RECENT TRENDS IN AUTOMOBILES by moses dhilip kumar

RECENT TRENDS IN AUTOMOBILES

ABSTRACT

          This paper presents the overview of recent developments in automobiles. The basic objective of this market research report “INDIAN AUTOMOBILE INDUSTRY-RECENT TRENDS” is to estimate the demand for automobiles from 2005-2012. The increased demand for Indian automobiles has resulted in a large number of multi-national auto companies, especially from Japan, USA and Europe, entering the Indian market and working in collaboration with the Indian firms. The report also examines the region wise demand and growth trends for the selected vehicles, and how they influence Indian’s GDP (Global Development Percentage) growth. Current technological trends in the automobile industry reflect many diverse disciplines. The trends which can examine the global automotive market are Global Market Dynamics, Establishment of Global Alliances, and Industry Consolidation. Alternate energy sources for cars, such as natural gas, electricity, ethanol and vegetable oil, began to view for consumer demand in the early 21^st century. Solar powered cars and hydrogen powered fuel cell cars remained in development stages. Hybrid automobiles combine an electric motor with batteries that are recharged by a small gas or diesel-powered engine. Ethanol is used as alternate fuel in the early 21^st century, it may increase in future. At the start of 21^st century, the trends of global trade and manufacturing flexibility continued. Computerization continued to be a major part of auto design and manufacture, as did the search for alternate fuels and more efficient automobile designs.

WHAT ARE THE BENEFITS OF USING ETHANOL?

Ethanol is a relatively low-cost alternative fuel, but what are the benefits of using ethanol or an ethanol blend in place of unblended gasoline?

Answer: Using ethanol as an alternative to gasoline provides several key benefits.

ETHANOL IS GOOD FOR THE ENVIRONMENT

Overall, ethanol is considered to be better for the environment than gasoline. Ethanol-fueled vehicles produce lower carbon monoxide and carbon dioxide emissions, and the same or lower levels of hydrocarbon and oxides of nitrogen emissions.

E85, a blend of 85 percent ethanol and 15 percent gasoline, also has fewer volatile components than gasoline, which means fewer emissions from evaporation.

Adding ethanol to gasoline in lower percentages, such as 10 percent ethanol and 90 percent gasoline (E10), reduces carbon monoxide emissions from the gasoline and improves fuel octane.

ETHANOL IS WIDELY AVAILABLE AND EASY TO USE

Flexible fuel vehicles that can use E85 are widely available and come in many different styles from most major auto manufacturers. E85 is also widely available at a growing number of stations throughout the United States. Flexible fuel vehicles have the advantage of being able to use E85, gasoline, or a combination of the two, giving drivers the flexibility to choose the fuel that is most readily available and best suited to their needs.

ETHANOL IS GOOD FOR THE ECONOMY

Ethanol production supports farmers and creates domestic jobs. And because ethanol is produced domestically, from domestically grown crops, it reduces U.S. dependence on foreign oil and increases the nation’s energy independence.

BLENDING ETHANOL WITH GASOLINE

E85, a blend of 85 percent ethanol and 15 percent gasoline, is used in flexible fuel vehicles, which are offered by most major auto manufacturers. Blends with more ethanol, such as E95, are also premium alternative fuels.

 Blends with lower concentrations of ethanol, such as E10 (10 percent ethanol and 90 percent gasoline), are sometimes used to increase octane and improve emissions quality, but are not considered alternative fuels.

TYPES OF ETHANOL

v E10 and other Low-Level Ethanol Blends

v E15-E20: Intermediate Ethanol Blends

v E85 Ethanol: Flex Fuel

E10 AND OTHER LOW-LEVEL ETHANOL BLENDS

Low-level ethanol blends are sold in every state. Gasoline now contains up to 10% ethanol (E10) to boost octane or meet air quality requirements.The Clean Air Act Amendment of 1990 (and subsequent laws) mandated the sale of oxygenated fuels in areas with unhealthy levels of carbon monoxide. This kicked off the modern U.S. ethanol industry growth.

