Project File

MAJOR PROJECT REPORT ON “Automated Parking System” Submitted as part of course curriculum for Diploma In Computer engineering PUNJAB STATE BOARD OF TECHNICAL EDUCATION CHANDIGARH , 160014

Under the guidance of

Submitted by:

Miss. Puneet Gupta

Gagandeep Kaur (110326207165) Navkiran Kaur (110326207182) Sheenu Garg (110326207203)

DEPARTMENT OF COMPUTER ENGINEERING, GOVT. POLYTECHNIC COLLEGE FOR GIRLS, S.S.T NAGAR, PATIALA

Acknowledgement No matter how much enterprising and entrepreneurial one’s thinking is, yet nobody can do everything all by himself without help and guidance. It is inhumane if the concerned person’s assistance goes without appreciation and thanks. Many individuals have contributed for the completion of this project. For their invaluable guidance, comments and suggestions, we wish to express our deep sense of indebtedness and sincerest gratitude to our project guide “Miss Puneet Gupta” for her invaluable guidance and constructive criticism throughout this dissertation. She has displayed unique tolerance and understanding at every step of progress and encouraged us incessantly. We deem it our privilege to have carried out our dissertation work under her able guidance. The supervision and support that she gave truly helped the progression and smoothness of the training period. The co-operation is much indeed appreciated. We express our sincere thanks to “Mr. Narinder Singh Dhindsa”H.O.D Computer Science engineering for accepting our application and giving us an opportunity to work on the project. As a final personal note, we our grateful to our parents, who are inspirational to us in their understanding, patience and constant encouragement. (SIGNATURE) Gagandeep Kaur (110326207165) Navkiran Kaur (110326207182) Sheenu Garg (110326207203)

Table of contents

1. Abstract

2. Features 3. Block diagram 4. Block diagram description:•

Proximity sensor

•

Comparator

•

Microcontroller

•

Current amplifier

•

Component list

5 Working 6 Software tools

Introduction to Project As we all know vehicles are increasing day by day because of the increase in the standard of living of the people. In every family there is at least one car and in some of the cases there is one car per member. As nobody can control the increasing no. of vehicles the traffic in public places is bound to increase and is increasing very rapidly. Thus, parking is a very big problem these days. Although most of the places are having private parking owned by the builders who have hired

no. of employees for

collecting charges for parking per time basis yet there is always a problem of putting a check on the no. of vehicles already present inside. In order to grapple with the same automated car parking is the best feasible solution. In this we keep a check on the no. of vehicles entering and leaving the parking by appropriate sensors and display the same on find. This enables the person in the car to know whether there is place inside or not. This will help him in deciding where to park, will save much petrol and will make their visit worthwhile. This will also help in saving their valuable time.

Features of Project 1.

Fully automatic gate control

2. Up and Down counter 3. Every slot contains one sensor 4. The gate doesn’t open if parking is already full. 5. The gate will get open if somebody wants to go outside.

2.

Block Diagram

Block Diagram Description Proximity sensor A proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. A proximity sensor often emits electromagnetic or electrostatic field, or a beam of electromagnetic radiation (infrared, for instance), and looks for changes in the field or return signal. The object being sensed is often referred to as the proximity sensor's target. Different proximity sensor targets demand different sensors. For example, a capacitive or photoelectric sensor might be suitable for a plastic target; an inductive proximity sensor requires a metal target. The maximum distance that this sensor can detect is defined "nominal range". Some sensors have adjustments of the nominal range or means to report a graduated detection distance. Proximity sensors can have a high reliability and long functional life because of the absence of mechanical parts and lack of physical contact between sensor and the sensed object. Comparator In electronics, a comparator is a device which compares two voltages or currents and switches its output to indicate which is larger. A dedicated voltage comparator will generally be faster than a general-purpose opamp pressed into service as a comparator. A dedicated voltage comparator may also contain additional features such as an accurate, internal voltage reference, an adjustable hysteresis and a clock gated input. Microcontroller A microcontroller (also MCU or µC) is a functional computer system-on-a-chip. It contains a processor core, memory, and programmable input\output peripherals. Microcontrollers include an integrated CPU, memory (a small amount of RAM, program memory, or both) and peripherals capable of input and output. It emphasizes high integration, in contrast to a microprocessor which only contains a CPU (the kind used in a PC). In addition to the usual arithmetic and logic elements of a general purpose microprocessor, the microcontroller integrates additional elements such as read-write memory for data storage, read-only memory for program storage, Flash memory for permanent data storage, peripherals, and input/output interfaces. At clock speeds of as little as 32KHz, microcontrollers often operate at very low speed compared to microprocessors, but this is adequate for typical applications. They consume relatively little power (milliwatts or even

