ABSTRACT

The basic aim of steering is to ensure that the wheels are pointing in the desired

directions. This is typically achieved by a series of linkages, rods, pivots and

gears. One of the fundamental concepts is that of caster angle – each wheel is

steered with a pivot point ahead of the wheel; this makes the steering tend to be

self-centring towards the direction of travel. When the driver turns the steering

wheel, a shaft from the steering column turns a steering gear. The steering gear

moves tie rods that connect to the front wheels. The tie rods move the front wheels

to turn the vehicle right or left. The steering system must provide control over the

direction of travel of the vehicle; good maneuverability for parking the vehicle;

smooth recovery from turns, as the driver releases the steering wheel; and

minimum transmission of road shocks from the road surface. The steering system

provides control over direction of travel, good manoeuvrability, smooth recovery

from turns, and minimum transmission of road shocks.

1. INTRODUCTION

The most conventional steering arrangement is to turn the front wheels using a

hand–operated steering wheel which is positioned in front of the driver, via

the steering column, which may contain universal joints (which may also be part

of the collapsible steering column design), to allow it to deviate somewhat from a

straight line. Other arrangements are sometimes found on different types of

vehicles, for example, a tiller or rear–wheel steering. Tracked vehicles such

as bulldozers and tanks usually employ differential steering — that is, the tracks

are made to move at different speeds or even in opposite directions,

using clutches and brakes, to bring about a change of course or direction.

The direction of motion of a motor vehicle is controlled by a steering system.

A basic steering system has 3 main parts: A steering box connected to the steering

wheel. The linkage connecting the steering box to the wheel assemblies at the

front wheels. And front suspension parts to let the wheel assemblies pivot.

When the driver turns the steering wheel, a shaft from the steering column turns a

steering gear. The steering gear moves tie rods that connect to the front wheels.

The tie rods move the front wheels to turn the vehicle right or left.

Steering is the collection of components, linkages, etc. which allow

a vessel (ship, boat) or vehicle (car, motorcycle, bicycle) to follow the desired

course. An exception is the case of rail transport by which rail tracks combined

together with railroad switches (and also known as 'points' in British English)

provide the steering function. The primary purpose of the steering system is to

allow the driver to guide the vehicle.

Figure-1.1 Steering gear

There are 2 basic types of steering boxes - those with rack-and-pinion gearing, and

those with worm gearing. In both cases, the gearing in the steering box makes it

easier for the driver to turn the steering wheel, and hence, the wheels.

A rack-and-pinion steering system has a steering wheel, a main-shaft, universal

joints, and an intermediate shaft. When the steering is turned, movement is

transferred by the shafts to the pinion. The pinion is meshed with the teeth of the

rack, so pinion rotation moves the rack from side to side. This type of steering is

used on passenger vehicles because it is light, and direct.

This steering system has worm gearing. It provides a gear reduction, and a 90

degree change in direction. It has more parts and joints than the rack type, but it is

more robust, and may be used on heavier vehicles.

To allow heavy transport vehicles to carry extra weight, two steering axles may be

used. They’re connected by a link to a common steering box. These vehicles are

called tandem, or twin-steered vehicles.

Some passenger vehicles also steer the rear wheels slightly. This gives improved

manoeuvrability. The system is known as 4-wheel steering.

It can be controlled mechanically, through a direct connection, between the front

and rear steering boxes.

Or it can be computer-controlled.

With heavier vehicles, increased use of front-wheel-drive, and wider, low-profile

tyres, more steering effort is needed, so power steering is used.

An engine-driven hydraulic pump provides pressure that helps the driver steer the

vehicle. The power steering system is designed so that the vehicle can still be

controlled, even if the engine or the power steering system, fails.

2. WHEELED VEHICLE STEERING

2.1 Basic geometry

The basic aim of steering is to ensure that the wheels are pointing in the desired

directions. This is typically achieved by a series of linkages, rods, pivots and

gears. One of the fundamental concepts is that of caster angle – each wheel is

steered with a pivot point ahead of the wheel; this makes the steering tend to be

self-centring towards the direction of travel.

