114326649-automatic-gear-shifting-mechanism-for-two-wheeler.docx 456dz

AUTOMATIC GEAR SHIFTING MECHANISM FOR TWO WHEELER

A PROJECT REPORT

Submitted by In partial fulfillment for the award of the degree

Of IN MECHANICAL ENGINEERING

ANNA UNIVERSITY: CHENNAI 600 025 NOV/DEC 2012

ANNA UNIVERSITY: CHENNAI 600 025

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BONAFIDE CERTIFICATE

Certified that this project report “AUTOMATIC GEAR SHIFTING MECHANISM FOR TWO WHEELER”Is the bonafide work of “] ” Whocarried out the project work under my supervision.

SIGNATURE

SIGNATURE

]

Submitted for the project viva-voce held at Tagore Institute of Engineering and Technology on ……………..

…………………………

………………………..

Internal Examiner

External Examiner

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ACKNOWLEDGEMENT Weexpressour

sincere

thanks

to

our

beloved

philanthropic

MANAGEMENTofTagore institute of Engineering and Technology trust for having provided with necessary resources to complete this project. We extend our extreme gratitude alwaysto our

beloved visionary Principal

and thank him for his motivation and moral towards us to complete this project. We express our deep sense of gratitude and profound thanks to Head of Mechanical Engineering Department,for her remarkable guidance which was an inspiration to us. We have immense pleasure to express our hearty thanks to our beloved Project Co-, Assistant Professor of Mechanical Engineering Department, for her unflinching throughout our project . We have privileged to thank our beloved supervisor .,Assistant Professor of Mechanical Engineering Department, for her enlightening thoughts and meticulous guidance that helped us in doing our project. We also express our gratefulness to our parents, faculty and friends for their affectionate blessings and loving cooperation at all stages of this academic venture.

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ABSTRACT This project titled as “Automatic Gear Shifting Mechanism for Two wheelers”. This is a fabrication and implementation project. The project provides solution for gear shifting for the Bikes. The enger bikes that now ply on the road have transmission of manual type of gear changing. The manual type of transmission is preferred for the perfect performance without a loss in power but a compromise for comfortless. In this type manual system of power transmission there is easiness of gear shifting but there is a definite loss of power and mileage. The main objective of this project is to create a mechanism to reduce the inconvenience caused when changing gears in the bikes. The gear shifting is achieved by a simple modification to the gear box. This is a versatile pack, simple and can be fitted to any bikes. Moreover the whole set up is small and requires a very small space. This can sure be a standard fitment if proper marketing strategy is carried out. The main purpose of this project is used to automate the gear changing mechanism in vehicles. In this project we are doing the gear changing mechanism using with the help of sensors & actuators. This is very useful for the gear changing mechanism in automobile vehicles.

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CHAPTER-I

INTRODUCTION The paper deals with the real time project, “Automatic Gear Shifting Mechanism for Two wheelers” which was done in the academic year 2012- 2013. This project is aimed at giving driver the convenience for gear shifting& better performance. The bike with this project will have a stepper motor, microcontroller &sensors.

The clutch operation may or may not be put in the bike depending on the . The power for gear shifting is got from stepper motor. The power for stepper motor is from the battery. So a bike with a battery fitment can be easily adaptable to this project. The project has been started as a concept and it requires a lot more work to be done to put in a bike.

PROBLEM DEFINITION: Whenever a project is carried out there is a reason behind it. The existing cars now pose some problems for the drivers. In the Manual Transmission cars the main problem for the drivers is the gear shifting. But the engineering concept behind this type of transmission paves way for higher power transmission efficiency. More over the mileage of the car and life is also more. These cars do not give much of comfort ness for the drivers in the of using the gear lever and the clutch. Also it occupies a major area in the cabin resulting in the space congestion. These are the problems in the Manual Transmission cars.

In the Automatic Transmission type of cars, the gear shifting is easy. We just have to select the drive band, which is already preset. This selection may be either of lever type or a set of buttons. This is easy for the drivers as they don’t have to use clutch during gear shift. But there is a compromise for power transmission and mileage. As the gear selection is by a fluid, power is required to drive it, so the engine performance is reduced. So the problem here is mileage drop, power loss and also it is costly.

The need of the hour, combining the position of both MT and AT a mechanism has to be created for better mileage and comfortable gear shifting. This is the objective of the project. So a car with this project provides ease of gear shift as in AT without a compromise 5

in mileage as in MT. the cost of the project is less as it requires a minor alteration in the gear box. TRANSMISSION Gearbox" redirects here. For the video game developer, see Gearbox Software.