microwatts), and will generally have the ability to retain functionality while waiting for an event such as a button press or interrupt. Power consumption while sleeping (CPU clock and peripherals disabled) may be just nanowatts, making them ideal for low power and long lasting battery applications. Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, remote controls, office machines, appliances, power tools, and toys. By reducing the size, cost, and power consumption compared to a design using a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to electronically control many more processes. Current Amplifier Below figure presents one solution specific to the 8051 microcontrollers. In this very case, Darlington transistor is used to activate relays because of its high current gain. This is not in accordance with “rules”, but it is necessary in case of logic one activation since the current is then very low (pin acts as input)!

Component list

Sr.no

Component

specification

Quantity

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

Microcontroller IR LED Photo Sensor Current Amplifier Stepper Motor Crystal Opamp Transformer Led Diode Capacitor Pcb

89s51 5mm 5 mm Uln2803 12V 12mhz LM324 12-0-12 5mm 1n4007 2200mfd/25 v -

1 10 10 1 1 1 10 1 1 2 1 -

Working of Project There are two sensors which are connected to sense the vehicle at the entry-point of the parking. These sensors inform the microcontroller about the number of vehicles entering into the parking area. This enables the microcontroller to keep the record of the number of vehicles and appropriately release the control signal to indicate to the driver of the vehicle whether there is any more space in the parking area or not. If the space is there, then the microcontroller releases the control signal to open up the gates using stepper motor. There are various slot sensors which will keep the record of the status of slots whether available or not. If the slot is available, then they display the no. of the corresponding slot so that the driver of the vehicle becomes aware of the available slot, thus avoiding the traffic jams within and outside the parking slot. However, if the slot is not available they will indicate it and will not give signal to the stepper motor to open up the gates at the entry.

Software tools Orcad for circuit designing .We first make schematic in it.This in turn creates layout of PCB. Keil for compiling. Microcontroller understands hex files. But as hex files are very complicated therefore we make use of the software keil. Programming in keil makes use of C or Assembly language which is easily programmable. Keil on its own converts these files to hex files. Proload After the formation of hex file we need to insert this hex file into the micro controller so that it executes the program written in the keil. For this purpose we make use of Proload. Soldering Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, the filler metal having a relatively low melting point. Soft soldering is characterized by the melting point of the filler metal, which is below 400 °C (800 °F). The filler metal used in the process is called solder. Soldering is distinguished from brazing by use of a lower melting-temperature filler metal; it is distinguished from welding by the base metals not being melted during the joining process. In a soldering process, heat is applied to the parts to be joined, causing the solder to melt and be drawn into the joint by capillary action and to bond to the materials to be joined by wetting action. After the metal cools, the resulting joints are not as strong as the base metal, but have adequate strength, electrical conductivity, and water-tightness for many uses. Soldering is an ancient technique mentioned in the Bible and there is evidence that it was employed up to 5000 years ago in Mesopotamia.

