULATION OF ENERGY HARVESTING PIEZOELECTRIC PUZZLE FLOOR MAT USING PIEZOELECTRIC CRYSTALS A thesis presented to the College of Engineering of FEU Institute of Technology In partial fulfillment of the requirement for the Degree of Bachelor of Science In Electronics Engineering By Magluyan, Pamela Kim Donnelle G. Capati, Aubrey Sharmaine M. Postre, Raul Christian M. Engr. Luigi Carlo M. De Jesus Adviser Engr. King Harold H. Recto Faculty in Charge January 2016

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Page 1: Piezoelectric Mat

i

DESIGN AND SIMULATION OF ENERGY HARVESTING

PIEZOELECTRIC PUZZLE FLOOR MAT USING

PIEZOELECTRIC CRYSTALS

A thesis presented to the College of Engineering of

FEU – Institute of Technology

In partial fulfillment of the requirement for the

Degree of Bachelor of Science

In Electronics Engineering

By

Magluyan, Pamela Kim Donnelle G.

Capati, Aubrey Sharmaine M.

Postre, Raul Christian M.

Engr. Luigi Carlo M. De Jesus

Adviser

Engr. King Harold H. Recto

Faculty in Charge

January 2016

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Table of Contents

Page No.

Title Page i

Table of Contents ii

List of Tables iii

List of Figures iv

Chapter 1 Introduction 1

Background of the Study 1

Statement of the Problem 4

General Objective 5

Specific Objective 5

Scope and Delimitation 5

Significance of Study 7

Definition of Terms 8

Chapter 2 Review of Related Works and Literature 9

Review of Related Materials 9

Floor Mats 9

Rubber Sheets 10

Piezoelectric Transducer 11

Piezoelectric Crystals 11

Lithium-ion Battery 11

Full-Wave Rectifier 14

Bridge Full Wave Rectifier 14

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Step – up Chopper 16

Compression Springs 16

Working Theories 16

Energy Harvesting 16

Piezoelectricity 18

How Piezoelectric Effect Works 18

Frequency of Oscillation 19

Cascaded Operational Amplifier Circuit 19

Review of Related Works and Studies 20

Foreign Works and Studies 20

Japan Harnesses Energy from Footsteps 20

A Shoe-Embedded Piezoelectric Energy 22

Harvester for Wearable Sensors

Source of Vibration for Crystal Previous Work 24

Power Generating Sidewalk 24

Power Generating Boots or Shoes 24

Gyms and Workplaces 25

Mobile Keypad and Keyboards 25

Floor Mats, Tiles and Carpets 26

People Powered Dance Clubs 26

Piezoelectric Energy Harvesting 26

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Local Works and Studies 28

In-Wheel Piezoelectric Generator for 28

Lighting Application of Mining Trolleys

Energy-Harnessing Footwear Using 29

Combined Electromechanical And

Piezoelectric Transducers for Charging

Supercapacitors (2009 )

Power Generation for Remote Areas Utilizing 30

Piezoelectric Transducers Harnessing Wind and

Wave Energy (2011)

Chapter 3 Research Methodology 31

Conceptual Framework 31

Block Diagram 32

Schematic Diagram 33

Full-Wave Bridge Rectifier 34

Step-Up Chopper (DC/DC converter) 35

Lithium-ion Battery 35

PCB Layout 36

Flow Chart of Process 37

Test Population 39

Treatment of Data 39

Calculations for the number of trials 39

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Calculation for the Tolerance 40

Testing Procedure 41

Proposed Table for Test Results 41

Proposed Project 43

Ideal Set up 43

Design Considerations of Puzzle Floor Mat 43

References 49

Appendices

Appendix A Chi-Square Critical Values Table 52

Appendix B Bill of Materials 54

Appendix C Gantt Chart 55

Appendix D Average Weight of Students in 56

FEU-Institute of Technology

Appendix E Data of Average Students that Entered 60

the School Premises

Appendix F Consultation Sheet 64

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List of Tables

Figure No. Description Page No.

1 Specifications of Lithium-ion Battery 36

2 Proposed Table for Test Results 41

3 Specifications of Smaller Spring 46

4 Specifications of the Bigger Springs as a support 47

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List of Figures

Figure No. Description Page No.

1 Charging and discharging phenomena in Lithium Ion batteries 13

2 Bridge Full-Wave Rectifier 14

3 Commuters at the Tokyo station walk on a piezoelectric sheet 22

which generates electricity when pedestrians step on it

4 A Shoe-Embedded Piezoelectric Energy Harvester 23

for Wearable Sensor

5 Energy Harvested of Phase 1 and Phase II 28

6 Energy Harvesting Shoe 30

7 Conceptual Framework 31

8 Block Diagram 32

9 Circuit Diagram of the System 33

10 Full-Wave Bridge Rectifier 34

11 Lithium-ion Battery 35

12 PCB Layout 36

13 System Flowchart 37

14 Ideal Set up: A man stepping on the floor mat 43

15 Dimensions of the Puzzle Floor Mat 43

16 Top View of the Puzzle Floor Mat 44

17 Inner Part of the Puzzle Floor Mat 45

18 Comparison of design with respect to vibrations 48

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Chapter I

Introduction

1.1 Background of the Study

Technology has evolved and became more advanced over the past decades and

along with this, the sources of energy that can power up electronics became more

industrialized.

Most energy sources have been depleting due to a great demand from its

increasing population. It is a given fact that the country has been battling with energy

sources that would supply electricity. Manila and other cities had experienced black –

outs or power outages in earlier months of year 2015, specifically April to May because

of the shortage of supply of electricity [1]. Some of the energy sources like Malampaya

have been closed for operating due to weather or climate conditions.

The main energy sources which can be harvested are categorized in mechanical

energy from vibrations, thermal energy, solar energy, biomass and fossil fuels. Another

significant source of energy which is often overlooked is the human body. Human body

can generate a significant amount of energy through footsteps. The human waste foot

energy is being used to produce electricity which is a great evolution in electricity

generation. The average human can take 3,000 – 5,000 steps a day [2]. Some of the

energy wasted when human walks which is in the form of vibrations can be converted

into an electrical energy using Piezoelectric Crystals. Any form of vibration like

footsteps, heartbeats, etc. can generate electricity to activate electronic devices [3]. The

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concept of piezoelectricity can be applied as actuators, transducers, motors, and even

sensors wherein different kinds of materials are used like crystals and strips. The

harvesting of energy of a piezoelectric material is not affected by weather or climate

conditions. Piezoelectric materials generate energy through vibrations or pressure like

footsteps unlike energies from water, sun, wind and etc.

