Introduction:

The project objective is to design a robot which uses the command from the system to move

forward, backward, left and in right direction. We’ll control the robot with the help of personal

computer and the direction of movement in forward, backward, left and right direction is controlled

by using wireless cam .The circuit uses 8051 microcontroller and transmission-reception is done by

FM transmitter and receiver.

The most basic requirement of the present era is speed and utilization of each second. In order to accomplish the fact that a person can’t be at two places at a single instance. It provides efficient and prompt service whenever required.

Keeping in mind the above stated views, we have developed a project entitled as “Surveillance Machine”. Basically, surveillance means a closed observation taken by a police or else. Our machine is able to access in those areas where trespassing of a human being is not in practice and where we are unable to do so. With the help of this machine, we can analyze the objects far from us with the use of its functional features (Video and Audio transmitter). Further, this machine can be applied in various areas.

The focus of the project was to design and build a wireless telemetry retrieval communication system that effectively communicates pertinent data. This document describes the functionality of our project. It provides detailed specifications used with detailed circuit information.

We had considered a lot of engineering aspects while designing this project. We considered mechanical, electrical and electronics aspects while designing the vehicle. As far as these different fields of engineering are concerned, we had taken care of all those minute features that could be incorporated within budget.

The vehicle is controlled by a small hand-held remote control with four switches (up, down, right, left) through RADIO FREQUENCY that can make the vehicle go forward, backward and turning combinations.

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Chapter 1

PURPOSE OF SELECTION OF PROJECT

SELECTION CRITERIA FOR TOOLS USED

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PURPOSE OF SELECTION OF PROJECT

A technical student should have all theoretical and practical knowledge concerning his field of curriculum.

Hence, to check the acquired knowledge, there is a provision to make group project. This establishes our practical way of thinking. Thus to achieve above standard we are introducing a project named:

PC Based Wireless Controlled Robot

This project is optimized flexible synthesized and implemented for further enhancement. Our project is an effort toward going growing and emerging field.

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SELECTION CRITERIA FOR TOOLS USED

89C52 microcontroller: - It is an ISP; in this we can done programming directly at the time of running.

Crystal oscillator:- A crystal oscillator is an electronic circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. This frequency is commonly used to keep track of time (as in quartz wristwatches), to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers. The most common type of piezoelectric resonator used is the quartz crystal, so oscillator circuits designed around them were called "crystal oscillators".

Voltage regulator:- A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level.

It may use an electromechanical mechanism, or passive or active electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.

Rectifier: - This is used in our project according to its need.

Filters:- This is used because it reduces the noise which occurs or eliminate the noise which is raised.

Bridge rectifier:- it is used in our project because for conversion of alternating current (AC) input into direct pulsating current (DC) output.

D. C. Motor:- A DC motor is designed to run on DC electric power. The modern DC motor was invented by accident in 1873.

By far the most common DC motor types are the brushed and brushless types, which use internal and external commutation respectively to create an oscillating AC current from the DC source

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Chapter 2

TOOLS USED

(BRIEF DISCRIPTION)

Component Used:

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1. Microcontroller AT89C52

2. Max-232

3. SM6136

4. SM6135

5. Voltage Regulator 7805

6. Transformer

7. Bridge Rectifier

8. Crystal Oscillator

9. Wireless Camera

10. L.E.D

11. Capacitor

12. Pull up Resistor

13. Resistor

14. Transistor

15. Inductor

16. Antenna

17. D.C. Motor

18. Battery

19. Berg Strip

20. DB-9 Connector

1. Microcontroller AT89C52:

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Introduction

Introduced in 1980, the 8052 is the original member of MCS-51 family & is the core for all

MCS-51 devices.

The MCS-51 micro controller family has a number of members. Members in this family differ

mainly in the amount of on-chip memories and IO capabilities.

Feature Quantity

ROM 8K bytes

RAM 256 bytes

Timer 3

I/O pins 32

Interrupt Sources 8

Table No.1 Features of the 89C52

Registers of 89C52

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Figure No.1 REGISTER OF AT89C52

Block Diagram

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Figure No.2 AT89C52

2. MAX 232:

The MAX232 & MAX232A

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The MAX232 from Maxim was the first IC which in one package contains the necessary drivers (two) and receivers (also two), to adapt the RS-232 signal voltage levels to TTL logic. It became popular, because it just needs one voltage (+5V) and generates the necessary RS-232 voltage levels (approx. -10V and +10V) internally. This greatly simplified the design of circuitry. Circuitry designers no longer need to design and build a power supply with three voltages (e.g. -12V, +5V, and +12V), but could just provide one +5V power supply, e.g. with the help of a simple 78x05 voltage converter.

The MAX232 has a successor, the MAX232A. The ICs are almost identical, however, the MAX232A is much more often used (and easier to get) than the original MAX232, and the MAX232A only needs external capacitors 1/10th the capacity of what the original MAX232 needs.

It should be noted that the MAX232(A) is just a driver/receiver. It does not generate the necessary RS-232 sequence of marks and spaces with the right timing, it does not decode the RS-232 signal, it does not provide a serial/parallel conversion. All it does is to convert signal voltage levels. Generating serial data with the right timing and decoding serial data has to be done by additional circuitry, e.g. by a 16550 UART or one of these small micro controllers (e.g. Atmel AVR, Microchip PIC) getting more and more popular.

The original manufacturer (and now some clone manufacturers, too) offers a large series of similar ICs, with different numbers of receivers and drivers, voltages, built-in or external capacitors, etc. E.g. The MAX232 and MAX232A need external capacitors for the internal voltage pump, while the MAX233 has these capacitors built-in. The MAX233 is also between three and ten times more expensive in electronic shops than the MAX232A because of its internal capacitors. It is also more difficult to get the MAX233 than the garden variety MAX232A.

A similar IC, the MAX3232 is nowadays available for low-power 3V logic.

