final year embedded systems projects in chennai

http://www.embeddedinnovationlab.com
ABSTRACT
Final year embedded systems projects in chennai . Nowadays energy and
power are the one of the basic necessities regarding this modern world. As the
demand of energy is increasing day by day, so the ultimate solution to deal with
these sorts of problems is just to implement the renewable sources of energy. But
these renewable energy sources must have to be adopted in practical manner by
keeping an eye on all aspects regarding the research work. Final year ece projects
in chennai .So then these techniques should be applied in order to get the desired
output. In case of our project we have used the technique of power generation
through footsteps as a source of renewable energy that we can obtained while
walking on to the certain arrangements like footpaths, stairs, plate forms and these
systems can be install elsewhere specially in the dense populated areas.final year
eee projects in chennai .
The basic working principle of our project ‘footstep power generation system’
is based on the piezoelectric sensor. Final year mechanical projects in
chennai.So in order to implement this foot step power generation system we adjust
the wooden plates above and below the sensors and moveable springs, when we
walk on the mat than automatically force is applied and as a result magnet fixed
under the top wooden sheet and moves into the cavity. As this cavity is fixed at
bottom wooden sheet of mat so between the moveable springs adjusted between
the top and bottom sheets.final year engineering projects in chennai
As a result of completing the above procedure or technique we made
ourselves able to design such compatible system through which we could run our
home appliances through AC output. As our main purpose was to charge the
battery through DC output and then by inverting it into AC for normal common
usage.
Thus as a result we have concluded that these types of designs and techniques
of power generating systems are very useful and handy in order to match the
supply and demand of energy globally as well.

CHEPTER 1
INTRODUCTION
Energy surrounds us in all aspects of life, it’s up to us weather we use it
constructively for the benefit of mankind or
we use it destructively to harm others. Alternative energy resources are not based
on fossils fuels or atom distribution.
The alternatives are
 Solar energy
 Wind power
 Geothermal
 Hydroelectric
 Nuclear
We are introducing a new way to overcome the increasing demand of energy.
We are utilizing human force and we named it FSGS (Foot Step Generating
System). Final year eee projects in bangalore
1.1 Motivation
Man is hunter of energy from the starting of human being. First he started in
the form of food i.e. to get energy from animals and plants. Then man started
cultivation of land to get food and he gave a new trend to energy by training
animals for his help in doing job. Demand is always increasing day by day and
year by year so he started to use wind for driving ships in the sea and falling water
to turn water wheel. Final year projects in chennai
1.1.1 Defining the problem

In Pakistan the demand is more than the daily energy produced so we are
facing power-cut after approximate 1 hour and industries are in hell these days.
People uses rechargeable batteries (UPS) or diesel/petrol engine to fulfill their
demands. The use of stand by generator is common in industries and large offices.
1.2 Objective of project
“Final year mechanical engineering projects in chennai .” Our aim is to
produce energy by a source that has no negative effect on environment and its
output can be used to overcome the crises in Pakistan.
1.3 Principle of project
The principle of project has few steps in it regarding which generate power
through footsteps using piezoelectric sensor. We start with the proper arrangement
of electrical components and equipment which transforms the mechanical energy
in to electrical energy.
The second part of piezoelectric sensor is mechanical part, which involves
spring connection to piezo, so by movement of footsteps up and down spring is
giving vibration to piezo which generate electrical power and this power will be in
the form of electric current. And these two arrangements electrical and mechanical
combined together which transforms mechanical energy to electrical energy.
When producing power with footsteps on piezo there is some load placed at the
end which used power, then power stored in battery is decreased so more footsteps
on spring which vibrate the step and due to vibration force power generated.
“Final year engineering projects in bangalore. “ Voltages which produced
from piezoelectric sensor is A.C voltages while we need D.C voltages to store in
the battery, so for this purpose rectifier circuit is used. In rectifier circuit we can
used either half wave rectifier or full wave rectifier. Our concern is with full wave

rectifier because it gives full value. So now A.C voltages are converted in to D.C
voltages. Now by placing next the battery charger circuit and battery, battery
charger circuit is charging the battery and this D.C voltages is stored in the lead
acid battery of 12 volt. Final year be projects in chennai.
Lead acid battery of 12 volt which is charged is now further connected to the
inverter. As we have D.C voltages stored in the battery but we need A.C voltages
because mostly load need A.C voltages so by using the inverter circuit which is
such designed that it inverts the voltages from battery which is 12 volt D.C to 220
volt A.C voltages.final year vlsi projects in chennai and bangalore
So this A.C voltage is used in different appliances such as for charging the
laptop battery and also to charge the handset, it can also be used to lightening up
the energy savor. If we need more power from this technique then used more steps
for more electric current, final year ece projects in chennai.and also increase the
connection of piezoelectric sensor which is connected parallel and series
combination and by vibrating with the help of footsteps gives electrical power
which is in the form of electric current. Then ability of battery and inverter should
be increased, battery should be of high current and voltages and inverter is such
designed that it convert that electrical power to A.C voltages and also no loss in it,
then output power will be increased and can be used more electrical appliances and
also can be used such appliances which need more electric current..final year ece
projects in bangalore.
1.4 Renewable energy resources
Due to global warming and worldwide heating now globe is stirring to
renewable energy resources. Other alternative resources which are using for
generating electrical power are very expensive and either their units are shut down
in Pakistan. Maintenance of already existing energy sources caused huge amount