Soldering Tools The only tools that are essential to solder are a soldering iron and some solder. There are, however, lots of soldering accessories available (see soldering accessories for more information). Different soldering jobs will need different tools, and different temperatures too. For circuit board work you will need a finer tip, a lower temperature and finer grade solder. You may also want to use a magnifying glass. Audio connectors such as XLR's will require a larger tip, higher temperature and thicker solder. Clamps and holders are also handy when soldering audio cables. Soldering Irons

There are several things to consider when choosing a soldering iron.  Wattage  adjustable or fixed temperature  power source (electric or gas)  portable or bench use I do not recommend soldering guns, as these have no temperature control and can get too hot. This can result in damage to circuit boards, melt cable insulation, and even damage connectors. Wattage It is important to realise that higher wattage does not necessarily mean hotter soldering iron. Higher wattage irons just have more power available to cope with bigger joints. A low wattage iron may not keep its temperature on a big joint, as it can loose heat faster than it can reheat itself. Therefore, smaller joints such as circuit boards require a lesser wattage iron - around 15-30 watts will be fine. Audio connectors need something bigger - I recommend 40 watts at least.

Temperature

There are a lot of cheap, low watt irons with no temperature control available. Most of these are fine for basic soldering, but if you are going to be doing a lot you may want to consider a variable temperature soldering iron. Some of these simply have a boost button on the handle, which is useful with larger joints, others have a thermostatic control so you can vary the heat of the tip. If you have a temperature controlled iron you should start at about 315-345°C (600-650°F). You may want to increase this however - I prefer about 700-750°F. Use a temperature that will allow you to complete a joint in 1 to 3 seconds. Power

Most soldering irons are mains powered - either 110/230v AC, or benchtop soldering stations which transform down to low voltage DC. Also available are battery and gas powered. These are great for the toolbox, but you'll want a plug in one for your bench. Gas soldering irons loose their heat in windy outside conditions more easily that a good high wattage mains powered iron. Portability Most cheaper soldering irons will need to plug into the mains. This is fine a lot of the time, but if there is no mains socket around, you will need another solution. Gas and battery soldering irons are the answer here. They are totally portable and can be taken and used almost anywhere. They may not be as efficient at heating as a good high wattage iron, but they can get you out of a lot of hassle at times.

If you have a bench setup, you should consider using a soldering station. These usually have a soldering iron and desoldering iron with heatproof stands, variable heat, and a place for a cleaning pad. A good solder station will be reliable, accurate with its temperature, and with a range of tips handy it can perform any soldering task you attempt with it. Solder

The most commonly used type of solder is rosin core. The rosin is flux, which cleans as you solder. The other type of solder is acid core and unless you are experienced at soldering, you should stick to rosin core solder. Acid core solder can be tricky, and better avoided for the beginner. Rosin core solder comes in three main types - 50/50, 60/40 and 63/37. These numbers represent the amount of tin and lead are present in the solder,as shown below. Solder Type 50/50 60/40 63/37

% Tin 50 60 63

% Lead 50 40 37

Melting Temp (°F) 425 371 361

Any general purpose rosin core solder will be fine.

Soldering Accessories Soldering Iron Tips

Try to use the right size tip whenever you can. Smaller wires and circuit boards require small fine tips, and mic cable onto an XLR would need a larger tip. You can get pointed tips, or flat tipped ones (sometimes called 'spade tips'). If you have a solder station with a desolderer, you will also want a range of desoldering tips and cleaners. Soldering Iron Stands

These are handy to use if you are doing several or more joints. It is a heat resistant cradle for your iron to sit in, so you don't have to lie it down on the bench while it is hot. It really is essential if you are planning to do a lot of bench soldering as it is only a matter of time before you burn something (probably your elbow resting on the hot tip) if you don't use one. Clamps

I strongly recommend clamps of some sort. Trying to hold your soldering iron, the solder, and the wire is tricky enough, but when you have to hold the connector as well it is almost impossible. The are however, adjustable clamps that can be manipulated to hold both the connector and the wire in place so you still have two

free hands to apply the heat and the solder. These are cheap items, and I know mine have paid for themselves many times over. Magnifying glass

If you are doing work on PCBs (printed circuit boards) you may need to get a magnifying glass. This will help you see the tracks on the PCB, and unless you have exceptional sight, small chip resistors are pretty difficult to solder on well without a magnifying glass. Once again, they are not expensive, and some clamps come with one that can mount on the clamp stand. Solder Wick