Problems with groundwater contamination from the use of methyl tertiary butyl ether (MTBE)—the only other available oxygenate and principal octane booster—accelerated the use of ethanol in low-level blends.Auto manufacturers  approve the use of low-level blends because they work well in gasoline engines and create no noticeable difference in vehicle performance.

E15-E20: INTERMEDIATE ETHANOL BLENDS

Intermediate ethanol blends have an ethanol content greater than 10% and less than 85%. Fueling large numbers of vehicles with intermediate blends could provide similar benefits as fueling with low-level blends while increasing gasoline displacement and utilizing the nation's rapidly increasing ethanol production.

However, intermediate ethanol blends cannot yet be used legally in standard (non-flexible fuel) vehicles. Intermediate blends can be used today in flexible fuel vehicles but do not qualify as alternative fuels under the Energy Policy Act of 1992 (EPAct).

Some fueling stations currently use "blender pumps"—fuel dispensers that can create a variety of ethanol blends by mixing E10 with E85. The resulting intermediate blends can be used legally in flexible fuel vehicles but not in standard vehicles.

E85 ETHANOL                                                                                                       Drivers jumping on the latest gas-saving bandwagon may be in for a shock when they see fuel-economy estimates for the newest darlings of Detroit: E85 ethanol flex-fuel vehicles.

According to Environmental Protection Agency (EPA) estimation

·        Run a new V6 Chevrolet Impala on good-old gasoline( 21 miles per gallon in the city, 31 on the highway).

·        Burn E85 - a blend of 85 percent of the alcohol-based fuel ethanol (15  to 16 mpg city, 23 highway)

ALTERNATIVE FUEL VEHICLE

An E85 powered 2009 Chevrolet HHR.

Run a two wheel-drive V8 Ford F150 on regular unleaded gas, and the EPA says it'll get 14 mpg city, 19 mpg highway. Run it on E85 ethanol, and it gets 11 mpg city, 14 mpg highway. In other words, fill up on environmentally friendly E85 ethanol, and you'll get fewer miles per gallon than you would on gasoline.

E85 ethanol boosters are General Motors and Ford, which have mounted massive new E85 ethanol support programs. Spurred by public and private efforts to pump up E85 ethanol demand, ethanol producers themselves are pouring billions of dollars into building new refineries.

As with any alternative-fuel idea, however, the E85 ethanol story is one of tradeoffs. It pits, for example, E85 ethanol's ability to lower air pollution because it burns cleaner than gasoline against the potential environmental costs involved in ethanol production.

We've highlighted some tradeoffs in E85 ethanol fuel economy, but are there compromises in convenience and vehicle performance? These and other issues are thoroughly explored in the following sections:

E85 ETHANOL FLEX FUEL EXPLAINED

About one-third of all gasoline sold in the United States contains some ethanol, typically in a ratio of 90 percent gasoline and 10 percent ethanol. E85 gets its name from the way it inverts that formula, at 85 percent ethanol and 15 percent conventional gasoline.

We'll explain how ethanol is produced and why it's mixed with gasoline, and explore some of the controversy surrounding its place in environmental and public policy debates. Only a fraction of the cars and trucks on the road are "flex fuel" vehicles: those that can run on conventional gasoline or E85 ethanol fuel.

You'll learn why that number is growing, and how you can determine whether your next new car or truck -- or maybe the one you already own -- is an E85 ethanol flex-fuel vehicle.

EXPLANATION

Ethanol is an alcohol-based fuel made by fermenting and distilling starch crops, corn mostly. Only a relative handful of renewable energy companies produce it, but virtually all the ethanol they generate comes from renewable crops grown on American farms. On­e acre of corn can be processed into about 330 gallons of combustible ethanol.

Proponents argue that mixing 85 parts ethanol with 15 parts gasoline to create E85 ethanol fuel helps stretch the earth's supply of oil, which is finite. Supporters, such as the Renewable Fuels Association, say E85 ethanol fuel expands the market for U.S. crops and creates jobs in agriculture and refining.