Piezoelectricity are massively used in foreign countries and even in the

Philippines. However, it is mainly used as a transducer in the Philippines. One example

is a microphone where it receives sound waves that are converted into electrical energy

with the use of Piezoelectric Crystals. Piezoelectric Crystals are also used in electric

cigarette lighter. Piezoelectricity has not been used as a large source of energy in the

Philippines. In Japan, piezoelectric floor tiles are used to operate the train – ticketing

systems. These floor tiles converts the vibrations of footsteps into electrical energy in

which the capacity of one footstep can provide enough electrical current to light two 60

– watts bulb for one second [4].

The mass of the person stepping on the floor mat has an effect regarding the

energy output and design consideration. If the person is heavy, the force on the floor mat

is much larger than a light person. On the other hand, the design of floor mat has its

limited weight capacity until it breaks. Using the sample data gathered by the researchers,

the average weight of a person in FEU – Institute of Technology is about 63 kilograms.

Through considering the materials that will be used on the project, the researchers were

able to compute the estimated maximum weight capacity of the floor mat which is 36,993

kilograms.

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Most existing piezoelectric energy harvesting floors used floor tiles. Floor tiles

usually provide a hard surface. Unlike floor mats that are usually made of cloth and

rubber which are soft. An impact is a high force or shock which is applied over a short

period of time once two or more bodies collide whether elastic or inelastic [5]. A theory

in Engineering Mechanics states that impact strength, expressed in amount of energy

absorbed before fracture, decreases per increase in the modulus of elasticity which means

stiff materials will have less impact strength than supple materials [5]. Soft surfaces like

floor mats can produce more oscillations.

Piezoelectric Floor Tiles used ceramic tiles that are heavier than Puzzle Floor Mat

which uses rubber sheets. The mass of the upper layer of the mat which is the rubber

sheets will produce more vibrations than the mass of the ceramic tile. The concept of

frequency of oscillation states that the frequency is inversely proportional to the mass of

the person [6]. The heavier the person, the lower oscillation frequency will be produced.

A low frequency of oscillations will produce longer period of time. Thus, it will have a

greater generated output energy.

Puzzle Floor Mats are connected mats in which the circuit of each mat are

connected in series. Cascading of operational amplifiers is done through connecting each

op – amps in series, thus, increasing the total gain. The gain is directly proportional to

the voltage output [7]. Batteries that are cascaded in series produce a higher voltage

output. The Puzzle Floor Mats are cascaded like cascading op – amps or batteries in

which it increases the voltage output of the whole Puzzle Floor Mat.

With the aid of the facts, the proponents therefore offer to design an Energy-

Harvesting Piezoelectric Puzzle Floor Mat using Piezoelectric Crystals. Instead of floor

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tiles, which are usually made by clay or ceramics, a Puzzle Floor Mat will be used to

generate electrical energy through footsteps. These mats are made of rubber sheets which

are soft and elastic that will produce greater and longer vibrations. Greater and longer

vibrations will produce more energy to be converted.

The added parameters of the proponents’ study are the output energy of the

Piezoelectric Puzzle Floor Mat, installation and cost, weight of the project, as well as the

operability and maintenance. The output energy is the most significant parameter because

it will help in determining which devices it can supply. Installation of these floor mats

are very easy and low cost because it does not need to be installed like floor tiles. It can

just be laid down on the floor and materials that will be used are cheaper and available

in the Philippines. In addition, the frequency of oscillations of the spring has an influence

on the vibrations produced by the project. The weight of the person stepping on the mat

affects the frequency of oscillations which means it is also an important parameter to be

determined. Lastly, the operability and maintenance of the project is very simple since it

can be moved in different places and easy to fix when something is wrong.

1.2 Statement of the Problem

Sources of energy in the Philippines have been diminishing because of a big

demand due to the increasing population in the country. The increasing demand in energy

impels researchers to find a renewable alternative sources. Piezoelectricity is a

technology in harnessing energy used in foreign countries as an alternative source.

Various energy harvesting piezoelectric devices have been developed like Piezoelectric

Floor Tiles.

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The current study will design and localize existing Energy Harvesting

Piezoelectric Puzzle Floor mats. Puzzle Floor Mats will have a soft surface because it is

made of rubber sheets, hence making a longer and larger vibration due to the springs. It

will also be cascaded for a larger energy output. This study will contribute regarding the

problem of declining energy source of the country by using Piezoelectric Puzzle Floor

Mat which harness energy through oscillation.

1.3 General Objective:

To design and simulate the harnessing of energy of a Piezoelectric Puzzle Floor

Mat using Piezoelectric Crystals

1.4 Specific Objective:

To design a rubber Puzzle Floor Mat using Piezoelectric Crystal in converting

mechanical energy to electrical energy

To design a circuit for harnessing, monitoring and storing of the electrical energy

converted

To design a Piezoelectric floor mat which produce larger and longer vibrations

To attain an appropriate energy output of 2.5 Joules per step or higher of the

Puzzle Floor Mat through continuous testing

1.5 Scope and Delimitation

This study will also focus on harvesting energy of the Puzzle Floor Mat that has

a dimension of 20” by 20” by 3”. Each floor mat will have at least 25 piezoelectric

crystals, 25 springs, and another 4 big springs in the inner part of the mat which is beside

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the piezoelectric crystals that will contribute in producing more vibrations. Furthermore,

this study will use a lithium – ion battery with 3.7 volts voltage output.

The generated energy may depend on the weight of the person stepping on the

mat. A maximum of two persons can step on one mat. This study will only be

implemented indoors where many people are passing like building entrance or lobbies.

It can also be moved to different places. This study will monitor the output energy per

step manually using an energy or V/I meter. This study will use plugs that will help in

cascading the floor mats. The exposed jacks and plugs will have specific coverings for

protection against any liquid. However, the floor mat itself should not be soaked too

much with water because materials are not water proof.

The floor mat should be cleaned every day. The most common issue about the

maintenance of rubber floor mats is dirt and small debris which comes from the shoes

and slippers. In cleaning the floor mats, a vacuum or manual gentle scrubbing can be

applied. According to the data we gathered from the clinic, the average weight of the

students that are enrolled in FEU-Institute of Technology is 63kg. The maximum weight

that the floor mat can withstand is 36,993 kg. Therefore, any person can step on the floor

mat.

During testing, the researchers will use a controlled environment. Only one

person, weighing exactly 63 kg, will step on the mat. The person should step on the mat

in his natural way of walking. Moreover, using a controlled environment, the researchers

will be able to determine whether the energy is constant at every trial.

This will not include the study of any kind of tiles. The proponents will use a mat

that is made of rubber sheet which is water resistant in order to avoid any damage in the

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internal parts of the mat in case that it will be wet. In addition, the Puzzle Floor Mat will

not generate energy if the foot is still on the mat unless the foot is removed.

1.6 Significance of Study

The electric energy consumption during 2010 was 64.52 billion kilowatt-hours in

the Philippines, which accelerated from 48.96 billion kilowatt-hours in the year 2013.

