visvesvaraya technological univeristy

VISVESVARAYA TECHNOLOGICAL UNIVERISTY

JNANASANGAMA, BELAGAVI-590018

A Project Report

on

“AUTOMATIC RAIN SENSING WIPER SYSTEM”

Submitted in partial fulfillment for the award of degree of

Bachelor of Engineering

In

MECHANICAL ENGINEERING

Submitted by

NITHIN PV 1NH12ME738

LOHITH A 1NH12ME731

GIRISH KUMAR DN 1NH13ME407

VENKATESH MN 1NH13ME431

Carried Out under the Guidance

of

Mr NAGENDRA J

Asst. Professor

DEPARTMENT OF MECHANICAL ENGG.

NEW HORIZON COLLEGE OF ENGINEERING

Kadubeesanahalli, Bellandur Post, Near Marathalli, Bengaluru, Karnataka -560103

2015-16

DEPARTMENT OF MECHANICAL ENGINEERING


(Accredited by NAAC with „A‟ Grade, Permanently afflicted to VTU)


CERTIFICATE

This is to certify that the Project entitled “AUTOMATIC RAIN SENSING WIPER

SYSTEM” is a bonafide work carried out by NITHIN PV, bearing USN: 1NH12ME738, LOHITH A

bearing USN:1NH12ME731, GIRISH KUMAR DN bearing USN:1NH13ME406, VENKATESHA

MN bearing USN:1NH13ME431 in partial fulfillment for the award of the degree of Bachelor of

Engineering in MECHANICAL ENGINEERING affiliated to Visvesvaraya Technological

University, Belagavi during the academic year 2015-2016. It is certified that all corrections/suggestions

indicated for project have been incorporated in the report deposited in the department library. The project

report has been approved as it satisfies the academic requirements with respect to project work prescribed

for the Bachelor of Engineering.

………………… ..………………….. ...…………………

NAME Dr. MS GANESH PRASAD Dr. MANJUNATH

Internal guide HOD Principal

ACKNOWLEDGEMENT

The successful completion of any project depends on help and co-ordination of many

people other than those who directly execute the work.

It is difficult to express in words our profound sense of gratitude to those who helped us but we

make a sense of gratitude to do so.

We wish to express our deep gratitude and indebtedness to our institution NEW HORIZON

COLLEGE OF ENGINEERING, which has provided us with the opportunity in fulfilling our

desire of becoming Mechanical Engineers.

We are grateful to Dr. V MANJUNATH, Principal NHCE & Dr. MS GANESH PRASAD,

HOD of Mechanical Engineering Dept. for their moral and academic guidance along with their

support through our period of study and completion of this project.

We sincerely acknowledge the full support and guidance to us, and we express our deep sense of

gratitude for our guide Mr NAGENDRA J, Assistant Professor, Dept. of Mechanical for his

timely suggestions along with constant evaluations of our progress helped us to speed up the

work and make it highly knowledge oriented. Our special thanks to him.

Our own lab staff have lent their helping hand whenever necessary. Our special thanks to all of

them.

Various peoples assisted us either directly or indirectly during execution of our project. We take

this opportunity to thank all of them who have helped us in successful completion of this project.

DEPARTMENT OF MECHANICAL ENGINEERING


(Accredited by NAAC with „A‟ Grade, Permanently afflicted to VTU)


DECLARATION

I hereby declare that the entire work embodied in this project report titled, “AUTOMATIC

RAIN SENSING WIPER SYSTEM” submitted to Visvesvaraya Technological University,

Belagavi is carried out by me at Department of Mechanical Engineering ,New Horizon College

of Engineering Bengaluru, under the guidance of Mr Nagendra J, Asst. Professor. This thesis

has not been submitted in part or full for the award of any diploma or degree of this or any other

University.

SIGNATURES

NITHIN PV

LOHITH A

GIRISH KUMAR DN

VENKATESH MN

I

ABSTRACT

The world today is moving ahead at a very fast pace. Some of the very common

examples of fast moving objects are aeroplanes, high speed cars and many more. In our

everyday life we come across many fast moving vehicles and so it is very important to

measure the speed of these vehicles.

This is an era of automation where it is broadly defined as replacement of manual effort by

mechanical power in all degrees of automation. The operation remains an essential part of the

system although with changing demands on physical input as the degree of mechanization is

increased.

Rain operated motor is consists of conduction sensor (Tough sensor) circuit, Control Unit,

wiper motor and glass frame. The sensor is used to detect the rain or water flow. There is any

rain on the class, the sensor senses the rain or flow water and giving the control signal to the

wiper motor.

CONTENTS

1. INTRODUCTION

1.1 HISTORY……………………………………………………………….1

1.2 LITERATURE SURVEY……………………………………………… 5

2 AUTOMATION

2.1 INTRODUCTION………………………………………………….12

2.2 NEED FOR AUTOMATION………………………………………12

2.3 ADVANTAGES……………………………………………………...13

2.4 DISADVANTAGES…………………………………………………14

2.5 AUTOMATION TOOLS…………………………………………….14

3. WINDSCREEN WIPER

3.1 HISTORY …………………………………………………………18

3.2 INTERMITTENT WIPERS……………………………………….. 20

3.3 POWER…………………………………………………………….21

3.4 GEOMETRY……………………………………………………….24

4. SYSTEM OVERVIEW

4.1 PURPOSE OF DEVELOPMENT……………………………………25

4.2 SYSTEM CONFIGURATION………………………………………26

5. WORKING OF CIRCUIT

5.1 PROJECT SPECIALITIES ……………………………………… 28

5.2 TECHNICAL DESCRIPTION AND WORKING…………………29

6. PART LIST

6.1 FOR AUTOMATIC WIPER SPEED MOTOR CONTROLLER……31

7. CIRCUIT

7.1 AUTOMATIC WIPER CONTROL SYSTEM………………………32

8. ELECTRONIC COMPONENT

8.1 RESISTANCE………………………………………………………33

8.2 CAPACITOR………………………………………………………..35

8.3 SPEAKER/EAR PHONE……………………………………………36

8.4 KEY SWITCH………………………………………………………37

8.5 TRANSISTOR……………………………………………………….38

8.6 TRANSFORMER…………………………………………………….39

8.7 LIGHT DEPENDENT RESISTANCE………………………………40

8.8 COIL …………………………………………………………………41

8.9 IC 555………………………………………………………………43

8.10 PRESET…………………………………………………………….44

9. ADVANTAGES

9.1 HOW DO THEY INCREASE DRIVER SAFETY ……………….46

10. APPLICATIONS…………………………………………………… 48

Cost Estimation………………………………………………………49

Conclusion........................................................................................50

LIST OF FIGURES

1. Fig.3.1 Windscreen Wiper……………………………………..18

2. Fig.3.2 Pneumatic motor drive in train……………………….19

3. Fig.3.3-3.12 Wiper geometry…………………………………..24

4. Fig. 4.1 System configuration ……………………………….26

5. Fig 5.1 Block diagram of wiper system………………………29

6. Fig.7.1 Automatic Wiper Control System Circuit…………. 32

7. Fig.8.1 Resistor…………………………………………......... 34

8. Fig.8.2 Capicitor……………………………………………….35

9. Fig.8.3 Operation of Capacitor……………………………....36

10. Fig.8.4 Key Switch…………………………………………… 37

11. Fig.8.8 IC 555………………………………………………… 42

12. Fig.8.5 Transistor.......................................................................38

13. Fig.8.6 Coil …………………………………………………….41

14. Fig.8.7 Relay with Transformer...............................................41

15. Fig.8.9 Rain Sensor…………………………………………....44

AUTOMATIC RAIN SENSING WIPER 2015-16

NHCE-MECHANICAL DEPARTMENT

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CHAPTER 1

INTRODUCTION

1.1 HISTORY

At least three inventors patented windscreen cleaning devices at around the same time

in 1903; Mary Anderson, Robert Douglass, and John Apjohn.