By reducing oil imports, backers argue, ethanol eases the nation's trade imbalance and cuts down on the tax dollars and military resources needed to keep foreign oil flowing.

As for environmental benefits, the U.S. Department of Energy says vehicles fueled with E85 ethanol have lower carbon monoxide and carbon dioxide emissions than conventional gasoline or diesel vehicles. Ethanol is water soluble, non-toxic, and biodegradable. E85 ethanol contains far fewer potential contaminants than found in gasoline.

But for nearly every benefit ascribed to E85 ethanol, a detractor is ready with a counterpoint. For example, ethanol production requires burning non-renewable fossil fuels to plant, grow, and harvest the crops and operate refineries.

 A Cornell University agricultural expert says that, considering the energy costs of growing corn and converting it to ethanol, it takes far more energy to produce ethanol than it yields

National Ethanol Vehicle Coalition This cycle illustrates how plants, often corn, are turned into ethanol.

Of the roughly 250 million cars, trucks, SUVs, and minivans on America's roads, only about six million are capable of burning E85 ethanol. About half of these E85 ethanol flex-fuel vehicles are in commercial or government fleets.

The majority of private E85 vehicles come from Ford and General Motors, but certain Chrysler, Dodge, Jeep, Mercedes-Benz and Nissan models also are E85 ethanol-compatible. These vehicles have special components installed on the factory assembly line that monitor and compensate for the ethanol/gasoline mix. Their fuel systems are also fortified against the corrosive effects of E85 ethanol.

E85  THROUGHOUT  THE  YEARS

Henry Ford built an ethanol-burning Model T before World War I, and over the years, thousands of fleet vehicles were modified to run on ethanol-based blends. U.S. automakers began making E85 ethanol-compatible components standard on certain models in 1998.

Over the past year, Ford, GM, and DaimlerChrysler have seized the E85 ethanol mantle as a fuel-saving technology and a way to support the environment and promote domestic agriculture. These manufacturers say they plan to put a combined total of 2 million additional E85 ethanol flex-fuel vehicles on the road each year starting in 2007.

For 2007, 29 different models for sale in the U.S. are E85 ethanol flex-fuel capable. That's up from 20 for the 2006 model year. For 2007, GM has offered 17 E85 ethanol flex-fuel models totaling about 400,000 vehicles, compared to nine models in 2006. Ford expects to sell 250,000 E85 ethanol flex-fuel models in 2006.

Still, you'll need to look closely to identify one of these E85 ethanol flex-fuel vehicles. Some early E85 ethanol flex-fuel Fords carry a small road-and-leaf logo and decal reading "FFV," for Flexible Fuel Vehicle. GM identifies its E85 ethanol flex-fuel vehicles with yellow gas caps and "Flex Fuel E85" badges.

­The best ways to determine whether you have an E85 ethanol flex fuel vehicle is to consult your owner's manual or check for an identifying sticker inside the fuel door. A list of E85 ethanol flex fuel-compatible vehicles is also available from several Web sites, ­including fueleconomy.gov and e85fuel.com

HOW DOES E85 ETHANOL AFFECT YOU?

E85 ethanol flex-fuel vehicles have some special technology in them. We'll explain how that may affect their purchase and maintenance costs. The automakers say running a flex-fuel vehicle on E85 has no effect on performance. We'll share our real-world experiences to find out if that's true. And although the number of gas stations selling E85 ethanol fuel is growing, we'll explain why there are still so few of them, and why they are clustered in a few geographic areas. Finally, how does using E85 ethanol fuel affect your pocketbook? And should that be the determining factor in whether you decide to use it?

EXPLANATION

As the term "flexible fuel" implies, any E85 ethanol flex-fuel vehicle can run on 100 percent E85, 100 percent pump gasoline of any octane, or any combination of E85 ethanol and gasoline. The car's on-board diagnostic systems compensate for any of these blends to keep it running according to manufacturer's specifications.