Solder wick is a mesh the you lie on a joint and heat. When it heats up it also melts the solder which is drawn out of the joint. It is usually used for cleaning up solder from tracks on a circuit board, but you will need a solder sucker to clean out the holes in the circuit board. Place the wick on the solder you want to remove then put your soldering iron on top of the wick. The wick will heat up, then the solder will melt and flow away from the joint and into wick. Solder Suckers

If you don't have a solder station with desolderer, and you work on PCB's, you are going to need one of these before too long. They are spring loaded and suck the melted solder out of the joint. They are a bit tricky to use, as you have to melt the

solder with your iron, then quickly position the solder sucker over the melted solder and release the spring to suck up the solder. I find solder wick to be easier to use and more effective. Fume Extractors

Solder fumes are poisonous. A fume extractor will suck the fumes (smoke) into itself and filter it. An absolute must for your health if you are setting up a soldering bench.

Preparation Step 1: Preparation

If you are preparing the cable for a connector, I strongly suggest you put any connector parts on now (the screw on part of an XLR, or casing of a 1/4" jack for example). Get into the habit of sliding these on before you start on the cable, or else you can bet it won't be long before you finish soldering your connector only to discover you forgot to put the connector casing on, and have to start all over again. Once you have all the connector parts on that you need, you will need to strip your cable. This means removing the insulation from the end of the wire and exposing the copper core. You can either use a wire stripper, side cutters, or a knife to do this.

The obvious tool to choose to strip a wire would be......a wire stripper. There are many types of wire stripper, and most of them work the same. You simply put the wire in, and squeeze it and pull the end bit off. It will cut to a preset depth, and if you have chosen the right depth it will cut the insulation off perfectly. It is possible to choose the wrong depth and cut too deeply, or too shallow, but they are very easy to use. On the other hand, some people (myself included) prefer to use a knife or side cutters. I use side cutters for small cable and a Stanley knife for bigger cables...and although I have a couple of wire strippers, I haven't used them for years. This may seem odd, but I've got my side cutters and knife with me anyway, and they do the job fine.

If you are using side cutters (as shown here), position them about 10mm (1/2 inch) from the end, and gently squeeze the cutters into the insulation to pierce it, but not far enough to cut the copper strands of the core. Open the cutters slightly so you can turn the wire and pierce the rest of the insulation. You may have to do this a few times to cut through all of the insulation, but it is better to cut too shallow and have to turn and cut again rather than cut the core and have to start again. Now you should be able to slide the insulation off with your cutters, or pull it off with your fingers. This may sound a tedious method, but in no time at all you will be able to do it in two cuts and a flick of the cutters. I won't explain how I use a knife to do larger cable, as I'd hate someone to slice a finger or thumb open following my instructions. Using a sharp blade like that certainly does have it's risks, so stick with wire cutters or side cutters if you are at all unsure.

If your connector has been used before, make sure you remove any remnants of wire and solder from the contacts. Do this by putting the tip of your soldering iron into the hole and flicking the solder out when it has melted. Common Sense Alert! Please be careful when you flick melted solder...flick it away from you.

Tinning Step 2: Tinning

Whatever it is you are soldering, you should 'tin' both contacts before you attempt to solder them. This coats or fills the wires or connector contacts with solder so you can easily melt them together. To tin a wire, apply the tip of your iron to the wire for a second or two, then apply the solder to the wire. The solder should flow freely onto the wire and coat it (if it's stranded wire the solder should flow into it, and fill the wire). You may need to snip the end off afterwards, particularly if you have put a little too much solder on and it has formed a little ball at the end of the wire.

Be careful not to overheat the wire, as the insulation will start to melt. On cheaper cable the insulation can 'shrink back' if heated too much, and expose more copper core that you intended. You can cut the wire back after you have tinned it, but it's best simply not to over heat it. The larger the copper core, the longer it will take to heat up enough to draw the solder in, so use a higher temperature soldering iron for larger cables if you can.

