Speed checker on highway using 8051
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Speed checker on highway using 8051

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Speed checker on highway using 8051 micro controller and IR sensors. Here IR sensor sense the speed of the vehicle and and controller display the speed on Liquid Crystal Display,

Speed checker on highway using 8051 micro controller and IR sensors. Here IR sensor sense the speed of the vehicle and and controller display the speed on Liquid Crystal Display,

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Speed checker on highway using 8051 Speed checker on highway using 8051 Document Transcript

  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 1 CHAPTER 1 INTRODUCTION 1.1 INTRODUCTION TO PROJECT A system designed to record and report on discrete activities within a process is called as Tracking System. In the same procedure we have developed a methodology of vehicle speed & direction system for robotics to control and achieve accurate direction speed for a class of non-linear systems in the presence of disturbances and parameter variations by using wireless communication technique. While driving on highways, motorists should not exceed the maximum speed limit permitted for their vehicle. However, accidents keep occurring due to speed violations since the drivers tend to ignore their speedometers. This speed checker will come handy for the highway traffic police as it will not only provide a digital display in accordance with a vehicle’s speed but sound an alarm if the vehicle exceeds the permissible speed for the highway. The system basically comprises two IR LED’s Transistor & receiver sensor pairs, which are installed on the highway 100cm apart, with the transmitter and the receiver of each pair on the opposite sides of the road. The system displays the time taken by the vehicle in crossing this distance from one pair to the other from which the speed of the vehicle can be calculated as follows: Here, Distance is the total distance between the pair of sensors. Time is the interval between crossing the first sensor and second sensor. Microcontroller 8051 is the heart of the system, which control all the function of the circuit. It measures the speed and control the circuit through a programming flashed inside 8051. IR sensor are used as a pair of eye that keep watching the speed of each vehicle crossing the sensors. A seven segment display is used to display the total speed of the vehicle (After calculation is done inside controller.).
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 2 1.2 BLOCK DIAGRAM fig 1: Block Diagram
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 3 CHAPTER 2 WORKING OF THE SYSTEM 2.1 WORKING In this project we use IR sensors to detect the presence of a vehicle. According to this project, 2 IR sensors are placed apart with a fixed known distance. Whenever IR rays are interrupted by a vehicle during first sensor the count up timer is started. When the other IR sensor senses the presence of vehicle, the count up timer is stopped. As the distance and time the IR receiver receives the IR signals is noted by microcontroller and from that we need to calculate speed. Here speed is calculated from the well-known formula of speed which is distance/time. The Seven segment display is used to display the speed of the vehicle. The microcontroller is used to monitor the all control operations needed for the project. 2.1.1 Power Supply The 8051 microcontroller works on +5V DC. Now here we have 220V AC as the input. So first of all, we need to step down the voltage using transformer. Here the transformer will step down the 220V AC to 9V AC at 50Hz. To convert AC to DC, a bridge rectifier is placed using 1N4007, a p-n diode. Two capacitor of 470µF & .01µF is used as a filter. Now, this DC output is fed to a 7805 voltage regulator which will convert the DC input into +5V DC. Fig 2.1: Power supply
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 4 2.1.2 8051 8051 block consist of the P89V51RD2 microcontroller. It will run on the frequency of about 11.0592 MHz. 8051 is the brain of the system. All the components will drive by the instructions provided by the microcontroller through a programming code burn inside the 8051. Pin diagram of Microcontroller 8051 is shown below. Fig 2.2: 8051 Pin diagram 2.2 CIRCUIT DIAGRAM The main circuit diagram of the project is shown below.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 5 Fig 2.3: Main circuit (a) 2.3 PCB LAYOUT Fig 2.6: PCB Layout
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 6 2.3 PROGRAM #include<reg51.h> sfr LCD=0x80; sbit RS=P2^6; sbit EN=P2^7; unsigned int a=0, i=0, v; void tm(); void delay(unsigned char time) { unsigned int a,b; for(a=0;a<time;a++) for(b=0;b<1275;b++); } void lcdcmd(unsigned char value) { LCD=value; RS=0; EN=1; delay(10); EN=0; } void lcddata(unsigned char value) { LCD=value; RS=1; EN=1; delay(10); EN=0; } void lcd_init() {
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 7 lcdcmd(0x38); delay(20); lcdcmd(0x0c); delay(20); lcdcmd(0x01); delay(20); lcdcmd(0x06); delay(20); } void ISR_ex0(void) interrupt 0 { while(1) { tm(); a++; } } void ISR_ex1(void) interrupt 2 { unsigned char m,n,temp,o; v=100/a; m=v/100; temp=v%100; n=temp/10; o=temp%10; lcdcmd(0xc6); lcddata(m+48); lcddata(n+48); lcddata(o+48); a=0; lcddata('m');
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 8 lcddata('m'); lcddata('/'); lcddata('s'); lcddata('e'); lcddata('c'); lcddata(' '); lcddata(' '); } void main() { unsigned char w[]="WELCOMESPEED=WAITING..."; IT0 = 1; // Configure interrupt 0 for falling edge on /INT0 (P3.2) EX0 = 1; // Enable EX0 Interrupt IT1 = 1; // Configure interrupt 1 for falling edge on /INT0 (P3.2) EX1 = 1; // Enable EX1 Interrupt EA = 1; // Enable Global Interrupt Flag IP=0x04; // Priority of ex1 high lcd_init(); lcdcmd(0x84); for(i=0;i<7;i++) lcddata(w[i]); lcdcmd(0xc0); for(i=7;i<13;i++) lcddata(w[i]); for(i=13;i<24;i++) lcddata(w[i]); while(1); } void tm() { int y=0;