The electrical energy consumed in 2014 was 56.84 billion kilowatt-hours which was

ranked as 41st worldwide [9].This study will recommend a way to help lower the

electrical energy consumed annually by utilizing energy that is being dissipated by

human beings regularly. When a person is walking, an energy is formed through footsteps

or vibrations and can be converted into electrical energy. The harvested energy from

human footsteps is large enough to operate an electrical appliance/s and other equipment

which is costless. This project can also be placed in sidewalks to energy the stoplights

and the streetlamp since more footsteps from people walking through the Puzzle Floor

Mat will generate more energy. This study may help energy the lights in the hallways of

the schools and other business companies from the employees or students that are

walking through the Puzzle Floor Mat. Materials that would be used in this study are

locally available which is an advantage since importation of the materials will no longer

be needed.

The future researchers can enhance and develop the features and specifications of

the project as a recommendation. The Piezoelectric Puzzle Floor Mat can be converted

into a water proof floor mat. Floods caused by typhoons are not new in the Philippines.

If it is converted into water proof floor mats, it can be placed in the sidewalks where

pedestrians can walk through it and can still accumulate vibrations regardless of the

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heavy rain and the flood. Moreover, since raindrops can create vibrations when it falls to

the mat, it can still generate energy during rainy days.

Definition of Terms

Piezoelectricity. The concept used in the project wherein it has the ability of a

material to produce an AC voltage from a mechanical energy in a form of vibrations or

stress specifically human footsteps. It also called as piezoelectric effect.

Piezoelectric transducer. It involves a crystal between two plates which form

vibrations and converts the vibrations to weak AC voltage.

Energy harvesting. A method of collecting small amount of energy which is in a form

of heat, light, sound, vibrations or movement. In this study, energy can be harvested

through vibrations and movement and will be used to convert into an electrical energy

using Piezoelectric Puzzle Floor Mat.

Water resistant. The ability to resist the penetration of water in some certain depth

but not entirely and one key feature of the Piezoelectric Floor Mat.

Oscillations. Produced by the vibrations.

Cascade. Connecting the circuit of each Piezoelectric Puzzle Floor Mats in series.

Op – amps. Stands for Operational Amplifiers.

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Chapter II

Review of Related Literature

This chapter discusses the review of related literature about Energy

Harvesting Piezoelectric Puzzle Floor Mats. It explains relevant concepts and materials

involving with the current study to provide the foundation of the proposed study.

2.1 Review of Related Materials

2.1.1 Floor Mats

Floor Mats are standard equipment commonly used in vehicles which

have carpet covering floor. Floor mats are usually flat and typically consist of a

thin layer of lightweight carpeting bonded to a thin layer of polymer type material

that blocks water from getting through [10].

Pros:

Softness and Elasticity of the Floor Mat

Floor Mats are soft and elastic and when a foot steps on it,

it cause vibrations. These vibrations last longer in soft

materials which cause to produce more mechanical energy

that will be converted to electrical energy.

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2.1.2 Rubber Sheets

Rubber sheets are essentially polymers of isoprene. These rubber sheets

are elastic materials that is achieved by thickening and drying the latex from

certain plants which is the milky juice of any of various tropical plants like genera

Hevea and Ficus. Later prepared as sheets [11].

Pros:

Durability

Rubber sheets are strong and resilient against a variety of

conditions. If it installed properly, it can last for a long

time.

Soft

Given the fact that the material is strong and can last for a

long time, rubbers are actually soft.

Water resistant

Rubber materials are not absorbent of water or liquid

which there’s no concerns about damage from simple

liquid spills.

Cons:

Slippage

If rubbers are not textured, it can become slippery when

liquid is spilled on it.

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Dull finish

The appearance of the rubber sheets are unattractive to

many people which is why it is not a common option for

floorings where many people can see it.

Difficulty in Cleaning

Rubbers picks up grease so easy and have a tendency to

discolor when detergents are used for cleaning.

2.1.3 Piezoelectric Transducer

Piezoelectric transducer is a device that converts one type of energy to

another by using the piezoelectric properties of certain crystals or other materials

[12]. It generates an electrical potential or voltage when a force or pressure is

applied onto the piezoelectric device or material. Piezoelectric transducers are

epitome of a good converter of mechanical energy to electrical.

2.1.4 Piezoelectric Crystals

Piezoelectric Crystals is a small scale energy sources. When these crystals

are squeezed, a vibration occurs that produces a very small voltage. These crystals

bend in different directions at different frequencies in which this bending is called

the vibration mode [13].

2.1.5 Lithium-ion Battery

Lithium-ion is a rechargeable battery and is composed of one or more cell.

A cell has a positive electrode that is connected to a battery’s positive terminal.

A cell also has a negative electrode that is connected to the negative terminal.

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Electrolyte is a chemical that is between the negative terminal and positive

terminal of the cell. A battery is said to be a lithium-ion if the movement of ions

is one way when charging and when it moves the opposite way while the battery

is discharging. [14]

Pros:

Light weight

- Lithium-ion batteries have the same weight with the other

rechargeable batteries but lithium-ion batteries are light

weight.

High energy density

- Lithium-ion batteries can store lots of energy in it because

of very high energy density and the battery is made of

light weight lithium and carbon. The lithium in the battery

is also a highly reactive element.

Convenient

- A lithium-ion battery that weighs 1 kilogram can store the

same amount of energy which a 6 kilograms lead-acid

battery can store.

Charging and discharging cycle

- Lithium-ion batteries can handle many charging and

discharging cycles

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Cons:

Short life span

- Lithium-ion batteries that either used or unused have a

short life span of 2 to 3 years from the date of manufacture.

Temperature exposure

- Lithium-ion batteries are very sensitive to high

temperature hence they tend to degrade much faster when

exposed to heat.

Figure 1. Charging and discharging phenomena in Lithium Ion batteries

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This figure shows a lithium-ion batteries while charging and

discharging. A lithium-ion battery is charging when a chemical compound

in the positive electrode gives up a few of the lithium ions, where it travels

to the chemical compound in the negative electrode and remain there. The

battery will store energy to absorb energy. The battery is discharging

when the lithium-ions from the negative electrode will move back across

the electrolyte to the positive electrode to produce energy from the battery

since the electrons flow around the circuit on the opposite way to the ions.

Lithium is deposited on the positive electrode if the ions and electrons will

combine in the positive electrode [14].

2.1.6 Full-Wave Rectifier

There are 4 diodes in the full-wave rectifier circuit. All the diodes are

connected with each other and are forward-biased. Each diode conducts for 180º

of the input cycle. The frequency of the output in a full-wave rectifier is twice the

input frequency [15].

2.1.6.1 Bridge Full Wave Rectifier

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Figure 2. Bridge Full-Wave Rectifier

This figure shows an image of Bridge Full-Wave Rectifier Circuit.