Automakers spend an estimated $150 to make a vehicle E85-ethanol capable, but none charges customers more for an E85 ethanol flex-fuel vehicle compared to a gasoline-only counterpart. Neither do they vary horsepower ratings for E85 ethanol flex-fuel engines. E85 ethanol has an octane rating of 100-105, versus 85-95 for gasoline, but manufacturers do not tune E85 ethanol-capable engines for higher performance than their gas-only counterparts. This allows them to run efficiently on conventional gasoline.

On the road, real-world performance is indistinguishable. Consumer Guide's automotive editor’s road tested an E85 ethanol flex-fuel Impala on both 87 octane gasoline and E85 ethanol, and could not detect a difference in engine performance, smoothness, or sound.

Some E85 ethanol proponents say the blend keeps fuel systems cleaner than gasoline, for potentially lower long-term maintenance costs. Ford and GM have no special maintenance requirements for their E85 ethanol flex-fuel vehicles, but other manufacturers may require use of specific engine lubricants. Check your owner's manual or consult your dealer. Motorists fueling up with E85 ethanol should share that information with their dealer service department or parts supplier when ordering replacement parts.

WHERE  TO  FIND  E85

Efforts by automakers and the government to increase the number of gas stations that carry E85 ethanol have raised their ranks by some 100 stations over the past year. Nonetheless, only about 800 of the nation's 180,000 gas stations carry E85 ethanol fuel. Another 200 or so E85 ethanol refueling stations are fleet or government sites not open to the public. Most locations are in Midwest Corn Belt states, where E85 ethanol production and sales have for years benefited from government supports.

As of November 2006, according to the U.S. Department of Energy, Minnesota led the nation with 300 E85 ethanol fuel sites, followed by Illinois with 132, Missouri with 63, and Iowa with 56, and South Dakota with 50. Most states had fewer than a dozen. Alaska, Delaware, Hawaii, Maine, New Hampshire, New Jersey, Rhode Island, and Vermont had none. Go to E85refueling.com for a list of stations that carry E85.

Once you pull up to an E85 ethanol pump, you aren't likely to find the price per gallon of E85 significantly different from that of 87-octane regular grade gas. While some Midwest service stations price E85 ethanol as much as 30 cents per gallon below regular-grade gas, the EPA in November 2006 listed the average price for a gallon of E85 ethanol nationally at $2.41, compared to $2.23 per gallon for regular-grade gasoline.

Most E85 pumps are located in the Midwest, but they are popping up in almost all 50 states.

Supply, demand, and distribution costs figure among reasons E85 ethanol can be more expensive than conventional gasoline at the pump. Government and auto industry efforts to promote the fuel have increased demand for E85 ethanol, helping create a supply crunch at refineries. In addition, wholesale ethanol prices are increasing as oil companies stock up on the alcohol as a substitute for petroleum additives suspected of causing cancer. And E85 ethanol costs more to distribute than gas. The blend can't be pumped through petroleum pipelines because of the corrosive impact of its alcohol content,

For example, in the final analysis, of course, E85 producers and retailers are free to charge what they can to satisfy demand and make a profit. So you've found a station with E85 ethanol, decided the price was right, and you've filled the tank of your flex-fuel car or truck. How far will it take you?

Not as far as a tank of gasoline would. As the examples of the Impala and F 150 show, your fuel economy using E85 ethanol is lower than with gasoline. These are not isolated examples. Overall, depending on the vehicle, fuel economy with E85 ethanol is some 20 to 30 percent less than with gasoline. Consumer Guide's test Impala, for example, averaged 24.2 mpg on gasoline, but just 16.9 mpg in similar city/highway driving using E85 ethanol.

Looked at another way, a tank of E85 ethanol will take you only about 80 percent as far as you could drive on a tank of gasoline. On E85 ethanol, you'll stop more to refuel, have to plan ahead to make sure the station carries E85 ethanol, and perhaps pay more per gallon once you get there.

The difference in miles per gallon between gasoline and E85 ethanol has to do with E85 ethanol's lower energy content per unit of volume. Measured in British Thermal Units (BTUs), a gallon of E85 ethanol has only 72 percent of the energy in a gallon of gasoline. Go to fueleconomy.gov to compare EPA fuel-economy estimates for the same flex-fuel vehicle running on E85 ethanol and on gasoline.

