Velocity Detector

ABSRACT

The fundamental composition of circuit comprises of two laser transmitters, LDR sensor pairs which are fixed at a distance of 100 meters from each other on highways, with the LDR and transmitter of each pair facing each other the detector displays time taken by the vehicle to cross the distance of 100m from one LDR pair to another with a resolution 0.01sec . The time taken can be used to calculate velocity by proper Formulae

vehicle

Velocity = displacement /time =0.01/{(reading*0.01)/3600} The maximum permissible speed of two highways is generally 60Kmph.However the circuit can be used as a detector for any speed limit without any change in the basic design but only changing the distance between sensor transmitting pair.

TABLE OF CONTENTS Chapter No: 1 1 1.1 2 2 3 2.1 4 2.2 3 7 3.1 8 3.2 4 11 4.1 12

Title

Page No: INTRODUCTION INTRODUCTION SYSTEM DESCRIPTION BLOCK DIAGRAM BLOCK DIAGRAM DESCRIPTION

5

CIRCUIT DESIGN CIRCUIT DIAGRAM CIRCUIT DIAGRAM DESCRIPTION PCB FABRICATION ITEMS REQUIRED

9

4.2 13 4.3 15

PROCESS

5 5.1 17

HARDWARE DESCRIPTION HARDWARES USED

6 24 6.1 25 6.2 25

MERITS AND DEMERITS

PCB LAYOUT 16

MERITS DEMERITS

8 26 9 28 10

RESULT CONCLUSION BIBLIOGRAPHY

LIST OF FIGURES Fig No:

Title

Page No

1

BLOCK DIAGRAM

2

CIRCUIT DIAGRAM

3

PCB LAYOUT

4

INTERNAL BLOCK DIAGRAM OF

5

FUNCTIONAL DIAGRAM CD4026

6

PIN DIAGRAM CD4

7

LOGIC DIAGRAM OF

4 8 15

21 22

CD4026

NE 555

18 20

23

8

TIMING DIAGRAM

CHAPTER1 INTRODUCTION

1.0 INTRODUCTION

Today large number of accidents occur due to the over speed of the drivers. Even if the legislative section is strong with laws of speed control, the implementation side is still lagging. Though this we try to equip the implementing section with some advanced and improved methods.

The system is very flexible and very easy to interpret the digital display of the device aids in calculating velocity and time taken by the vehicle to cross the transmitter section pairs. The buzzer sounds if the vehicle exceeds the permissible speed

CHAPTER 2 SYSTEM DESCRIPTION

2.1 BLOCK DIAGRAM

Fig 1: Block Diagram

2.2 BLOCK DIAGRAM DESCRIPTION

POWER SUPPLY: It consists of a 230v AC primary to 0-15v, 500mA Secondary transformer, Bridge Rectifier circuit and 7812 regulator IC. The 12v supply is given to Timers, counters &displays.

TIMER CIRCUITS:

It consists of five NE 555 timer ICs function as monostables, with IC1 serving as count start mono,IC2 as count stop mono and IC3 as speed limit detector,IC4 function as bistable reset.IC5 functions as an astable multivibrator. The 12v supply is provided for these 555 ICs.

COUNTERS:

It consists of four CD4026 counter ICs. IC CD4026 is a 5stage Johnson decade counted output decoder that converts the Johnson code into a 7-segmented decoded output for driving DISI display. The counter advances by one count at the positive clock signal transition. The carry out signal from CD4026 provides one clock after every ten clock inputs to clock the succeeding decade counter in a multi decade counting chain. This is achieved by connecting pin5 of each CD4026 to pin 1 of the next CD4026. DISPLAYS:

It consists of four LTS543 common-cathodes, 7-segment display. An output decoder converts the Johnson code into a 7-segment decoded output for driving DIS1 display. The seven decoded outputs ‘a’ through ‘g’ of CD4026 illuminate the proper segment of the 7-segment displays (DIS1 through DIS4)used for representing the decimal digits ‘0’through ‘9’.Reasistors R 16 through R 19 limit the current across DIS1 through DIS4 respectively. The time taken by the vehicles to cross both the laser beams is displayed on the 7-segment display.

CHAPTER 3 CIRCUIT DESCRIPTION

3.0 CIRCUIT DIAGRAM

Fig 2: Circuit Diagram

3.1 CIRCUIT DIAGRAM EXPLANATION The circuit consists of five NE 555 IC’s. First three 555 ICs function as monostables, IC1 count-start monostable is adjusted using preset VR1or VR2 and capacitor C1.Using preset VR1,while for 60kmph limit the time period is set for 6sec.usingVR2.Slide switches is used to select the time period as per the speed limit. Normally, light from the laser keeps falling on the LDR sensor continuously and thus the LDR offers a low resistance and pin 2 of IC1 is high. Whenever light falling on the LDR is interrupted by any vehicle, the LDR resistance goes high and hence pin2 of IC1 goes low to trigger the monostable. As a result of this, pin 3 goes high for the preset period and LED1 glows to indicate it. For IC2,the monostable is triggered in the same way as IC1 when the vehicle intersect the laser beam incident on LDR2 to generate a small pulse for stopping the count and for use in the speed detection. LED2 glows for the duration for which pin 3 of IC2 is high. The outputs of IC1 and IC2 are fed to input pins 2 and 1 of NAND gate N1 respectively. When the outputs of IC1 and IC2 go high simultaneously, pin 3 of gate N1 goes low to trigger monostable timer IC3. The output of IC3 is used for driving piezobuzzer PZ1 which alters the operator of speed limit violation.