Figure3 MAX232 PIN LAYOUT

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MAX232 to RS232 DB9 Connection as a DCE

MAX232 Pin Nbr. MAX232 Pin Name Signal Voltage DB9 Pin

7 T2out CTS RS-232 7

8 R2in RTS RS-232 8

9 R2out RTS TTL n/a

10 T2in CTS TTL n/a

11 T1in TX TTL n/a

12 R1out RX TTL n/a

13 R1in TX RS-232 3

14 T1out RX RS-232 2

15 GND GND 0 5

TABLE2. MAX232 to RS232 DB9 Connection

3. SM6136:

It is a special type of IC which is used as the transmitter IC in the toy car. This IC works as transmitter in our project which is used to transmit the movement signals such as forward, backward, left and right to the receiver section mounted on the car. This IC consists of 14 pins in which 4 are specially designed for the motion of the car. This IC also contains some special functions which are used to transmit the desired signal to the receiver IC. This IC uses FM modulation to transmit the signal on to the receiver section. In FM modulation process a crystal oscillator is being used of 49 MHz. This section is used to generate the required carrier

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frequency for FM modulation. Using this frequency only the signal is transmitted to the receiver section. For different movement of the vehicle there are different frequencies being used. At the receiver side when the signal are received they are demodulated by generating a same carrier of the same frequency at the receiver side.

4. SM6135:

This is the IC used at the receiver section of the toy car. This IC works as the receiver IC which is same as the transmitter IC 6136 but it has got some special functions. It has 4 pins specially dedicated for the movement functions and 4 pins for detecting the signals named as VO1, VO2, VI1, VI2. These 4 pins first detects the desired signals and then sends to the corresponding pins such as forward, backward, left, right. At the receiver end the same carrier frequency is used to demodulate the signal as it was used to modulate the signal at the transmitter section. At the receiver end, signal is demodulated and by the help of this IC, motors are driven accordingly. We are using two motors, one for forward and backward motion and another for left and right motion. The left and right motion are controlled using gears.

5. Voltage regulator (LM7805):

Voltage Regulator (regulator), usually having three legs, converts varying input voltage and produces a constant regulated output voltage. They are available in a variety of outputs. The most common part numbers start with the numbers 78 or 79 and finish with two digits indicating the output voltage. The number 78 represents positive voltage and 79 negative one. The 78XX series of voltage regulators are designed for positive input. And the 79XX series is designed for negative input.

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Examples: 5V DC Regulator Name: LM7805 or MC7805 -5V DC Regulator Name: LM7905 or MC7905 6V DC Regulator Name: LM7806 or MC7806 -9V DC Regulator Name: LM7909 or MC7909 The LM78XX series typically has the ability to drive current up to 1A. For application requirements up to 150mA, 78LXX can be used. As mentioned above, the component has three legs: Input leg which can hold up to 36VDC Common leg (GND) and an output leg with the regulator's voltage. For maximum voltage regulation, adding a capacitor in parallel between the common leg and the output is usually recommended. Typically a 0.1MF capacitor is used. This eliminates any high frequency AC voltage that could otherwise combine with the output voltage. See below circuit diagram which represents a typical use of a voltage regulator.

FIGURE4. LM7805

As a general rule the input voltage should be limited to 2 to 3 volts above the output voltage. The LM78XX series can handle up to 36 volts input, be advised that the power difference between the input and output appears as heat.

6. Transformer:

A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors — the transformer's coils or "windings". Except for air-core transformers, the conductors are commonly wound around a single iron-rich core, or around separate but magnetically-coupled cores. A varying current in the first or "primary" winding creates a varying magnetic field in the core (or cores) of the transformer. This varying magnetic field induces a varying electromotive force (EMF) or "voltage" in the "secondary" winding. This effect is called mutual induction.

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If a load is connected to the secondary, an electric current will flow in the secondary winding and electrical energy will flow from the primary circuit through the transformer to the load. In an ideal transformer, the induced voltage in the secondary winding (VS) is in proportion to the primary voltage (VP), and is given by the ratio of the number of turns in the secondary to the number of turns in the primary as follows:

By appropriate selection of the ratio of turns, a transformer thus allows an alternating current (AC) voltage to be "stepped up" by making NS greater than NP, or "stepped down" by making NS less than NP.

Transformers come in a range of sizes from a thumbnail-sized coupling transformer hidden inside a stage microphone to huge units weighing hundreds of tons used to interconnect portions of national power grids. All operate with the same basic principles, although the range of designs is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in nearly all electronic devices designed for household ("mains") voltage. Transformers are essential for high voltage power transmission, which makes long distance transmission economically practical.

Step down transformer, the newly designed transformer especially for the customers around the world. Step down transformer comes in different types and they are also referred has step up transformer. The appearance of step down transformer will be in a winding model and they come in two pieces line models. Step down transformer are produced with high durability, resistance and also with standard features. The main purpose of produced step down transformer is to satisfy the requirements of the customer around the world.

7. Bridge Rect i f ier:

A bridge rectifier makes use of four diodes in a bridge arrangement to achieve full-wave rectification. This is a widely used configuration, both with individual diodes wired as shown and with single component bridges where the diode bridge is wired internally.

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FIGURE5.Bridge Rectifier

Bridge rectifier is an electronic component which converts an input AC current into a DC current as an output. Electronic devices, and particularly portable electronic devices such as portable computers, cellular phones, and personal digital assistants (PDAs) typically make use of alternating current to direct current adapters (AC adapters) either as a direct source of power, or as a source of power to charge on-board batteries. Bridge rectifiers are used to rectify current output from alternative current sources, such as an alternating current generator. Three-phase bridge rectifiers have been provided for rectifying a three-phase alternating current to convert it to a corresponding direct current. The rectifiers generally comprise a three-phase rectifier circuit including six three-phase bridge-connected diodes and a smoothing capacitor connected between DC output terminals of the rectifier circuit. The six pulse bridge phase controlled rectifier is a widely used type of solid state power converter which is used in industry for converting a three phase ac input voltage to a variable dc voltage. The six pulse bridge phase controlled rectifier uses six thyristors as controllable power devices. Bridge rectifiers for motor vehicle alternators generally include two metal parts used as heat sinks that are electrically insulated from each other.

