Cell Phone Operated Robot Report

7/21/2019 Cell Phone Operated Robot Report

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1. INTRODUCTION

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1. INTRODUCTION:

Cell phone operated robot is a machine that can be controlled with a mobile. In this project,

the robot is controlled by a mobile phone that makes a call to the mobile phone attached to

the robot. In the course of a call, if any button is pressed, a tone corresponding to the button

pressed is heard at the other end of the call. This tone is called "Dual Tone Multiple

!reuency" #DTM!$ tone. The robot percei%es this DTM! tone with the help of the phone

stacked on the robot. The recei%ed tone is processed by the microcontroller with the help of

DTM! decoder. The microcontroller then transmits the signal to the motor dri%er ICs to

operate the motors & our robot starts mo%ing Con%entionally, 'irelesscontrolled robots use

rf circuits, which ha%e the drawbacks of limited working range, limited freuency range and

the limited control. (se of a mobile phone for robotic control can o%ercome these limitations.

It pro%ides the ad%antage of robust control, working range as large as the co%erage area of the

ser%ice pro%ider, no interference with other controllers and up to twel%e controls. )lthough

the appearance and the capabilities of robots %ary %astly, all robots share the feature of a

mechanical, mo%able structure under some form of control. The Control of robot in%ol%es

three distinct phases* perception, processing and action. +enerally, the preceptors are sensors

mounted on the robot , processing is done by the onboard microcontroller or processor, and

the task is performed using motors or with some other actuators.

In this project the robot, is controlled by a mobile phone that makes call to the mobile phone

attached to the robot in the course of the call, if any button is pressed control corresponding

to the button pressed is heard at the other end of the call. This tone is called dual tone multi

freuency tome #DTM!$ robot recei%es this DTM! tone with the help of phone stacked in

the robot.

The recei%ed tone is processed by the atmega- microcontroller with the help of DTM!

decoder MT/0 the decoder decodes the DTM! tone in to its eui%alent binary digit andthis binary number is send to the microcontroller, the microcontroller is preprogrammed to

take a decision for any gi%e input and outputs its decision to motor dri%ers in order to dri%e

the motors for forward or backward motion or a turn. The mobile that makes a call to the

mobile phone stacked in the robot acts as a remote. 1o this simple robotic project does not

reuire the construction of recei%er and transmitter units. DTM! signaling is used for

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telephone signaling o%er the line in the %oice freuency band to the call switching center. The

%ersion of DTM! used for telephone dialing is known as touch tone.

DTM! assigns a specific freuency #consisting of two separate tones$ to each key s that it

can easily be identified by the electronic circuit. The signal generated by the DTM! encoder

is the direct algebraic submission, in real time of the amplitudes of two sine #cosine$ wa%es

of different freuencies, i.e., pressing 2 will send a tone made by adding 33- 45 and //0 45

to the other end of the mobile. The important components of this robot are DTM! decoder,

Microcontroller and motor dri%er.

)n MT/0 series DTM! decoder is used here. )ll types of the mt/0 series use digital

counting techniues to detect and decode all the si6teen DTM! tone pairs in to a four bit

code output. The built in dial tone rejection circuit eliminated the need for pre filtering.

'hen the input signal gi%en at pin7 #I8$ single ended input configuration is recogni5ed to

be effecti%e, the correct four bit decode signal of the DTM! tone is transferred to 9 #pin$

through 9:#pin:$ outputs.

DTM! Mobile ;


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2.

REVIEW

OF

LITERATURE

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2. REVIEW OF LITERATURE:

This Cellphone , is the original prototype

of all modernday uninhabited aerial %ehicles and precision guided weapons. In fact, it is

among all remotely operated %ehicles in air, land or sea. ?owered by leadacid batteries

and an electric dri%e motor, the %essel was designed to be maneu%ered alongside a target

using instructions recei%ed from a wireless remotecontrol transmitter. 3)

and ;uhrstahl@s 1D:00, known as !rit5,@ both airlaunched, primarily against ships

at sea.

DTM! is the most common telecommunications signaling method used in )ustralia.

DTM! stands for Dual Tone Multiple !reuencyE it is used to send information through

phone lines to and from local e6change. Dual Tone Multiple !reuency #DTM!$ is also

known as Touchtone, Tone Dialing, B! 1ignaling and M! Dialing F/G. Aach DTM! tone

consists of two simultaneous tones #one from the high group and one from the lowgroup$, which are used to indicate which number or symbol that is press on the

telephoneHs keypad. !or e6ample if number 2 is pressed in telephoneHs keypad, the tones

that will hear are 33- 45 and //0 45 played simultaneously.

Dual Tone Multiple !reuency is the basis of %oice communications control. Modern

telephone circuits use DTM! to dial numbers, configure telephone e6changes

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#switchboards$ from remote locations, program certain euipment and so on. )lmost any

mobile phone is capable of generating DTM!, pro%iding a connection has already been

established. This is for the use of phone bankingE %oicemail ser%ices and other DTM!

controlled applications. DTM! was designed so that it is possible to use acoustic transfer.

The DTM! tones can be sent from a standard speaker and be recei%ed using a standard

microphone #pro%iding it is connected to a decoding circuit of some type$. DTM! tones

are simply two freuencies played simultaneously by a standard home phonefa6 or

mobile phone. Aach key on your telephoneHs keypad has a uniue freuency assigned to

it. 'hen any key is pressed on your telephoneHs keypad the circuit plays the

corresponding DTM! tone and sends it to your local e6change for processing. DTM!

tones can be imitated by using a 'hite =o6 or Tone Dialer. It is also possible to record

DTM! tones using a tape recorder or computer microphone and then played into the

mouthpiece of your telephone to dial numbers. 4owe%er if there is a significant amount

of background sound behind the recorded DTM! tones, the tones may not work properly

and cause problems when trying to dial numbers.