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 9 for(y=0;y<15;y++) { TMOD=0x01; TL0=0xFD; TH0=0x4B; TR0=1; while(TF0==0); TR0=0; TF0=0; } }
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 10 CHAPTER 3 COMPONENTS USED IN THE PROJECT 3.1 COMPONENT LIST 1. INTEGRATED CIRCUIT  P89V51RD2  7805 2. SWITCH  PUSH-TO-ON Switch 3. DIODE  1N4007 PN Diode 4. CAPACITORS  1000µF 25V  22pF  100nF 50V  10µF 40V 5. RESISTORS  220Ω  470Ω  10 KΩ  SIP-Resistor 10KΩ 6. CRYSTAL  11.0592MHz 7. TRANSFORMER 8. LCD 9. IR LED 10. LED 11. PRESET
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 11 3.2 COMPONENT DESCRIPTIONS 3.2.1 INTEGRATED CIRCUIT  P89V51RD2 The P89V51RD2 is an 8051 microcontroller with 64 kB Flash and 1024 bytes of data RAM. Fig 3.1: P89V51RD2 Pin Diagram P0.0 to P0.7 -Port 0: Port 0 is an 8-bit open drain bidirectional I/O port. Port 0 pins that have ‘1’s written to them float, and in this state can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external code and data memory. In this application, it uses strong internal pull-ups when transitioning to ‘1’s. Port 0 also receives the code bytes during the external host mode programming, and outputs the code bytes during the external host mode verification. External pull-ups are required during program verification or as a general purpose I/O port. P1.0 to P1.7 -Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 pins are pulled high by the internal pull-ups when ‘1’s are written to them and can be used as inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 12 source current (IIL) because of the internal pull-ups. P1.5, P1.6, P1.7 have high current drive of 16 mA. Port 1 also receives the low-order address bytes during the external host mode programming and verification. P2.0 to P2.7 -Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2 pins are pulled HIGH by the internal pull-ups when ‘1’s are written to them and can be used as inputs in this state. As inputs, Port 2 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. Port 2 sends the high-order address byte during fetches from external program memory and during accesses to external Data Memory that use 16-bitaddress (MOVX@DPTR). In this application, it uses strong internal pull-ups when transitioning to ‘1’s. Port 2 also receives some control signals and a partial of high-order address bits during the external host mode programming and verification. P3.0 to P3.7 -Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins are pulled HIGH by the internal pull-ups when ‘1’s are written to them and can be used as inputs in this state. As inputs, Port 3 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. Port 3 also receives some control signals and a partial of high-order address bits during the external host mode programming and verification. PSEN - Program Store Enable: PSEN is the read strobe for external program memory. When the device is executing from internal program memory, PSEN is inactive (HIGH).When the device is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory. A forced HIGH-to-LOW input transition on the PSEN pin while the RST input is continually held HIGH for more than 10 machine cycles will cause the device to enter external host mode programming. RST -Reset: While the oscillator is running, a HIGH logic state on this pin for two machine cycles will reset the device. If the PSEN pin is driven by a HIGH-to-LOW input transition while the RST input pin is held HIGH, the device will enter the external host mode; otherwise the device will enter the normal operation mode. EA -External Access Enable: EA must be connected to VSS in order to enable the device to fetch code from the external program memory. EA must be strapped to VDD for internal program execution. The EA pin can tolerate a high voltage of 12 V.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 13 ALE- Address Latch Enable: ALE is the output signal for latching the low byte of the address during an access to external memory.  7805 The 78xx (also sometimes known as LM78xx) series of devices is a family of self- contained fixed linear voltage regulator integrated circuits. The 78xx family is a very popular choice for many electronic circuits which require a regulated power supply, due to their ease of use and relative cheapness. When specifying individual ICs within this family, the xx is replaced with a two-digit number, which indicates the output voltage the particular device is designed to provide (for example, the 7805 has a 5 volt output, while the 7812 produces 12 volts). Figure 3.2: IC 7805 The 78xx lines are positive voltage regulators, meaning that they are designed to produce a voltage that is positive relative to a common ground. There is a related line of 79xx devices which are complementary negative vo1623ltage regulators. 78xx and 79xx Ics can be used in combination to provide both positive and negative supply voltages in the same circuit, if necessary. 78xx Ics have three terminals and are most commonly found in the TO220 form factor, although smaller surface-mount and larger TO3 packages are also available from some manufacturers. These devices typically support an input voltage which can be anywhere from a couple of volts over the intended output voltage, up to a maximum of 35 or 40 volts, and can typically provide up to around 1 or 1.5 amps of current (though smaller or larger packages may have a lower or higher current rating).