8. Crystal Oscillator:

A crystal oscillator is an electronic circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. This frequency is commonly used to keep track of time (as in quartz wristwatches), to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers. The most common type of piezoelectric resonator used is the quartz crystal, so oscillator circuits designed around them were called "crystal oscillators".

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A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions.

Almost any object made of an elastic material could be used like a crystal, with appropriate transducers, since all objects have natural r e sonan t frequencies of vibration. For example, s t e e l is very elastic and has a high speed of sound. It was often used in mechanical filters before quartz. The resonant frequency depends on size, shape, e l a s t i c i t y , and the speed of sound in the material. High-frequency crystals are typically cut in the shape of a simple, rectangular plate. Low-frequency crystals, such as those used in digital watches, are typically cut in the shape of a t un ing fo rk . For applications not needing very precise timing, a low-cost c e r amic r e sona to r is often used in place of a quartz crystal.

When a crystal of qua r t z is properly cut and mounted, it can be made to distort in an electric field by applying a vo l t age to an e l e c t rode near or on the crystal. This property is known as p i ezoe l ec t r i c i t y . When the field is removed, the quartz will generate an electric field as it returns to its previous shape, and this can generate a voltage. The result is that a quartz crystal behaves like a circuit composed of an i nduc to r , c apac i t o r and r e s i s t o r , with a precise resonant frequency.

Quartz has the further advantage that its elastic constants and its size change in such a way that the frequency dependence on temperature can be very low. The specific characteristics will depend on the mode of vibration and the angle at which the quartz is cut (relative to its crystallographic axes).

Therefore, the resonant frequency of the plate, which depends on its size, will not change much, either. This means that a quartz clock, filter or oscillator will remain accurate. For critical applications the quartz oscillator is mounted in a temperature-controlled container, called a c ry s t a l oven , and can also be mounted on shock absorbers to prevent perturbation by external mechanical vibrations.

Quartz timing crystals are manufactured for frequencies from a few tens of k i l ohe r t z to tens of megahe r t z . More than two billion (2×109) crystals are manufactured annually. Most are small devices for consumer devices such as wr i s twa t ches , c l ocks , r ad io s , compu te r s , and ce l l phones . Quartz crystals are also found inside test and measurement equipment, such as counters, s i gna l gene ra to r s , and o sc i l l o scopes .

9. Wireless Camera:

Wireless video camera with transmitter and receiver. it is an video surveillance for security. it is as small as cigarette case. one can hide it easily. camera is as tiny as pinhole camera with excellent video, clarity like handy cam. hi resolution - color wireless cordless camera. just fix it to your TV or vcr and record the thing. easy start process. excellent resolution. can gather sensitive information. Can use to keep a watch on your baby (i. e. Make sure the baby is undisturbed and asleep ). To transmit live video footage of your parties. to keep a watch on

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who is coming and going. Can be used for spying. It comes in loose pack. No manual is given along with it.Kit includes:

1. Camera

2. Transmitter

3. Input/output cable

4. Adapter

5. Battery6.Antenna

Features:

1. Wireless transmission and reception

2. Send and Receive pictures through walls with high resolution

3. Small and Light Weight

4. High Sensitivity

5. Easy 1-Minute Installation

Functionality:

1. Visitor Identifying

2. Home Security

3. Camera vision for RC Planes, Boats, Subs & Cars

4. High Portability Camera Solution

5. Moving Detection

6. Entry Detection

10. L.E.D:

A light-emitting diode (LED) is an e l e c t ron i c light source. The LED was first invented in Russia in the 1920s, and introduced in America as a practical electronic component in 1962. Oleg Vladimirovich Losev was a radio technician who noticed that diodes used in radio receivers emitted light when current was passed through them. In 1927, he published details in a Russian journal of the first ever LED.

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All early devices emitted low-intensity red light, but modern LEDs are available across the visible, ultraviolet and infra red wavelengths, with very high brightness.

LEDs are based on the s emiconduc to r d iode . When the diode is forward biased (switched on), e l e c t rons are able to r e combine with ho l e s and energy is released in the form of light. This effect is called e l e c t ro luminescence and the co lo r of the light is determined by the ene rgy gap of the semiconductor. The LED is usually small in area (less than 1 mm2) with integrated optical components to shape its radiation pattern and assist in reflection.

LEDs present many advan t ages over traditional light sources including lower ene rgy consumpt ion , longer l i f e t ime , improved robustness, smaller size and faster switching. However, they are relatively expensive and require more precise cu r r en t and hea t managemen t than traditional light sources.

Applications of LEDs are diverse. They are used as low-energy indicators but also for replacements for traditional light sources in general l i gh t i ng and au tomot ive l i gh t i ng . The compact size of LEDs has allowed new text and video displays and sensors to be developed, while their high switching rates are useful in communications technology.

Like a normal d iode , the LED consists of a chip of semi conducting material impregnated, or doped , with impurities to create a p -n j unc t i on . As in other diodes, current flows easily from the p-side, or anode , to the n-side, or c a thode , but not in the reverse direction. Charge-carriers—elec t rons and ho l e s —flow into the junction from e l ec t rodes with different vo l t age s . When an electron meets a hole, it falls into a lower ene rgy l eve l , and releases ene rgy in the form of a pho ton .

The wave l eng th of the light emitted, and therefore its color, depends on the band gap energy of the materials forming the p-n junction. In s i l i con or ge rman ium diodes, the electrons and holes recombine by a non-radiative transition which produces no optical emission, because these are i nd i r ec t band gap materials. The materials used for the LED have a d i r e c t b a n d g a p with energies corresponding to near-infrared, visible or near-ultraviolet light.