The steering linkages connecting the steering box and the wheels usually conform

to a variation of Ackermann steering geometry, to account for the fact that in a

turn, the inner wheel is actually travelling a path of smaller radius than the outer

wheel, so that the degree of toe suitable for driving in a straight path is not suitable

for turns. The angle the wheels make with the vertical plane also influences

steering dynamics (camber angle) as do the tires.

Many modern cars use rack and pinion steering mechanisms, where the steering

wheel turns the pinion gear; the pinion moves the rack, which is a linear gear that

meshes with the pinion, converting circular motion into linear motion along the

transverse axis of the car (side to side motion). This motion applies

steering torque to the swivel pin ball joints that replaced previously

used kingpins of the stub axle of the steered wheels via tie rods and a

short lever arm called the steering arm.

The rack and pinion design has the advantages of a large degree of feedback and

direct steering "feel". A disadvantage is that it is not adjustable, so that when it

does wear and develop lash, the only cure is replacement.

BMW began to use rack and pinion steering systems in the 1930s, and many other

European manufacturers adopted the technology. American automakers adopted

rack and pinion steering beginning with the 1974 Ford Pinto.[1]

Figure 2.1.1 Ackermann Steering mechanism

Older designs use two main principles: the worm and sector design and the screw

and nut. Both types were enhanced by reducing the friction; for screw and nut it is

the recirculating ball mechanism, which is still found on trucks and utility

vehicles. The steering column turns a large screw which meshes with nut by

recirculating balls. The nut moves a sector of a gear, causing it to rotate about its

axis as the screw is turned; an arm attached to the axis of the sector moves

the Pitman arm, which is connected to the steering linkage and thus steers the

wheels. The recirculating ball version of this apparatus reduces the considerable

friction by placing large ball bearings between the screw and the nut; at either end

of the apparatus the balls exit from between the two pieces into a channel internal

to the box which connects them with the other end of the apparatus, thus they are

"recirculated".

The recirculating ball mechanism has the advantage of a much greater mechanical

advantage, so that it was found on larger, heavier vehicles while the rack and

pinion was originally limited to smaller and lighter ones; due to the almost

universal adoption of power steering, however, this is no longer an important

advantage, leading to the increasing use of rack and pinion on newer cars. The

recirculating ball design also has a perceptible lash, or "dead spot" on center,

where a minute turn of the steering wheel in either direction does not move the

steering apparatus; this is easily adjustable via a screw on the end of the steering

box to account for wear, but it cannot be entirely eliminated because it will create

excessive internal forces at other positions and the mechanism will wear very

rapidly. This design is still in use in trucks and other large vehicles, where rapidity

of steering and direct feel are less important than robustness, maintainability, and

mechanical advantage.

The worm and sector was an older design, used for example in Willys and

Chrysler vehicles, and the Ford Falcon (1960's). To reduce friction, the sector is

replaced by a roller or rotating pins on the rocker shaft arm.

Other systems for steering exist, but are uncommon on road vehicles. Children's

toys and go-karts often use a very direct linkage in the form of a bell crank (also

commonly known as a Pitman arm) attached directly between the steering column

and the steering arms, and the use of cable-operated steering linkages (e.g.

the capstan and bowstring mechanism) is also found on some home-built vehicles

such as soapbox cars and recumbent tricycles.

Figure 2.1.2 Ackermann steering geometry

2.2 Power Steering

Power steering helps the driver of a vehicle to steer by directing some of the its

power to assist in swiveling the steered road wheels about their steering axes. As

vehicles have become heavier and switched to front wheel drive, particularly using

negative offset geometry, along with increases in tire width and diameter, the

effort needed to turn the wheels about their steering axis has increased, often to the

point where major physical exertion would be needed were it not for power

assistance. To alleviate this auto makers have developed power steering systems,

or more correctly power-assisted steering, since on road-going vehicles there has

to be a mechanical linkage as a fail-safe. There are two types of power steering

systems: hydraulic and electric/electronic. A hydraulic-electric hybrid system is

also possible.