Anderson's 1903 window cleaner design

American inventor Mary Anderson is popularly credited with devising the first

operational windshield wiper in 1903. In Anderson's patent, she called her invention a

"window cleaning device" for electric cars and other vehicles. Operated via a lever from

inside a vehicle, her version of windshield wipers closely resembles the windshield wiper

found on many early car models. Anderson had a model of her design manufactured, then

filed a patent (US 743,801) on June 18, 1903 that was issued to her by the US Patent Office

on November 10, 1903.

Douglass's 1903 locomotive cab window cleaner

A similar device is recorded 3 months prior to Anderson's patent, with Robert A

Douglass filing a patent for a "locomotive-cab-window cleaner" on 12 March 1903.[5]

Apjohn's 1903 window cleaning apparatus design

Irish born inventor James Henry Apjohn (1845–1914) patented an "Apparatus for

Cleaning Carriage, Motor Car and other Windows" which was stated to use either brushes or

wipers and could be either motor driven or hand driven. The brushes or wipers were intended

to clean either both up and down or in just one direction on a vertical window. Apjohn's

invention had a priority date in the UK of 9 October 1903.[6]

In April 1911, a patent for windscreen wipers was registered by Sloan & Lloyd

Barnes, patent agents of Liverpool, England, for Gladstone Adams of Whitley Bay. The first

designs for the windscreen wiper are also credited to Polish concert pianist Józef Hofmann,

and Mills Munitions, Birmingham who also claimed to have been the first to patent



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windscreen wipers in England.

John R. Oishei (1886-1968) formed the Tri-Continental Corporation in 1917. This

company introduced the first windshield wiper, Rain Rubber, for the slotted, two-piece

windshields found on many of the automobiles of the time. Today Trico Products is one of

the world's leading manufacturers of windshield wiping systems, windshield wiper blades

and refills, with wiper plants on five continents.[citation needed] Bosch has the world's

biggest windscreen wiper factory in Tienen, Belgium, which produces 350,000 wiper blades

every day.

Inventor William M. Folberth applied for a patent for an automatic windscreen wiper

apparatus in 1919, which was granted in 1922. It was the first automatic

mechanism.[clarification needed] Trico later settled a patent dispute with Folberth and

purchased Folberth's Cleveland company, the Folberth Auto Specialty Co. The new vacuum-

powered system quickly became standard equipment on automobiles, and the vacuum

principle was in use until about 1960. In the late 1950s, a feature common on modern

vehicles first appeared, operating the wipers automatically for two or three passes when the

windshield washer button was pressed, making it unnecessary to manually turn the wipers on

as well. Today, an electronic timer is used, but originally a small vacuum cylinder

mechanically linked to a switch provided the delay as the vacuum leaked off.

1.1.1 INTERMITTENT WIPERS

The inventor of intermittent wipers might have been Raymond Anderson who, in

1923, proposed an electro-mechanical design. (US Patent 1,588,399). In 1958, Oishei et al.

filed a patent application describing electro-mechanical, thermal and hydraulic designs. (US

Patent 2,987,747). Then in 1961 John Amos, an engineer for the UK automotive engineering

company Lucas Industries, filed in the UK the first patent application for a solid-state

electronic design. (See US patent 3,262,042).

In 1963, another form of intermittent wiper was invented by Robert Kearns, an



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engineering professor at Wayne State University in Detroit, Michigan.The road to his

intermittent wipers began earlier, on his wedding night in 1953, when an errant champagne

cork shot into Kearn's left eye, which eventually went almost completely blind. Nearly a

decade later, Kearns was driving his Ford Galaxie through a light rain, and the constant

movement of the wiper blades irritated his already troubled vision. He got to thinking about

the human eye, which has its own kind of wiper, the eyelid, that automatically closes and

opens every few seconds. Finally in 1963, Kearns put his idea into action, building his first

intermittent wiper system using off-the-shelf electronic components. Kearns showed it to the

Ford Motor Company, and proposed manufacturing the design.

In the Kearns design, the interval between wipes was determined by the rate of

current flow into a capacitor. When the charge in the capacitor reached a certain voltage, the

capacitor was discharged, activating the wiper motor for one cycle. After extensive testing,

Ford executives decided to offer a design similar to Kearns’ intermittent wipers as an option

on the company's Mercury line, beginning with the 1969 models. Kearns and Ford became

involved in a multi-year patent dispute that eventually had to be resolved in court. A

fictionalized version of the Kearns invention and patent lawsuit was used for the 2009 film

Flash of Genius, which is billed as "based on the true story", but does not claim to be

historically accurate in all respects.In March 1970, Citroën introduced rain-sensitive

intermittent windscreen wipers on their SM model. When the intermittent function was

selected, the wiper would make one swipe. If the windscreen was relatively dry, the wiper

motor drew high current, which set the control circuit timer to delay the next wipe longest. If

the motor drew little current, it indicated that the glass was wet, setting the timer to minimize

the delay.

1.1.2 AUTOMATED RAIN SENSING WIPERS

We have pleasure in introducing our new project ―AUTOMATIC RAIN

OPERATED WIPER‖, which is fully equipped by sensors circuit and wiper motor. It is a

genuine project which is fully equipped and designed for Automobile vehicles.



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The Automatic rain operated wiper system is a fully automation project.

This is an era of automation where it is broadly defined as replacement of manual effort by

mechanical power in all degrees of automation. The operation remains an essential part of the

system although with changing demands on physical input as the degree of mechanization is

increased.

Degrees of automation are of two types, viz.

• Full automation.

• Semi automation.

In semi automation a combination of manual effort and mechanical power is required

whereas in full automation human participation is very negligible.

Windshield wipers, which have been standard equipment on most vehicles since 1916, were

developed to improve visibility during inclement weather. For nearly 100 years, drivers

operated the wipers with manual controls mounted on the dashboard. Today, technology has

made possible motorized windshield wipers that automatically recognize a developing

visibility problem and clear the glass before the driver can react to the problem.

The term ―rain-sensing wipers‖ is commonly used for a system designed to clear the

windshield of rain, snow, and debris without driver intervention. The system is programmed

to automatically activate and alter the speed and rate of the wiper blades to keep outward

visibility unobstructed at all times. A rain-sensing wiper system does not clean the windshield

any better than a manual system; it simply monitors outward visibility and automatically

activates the wipers.

Rain-sensing wipers are offered as standard equipment or as an inexpensive factory option on

many new cars, light trucks and SUVs. There are also many systems offered by aftermarket

suppliers. The wipers are easy to install; with just a single optical component, the technology

can easily be adapted to any vehicle with electric wipers. Because they increase driving

safety while reducing driver distraction and workload, rain-sensing wipers are a worthwhile

improvement to any vehicle.



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1.2 LITERATURE SURVEY

Automatic wipers with mist control

Ashik K.P1, A.N.Basavaraju2 1Research scholar, Dept. of Mechanical Engg., R.V College

of Engineering, Bangalore -560059, 2Head , Dept. of Automobile Engg ., Malnad College of

Engineering, Hassan-573202

ABSTRACT

This paper illustrates Automatic wipers with mist control. In modern days, the accidents are

most common in commercial vehicles. One of the reasons for these accidents is formation of

the mist inside the vehicle due to heavy rain. In rainy seasons for commercial vehicles, the

wiper on the windshield has to be controlled by the driver himself, which distracts his

concentration on driving. Also when the rain lasts for more time (say for about 15 minutes)

the formation of mist on the wind shield is also hinders the visibility of the driver and makes

driving difficult. The main aim of the project is to prevent the distractions to the driver of a

truck or bus. The rain intensity is measured by the set of sensors placed in the beaker at the

predetermined levels. The level of the water in the beaker decides the rain intensity and the

same will be sensed by each set of sensors and passes the signals corresponding to the level

of water in a beaker to microcontroller. Depending on the rain intensity microcontroller

controls the speed of the wiper motor. The principle of conductance is used for the working

of external and the internal sensors. The programmed microcontroller is used to actuate

external and internal wiper motors.