LED development began with infrared and red devices made with ga l l i um a r sen ide . Advances in ma t e r i a l s s c i ence have made possible the production of devices with ever-shorter wave l eng ths , producing light in a variety of colors.

ColorWavelength

[nm]Voltage [V] Semiconductor Material

Infrared λ > 760 ΔV < 1.9Gallium arsenide (GaAs)Aluminium gallium arsenide (AlGaAs)

Red 610 < λ < 760 1.63 < ΔV < 2.03

Aluminium gallium arsenide (AlGaAs)Gallium arsenide phosphide (GaAsP)

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Aluminium gallium indium phosphide (AlGaInP)Gallium(III) phosphide (GaP)

Orange 590 < λ < 6102.03 < ΔV < 2.10

Gallium arsenide phosphide (GaAsP)Aluminium gallium indium phosphide (AlGaInP)Gallium(III) phosphide (GaP)

Yellow 570 < λ < 5902.10 < ΔV < 2.18

Gallium arsenide phosphide (GaAsP)Aluminium gallium indium phosphide (AlGaInP)Gallium(III) phosphide (GaP)

Green 500 < λ < 570 2.18 < ΔV < 4.0

Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN)Gallium(III) phosphide (GaP)Aluminium gallium indium phosphide (AlGaInP)Aluminium gallium phosphide (AlGaP)

Blue 450 < λ < 500 2.48 < ΔV < 3.7

Zinc selenide (ZnSe)Indium gallium nitride (InGaN)Silicon carbide (SiC) as substrateSilicon (Si) as substrate — (under development)

Violet 400 < λ < 450 2.76 < ΔV < 4.0 Indium gallium nitride (InGaN)

TABLE3. LEDs Color & Their Wave Length

11. Capacitor:

A capacitor or condenser is a pa s s ive e l e c t ron i c componen t consisting of a pair of conduc to r s separated by a d i e l e c t r i c . When a vo l t age po t en t i a l d i f f e r ence exists between the conductors, an e l e c t r i c f i e l d is present in the dielectric. This field stores ene rgy and produces a mechanical force between the plates. The effect is greatest between wide, flat, parallel, narrowly separated conductors.

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An ideal capacitor is characterized by a single constant value, c apac i t ance , which is measured in f a r ads . This is the ratio of the e l e c t r i c cha rge on each conductor to the potential difference between them. In practice, the dielectric between the plates passes a small amount of l e akage cu r r en t . The conductors and leads introduce an equ iva l en t s e r i e s r e s i s t ance and the dielectric has an electric field strength limit resulting in a b r eakdown vo l t age .

The properties of capacitors in a circuit may determine the resonant frequency and qua l i t y f a c to r of a r e sonan t c i r cu i t , power dissipation and operating frequency in a d ig i t a l l og i c circuit, energy capacity in a high-power system, and many other important system characteristics.

A capacitor consists of two conductors separated by a non-conductive region.[4] The non-conductive substance is called the dielectric medium, although this may also mean a vacuum or a semiconductor depletion region chemically identical to the conductors. A capacitor is assumed to be self-contained and isolated, with no net electric charge and no influence from an external electric field. The conductors thus contain equal and opposite charges on their facing surfaces,[5] and the dielectric contains an electric field. The capacitor is a reasonably general model for electric fields within electric circuits.

An ideal capacitor is wholly characterized by a constant capacitance C, defined as the ratio of charge ±Q on each conductor to the voltage V between them:[4]

Sometimes charge buildup affects the mechanics of the capacitor, causing the capacitance to vary. In this case, capacitance is defined in terms of incremental changes:

In SI units, a capacitance of one farad means that one coulomb of charge on each conductor causes a voltage of one volt across the device.[6]

12. Pull-up resistors:

Pull-down resistors are used to hold the input to a zero (low) value when no other component is driving the input. They are used less often than pull-up resistors. Pull-down resistors can safely be used with CMOS logic gates because the inputs are voltage-controlled. TTL logic inputs that are left un-connected inherently float high, thus they require a much lower valued pullPull Up Resistor:

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Pull-up r e s i s t o r s are used in electronic l og i c c i r cu i t s to ensure that inputs to logic systems settle at expected logic levels if external devices are disconnected. Pull-up resistors may also be used at the interface between two different types of logic devices, possibly operating at different power supply voltages.

The idea of a pull-up resistor is that it weakly "pulls" the voltage of the wire it's connected to towards 5V (or whatever voltage represents a logic "high"). However, the resistor is intentionally weak (high-resistance) enough that, if something else strongly pulls the wire toward 0V, the wire will go to 0V. An example of something that would strongly pull a-down resistor to force the input low. This also consumes more current. For that reason, pull-up resistors are preferred in TTL circuits.

In b ipo l a r logic families operating at 5 VDC, a typical pull-up resistor value will be 1000–5000 Ω , based on the requirement to provide the required logic level current over the full operating range of temperature and supply voltage. For CMOS and MOS logic, much higher values of resistor can be used, several thousand to a million ohms, since the required leakage current at a logic input is small.

FIGURE6. Pull-Up Resistor

13. Resis tor :

A resistor is a two-terminal electronic component designed to oppose an electric current by producing a voltage drop between its terminals in proportion to the current, that is, in accordance with Ohm's law:

V = IR

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Resistors are used as part of electrical networks and electronic circuits. They are extremely commonplace in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel/chrome).

The primary characteristics of resistors are their resistance and the power they can dissipate. Other characteristics include temperature coefficient, noise, and inductance. Less well-known is critical resistance, the value below which power dissipation limits the maximum permitted current flow, and above which the limit is applied voltage. Critical resistance depends upon the materials constituting the resistor as well as its physical dimensions; it's determined by design.

Resistors can be integrated into hybrid and printed circuits, as well as integrated circuits. Size, and position of leads (or terminals) are relevant to equipment designers; resistors must be physically large enough not to overheat when dissipating their power.

Nearly always, the resistance value is of interest. The value of a resistor can be measured with an ohmmete r , which may be one function of a mu l t ime t e r . Usually, probes on the ends of test leads connect to the resistor.