of cost, so much cost is due to the heavy machinery involving in it which need
maintenance and also the labor and engineering work. These existing energy
sources are also harmful for humans, the rays from nuclear generator caused cancer
to the nearer city, and final year mechanical projects in bangaore.hydroelectric
projects caused flood to cities and also damaged the fields. So due to these
problems globe is stirring to renewable energy resources which are fairly low cost,
efficient while using, reliable and caused no uneasiness to human nature. The
renewable energy resources such as solar panels, wind turbine, geo thermal, bio
gas etc. they all used natural things for generating electrical power so the danger to
human will be no more as in the case of nuclear energy. The maintenance costs of
these plants are very low. These plants do not contain any heavy machinery for
generating electrical power. So when these plants are out of working or some error
in it and it needs maintenance then the maintenance cost is not so much high and
also it don’t need labor works because it is not involving any heavy machinery in it
and it only requires engineering work in it. Final year eee projects in chennai.So
that’s why our project is of renewable energy resources and we generate electrical
power by footsteps and it is fairly low cost and efficient technique.
1.5 Energy crises in Pakistan
Power is the mainly central basis in support of financial increase of a state.
There will be main power crises that must look Pakistan in future for next two to
three years in power, oil and natural gas. Now Pakistan is suffering energy crises in
all most every field. So that’s why Pakistan gross domestic product is low because
due to industrial shut down, shut down of local factories as well domestic factories.
Today mostly everything every business is depended upon power. Now power is
the backbone of every country and in Pakistan which is also nuclear country is
suffering too much problem of energy from last five to seven years.

Energy crises in Pakistan have a lot of reasons. Recession is one of them
Pakistan is suffering recession and economic crises from last seven years. Inflation
is increased to its higher value, so that’s why investment from foreigner is
decreased to great extent. Due to all these problems Pakistan is suffering the
energy crises. Final year eee projects in bangalore.
The other reason of short fall is that money not giving to independent power
producers. So these independent power producers not deliver full power and also
they mostly shut down their units. And also money is no giving to oil delivers and
oil producers. Money also doesn’t give to Pakistan state oil which delivers oil to
power plants. When they don’t have money then they don’t deliver oil and oil is
necessary for power plant so short fall increases. Pakistan has also loan on it so
they don’t get any loan from World Bank. So that’s why energy is not producing in
the plants and they shut down their units and our economic growth is decreased. If
they don’t have power industrial and domestic structure will be finished.
Further reason of energy crises in Pakistan are not constructed the new
dams and new power plants units. “Final year mechanical projects in chennai.”
Kala bagh dam is constructed in past not completely but the feasibility report of
this dam is completed and equipment for this dam is also purchased and also it
fulfills all our electricity needs but due to political reasons this dam is not started
and its work is stopped so that’s why short fall increases day by day. Huge amount
of money is also wasted on this dam while there is no output also caused a lot of
problems. So if we are not constructed new dams and wasting the money then the
short fall increases and energy crises also increases to great extent. So construct
new dams to fulfill the need of energy.
The other reason for energy crises in Pakistan is not maintaining the
already build power plants once the power plant is damaged due to any reason then

that unit will be completely shut down. And burden on other units increase which
in turns increase the short fall. Also the staffs don’t take care of power plants. So
this is also very bad aspect of energy crises in Pakistan. This can be reduced by
taking proper caring of power plants and maintained at right time. So in this case
short fall can be reduced. final year vlsi projects in chennai.
Due to corruption while running the power plants is also increase the
energy crises. As the corruption ratio in Pakistan is very high especially in
government sectors. So due to bad management and corrupt staff as well as
illegible officers working in power plants caused energy crises in Pakistan. Miss
management also causes problem while running the power plants. If power plant
unit is not turn off and turn on completely at specific time will increased energy
crises and short fall will be increased and this all happens in Pakistan.final year
engineering projects in chennai
Pakistan is also have very high demand of gas, industries and factories needs gas to
great extent but in Pakistan availability of gas is very low, some of the power plant
unit also works on gas but of not continuous supply of gas some of unit shut down
so that’s why short fall increases and energy crises also increases.
Solution: above mention we write all crises in Pakistan about energy so the
economy is low so we should find a way to generate electricity which is cheapest
and efficient. If we install our system to 300ft and 2500 men walk through that
area four times in a day then we can produce 0.7MegaWatt in a day. If we need
more energy area should increased.
1.6 Footstep power generation resources
There are various resources of power generation through which we can
generate the power with footsteps. It is unique and different type of power