The first diode (D1) and the second diode (D2) are said to conduct current

during the positive half-cycle of the input in the bridge-full wave rectifier

operation. A voltage is developed across the load resistor (RL) that

resembles the positive half of the input cycle. Meanwhile, the remaining

diodes D3 and D4 are reverse-biased. During the negative half-cycle of

the input in the bridge-full wave rectifier operation, the third diode (D3)

and fourth diode (D4) conduct current in the same direction through the

load resistor (RL) as during the positive half-cycle. Meanwhile, the other

diodes which are D1 and D2 are reverse-biased. A full-wave rectified

output voltage appears across the load resistor (RL) as an outcome [15].

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2.1.7 Step – up Chopper

The supply of the step-up chopper is a rectified AC or a battery. The

purpose of a chopper is to improve the DC voltage by converting the fixed DC

voltage into a variable DC voltage. A chopper is a high speed switch that connects

and disconnects the load from the source to attain a variable DV output voltage.

Chopper is also known as DC transformer. A step-up chopper is also known as

boost converter which is used to step-up the voltage from its input side [16].

2.1.8 Compression Springs

Compression springs is an open coil – helical spring which is usually

coiled as a constant – diameter cylinder. When compression force from a load is

applied to the spring, the spring then becomes squeezed. However, with the

design of wires, it tries to go back to its original shape thus pushing the load back

[17].

2.2 Working Theories

2.2.1 Energy Harvesting

Energy Harvesting is the process of acquiring amounts of energy from

one or more natural sources of energy and storing them for future use. Energy

Harvesting plays a vital role in distributing energy to certain applications. It uses

devices which enables to acquire, store, convert and manage efficiently and

effectively the generated energy and supply it in a form that can be used to

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perform a helpful task [18]. Moreover, Energy Harvesting, from natural sources

where an application can be implemented and sources of natural energy is

limitless, is an alternative source of energy to wall plugs and batteries which are

inconvenient and costly. Energy Harvesting includes photovoltaics,

thermovoltaics, piezoelectrics, electrodynamics and many more. Energy

harvesting has its advantages and disadvantages which are enumerated below

[19].

Pros:

Renewable and Abundance

Harvested energy can be manufactured quickly, and

require no other source of energy to operate. One good

example is wind. Wind is a limitless, naturally occurring

phenomenon that is present over the world, and represents

a clean and renewable domestic energy resource.

Cost – effectiveness and continuing improvement of performance

Natural sources of energy costs less since it can be

generated through air, water, vibrations, sun and etc.

Moreover, the performance of the energy harvesting

system can be enhance.

Can be combined into smart integrated energy system

The harvested energy can easily be incorporated with

smart energy systems. Also, different technologies can be

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combined like monitoring systems using Bluetooth,

Zigbee and other technologies.

Cons:

Variable amount of energy generated

There is inconsistency with the amount of energy

generated with natural sources of energy. For an example,

energy generated through footsteps, the number of people

that will step in the energy harvesting devices will never

be constant making the generated energy varying.

2.2.2 Piezoelectricity

Piezoelectricity, also called the piezoelectric effect, is the produce of

electric potential or voltage from the crystals when mechanical stress is applied

through squeezing and deforming the crystal [20]. Piezoelectric effect has a

unique characteristics wherein it is reversible. It can function as a direct

piezoelectric effect where stress is applied to generate electricity. It can also

function as a converse piezoelectric effect where electric field is applied to

generate stress [21].

2.2.2.1 How Piezoelectric Effect Works

The charges in a piezoelectric crystal are normally balanced even

if it is not symmetrically arranged. Before exposing the material to

pressure and stress, the centres of the positive and negative charges of

each molecule concur wherein the charges are reciprocally cancelled.

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Consequently, electrically neutral molecule appears. The piezoelectric

effect happens when the balanced and neutral charge is disturbed through

squeezing the crystals which causes the separation of the positive and

negative charges of the molecules where little dipoles are created.

Subsequently, the facing dipoles inside the material are both cancelled.

The material becomes polarized because of the distributed linked charges.

When the crystal lattice is distorted, the imbalance of the charge creates a

potential difference. This potential difference is also known as the voltage

[22].

2.2.3 Frequency of Oscillation

The oscillation frequency expands as the stiffness of the spring increases.

The frequency of oscillation also expands if the reduction on the mass attached

to the spring is applied [24]. The frequency of oscillation is measure in cycles per

second is mathematically expressed as:

𝑓 = 1

2𝜋√

𝑘

𝑀 Equation 2.2.4

Where: k = spring constant (𝑘𝑔

𝑠2)

M = mass (kg)

2.2.4 Cascaded Operational Amplifier Circuit

The cascaded operational amplifier circuits produce higher voltage gain.

An operational amplifier is in cascade connection if the output of an operational

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amplifier circuit is the input of the next operational amplifier circuit. The total

output gain of the cascaded operational amplifier is the product of the individual

operational amplifier circuits [25]. If there are 3 operational amplifier circuits

given, the overall gain in cascade connection will be mathematically expressed

as:

𝐴 = 𝐴1 𝑥 𝐴2 𝑥 𝐴3 Equation 2.2.5

Where: A1 = stage 1 or 1st gain in the operational amplifier circuit

A2 = stage 2 or 2nd gain in the operational amplifier circuit

A3 = stage 3 or 3rd gain in the operational amplifier circuit

The gain is directly proportional to the voltage output of the operational

amplifier circuit, hence when the gain increases the voltage output also increases.

2.3 Review of Related Works and Studies

2.3.1 Foreign Works and Studies

2.3.1.1 Japan Harnesses Energy from Footsteps

In Japan, special flooring tiles made of rubber sheeting and

stoneware tiles are installed in their ticket turnstiles. These flooring tiles

generates energy from footsteps. The idea behind this is piezoelectricity.

Every steps of the passenger generates a vibration that acts as an energy.

The purpose of rubber sheeting is to absorb the vibrations of the steps

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made by the people who uses the station. This energy will be multiplied

by the number of people who crosses the station. Like in Tokyo station,

the energy will be multiplied over the 400,000 people who crosses the

station in an average day and this energies are sufficient to light up the

electronic signboards, according to East Japan Railway. Takuya Ikeba, a

spokesperson in JR East, said that “We are just testing the system at the

moment to examine its full potential". Same concept is applied in Shibuya

station wherein on an average week, 2.4 million people passes through

this station. Soundenergy Corp. applied the “Energy Generation Floor”.

Yoshiaki Takuya, a planner with Soundenergy Corp. said that "An

average person, weighing 60 kg, will generate only 0.1 watt in the single

second required to take two steps across the tile. But when they are

covering a large area of floor space and thousands of people are stepping

or jumping on them, then we can generate significant amounts of energy."

The generated energies can be stored in a capacitor and can be distributed

to the part of the station including the electrical lighting system and the

ticket gates. It is important to know the generated output energy so that it

can easily determine what type of low energy device it can only energy

up [26].