Measuring low-value resistors, such as fractional-ohm resistors, with acceptable accuracy requires four-terminal connections. One pair of terminals applies a known, calibrated current to the resistor, while the other pair senses the voltage drop across the resistor. Some laboratory test instruments have spring-loaded pairs of contacts, with neighboring contacts electrically isolated from each other. Better digital multimeters have four terminals on their panels, generally used with special test leads. These comprise four wires in all, and have special test clips with jaws insulated from each other.

One jaw provides the measuring current, while the other senses the voltage drop.

ost axial resistors use a pattern of colored stripes to indicate resistance. Su r f ace -moun t resistors are marked numerically, if they are big enough to permit marking; more-recent small sizes are impractical to mark. Cases are usually tan, brown, blue, or green, though other colors are occasionally found such as dark red or dark gray.

Early 20th century resistors, essentially uninsulated, were dipped in paint to cover their entire body for color coding. A second color of paint was applied to one end of the element, and a color dot (or band) in the middle provided the third digit.

The rule was "body, tip, dot", providing two significant digits for value and the decimal multiplier, in that sequence. Default tolerance was ±20%. Closer-tolerance resistors had silver (±10%) or gold-colored (±5%) paint on the other end.

Each color corresponds to a certain digit, progressing from darker to lighter colors, as shown in the chart below.

Color 1st band 2nd band 3rd band (multiplier) 4th band (tolerance) Temp. Coefficient

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Black 0 0 ×100

Brown 1 1 ×101 ±1% (F) 100 ppm

Red 2 2 ×102 ±2% (G) 50 ppm

Orange 3 3 ×103 15 ppm

Yellow 4 4 ×104 25 ppm

Green 5 5 ×105 ±0.5% (D)

Blue 6 6 ×106 ±0.25% (C)

Violet 7 7 ×107 ±0.1% (B)

Gray 8 8 ×108 ±0.05% (A)

White 9 9 ×109

Gold ×10-1 ±5% (J)

Silver ×10-2 ±10% (K)

None ±20% (M)

TABLE4. Color Coding For Resistance

14. Transistor:

In electronics, a transistor is a semiconductor device commonly used to amplify or switch electronic signals. A transistor is made of a solid piece of a semiconductor material, with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals. Because the controlled (output) power can be much larger than the controlling (input) power, the transistor provides amplification of a signal. The transistor is the fundamental building block of modern electronic devices, and is used in radio, telephone, computer and other electronic systems. Some transistors are packaged individually but most are found in integrated circuits.

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The essential usefulness of a transistor comes from its ability to use a small signal applied between one pair of its terminals to control a much larger signal at another pair of terminals. This property is called ga in . A transistor can control its output in proportion to the input signal, that is, can act as an amp l i f i e r . Or, the transistor can be used to turn current on or off in a circuit like an electrically controlled sw i t ch , where the amount of current is determined by other circuit elements.

The two types of transistors have slight differences in how they are used in a circuit. A bipolar transistor has terminals labelled base, collector and emitter. A small current at base terminal (that is, flowing from the base to the emitter) can control or switch a much larger current between collector and emitter terminals. For a field-effect transistor, the terminals are labelled gate, source, and drain, and a voltage at the gate can control a current between source and drain.

The image to the right represents a typical bipolar transistor in a circuit. Charge will flow between emitter and collector terminals depending on the current in the base. Since internally the base and emitter connections behave like a semiconductor diode, a voltage drop develops between base and emitter while the base current exists. The size of this voltage depends on the material the transistor is made from, and is referred to as VBE.

15. Inductor:

An inductor or reactor is a pa s s ive e l e c t r i c a l componen t that can store ene rgy in a magne t i c f i e l d created by the e l e c t r i c cu r r en t passing through it. An inductor's ability to store magnetic energy is measured by its i nduc t ance , in units of hen r i e s . Typically an inductor is a conducting wire shaped as a coil, the loops help create a strong magnetic field inside the coil due to Fa raday ' s l aw o f i nduc t i on . Inductors are one of the basic electronic components used in electronics where current and voltage change with time, due to the ability of inductors to delay and reshape alternating currents.

An "ideal inductor" has inductance, but no r e s i s t ance or c apac i t ance , and does not dissipate or radiate energy. A real inductor may be partially modeled by a combination of inductance, resistance (due to the resistively of the wire and losses in core material), and capacitance. At some frequency, usually higher than the working frequency, some real

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inductors behave as a r e sonan t c i r cu i t (due to its s e l f c apac i t ance ). At some frequency the capacitive component of impedance gets dominant. In addition to dissipating energy in the resistance of the wire, magnetic core inductors may dissipate energy in the core due to hys t e r e s i s , and at high currents (b i a s cu r r en t s ) show gradual departure from ideal behavior due to non l i nea r i t y caused by magne t i c s a tu r a t i on .Additionally, real-world inductors work as an t ennas , radiating a part of energy processed into surrounding space and circuits, and accepting electromagnetic emissions from other circuit, taking part in e l e c t romagne t i c i n t e r f e r ence . Real-world inductor applications deal heavily with "parasitic" parameters, while the "inductance" may be of minor significance.

Inductance (L) (measured in henries) is an effect resulting from the magnetic field that forms around a current-carrying conductor that tends to resist changes in the current. Electric current through the conductor creates a magnetic flux proportional to the current. A change in this current creates a change in magnetic flux that, in turn, by Faraday's law generates an electromotive force (EMF) that acts to oppose this change in current. Inductance is a measure of the amount of EMF generated for a unit change in current. The number of loops, the size of each loop, and the material it is wrapped around all affect the inductance

16. Antenna:

An antenna (or aerial) is a t r ansduce r designed to t r ansmi t or r e ce ive e l e c t romagne t i c waves . In other words, antennas convert electromagnetic waves into electrical currents and vice versa. Antennas are used in systems such as r ad io and t e l ev i s i on broadcasting, point-to-point radio communication, w i r e l e s s LAN , r ada r , and space exp lo ra t i on . Antennas usually work in air or ou t e r space , but can also be operated under water or even through soil and rock at certain frequencies for short distances.