CONCLUSION

The concept of Automatic Wipers with Mist Control has been implemented successfully.

After the experimental setup the wiper motor was tested for all the following conditions

drizzling, heavy rain, medium rain. The test have been conducted under mist on the wind

shield. The mist has been removed successfully from the wind shield. By the uses of

automatic wipers one can drive the commercial vehicles without any distractions to operate

the wipe. Use of internal wipers ensures good visibility to the driver, prevents accidents.



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Smart Wiper Control System

N. M. Z. Hashim1, S. H. Husin2, A. S. Ja’afar3, N. A. A. Hamid4

1,2,3,4 Faculty of Electronics & Computer Engineering, Universiti Teknikal Malaysia

Melaka, Hang Tuah Jaya, 76100 Durian Tunggal, Melaka Malaysia

ABSTRACT

Wiper is an essential component that used to wipe raindrops or any water from the

vehicle’s windscreen. The previous system used to activate the wiper manually and the

process of pulling up the wiper is difficult to be handled. Thus, this system is proposed to

solve these problems. The objectives of this project are to upgrade the older cars system by

providing automatic wiping system, to improve the system by using sensor with actuator and

to design a basic program that will fully operate with the system. The concept of this

proposed wiper system is similar with other existing conventional wiper. In spite of removing

water from windscreen, this system also will be upgraded to an automatic control system by

using a Peripheral Interface Controller (PIC) 16F877A controller and water sensor. As the

conclusion for the project, the results shows all the aim objectives are successfully achieved.

The wiper system was well functionally according the water condition from the outside of a

car. This project showed a contribution on the design of the automatic wiper system for the

future research in this same field. It is recommended that the system to have a study on the

wiper material that been used to make a wiper because the driver at hot and climate country

are facing the problems regards to the wiper material

CONCLUSION

As the conclusion for the project, the results shows all the aim objectives are successfully

achieved. The wiper system was well functionally according the water condition from the

outside of a car. This project showed a contribution on the design of the automatic wiper

system for the future research in this field. For the future improvement, it is recommended

the system to have literature review on the material been used as the wiper, because the

material used is still has a problem in the procure issues especially for the hot and climate

country. Other suggestion for designing automatic push up wiper for future research and

improvement is about the design stand for the wiper.



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Automatic Wiper System

Shantanu Dharmadhikari1, Naeem Tamboli2, Nilesh Gawali3, Prof. N. N. Lokhande4

1,2,3,4Department of Instrumentation and Control Engg, Pravara Rural Engineering College,

Loni

ABSTRACT

In this paper, we present the automatic wiper system used to detect rainfall and activate

automobile windshield wipers without driver interaction. The system was developed to

reduce driving distractions and allow drivers to focus on main task of driving. The distraction

eliminated with the development of this system is the manual adjustment of wipers when

driving in precipitation. The few seconds that a driver takes their attention off the road to

adjust a knob while driving in poor weather conditions could potentially lead to car accidents.

The system uses a combination of impedance and piezo-electric sensors to detect rain and its

intensity. The system contains a microcontroller that takes in the input signals from the

sensors and controls the operation of the windshield wipers based on those input signals.

CONCLUSION

In conclusion, the automated windshield wiper system was designed, developed, and

demonstrated to detect rain and actuate the automobile windshield wipers based on the

intensity of that rain. The demonstration is able to simulate the operation of the system as if

installed in an automobile. The team was able to successfully complete the project and

satisfactorily meet the proposal goal of automating the driver’s response to rain within the

specified amount of time of 500 milliseconds. Though the system functioned as desired, in

retrospect then I would have selected different design approaches. After noticing that more

accuracy was required from the IR sensor to adequately detect the intensity of rain the team

would have selected a more applicable IR sensor.



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An Efficient Low Cost Wiper System for Autonomous Vehicle

N.Prabhakaran#1, Purushothaman Surendran*2 #Research Associate, School of

Electronics Engineering VIT University, Vellore, Tamil Nadu, India

ABSTRACT

The traditional wiper system requires driver’s attention to switch on the wiper system during

precipitation. Whereas in traffic condition, driver should not be diverted by manual

adjustment of switching the wiper system which may leads to accident. Probably 80% of

accidents are mainly due to distraction of driver. In this scenario we need to obtain an

automatic wiping on the wind screen during rain so as to avoid distraction of driver. The

existing automatic wiper system has false wiping just after the rainfall stops which can be

overcome by using proposed wiper system. Always just after the rainfall a few droplets on

the existing water sensor will be sustained until it is cleaned or inherently evaporated. These

water drops make a connection between two grid lines to occur false wiping. The advantage

of proposed automatic wiper system is compared with the water sensor of existing automatic

wiper system after rainfall. The proposed system in this paper is more accurate and

economically cheap which can be implemented in all low and middle level cars. In order to

avoid critical situation this automatic wiper system provides variable wiping speed based on

precipitation level. This automatic wiper system has low cost plate based water sensor,

ATMEGA8 microcontroller, MOSFET driver and wiper motor.

CONCLUSION

In the paper, plated based water sensor is evaluated on both rainfall and after rainfall

condition to obtain accurate result without false wiping under different scenarios. This system

is developed with low cost high performance electronic components to fit in all low cost

vehicles. The cost to implement is approximately 7$, which is less the any other wiping

system in the vehicles. A vertical/horizontal placement of plates give better result compare to

any another arrange of plates. The copper/aluminum plates can be fixed on to plastic board

and affix on the vehicles instead of placing directly on the windshield



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Semi-Automatic Rain Wiper System

Tapan S Kulkarni1, Harsh S Holalad2 1Dept of Automobile Engg, B V Bhoomaraddi College

of Engg & Tech Hubli 2 Dept of Electrical and Electronics Engg, B V Bhoomaraddi College

of Engg & Tech Hubli

ABSTRACT

The paper deals with a simple design of a Semi- Automatic Rain Wiper System. The system

is semi automatic because it has to be actuated for the first time. The system is developed

using 8051 microcontroller. The principle revolves around the rate of flow of water in a cup.

Corresponding to the rate of flow of water and the volume of the water, three levels of wiper

speeds have been achieved.

CONCLUSION

The tabletop model of semi-automatic rain wiper system has worked successfully at three

different stages of rain intensities. Also the cost of semi-automatic rain wiper system is INR

1080 only which can be easily implemented in all the present economic class vehicles. The

cup sensor is placed under the hood and thus does not affect the aesthetic of the vehicle.



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Intelligent Rain Sensing using Automatic Wiper System

Sonali B. Madankar, Dr. Milind M. Khanapurkar, Dept of CSE, Professor, Dept of ECE,

G.H. Raisoni College of Eng Nagpur-440016, India

ABSTRACT

Over the past two decades, the automotive industry has aggressively researched ways to

exploit modern computing and electronic advances in the development of safety, reliability,

and entertainment technologies for vehicles. With drivers exposed to an ever increasing

number of distractions, automatic rain-sensing wiper systems become an even more

appealing feature, as they work to minimize the time the driver must take his/her hands off

the wheel. Most traditional systems offer intermittent as well as variable speed operation. The

traditional wiper system however requires driver constant attention in adjusting the wiper

speed .Traditional windshield wiper speed constantly varies according to time and vehicle’s

speed. Because the manual adjustment of the wiper distracts driver's attention, which may be

a direct cause accidents. This is review paper for automatic wier in various method and also

explain the basic skeleton for adjust speed of wiper automatically cording to the amount of

water on the windshield and in addition with also in advance removal of moisture inside the

car while raining. The system activates the wiper to operate in full automatic mode and detect

moister using CAN technology.