=elow is a Dual Tone Multi !reuency #DTM!$ map for a ::matri6 keypad, the map

shows each uniue freuency which is assigned to each key on a standard :: telephone

keypad. The freuencies are e6actly the same for a 3: matri6 keypad, without the keys

), =, C and D. 4owe%er, this is not a standard keypad. This keypad has : more keys than

a standard keypad #3:matri6$. The keys ), =, C and D are not commonly used on

standard home phonefa6, office phone or payphone. Aach of the keys ), =, C and D are

system tonescodes and are mainly used to configure telephone e6changes or to perform

other special functions at an e6change. !or e6ample, the corresponding tonecode

assigned to the ) key is used on some networks to mo%e through %arious carriers #this

function is prohibited by most carriers$.

!ilter is one of the %ery important de%ices of this DTM! technology. 'hen DTM! was

created indi%idual and uniue freuencies were chosen so that it would be uite easy to

design freuency filters and so that the tones could easily pass through telephone lines #the

ma6imum guaranteed bandwidth for a standard telephone line e6tends from around 300

45 to 3.2 k45$. DTM! was not intended for data transferE it was designed for control

signals only. 'ith a standard DTM! encoderdecoder, it is possible to signal at a rate of

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around 0 tonessignals per second. ) standard DTM! tone should always be played for at

least 20ms with a further 20ms space duration for ma6imum reliability. The contemporary

mobile keypad is laid out in a 36: grid, although the original DTM! keypad had an

additional column for four menu selector keys. 'hen used to dial a telephone number,

pressing a single key will produce a pitch consisting of two simultaneous pure tone

sinusoidal freuencies. The row in which the key appears determines the freuency, and

the column determines the high freuency. !or e6ample, pressing the key will result in a

sound composed of both ->/ 45 and 70> 45 tone F, 2G. The original keypads had

le%ers inside, so each button acti%ated two contacts. The multiple tones are the reason for

calling the system multi freuency. These tones are then decoded by the switching center

to determine which key was pressed.

!ig 7. Dual Tone Multi !reuency #DTM!$ map.

DTM! stands for dual tone multiple freuency. DTM! is a term which used in telephone

industry. DTM! generation is a composite audio signals of two tones between the freuency

of ->/45 and -3345. The DTM! keypad is arranged such that each row will ha%e its own

uniue tone freuency and also each column will ha%e its own uniue tone. =elow is a

representation of the typical DTM! keypad and the associated rowcolumn freuencies.

'hen any of the key like "", "7", "J", "K" etc is pressed particular code is transmitted. This

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code is consist of two freuency among which one is higher freuency and second one is

lower freuency 'hen any DTM! code has been recei%ed at mobile phone it can be audible

through speaker. 1o to decode this DTM! code speaker output itself can be used.


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3. MAT4


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3.1 BLOCK DIAGRAM

!ig 3... =lock diagram

3.2 CIRCUIT DIAGRAM

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https://www.elprocus.com/wp-content/uploads/2014/08/7-31-2014-1-00-58-PM.jpg


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!ig 3.7.7. Circuit diagram

3.2.1 SIMPLIFIED CIRCUIT DIAGRAM

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!ig 3.7..3. 1implified Circuit Diagram

3.3 ACTUAL VIEW

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!ig 3.3.:. )ctual Biew

3.4 COMPONENTS REQUIRED

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1.8


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effecti%e, the correct :bit decode signal of the DTM! tone is transferred to 9 #pin $

through 9: #pin :$ outputs. Table II shows the DTM! data output table of MT/0. 9

through 9: outputs of the DTM! decoder #IC$ are connected to port pins ?)0 through ?)3

of )Tmega- microcontroller #IC7$ after in%ersion by 8 through 8:, respecti%ely. The

)Tmega- is a lowpower, bit, CM


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The microcontroller output is not sufficient to dri%e the dc motors, so current dri%ers are

reuired for motor rotation. The 7>3D is a uad, highcurrent, halfh dri%er designed to

pro%ide bidirectional dri%e currents of upto-00m) at %oltages from :.2B to 3-B. It makes it

easier to dri%e the dc motors. The 7>3D consists of four dri%ers. pins I8 through I8: and

$ enables

dri%ers 3 and :. The recei%ed tone is processed by the )Tmega- microcontroller with the

help of DTM! decoder MT/0. The decoder decodes the DTM! tone into its eui%alent

binary digit and this binary number is sent to the microcontroller. The microcontroller is

preprogrammed to take a decision for any gi%en input and outputs its decision to motor

dri%ers in order to dri%e the motors for forward or backward motion or a turn. The mobile

that makes a call to the mobile phone stacked in the robot acts as a remote. 1o this simple

robotic project does not reuire the construction of recei%er and transmitter units. DTM!

signaling is used for telephone signaling o%er the line in the %oicefreuency band to the call

switching centre. The %ersion of DTM! used for telephone tone dialing is known as OTouch

Tone.@ DTM! assigns a specific freuency #consisting of two separate tones$ to each key so

that it can easily be identified by the electronic circuit. The signal generated by the DTM!

encoder is a direct algebraic summation, in real time, of the amplitudes of two sine #cosine$

wa%es of different freuencies, i.e., pressing O2@ will send a tone made by adding 33- 45

and //0 45 to the other end of the line.

If any button is pressed control corresponding to the button pressed is heard at the other end

of the call. This tone is called dual tone multi freuency tome #DTM!$ robot recei%es this

DTM! tone with the help of phone stacked in the robot

The recei%ed tone is processed by the atmega- microcontroller with the help of DTM!decoder MT/0 the decoder decodes the DTM! tone in to its eui%alent binary digit and

this binary number is send to the microcontroller, the microcontroller is preprogrammed to


the motors for forward or backward motion or a turn.

The mobile that makes a call to the mobile phone stacked in the robot acts as a remote. 1o

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this simple robotic project does not reuire the construction of recei%er and transmitter units.