To tin a contact on an audio XLR connector, hold the iron on the outside of the the contact for a second or two, then apply the solder into the cavity of the contact. Once again, the solder should flow freely and fill the contact. Connectors such as jacks have contacts that are just holes in a flat part of the connector. To tin these you put your iron on it, and apply the solder to where the iron is touching. The solder should flow and cover the hole. Once you have tinned both parts, you are ready to solder them together.

Soldering Step 3: Soldering

This step can often be the easiest when soldering audio cables. You simply need to place your soldering iron onto the contact to melt the solder. When the solder in the contact melts, slide the wire into the contact. Remove the iron and hold the wire still while the solder solidifies again. You will see the solder 'set' as it goes hard.

This should all take around 1-3 seconds.  A good solder joint will be smooth and shiny.  If the joint is dull and crinkly, the wire probably moved during soldering.  If you have taken too long it will have have solder spikes. If it does not go so well, you may find the insulation has melted, or there is too much stripped wire showing. If this is the case, you should desolder the joint and start again.

Cleaning Your Soldering Iron You should clean your tip after each use. There are many cleaning solutions and the cheapest (and some say best) is a damp sponge. Just rub the soldering iron tip on it after each solder.

Another option is to use tip cleaner. This comes in a little pot that you push the tip into. This works well if your tip hasn't been cleaned for a while. It does create a lot of smoke, so it is better not to let the tip get so dirty that you need to use tip cleaner.

Some solder stations come with a little pad at the base of the holder. If you have one of these, you should get into the habit of wiping the tip on the pad each time you apply solder with it.

If you need to clean solder off a circuit board, solder wick is what you need. You place the wick on the joint or track you want to clean up, and apply your soldering iron on top. The solder melts and is drawn into the wick. If there is a lot of solder the wick will fill up, so gently pull the wick through the joint and your iron, and the solder will flow into it as it passes.

Transformers A "transformer" takes one voltage and changes it into another. What is a transformer, and why should I care? A "transformer" changes one voltage to another. This attribute is useful in many ways. A transformer doesn't change power levels. If you put 100 Watts into a transformer, 100 Watts come out the other end. [Actually, there are minor losses in the transformer because nothing in the real world is 100% perfect. But transformers come pretty darn close; perhaps 95% efficient.] A transformer is made from two coils of wire close to each other (sometimes wrapped around an iron or ferrite "core"). Power is fed into one coil (the "primary"), which creates a magnetic field. The magnetic field causes current to flow in the other coil (the "secondary"). Note that this doesn't work for direct current (DC): the incoming voltage needs to change over time - alternating current (AC) or pulsed DC.

Iron core The number of times the wires are wrapped around the core ("turns") is very important and determines how the transformer changes the voltage.  If the primary has fewer turns than the secondary, you have a step-up transformer that increases the voltage.  If the primary has more turns than the secondary, you have a step-down

transformer that reduces the voltage.  If the primary has the same number of turns as the secondary, the outgoing voltage will be the same as what comes in. This is the case for an isolation transformer.  In certain exceptional cases, one large coil of wire can serve as both primary and secondary. This is the case with variable auto-transformers and xenon strobe trigger transformers.

Types of transformers In general, transformers are used for two purposes: signal matching and power supplies. Power Transformers Power transformers are used to convert from one voltage to another, at significant power levels.

Step-up transformers

A "step-up transformer" allows a device that requires a high voltage power supply to operate from a lower voltage source. The transformer takes in the low voltage at a high current and puts out the high voltage at a low current. Examples:  You are a Swiss visiting the U.S.A., and want to operate your 220VAC shaver off of the available 110 VAC.  The CRT display tube of your computer monitor requires thousands of volts, but must run off of 220 VAC from the wall.

Step-down transformers

A "step-down transformer" allows a device that requires a low voltage power supply to operate from a higher voltage. The transformer takes in the high voltage at a low current and puts out a low voltage at a high current. Examples:  Your Mailbu-brand landscape lights run on 12VAC, but you plug them into the 220 VAC line.  Your doorbell doesn't need batteries. It runs on 220 VAC, converted to 12VAC. In many cases, step-down transformers take the form of wall warts.