Five-speed + reverse gearbox from the 1600 Volkswagen Golf (2009). A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a live axle.[1] Often transmission refers simply to the gearbox that uses gears and gear trains to providespeed and torque conversions from a rotating power source to another device.[2][3] In British English, the term transmission refers to the whole drive train, including clutch, gearbox, prop shaft (for rear-wheel drive), differential, and final drive shafts. In American English, however, the distinction is made that a gearbox is any device which converts speed and torque, whereas a transmission is a type of gearbox that can be “shifted” to dynamically change the speed-torque ratio such as in a vehicle. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and anywhere else where rotational speed and torque needs to be adapted. Often, a transmission will have multiple gear ratios (or simply “gears”), with the ability to switch between them as speed varies. This switching may be done manually (by the operator), or automatically. Directional (forward and reverse) control may also be provided. 6

Single-ratio transmissions also exist, which simply change the speed and torque (and sometimes direction) of motor output. In motor vehicles, the transmission will generally be connected to the crankshaft of the engine. The output of the transmission is transmitted via driveshaft to one or more differentials, which in turn, drive the wheels. While a differential may also provide gear reduction, its primary purpose is to permit the wheels at either end of an axle to rotate at different speeds (essential to avoid wheel slippage on turns) as it changes the direction of rotation. Conventional gear/belt transmissions are not the only mechanism for speed/torque adaptation. Alternative

mechanisms

include torque

converters and

power

transformation

(for

example, diesel-electric transmission and hydraulic drive system). Hybrid configurations also exist.

EXPLANATION Early transmissions included the right-angle drives and other gearing in windmills, horsepowered devices, and steam engines, in of pumping, milling, and hoisting. Most modern gearboxes are used to increase torque while reducing the speed of a prime mover output shaft (e.g. a motor crankshaft). This means that the output shaft of a gearbox will rotate at a slower rate than the input shaft, and this reduction in speed will produce a mechanical advantage, causing an increase in torque. A gearbox can be set up to do the opposite and provide an increase in shaft speed with a reduction of torque. Some of the simplest gearboxes merely change the physical direction in which power is transmitted. Many typical automobile transmissions include the ability to select one of several different gear ratios. In this case, most of the gear ratios (often simply called "gears") are used to slow down the output speed of the engine and increase torque. However, the highest gears may be "overdrive" types that increase the output speed.

Manual Manual transmission come in two basic types: 

a simple but rugged sliding-mesh or unsynchronized / non-synchronous system, where straight-cut spur gear sets are spinning freely, and must be synchronized by the operator matching engine revs to road speed, to avoid noisy and damaging "gear clash",



and the now common constant-mesh gearboxes which can include non-synchronised, or synchronized / synchromesh systems, where typically diagonal cut helical (or 7

sometimes either straight-cut, or double-helical) gear sets are constantly "meshed" together, and a dog clutch is used for changing gears. On synchromesh boxes, friction cones or "synchro-rings" are used in addition to the dog clutch to closely match the rotational speeds of the two sides of the (declutched) transmission before making a full mechanical engagement. The former type was standard in many vintage cars (alongside e.g. epicyclic and multi-clutch systems) before the development of constant-mesh manuals and hydraulic-epicyclic automatics, older heavy-duty trucks, and can still be found in use in some agricultural equipment. The latter is the modern standard for on- and off-road transport manual and semiautomatic transmission, although it may be found in many forms; e.g., non-synchronised straight-cut in racetrack or super-heavy-duty applications, non-synchro helical in the majority of heavy trucks and motorcycles and in certain classic cars (e.g. the Fiat 500), and partly or fully synchronised helical in almost all modern manual-shift enger cars and light trucks. Manual transmissions are the most common type outside North America and Australia. They are cheaper, lighter, usually give better performance, and fuel efficiency (although automatic transmissions with torque converter lockup and advanced electronic controls can provide similar results). It is customary for new drivers to learn, and be tested, on a car with a manual gear change. In Malaysia and Denmark all cars used for testing (and because of that, virtually all those used for instruction as well) have a manual transmission. In Japan, the Philippines, ,Poland, Italy, Israel,

the Netherlands, Belgium, New

Zealand, Austria, Bulgaria, the UK,[6][7] Ireland,[7] Sweden, Norway, Estonia, , Spain, Switzerland, the Australian states of Victoria,[8]Western Australia and Queensland, Finland, Lithuania and the Czech Republic, a test using an automatic car does not entitle the driver to use a manual car on the public road; a test with a manual car is required.[citation much

more

common

than

automatic

needed]