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 14 3.2.2 SWITCH  PUSH-TO-ON Push-to-on switch holds the circuit conducting while the switch is pressed. But when the switch is released, the circuit stops conducting. On the other hand, two way switches doesn’t need to pressed continue. It do not require the continue effort to on the circuit. It has two states. When the switch is slides to left, switch gives 1 and if it slides to right, the output is 0. Figure 3.4: PUSH-TO-ON Switch 3.2.3 DIODE  1N4007 PN DIODE The diode used here is a p-n junction diode i.e. 1N4007. Its reverse breakdown voltage is 1000V. This diode is used as the rectifier. Figure 3.5: 1N4007 3.2.4 CAPACITORS In the project, two types of capacitors are used. 1. Electrolytic (47µF 50V, 10µF 40V, 470µF 25V)
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 15 2. Ceramic Disc (33pF) Electrolytic capacitors are polarized capacitors are made of oxide film on aluminum foils. These are cheaper and easily available. The range of values typically varies from 1uF to 47000uF and large tolerance of 20%. The voltage ratings range up to 500V. They have high capacitance to volume ratio and used for smoothing in power supply circuits or coupling capacitors in audio amplifiers. These are available in both leaded and surface mount packages. The capacitance value and voltage ratings are either printed in µF. Figure 3.6: Electrolytic Capacitor The non – polarized type ceramic capacitors which are also known as ‘Disc capacitors’ are widely used these days. These are available in millions of varieties of cost and performance. The features of ceramic capacitor depend upon: Type of ceramic dielectric used in the capacitor which varies in the temperature coefficient and Dielectric losses. The exact formulas of the different ceramics used in ceramic capacitors vary from one manufacturer to another. The common compounds such as titanium dioxide, strontium titanate, and barium titanateare the three main types available although other types such as leaded disc ceramic capacitors for through hole mounting which are resin coated, multilayer surface mount chip ceramic capacitors and microwave bare leadless disc ceramic capacitors that are designed to sit in a slot in the PCB and are soldered in place
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 16 Figure 3.7: Ceramic Capacitor 3.2.5 RESISTORS Resistor is a passive component used to control current in a circuit. Its resistance is given by the ratio of voltage applied across its terminals to the current passing through it. Thus a particular value of resistor, for fixed voltage, limits the current through it. They are omnipresent in electronic circuits. Figure 3.8: Resistor The different value of resistances are used to limit the currents or get the desired voltage drop according to the current-voltage rating of the device to be connected in the circuit. For example, if an LED of rating 2.3V and 6mA is to be connected with a supply of 5V, a voltage drop of 2.7V (5V-2.3V) and limiting current of 6mA is required. This can be achieved by providing a resistor of 450 connected in series with the LED.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 17 3.2.6 CRYSTAL A quartz crystal resonator plays a vital role in electronics oscillator circuitry. Sometimes mispronounced as crystal oscillator, it is rather a very important part of the feedback network of the oscillator circuitry. Electronics oscillators are used in frequency control application finding their usage in almost every industry ranging from small chips to aerospace. Figure 3.9: Crystal A quartz crystal is the heart of such type of resonators. Their characteristics like high quality factor (Q), stability, small size and low cost make them superior over other resonators like LC circuit, turning forks, ceramic resonator etc. The basic phenomenon behind working of a quartz crystal oscillator is the inverse piezo electric effect i.e., when electric field is applied across certain materials they start producing mechanical deformation. These mechanical deformation/movements are dependent on the elementary structure of the quartz crystal. Quartz is one of the naturally occurring materials which show the phenomena of piezo electricity; however for the purpose of resonator it is artificially developed since processing the naturally occurring quartz is difficult and costly process. 3.2.7 TRANSFORMER The transformer is a static electro-magnetic device that transforms one alternating voltage (current) into another voltage (current). However, power remains the same during the transformation. Transformers play a major role in the transmission and distribution of ac power. Principle