So we've seen that choosing an E85 ethanol flex fuel vehicle and running it on E85 ethanol may not be to your personal advantage in terms of convenience and fuel cost. But it won't affect vehicle performance. And once you consider arguments on both sides of this the complex issue, you may decide that buying a flex-fuel vehicle and running it on E85 ethanol is a personal gesture of support for American agriculture, alternative fuels, and energy independence.

How Does Ethanol Performance Compare to Gasoline?

Ethanol is widely available and reasonably inexpensive, but what kind of performance can drivers expect from a car running on ethanol or an ethanol/gasoline blend?

Answer: One gallon of pure ethanol contains about 66 percent as much energy as a gallon of gasoline. A gallon of E85, a common blend of 85 percent ethanol and 15 percent gasoline, contains about 71 percent as much energy as a gallon of unblended gasoline.

Drivers who use E85 can expect about 15 percent less fuel economy than they would get with gasoline. Other performance factors such as power, acceleration, and cruising speed are essentially equivalent in vehicles burning E85 and conventional fuels.

HOW MUCH DOES IT COST TO USE ETHANOL?

Ethanol is a widely available alternative fuel that can be used in many vehicles that are already on the road, but is it cost-effective to use ethanol or an ethanol/gasoline blend in place of unblended gasoline?

Answer: A gallon of E85, a blend of 85 percent ethanol and 15 percent gasoline, usually costs about the same as a gallon of regular gasoline, although prices may vary somewhat depending on location.

COMPARABLE COST PER GALLON, BUT LESS FUEL ECONOMY

A gallon of ethanol contains less energy than a gallon of gasoline, however, so you may get lower mileage with ethanol and be required to fill your tank more often, which may could to your fuel costs.

For more current information about the cost of ethanol and other alternative fuels, download the most recent Alternative Fuel Price Report from the U.S. Department of Energy.

VEHICLES THAT USE ETHANOL COST NO MORE THAN OTHERS
Vehicles that can use E85 are widely available in many models—sedans, minivans, SUVs, pickups and light trucks and usually cost about the same as vehicles that run exclusively on gasoline. The U.S.  Department  of  Energy  provides  an  online Flexible Fuel Vehicle Cost Calculator that makes it easy to determine the costs and benefits of using E85 in a flexible fuel vehicle where you live.

MERITS

v A University of California study, by contrast, insists modern farm efficiency means ethanol generates more energy than it requires producing.

v Corn-based gasohol (a combination of unleaded gasoline and ethanol made from corn) reduces fossil energy use by 50 to 60 percent and pollution by 35 to 46 percent.

v  More than 11 percent of all automotive fuels sold in the United States were ethanol-blended in the early 21st century. That percentage may increase in the future.

DEMERITS

v Creating plant-based biofuels requires too much farmland to be practical or sustainable—land that would be better used to grow food.

v Producing ethanol and other biofuels takes more energy than the fuel can generate.

CONCLUSION

This paper concludes that the use of ethanol gives relatively a good fuel economy. Commercially speaking, tha cost of the ethanol is not so high as compared with the conventional gasoline. Moreover in the fast growing world, pollution is a main constraint. The use of ethanol fixs this constrain. Hence the usage of ethanol can be recommended in a wide range of automobiles.

AUTOMATIC HIGHWAY ANTI-COLLIDING SYSTEM

  

AUTOMATIC HIGHWAY

      ANTI-COLLIDING SYSTEM

moses dhilip kumar

                                           

                                   

SYNOPSIS:                 

·        Abstract

·        Introduction

·        Working principle

·        Construction details

Þ   Ultrasonic sensor

Þ   Relay

Þ   Non Inverting amplifier

Þ   DC motor

Þ   Solenoid

·        Working

·        Advantages

·        Conclusion

·        References

ABSTRACT:

                       We are living in an automobile society, and as far as this field is concerned the accidents are the main problems that have to be solved. In Chennai alone nearly 1900 fatal road accidents have taken place in 2005 which nearly claimed 1800 precious lives.