generation system it requires a technology and huge amount of research work that
is why this type of generation system is mostly in use of developed countries.
This type of power generation can be done through various techniques and
methods like piezoelectric sensors, through mechanical arrangement like fly wheel
and gear wheel, pedal and springs type arrangement, staircase energy generating
system by rotating the generator, then also by implementing the faraday’s law of
electromagnetic induction by moving magnet into the coil through spring system.
Our project is based on piezoelectric sensors we have designed structure
like mathere large number of sensors are placed in series and parallel connection.
The springs are placed between the sheets of sensors and springs have enough
tensile strength that they can bear the weight. . This type of footsteps power
generation system are eligible to be installed in crowded places and rural areas
cities in the places like railway stations, airports, footpaths where there is a rush of
pedestrians.
CHAPTER 2
LITERATURE SURVEY
2.1 Purpose
There are few methods to generate electrical energy from footsteps. Gear
wheel and fly wheel are techniques to generate electrical power. This method also
work on this principle and in it mechanical part are used because it is placed on
where the number of peoples are more and energy produced by their movement on
the floor.
Power would generated by footsteps of crowd on the floor. Piezo plate scheme is
located beneath the floor then the then there will be sheet covering the piezo plate
and also spring will be there for vibration force on piezo. The piezo plate will be in
chunks in the floor. This plate will generate power in the type of electric current.

The power produced by pedestrians can also be used as additional features such as
to lightning up street light or the light that used at that place for pedestrians. So the
pedestrians should give credit the energy which produced by their movement.
2.2 Literature Analysis
To generate electrical power using footsteps one step will be enough at this
level to produced electrical energy.
As studied few methods from which power is generated. Following are the
steps of fly and gear wheel method. As piezo plate is also involves these steps.
First step is by proper arrangement of electrical components and equipment
which transforms the mechanical energy in to electrical energy.
After the arrangement of electrical system which transforms mechanical
energy to electrical energy, then the spring is attached with sheet to piezo so the
spring arrangement is done, spring vibrate the piezo.
When load using the power then this spring is used to vibrate the step by
force then power is produced. Final year ece projects in chennai.
Then the voltage that produced through steps is rectified and after battery
charger circuit this D.C voltage is stored in the lead acid battery of 12 volt.
This lead acid battery is further attached to the inverter. The invert is such
designed that it inverts the voltage from battery which is 12 volt D.C to 230 volt
A.C.
So this A.C voltage is used in different appliances such as for charging the
laptop battery and also to charge the handset, final year embedded system
projects in chennai. it can also be used to lightening up the energy savor. If we
need more power from this technique then used more steps for more electric
current and also then ability of battery and inverter should be increased then output
power will be increased.
2.2.1 Uses
The electrical power that is produced by footsteps is mostly suitable at
where the numbers of pedestrians are more and also crowdie places.

The places such as:
Universities
Bus Stands
Arrival and departure of passengers at air ports
Shopping Mall
Food streets
Footpath
Markets
Final year ece projects in bangalore. Pedestrian bridges this is the finest
purpose of generating power by footsteps. Its cost is very low. This power then
used for lights on bridge, street light, also light used for traffic purpose.
Public places final year mechanical projects in bangalore
These all are the places where just planting of system cost matter and as this
cost is fairly low so unlimited input and high power will produce.
2.2.2 Aspects
Main feature of footstep power generation through piezoelectric is that
electrical power produced by transforming mechanical energy to electrical energy
of the movement of people on the floor where piezo plate is placed.
A further aspect of piezoelectric power generation system is that it is safe
and secure to use, still this system is working, make no problem and no discomfort
for the people, and it is totally risk free method.final year vlsi projects in
bangalore
Footstep power generation through piezoelectric have mechanical part as
well as electrical part but this system has not so many losses, also this system is not
damaged completely by any sort of thing and this system has very low cost of
equipments and components so if system is damaged then the cost of the system is
very low, this is also the feature of footstep power generating system through

piezoelectric. This system also has the capability to store the electrical power in
storage battery.
This system generate electricity to lightening up the lights used in streets,
also for traffic purpose, sign boards of roads, the power which will be left behind is
given to national grid for electricity purpose.final year projects in chennai
This system footstep power generating system through footstep is cheap,
efficient and reliable method.
upcoming extent
Now globe is stirring to the renewable resources due to the worldwide
heating so this project footstep power generation through piezoelectric has a vast
extent. Other renewable resources are also used such as solar sterling plant, bio
gas, wind turbine etc. but if contrast with footstep power generation through
piezoelectric sensor is fairly low cost means to say inexpensive, useful, efficient
and reliable than these renewable resources.
2.3 Block diagram