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Figure 3. Commuters at the Tokyo station walk on a piezoelectric

sheet which generates electricity when pedestrians step on it

This figure shows the application of piezoelectric floor tiles in

Tokyo, Japan. It is used to energy up electrical lighting system and the

ticket gates in train stations. These floor tiles uses a capacitor as a storage.

2.3.1.2 A Shoe-Embedded Piezoelectric Energy Harvester for Wearable

Sensors

An interesting approach for acquiring a clean and sustainable

electrical energy to energy wearable sensors, that are used for health

monitoring, activity recognition, gait analysis and so on, is harvesting

mechanical energy from human locomotion. This study focused on a

piezoelectric energy harvester for the parasitic mechanical energy in shoes

which came from human locomotion. A sandwich structure is designed

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for the harvester to fit and be compatible with the shoes as well as a

consideration for both high performance and excellent durability. An

average output energy of 1mW during a walk at a frequency of roughly

1Hz is obtained from the harvester. Through integrating the harvester with

a energy management circuit, a direct current (DC) energy supply is

created. The DC energy supply is verified by driving a simulated wireless

transmitter that can be activated once every 2 – 3 steps with an active

period lasting 5ms and a mean energy of 50 mW. Hence, this study

illustrates the feasibility of using piezoelectric energy harvesters in

energying wearable sensors. Wearable sensors are becoming smaller and

are frequently used by many which indicates that a need for portable

source of electrical energy is important [27].

Figure 4. A Shoe-Embedded Piezoelectric Energy

Harvester for Wearable Sensors

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24

This figure shows the design of the shoe embedded piezoelectric

energy harvester for wearable sensors. Inside the shoes is the harvester

which contains the energy management circuit and the DC energy supply.

The harvester is mounted inside the shoes with a wearable sensors to

generate electrical energy.

2.3.1.3 Source of Vibration for Crystal Previous Work [28]

2.3.1.3.1 Power Generating Sidewalk

The series connection of piezoelectric crystals are located

under the walking section of the pedestrians on sidewalks and

pavements. Batteries like lithium and capacitors will be charged

by receiving the generated voltage from the piezoelectric crystals

in series. The limitation in the usage of the batteries will depend

on the received generated voltage from the crystals arranged in

series connection.

2.3.1.3.2 Power Generating Boots or Shoes

A groundbreaking design for operating battlefield

equipment where a mechanical energy will be converted into an

electrical energy was proposed by the United States Defense

Advance Research Project Agency (DARPA). The piezoelectric

generators will be inserted in the soldier’s boots. The generated

energy will help to operate or energy up the battlefield equipment.

Although the use of the design is based on good purpose, there is

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25

still an effect in the body of the soldier wearing the energy

generated boots or shoes. As a result, the innovation was

discontinued considering the person wearing the boots

experienced uneasiness or discomfort for exerting additional

energy to generate more energy.

2.3.1.3.3 Gyms and Workplaces

Many gym enthusiasts always help to create vibrations

from the machines and equipment unknowingly. Since there are

effortless number of vibrations that can be accumulated, the

research workers conceptualized an idea to generate energy in an

easy way. At workplaces, there are numerous ways to generate

energy even if the employee is just sitting on a bench or chair. The

energy generated from an employee who is sitting can be

accumulated in a battery for later use by placing the piezoelectric

crystals in the chair. Furthermore, the research for the vibrations

gathered in several parts of a vehicle like foot rests, car seats, and

clutches are being accomplished to make effective use of it.

2.3.1.3.4 Mobile Keypad and Keyboards

Charging in a laptop is an efficient way when there is a

limited electrical outlet but charging with the use of mobile

keypad and keyboards will be more favorable. The piezoelectric

crystals can be placed under the keys of a mobile keypad and

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26

keyboard which will cause vibration with the intention of charging

an electronic device.

2.3.1.3.5 Floor Mats, Tiles and Carpets

Placing a floor mats, tiles and carpets in public places can

collect enormous vibration for the reason that more people are

walking through the piezoelectric materials. A set of piezoelectric

crystals will be placed in the flooring design like floor mats, tiles

and carpets which are regularly placed in public places.

2.3.1.3.6 People Powered Dance Clubs

In western places like Europe, piezoelectric crystals can be

used to energy up the equipment in several nightclubs since the

crystals will be placed beneath the dance floor. Great supply of

voltage will generate from the dance floor from people walking or

dancing through it.

2.3.1.4 Piezoelectric Energy Harvesting

Piezoelectric energy harvesting floor have been implemented at

Rutgers University in Busch Campus Center. The project was installed in

the main highway where a high volume of people’s steps were gathered.

The main goal of the project was to increase the awareness on how to

gather energy from footsteps. The energy generated can supply the

television displays that track the energy harvested. The energy harvested

is about 7 kWh per day using about 20,000 people walking through the

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27

floor tile throughout the day. The proposal of the project gave an option

which are renting the floor tiles and continuing on the expansion to the

other publicly areas on the New Brunswick campus. The estimated cost

of the project are $50,000 for renting the floor tiles and $800,000 for the

full permanent installation. The floor tiles can be installed in top of the

current floor and with the use of an inverter, the generated energy can be

connected to the electrical system of the building and can supply any

electronics like television display. The force exerted on the floor by a

person is approximately about 1 to 1.3x of the body weight. The project

can harvest 50% of the energy. The area covered by the floor tiles is

approximately 4,000 𝑓𝑡2for using 1400 tiles. The total implementation

cost including the installation and maintenance cost is about $800,000. A

50-tile system can be rented because of high installation which are about

$65,000 including the installation and maintenance and it can be renter

over 1-3 year period. A 50-tile system can cover about 18 feet by 6 feet

rectangular area. With the use of this, it can generate 173 Watts which can

supply the monitoring and displaying of the harvested energy [29]. The

monitoring is 5-days in a week and 15 week per semester based on the

table below.

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28

Figure 5. Energy Harvested of Phase 1 and Phase II

This figure shows the table about energy harvested of Phase 1 and

Phase 2 daily, weekly and per semester. The phase I is the rental of the

tiles and the phase II is the installation of the tiles. The phase I consists of

50 piezoelectric floor tiles while the phase II consists of 1400

piezoelectric floor tiles. As shown in the results, the difference in the

generated output energy of phase II to phase I in the semester calculation

is 504.5 kWh.

2.3.2 Local Works and Studies

2.3.2.1 In-Wheel Piezoelectric Generator for Lighting Applications of

Mining Trolleys

Technology has been improving and gradually changing as years

go by. Technology needs electricity for charging purposes and to energy

up an equipment or a device. Piezoelectric transducer is one of the many

ways on how to produce an alternative energy. A piezoelectric transducer

uses a piezoelectric material like crystal. The concept in a piezoelectric

crystal is to convert the mechanical energy caused by the pressure into an

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29

electrical energy. Piezoelectric crystals are applicable especially in

pressure that are heavy in weight. The weight coming from the wheels of

the mining trolley is an ideal example for heavy weight pressure. A

piezoelectric transducer is inserted to the wheels of the mining trolley to

harvest energy since it always carry a very large amount of mining loads.