CONCLUSION

We have to developed an automatic wiper control system which is improved version of

intermittent wiper system. This wiper system reduce cumbersome wiper operation and

improve driver’s level comfort.It will give a new dimension of comfort and aid to the drivers

who work at night and traffic prone areas where they already have to concentrate on brakes

and clutch. The removal of controlling the wipers during rain will provide them much ease

and help them concentrate on the basic ABC (accelerator, brake and clutch) of driving. Our

system features high accuracy, high sensitivity, and noncontact measurement. The system are

used as component in home automation system because it can detect a sudden rain and notify

people in the house.



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Design & Fabrication of Rain Operated Wiper Mechanism using

Conductive Sensor Circuit

K. V. Viswanadh Ch. Siva Sankara Babu J. Leela Krishna A. Lala Bahadur

Assistant Professor, Department of Mechanical Engineering Lakireddy Bali Reddy

College of Engineering Mylavaram, Andhra Pradesh, India

ABSTRACT

This is an era of automation where it is broadly defined as replacement of manual effort

by mechanical power in all degrees of automation. Now a day’s almost all the automobile

vehicles are being atomized in order to reduce human efforts. The AUTOMATIC RAIN

OPERATED WIPER system is a fully automation project. This is a genuine project

which is designed for automobile vehicles and is fully equipped by sensor circuit and

wiper motor. This project work includes design and development of a control system

based on electronically controlled automotive rain operated motor called AUTOMATIC

RAIN OPERATED WIPER.

CONCLUSION

And finally we conclude that, the wind screen wiper which we had fabricated with the

main theme of maintaining automation by using conductive sensor to the required extent

is a modification to the existing wind screen wiper which were been using in the four

wheelers. And therefore, implementation of this modified wind screen wiper helps

in reducing human effort, free from wear adjustment and operating principle is very easy

which were the problems being faced with the existing wind screen wiper. Presently the

mode of power source used in our project is a battery which is a replaceable power

source. Here we have used the battery which is a non-conventional source of power,

keeping the scope of resources in mind this can be easily replaced by the conventional

power sources like solar panels.



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CHAPTER 2

AUTOMATION

2.1 INTRODUCTION

It is the use of control systems and information technologies to reduce the need for

human work in the production of goods and services. In the scope of industrialization,

automation is a step beyond mechanization. Whereas mechanization provided human

operators with machinery to assist them with the muscular requirements of work, automation

greatly decreases the need for human sensory and mental requirements as well. Automation

plays an increasingly important role in the world economy and in daily experience.

Automation has had a notable impact in a wide range of industries beyond manufacturing

(where it began). Once-ubiquitous telephone operators have been replaced largely by

automated telephone switchboards and answering machines. Medical processes such as

primary screening in electrocardiography or radiography and laboratory analysis of human

genes, sera, cells, and tissues are carried out at much greater speed and accuracy by

automated systems. Automated teller machines have reduced the need for bank visits to

obtain cash and carry out transactions. In general, automation has been responsible for the

shift in the world economy from industrial jobs to service jobs in the 20th and 21st centuries.

2.2 NEED FOR AUTOMATION

Automation can be achieved through computers, hydraulics, pneumatics, robotics, etc., of

these sources, pneumatics form an attractive medium for low cost automation. Automation

plays an important role in automobile.

Nowadays almost all the automobile vehicle is being atomized in order to product the human

being. The automobile vehicle is being atomized for the following reasons.

• To achieve high safety



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• To reduce man power

• To increase the efficiency of the vehicle

• To reduce the work load

• To reduce veihcle accident

• To reduce the fatigue of drivers

• To high responsibility

• Less maintainence cost

2.3 ADVANTAGES

The main advantages of automation are:

• Replacing human operators in tasks that involve hard physical or monotonous work.

• Replacing humans in tasks done in dangerous environments (i.e. fire, space,

volcanoes, nuclear facilities, underwater, etc.)

• Performing tasks that are beyond human capabilities of size, weight, speed,

endurance, etc.

• Economy improvement: Automation may improve in economy of enterprises, society

or most of humanity. For example, when an enterprise invests in automation, technology

recovers its investment; or when a state or country increases its income due to automation

like Germany or Japan in the 20th Century.

• Reduces operation time and work handling time significantly.



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2.4 DISADVANTAGES

The main disadvantages of automation are:

• Unemployment rate increases due to machines replacing humans and putting those

humans out of their jobs.

• Technical Limitation: Current technology is unable to automate all the desired tasks.

• Security Threats/Vulnerability: An automated system may have limited level of

intelligence, hence it is most likely susceptible to commit error.

• Unpredictable development costs: The research and development cost of automating a

process may exceed the cost saved by the automation itself.

• High initial cost: The automation of a new product or plant requires a huge initial

investment in comparison with the unit cost of the product, although the cost of automation is

spread in many product batches of things

2.5 AUTOMATION TOOLS

Engineers now can have numerical control over automated devices. The result has

been a rapidly expanding range of applications and human activities. Computer-aided

technologies (or CAx) now serve the basis for mathematical and organizational tools used to

create complex systems. Notable examples of CAx include Computer-aided design (CAD

software) and Computer-aided manufacturing (CAM software). The improved design,

analysis, and manufacture of products enabled by CAx has been beneficial for industry.

Information technology, together with industrial machinery and processes, can assist in the

design, implementation, and monitoring of control systems. One example of an industrial

control system is a programmable logic controller (PLC). PLCs are specialized hardened

computers which are frequently used to synchronize the flow of inputs from (physical)



15

sensors and events with the flow of outputs to actuators and events.

2.6 TYPES OF AUTOMATION

Discrete control (on/off)

One of the simplest types of control is on-off control. An example is the thermostats used on

household appliances. Electromechanical thermostats used in HVAC may only have

provision for on/off control of heating or cooling systems. Electronic controllers may add

multiple stages of heating and variable fan speed control.

Sequence control, in which a programmed sequence of discrete operations is performed,

often based on system logic that involves system states. An elevator control system is an

example of sequence control.

Continuous control

The advanced type of automation that revolutionized manufacturing, aircraft,

communications and other industries, is feedback control, which is usually continuous and

involves taking measurements using a sensor and making calculated adjustments to keep the

measured variable within a set range. Moreover, it can be understood as the relation of two

variables, one for the "x" axis and a second for the "y" axis. If the value of "y" increases, then

the value on the "x" axis will also increase, and vice versa,

Open and closed loop

All the elements constituting the measurement and control of a single variable are called a

control loop. Control that uses a measured signal, feeds the signal back and compares it to a

set point, calculates and sends a return signal to make a correction, is called closed loop

control. If the controller does not incorporate feedback to make a correction then it is open

loop.Loop control is normally accomplished with controller. The theoretical basis of open

and closed loop automation is control theory.

https://en.wikipedia.org/wiki/HVAC

https://en.wikipedia.org/wiki/Sensor



16

Sequential control and logical sequence or system state control

Sequential control may be either to a fixed sequence or to a logical one that will

perform different actions depending on various system states. An example of an adjustable

but otherwise fixed sequence is a timer on a lawn sprinkler.

States refer to the various conditions that can occur in a use or sequence scenario of the

system. An example is an elevator, which uses logic based on the system state to perform

certain actions in response to its state and operator input. For example, if the operator presses

the floor n button, the system will respond depending on whether the elevator is stopped or

moving, going up or down, or if the door is open or closed, and other conditions. An early

development of sequential control was relay logic, by which electrical relays engage

electrical contacts which either start or interrupt power to a device. Relays were first used in

telegraph networks before being developed for controlling other devices, such as when

starting and stopping industrial-sized electric motors or opening and closing solenoid valves.