Manual transmissions are

transmissions

in Asia, Africa, South

America and Europe. Manual transmissions can include both synchronized and unsynchronized gearing. For example, reverse gear is usually unsynchronised, as the drive is only expected to engage it when the vehicle is at a standstill. Many older (up to 1970s) cars also lacked syncro on first gear (for various reasons - cost, typically "shorter" overall gearing, engines typically having more low-end torque, the extreme wear which would be placed on a frequently used 1st gear synchroniser...), meaning it also could only be used for moving away from a stop unless the

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driver became adept at double-declutching and had a particular need to regularly downshift into the lowest gear. Some manual transmissions have an extremely low ratio for first gear, which is referred to as a "creeper gear" or "granny gear". Such gears are usually not synchronized. This feature is common on pickup trucks tailored to trailer-towing, farming, or construction-site work. During normal on-road use, the truck is usually driven without using the creeper gear at all, and second gear is used from a standing start. Some off-road vehicles, most particularly the Willys Jeep and its descendents, also had transmissions with "granny first"s either as standard or an option, but this function is now more often provided for by a low-range transfer gearbox attached to a normal fully synchronised transmission.

Non-synchronous There are commercial applications engineered with designs taking into that the gear shifting will be done by an experienced operator. They are a manual transmission, but are known as non-synchronized transmissions. Dependent on country of operation, many local, regional, and national laws govern the operation of these types of vehicles (see Commercial Driver's License). This class may include commercial, military, agricultural, or engineering vehicles. Some of these may use combinations of types for multi-purpose functions. An example would be a power take-off(PTO) gear. The non-synchronous transmission type requires an understanding of gear range, torque, engine power, and multi-functional clutch and shifter functions. Also see Double-clutching, and Clutch-brake sections of the main article.

Automatic Most modern North American and Australian and some European and Japanese cars have an automatic transmission that will select an appropriate gear ratio without any operator intervention. They primarily use hydraulics to select gears, depending on pressure exerted by fluid within the transmission assembly. Rather than using a clutch to engage the transmission, a fluid flywheel, or torque converter is placed in between the engine and transmission. It is possible for the driver to control the number of gears in use or select reverse, though precise control of which gear is in use may or may not be possible. Automatic transmissions are easy to use. However, in the past, automatic transmissions of this type have had a number of problems; they were complex and expensive, sometimes had reliability problems (which sometimes caused more expenses in repair), have often been less fuel-efficient than their manual counterparts (due to "slippage" in the torque converter), and

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their shift time was slower than a manual making them uncompetitive for racing. With the advancement of modern automatic transmissions this has changed.[citation needed] Attempts to improve the fuel efficiency of automatic transmissions include the use of torque converters which lock up beyond a certain speed, or in the higher gear ratios, eliminating power loss, and overdrive gears which automatically actuate above certain speeds; in older transmissions both technologies could sometimes become intrusive, when conditions are such that they repeatedly cut in and out as speed and such load factors as grade or wind vary slightly. Current computerized transmissions possess very complex programming to both maximize fuel efficiency and eliminate any intrusiveness. This is due mainly to electronic advances rather than mechanical ones although improvements in CVT technology and the use of automatic clutches have also helped. The 2012 model of the Honda Jazz sold in the UK actually claims marginally better fuel consumption for the CVT version than the manual version. For certain applications, the slippage inherent in automatic transmissions can be advantageous; for instance, in drag racing, the automatic transmission allows the car to be stopped with the engine at a high rpm (the "stall speed") to allow for a very quick launch when the brakes are released; in fact, a common modification is to increase the stall speed of the transmission. This is even more advantageous for turbocharged engines, where the turbocharger needs to be kept spinning at high rpm by a large flow of exhaust in order to keep the boost pressure up and eliminate the turbo lag that occurs when the engine is idling and the throttle is suddenly opened.

Semi-automatic A hybrid form of transmission where the an integrated control system handles manipulation of the clutch automatically, but the driver can still - and may be required to - take manual control of gear selection. This is sometimes called a "clutchless manual," or "automated manual" transmission. Many of these transmissions allow the driver to fully delegate gear shifting choice to the control system, which then effectively acts as if it was a regular automatic transmission. They are generally designed using manual transmission "internals", and when used in enger cars, have synchromesh operated helical constant mesh gear sets. Early semi-automatic systems used a variety of mechanical and hydraulic systems - including centrifugal clutches, torque converters, electro-mechanical (and even electrostatic) and servo/solenoid controlled clutches - and control schemes - automatic declutching when moving the gearstick, pre-selector controls, centrifugal clutches with drum-sequential shift