Physically, an antenna is an arrangement of conduc to r s that generate a radiating e l e c t romagne t i c f i e l d in response to an applied alternating voltage and the associated alternating e l e c t r i c cu r r en t , or can be placed in an electromagnetic field so that the field will i nduce an alternating current in the antenna and a voltage between its terminals. Some antenna devices (pa r abo l i c an t enna , Horn An tenna ) just adapt the free space to another type of antenna.

25

The words antenna (plural: antennas) and aerial are used interchangeably; but usually a rigid metallic structure is termed an antenna and a wire format is called an aerial. In the Un i t ed K ingdom and other B r i t i sh Eng l i sh speaking areas the term aerial is more common, even for rigid types. The noun aerial is occasionally written with a diaresis mark — aërial — in recognition of the original spelling of the adjective aërial from which the noun is derived.

The origin of the word antenna relative to wireless apparatus is attributed to Gug l i e lmo Marcon i . In 1895, while testing early radio apparatus in the Swi s s A lps at Sa lvan , Swi t ze r l and in the Mon t B l anc region, Marconi experimented with early wireless equipment. A 2.5 meter long pole, along which was carried a wire, was used as a radiating and receiving aerial element. In Italian a tent pole is known as l'antenna centrale, and the pole with a wire alongside it used as an aerial was simply called l'antenna. Until then wireless radiating transmitting and receiving elements were known simply as aerials or terminals. Marconi's use of the word antenna (I t a l i an for pole) would become a popular term for what today is uniformly known as the antenna.

17. D.C. Motor:

An electric motor is a device using e l ec t r i c a l ene rgy to produce mechan i ca l ene rgy , nearly always by the interaction of magnetic fields and current-carrying conductors. The reverse process, that of using mechanical energy to produce electrical energy, is accomplished by a gene ra to r or dynamo . T rac t i on mo to r s used on vehicles often perform both tasks.

Electric motors are found in myriad uses such as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and computer disk drives, among many other applications. Electric motors may be operated by direct current from a ba t t e ry in a portable device or motor vehicle, or from alternating current from a central electrical distribution grid. The smallest motors may be found in electric wristwatches. Medium-size motors of highly standardized dimensions and characteristics provide convenient mechanical power for industrial uses. The very largest electric motors are used for propulsion of large ships, and for such purposes as pipeline compressors, with ratings in the thousands of k i l owa t t s . Electric motors may be classified by the source of electric power, by their internal construction, and by application.

26

The principle

The principle of conversion of electrical energy into mechanical energy by electromagnetic means was demonstrated by the British scientist Michae l Fa raday in 1821 and consisted of a free-hanging wire dipping into a pool of me rcu ry . A permanent magne t was placed in the middle of the pool of mercury. When a cu r r en t was passed through the wire, the wire rotated around the magnet, showing that the current gave rise to a circular magnetic field around the wire. This motor is often demonstrated in school physics classes, but b r i ne (salt water) is sometimes used in place of the toxic mercury. This is the simplest form of a class of electric motors called homopo la r mo to r s . A later refinement is the Ba r low ' s Whee l .

A p p l i c a t i o n s

Computer-controlled stepper motors are one of the most versatile forms of pos i t i on ing sy s t ems . They are typically digitally controlled as part of an open l oop system, and are simpler and more rugged than c lo sed l oop s e rvo systems.

Industrial applications are in high speed pick and place equipment and multi-axis machine CNC machines often directly driving l e ad s c r ews or ba l l s c r ews . In the field of lasers and optics they are frequently used in precision positioning equipment such as l i nea r a c tua to r s , l i nea r s t age s , r o t a t i on s t age s , gon iome te r s , and mi r ro r moun t s . Other uses are in packaging machinery, and positioning of valve pilot stages for fluid control systems.

Commercially, stepper motors are used in f l oppy d i sk d r i ve s , f l a t bed s canne r s , compu te r p r i n t e r s , p lo t t e r s and many more devices

18. Battery:

In electronics, a battery or voltaic cell is a combination of one or more e l e c t rochemica l Ga lvan i c c e l l s which store chemica l ene rgy . These cells create a voltage difference between the terminals of the battery. When an external electrical circuit is connected to the battery, then the battery drives an electric current through the circuit and electrical work is done. Since the invention of the first Vo l t a i c p i l e in 1800 by A le s sand ro Vo l t a , the battery has become a common power source for many household and industrial applications, and is now a multi-billion do l l a r industry.

The name "battery" was coined by Ben j amin F rank l i n for an arrangement of multiple Laden j a r s (an early type of c apac i t o r ) after a cannon. Common usage includes a single electrical cell in the definition.

A battery is a device that converts chemical energy directly to electrical energy. It consists of one or more voltaic cells; each voltaic cell consists of two ha l f c e l l s connected in series by a conductive electrolyte containing anions and cations. One half-cell includes electrolyte and the electrode to which an ions (negatively-charged ions) migrate, i.e. the anode or negative

27

electrode; the other half-cell includes electrolyte and the electrode to which ca t i ons (positively-charged ions) migrate, i.e. the c a thode or positive electrode. In the r edox reaction that powers the battery, reduction (addition of electrons) occurs to cations at the cathode, while oxidation (removal of electrons) occurs to anions at the anode. The electrodes do not touch each other but are electrically connected by the electrolyte, which can be either solid or liquid.] Many cells use two half-cells with different electrolytes. In that case each half-cell is enclosed in a container, and a separator that is porous to ions but not the bulk of the electrolytes prevents mixing.