DTM! signaling is used for telephone signaling o%er the line in the %oice freuency band to

the call switching center. The %ersion of DTM! used for telephone dialing is known as touch

tone. DTM! assigns a specific freuency #consisting of two separate tones$ to each key s that

it can easily be identified by the electronic circuit. The signal generated by the DTM!

encoder is the direct algeabric submission, in real time of the amplitudes of two sine#cosine$

wa%es of different freuencies, i.e. ,pressing 2 will send a tone made by adding 33-h5 and

//0h5 to the other end of the mobile.

)n MT/0 series dtmf decoder is used here. )ll types of the mt/0 series use digital

counting techniues to detect and decode all the si6teen DTM! tone pairs in to a four bit

code output. The built in dial tone rejection circuit eliminated the need for pre filtering.

'hen the input signal gi%en at pin7 #I8$ single ended input configuration is recogni5ed to

be effecti%e, the correct four bit decode signal of the DTM! tone is transferred to 9 #pin$

through 9:#pin:$ outputs. The atmega - is a low power, bit, cmos microcontroller based

on the )B; enhanced ;I1C architecture. It pro%ides the following feature* -kb of in system

programmable flash memory with read write capabilities, 27bytes of AA?;3d

ic: cd/00:

r,r7 00k ohm

r3 330k ohm

r:r 0k ohm

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c 0.:/ microfarad

c7,c3,c2,c- 77 picofarad

c: 0. microfarad

6tal 3.2/ mh5

6tal7 7 mh5

s push to on switch

m,m7 -% 20 rpm

battery -%

3.6 COMPONENT DISCRIPTION

3.6.1 L293D IC

7>3D is a dual 4bridge motor dri%er integrated circuit #IC$. Motor dri%ers act as current

amplifiers since they take a lowcurrent control signal and pro%ide a highercurrent signal.

This higher current signal is used to dri%e the motors.

7>3D contains two inbuilt 4bridge dri%er circuits. In its common mode of operation, two

DC motors can be dri%en simultaneously, both in forward and re%erse direction. The motor

operations of two motors can be controlled by input logic at pins 7 & / and 0 & 2. Input

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logic 00 or will stop the corresponding motor. ogic 0 and 0 will rotate it in clockwise

and anticlockwise directions, respecti%ely.

Anable pins and > #corresponding to the two motors$ must be high for motors to start

operating. 'hen an enable input is high, the associated dri%er gets enabled. )s a result, the

outputs become acti%e and work in phase with their inputs. 1imilarly, when the enable input

is low, that dri%er is disabled, and their outputs are off and in the highimpedance state.

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!ig.3.-..2. 7>3D IC

3.6.2 CRSTAL OSCILLATOR :

) crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a

%ibrating crystal of pie5oelectric material to create an electrical signal with a %ery precise

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freuency. This freuency is commonly used to keep track of time #as in uart5

wristwatches$, to pro%ide a stable clock signal for digital integrated circuits, and to stabili5e

freuencies for radio transmitters and recei%ers. The most common type of pie5oelectric

resonator used is the uart5 crystal, so oscillator circuits incorporating them became known

as crystal oscillators, but other pie5oelectric materials including polycrystalline ceramics are

used in similar circuits.

9uart5 crystals are manufactured for freuencies from a few tens of kilohert5 to hundreds of

megahert5. More than two billion crystals are manufactured annually. Most are used for

consumer de%ices such as wristwatches, clocks, radios, computers, and cell phones. 9uart5

crystals are also found inside test and measurement euipment, such as counters, signal

generators, and oscilloscopes.

!ig.3.-.7.- Crystal


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) microcontroller is a single chip that contains the processor #the C?($, non%olatile memory

for the program #;


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)Tmega-is an bit high performance microcontroller of )tmel@s Mega )B; family with

low power consumption. )tmega- is based on enhanced ;I1C#;educed Instruction 1et

Computing, Pnow more about ;I1C and CI1C )rchitecture$ architecture with 3 powerful

instructions. Most of the instructions e6ecute in one machine cycle. )tmega- can work on

ama6imum freuency of -M45.)Tmega- has - P= programmable flash memory, static

;)M of P= and AA?;


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T air time #-0 byte data W -0kbs X .72ms preamble$, a full -0 byte packet can be

transmitted Collision a%oidance #isten before transmit$ functions can be enabled to pre%ent

loss of packets. Data packets may be sent with either normal or e6tended preamble. A6tended

preamble is used if the remote !;?C7 is in power sa%e mode. A6tended preamble length can

be changed in the AA?;


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The MT/0 is a complete DTM! recei%er integrating both the band split filter and digital

decoder functions. The filter section uses switched capacitor techniues for high and low

group filtersE the decoder uses digital counting techniues to detect and decode all - DTM!

tonepairs into a :bit code. A6ternal component count is minimi5ed by on chip pro%ision of

a differential input amplifier, clock oscillator and latched threestate bus interface.

This circuit detects the dial tone from a telephone line and decodes the keypad pressed on the

remote telephone. The dial tone we heard when we pick up the phone set is call Dual Tone

Multi!reuency, DTM! in short. The name was gi%en because the tone that we heard o%er

the phone is actually make up of two distinct freuency tone, hence the name dual tone. The

DTM! tone is a form of one way communication between the dialer and the telephone

e6change. ) complete communication consist of the tone generator and the tone decoder. Inthis article, we are use the IC MT/0DA, the main component to decode the input dial tone

to 2 digital output. These digital bits can be interface to a computer or microcontroller for

further application eg. remote control, phone line transfer operation, ADs, etc.

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!ig 3.-.:.. DTM! decoder

3.6.5 DC MOTOR :

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) DC motor is a class of electrical machines that con%erts direct current electrical power

into mechanical power. The most common types rely on the forces produced by magnetic

fields. 8early all types of DC motors ha%e some internal mechanism, either

electromechanical or electronic, to periodically change the direction of current flow in

part of the motor. Most types produce rotary motionE a linear motor directly produces

force and motion in a straight line.