Isolation transformers

An "isolation transformer" does not raise or lower a voltage; whatever voltage comes in is what goes out. An isolation transformer prevents current from flowing directly from one side to the other. This usually serves as a safety device to prevent electrocution.

Rectifier What is a Rectifier? A rectifier changes alternating current into direct current. This process is called rectification. The three main types of rectifier are the half-wave, full-wave, and bridge. A rectifier is the opposite of an inverter, which changes direct current into alternating current. Half-Wave Rectifier

The simplest type is the half-wave rectifier, which can be made with just one diode. When the voltage of the alternating current is positive, the diode becomes forwardbiased and current flows through it. When the voltage is negative, the diode is reverse-biased and the current stops. Full-Wave Rectifier

The full-wave rectifier is essentially two half-wave rectifiers, and can be made with two diodes and an earthed center tap on the transformer. The positive voltage half of the cycle flows through one diode, and the negative half flows through the other. The center tap allows the circuit to be completed because current can not flow through the other diode. The result is still a pulsating direct current but with just over half the input peak voltage, and double the frequency.

Bridge Rectifier

The bridge rectifier, also called a diode bridge, consists of four diodes connected together in a square. Two diodes are connected at their anodes, and the other two are connected at their cathodes. These form the rectified output terminals. The remaining ends are joined to form two input terminals. It it usually packaged as one component with four terminals. The bridge rectifier allows for full-wave rectification without the need for an earthed center tap on the transformer.

Smoothing

Even the bridge rectifier has some variation in it's output voltage, so a filter is required to smooth out this ripple. A capacitor connected across the output

terminals acts as a basic filter by storing energy during the peak voltage, and releasing it when the voltage falls. This removes most of the ripple but does not result in a steady voltage. A choke and second capacitor are usually added to further smooth the ripple. Rectifier Uses Rectifiers are used mostly in power adapters and alternators to convert alternating current to direct current. They are also used in radios to demodulate signals from the antenna. 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. 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.

Lm7805

Heat sink

IR Receiver and Transmitter IR LED emits infrared radiation. This radiation illuminates the surface in front of LED. Surface reflects the infrared light. Depending on reflectivity of the surface, amount of light reflected varies. This reflected light is made incident on reverse biased IR sensor.

When photons are incident on reverse biased junction of this diode, electron-hole pairs are generated, which results in reverse leakage current. Amount of electronhole pairs generated depends on intensity of incident IR radiation. More intense radiation results in more reverse leakage current. This current can be passed through a resistor so as to get proportional voltage. Thus as intensity of incident rays varies, voltage across resistor will vary accordingly. This voltage can then be given to OPAMP based comparator.Output of the comparator can be read by uC. Alternatively, you can use on-chip ADC in AVR microcontroller to measure this voltage and perform comparison in software. IR LED and IR sensor : IR LED is used as a source of infrared rays. It comes in two packages 3mm or 5mm. 3mm is better as it is requires less space. IR sensor is nothing but a diode, which is

sensitive for infrared radiation. http://elecrom.files.wordpress.com/2008/02/cropirsensors.jpg This infrared transmitter and receiver is called as IR TX-RX pair. It can be obtained from any decent electronics component shop and costs less than 10Rs. Following snap shows 3mm and 5mm IR pairs. Colour of IR transmitter and receiver is different. However you may come across

pairs which appear exactly same or even has opposite colours than shown in above pic and it is not possible to distinguish between TX and RX visually. In case you will have to take help of multimeter to distinguish between them. Here is how you can distinguish between IR TX-RX using DMM :  Connect cathode of one LED to +ve terminal of DMM  Connect anode of the same LED to common terminal of DMM (means connect LED such that It gets reverse biased by DMM )  Set DMM to measure resistance upto 2M Ohm.  Check the reading.  Repeat above procedure with second LED.  In above process, when you get the reading of the few hundred Kilo Ohms on DMM, then it indicated that LED that you are testing is IR sensor. In case of IR transmitter DMM will not show any reading. Following snap shows typical DMM reading obtained when IR receiver is connected to it as mentioned above. Second snap shows how sensor’s resistance increases when it is covered by a finger. Note that, these are just illustrative figures and they will depend upon sensor as well as DMM that you are using.