Each half cell has an electromotive force (or emf), determined by its ability to drive electric current from the interior to the exterior of the cell. The net emf of the battery is the difference between the emfs of its half-cells, as first recognized by Volta. ] Thus, if the electrodes have

emfs and , then the net emf is ; in other words, the net emf is difference between the r educ t i on po t en t i a l s of the ha l f - r e ac t i ons .

The electrical driving force or across the terminals of a battery is known as the terminal voltage (difference) and is measured in vo l t s . The terminal voltage of a battery that is neither charging nor discharging is called the open -c i r cu i t vo l t age and equals the emf of the battery. Because of internal resistance, the terminal voltage of a battery that is discharging is smaller in magnitude than the open-circuit voltage and the terminal voltage of a battery that is charging exceeds the open-circuit voltage. An ideal battery has negligible internal resistance, so it would maintain a constant terminal voltage of until exhausted, then dropping to zero. If such a battery maintained 1.5 volts and stored a charge of one Cou lomb then on complete discharge it would perform 1.5 Jou l e of work. In actual batteries, the internal resistance increases under discharge, and the open circuit voltage also decreases under discharge.

19. Berg Strip:

It is used to connect two or more boards.

it is a type of connector which consist of wires use for connections.

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20. DB-9 Connector:

In telecommunications, RS-232 (Recommended Standard 232) is a standard for serial binary data signals connecting between a DTE (Data Terminal Equipment) and a DCE (Data Circuit-terminating Equipment). It is commonly used in computer serial ports. A similar ITU-T standard is V.24.

RS-232 devices may be classified as Data Terminal Equipment (DTE) or Data Communications Equipment (DCE); this defines at each device which wires will be sending and receiving each signal. The standard recommended but did not make mandatory the D-submin i a tu r e 25 pin connector. In general and according to the standard, terminals and computers have male connectors with DTE pin functions, and modems have female connectors with DCE pin functions. Other devices may have any combination of connector gender and pin definitions. Many terminals were manufactured with female terminals but were sold with a

29

cable with male connectors at each end; the terminal with its cable satisfied the recommendations in the standard.

Presence of a 25 pin D-sub connector does not necessarily indicate an RS-232-C compliant interface. For example, on the original IBM PC, a male D-sub was an RS-232-C DTE port (with a non-standard cu r r en t l oop interface on reserved pins), but the female D-sub connector was used for a parallel Cen t ron i c s printer port. Some pe r sona l compu te r s put non-standard voltages or signals on some pins of their serial ports.

The standard specifies 20 different signal connections. Since most devices use only a few signals, smaller connectors can often be used. For example, the 9 pin DE-9 connector was used by most IBM-compatible PCs since the IBM PC AT, and has been standardized as T IA-574 . More recently, modu la r connec to r s have been used. Most common are 8P8C connectors. Standard E IA/TIA 561 specifies a pin assignment, but the "Yost Serial Device Wiring Standard" invented by Dave Yost (and popularized by the Un ix Sys t em Admin i s t r a t i on Handbook ) is common on Un ix computers and newer devices from C i sco Sys t ems . Many devices don't use either of these standards. 10P10C connectors can be found on some devices as well. D ig i t a l Equ ipmen t Corpo ra t i on defined their own DECconnec t connection system which was based on the Mod i f i ed Modu la r J ack connector. This is a 6 pin modular j a ck where the key is offset from the center position. As with the Yost standard, DECconnect uses a symmetrical pin layout which enables the direct connection between two DTEs. Another common connector is the

Chapter 4

30

PROJECT

(PCB LAYOUT & DETAILS)

BLOCK DIAGRAM:

31

FIGURE7.Block Diagram

Circuit Diagram

MICROCONTROLLER

(8051)

Power Supply

FM Transmitter

FM Receiver

PC Interface

Decoding Circuit Wireless camera Monitor

32

FIGURE8.Circuit Diagram

33

FIGURE9. FM Transmitter

34

FIGURE10. FM Receiver

35

PCB Layout:

FIGURE11.PCB Layout 1

FIGURE12. PCB Layout 2

36

Working:

The circuit consists of a step down transformer which converts the incoming 230 v to 12v. The transformer used is a center tapped transformer.

This 12 v is given to a bridge rectifier which converts the incoming AC voltage to a DC voltage. This DC voltage is fed to 7805 IC. The function of 7805 IC is to convert the incoming voltage to 5 Volts, whatever is there incoming voltage this IC converts into 5 Volts.

The PC Generates four coded signal that are transmitted through the FM Modulation. The Microcontroller gets the 4 signal from the PC and encodes then gives the Signal to FM transmitter. The carrier is generated and is of 30MHz. The transmitter transmits the signal and FM receiver receives and then demodulates the signal and according to the code the motor moves in 4 directions.

The microcontroller has been programmed to move the vehicle in desired direction. When keys are pressed on the keypad of the computer, it is transmitted to the microcontroller. As computer transmits the signal at +12V levels and -12V level and microcontroller understand the signal at +5Vand 0V so an IC MAX232 is used. The MAX232 is an integrated circuit that converts signals from an RS-232 serial port to signals suitable for use in TTL compatible digital logic circuits. The MAX232 is a dual driver/receiver and typically convert the RX, TX, CTS and RTS signals. The microcontroller is programmed according to the motion of the car. So as the keys are pressed PC transmits the signal through serial communication to microcontroller.

In our project the microcontroller we are using is 89S52 of which only 4 pins of port 2 are used i.e. (P2.4,P2.5,P2.6 & P2.7).These 4 pins are connected to the IC SM6136 of transmitter circuit which are used to control the car motion.

37

Chapter 5

RESULT

38

RESULT

The project is working properly, it travels in straight path and if obstacle comes in its path than, it diverts from its original path and after taking an action it regain its original path. It can be used at a place where more accuracy is required, without any manual help. And by which we can reduce the time of work and also our expenditure towards our goal. It is more accurate than manual help to our target.

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Chapter 6

CONCLUSION

FUTURE SCOPE

40

Conclusion:

There are many regions which are inaccessible for human being. The vehicular robot to be

constructed would be able to enter such regions and send the required data. A camera would

send back picture to the remote computer from the working field and this will enable the user

to analyze the working environment to gauge the risk factor involved for the particular task.