Figure 2.1 Footstep general block diagram
2.3.1 Components / parts
Piezoelectric sensor mat
Battery charger circuit
Lead Acid Battery
Inverter
Load
2.3.1.1 Timber Pieces

We made timber pieces for footsteps on which force will apply. In footstep
power generation through piezoelectric sensor project designing a plate consist of
piezo which is connected in series and parallel arrangement. There are three timber
pieces each has width and length of 1ft. Final year eee projects in chennai
2.3.1.2 Springs
Spring is used on the top of each piezo sensor, while applying force on
spring it gives vibration to piezo and power produced in the form of electric
current.
3.0 THEORETICAL DESCRIPTION
3.1 Introduction
We mostly relay on our hydro source which is not as much enough as we
required or maybe our country is not utilizing it in a good manner so it is primary
need of the country that power may produce by any source so that they can fulfill
the need of the people and industries as well because without providing power to
industries we are not able to make people happy. To start new large projects first
we need lot of money i.e. nuclear power, hydro need much more money. Lot of
energy is wasted daily coming from some natural sources. The idea of this project
live behind that human walking is a natural process which can’t be stopped, so why
we waste it knowing the fact that this energy is useful for producing energy. We
can use it in highly populated country like china but also in our country in which
energy crises are headline of the day. We are erasing this problem on cheap and
small projects implementation.
FOOT STEP POWER GENERATION USING PIEZOELECTRIC
MATERIAL
FootStep Power Generation Using Piezoelectric Material

In this project the conversion of the force energy in to electrical energy.
The control mechanism carries the piezoelectric sensor, A.C ripples neutralizer,
unidirectional current controller and 12V, 1.3Amp lead acid dc rechargeable
battery and an inverter is used to drive AC/DC loads. The battery is connected to
the inverter. This inverter is used to convert the 12 Volt D.C to the 230 Volt A.C.
This 230 Volt A.C voltage is used to activate the loads. We are using conventional
battery charging unit also for giving supply to the circuitry. Here we are using
16X2 LCD to display the voltage values of the rechargeable battery using
AT89S52.
"An average person, weighing 60 kg, will generate only 0.1 watt in the
single second required to take two steps across the tile," said Yoshiaki Takuya, a
planner with Sound power Corp. "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 power."Stored in capacitors, the power can be
channeled to energy-hungry parts of the station, he said, including the electrical
lighting system and the ticket gates. Final year eee projects in chennai
.
If by the grace of ALLAH we become successful in the project then human
energy that is wasted all the day in all life could be made useful for mankind. The
best implementation of this idea will be at railway stations, crowded malls,
universities, colleges, schools, government offices and areas with large crowd
daily.final year engineering projects in chennai
In this project we are producing electricity by simply walking or running or
by vehicles which is non conventional source of energy and at this stage non-
conventional energy is very needed for our country. We can make it possible
through mechanical design or through electrically. We are using piezo electric
sensor to do it. Some researchers also win this game by coil and magnet
arrangement but we are not discussing it because it not our job, it is totally
mechanically. In this some people make stair-case arrangement.
This project converts the vibration energy in to electrical energy. The
control mechanism carries the piezo electric sensor, current controller and 12V,
1.2Amp lead acid dc rechargeable battery and an inverter is used to drive AC/DC
loads. The battery is connected to the inverter. This inverter is used to convert the

12 Volt D.C to the 220 Volt A.C. This 220 Volt A.C voltage is used to activate the
loads. We are using conventional battery charging unit also for giving supply to the
circuitry.
3.2 Sensor
A sensor is a device that measures a physical quantity and converts it into
waveform which can be read by an observer. Like mercury which shows the
temperature of the body by the liquid expansion. Sensors are calibrated by a scale
which is easy for observer.
3.3 Piezo Electric Sensors
A device which measures the force, pressure, strain and vibration and
converts it into electrical signals is known as piezo electric sensor. These materials
exhibit a property known as piezo electric effect in which force or vibration is
produced an electric field is created which causes a potential difference across
these materials and hence current start flowing through it.
Final year embedded system projects in chennai Piezoelectricity is from
Greek word which means pressure electricity. There are many crystals like Lead
Zirconate Titanate that produce electric charges when pressure is applied on them
or they vibrate when subjected to potential difference. The amount of charges
depends upon the frequency of vibration. AC voltage vibrates the piezo electric
material at the same frequency at which we are providing AC.
Quartz is the best example of piezo material. The materials with ABO3
have the strong property of piezo electricity, where ‘A’ denotes large divalent ion
(lead) while ‘B’ is for small tetravalent ion (titanium).
Piezoelectric technology rises due to set of inherent advantages i.e.
 High modulus of elasticity ( N/)
 Piezo material is very rugged
 Have very high natural frequency
 Linear over amplitude
 Insensitive to EM radiation (can be used in every conditions )
 No effect of radiations
 Tourmaline is stable at high temperature also (even sensor works at 1000°C)
 As piezo material is sensitive to pressure, some are also sensitive to
temperature they are called as pyroelectrical.