The output of IC1 triggers bistable through N2 at the leading edge of the countstart pulse. When pin 2 of IC 4 goes low, the high output at the pin 3 enables IC5.Since the count-stop pulse output of IC2 is connected to pin 6 of IC 4 via diode D1,it resets IC5. IC CD4026 is a 5-stage Johnson decade counter and output decoder that converts the Johnson code into a 7-segment decoded output for driving DIS1 display. The counter advances by one count at the positive clock signal transition. The carry-out signal from CD4026 provides one clock after every ten clock inputs to clock the succeeding decade counter in a multi decade counting chain. This is achieved by connecting pin 5 of each CD4026 to pin 1 of the next CD4026. It consists of four LTS543 commoncathodes, 7-segment decoded output for driving DIS1 display. The seven decoded output ‘a’ through ‘g’ of CD4206s illuminate the proper segment of the 7-segment display.DIS1 through DIS4)used for representing the decimal digits ‘0’through ‘9’.Reasistors R 16 through R 19 limit the current across DIS1 through DIS4 respectively.

CHAPTER 4 PCB FABRICATION

4.0 PCB FABRICATION

4.1 ITEMS REQUIRED:

1. Single sided copper clad. 2. Hand drill and bits small type of the work bench with a 0.8 mm bits. 3. Quick setting etches resistant paint, nail polish, or poster color is equally good. Permanent markers are also used to paint the circuit on the board. 4. Painting brush: water color brush for smooth painting and to draw lines. 5. Etching solution: Ferric chloride available in 500 gram pack, very pure quality is not required. 6. Dish: take an enamel dish, flat at bottom and wide enough to accept the work piece.

4.2 PROCESS:

Drafting : Prepare the PCB layout of the circuit diagram on a graph paper. For this draw the component layout. After this printed circuit portion is made on the graph sheet. Compare the art work with actual circuit, check whether actual dimension for each component are provided and the measure the board size. Copper clad is cut into required size and is cleaned.

Printing: Art work is transferred into the copper clad using a carbon paper. Print the art with paint or permanent marker. Avoid too narrow and too wide lines. While drawing printed circuit follow the rule signal < supply> ground.

Etching: Wash the dish then take water enough to immerse the board and add ferric chloride carefully. Ferric chloride is limiting to skin and will stain the cloths. After drawing the clad is immersed into the ferric chloride solution with copper side up. Stir the solution by giving zigzag motion to the dish and the solution in it after dipping the clad. Ferric chloride will etch the exposed area and will not affect the wax layer. After etching the board is taken from the dish and washed in running water. Then rub with punnice to remove the coating of etch resistant till we obtain shinning copper.

Drilling: After etching and cleaning the PCB, pads are drilled with high speed drilling machines for making it easier, punch the pads before drilling. Apply a coat of varnish to printed side, will maintain the shinning and act as an agent to corrosion

PCB LAYOUT

Fig 3 PCB Layout

CHAPTER 5 HARDWARE DESCRIPTION 5.0 HARDWARE DESCRIPTION 5.1 HARDWARES USED 5.1.1 NE555

Single Timer

FEATURES High current drive capability (200mA) Adjustable duty cycle Temperature stability of 0.005%/0c Timing from µsec to hours APPLICATION Precision timing Pulse generator Time delay generator Sequential timing DESCRIPTION The LM555/NE555/SA555 is a highly stable controller capable of producing accurate timing pulse. With monostable operation ,the time delay is controlled by one external resistor and one capacitor. with astable operation , the frequency and duty cycle are accurately controlled with two external resistors and one capacitor.

INTERNAL BLOCK DIAGRAM

Fig 4 : Internal Block Diagram Of

CD 4026

NE 555

FEATURES Counter and seven segment decoding in one package Easily interfaced with seven segment display types Ideal for low power displays Schmitt triggered, clock

input

APPLICATIONS Decade counting seven segment decimal display Frequency division seven segment

display

Clocks ,watches, timers Counter / display driver for meter applications

FUNCTIONAL DIAGRAM

Fig 5 : Functional Diagram CD4026

PIN DIAGRAM

Fig 6: Pin Diagram CD4026

LOGIC DIAGRAM Fig 7: Logic Diagram Of

TIMING DIAGRAM

CD4026

Fig 8:Timing Diagram

CHAPTER 6 MERITS AND DEMERITS

6.0 MERITS AND DEMERITS 6.1MERIT Convenient Reliability Cost effective 6.2 DEMERIT

The major demerit of the circuit is that it can check the speed of only one vehicle at a time.

CHAPTER 7 RESULT

7.0 RESULT

The seminar is found to be cent percent sincere towards the aim for which it was designed for. The time taken by the vehicle to pass both the laser beams and also the speed of the vehicle has been calculated from the reading of the seven segment display. If the vehicle exceeds the permissible speed the buzzer sounds the alarm.

CHAPTER 8 CONCLUSION

8.0 CONCLUSION

The seminar was completed with success and the most striking about this seminar is that the circuit can be used for any speed limit without any change in speed design. The violation of traffic rules can be reduced to a certain extent with the help of the velocity detector. Through this attempt we enrich our self with the courage ad confidence to under take these kinds of work in future also. It also caused us to enrich our knowledge regarding the design, construction, fabrication and other aspects of any device

CHAPTER 9 BIBLIOGRAPHY

9.0 BIBLIOGRAPHY 9.1 TEXT BOOK Ramkanth A Gayakwad

-

“op-amps and linear integrated

circuits”,prentice Hall of India,2007. 9.2 WEBPAGE www.projectguidance.com www.datashetcatalog.com www.fairchildsemi.com