Another application for the robot could be its capability to be used for surveillance.

Well it is a system that contains sensors, control systems, manipulators, power supplies

and software all working together to perform a task. Designing, building, programming and

testing a robot is a combination of physics, mechanical engineering, electrical engineering,

structural engineering, mathematics and computing. In some cases biology, medicine,

chemistry might also be involved.

The type of robots that you will encounter most frequently are robots that do work that is

too dangerous, boring, onerous, or just plain nasty. Most of the robots in the world are of this

type. They can be found in auto, medical, manufacturing and space industries. In fact, there are

over a million of these types of robots working for us today.

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Future Scope:

1. The main future aspect of our project would be to include an IR sensor so that the

device becomes smart enough that it can see a wall or any obstacle in its path, thereby,

deciding the next movement.

2. We can also introduce telemetric control as well as the control through Internet so that

the system can be controlled through any part of the world where Internet is provided.

3. Further, improving the field view of camera, we can provide a wireless controlled

stepper motor, which will enable us to increase the view area to be analyzed, that too in

all directions.

4. This system can be used in shops and other places where security is required.

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APPENDIX

43

APPENDIX A

Microcontroller programming:

include <REGX52.H>

#include"serial.h"

#include"delay.h"

sbit f= P2^4;

sbit b= P2^5;

sbit l= P2^6;

sbit r= P2^7;

char rec1,rec2;

char q;

void main()

f=b=l=r=1;

TMOD = 0x20; //timer 1 8 bit auto reload

TH1 = 0xfd; // 9600 baud rate

SCON = 0x50; // transmit control register

SBUF=0;

for(q=0;q<20;q++)

transmit('*');

44

transmit('S');

transmit('T');

transmit('A');

transmit('R');

transmit('T');

transmit('*');

while(1)

rec1= recieve();

if(rec1=='5')

f=1; // f= right

b=1; // b= left

l=1; // l= forward

r=1; // r= back

transmit('S');

transmit('T');

transmit('O');

transmit('P');

transmit(0x0D);

45

if(rec1=='8')

f=0;

b=1;

l=1;

r=1;

transmit('F');

transmit('O');

transmit('R');

transmit('W');

transmit(0x0D);

if(rec1=='2')

f=1;

b=0;

l=1;

r=1;

transmit('B');

transmit('A');

transmit('C');

46

transmit('K');

transmit(0x0D);

if(rec1=='4')

f=1;

b=1;

l=0;

r=1;

transmit('L');

transmit('E');

transmit('F');

transmit('T');

transmit(0x0D);

if(rec1=='6')

f=1;

b=1;

l=1;

r=0;

47

transmit('R');

transmit('I');

transmit('G');

transmit('H');

transmit('T');

transmit(0x0D);

if(rec1=='7')

f=0;

b=1;

l=0;

r=1;

transmit('F');

transmit('W');

transmit('-');

transmit('L');

transmit('E');

transmit('F');

transmit(0x0D);

if(rec1=='9')

48

f=0;

b=1;

l=1;

r=0;

transmit('F');

transmit('W');

transmit('-');

transmit('R');

transmit('I');

transmit('G');

transmit(0x0D);

if(rec1=='1')

f=1;

b=0;

l=0;

r=1;

49

transmit('B');

transmit('A');

transmit('-');

transmit('L');

transmit('E');

transmit('F');

transmit(0x0D);

if(rec1=='3')

f=1;

b=0;

l=1;

r=0;

transmit('B');

transmit('A');

transmit('-');

transmit('R');

transmit('I');

transmit('G');

transmit(0x0D);

50

Receive Function Definition:-

Unsigned char recieve()

char x;

RI=0;

while(RI==0);

x=SBUF;

RI=1;

return(x);

51

APPENDIX B

List of Components

52

S. No. Name/ Brief Description

Voltage and Current Rating

Cost of Component

1 7805 5 V 15 Rs.

2 89s52 5 V 40 Rs.

4 Transformer 12 V 35 Rs.

5 Camera - 3000 Rs.

6 Battery 5 V 25 Rs.

7 Diode - 1 Rs.

8 Capacitor 470 µF, 10µF 5 Rs.

9 D. C. Motor 12 V 80 Rs.

10 Resistor 4.7 KΩ, 10 KΩ

1Rs.

11 Transistor PC547 2 Rs.

12 Crystal Oscillator1

11.0592 M Hz 5 Rs.

13 Land rover - 250 Rs.

Table5. List of components

53

6. Applications:

1. Bomb Disposal.

2. Navigation purpose.

3. In military field application.

4. In Aerospace Electronics.

5. Pick and Place.

6. Car surveillance system

54

7.Limitation:

1. Range is limited, the range of FM transmitter and receiver is 40-50 meters.

2. Low battery backup.

55

APPENDIX C

DATA SHEETS

56

APPENDIX D

LIST OF TABLES

S. No. Table No. Table Name Page No.

1 1 Features of 89c52 7

2 2 MAX232 to RS232 DB9 Connection

11

3 3 LEDs Color & Their Wave Length

19

4 4 Color Coding For Resistance

23

5 5 List of components 54

57

APPENDIX E

List of Figures

S. No. Figure No. Figure Name Page No.

1 1 REGISTER OF AT89C52

08

2 2 AT89C52 09

3 3 MAX232 PIN LAYOUT

11

4 4 LM 7805 13

5 5 Bridge rectifier 15

6 6 Pull up resistor 21

7 7 Block diagram 32

8 8 Circuit diagram 33

9 9 FM transmitter 34

10 10 FM receiver 35

11 11 PCB layout1 36

12 12 PCB layout2 36

58

Bibliography

www.google.com

Electronics for you (www.electronicsforu.com)

www.howstuffwork.com

www.efymag.com

www.datasheet4u.com

www.wikipedia.org

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