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requiring the driver to lift the throttle for a successful shift, etc. - and some were little more than regular lock-up torque converter automatics with manual gear selection. Most modern implementations, however, tend to be standard or slightly modified manual transmissions (and very occasionally modified automatics, even including a few cases of CVTs with "fake" fixed gear ratios), with servo-controlled clutching and shifting under command of the central engine computer. These are intended to be a combined replacement option both for more expensive and less efficient "normal" automatic systems, and for drivers who prefer manual shift but are no longer able to operate a clutch, and s are encouraged to leave the shift lever in fully automatic "Drive" most of the time, only engaging manualsequential mode for sporty driving or when otherwise strictly necessary. Specific types of this transmission include: Easytronic, Tiptronic and Geartronic, as well as the systems used as standard in all ICE-powered Smart-MCC vehicles, and on geared stepthrough scooters such as the Honda Super Cub or Suzuki Address. A dual-clutch transmission uses two sets of internals which are alternately used, each with its own clutch, so that a "gearchange" actually only consists of one clutch engaging as the other disengages, making for a supposedly "seamless" shift with no break in (or jarring reuptake of) power transmission. Each clutch's attached shaft carries half of the total input gear complement (with a shared output shaft), including synchronised dog clutch systems that preselect which of its set of ratios is most likely to be needed at the next shift, under command of a computerised control system. Specific types of this transmission include: Direct-Shift Gearbox. There are also sequential transmissions which use the rotation of a drum to switch gears, much like those of a typical fully manual motorcycle.[9] These can be designed with a manual or automatic clutch system, and may be found both in automobiles (particularly track and rally racing cars), motorcycles (typically light "step-thru" type city utility bikes, e.g. the Honda Super Cub) and quadbikes (often with a separately engaged reversing gear), the latter two normally using a scooter-style centrifugal clutch.

MOTOR CYCLE TRANSMISSION A motorcycle transmission is a transmission created specifically for motorcycle applications. They may also be found in use on other light vehicles such as motor tricycles and quadbikes, offroad buggies, mowers and other utility vehicles, microcars, and even some superlight sports cars.

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CLUTCH The clutch in a manual-shift motorcycle transmission is typically an arrangement of plates stacked in alternating fashion, one geared on the inside to the engine and the next geared on the outside to the transmission input shaft. Whether wet (rotating in engine oil) or dry, the plates are squeezed together by a spring, causing friction build up between the plates until they rotate as a single unit, driving the transmission directly. A lever on the handlebar exploits mechanical advantage through a cable or hydraulic arrangement to release the clutch spring, allowing the engine to freewheel with respect to the transmission. Automatic and semi-automatics typically use a centrifugal clutch which operates in a different fashion. At idle, the engine is disconnected from the gearbox input shaft, allowing both it and the bike to freewheel (unlike torque converter automatics, there is no "idle creep" with a properly adjusted centrifugal clutch). As the throttle is opened and engine speed rises, counterweights attached to movable inner friction surfaces (connected to the engine shaft) within the clutch assembly are thrown gradually further outwards, until they start to make with the inside of the outer housing (connected to the gearbox shaft) and transmit an increasing amount of engine power. The effective "bite point" is found automatically by equilibrium where the power being transmitted through the (still-slipping) clutch is equal to what the engine can provide. This allows relatively fast full-throttle takeoffs (with the clutch adjusted so the engine will be turning near its maximum-torque rpm) without the engine slowing or bogging down, as well as more relaxed starts and low-speed manoeuvres at lower throttle settings and rpms. Above a certain engine speed - once the bike is properly in motion, so the gearbox input shaft is also rotating quickly and so allowing the engine to accelerate further by way of clutch slip the outward pressure of the weighted friction plates is sufficient that the clutch will enter full lock-up, the same as a conventional plate-clutch with a fully released lever or pedal. After this, there is no clutch slip, and the engine is locked to and providing all of its available power to the transmission; engine rpm is now dependent on the road speed and the current gear ratio (under either control in a semi-auto, or reliant on road speed (and sometimes load/throttle position) in a CVT setup). In a typical CVT, the gear ratio will be chosen so the engine can reach and maintain its maximum-power speed as soon as possible (or at least, when at full throttle, in a partially load-dependent system), but in a semi-auto the rider is responsible for this choice, and they can ride around all day in top gear (or first) if they so prefer. Also, once the engine is turning fast enough to lock the clutch, it will stay fully engaged until the RPMs fall below that critical point again, even if the throttle is fully 12

released. Below the lock-up point, partially or fully releasing the throttle can lead to the RPM falling off rapidly, thanks to the loop of lower engine speed meaning less friction pressure. This toggle-like mode of operation can lead to certain characteristic centrifugalclutch-automatic behaviour, such as being able to freewheel rapidly downhill from a standstill, with engine braking only being triggered by turning the throttle briefly (and not then cancellable without braking to quite a slow, gear-dependent pace), and lockup triggering at a lower speed with full versus minimal throttle.