The generated energy can be used as the energy source to light the mining

trolley. The energy consumption will be reduced from energy line

companies by using an enough alternative source from the piezoelectric

transducer [30].

2.3.2.2 Energy-Harnessing Footwear Using Combined Electromechanical

and Piezoelectric Transducers for Charging Supercapacitors (2009)

Energy harnessing footwear have been popular activating low

energy devices using piezoelectric transducer. These devices acquire

energy from the footsteps of the person using the shoes. This study aims

to provide a new and improved energy harnessing footwear that uses not

only piezoelectric transducers but a combine piezoelectric and

electromechanical transducer which are both integrated in the shoes. The

harvested energy will be stored and will be used to operate low energy

devices such as Light Emitting Diodes and even Cellular Phone. In storing

the harvested energy, an environment friendly component will be used as

the energy storage. This component is a supercapacitor [31].

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Figure 6. Energy Harvesting Shoe

This figure shows the design of the Energy – Harnessing

Footwear. The project used two transducers which are the piezoelectric

and electromechanical transducers. These transducers are located in the

shoe sole.

2.3.2.3 Power Generation for Remote Areas Utilizing Piezoelectric

Transducers Harnessing Wind and Wave Energy (2011)

Piezoelectric transducers are widely used as energy harvesting

material. This study aims to provide simple lighting in remote areas using

piezoelectric transducers as energy harvester. Wind and wave are two of

the most popular sources of ambient energy. These energy are harvested

using a prototype. This prototype are specifically develop to harvest and

store the energy acquired and perform energy regulation techniques with

the use of super capacitors and then transfer the energy to a rechargeable

battery [32].

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Chapter III

Research Methodology

This chapter discusses the methodology used in the study. It explains each section

of the design considerations and hardware specifications of the prototype. The population

and samples are also explained in this chapter. Furthermore, this chapter shows the ideal

set-up of the Piezoelectric Puzzle Floor Mat. Succeeding section explains the conducted

procedure and analysis to examine the appropriate output energy. This study also

illustrates particular diagrams to expound how the output energy will be attained which

is the main objective of this project.

3.1 Conceptual Framework

Figure 7. Conceptual Framework

This figure shows the conceptual framework of the system. The input in the

project is the footsteps. Footsteps are form of mechanical energy. Vibrations are the

wasted energy that comes from the human footsteps. An average person can take 3,000-

5,000 steps a day [2]. These footsteps came from only one person, it means that if there

OUTPUT PROCESS INPUT

Footsteps

Vibration

Converts the

vibrations to DC

voltage

Usable DC

voltage

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are many people walking, there are also a higher calculation of the footsteps that can be

collected per day. The project must be placed in a public place to acquire many footsteps.

The generated output energy will be higher if there are many footsteps walking through

the project. The main process of the project is to convert the vibrations produced by the

footsteps into DC voltage. The output in this project is in the form of usable DC voltage

which can be the supply voltage for some low energy applications.

3.2 Block Diagram

Figure 8. Block Diagram

Mat Surface

Piezoelectric circuit

Full-Wave Rectifier

Step-Up Chopper

Lithium-ion Battery

Wired monitoring

using Energy meter

or V/I meter

Load

Footsteps

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This figure shows the block diagram of the system. The human footsteps will

make contact and apply pressure to the mat surface that will produce vibrations. The

piezoelectric circuit converts the vibrations caused by the footstep into an AC voltage.

The output AC voltage is converted to DC voltage using a full-wave bridge rectifier. The

fixed DC output voltage of the rectifier will be converted into a variable DC voltage with

the use of a step-up chopper and will be stored in a Lithium-ion battery. The generated

voltage can be applied to a load but depending on the kind of load it can only supply. The

output energy per step of the project is monitored by using an energy or V/I meter.

3.3 Schematic Diagram

Figure 9. Circuit Diagram of the System

Where:

X1 = 25 piezoelectric crystals connected in series

D1, D2, D3, D4 = 1N4001

C1 = Electrolytic capacitors, 470µF 25V

B1 = Lithium-ion battery, 3.7 VDC

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This figure shows the circuit diagram of the project. This also shows the

interconnection of the Full-Wave Bridge Rectifier, Step-Up Chopper, Lithium-ion

Battery, and the Full-Wave Bridge Inverter. The voltage source of the circuit is AC

voltage produced by the 25 Piezoelectric Crystals connected in series. The generated

energy will be consumed by the load if there is a load.

3.3.1 Full-Wave Bridge Rectifier

Figure 10. Full-Wave Bridge Rectifier

This figure shows the Full-Wave Bridge Rectifier circuit diagram. The

Full-Wave bridge rectifier converts the AC voltage source that produces by the

25 Piezoelectric Crystals connected in series into a pulsating DC. The capacitor

acts as a smoothing capacitor that smooth out the pulsating DC produced by the

Full-Wave Bridge Rectifier and creates ripples.

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3.3.2 Step-Up Chopper (DC/DC converter)

A Chopper is a kind of a DC/DC converter and its energy source could be

a rectified A.C. or a battery. The main function of a Chopper is to convert a fixed

DC source into a variable DC voltage. In the project, the input voltage of step-up

chopper is the rectified output voltage of the Full-Wave Bridge Rectifier.

3.3.3 Lithium-ion Battery

Figure 11. Lithium-ion Battery

This figure shows the Lithium-ion Battery which purpose is storing of the

DC voltage output from the step-up chopper.

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Table 1. Specifications of Lithium-ion Battery

This table shows the specifications of Lithium-ion Battery. The output voltage of

Lithium-ion battery is 3.7VDC

3.4 PCB Layout

Figure 12. PCB Layout

This figure shows the PCB layout of the circuit diagram of the system and the

connection of each components in the PCB.

Model GEB5650122

Voltage Output 3.7V DC

Current Capacity 4000mAh

Charging Voltage 4.25V 500mAh

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3.5 Flow Chart of Process

Start

Wait for the person

to finish stepping

on the floor mat

Footsteps

Is the person

finish

stepping on

the floor

mat?

Vibrations produced will be

converted to AC voltage with

the use of piezoelectric circuit

AC will be converted to DC

using a full-wave bridge rectifier

Fixed DC voltage to variable DC

voltage using a Step-up Chopper

A

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Figure 13. System Flowchart

This figure shows the system flowchart of the system. The system will start when

the footsteps have made contact to the surface of the floor mat. The system will ask if the

person that made contact to the floor mats’ surface is finished stepping on the floor mat.

The system will wait for the person to finish stepping in the floor mat if the answer is

No, it will return to the question. The system will create a loop until the question is

satisfied. The vibrations produced will be converted to AC voltage with the use of

piezoelectric circuit if the answer is YES. The AC output voltage from the piezoelectric

A

DC output stored in a Lithium-ion battery

DC voltage

Monitor using energy or

V/I meter

Is there

a load?