While buying an IR sensor, make sure that its reverse resistance in ambient light is below 1000K. If it is more than this value, then it will not be able to generate sufficient voltage across external resistor and hence will be less sensitive to small variation in incident light.

The circuit diagram : Circuit diagram for IR sensor module is very simple and straight forward.

Circuit is divided into two sections. IR TX and IR RX are to be soldered on small general purpose Grid PCB. From this module, take out 3 wires of sufficiently long length (say 1 ft). Then, as shown above, connect them to VCC, preset and to ground on main board. By adjusting preset, you can adjust sensitivity of the sensor. VCC should be connected to 5V supply.

Making the sensor module : You can follow these steps to make a sensor module ….  First cut the 1 inch piece of grid PCB such that you get 4 columns of holes .  Now Solder IR Transmitter and Receivers as shown. While bending their leads, make sure that cathode of each one comes to RHS after mounting on PCB.  Solder 470E current limiting resistor as shown.  Solder, 47nF capacitor to other end of resistor and anode of RX. Refer circuit diagram.  Now take 3 pin RMC connector and twist its wires as shown. You can also use wires of your choice, may be FRC.  Solder these wires to GND, SIGNAL and VCC points on the PCB. Refer circuit diagram. Finished !!! Testing sensor module : If you have a breadboard(BB) you can quickly test this module and see how it works. -First, connect Module on BB and connect 50K preset between vOut and GND. -Connect DMM to movable terminal of preset. -Rotate preset knob fully so that, resistance between variable terminal and ground is maximum. -Give 5V supply to sensor module. Test setup :

Here are some test results of my module :

Glow of IR LED. Since sensors in out digital cameras are sensitive to IR, we can easily see IR led glowing !! vOut when K750i’s camera flash was turned on vOut in ambient lighting. Two fluorescent lights are there in room. vOut when a piece of white paper is held near to the module. Here are some of the snaps of my sensor modules : Four IR transmitters are used to flood the surface. Sensor diode is at the centre. I had made this when I had to detect black wall. Even black colour reflects detectable IR, if irradiated sufficiently. Sensor module covered with black tape to lessen effect of ambient IR radiation. Also metal strip is glued for easier mounting on robot-car’s chassis. This is how I use sensor module with my mega16 development board. Blue preset is connected to sensor in exactly same way as shown in circuit diagram. vOut is connected to ADC input of AVR. Stepper motor A stepper motor (or step motor) is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps The motor's position can be controlled precisely, without any feedback mechanism. Stepper motors are similar to switched reluctance motors which are very large stepping motors with a reduced pole count, and generally are closedloop commutated WORKING OF THE STEPPER MOTOR Stepper motors operate differently from normal DC motors, which rotate when voltage is applied to their terminals. Stepper motors, on the other hand, effectively have multiple "toothed" electromagnets arranged around a central gear-shaped piece of iron. The electromagnets are energized by an external control circuit, such as a micro controller. To make the motor shaft turn, first one electromagnet is given power, which makes the gear's teeth magnetically attracted to the electromagnet's teeth. When the gear's teeth are thus aligned to the first