                                Driver’s assistance system plays a major role in cars since it minimizes the risk and consequences of accidents and increases the driving comfort level. Highway anti-colliding system is intended to provide drivers with brake assistance to avoid front end collision. On highways, if the principle other vehicle (POV) suddenly stops, then the host vehicle will collide it resulting in an accident. Due to less reaction time and loss of presence of mind, driver can’t stop the vehicle through brake.

              The aim of this paper is to stop the vehicle at such circumstances and this paper gives an outline of whole system and constructional features of each component and working principle. Adaptations of the system in the future automobiles have also been considered.

INTRODUCTION:

        

                              Most of the collisions take place between the rear of the principle other vehicle (POV) and the front of the host vehicle due to sudden stoppage of the POV and also this occurs when a vehicle is parked in the highways during night times which is not being recognized by the driver.  We are going to sense the stoppage of the POV (Principle other vehicle) using an ultrasonic sensor.  Any vehicle that reaches a critical distance (6-10m) towards the obstacle is necessary to be stopped and for this an actuating signal should be given to the relay and the solenoid. The sensor output voltage will actuate the brake shoes through solenoid and cuts the drive from the prime mover.

                                  This automotive collision avoidance has been developed in the centre for Automotive Research & Training, Department of Automobile engineering in MIT Campus, Anna University. The model on which the system is tested is made up of wooden chassis and a sheet metal body. A permanent magnet series motor is used to drive the vehicle. The current to the DC motor can be reversed to provide for a braking effort.

WORKING PRINCIPLE:

·        The principle of ultrasonic detection is based on measuring the time taken between transmission of an ultrasonic wave (pressure wave) and reception of its echo (return of transmitted wave). The distance range is 6-10 m.

·        The relay opens or closes its switch contacts in some prearranged and fixed combination. The contacts may be in the same circuit or a combination of circuit or in another circuit.

·        When a current is passed through the solenoid the slug is attracted towards the centre of the coil with a force determined by the current in the coil. The motion of the slug may be opposed by a spring to produce a displacement output, or the slug may simply free to move.

·        Torque is produced by interaction between the axial current carrying rotor conductors and the magnetic flux produced by the permanent magnets. The only way to control its speed is to vary the armature voltage with the help of an armature rheostat.

CONSTRUCTION DETAILS:

ULTRASONIC SENSORS:

Ultrasonic sensors have an acoustic transducer which is vibrating at ultrasonic frequencies. The pulses are emitted in a cone-shaped beam and aimed at a target object. Pulses reflected by the target to the sensor are detected as echoes.  The device measures the time delay between each emitted and echo pulse to accurately deter-mine the sensor-to-target distance.

    All materials sensing Ultrasonic Position Sensors solve the toughest sensing problems and detect targets made of virtually any material, regardless of color. They detect clear, transparent and shiny targets as easily as dark and opaque materials. This ability allows ultrasonic sensors to detect materials ranging from clear glass bottles to black rubber tires.  In a shrink wrapping operation, for instance, the sensor can accurately and repeatedly detect the wrapping material regard-less of how shiny or clear it may be. Ultrasonic sensors also work well in tough environments — fumes, dust, noisy.

Ultrasonic sensors are of the cylindrical type and they comprise of,

1. High voltage generator

2 .piezoelectric transducer (transmitter and receiver)

3 .signal processing stage

4. Output stage

Piezo  electric transducer

                                                              

Output stage

-20V

+20V

                

Signal processing stage

High voltage regulator

     

            Excited by the high voltage generator, the transducer (transmitter-receiver) generates a pulsed ultrasonic wave (200 to 500 kHz depending on the product) which travels through the ambient air at the speed of sound. When the wave strikes an object, it reflects (echo) and travels back towards the transducer. A micro controller analyses the signal received and measures the time interval between the transmitted signal and the echo. By comparison with the preset or learnt times, it determines and controls the output states.

     

The output stage controls a solid-state double switch (PNP and NPN transistor) corresponding to a NO contact (detection of object).