Figure 3.1 Piezo sensor
The piezoelectric sensor shown in figure 3.2 is of tourmaline material. It is
very effective for daily usage because it can bear high temperature; it is rough and
is linear over amplitude. The material with no centre of symmetry then it will
exhibit the property of piezoelectricity.
3.3.1 Geometry
Everyone thinks that a simple material having ordinary crystal has a
property of producing electrical spike, what it has that make him doing such a
wonderful job. Questions arises in mind that
 What make it different from other materials?
 Are any free electrons present in its atom?
 Is this material exhibit the property of magnet and coil?
The answer to these questions is present in the structure of the piezoelectric
material. The answer to why an electric spike produces when subjected to pressure
lives behind its structure of crystal.final year matlab projects in chennai
Most piezoelectric material is ionic salts containing cat ions and anions,
these ions form a unit cell. The crystal of piezoelectric material contains three
dimensional array of unit cell. The unit cell has a positive charge centre and
negative charge centre. If these centre are at same place i.e. centre coincide then
there will be no electrical dipole and hence no spike. But if their centres do not

coincide then the electrical spike value will be according to the magnitude of
charges and distance of positive and negative charges. There are symmetric and
asymmetric unit cell and vibration or strain causes every unit cell to distort but the
symmetric cell’s centre will continue to coincide after stress. In case of asymmetric
cell, force will cause the centre of positive and negative changes which will create
electrical voltage. There are 32 unit cells from which 20 have piezoelectric
property because they are asymmetric.
3.3.1.1 Constant of piezoelectricity
It is defined as the ratio of strain (pressure/length) over applied electric field i.e.
d = ————————– 3.1
Its units are
i.e. meter per volts.
Quartz (SI) has d = 3×
It will change its thickness up to 3nm when kilovolts are applied across its faces.
3.3.1.2 Electromechanical coupling constant
Electromechanical coupling constant K, this constant shows the conversion
of electrical energy to mechanical energy or vice versa, so we can check the piezo
electric effect by this constant also.
3.3.1.3 Materials
There are many materials which has the property of piezo electricity i.e.
 Quartz SI
 Ammonium dihydrogenphosphate ADPN
 Potassium sodium tartrate KNa
 Rochelle salt

Except quartz all others have strong piezo electric effect and are used in low cost
project because their strength is weak.
3.3.2 Working of piezoelectric sensor
This effect is due to its geometry which contains a unit cell. The unit cell of
piezoelectric material has a cubic shape which contain positive charges at all its
ends as shown in figure 3.3(a). In this figure we are discussing only those materials
which has asymmetric nature because otherwise no voltage spike will produce and
no working will be there. We actually want to produce electric charges or field
from movement of charges so it is our prime objective to produce voltage and
current. Now we are going towards working principle
Initially no pressure is applied on the unit cell so positive charge is at centre
and length between positive and negative is same. When stress, pressure or
vibration is applied to material then the spacing between the positive and negative
charge increases which cause a voltage to produce and we will sense it by any
device or we will use it for our benefit or power requirements. The Figure 2(b)
shows the unit cell after stress is appliedIt’s clear in above picture that the positive
charge has been misplaces from its original position which means the spacing
between them changes. Space change shows the voltage spike which means its
comfortable to use them as power generation.
3.3.3 Usage of piezoelectric sensor
Due to his property it canbe used in many applications i.e.
Piezoelectric sensors is perfect contrivance for the measurement of various
processes. They are used for eminence assertion, progression manage and for
research and development in many different industries. It was only in the 1950s
that the piezoelectric effect on track for industrial usage. Since then it can be

regarded as a grown-up technology with an stupendous steadfastness. It has been
fruitfully used in various applcations such as
 Medical
 Aerospace
 In nuclear instrumentation
 Touch pads of cell phones
 Power generations
 In Toys
 In microphone and ultrasound detector
 Convert oscillations of diaphragm(caused by wave) into electrical signal
 Iginition devices
 Electronics lighter
 Iginition system for gas stoves
The block explanation of a single piezoelectric sensor which is used to
convert force or pressure into electrical spike. As clear from figure that when
pressure from up or down is applied on the sensor then analog voltmeter or
galvanometer shows the deflection of few volts. If vibration is severed then it may
give spike up to 15V or in some case 30 V. This single has very low power rating
because its current is low so we combined them to make desired output. The
working of this sensor is easily understood by the block diagram in figure 3.4.
Figure 3.3 Piezo voltage checking
3.4 Already developed systems