CONSRUCTION Pre-unit construction, also called separate construction, is a motorcycle engine architecture where the engine and gearbox are separate casings. In unit construction the engine and gearbox share a single housing. In many modern designs, the engine sits in front of the gearbox. From a sprocket on one side of the crankshaft, a chain will drive the clutch, which can often be found behind a large circular cover on one side of the gearbox. The clutch is connected to the gearbox input shaft. For motorcycles with chain drive, the gearbox output shaft is typically connected to the sprocket which drives the final drive chain. Most manual motorcycle gearboxes have "constant mesh" gears which are always mated but may rotate freely on a shaft until locked by a toothed sliding collar or "dog clutch". Since the gears are always rotating and can only be accessed sequentially, synchromesh is not generally needed. To save space, both shafts may contain a mixture of fixed and free-spinning gears, with some gears built into the sliding parts.

Comparison to other automated transmissions The automatic transmission is fully automatic and one does not need to change gears at all, which happens at the discretion of the computer in the car whereas in the semi-automatic transmission one can up-shift or down-shift without pressing the clutch. The gear can be engaged in manual mode wherein one can move it up and down to change the gears or one could operate the paddle shifters, just behind the steering wheel to perform the same operation. Many modern automated transmissions can also operate in the same manner as a conventional type of automatic transmission by allowing the transmission's computer to automatically change gear if, for example, the driver were redlining the engine. The ability to shift gears manually, often via paddle shifters, can also be found on certain automatic transmissions (manumatics such as Tiptronic) and continuous variable transmissions (CVTs) (such as Lineartronic). 13

Despite superficial similarity to other automated transmissions, automated transmissions differ significantly in internal operation and driver's "feel" from manumatics and CVTs. A manumatic, like a standard automatic transmission, uses a torque converter instead of clutch to manage the link between the transmission and the engine, while a CVT uses a belt instead of a fixed number of gears. A semi-automatic transmission offers a more direct connection between the engine and wheels than a manumatic and is preferred in high performance driving applications, while a manumatic is often preferred for street use because its fluid coupling makes it easier for the transmission to consistently perform smooth shifts,[1] and CVTs are generally found in gasoline-electric hybrid engine applications. Typically semi-automatic transmissions are more expensive than manumatics and CVTs, for instance BMW's 7-speed Double Clutch Transmission is a $3900 CAD the standard 6-speed manual, while the 6-speed Steptronic Automatic was only a $1600 CAD option.[2] In a given market, very few models have two choices of automated transmission; for instance the BMW 645Ci/650i (E63/64) (standard 6-speed manual) had an optional 6-speed automatic "Steptronic" or 7-speed Getrag SMG III single-clutch semi-automatic transmission until after the 2008 model year, when the SMG III was dropped.[3] Many sport luxury manufacturers such as BMW offer the manumatic for their mainstream lineup (such as the BMW 328i and BMW 535i) and the semi-automatic for their high-performance models (the BMW M3 and BMW M5).[2] The automated transmission may be derived from a conventional automatic; for instance Mercedes-Benz's AMG Speedshift MCT automated transmission is based on the 7GTronic manumatic, however the latter's torque converter has been replaced with a wet, multiplate launch clutch.[4] Other automated transmissions have their roots in a conventional manual; the SMG II drivelogic (found in the BMW M3 (E46) is a Getrag 6-speed manual transmission, but with an electrohydraulically actuated clutch pedal, similar to an Formula One style transmission.[5][6][7] The most common type of semi-automatic transmission in recent years has been the dual clutch type, since single-clutch types such as the SMG III have been criticized for their general lack of smoothness in everyday driving (although being responsive at the track)

OPERATION In

standard mass-production automobiles, the gear lever appears similar to manual shifts,

except that the gear stick only moves forward and backward to shift into higher and lower gears, instead of the traditional H-pattern. The Bugatti Veyron uses this approach for its seven-speed transmission. InFormula One, the system is adapted to fit onto the steering 14

wheel in the form of two paddles; depressing the right paddle shifts into a higher gear, while depressing the left paddle shifts into a lower one. Numerous road cars have inherited the same mechanism. Hall effect sensors sense the direction of requested shift, and this input, together with a sensor in the gear box which senses the current speed and gear selected, feeds into a central processing unit. This unit then determines the optimal timing and torque required for a smooth clutch engagement, based on input from these two sensors as well as other factors, such