The load will consume the DC

electrical energy stored in the

Lithium-ion battery

End

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circuit will be converted into a DC voltage with the use of a full-wave bridge rectifier.

The fixed DC voltage output of the rectifier will be converted to variable DC voltage

with the use of a step-up Chopper and will be stored to a Lithium-ion battery for later

use. The system will ask if there is a load connected to the circuit. The load will consume

the output DC electrical energy if there is a load connected to the circuit. The energy or

V/I meter are the device that will be used to monitor the energy of the mat per step. The

system will standby if the floor mat stops to oscillate.

3.6 Test Population

Through the data gathered from Computer Services Office (CSO), the average

number of students that enter the building of FEU – Institute of Technology per day is

5,780 from November 9 to 14, 2015. The average number of students that leaves the

school premises is the same as the average number of students that enter. The researchers

use the exit as the location of the device so most of the students will be able to step on

the mat and to avoid getting wet of the Piezoelectric Puzzle Floor Mat. Due to the

inconsistency of implementing of tapping the I.D., the researchers chose the date of

November 9-14 of 2015 because of the strict implementation of tapping the I.D. in the

entrance.

3.7 Treatment of Data

3.7.1 Calculations for the number of trials

The researchers set a standard error tolerance level of 5%. The researchers

the error tolerance of 5% because it is the department standard and usually used

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in thesis. The researchers will determine the number of samples/trials needed for

the project using the Slovin’s formula:

𝑛 = 𝑁

1+𝑁𝑒2 Equation 3.7.1

Where: n = number of samples/trials

N = total population

e = error tolerance

Computing for the number of samples using Slovin’s formula, N = 5,780

n = 5,780

1+(5,780)(0.05)2 = 374.11 ≈ 374 trials

Thus, the number of trials needed to attain the appropriate energy output

of the Piezoelectric Puzzle Floor Mat through continuous testing is 374.

3.7.2 Calculation for the Tolerance

Tolerance = Average energy output − Energy output

Average energy output x 100%

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3.8 Testing Procedure

1. Assemble and place the Piezoelectric Puzzle Floor Mats on the floor

2. Be sure that the battery is fully discharge at every first trial

3. Have only one person weighing exactly 63kg to perform the testing in

order to know whether the mat acquires a constant value of energy for

every trial and to have a constant force applied to the mat. The person

must step on the mat in his natural/normal way of walking

4. Measure the energy per step acquired by the system using an energy

or V/I meter for 374 people a day for 16 days in order to test also if

the floor mat can still be functional when it is use every day and to

assume that the number of average students that enter to the school

premises stepped on the floor mat

days = ave. students

number of trials=

5,780

374= 15.45 ≈ 16 days

3.9 Proposed Table for Test Results

Table 2. Table for test results

Day Number

Trials Energy Output per step

(J/step)

Tolerance %

1

2

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3

4

5

.

.

.

374

Ave. Ave.

Average energy output for 16 days: ______________

Average percentage tolerance for 16 days: ________________

The table above shows the number of trials, the energy output in each trial, the

percentage tolerance, if the battery is fully charged, the average energy output and the

average percentage tolerance. The researchers will perform the testing for 16 days,

therefore it will have 16 tables for each day

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3.10 Proposed Project

3.10.1 Ideal Set up

Figure 14. Ideal Set-up: A man stepping on the floor mat

This figure shows the ideal set up of the device where a man steps onto

the mat. Thus, creating vibrations that will produce mechanical energy which is

then converted to electrical energy.

3.10.2. Design Considerations of Puzzle Floor Mat

Figure 15. Dimensions of the Puzzle Floor Mat

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This figure shows the dimensions of the Piezoelectric Energy Harvesting floor

mat which is a 20” by 20” by 3”. The dimension of the mat was in a square shape so that

the force exerted on the Puzzle Floor mat is equally distributed.

Figure 16. Top View of the Puzzle Floor Mat

This figure shows the top view of the Puzzle Floor Mat which consist of male

jack whose purpose is to connect the output energy of the mat to the input of the other

mat and female jack whose purpose is to receive the output of the other mat and connect

it to the input of the mat.

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Figure 17. Inner Part of the Puzzle Floor Mat

This figure shows the inner part of the Puzzle Floor Mat where it consists of

Piezoelectric Crystals, wires, and springs. The Piezoelectric Crystals are connected in

series to have a higher electrical energy. The length of the springs is 1”. The maximum

weight it can handle is 36,993kg. Therefore, the capacity of the floor mat can still sustain

the weight of any student as long as it does not exceed 36,993kg.

To compute for the maximum weight capacity of the mat, the researchers used

the formula of stress. Stress is ratio of the force to the cross-sectional area and tends to

compress or shorten the material [33]. The yield strength/stress for steel is 250Mpa and

the area of the project’ supports is 1.5” by 1.5”.

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ℴ = Force

Area

250MPa = (max 𝑤𝑒𝑖𝑔ℎ𝑡 𝑖𝑛 kg)(9.81

ms2)

(1.5inches)2 (2.54𝑐𝑚1𝑖𝑛𝑐ℎ

)2

(1𝑚

100𝑐𝑚)2

Max weight in kg = 36,993.11927 kg ≈ 36,993kg

Table 3. Specifications of Smaller Spring

This table shows the specifications of the smaller springs. The spring’s model,

outside diameter, free-length, approx. load and solid height, solid height, maximun

deflection, and the spring rate/constant are shown in the table. The springs should be

sturdy enough so that when a person step on the mat, it will not be deformed.

Lee Stock number (model) LHP 098G 04S

Outside diameter 0.48” or 12.19mm

Free Length 1” or 25.40mm

Approx. Load at Solid Height 122.18 lbs or 55.421 kg

Solid Height 0.715” or 18.16mm

Max. deflection 0.285” or 7.24mm x (0.80)

Spring rate/constant 429.96 lb/in or 7.678 kg/mm

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Table 4. Specifications of the Bigger Springs as a support

Lee Stock number (model) LHP 130J 03S

Outside diameter 0.72” or 18.29mm

Free Length 1” or 25.40mm

Approx. Load at Solid Height 165.10 lbs or 74.889 kg

Solid Height 0.705” or9mm

Max. deflection 0.295” or 7.51 mm x (0.82)

Spring rate/constant 559.80 lb/in or 9.997 kg/mm

This table shows the specifications of the bigger springs as a support. The spring’s

model, oustdie diameter, free-length, approx. load and solid height, solid height,

maximun deflection, and the spring rate/constant are shown in the table. The springs

should be sturdy enough so that when a person step on the mat, it will not be deformed.

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(a.)

(b.)