DC motors were the first type widely used, since they could be powered from e6isting

directcurrent lighting power distribution systems. ) DC motorHs speed can be controlled

o%er a wide range, using either a %ariable supply %oltage or by changing the strength of

current in its field windings. 1mall DC motors are used in tools, toys, and appliances. The

uni%ersal motor can operate on direct current but is a lightweight motor used for portable

power tools and appliances. arger DC motors are used in propulsion of electric %ehicles,

ele%ator and hoists, or in dri%es for steel rolling mills. The ad%ent of power electronics

has made replacement of DC motors with )C motors possible in many applications.

) coil of wire with a current running through it generates an electromagnetic field aligned

with the center of the coil. The direction and magnitude of the magnetic field produced

by the coil can be changed with the direction and magnitude of the current flowing

through it.

!ig.3.-.2.> DC Motor

) simple DC motor has a stationary set of magnets in the stator and an armature with one

more windings of insulated wire wrapped around a soft iron core that concentrates the

magnetic field. The windings usually ha%e multiple turns around the core, and in large

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motors there can be se%eral parallel current paths. The ends of the wire winding are

connected to a commutator. The commutator allows each armature coil to be energi5ed in

turn and connects the rotating coils with the e6ternal power supply through brushes.

#=rushless DC motors ha%e electronics that switch the DC current to each coil on and off

and ha%e no brushes.$The total amount of current sent to the coil, the coilHs si5e and what

itHs wrapped around dictate the strength of the electromagnetic field created. The

seuence of turning a particular coil on or off dictates what direction the effecti%e

electromagnetic fields are pointed. =y turning on and off coils in seuence a rotating

magnetic field can be created. These rotating magnetic fields interact with the magnetic

fields of the magnets #permanent or electromagnets$ in the stationary part of the motor

#stator$ to create a force on the armature which causes it to rotate. In some DC motor

designs the stator fields use electromagnets to create their magnetic fields which allow

greater control o%er the motor.

)t high power le%els, DC motors are almost always cooled using forced air. Different

number of stator and armature fields as well as how they are connected pro%ides different

inherent speedtorue regulation characteristics. The speed of a DC motor can be

controlled by changing the %oltage applied to the armature. The introduction of %ariable

resistance in the armature circuit or field circuit allowed speed control. Modern DC

motors are often controlled by power electronics systems which adjust the %oltage by

"chopping" the DC current into on and off cycles which ha%e an effecti%e lower %oltage.

1ince the serieswound DC motor de%elops its highest torue at low speed, it is often

used in traction applications such as electric locomoti%es, and trams.

The DC motor was the mainstay of electric traction dri%es on both electric and diesel

electric locomoti%es, streetcarstrams and diesel electric drilling rigs for many years. The

introduction of DC motors and an electrical grid system to run machinery starting in the

/0s started a new second Industrial ;e%olution. DC motors can operate directly from

rechargeable batteries, pro%iding the moti%e power for the first electric %ehicles and

todayHs hybrid cars and electric cars as well as dri%ing a host of cordless tools. Today DC

motors are still found in applications as small as toys and disk dri%es, or in large si5es to

operate steel rolling mills and paper machines. arge DC motors with separately e6cited

fields were generally used with winder dri%es for mine hoists, for high torue as well as

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) resistor is a twoterminal electronic component that produces a %oltage across its

terminals that is proportional to the electric current through it in accordance with


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;esistors are common elements of electrical networks and electronic circuits and are

ubiuitous in electronic euipment. ?ractical resistors as discrete components can be

composed of %arious compounds and forms. ;esistors are also implemented within

integrated circuits. ;esistors act to reduce current flow, and, at the same time, act to

lower %oltage le%els within circuits. In electronic circuits resistors are used to limit

current flow, to adjust signal le%els, bias acti%e elements, terminate transmission lines

among other uses. ;esistors are also implemented within integrated circuits. The %alue of

a resistor can be measured with an ohmmeter& which may be one function of a

multimeter.

?ractical resistors ha%e a series inductance and a small parallel capacitanceE these

specifications can be important in highfreuency applications. In a lownoise amplifier

or preamp, the noise characteristics of a resistor may be an issue. The temperature

coefficient of the resistance may also be of concern in some precision applications.

The unwanted inductance, e6cess noise, and temperature coefficient are mainly

dependent on the technology used in manufacturing the resistor. They are not normally

specified indi%idually for a particular family of resistors manufactured using a particular

technology. ) family of discrete resistors is also characteri5ed according to its form

factor, that is, the si5e of the de%ice and the position of its leads which is rele%ant in the

practical manufacturing of circuits using them.

?ractical resistors are also specified as ha%ing a ma6imum power rating which must

e6ceed the anticipated power dissipation of that resistor in a particular circuit* this is

mainly of concern in power electronics applications. ;esistors with higher power ratings

are physically larger and may reuire heat sinks. In a high%oltage circuit, attention must

sometimes be paid to the rated ma6imum working %oltage of the resistor. 'hile there is

no minimum working %oltage for a gi%en resistor, failure to account for a resistorHsma6imum rating may cause the resistor to incinerate when current is run through it.

Most a6ial resistors use a pattern of colored stripes to indicate resistance, which also

indicate tolerance, and may also be e6tended to show temperature coefficient and

reliability class. Cases are usually tan, brown, blue, or green, though other colors are

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occasionally found such as dark red or dark gray. The power rating is not usually marked

and is deduced from the si5e. The failure rate of resistors in a properly designed circuit is

low compared to other electronic components such as semiconductors and electrolytic

capacitors. Damage to resistors most often occurs due to o%erheating when the a%erage

power deli%ered to it greatly e6ceeds its ability to dissipate heat specified by the resistorHs

power rating. This may be due to a fault e6ternal to the circuit, but is freuently caused

by the failure of another component in the circuit connected to the resistor.