Using relays for control purposes allowed event-driven control, where actions could be

triggered out of sequence, in response to external events. These were more flexible in their

Figure No 2.1 State Abstraction

This state diagram shows how UML can be used for designing a door system that can only be

opened and closed

https://en.wikipedia.org/wiki/File:Finite_state_machine_example_with_comments.svg





17

response than the rigid single-sequence cam timers. More complicated examples involved

maintaining safe sequences for devices such as swing bridge controls, where a lock bolt

needed to be disengaged before the bridge could be moved, and the lock bolt could not be

released until the safety gates had already been closed.

The total number of relays, cam timers and drum sequencers can number into the hundreds or

even thousands in some factories. Early programming techniques and languages were needed

to make such systems manageable, one of the first being ladder logic, where diagrams of the

interconnected relays resembled the rungs of a ladder. Special computers called

programmable logic controllers were later designed to replace these collections of hardware

with a single, more easily re-programmed unit.

In a typical hard wired motor start and stop circuit (called a control circuit) a motor is started

by pushing a "Start" or "Run" button that activates a pair of electrical relays. The "lock-in"

relay locks in contacts that keep the control circuit energized when the push button is

released. (The start button is a normally open contact and the stop button is normally closed

contact.) Another relay energizes a switch that powers the device that throws the motor

starter switch (three sets of contacts for three phase industrial power) in the main power

circuit. Large motors use high voltage and experience high in-rush current, making speed

important in making and breaking contact. This can be dangerous for personnel and property

with manual switches. The "lock in" contacts in the start circuit and the main power contacts

for the motor are held engaged by their respective electromagnets until a "stop" or "off"

button is pressed, which de-energizes the lock in relay.

Commonly are added to a control circuit. Suppose that the motor in the example is powering

machinery that has a critical need for lubrication. In this case an interlock could be added to

insure that the oil pump is running before the motor starts. Timers, limit switches and electric

eyes are other common elements in control circuits. Solenoid valves are widely used on

compressed air or hydraulic fluid for powering actuators on mechanical components. While

motors are used to supply continuous rotary motion, actuators are typically a better choice for

intermittently creating a limited range of movement for a mechanical component, such as

moving various mechanical arms, opening or closing valves, raising heavy press rolls,

applying pressure to presses.



18

CHAPTER 3

WINDSCREEN WIPER

A Windscreen wiper or Windshield wiper is a device used to remove rain and debris

from a windscreen or windshield. Almost all motor vehicles, including trains, aircraft and

watercraft, are equipped with such wipers, which are usually a legal requirement.

A wiper generally consists of an arm, pivoting at one end and with a long rubber blade

attached to the other. The blade is swung back and forth over the glass, pushing water from

its surface. The speed is normally adjustable, with several continuous speeds and often one or

more "intermittent" settings. Most automobiles use two synchronized radial type arms, while

many commercial vehicles use one or more pantograph arms.

3.1 HISTORY

Fig. 3.1: Windscreen Wiper

The inventor Mary Anderson is credited with devising the first operational windshield wiper

in 1903. In Anderson's patent, she called her invention a "window cleaning device" for

electric cars and other vehicles. Operated via a lever from inside a vehicle, her version of

windshield wipers closely resembles the windshield wiper found on many early car models.

Anderson had a model of her design manufactured, then filed a patent (US 743,801) on June

18, 1903 that was issued to her by the US Patent Office on November 10, 1903.

Irish born inventor James Henry Apjohn (1845–1914) devised a method of moving two

http://en.wikipedia.org/wiki/File:Scheibenwischer_eines_IFA,_Bj._1954_(2008-07-12).jpg





19

brushes up and down on a vertical plate glass windscreen in 1903. This was patented in the

UK.

In April 1911, a patent for windscreen wipers was registered by Sloan & Lloyd Barnes,

patent agents of Liverpool, England, for Gladstone Adams of Whitley Bay. The first designs

for the windscreen wiper are also credited to concert pianist Józef Hofmann, and Mills

Munitions, Birmingham who also claimed to have been the first to patent windscreen wipers

in England.

The company Oishei formed, the Tri-Continental Corporation, introduced the first windshield

wiper, Rain Rubber, for the slotted, two-piece windshields found on many of the automobiles

of the time. Today Trico Products is one of the world's leading manufacturers of windshield

wiping systems, windshield wiper blades and refills, with wiper plants on five continents

Bosch has the world's biggest windscreen wiper factory in Tienen, Belgium, which produces

350,000 wiper blades every day.

Inventor William M. Folberth applied for a patent for an automatic windscreen wiper

apparatus in 1919, which was granted in 1922. It was the first automatic mechanism. Trico

later settled a patent dispute with Folberth and purchased Folberth's Cleveland company, the

Folberth Auto Specialty Co. The new vacuum-powered system quickly became standard

equipment on automobiles, and the vacuum principle was in use until about 1960. In the late

1950s, a feature common on modern vehicles first appeared, operating the wipers

automatically for two or three passes when the windshield washer button was pressed,

making it unnecessary to manually turn the wipers on as well. Today, an electronic timer is

used, but originally a small vacuum cylinder mechanically linked to a switch provided the

delay as the vacuum leaked off.



20

3.2 INTERMITTENT WIPERS

In 1963, the first modern intermittent wipers were invented by Robert Kearns, an

engineering professor at Wayne State University in Detroit, Michigan. The road to

intermittent wipers began earlier, on his wedding night in 1953, when an errant champagne

cork shot into Kearn's left eye, which eventually went almost completely blind. Nearly a

decade later, Kearns was driving his Ford Galaxie through a light rain, and the constant

movement of the wiper blades irritated his already troubled vision. He got to thinking about

the human eye, which has its own kind of wiper, the eyelid, that automatically closes and

opens every few seconds. Finally in 1963, Kearns put his idea into action, building the first

intermittent wiper system using off-the-shelf electronic components. Kearns showed it to the

Ford Motor Company, and proposed manufacturing the design.

In the Kearns design, the interval between wipes was determined by the rate of current flow

into a capacitor. When the charge in the capacitor reached a certain voltage, the capacitor was

discharged, activating the wiper motor for one cycle. After extensive testing, Ford executives

decided to offer a design similar to Kearns’ intermittent wipers as an option on the company's

Mercury line, beginning with the 1969 models. Kearns and Ford became involved in a multi-

year patent dispute that eventually had to be resolved in court.

Kearns may not, in fact, have been the original inventor of the intermittent wiper concept.

John Amos, an engineer for the UK automative engineering company Lucas Industries, was

the first to file a patent for an intermittent wiper (US Patent #3,262,042, issued 1966), two

years before Kearns applied (US Patent #3,351,836, issued 1967). One notable difference is

that the Amos patent describes an electromechanical device, whereas Kearns proposed a

solid-state electronic circuit.

In March 1970, Citroën introduced rain-sensitive intermittent windscreen wipers on their SM

model. When the intermittent function was selected, the wiper would make one swipe. If the

windscreen was relatively dry, the wiper motor drew high current, which set the control

circuit timer to delay the next wipe longest. If the motor drew little current, it indicated that

the glass was wet, setting the timer to minimize the delay.



21

3.3 POWER

Fig. 3.2: Pneumatic Motor Drive in Train

Wipers may be powered by a variety of means, although most in use today are

powered by an electric motor through a series of mechanical components, typically two 4-bar

linkages in series or parallel.

Vehicles with air operated brakes sometimes use pneumatic wipers, powered by tapping a

small amount of pressurized air from the brake system to a small air operated motor mounted

on or just above the windscreen. These wipers are activated by opening a valve which allows

pressurized air to enter the motor.

Early wipers were often driven by a vacuum motor powered by manifold vacuum. This had

the drawback that manifold vacuum varies depending on throttle position, and is almost non-

existent under wide-open throttle, when the wipers would slow down or even stop. This

problem was overcome somewhat by using a combined fuel/vacuum booster pump.

Some cars, mostly from the 1960s and 1970s, had hydraulically driven wipers.