as

engine

rotation,

the Electronic

Stability

Control, air

conditioner and dashboardinstruments. The central processing unit powers a hydro-mechanical unit to either engage or disengage the clutch, which is kept in close synchronization with the gear-shifting action the driver has started. In some cases, the hydro-mechanical unit contains a servomotor coupled to a gear arrangement for a linearactuator, which uses brake fluid from the braking system to impel a hydraulic cylinder to move the main clutch actuator. In other cases, the clutch actuator may be completely electric. The power of the system lies in the fact that electronic equipment can react much faster and more precisely than a human, and takes advantage of the precision of electronic signals to allow a complete clutch operation without the intervention of the driver. For the needs of parking, reversing and neutralizing the transmission, the driver must engage both paddles at once; after this has been accomplished, the car will prompt for one of the three options. The clutch is really only needed to start the car. For a quicker upshift, the engine power can be cut, and the collar disengaged until the engine drops to the correct speed for the next gear. For the teeth of the collar to slide into the teeth of the rings, both the speed and position must match. This needs sensors to measure not only the speed, but the positions of the teeth, and the throttle may need to be opened softer or harder. The even-faster shifting techniques like powershifting require a heavier gearbox or clutch or even a dual clutch transmission.

ELECTROHYDURALIC MANUAL TRANSMMISION Electrohydraulic manual transmission is a type of semi-automatic transmission system, which uses an automated clutch unlike conventional manual transmissions where the driver operates the clutch. The clutch is controlled by electronic computers and hydraulics. To change gears, the driver selects the desired gear with the transmission shift lever, and the system automatically operates the clutch and throttle to match revs and engage the clutch again. 15

Also, many such transmissions operate in sequential mode where the driver can only upshift or downshift by one gear at a time. Depending on the implementation, some computer-controlled electrohydraulic manual transmissions will automatically shift gears at the right points (like an automatic transmission), while others require the driver to manually select the gear even when the engine is at the redline. Despite superficial similarity, clutchless manual transmission differ significantly in internal operation and driver's 'feel' from manumatics, the latter of which is an automatic transmission (automatics use a torque converter instead of clutch to manage the link between the engine and the transmission) with ability to signal shifts manually.

DESIGN OF PROJECT: The project is done as a table top on the FIAT car’s gear box. The project design comprises of deg the following parts, 1. Hydraulic circuit 2. Electronic circuit 3. Mechanical components

HYDRAULIC CIRCUIT: Hydraulic motion is selected for gear shifting owing to its large load acceptance and ease of adaptability in the car. Also the gear shift should be quick. The basic components design is explained in detail. CYLINDER DESIGN: Load required to move the selector rod or to change the gear F=30 Kg Pressure built in the compressor unit

P=10 bar

To find: Cylinder dimensions D,L=? 1. Cylinder diameter D=? P=F/A 5 2 (10*10 )*(/4)*D = 30*9.81 D=0.0194 m = 20 mm 2. Cylinder length L =? Cylinder length L= Stroke Length+ Piston thickness+ Clearance 16

L= 30+10+7 = 47 mm L=47mm Cylinder diameter= 20mm

Cylinder length= 47mm

SELECTION OF PUMP: Selection of pump is based on following characteristics: 1. Select the actuator that is appropriate based on loads encountered. 2. Determine the flow rate requirements. This involves the calculation of the flow rate necessary to drive the actuator to move the load through a specified distance within the given time. 3. Determine the pump speed and select the prime mover. This, together with the flow rate calculation, determines the pump size 4. Select the pump based on application 5. Select the system pressure. These involves in with the actuator size and magnitude of the resistive force produced by the external load on the system. Also involved here is the total amount of power to be delivered by the pump. 6. Select the reservoir and associated plumping, including piping, valving, hydraulic cylinders, motors and other miscellaneous components. 7. Calculate the overall cost of the system. 8. Consider factors such as noise levels, horse power loss, need for a heat exchanger due to heat generated, pump wear, scheduled maintenance service to provide a desired life of the total system. The above characteristics are satisfied by the GEAR OIL PUMP and the following data are obtained from measurement, Do =75 mm Di =50 mm W= 25 mm N=1440 rpm 1. Flow rate Q= (/4)*(Do2-Di2)*W*N = (/4)*(0.0752-0.0502)*0.050*1440 = 0.0883 m3/S = 0.00147 m3/min = 1.47 Ltrs/min 2. Power required = Pressure*Flow rate= (10*105)*0.0883 = 88.3 kw 17

SELECTION OF RESERVIOR: 1. Reservoir Capacity= 2.5 to 3 Times of Pump flow = 3*1.47 = 4.41 Ltrs =4 Ltrs 2. Size of the copper tube =6 mm(for transmitting hydraulic fluid to valves)