Figure 18. Comparison of design with respect to vibrations

This figure shows the comparison of design of existing study with the researchers’

study with respect to vibrations. Figure a shows the design of an existing study of

Piezoelectric floor tile which has four springs as a support to the floor tile. While figure

b shows the design of current study which has a total of 29 springs as a support to the

floor mat. Figure b can produce larger and longer vibrations since it has the more number

of springs. Moreover, the location of the spring of figure b is just below the floor mat

unlike figure a. Thus, the effect of the steps is directly to the springs. The more number

of springs, the less its tendency of going sideways.

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[4

0]

"Star Trek," startrek.com, 2015. [Online]. Available: http://stattrek.com/chi-square-

test/independence.aspx?Tutorial=AP.

[4

1]

M. S. N. N. G. Monika Jain, ""VIDYUT Generation via Walking: Analysis"," International

Journal of Engineering Sciences and Resaerch Technology , Feb 2013.

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APPENDIX A

Chi-Square Critical Values Table

Degrees of

Freedom

Probability of Exceeding the Critical Value

0.10 0.05 0.025 0.01

1 2.706 3.841 5.024 6.635

2 4.605 5.991 7.378 9.210

3 6.251 7.815 9.348 11.345

4 7.779 9.488 11.143 13.277

5 9.236 11.070 12.833 15.086

6 10.645 12.592 14.449 16.812

7 12.017 14.067 16.013 18.475

8 13.362 15.507 17.535 20.090

9 14.684 16.919 19.023 21.666

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10 15.987 18.307 20.483 23.209

11 17.275 19.675 21.920 24.725

12 18.549 21.026 23.337 26.217

13 19.812 22.362 24.736 27.688

14 21.064 23.685 26.119 29.141

15 22.307 24.996 27.488 30.578

16 23.542 26.296 28.845 32.

17 24.769 27.587 30.191 33.409

18 25.989 28.869 31.526 34.805

19 27.204 30.144 32.852 36.191

20 28.412 31.41 34.17 37.566

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APPENDIX B

Bill of Materials

The tabulated estimation cost of the materials that are needed for the construction

of the project are listed below:

No. Materials Price Quantity Total Price

1 Piezoelectric

Buzzer/Transducer 50.00 25 1250.0

2 Puzzle Rubber Sheets

(20in x 20in x 3in) 500.00 10 5,000.00

3 Stainless Steel

(15in x 1in x 1in) 2,500.00 1 2,500.00

4 Vinyl Tile 80.00 8 640.00

5

Banana Jacks (Female) and

Plug (Male)

150.00

150.00

4 pairs (8 pieces)

Banana Jacks

4 pairs (8 pieces)

Banana Plugs

1,200.00

6 Small Compression Spring 75.00/pack 100 150.00

7 Big Compression Spring 80.00/pack 20 80.00

8 Diodes

(1N4001) 10.00 20 200.00

9 Capacitors

(470uF, 25V) 6.00 2 12.00

10 Chopper 1,000.00 1 1,000.00

11 Energy meter 5,000.00 1 5,000.00

12 Lithium – ion Battery

(3.7V) 575.00 1 575.00

13 PCB and Developer 90.00 4 360.00

14 Ferric Chloride 40 1 40.00

TOTAL 18,007.00

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APPENDIX C

Gantt Chart

This table provides the chart illustration of the researcher’s Project Study 1

schedule which enables the researchers to coordinate and track specific activities and

tasks.

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APPENDIX D

Average Weight of Students in FEU-Institute of Technology

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APPENDIX E

Data of Average Students that Entered the School Premises

Date Number of Students that

Entered the School

Premises

2015-08-25 744

2015-08-26 6,075

2015-08-28 6,288

2015-08-29 4,834

2015-09-01 5,715

2015-09-02 4,352

2015-09-03 5,484

2015-09-04 5,412

2015-09-05 4,066

2015-09-07 4,882

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2015-09-08 5,335

2015-09-09 4,620

2015-09-10 4,673

2015-09-11 2,445

2015-09-12 3,535

2015-09-14 4,875

2015-09-15 4,891

2015-09-16 4,016

2015-09-17 4,038

2015-09-18 3,948

2015-09-19 2,466

2015-09-21 3,628

2015-09-22 3,180

2015-09-23 3,614

2015-09-24 3,587

2015-09-26 2,750

2015-09-28 3,704

2015-09-29 2,389

2015-09-30 1,556

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2015-09-30 1,556

2015-10-01 3,215

2015-10-03 2828

2015-10-05 2,320

2015-10-06 2,377

2015-10-07 1,684

2015-10-08 1,789

2015-10-09 1,691

2015-10-10 1,565

2015-10-12 1,401

2015-10-13 1,040

2015-10-14 522

2015-10-15 837

2015-10-16 4,030

2015-10-17 4,073

2015-10-20 4,256

2015-10-21 3,502

2015-10-22 2,080

2015-10-23 3,794

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2015-10-24 345

2015-10-26 1,334

2015-10-27 3,987

2015-10-28 2,793

2015-10-29 1,656

2015-10-30 1,678

2015-11-02 5,816

2015-11-03 5,953

2015-11-04 6,445

2015-11-05 8,109

2015-11-06 7,158

2015-11-07 5,123

2015-11-09 7,103

2015-11-10 6,698

2015-11-11 5,430

2015-11-12 6,048

2015-11-13 5,672

2015-11-14 3,729

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APPENDIX F

CONSULTATION SHEET

Project Study 1

Members:

CAPATI, Aubrey Sharmaine M. Engr. Luigi Carlo M. De Jesus

MAGLUYAN, Pamela Kim Donnelle G. Adviser

POSTRE, Raul Christian M.

DATE TIME ACTIVITY SIGNATURE

08 – 20 – 15 18:00 – 19:00 Chapter __ : Consultation

08 – 24 – 15 14:30 – 15:00 Chapter __ : Consultation

08 – 27 – 15 16:00 – 16:30 Chapter __ : Consultation

09 – 02 – 15 13:30 – 14:00 Chapter __ : Consultation

09 – 06 – 15 12:30 – 14:00 Chapter __ : Consultation

09 – 07 – 15 16:10 – 17:35 Chapter __ : Consultation

09 – 10 – 15 15:40 – 16:00 Chapter __ : Consultation

09 – 11 – 15 16:40 – 16:55 Chapter __ : Consultation

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09 – 16 – 15 13:45 – 15:00 Chapter __ : Consultation

09 – 21 – 15 13:10 – 13:30 Chapter __ : Consultation

09 – 22 – 15 13:50 – 14:30 Chapter __ : Consultation

09 – 24 – 15 13:10 – 13:50 Chapter __ : Consultation

09 – 30 – 15 10:42 – 11:05 Chapter __ : Consultation

10 – 03 – 15 12:40 – 13:15 Chapter __ : Consultation

10 – 08 – 15 13:40 – 14:35 Chapter __ : Consultation

10 – 12 – 15 13:15 – 14:10 Chapter __ : Consultation