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3.6.$ CAPACITORS :

Capacitor is passi%e electronic component consisting of a pair of conductors separated by

a dielectric. 'hen a %oltage potential difference e6ists between the conductors, an

electric field is present in the dielectric. This field stores energy and produces amechanical force between the plates. )n ideal capacitor is characteri5ed by a single

constant %alue, capacitance, which is measured in farads. The capacitance is greatest

when there is a narrow separation between large areas of conductor, hence capacitor

conductors are often called plates, referring to an early means of construction. 'hen

there is a potential difference #%oltage$ across the conductors, a static electric field

de%elops across the dielectric, causing positi%e charge to collect on one plate and

negati%e charge on the other plate. Anergy is stored in the electrostatic field. )n ideal

capacitor is characteri5ed by a single constant %alue, capacitance, measured in farads.

This is the ratio of the electric charge on each conductor to the potential difference

between them.

Capacitors are widely used in electronic circuits for blocking direct current while

allowing alternating current to pass, in filter networks, for smoothing the output of power

supplies, in the resonant circuits that tune radios to particular freuencies, in electric

power transmission systems for stabili5ing %oltage and power flow, and for many other

purposes.

)n ideal capacitor is characteri5ed by a single constant %alue for its capacitance.

Capacitance is e6pressed as the ratio of the electric charge Qon each conductor to the

potential difference Vbetween them. The 1I unit of capacitance is the farad #!$, which is

eual to one coulomb per %olt # CB$. Typical capacitance %alues range from about p!

#0Z7

!$ to about m! #0Z3

!$.

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!ig.3.-./. Capacitor

The capacitance is greater when there is a narrower separation between conductors and

when the conductors ha%e a larger surface area. In practice, the dielectric between the

plates passes a small amount of leakage current and also has an electric field strength

limit, known as the breakdown %oltage. The conductors and leads introduce an undesired

inductance and resistance.

Capacitors are widely used in electronic circuits for blocking direct current while

allowing alternating current to pass. In analog filter networks, they smooth the output of

power supplies. In electric power transmission systems, they stabili5e %oltage and power

flow. The capacitance of certain capacitors decreases as the component ages. In ceramic

capacitors, this is caused by degradation of the dielectric. The type of dielectric, ambient

operating and storage temperatures are the most significant aging factors, while the

operating %oltage has a smaller effect. The aging process may be re%ersed by heating the

component abo%e the Curie point. )ging is fastest near the beginning of life of the

component, and the de%ice stabili5es o%er time. Alectrolytic capacitors age as the

electrolyte e%aporates.

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In contrast with ceramic capacitors, this occurs towards the end of life of the component.

Temperature dependence of capacitance is usually e6pressed in parts per million per [C.

It can usually be taken as a broadly linear function but can be noticeably nonlinear at the

temperature e6tremes.

The temperature coefficient can be positi%e or negati%e, sometimes e%en amongst

different samples of the same type. In other words, the spread in the range of temperature

coefficients can encompass 5ero. Capacitors, especially ceramic capacitors, and older

designs such as paper capacitors, can absorb sound wa%es resulting in a microphonic

effect. Bibration mo%es the plates, causing the capacitance to %ary, in turn inducing )C

current.

1ome dielectrics also generate pie5oelectricity. The resulting interference is especially

problematic in audio applications, potentially causing feedback or unintended recording.

In the re%erse microphonic effect, the %arying electric field between the capacitor plates

e6erts a physical force, mo%ing them as a speaker. This can generate audible sound, but

drains energy and stresses the dielectric and the electrolyte, if any.

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3.6.# LIG'T EMITTING DIODE :

) lightemitting diode #AD$ is a semiconductor diode that emits light when an electrical

current is applied in the forward direction of the de%ice. ADs are widely used as

indicator lights on electronic de%ices and increasingly in higher power applications such

as flashlights and area lighting ADs present many ad%antages o%er incandescent light

sources including lower energy consumption, longer lifetime, impro%ed robustness,

smaller si5e, faster switching, and greater durability and reliance.

4owe%er, they are relati%ely e6pensi%e and reuire more precise current and heat

management than traditional light sources. ADs are a%ailable in red, orange, amber,

yellow, green, and blue and white. =lue and white ADs are much more e6pensi%e than

the other colors. The color of an AD is determined by the semiconductor material, not

by the coloring of the HpackageH. ADs are a%ailable in a wide %ariety of si5es and shapes.

)n AD must ha%e a resistor connected in series to limit the current through the AD

otherwise it will burn out almost instantly. 8onetheless these diodes are %ery useful as

light emitters in %isual display units and in optically coupled circuits. They are used in

arrays of different types for displaying alphanumeric #letters and numbers$ or supplying

input power to lasers or for entering information into optical computer memories and for

numeral displays in handheld or pocket calculators.

!ig.3.-..7 ight Amitting Diode

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) lightemitting diode #AD$ is a twolead semiconductor light source. It is a basic pn

junction diode, which emits light when acti%ated. 'hen a fitting %oltage is applied to the

leads, electrons are able to recombine with electron holes within the de%ice, releasing

energy in the form of photons. This effect is called electroluminescence, and the color of

the light #corresponding to the energy of the photon$ is determined by the energy band

gap of the semiconductor. )n AD is often small in area #less than mm7$ and integrated

optical components may be used to shape its radiation pattern.

4owe%er, they are relati%ely e6pensi%e and reuire more precise current and heat

management than traditional light sources. ADs are a%ailable in red, orange, amber,

yellow, green, and blue and white. =lue and white ADs are much more e6pensi%e than

the other colors. The color of an AD is determined by the semiconductor material, not

by the coloring of the HpackageH. ADs are a%ailable in a wide %ariety of si5es and shapes.