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 18 Transformer works on the principle of mutual induction. A transformer consists of laminated magnetic core forming the magnetic frame. Primary and secondary coils are wound upon the two cores of the magnetic frame, linked by the common magnetic flux. When an alternating voltage is applied across the primary coil, current flows in the primary coil producing magnetic flux in the transformer core, this flux induces voltage in secondary coil. Transformers are classified as: - (a) Based on position of the windings with respect to core i.e. 1) Core type transformer 2) Shell type transformer (b) Transformation ratio: 1) Step up transformer 2) Step down transformer a) Core & shell types: Figure 3.10: Step-Up Transformer. Figure 3.11: Step-Down Transformer Transformer is simplest electrical machine, which consists of windings on the laminated magnetic core. There are two possibilities of putting up the windings on the core. 1) Winding encircle the core in the case of core type transformer
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 19 2) Cores encircle the windings on shell type transformer. b) Step up and Step down: In these voltages transformation takes place according to whether the primary is high voltage coil or a low voltage coil. 1) Lower to higher-> Step up 2) Higher to lower-> Step down 3.2.8 LCD LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of applications. A 16x2 LCD display is very basic module and is very commonly used in various devices and circuits. These modules are preferred over seven segments and other multi segment LEDs. The reasons being: LCDs are economical; easily programmable; have no limitation of displaying special & even custom characters (unlike in seven segments), animations and so on. A 16x2 LCD means it can display 16 characters per line and there are 2 such lines. In this LCD each character is displayed in 5x7 pixel matrix. This LCD has two registers, namely, Command and Data. The command register stores the command instructions given to the LCD. A command is an instruction given to LCD to do a predefined task like initializing it, clearing its screen, setting the cursor position, controlling display etc. The data register stores the data to be displayed on the LCD. The data is the ASCII value of the character to be displayed on the LCD. Click to learn more about internal structure of a LCD. Figure 3.12: LCD
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 20 Figure 3.13: LCD Description 3.2.9 IR LED Here the IR transmitter is nothing but the IR LED. It just looks like a normal LED but transmits the IR signals. Since the IR rays are out of the visible range we cannot observe the rays from the transmitter. These are infrared LEDs; the light output is not visible by our eyes. They can be used as replacement LEDs for remote controls, night vision for camcorders, invisible beam sensors, etc. Fig 3.14: IR LED
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 21 3.2.10 LED A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Appearing as practical electronic components in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light Figure3.15: LED is determined by the energy gap of the semiconductor. LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. As its name implies it is a diode, which emits light when forward biased. Charge carrier recombination takes place when electrons from the N-side cross the junction and recombine with the holes on the P side. Electrons are in the higher conduction band on the N side whereas holes are in the lower valence band on the P side. During recombination, some of the energy is given up in the form of heat and light. In the case of semiconductor materials like Gallium arsenide
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 22 (GaAs), Gallium phosphide (GaP) and Gallium arsenide phosphide (GaAsP) a greater percentage of energy is released during recombination and is given out in the form of light. LED emits no light when junction is reversed biased. 3.2.11 PRESET A preset is a three legged electronic component which can be made to offer varying resistance in a circuit. The resistance is varied by adjusting the rotary control over it. The adjustment can be done by using a small screw driver or a similar tool. The resistance does not vary linearly but rather varies in exponential or logarithmic manner. Such variable resistors are commonly used for adjusting sensitivity along with a sensor. The variable resistance is obtained across the single terminal at front and one of the two other terminals. The two legs at back offer fixed resistance which is divided by the front leg. So whenever only the back terminals are used, a preset acts as a fixed resistor. Presets are specified by their fixed value resistance. Fig 3.16: Preset 3.3 COST ANALYSIS Name Cost (Unit Price) 1. INTEGRATED CIRCUIT  P89V51RD2 300/-  7805 5/- 2. SWITCH  PUSH-TO-ON Switch 3/- 3. DIODE  1N4007 PN Diode 3/-
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 23 4. CAPACITORS  1000µF 25V 5/  33pF 1/  47µF 50V 2/-  10µF 40V 2/- 5. RESISTORS  8.2 KΩ 0.50/-  SIP-Resistor 10KΩ 10/- 6. CRYSTAL  11.0592MHz 15/- 7. TRANSFORMER 60/- 8. LCD 280/- 9. IR LED 50/- 10. LED 2/- 11. PRESET 10/-