On the earlier Citroën 2CV, the windscreen wipers were powered by a purely mechanical

system, a cable connected to the transmission; to reduce cost, this cable also powered the

speedometer. The wipers' speed was therefore variable with car speed. When the car was

waiting at an intersection, the wipers were not powered, but a handle under the speedometer

allowed the driver to power them by hand.

http://en.wikipedia.org/wiki/File:Nahverkehrsmunseum-Triebwagen-431-DSC_6417.jpg





22

3.4 GEOMETRY

Most wipers are of the pivot (or radial) type: they are attached to a single arm, which

in turn is attached to the motor. These are commonly found on many cars, trucks, trains,

boats, airplanes, etc.

Another type of wiper design is pantograph-based (see Fig. 6, below), which are used on

many commercial vehicles, especially buses with large windscreens. Pantograph wipers

feature two arms for each blade, with the blade assembly itself supported on a horizontal bar

connecting the two arms. One of the arms is attached to the motor, while the other is on an

idle pivot. The pantograph mechanism, while being more complex, allows the blade to cover

more of the windscreen on each wipe. However, it also usually requires the wiper to be

"parked" in the middle of the windscreen, where it may partially obstruct the driver's view

when not in use. Some larger cars in the late '70s and early '80s, especially LH driver

American cars, had a pantograph wiper on the driver's side, with a conventional pivot on the

passenger side.

Mercedes-Benz pioneered a system called the Monoblade, based on cantilevers (see Fig. 5,

below), in which a single arm extends outward to reach the top corners of the windscreen,

and pulls in at the ends and middle of the stroke, sweeping out a somewhat 'M'-shaped path.

This way, a single blade is able to cover more of the windscreen, and displace the residual

streaks away from the center of the windscreen.



23

•

Figure. 3.3: Most common geometry found on vast majority of vehicles

Figure 3.4: Mercedes-Benz W114, W168, W169; VW Sharan, Honda Civic, some

minivans, some school buses, Peugeot 307

Figure. 3.5: SEAT Altea, SEAT León Mk2, SEAT Toledo Mk3

Figure. 3.6: VAZ-1111 Oka, Fiat Uno 1983–1995, 1990's Citroën Citroen AX

Figure. 3.7: Subaru XT, Mercedes-Benz W124, W201, W202, W210

Figure. 3.8: Buses, some school buses, Mercedes-Benz O305

http://en.wikipedia.org/wiki/File:Scheibenwischer1.svg


















































24

Figure. 3.9: MAN, Toyota FJ Cruiser, Jaguar E-type, MGB, MG Midget, Austin Healey

Sprite

Figure. 3.10: obsolete, found on some older firetrucks

Figure. 3.11: U.S. military wheeled vehicles, jeepneys, some school buses

Figure. 3.12: Like Fig. 3.3 but mirrored, Mercedes-Benz W140



























25

CHAPTER 4

SYSTEM OVERVIEW

4.1 PURPOSE OF DEVELOPMENT

In developing the automobile we intended to fulfill the following purpose:

1. Convenience- To dispense with troublesome wiper operation needed when rainfall

condition change or when driving condition change including the car speed and entry to or

exit from tunnels.

2. Comfort- To operate the wiper with respose to change in rainfall and driving

condition. Thus keeping the windshield clear.

3. Installation- System is easy to install.



26

4.2 SYSTEM CONFIGURATION

Fig 4.1: System configuration

The above figure shows the system configuration. The automatic wiper system consist of a

optical rain sensor installed on hood and a controller mounted inside. The controller is

connected to the existing wiper switch and motor. Since the automatic wiper is an extension

to the existing wiper system, it is easy for driver to control. The function of the sensor are

outlined below:

1. Rain Sensor- (Rain drop detection function) The rain sensor detect the rain drop by

sensing the change in light intensity when rain drops cross near infrared sensing between the

light emitting and light sensitive element.

2. Controller- The controller have following three conditions

• Semi Automatic- when the wiper switch is set to intermittent close position, the



27

wipers move once and then moves at intervals automatically controlled. The interval can

range from low (continuous) operation to high (continuous) operation according to rain fall.

When the wiper switch is set to low or high the wiper works as a conventional wiper.

• Washer Interlock Function- when washer switch is turned on, the wiper moves. When

it is turned off, the wiper will stop after two wiping cycles.

• Fail Safe Function- it is assured that the wiper operates at 6 seconds intervals when

the rain drop detection is disabled because the sensing beam iscompletely blocked by dust,

snow or other matter struck to the sensor.



28

CHAPTER 5

WORKING OF THE CIRCUIT

5.1 PROJECT SPECIALITIES

This project is very useful for every car. When we drive car, we do not know, whether

rain water reached up to the level that we could see any more. Such a project automatic turn

the wiper . Thus it saves the motor from burning as well as prevents current leakage and

increase the battery life.

5.1.1 PRINCIPLE OF WORKING

Rain will be detected through the circuit provided in the driver PCB when drops of

water fall on the sensor PCB located in front of the windshield provided in the vehicles. The

sensor PCB should be connected with the driver PCB.

When drops of rain water falls on the sensor PCB the base of T1 is getting connected to the

positive supply line. As the result T1 & T2 are switched on so that the relay R on the wiper

motor with the help of 9V battery. The motor is driven by the 12V battery and drives the link

rod through linkage and the shaft rotates. On this shaft the blade is mounted and locked by a

nut.

According to amount of rain pours on the sensing element, the circuit makes the motor to

rotate at reasonable speed. When the amount of rain drop is more the speed of the motor must

be in high to wash out the rain completely from the windshield. If the amount of rain is low,

less speed is sufficient for the clear vision of driver on the road.



29

Figure 5.1 Block diagram of wiper system

5.2 TECHNICAL DESCRIPTION AND WORKING:-

Generally we use manual switch to control wiper motor to start wiper to swipe water on

the windshield. While swipe water, it is difficult to know whether the rain water level has

reached the danger mark or not. We are giving here a project which gives a automatic signal

to wiper motor when the water level reaches danger mark and the swipe motor goes on

running as long as the rain water level is above the danger mark. The motor stops only when

the rain water level comes below the danger mark. The circuit employs one integrated circuit

IC 555. Whenever the metal plate [metal rain water sensor] comes in contact with water, pin

no. 2 of the IC is triggered. As a result the output of IC, which available through pin no.3 is

fed to the motor to start wiping the water on the wind screen. The circuit is an example of a

stable operation which charges and discharges through C2 [.1 mfd] R1 10K or variable

resistance VR2 47K. The duty cycle of IC can be varied through the preset VR2 22K. This

preset connected to pin no. 4 of C also performs the function of OFF/ON. The circuit operates

on a 9 V DC.

VEHICLE MIRROR

SENSOR

CONTROL

UNIT

RELAY

WIPER

MOTOR

BATTERY



30

5.2 Figure Number : Layout of wiper system



31

CHAPTER 6

PARTS LIST

6.1 FOR AUTOMATIC WIPER SPEED MOTER CONTROLLER

1. IC 555 1

2. IC BASE 1

3. SPEAKER 8 OHM 1

4 CAPACITOR 100MFD/16V [C1,C2,C3] 1

RESISTERS

R1 10K 1

VR1 47K 1

VR2 22K 1

METAL PLATES 2



32

CHAPTER 7

CIRCUIT

7.1 AUTOMATIC WIPER CONTROL SYSTEM

Fig.: 7.1 Automatic Wiper Control System Circuit



33

CHAPTER 8

ELECTRONIC COMPONENT

8.1 RESISTANCE

It is a property of material to oppose the current flow in any conductor. It is measured

in Ohms. No conductor is 100% efficient to control the flow of current. Almost all type of

conductor material represent a certain amount of resistance. For this purpose we use lumped

resistance to control the flow of current. These resistance are of two type.