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3.6.9 DIODE :

In electronics, a diode is a twoterminal electronic component that conducts electric

currentin only one direction. The term usually refers to a semiconductor diode, the most

common type today. This is a crystalline piece of semiconductormaterial connected to

two electrical terminals. ) %acuum tube diode is a %acuum tubewith two electrodes* a

plate and a cathode. The most common function of a diode is to allow an electric current

to pass in one direction #called the diodeHs forward direction$ while blocking current in

the opposite direction #the re%erse direction$. Thus, the diode can be thought of as an

electronic %ersion of a check %al%e. This unidirectional beha%ior is called rectification,

and is used to con%ert alternating currentto direct current,and to e6tract modulationfrom

radio signals in radio recei%ers.

!ig.3.-.>.3 Diode ;e%ersed =iased

38
http://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Vacuum_tubehttp://en.wikipedia.org/wiki/Electrodehttp://en.wikipedia.org/wiki/Plate_electrodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Check_valvehttp://en.wikipedia.org/wiki/Rectification_(electricity)http://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Direct_currenthttp://en.wikipedia.org/wiki/Modulation


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3.6.1% VOLTAGE REGULATOR :

) %oltage regulator is designed to automatically maintain a constant %oltage le%el. )%oltage regulator may be a simple "feedforward" design or may include negati%e

feedback control loops. It may use an electromechanical mechanism, or electronic

components. Depending on the design, it may be used to regulate one or more )C or

DC %oltages.

The Digital board can use any power supply that creates a DC %oltage between - and

7 %olts. ) 2B %oltage regulator #/02$ is used to ensure that no more than 2B is

deli%ered to the Digital board regardless of the %oltage present at the L7 connector#pro%ided that %oltage is less than 7BDC$.

!ig. 3.-.0.: Boltage ;egulator

Alectronic %oltage regulators are found in de%ices such as computer power supplies

where they stabili5e the DC %oltages used by the processor and other elements. In

automobile alternators and central power station generator plants, %oltage regulators

control the output of the plant. In an electric power distribution system, %oltage

regulators may be installed at a substation or along distribution lines so that all

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customers recei%e steady %oltage independent of how much power is drawn from the

line. The regulator functions by using a diode to clamp the output %oltage at 2BDC

regardless of the input %oltage e6cess %oltage is con%erted to heat and dissipated

through the body of the regulator. If a DC supply of greater than 7B is used,

e6cessi%e heat will be generated, and the board may be damaged. If a DC supply of

less than 2B is used, insufficient %oltage will be present at the regulator output. It is

mainly used in the circuit to maintain the e6act %oltage which is followed by the power

supply. ) simple %oltage regulator can be made from a resistor in series with a diode.

Due to the logarithmic shape of diode BI cur%es, the %oltage across the diode changes

only slightly due to changes in current drawn or changes in the input. 'hen precise

%oltage control and efficiency are not important, this design may work fine.

!eedback %oltage regulators operate by comparing the actual output %oltage to some

fi6ed reference %oltage. )ny difference is amplified and used to control the regulation

element in such a way as to reduce the %oltage error. This forms a negati%e feedback

control loopE increasing the openloop gain tends to increase regulation accuracy but

reduce stability. There will also be a tradeoff between stability and the speed of the

response to changes. If the output %oltage is too low #perhaps due to input %oltage

reducing or load current increasing$, the regulation element is commanded, up to a point,

to produce a higher output %oltage\by dropping less of the input %oltage #for linear series

regulators and buck switching regulators$, or to draw input current for longer periods

#boosttype switching regulators$E if the output %oltage is too high, the regulation element

will normally be commanded to produce a lower %oltage.

4owe%er, many regulators ha%e o%ercurrent protection, so that they will entirely stop

sourcing current if the output current is too high, and some regulators may also shut

down if the input %oltage is outside a gi%en range. Boltage regulators or stabili5ers are

used to compensate for %oltage fluctuations in mains power. arge regulators may be

permanently installed on distribution lines. 1mall portable regulators may be plugged in

between sensiti%e euipment and a wall outlet.

)utomatic %oltage regulators are used on generator sets on ships, in emergency power

supplies, on oil rigs, etc. to stabili5e fluctuations in power demand. !or e6ample, when a

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large machine is turned on, the demand for power is suddenly a lot higher. The %oltage

regulator compensates for the change in load. Commercial %oltage regulators normally

operate on a range of %oltages, for e6ample 20\7:0 B or >0\70 B. 1er%o stabili5ers are

also manufactured and used widely in spite of the fact that they are obsolete and use out

dated technology.

Boltage regulators are used in de%ices like air conditioners, refrigerators, tele%isions etc.

in order to protect them from fluctuating input %oltage. The major problem faced is the

use of relays in %oltage regulators. ;elays create sparks which result in faults in the

product.

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3.$ P.C.B. LAOUT AND DESIGNING:

The entire circuit can be easily assembled on a general purpose ?.C.=. board

respecti%ely.

ayout of desired diagram and preparation is first and most important operation in any

printed circuit board manufacturing process. !irst of all layout of component side is to be

made in accordance with a%ailable components dimensions.

The following points are to be obser%ed while forming the layout of ?.C.=.

. =etween two components, sufficient space should be maintained.

7. 4igh %oltagema6 dissipated components should be mounted at sufficientdistance from semiconductor and electrolytic capacitors.

3. The most important points are that the components layout is making proper

compromise with copper side circuit layout.

?rinted circuit board #?.C.=.s$ is used to a%oid most of all the disad%antages of

con%entional breadboard. These also a%oid the use of thin wires for connecting the

componentsE they are small in si5e and efficient in performance.

3.$.1 P()*+(,- C,(/0, L+0 :

!irst of all the actual si5e circuit layout is to be drawn on the copper side of the copper

clad board. Then enamel paint is applied on the tracks of connection with the help of a

shade brush. 'e ha%e to apply the paints surrounding the point at which the connection is

to be made. It a%oids the disconnection between the leg of the component and circuit

track. )fter completion of painting work, it is allowed to dry.