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 24 CHAPTER 4 TESTING & PROBLEMS 4.1 TESTING PROCEDURE First of all we do the continuity test to check whether there is any short circuit or not in our PCB. We don’t apply the power supply to our circuit before testing, without power supply testing is called COLD Testing. We test all the components used in our project. A brief description is given below about testing procedure. In electronics, a continuity test is the checking of an electric circuit to see if current flows (that it is in fact a complete circuit). A continuity test is performed by placing a small voltage (wired in series with an LED or noise-producing component such as a piezoelectric speaker) across the chosen path. If electron flow is inhibited by broken conductors, damaged components, or excessive resistance, the circuit is "open". Devices that can be used to perform continuity tests include multi meters which measure current and specialized continuity testers which are cheaper, more basic devices, generally with a simple light bulb that lights up when current flows. Making sure something is not connected. Sometimes a solder joint will short two connections. Or maybe your PCB has mistaken on it and some traces were shorted by accident. Figure 4.1: Continuity Testing. This meter is very simple. When the probes are not touching, the display shows "1". When you touch the tips together, the display changes to a three digit mode (it's displaying resistance, which we will cover later) It also emits a beep. Set your meter to the continuity/diode "bleep" test. Connect the red meter lead to the base of the transistor.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 25 Connect the black meter lead to the emitter. A good NPN transistor will read a junction drop voltage of between 0.45v and 0.9v. A good PNP transistor will read "OL". Leave the red meter lead on the base and move the black lead to the collector. The reading should be the same as the previous test. Reverse the meter leads in your hands and repeat the test. Now connect the black meter lead to the base of the transistor. Connect the red meter lead to the emitter. A good PNP transistor will read a junction drop voltage of between 0.45v and 0.9v. A good NPN transistor will read "OL". Leave the black meter lead on the base and move the red lead to the collector. The reading should be the same as the previous test. Finally place one meter lead on the collector, the other on the emitter. The meter should read "OL". Reverse your meter leads. The meter should read "OL". This is the same for both NPN and PNP transistors. With the transistors on a pcb in circuit, you may not get an accurate reading, as other things in the circuit may affect it, so if you think a transistor is suspect from the readings you have got, remove it from the pcb and test it out of circuit, repeating the above procedure. 4.2 TESTING FOR POWER SUPPLY Every component was checked for short circuit through multimeter. Power supply is given & the output of the various components is tested. Output of the transformer -9 volts A.C Output of the rectifier – 9 volt D.C Output of the regulator – 5 Volt D.C Output of the regulator with load - 4.80 Volt D.C 4.3 PROBLEM FACED IN THE PROJECT While building the project, there were some problems faced: 1. Testing of electronic components or circuit is very interesting work. In my project we don’t faced any serious problem. By testing we got a shorted path in our circuit on PCB and there are 3-4 tracks which are broken during etching process. We joint these tracks by tinning. 2. The first problem were soldering, it were not easy to solder the components on the PCB, so the method suggested by the guide were, to apply the solder mask.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 26 CHAPTER 5 ADVANTAGES & APPLICATIONS 5.1 ADVANTAGES  The circuit is also running on +5V which is easier to generate.  They reduce the risk of accidents.  It is easy to implement.  It reduce the effort of many men. 5.2 DISADVANTAGES  Sometimes the circuit got failure and causes various problems. 5.3 APPLICATION  Bridge construction.  Highways.  Two lane road construction.  Emergency response.  Event Traffic control.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 27 CONCLUSION The project “SPEED CHECKER FOR HIGHWAYS” has been successfully designed and tested. It has been developed by integrating features of all the hardware components used. Presence of every module has been reasoned out and placed carefully thus contributing to the best working of the unit. Secondly, using highly advanced IC’s and with the help of growing technology the project has been successfully implemented. Finally we conclude that “SPEED CHECKER FOR HIGHWAYS” is an emerging field and there is a huge scope for research and development. It can be further advanced by using a CCTV camera in the circuit. Whenever any vehicle crosses speed limit, camera captures the image of number plate and through transport database finds the address of the owner and sends fine.
  • MAJOR PROJECT SPEED CHECKER ON HIGHWAY DEPARTMENT OF ELECTRONICS & COMMUNICATION 28 BIBLIOGRAPHY 1. http://www.engineersgarage.com/ 2. http://engineeringactivity.com/ 3. http://www.pantechsolutions.net/ 4. http://www.8051projects.net/ 5. http://www.dnatechindia.com/