1. Fixed Resistance

2. Variable Resistance.

In fixed resistance the value is fixed and it can’t be change. Variable resistance can be

adjusted to any required value by a adjustable knob. Variable resistance are further divided

into three type

1. Carbon composition

2. Wire-wound

3. Special type

The most common type of resistance used in our project are carbon type. It value is normally

indicated by color band on its body. Each resistance has four color rings. One of the ring on

either side will be Gold or Silver. This is the fourth ring on the resistance and indicate the

tolerance. Other three ring will give the value of the resistance. The first ring gives the 1st

Digit. The second Ring gives the second digit. The third ring give the numbers of zero to be

placed after the digit. For example if the resistance has the following bands on it say Red,

Violet, Orange, and Gold. Reading the value of resistance with the help of colour code, its

value comes to be 27,000 Ohms or 27 K Ohms with tolerance 5%. Size of the resistance

indicates its power rating. Bigger the size more power rating. The table given below gives us

the colour code for the value of Resistance in Ohms.



34

STANDARD COLOUR CODE SYSTEM COLOUR DIGIT

Black----------------------------------------------------------------------0

Brown --------------------------------------------------------------------1

Red -----------------------------------------------------------------------2

Orange -------------------------------------------------------------------3

Yellow -------------------------------------------------------------------4

Green --------------------------------------------------------------------5

Blue ----------------------------------------------------------------------6

Violet --------------------------------------------------------------------7

Grey ----------------------------------------------------------------------8

White --------------------------------------------------------------------9

Silver -----------------------------------------------------------------+-10%

Golden ---------------------------------------------------------------+-5%

Figure Number 8.1 : Resister



35

8.2 CAPACITORS

It is a electronic component whose job is to store charge and after some interval to reales

it. It consists of two plate placed near to each other without touching. If a battery is connected

to these plate , positive of battery to one plate and -ve of battery to the another plate, then

electron from the battery will be attached from the plate to the positive of the battery. In this

position if battery is disconnected than one plate will be left with excess of electron while

other plate will be having the shortage of electrons. Thus there is a difference of potential

between these two plates and these plates act as capacitor. Capacitors are of two type:-

1. Fixed type [like ceramic, polyester, electrolyte.]

2. Variable type [like gang condenses trimmers etc.]

Fig.: 8.2 Capacitor

In a fix ed type capacitor there are two leads and its value is written on its body. In variable

type condenser there are three leads. Electrotype capacitor is polarity type and its terminals

are marked as positive and negative. Make sure that they are connected in circuit in proper

polarity. The value of the capacitor is measured in fared and denoted by the symbol F. Small

value of capacitor are measured in the Pico fared and denoted by PF.

Charge separation in a parallel-plate capacitor causes an internal electric field. A

dielectric (orange) reduces the field and increases the capacitance



36

A simple demonstration of a parallel-plate capacitor .A capacitor consists of two conductors

separated by a non-conductive region. The non-conductive region is called the. In simpler

terms, the dielectric is just an electrical insulator.

8.2.1 THEORY OF OPERATION

Figure No:8.3 Operation of capacitor.

Examples of dielectric media are glass, air, paper, vacuum, and even 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 any external electric

field. The conductors thus hold equal and opposite charges on their facing surfaces, and the

dielectric develops an electric field. 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. 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:

Because the conductors (or plates) are close together, the opposite charges on the conductors

attract one another due to their electric fields, allowing the capacitor to store more charge for

a given voltage than if the conductors were separated, giving the capacitor a large

capacitance.Sometimes charge build-up affects the capacitor mechanically.

https://en.wikipedia.org/wiki/File:Capacitor_schematic_with_dielectric.svg






37

8.3 KEY SWITCH

Switches are used to supply the power to a circuit. When it is pressed it makes the

current to flow through it. When the switch is released the current stops flowing. Thus a

switch is a mechanical part which controls the flow of current in a circuit. A switch is rated

according to

1. The maximum current it can carry.

2. Its working voltage

Figure : 8.4 Key Switch

Switches are of the following types.

1.Push Button Switches

2. Rocker Switches [Toggle]

3. Key Switches

4. Rotary Switches

5. Sliding Type Generally a switch consists of a fixed and moving contact but there are

switches which have several contacts in one unit.



38

8.4 TRANSISTOR

It is a solid state semi-conductor device. It is used in electronics for amplification or

switching. A transistor has three terminals.

1. Collector 2. Base 3. Emitter

Electrons are emitted from the emitter and collected on the collector of the transistor. Third

terminal is called base and it acts as a control element. The function of these entire three

terminals depends upon the supply voltage applied to these terminals. Each transistor has a

number marked on its body. This number has its own specification. There are two types of

transistors.

1. NPN 2. PNP

Figure.: 8.5 Transistor

NPN TRANSISTOR

In this type of transistor when positive voltage is given to the base current starts flowing

through the collector to the emitter circuit. The current flowing through the base circuit

casuses a much more current to pass through the emitter/collector circuit. There is current

gain and this gain is measured in beta.

PNP TRANSISTOR

It functions in similar way that of NPN transistor accept that it has a negative voltage on its

collector and positive voltage on its emitter. In other words its supply voltage and biasing are

quite opposite to the NPN transistor.



39

8.5 TRANSFORMER

There are different types of transformers depending upon the application just as step-

up, step-down, sound output, frequency matching and amplifier driver etc. Transformer

consists of two coils wound over a core in a such a way that both coils are magnetically

coupled. These coils are called primary and secondary winding. The core of the transformer

consists of a number of thin plates leminated from each other. These plates are made of

hardened silicon steel. The coil of the transformer are wound over a plastic bobbin or a

former made of hard paper. The winding of the transformer consist of number of turns of

enamelled copper wires. To prevent the short circuit between these windings a strip of

insulation paper is placed between each layer of the winding.

In a transformer the coupling between the coils makes a path for the magnetic flux to link

both the coils. Because of high permeability of the core iron. the flux path is only in the iron

and thus it links both the windings. When coupling is not good there is some leakage of flux

and it does not link both the coils. Ferrite core is used in high frequency transformer.

8.6.1 IDEAL TRANSFORMER

For simplification or approximation purposes, it is very common to analyze the

transformer as an ideal transformer model as presented in the two images. An ideal

transformer is a theoretical, linear transformer that is lossless and perfectly coupled; that is,

there are no energy losses and flux is completely confined within the magnetic core. Perfect

coupling implies infinitely high core magnetic permeability and winding inductances and

zero net magnetomotive force.

Ideal transformer connected with source VP on primary and load impedance ZL on

secondary, where 0 < ZL < ∞.

A varying current in the transformer's primary winding creates a varying magnetic flux in the

core and a varying magnetic field impinging on the secondary winding. This varying

magnetic field at the secondary induces a varying electromotive force (EMF) or voltage in the

secondary winding. The primary and secondary windings are wrapped around a core of



40

infinitely high magnetic permeability so that all of the magnetic flux passes through both the

primary and secondary windings. With a voltage source connected to the primary winding

and load impedance connected to the secondary winding, the transformer currents flow in the

indicated directions. (See also Polarity.)

Ideal transformer and induction law

According to Faraday's Law, since the same magnetic flux passes through both the primary

and secondary windings in an ideal transformer,a voltage is induced in each winding,

according to eq. (1) in the secondary winding case, according to eq. (2) in the primary

`winding case. The primary EMF is sometimes termed counter EMF. This is in accordance

with Lenz's law, which states that induction of EMF always opposes development of any

such change in magnetic field.

The transformer winding voltage ratio is thus shown to be directly proportional to the

winding turns ratio according to eq. (3).

According to the law of Conservation of Energy, any load impedance connected to the ideal

transformer's secondary winding results in conservation of apparent, real and reactive power

consistent with eq. (4).

Instrument transformer, with polarity dot and X1 markings on LV side terminal

The ideal transformer identity shown in eq. (5) is a reasonable approximation for the typical

commercial transformer, with voltage ratio and winding turns ratio both being inversely

proportional to the corresponding current ratio.