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3.$.2 E/,- :

The remo%al of e6cess of copper on the plate apart from the printed circuit is known as

etching. !rom this process the copper clad board with printed circuit is placed in the

solution of !eCl with 3: drops of 4C in it and is kept so for about 0 to 2 minutes

and is taken out when all the e6cess copper is remo%ed from the ?.C.=.

)fter etching, the ?.C.=. is kept in clean water for about half an hour in order to get

?.C.=. away from acidic, field, which may cause poor performance of the circuit. )fter

the ?.C.=. has been thoroughly washed, paint is remo%ed by soft piece of cloth dipped I

thinner or turbine. Then ?.C.=. is checked as per the layout, now the ?.C.=. is ready for

use.

3.$.3 D(,,- :

)fter completion of painting work, holes 73inch #mm$ diameter are drilled at desired

points where we ha%e to fi6 the components.

3.$.4 S)(,- :

1oldering is the process of joining two metallic conductor the joint where two metal

conductors are to be join or fused is heated with a de%ice called soldering iron and then

as allow of tin and lead called solder is applied which melts and con%erse the joint. The

solder cools and solidifies uickly to ensure is good and durable connection between the

jointed metal con%erting the joint solder also present o6idation.

3.$.5 S)(,- T)/-,70)8 :

These are basically two soldering techniues.

. Manual soldering with iron.

7. Mass soldering.

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3.$.6 S)(,- , ,(- :

The surface to be soldered must be cleaned & flu6ed. The soldering iron switched on and

bellowed to attain soldering temperature. The solder in form of wire is allied hear the

component to be soldered and heated with iron. The surface to be soldered is filled, iron

is remo%ed and joint is cold without disturbing.

3.$.$ S)( ,- +() 80**8) :

. ?ro%ide permanent low resistance path.

7. Make a robust mechanical link between ?.C.=. and leads of components.

3. )llow heat flow between component, joining elements and ?.C.=.

:. ;etain adeuate strength with temperature %ariation.

The following precaution should be taken while soldering*

. (se always an iron plated copper core tip for soldering iron.

7. 1lightly for the tip with a cut file when it is cold.

3. (se a wet sponge to wipe out dirt from the tip before soldering instead of

asking the iron.

:. Tighten the tip screw if necessary before iron is connected to power supply.

2. Clean component lead and copper pad before soldering.

-. )pply solder between component leads, ?.C.=. pattern and tip of soldering

iron.

/. Iron should be kept in contact with the joint for 73 seconds only instead of

keeping for %ery long or %ery small time.

. (se optimum uantity of solder

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3.# WORKING:

The robot, is controlled by a mobile phone that makes call to the mobile phone attached to

the robot in the course of the call, if any button is pressed control corresponding to the button

pressed is heard at the other end of the call. This tone is called dual tone multi freuency

tome #DTM!$ robot recei%es this DTM! tone with the help of phone stacked in the robot

The recei%ed tone is processed by the atmega- microcontroller with the help of DTM!

decoder MT/0 the decoder decodes the DTM! tone in to its eui%alent binary digit and

this binary number is send to the microcontroller, the microcontroller is preprogrammed to


the motors for forward or backward motion or a turn.

The mobile that makes a call to the mobile phone stacked in the robot acts as a remote. 1o

this simple robotic project does not reuire the construction of recei%er and transmitter units.

DTM! signaling is used for telephone signaling o%er the line in the %oice freuency band to

the call switching center. The %ersion of DTM! used for telephone dialing is known as touch

tone .

DTM! assigns a specific freuency #consisting of two separate tones$ to each key s that it

can easily be identified by the electronic circuit. The signal generated by the DTM! encoder

is the direct algeabric submission, in real time of the amplitudes of two sine#cosine$ wa%es of

different freuencies, i.e. ,pressing 2 will send a tone made by adding 33-h5 and //0h5 to

the other end of the mobile. In order to control the robot, you need to make a call to the cell

phone attached to the robot #through head phone$ from any phone, which sends DTM! tunes

on pressing the numeric buttons. The cell phone in the robot is kept in Oauto answer@ mode.

#If the mobile does not ha%e the auto answering facility, recei%e the call by O


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robot is kept in Hauto answerH mode.# if the mobile does not ha%e the auto answering facility

,recei%e the call by H


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4.

RESULT

AND

DISCUSSION

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4.1 RESULT:

The project we ha%e undertaken has helped us gain a better perspecti%e on %arious aspects

related to our course of study as well as practical knowledge of electronic euipment@s and

communication. 'e became familiar with software analysis, designing, implementation,

testing and maintenance concerned with our project. The e6tensi%e capabilities of this

system are what make it so interesting. !rom the con%enience of a simple cell phone, a user

is able to control and monitor %irtually any electrical de%ices. This makes it possible for users

to rest assured that their belongings are secure and that the tele%ision and other electrical

appliances was not left running when they left the house to just list a few of the many uses of

this system. The end product will ha%e a simplistic design making it easy for users to interact

with. This will be essential because of the wide range of technical knowledge that

homeowners ha%e. +1M =ased Control 1ystem.

'hen constructing any robot, one major mechanical constraint is the

number )n actualsi5e, singleside ?C= layout for cellphone operated land ro%er !ig. 2*

Component layout of motors being used. Nou can ha%e either a twowheel dri%e or a four

wheel dri%e. Though fourwheel dri%e is more comple6 than twowheel dri%e, it pro%ides

more torue and good control. Twowheel dri%e, on the other hand, is %ery easy to construct.

Top %iew of a fourwheeldri%en land ro%er is shown in !ig. 3. The chassis used in this model

is a 0]cm7 sheet made up of para6. Motors are fi6ed to the bottomof this

sheet and the circuit is affi6ed firmly on top of the

sheet. ) cellphone is also mounted on the sheet as shown in the picture. In the fourwheel

dri%e system, the two motors on a side are controlled in parallel. 1o a single 7>3D dri%er IC

can dri%e the ro%er. !or this robot, beads affi6ed with glue act as support

wheels. In the process of reali5ing this project, the construction was initially carried out on a

breadboard to allow for checking and to ascertain that it is functioning effecti%ely. )ll

irregularities were checked then tested and found to ha%e a satisfactory output. The

component were then remo%ed and transferred to a Bero board strip and soldered into place

and all discontinuous point were cut out to a%oid shortcircuiting.