 Fly wheel and gear arrangement
 Stair case and faraday’s law arrangement
 Rack & Pinion and chain Sprocket arrangement
3.5 Proposed system
Our proposed system contains following parts
 Piezo electric sensor
 Full-wave bridge rectifier
 Battery charger unit
 12 V, 1.2 Amp Lead battery
 Inverter
 Transformer
 AC loads
 DC loads
We are using piezo sensor of tourmaline material shown in figure 3.2, the
output of this single sensor was not as much as we need so make a series and
parallel combinations of piezo electric sensor. But making this become a challenge
because it involve mechanical design also like to press all piezo sensors together
we need springs and wooden sheets. So the parts of piezo electric sensor are
3.5.1 Piezo electric sensor
Instead of making tiles we use wooden sheets like shown in above figure
(taken by camera) for the purpose of stepping. All four sides of two sheets are
connected by nut and bolt. Piezo sensors are placed on the bottom plate on which
holes of diameter 0.5mm less than piezo diameter are drilled. 80 piezo sensors like
shown in figure3.2 are placed on the lower plate which upper plate also has holes
of diameter equal to diameter of spring. These spring are unguided and are placed
on the piezo to provide stress them so that they vibrate and we get the required
output.
There will be third plate on these two plates on which we place step or
drive the tire of vehicle so that it can press the bundles of spring which would
cause the piezo to presses and we would get required output.

Actually we make three same sets of plates which are as similar to tiles of floor so
that by simply walking on them we get the required output.
We are using spring to make our sensor works because we are using 80
piezo sensors so we cannot press them simultaneously by foot, we tried much to
get rid of these springs but we were not able to get good output without these
springs so we are using spring of much tensile strength so that they can bear the
weight of a person and also has not much compressive force so that first we have
to provide enough force to overcome spring force.
Piezo
These are piezo sensors which are in amount of 80 and are on the lower
plate and a spring from the upper plate is place on this piezo which is compressed
by the third plate on which we step. These piezo plates are pasted on the lower
plate which a hole of diameter slightly less than the diameter of the piezo sensor as
shown above.
Rectifier
The piezo sensor produces AC spikes so we have to rectify it before
sending to battery because battery stores only DC. We tried half wave rectification
by simple diode but we cannot get output because already current was very low by
clipping one cycle the power rating becomes half and hence we are in loss. Then
we tried full-wave bridge rectifier and got the result. But the problem was that we
have to connect bridge rectifier with every piezo sensor which was a challenge but
we made it.
Battery charger circuit
To charge a battery we need a charge controller which is important part of
electronics portion of our project and will be discussed clearly later as we will start
electronics chapter. LM 338 and LM 358 are ICs used in this circuit.
Battery
We are using Lead Acid battery of 12 V and current of 1.2 Amp. We want to
store charges so that we can use the power generated by foot step not only in busy
hour but also in other part of the day.
Inverter

Inverter is used to run AC loads and we are storing in battery which stores
DC but our load is AC so we use inverter. TIP 122 and TIP 127 are main ICs of
our circuit.
Transformer
Transformer is part of inverter. We are using center tape transformer of 12+12 V /
220 V.
4.0 BATTERY CHARGER CONTROL CIRCUITRY
We have arrangement of piezo sensors so that we want to control charging
and discharging of the battery. In other words we want to protect the battery from
over charging effects which could damage the battery.
Actually we used 12V Lead acid battery in this project. We set specific voltages
for battery charging and after indication of full battery; there is cut-off system to
remove the battery from charging circuitry.
4.1 Schematic diagram

Figure 4.1 Schematic diagram of battery charger circuit
4.1.1 List of components
 LM358
 Capacitor 100n
 Potentiometer 5k
 Resistor 10k
 Transistor 2N2219
 Capacitor 100u
 Zener diode 1N5233B
 LM338
 LED
 Resistor 4.7k
4.1.2 Working principle of LM358
 This IC contains dual low noise amplifiers which operate on single power
supply.
 It is a versatile, rugged workhorse with a thousand uses, from amplifying
signal from variety of transducers or any other op-amp function.
4.1.2.1 Features
 It has large DC voltage gain up to 100dB.