By Ohm's Law and the ideal transformer identity:

the secondary circuit load impedance can be expressed as eq. (6)

the apparent load impedance referred to the primary circuit is derived in eq. (7) to be equal to

the turns ratio squared times the secondary circuit load impedance.



41

8.6 COIL

Figure: 8.6 Coil

If a high resistance wire is wrapped over an insulator then it is called a wire wound

resistance. If in its place a wire with very negligible resistance is used then it is called coil. It

is measured in henry [H]. One thousand part of henry is called mili henry. In addition to the

resistance of the coil there is one more property called the inductance of the coil which play

very important part in its use. Some times due to this property coil is also called inductor.

Some time the coil is named according to the circuit where the coil has been used. Thus these

are called antenna coil [MW], oscillator coil and choke coil etc.

M 1. It offers some resistance in the path of AC.

M 2. It does not put any hindrance in the path of DC. At high frequency the coil offers more

hindrance to the current.

`

Figure Number 8.7 : Relay with transformer



42

8.9 IC 555

The 555 timer IC is an amazingly simple yet versatile device.It has been around now

for many years and has been reworked into a number of different technologies.The two

primary versions today are the original bipolar design and the more recent CMOS

equivalent.These differences primarily affect the amount of power they require and their

maximum frequency of operation they are pincompatible and functionally interchangeable.

The IC is available in either an 8-pin round TO3-style can or an 8-pin mini-DIP package.In

either case the pin connections are as follows:

Figure: 8.8 IC 555



43

1.Ground

2.Trigger input

3.Output

4.Reset input

5.Control voltage

6.Threshhold input

7.Discharge

8.15 to -15 volts in normal use.

The operations of 555 timer revolves around the three resistors that form a voltage divider

across the power supply.and two comparators connected to this voltage divider.The IC is

quiescent so as long the trigger input(pin2) remains at +Vcc and the threshhold input (pin6) is

at ground.Assume the rest input (pin4) is also at +Vcc and therefore inactive and the control

voltage input(pin5)is unconnected.Under these conditions the output(pin3)is at ground and

the discharge transistor(pin7)is turned on.Thus grounding whatever is connected to this pin.

The three resistors in the voltage divider all have the same value(5K in the bipolar version of

this IC)so the comparator reference voltages are 1/3 and 2/3 of the supply voltage,whatever

that may be.The control voltage input at pin 5 can directly affect this relationship.although

most of the time this pin is unused. The internal flip-flop changes state when the trigger input

at pin 2 is pulled down below +Vcc/3.When this occurs the output(pin3) changes state to

+Vcc and the discharge transistor (pin7)isturned off.The trigger input can now return to

+Vcc,it will not affect the state of the IC.

However,if the threshhold input(pin6)is now raised above(2/3)+Vcc.the output will return to

ground and the discharge transistor will be turned on again.When the threshhold input returns

to ground,the IC will remain in original state when we started this analysis. The easiest way

to allow the threshhold voltage(pin6)to gradually rise to(2/3)+Vcc is to connect it to a

capacitor is being allowed to charge through a resistor.In this way we can adjust the R and C

values for almost anytime interval we might want. The 555 can operate in either monostable

or astable mode,depending on the connections to and the arrangement of the external



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components.Thus,it can either produce a single pulse when triggered.or it can produce a

continuous pulse train as long as it remains powered.

8.7 RAIN SENSOR

A rain sensor or rain switch is a switching device activated by rainfall. There are

two main applications for rain sensors. The first is a water conservation device connected to

an automatic irrigation system that causes the system to shut down in the event of rainfall.

The second is a device used to protect the interior of an automobile from rain and to support

the automatic mode of windscreen wipers. An additional application in professional satellite

communications antennas is to trigger a rain blower on the aperture of the antenna feed, to

remove water droplets from the mylar cover that keeps pressurized and dry air inside the

wave-guide.

Figure 8.9 Rain Sensor



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8.5.2 AUTOMATIVE SENSORS

Figure no 8.10 operation of an optical rain sensor

In 1958, the Cadillac Motor ar Division of General Motors experimented with a

water-sensitive switch that triggered various electric motors to close the convertible top and

raise the open windows of a specially-built Eldorado Biarritz model, in case of rain. The first

such device appears to have been used for that same purpose in a concept vehicle designated

Le Sabre and built around 1950–51. For Model Year 1996, Cadillac once again equipped cars

with an automatic rain sensor; this time to automatically trigger the windshield wipers and

adjust their speed to conditions as necessary].The most common modern rain sensors are

based on the principle of total internal reflection: an infrared light is beamed at a 45-degree

angle into the windshield from the interior — if the glass is wet, less light makes it back to

the sensor, and the wipers turn on. Most vehicles with this feature have an "AUTO" position

on the stalk

https://en.wikipedia.org/wiki/File:Rain_sensor_en.svg





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CHAPTER 9

ADVANTAGES

The benefits of a rain-sensing wiper system are most obvious during inconsistent rain

or snow, when a standard wiper system requires constant attention by the driver to keep the

windshield clear. Under such conditions, the rain-sensing system adapts to periods of heavy

rain or snow and increases the speed of the wipers. During dry periods, when the windshield

is clear, the wipers completely stop. If other vehicles splash or spray water or debris on the

windshield, the rain-sensing system automatically intervenes by starting the wipers to keep

visibility unobstructed.

Rain sensing wipers allow the driver to simply activate the wipers once. The driver never has

to adjust the settings or speed of the wipers or turn them on and off with inconsistent

precipitation. It is especially beneficial while driving through varying degrees of traffic,

because the driver does not have to continually change the speed of the wipers.

Other advantages are as follows:-

• Low cost automation project.

• Free from wear adjustment.

• Less power consumption

• Operating Principle is very easy.

• Installation is simplified very much.

• To avoid other burnable interactions viz.… (Diaphragm) is not used.

• It is possible to operate Manually/automatically by proving On/Off switch.

• Sensor cost is very low due to conductive sensor



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9.1 HOW DO THEY INCREASE DRIVER SAFETY

Many collisions are caused by driver distractions. Rain-sensing wiper technology

allows the driver to activate the windshield wipers once, and then forget about them. The

windshield wipers must be re-activated, however, if the vehicle has been turned off and re-

started.



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CHAPTER 10

APPLICATIONS

1. Four wheeler application

2. Trucks

3. Buses

4. Trains

5. Airplanes

6. Ships



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COST ESTIMATION

• Glass Rs. 350.00

• Wiper Motor with linkages Rs. 1100.00

• Wiper blade Rs. 350.00

• Rain Sensor with accessories Rs. 1000.00

TOTAL Rs. 2800.00



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CONCLUSION

We have developed an optical automatic windshield wiper control which is an improved

version of the intermittent wiper systems. This wiper system reduces cumbersome wiper

operations and improves the driver’s level of comfort.

The rain sensor developed for the automatic wiper uses optics technology. The rain sensor

has been marked as a device suitable for use in harsh environments. Our optical system

features high accuracy, high sensitivity, and non contact measurement.

The rain sensor can also be used as a component in home automation systems because it can

detect a sudden rain and notify people in the house. Other possible applications are as smoke

sensors and high performance photoelectric switches.

ARE RAIN SENSORS NECESSARY?

In reality, the rain sensor is partly a safety product and in the automotive industry, safety

sells. I must admit that there are occasions when passing semi-trucks on the road in the right

weather conditions that a rain sensor would be a benefit.

Traditionally the rain sensor was available only on the high-priced luxury vehicles, but the

popularity is growing and it is becoming more mainstream and is appearing on several

average-priced cars. The list of manufacturers that are using a rain sensor on 2002 models

includes BMW, Ford, General Motors, Jaguar, Lexus, Mercedes Benz, Peugeot and

Volkswagen. Each is designed on the same basic principles.

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