Input Voltage   : 10-30 V (DC).

Range               :  6-10 m.

Output Voltage: Analog, 0-10 V, 4-20 mA (PNP dual)

RELAY:

                     A relay is a device which functions as an electrically operated switch. In response to an electrical, known as control signal, the relay opens or closes its switch contacts in some prearranged and fixed combination. Dimension of the relay is about 95* 53*95 mm. The contacts may be in the same circuit or a combination of circuit or in another circuit. Supply voltage is about 15 volt.

         

NON INVERTING AMPLIFIER:

Vo = {1+ Rf/Ri}*Vi.

Rf and Ri is selected so as to give a gain of 1.4. We need the output voltage of 15 volt. The input voltage is 10 volts from the sensor. Rf and Ri is selected as 1.4 and 1 kilo ohms.

DC MOTOR:

                                 A permanent magnet dc (PMDC) motor is similar to an ordinary dc shunt motor except that its field is provided by permanent magnets instead of salient pole wound field structure. Ceramite ferrite magnets are used here. Low voltage PMDC motors produce less air noise and very little radio noise.

                     Torque is produced by interaction between the axial current carrying rotor conductors and the magnetic flux produced by the permanent magnets. The only way to control its speed is to vary the armature voltage with the help of an armature rheostat. Since magnets are permanent magnet, these are totally enclosed to prevent from magnetic junk.

SPECIFICATIONS OF PMDC MOTOR:

Torque	22 kg-m
Power	80 W
Speed	375 rpm
Voltage	24 V
Current	4.5 A

SOLENOID:

                            A solenoid consists of an electrical coil and a ferromagnetic slug which can move into or out of the coil. When a current is passed through the solenoid the slug is attracted towards the centre of the coil with a force determined by the current in the coil. The motion of the slug may be opposed by a spring to produce a displacement output, or the slug may simply free so that when the device is energized, it moves in one direction until it reaches an end to move.

               Most solenoids are linear devices, the electric current producing a linear displacement. They will give a continuous analog output or with a simple on/off input. The device is generally arranged when reenergized, a return spring forces it to the other end of its range of travel where it again reaches an end.

WORKING:

                  When the POV stops suddenly and if is within 6-10 m in front of our vehicle, the ultrasonic sensor will sense the reflected ultrasonic waves from the POV and generates an output voltage of 10 volts. This is given as input to a non inverting amplifier of R_f 1.5 kilo ohms and R_i 1 kilo ohms.  The output from the non inverting amplifier is 15 volts. This voltage is given as an input to a relay of 15 volts which is normally closed. The relay is normally closed with the DC motor circuit. Now the relay switch is opened thereby it cuts the DC motor drive. Due to inertial motion, the wheel tends to move in the forward direction. Using the same output voltage from the non inverting amplifier, the solenoid is actuated which presses the brake shoe against the wheel thereby stopping of the vehicle occur. Thus collision with the POV is avoided using our system. The following should also be incorporated with this system so as to avoid collision with our vehicle.

ADVANTAGES:

        

Ø Front End Collision is completely eliminated.

Ø The components used are easily available and construction is very simple; hence it a low cost technology.

Ø Practical implementation of the system is easy and necessary modifications are carried out for effective performance.

Ø Highly preferable at night hours during which most drivers feel fatigue.

LIMITATIONS:

                               While overtaking the forward vehicles, a certain distance should be maintained between the vehicles otherwise it leads to unnecessary braking of the vehicle. But this problem can be overcome by using a microcontroller in the system which analyses the signal and then only actuate the system.

CONCLUSION:

                               National Highway Traffic Safety Administration (NHTSA) estimates that most of the accidents involving forward end collision are due to the driver’s inattention or by vehicles following too closely and also it suggests a relatively simple technology needed for detection and prevention. Most of the accidents are forward collided. Thus by sensing the sudden stoppage of POV within the certain range in front of our vehicle, our brake system is actuated so as to avoid collision. The system can be further developed by using microcontrollers to analyze the signal. Thus this system is a safety system used in highways so as to avoid tail to head collision.

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