 Its response bandwidth is up to 1MHz (temperature compensated).
 Its supply assortment is broad,
 For single supply 3VDC to 32vDC
 For double supply 1.5VDC to 16VDC
 Its input offset voltage and current is low
4.1.2.2 Applications
 All conventional op-amp circuits.
 Transducers amplifier.
4.1.3 Capacitor
 There are basically two types of capacitors
Polar capacitor
Non-polar capacitor
Polar capacitors are that capacitors who have proper polarity mean positive
and negative terminals. In other words we can say that they have embedded
polarity as shown in figure 4.3 and they have effect on circuitry of their terminals
but in case of non-polar capacitors don’t have specific positive and negative
terminals as shown in figure 4.4, we can connect them in circuit without taking any
care of terminals.
4.1.4 Transistor
Transistor is basically a semiconductor device consist of three layers either
two p- and one n-type layer or one n- and two p-type layers called pnp and npn
transistor respectively.
4.1.4.1 Types of transistor
There are basically three types (configurations) of bipolar transistor,
1. Common base configuration
2. Common collector configuration
3. Common emitter configuration

Each configuration has its own properties and results used in different kinds of
circuits according to the requirement. While field effect transistor, terminals are
gate, drain and source. Voltage at gate is resolute by current among drain and
source.
4.1.4.2 Transistor as switch
When the transistor is biased in the saturation or cut-off region then it can be used
as switch.http://www.embeddedinnovationlab.com
Figure 4.5 Characteristic graph of transistor
In cutoff mode transistor is fully off and its working state of affairs are zero base
current, zero collector current and maximum collector to emitter voltage.
4.1.4.3 Advantages
 Vacuum tube, transistor and integrated circuits
 More trustworthy
 Lesser in volume
 Less power utilization
 Lower voltages

 Less heat
 More strong
4.1.4.4 Limitations
 Transistor has limited power handling capabilities.
 In use temperature range of transistor is kept usually 50-60 degree Celsius.
 The least signal that can be functional to transistor is restricted by the
interior noise ended by the transistor.
 The minimum collector current have to be bigger than the saturation current
Ico, which is noticeably less than 100 microamperes in the majority junction
types.
4.1.5 Zener diode
Figure 4.7 Zener diode
4.1.5.1 Working principle
The zener region of figure 4.8 is shown below. The attribute drops in an
almost straight down method at a reverse bias potential denoted by Vz. The reality
that arch drops down and away from the horizontal axis before up and away for the
positive voltage Vf area reveals that the current in the zener region has a path
reverse tothat of a forward biased diode. http://www.embeddedinnovationlab.com

Figure 4.8 Characteristic graph of zener diode
The minor gradient to the curve in the zener region reveals that there is an intensity
of resistance to be connected with the zener diode in conduction mode.
4.1.6 Working principle of LM338
It is positive voltage regulator of 12V.
It has capability to supply current of 5A.
4.1.6.1 Features
 Output is short-circuited sheltered
 Thermal regulation
 Modifiable yield along to 1.2V
 Current limit stable with temperature
4.1.6.2 Applications
 Adjustable power supplies
 Battery charger circuits
 Constant current regulators
4.2 How does it work???

For battery charging we use positive voltage regulator of 12V. We are
using voltage divider at adjust pin of the regulator, by using this we adjust 14V for
battery charging. Then we use LM358 as comparator configuration.
When battery will charge up to 14V then comparator circuit will active and
battery charging will cutoff through transistor which will act like switch here.
In comparator circuit we use a zener diode of 5.1V as a reference and
second signal of 5.3V. As the battery will fully charged then comparator circuit
will activate and will cut off the battery from charging.
5.0 BATTERY
Battery consists of electrochemical cells to store electricity house in a
single unit. In battery stored chemical energy is transformed into electrical energy.
Some batteries are used once and some of them are rechargeable. Large batteries
also provide stand by operation i.e. mobile, laptops etc.
5.1 Types of batteries
Mainly batteries are divided into two categories
1. Primary batteries
2. Secondary batteries
5.1.1 Primary batteries
Primary batteries can produce current immediately on meeting. Disposable
batteries are planned to be used once and useless. These are most usually used in
handy devices that have low current drain, are only used occasionally, or are used
well away from a different power source, such as in alarm and communication
circuits where other electric power is only occasionally available. Disposable
primary cells cannot be constantly recharged, since the chemical reactions are not
easily reversible and active materials may not return to their original forms. Battery
manufacturers propose against attempting recharging primary cells.
5.1.2 Secondary batteries

These batteries are charged before use. Charging is done by applying
current which reverse the chemical reaction that take place for the period of use.
The devices which are used to charge this type of batteries which provide rated
value of current known as charger.
The oldest form of rechargeable battery is the lead-acid battery. This
battery is prominent in that it consists of a liquid in an unsealed pot requiring that
the battery be kept standing and the area be well ventilated to make certain safe
spreading of the hydrogen gas formed by these batteries throughout overcharging.
The lead-acid battery is also very heavy for the amount of electrical energy it can
supply. Although, it’s low built-up cost and its high flow current levels make its
use common.
6.0 INVERTER
Inverter is a combination of such components which converts DC signal
into AC signal.
In this project we designed inverter which consists of following parts
1. Sine wave oscillator
2. Drive circuitry
3. Transformer
6.1 Sine wave oscillator
We designed this oscillator such that it gives us pure sinusoidal wave form.
That wave form has 10Vp-p of frequency 50Hz. In this oscillator we can vary the
frequency according to our own requirement but up to some extent.
Schematic diagram
PCB Layout
Components
 Battery
 LM358N
 Capacitor 1u
 Zener diode 1N5223B