HYDRAULIC CIRCUIT DIAGRAM: /

11

8

5

9 7

/

10

6

2

1 1 Hydraulic circuit diagram of the project

18

3

4

1. Reservoir.

7. Cylinder piston assembly

2. Pump.

8. Limit Switch

3. Clutch

9. Gear Box

4. Engine

10. Gear selector rod

5. Inlet Solenoid Valve

11. Spring

6. Outlet Solenoid Valve

ELECTRONIC CIRCUIT: The electronic circuit is used for governing the hydraulic operation. For this purpose we have used two solenoid valves (inlet and outlet) for each gear to be shifted. The supply voltage is from battery which is 12V. there will be six buttons 1, 2, 3, 4, R, N for gear shifting. Each actuates the gear corresponding when pressed. The diagram below shows the electronic circuit for various operation of the gear shifter. i. Engaging first gear B1

C 12 V VVV V

Sole1

ii. Maintaining gear position LS2

C 12 V VVV V

Sole1

iii. Releasing gear-neutral position 19

BN

12 V VVV V

Sole2

iv. Gear changing

Sole1

C

12 V VVV V

Sole2

MECHANICAL COMPONENTS: The main mechanical component for the project is the spring. The spring is used to counter balance the force exerted by the piston. Moreover it is useful in the return motion of the gear selector rod during gear disengagement. Presence of spring on the gear selector rod helps in the quick action that is required during the gear shift.

DESIGN OF SPRINGS:

We have formula for deflection

Y = 8PD3n/Gd4 20

Where, Y=deflection of spring=1.5 Cm P=load acting on the spring=30 Kg D=Diameter of spring=3.5 Cm d= Diameter of spring coil=0.4 Cm G=modulus of elasticity of spring material=2*105 N/mm2 N=no of coils in the spring=?

No of coils in the spring, n=YGd4/8PD3 = 1.5*2*105*0.44*100/(8*30*9.81*3.53) = 8 coils

WORKING PRINCIPLE: The main driving force for the gear shifting is by the hydraulic fluid. The gear shifting along with the clutch operation works with the pressing of buttons. On pressing the button corresponding to the gear, three operations take place, 1. Engine rotation 2. Clutch engagement 3. Pump rotation

When the car is switched on the engine rotates, on pressing the button clutch engages. Now electromagnetic clutch engages the pump. Due to the pump rotation the hydraulic fluid is pumped from reservoir to the inlet solenoid valve. Through this valve the fluid pushes the piston in the cylinder. This motion causes the gear shifter rod to engage the gear which is fitted to the piston. In order to avoid slippage of gear a limit switch is used to sense the position of selector rod and cut off the supply. To bring the car to neutral position we press the N button. Now the outlet solenoid valve energizes so the fluid in the cylinder rushes back to the sump with the aid of spring tension. If the next higher gear has to be selected, the same operation takes place on pressing the next button. 21

CURRENT STATUS:

Presently we have done this project as a table top working model. This consists of various parts which are listed below.

1) FIAT Gearbox 2) TOYOTA Power steering compressor 3) Motor for driving the compressor 4) Electro magnetic clutch 5) Tank or reservoir for storing the hydraulic fluid 6) Valves for controlling the flow of hydraulic fluid 7) Limit switch to cut off the supply 8) Hydraulic cylinder and piston assembly 9) Copper tubes for transportation of fluid 10)Fluid Hoses 11)Base structure for holding the gearbox and motor arrangement

The current model is a simple one which is actuated by a stick switch governing the gear selection. This set up works good for two gears. In the future there are plans to incorporate the clutch action in the set up by using the electronic clutch.

WORKING PRINCIPLE  A method of controlling a gear change of an automobile, said automobile comprising an internal combustion engine.  An automatic transmission connected to an output rotation shaft of said engine so as to transmit the rotational output of said engine to drive wheels of said automobile through any selected one of a plurality of gear ratios.  A load device selectively connectable to said output rotation shaft of said engine via selectively-connecting means for generating a gear change control signal for selecting one of said gear ratios of said 22

automatic transmission in accordance with one of operational conditions of said automobile and said engine said method comprising the steps of controlling said selectively-connecting means when said gear change signal-generating means generates the control signal for shifting up the gear in said automatic transmission, in such a manner that said selectively-connecting means connects said load device to said output rotation shaft of said engine.  Battery is giving the microcontroller unit. The proximity sensor is used to detect the wheel speed and this signal is given to the microcontroller unit. The 1st gear is done by manually press the button and the succeeding gears all are down automatically by the microcontroller unit.  The two electro-magnetic coils are fixed to the gear shaft of the two ends. One is used to shift the gear in upward direction. Another one is used to shift the gear in downward direction. These two coil is operated depends upon the speed of the vehicle this is automatically done with the help of microcontroller unit c programming language.

fig. 1.1 MICRO-CONTROLLER BASED AUTOMATIC ELECTRO-MAGNETIC GEAR SHIFTING SYSTEM

LIST OF MATERIALS Sl. No.