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4.2 DISCUSSION

'hen constructing any robot, one major mechanical constraint is the

number an actualsi5e, singleside ?C= layout for cellphoneoperated land ro%er. Component

layout of motors being used. Nou can ha%e either a twowheel dri%e or a fourwheel dri%e.

Though fourwheel dri%e is more comple6 than twowheel dri%e, it pro%ides more torue and

good control. Twowheel dri%e, on the other hand, is %ery easy to construct. Top %iew of a

fourwheeldri%en land ro%er

4.2.1 T)8,- ; P(


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4.2.2.2 C=*-)-8 P()/+0,- :

I; sensor used should be sensiti%e. =efore using in the circuit it should be tested with a

multimeter.

. I.C should not be heated much while solderingE too much heat can destroy the

I.C. !or safety and ease of replacement, the use of I.C socket is suggested.

7. 'hile placing the I.C pin no should be made sure at right hole.

3.


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4.2.3. ADVANTAGES:

. Cellphoneoperatedrobotic landro%er includes.

7. 'ireless controlling pro%isioning and sur%eillance system.

3. 3+technologybased %ehicle na%igation.

:. imitless operational range based on the network of the cellphone.

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4.2.4 DISADVANTAGES:

. The cost as the cellphone billing is high.

7. Mobile batteries discharge * the discharging problem associated with the

batteries as the batteries loss charge due to uick discharge because the load is high.

3. )daptability* the system is not adaptable to all cellphones, but the ones with the headset

attached can only be used.

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AND

FUTURE SCOPE

5.1 CONCLUSION:

The project we ha%e undertaken has helped us gain a better perspecti%e on %arious aspects

related to our course of study as well as practical knowledge of electronic euipment@s and

communication. 'e became familiar with software analysis, designing, implementation,

testing and maintenance concerned with our project. The e6tensi%e capabilities of this

system are what make it so interesting. !rom the con%enience of a simple cell phone, a user

is able to control and monitor %irtually any electrical de%ices. This makes it possible for users

to rest assured that their belongings are secure and that the tele%ision and other electrical

appliances was not left running when they left the house to just list a few of the many uses of

this system. The end product will ha%e a simplistic design making it easy for users to interact

with. This will be essential because of the wide range of technical knowledge that

homeowners ha%e. +1M =ased Control 1ystem.

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5.2 FUTURE SCOPE:

1. IR S)-8(8:

I; sensors can be used to automatically detect & a%oid obstacles if the robot goes beyond

line of sight. This a%oids damage to the %ehicle if we are maneu%ering it from a distant place.

2. P+88( P()/,-:

?roject can be modified in order to password protect the robot so that it can be operated only

if correct password is entered. Aither cell phone should be password protected or necessary

modification should be made in the assembly language code. This introduces conditioned

access & increases security to a great e6tent.

3. A+(= P-) D,+)(:

=y replacing DTM! Decoder IC CM/0 by a HDTM! Transcei%er IC@ CM0, DTM!

tones can be generated from the robot. 1o, a project called H)larm ?hone diallerH can be built

which will generate necessary alarms for something that is desired to be monitored #usually

by triggering a relay$. !or e6ample, a high water alarm, low temperature alarm, opening of

back window, garage door, etc.

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'hen the system is acti%ated it will call a number of programmed numbers to let the user

know the alarm has been acti%ated. This would be great to get alerts of alarm conditions from

home when user is at work.

4. A,- + C+=)(+:

If the current project is interfaced with a camera #e.g. a 'ebcam$ robot can be dri%en beyond

lineofsight & range becomes practically unlimited as +1M networks ha%e a %ery large

range.This land ro%er can be further impro%ed to ser%e specific purposes.It

reuires four controls to roam around. The remaining eight controls can be configured to

ser%e other purposes,with some modifications in the source program.

REFERENCES

. The 02 Microcontroller and Ambedded 1ystems^ =y Muhammad )li Ma5idi and

Lanice +illispie Ma5idi. ?earson Aducation.

7. 1. Chemishkian, =uilding smart ser%ices for smart home^, ?roceedings of IAAA

:thInternational 'orkshop on 8etworked )ppliances, 70 pp* 7 2 77:.s

3. ;. 1harma, P. Pumar, and 1. Bi, DTM! =ased ;emote Control 1ystem, IAAA

International Conference ICIT 700-, pp. 730733, December 700-.

:. ;.C. uo, T.M. Chen, and C.C. Nih, Intelligent autonomous mobile robot control

through the Internet,^IAAA International 1ymposium I1IA 7000, %ol. , pp. -,

December 7000

2. +. )rangurenss, . 8o5al, ). =la5ue5, and L. )rias, ";emote control of sensors and

actuators by +1M", IAAA 7007 7th )nnual Conference of the Industrial Alectronics

1ociety IAC>/ IAAA international conference on

robotics & control systems .

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/. Intelligent control >> proceedings IAAA international symposium on robotics &

control systems.

. Amerging trends in robotics and communication technologies, 700 International

conference on ;obotics & control systems.

APPENDICES

The programming codes for this model are done in the programming language C and are

gi%en below.%oid main#%oid$

R

unsigned int k, hEDD;C0600E

DD;D0!!E

while #$ R

k _?I8CEhk & 060!E

switch #h$

Rcase 0607* if I? is 0607

R

ie !orward?


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breakE

V

case 060:*R

eft turn

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` ?eripheral !eatures \ Two bit TimerCounters with 1eparate ?rescalers and Compare

Modes \

Cell Phone Operated Robot Report

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Transcript of Cell Phone Operated Robot Report