 Resistor 330k
 Resistor 10k
 Capacitor 5p
 Resistor 51ohm
 Capacitor 470n
 Resistor 100k
6.2 Drive circuitry
The output comes from sine wave oscillator is given to the drive circuitry
which consist of TIP122 and TIP127. By using these two components we increase
the overall current of that wave form.
6.2.1 Schematic diagram
Figure 6.4 Drive circuitry of inverter
6.2.2 Components
 Resistor 4.7k

 TIP 122
 TIP 127
6.2.2.1 Working of TIP122
 TIP122 pin configuration
 Its base current is 120mA, its mean that it works only for positive cycle of
the wave.
 When it becomes active it behaves like short circuit.
 At negative cycle voltage appear across collector.
6.2.2.2 Working of TIP127
 Its base current is -120mA, its mean that it works only for negative cycle of
the wave.
 When it becomes active it behaves like short circuit.
 At positive cycle voltage appear across collector.
6.3 Transformer
Transformer is a device which is used to step up and step down the voltages
according to our own requirement without changing frequency.
6.3.1 Working principle
Transformer has two types of winding as shown in figure 6.5
1. Primary winding
2. Secondary winding
Mainly transformer work on the principle of mutual induction
6.3.1.1 Mutual induction
When alternating current pass through the primary winding then it produces
the changing flux due to the production of magnetic field in the primary winding.
As the amplitude of current increases, flux will increase. Then this changing flux
will pass through the secondary winding of the transformer due to which current
will induce in the secondary winding. This whole process is known as mutual
induction.

The voltage induced across the secondary is due to Faraday’s law of
electromagnetic induction, which states that “Rate of change of flux linkage is
equal to the induced emf.”
E=N ——————————- 6.1
Where ‘E’ is the induced emf and ‘N’ is the number of turns in equation 1.
6.3.2 Centre tapped Transformer
We use centre tap transformer as shown in figure 6.6 in the project of following
rating
Voltage 12+12V to 220V
Current 1.2 Amperes
A centre tapped transformer works when a magnetic field is generated
about the winding as alternating current passes during it. Alternating current occurs
when a secondary winding is come within the magnetic field producing an
alternating current inside this winding. Within the primary winding, alternating
current induces an alternating magnetic flux. The flux flows in the region of the
ferromagnetic core as it varies direction with each cycle. Another alternating
current is then created in every turn of the secondary windings by the alternating
flux in the core. In our project we use this transformer to transform 12V to 220V.
7.0 RECTIFIER
Rectification is the process in which input signal is being clipped or
removed after passing through the arrangement of diodes. This process is known as
rectification.
There are two types of rectification
1. Half wave rectification
2. Full wave rectification
7.1 Half wave rectification

In this process half wave of the input signal is clipped after passing through
the diodes as shown in figure 7.1
As we see in the figure 7.1 that only negative cycle of the input signal is
eliminated that’s why we call this process half wave rectification.
7.2 Full wave rectification
In this process full wave of the input signal is moved toward positive side
after passing through the diodes as shown in figure 7.2
As we see in whole input signal is diverted into positive side of the voltage.
In our project we use full wave rectifier after each piezoelectric sensor.
Because sensor give us AC spikes so we use full wave rectifier to covert the AC
voltage to DC voltage. We did this transformation of voltage for storage purpose in
the battery because battery can store only DC voltages.

Keywords
 Final year ece projects in chennai
 Final year embedded systems projects in chennai
 Final year mechanical projects in chennai
 Final year eee projects in chennai
 Final year ece projects in bangalore
 Final year vlsi projects in chennai
 Final year vlsi projects in bangalore
 Final year engineering projects in chennai
 Final year engineering projects in bangalore
 Final year projects in chennai
 Final year projects in bangalore
Address:
Embedded Innovation Lab
Bangalore ,chennai

final year embedded systems projects in chennai

Recomendados

Recomendados

Mais conteúdo relacionado

Mais procurados

Mais procurados (19)

Semelhante a final year embedded systems projects in chennai

Semelhante a final year embedded systems projects in chennai (20)

Mais de Ashok Kumar.k

Mais de Ashok Kumar.k (11)

Último

Último (20)

final year embedded systems projects in chennai