PARTS

Qty.

Material

i.

Frame Stand

1

Mild Steel

ii.

Battery

1

Lead Acid

iii.

Electro magnetic coil

2

Coil

23

iv.

Bearing with Bearing Cap

1

M.S

v.

Engine

1

75 Cc

vi

Chain with Sprocket

1

M.S

1 meter

Plastic

viii.

Connecting Tube

ix.

Bolt and Nut

-

M.S

x

Wheel Arrangement

1

-

Xi

Microcontroller Unit

1

Electronics

ELECTRO MAGNETIC COIL

fig.1.2 ELECTRO MAGNETIC COIL

The key to understanding the role of permanent magnet’s gear shifting lies in the general issue of biasing. Consider the simplest magnetic as shown in the figure, but omit the lower electromagnet. By omitting the finite permeability of the iron, the current in the coil controls the flux density.

fig.1.3 Proximity_Sensors 24

MICROCONTROLLER UNIT In our project Atmega 16 Is the microcontroller unit.

Features • High-performance, Low-power AVR® 8-bit Microcontroller • Advanced RISC Architecture – 131 Powerful Instructions – Most Single-clock Cycle Execution – 32 x 8 General Purpose Working s – Fully Static Operation – Up to 16 MIPS Throughput at 16 MHz – On-chip 2-cycle Multiplier • Nonvolatile Program and Data Memories – 16K Bytes of In-System Self-Programmable Flash Endurance: 10,000 Write/Erase Cycles – Optional Boot Code Section with Independent Lock Bits In-System Programming by On-chip Boot Program True Read-While-Write Operation – 512 Bytes EEPROM Endurance: 100,000 Write/Erase Cycles – 1K Byte Internal SRAM – Programming Lock for Software Security • JTAG (IEEE std. 1149.1 Compliant) Interface – Boundary-scan Capabilities According to the JTAG Standard – Extensive On-chip Debug – Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG Interface • Peripheral Features – Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes – One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture Mode – Real Time Counter with Separate Oscillator – Four PWM Channels – 8-channel, 10-bit ADC 8 Single-ended Channels 7 Differential Channels in TQFP Package Only 25

2 Differential Channels with Programmable Gain at 1x, 10x, or 200x – Byte-oriented Two-wire Serial Interface – Programmable Serial USART – Master/Slave SPI Serial Interface – Programmable Watchdog Timer with Separate On-chip Oscillator – On-chip Analog Comparator • Special Microcontroller Features – Power-on Reset and Programmable Brown-out Detection – Internal Calibrated RC Oscillator – External and Internal Interrupt Sources – Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby and Extended Standby • I/O and Packages – 32 Programmable I/O Lines – 40-pin PDIP, 44-lead TQFP, and 44-pad MLF • Operating Voltages – 2.7 - 5.5V for ATmega16L – 4.5 - 5.5V for ATmega16 • Speed Grades – 0 - 8 MHz for ATmega16L – 0 - 16 MHz for ATmega16

SPECIFICATION OF FOUR STROKE PETROL ENGINE: Type

:

Four strokes

Cooling System

:

Air Cooled

Bore/Stroke

:

50 x 50 mm

Piston Displacement

:

98.2 cc

Compression Ratio

:

6.6: 1

26

Maximum Torque

:

0.98 kg-m at 5,500RPM

fig.1.4 FOUR STROKES PETROL ENGINE

ADVANTAGES

 It requires simple maintenance cares  The safety system for automobile.  Checking and cleaning are easy, because of the main parts are screwed.  Easy to Handle.  Low cost automation Project  Repairing is easy.  Replacement of parts is easy. APPLICATIONS

 It is very much useful for Car Owners & Auto-garages. 

Thus it can be useful for the two wheeler application.

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CONCLUSION This project work has provided us an excellent opportunity and experience, to use our limited knowledge. We gained a lot of practical knowledge regarding, planning, purchasing, assembling and machining while doing this project work. We feel that the project work is a good solution to bridge the gates between institution and industries.

We are proud that we have completed the work with the limited time successfully. The AUTOMATIC ELECTRO-MAGNETIC GEAR SHIFTING SYSTEM is working with satisfactory conditions.

We are able to understand the difficulties in maintaining the

tolerances and also quality. We have done to our ability and skill making maximum use of available facilities.

In conclusion remarks of our project work, let us add a few more lines about our impression project work. Thus we have developed a “AUTOMATIC ELECTROMAGNETIC GEAR SHIFTING SYSTEM” which helps to know how to achieve low cost automation. The application of electro-magnetic coil produces smooth operation. By using more techniques, they can be modified and developed according to the applications.

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