electromagnet, they are slightly offset from the next electromagnet. So when the next electromagnet is turned on and the first is turned off, the gear rotates slightly to align with the next one, and from there the process is repeated. Each of those slight rotations is called a "step," with an integer number of steps making a full rotation. In that way, the motor can be turned by a precise angle. 7 SEGMENT A seven-segment display (abbreviation: "7-seg(ment) display"), less commonly known as a seven-segment indicator, is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot-matrix displays. Seven-segment displays are widely used in digital clocks, electronic meters, and other electronic devices for displaying numerical information. The seven segments are arranged as a rectangle of two vertical segments on each side with one horizontal segment on the top, middle, and bottom. Additionally, the seventh segment bisects the rectangle horizontally. There are also fourteensegment displays and sixteen-segment displays (for full alphanumeric); however, these have mostly been replaced by dot-matrix displays. The segments of a 7-segment display are referred to by the letters A to G, where the optional DP decimal point (an "eighth segment") is used for the display of noninteger numbers. MICROCONTROLLER A microcontroller (also microcontroller unit, MCU or µC) is a small computer on a single integrated circuit consisting of a relatively simple CPU combined with support functions such as a crystal oscillator, timers, watchdog, serial and analog I/O etc. Program memory in the form of NOR flash or OTP ROM is also often included on chip, as well as a, typically small, read/write memory. Microcontrollers are designed for small or dedicated applications. Thus, in contrast to the microprocessors used in personal computers and other high-performance or general purpose applications, simplicity is emphasized. Some microcontrollers may operate at clock frequencies as low as 32kHz, as this is adequate for many typical applications, enabling low power consumption (mill watts or microwatts). They will generally have the ability to retain functionality while waiting for an event such as a button press or other interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be just Nan watts, making many of them well suited for long lasting battery applications. Other microcontrollers may

serve performance-critical roles, where they may need to act more like a Digital signal processor (DSP), using higher clock speeds and not needing such very low powered operation. Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, remote controls, office machines, appliances, power tools, and toys. By reducing the size and cost compared to a design that uses a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to digitally control even more devices and processes. Mixed signal microcontrollers are common, integrating analog components needed to control non-digital electronic systems. IR SENSOR •

Proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. A proximity sensor often emits an electromagnetic or electrostatic field, or a beam of electromagnetic radiation (infrared, for instance), and looks for changes in the field or return signal. The object being sensed is often referred to as the proximity sensor's target. Different proximity sensor targets demand different sensors. For example, a capacitive or photoelectric sensor might be suitable for a plastic target; an inductive proximity sensor requires a metal target.

• The maximum distance that this sensor can detect is defined "nominal range". Some sensors have adjustments of the nominal range or means to report a graduated detection distance. • Proximity sensors can have a high reliability and long functional life because of the absence of mechanical parts and lack of physical contact between sensor and the sensed object.

PHOTO TRANSISTOR

• A phototransistor is a type of photo detector capable of converting light into either current or voltage, depending upon the mode of operation. • Phototransistors are similar to regular semiconductor diodes except that they may be either exposed (to detect vacuum UV or X-rays) or packaged with a window or optical fiber connection to allow light to reach the sensitive part of the device.

PRINCIPLE OF OPERATION • A phototransistor is a PN junction or PIN structure. When a photon of sufficient energy strikes the diode, it excites an electron, thereby creating a mobile electron and a positively charged electron hole. If the absorption occurs in the junction's depletion region, or one diffusion length away from it, these carriers are swept from the junction by the built-in field of the depletion region. Thus holes move toward the anode, and electrons toward the cathode, and a photocurrent is produced.

Results and Conclusions We have paid parking systems all around with workers hired by the builders to manage the vehicular traffic but still there are various shortcomings as: (i) Workers cannot keep track of the no. of vehicles already present in the parking. (ii) They cannot maintain the record of the vacant slot in the parking area. (iii) As person doesn’t know about the vacant slot, therefore it creates a mess within the parking area leading to traffic jam. Thus, automatic car parking system results in the suitable control of the vehicular traffic and enables us to manage the traffic efficiently. III. Conclusion IV. Data Sheets (If Any)

Conclusions Automatic car parking is the solution to the parking problems which are increasing day by day because of the increase in the vehicular traffic. Every member of a family owns a car. Thus, the no. of cars in a particular section of the society are enormous. In any public place, there are thousands of vehicles visiting every hour. To manage such high proportion of vehicles is a tedious task. Thus for the effective control of the traffic, automatic car parking system is the best way out.

References 1. www.datasheetarchive.com 2. www.google.com 3. www.wikipedia.com 4. www.answers.com