A hydraulic power steering (HPS) uses hydraulic pressure supplied by an engine-

driven pump to assist the motion of turning the steering wheel. Electric power

steering (EPS) is more efficient than hydraulic power steering, since the electric

power steering motor only needs to provide assistance when the steering wheel is

turned, whereas the hydraulic pump must run constantly. In EPS, the amount of

assistance is easily tunable to the vehicle type, road speed, and even driver

preference. An added benefit is the elimination of environmental hazard posed by

leakage and disposal of hydraulic power steering fluid. In addition, electrical

assistance is not lost when the engine fails or stalls, whereas hydraulic assistance

stops working if the engine stops, making the steering doubly heavy as the driver

must now turn not only the very heavy steering—without any help—but also the

power-assistance system itself.

Figure 2.2.2 Power steering

2.3 Speed Sensitive Steering

An outgrowth of power steering is speed sensitive steering, where the steering is

heavily assisted at low speed and lightly assisted at high speed. Auto makers

perceive that motorists might need to make large steering inputs while

manoeuvring for parking, but not while traveling at high speed. The first vehicle

with this feature was the Citroën SM with its Diravi layout, although rather than

altering the amount of assistance as in modern power steering systems, it altered

the pressure on a centring cam which made the steering wheel try to "spring" back

to the straight-ahead position. Modern speed-sensitive power steering systems

reduce the mechanical or electrical assistance as the vehicle speed increases,

giving a more direct feel. This feature is gradually becoming more common.

2.4 Four Wheel Steering

In an active four-wheel steering system, all four wheels turn at the same time when

the driver steers. In most active four-wheel steering systems, the rear wheels are

steered by a computer and actuators. The rear wheels generally cannot turn as far

as the front wheels. There can be controls to switch off the rear steer and options

to steer only the rear wheels independently of the front wheels. At low speed (e.g.

parking) the rear wheels turn opposite of the front wheels, reducing the turning

radius by up to twenty-five percent, sometimes critical for large trucks or tractors

and vehicles with trailers, while at higher speeds both front and rear wheels turn

alike (electronically controlled), so that the vehicle may change position with

less yaw, enhancing straight-line stability. The "snaking effect" experienced

during motorway drives while towing a travel trailer is thus largely nullified.[dubious  –  discuss]

Four-wheel steering found its most widespread use in monster trucks, where

manoeuvrability in small arenas is critical, and it is also popular in

large farm vehicles and trucks. Some of the modern European Intercity buses also

utilize four-wheel steering to assist manoeuvrability in bus terminals, and also to

improve road stability. The first rally vehicle to use the technology was the

Peugeot 405 Turbo 16. Its debut was at the 1988 Pikes Peak International Hill

Climb, where it set a record breaking time of 10:47.77. [3] The car would go on to

victory in the 1989 and 1990 Paris-Dakar Rally, again driven by Ari Virtanen.

Previously, Honda had four-wheel steering as an option in their 1987–

2001 Prelude and Honda Ascot Innova models (1992–1996). Mazdaalso offered

four-wheel steering on the 626 and MX6 in 1988. General

Motors offered Delphi's Quadrasteer in their consumer

Silverado/Sierra and Suburban/Yukon. However, only 16,500 vehicles were sold

with this system from its introduction in 2002 through 2004. Due to this low

demand, GM discontinued the technology at the end of the 2005 model year.[4] Nissan/Infiniti offer several versions of their HICAS system as standard or as an

option in much of their line-up. A new "Active Drive" system is introduced on the

2008 version of the Renault line. It was designed as one of several measures to

increase security and stability. The Active Drive should lower the effects of under

steer and decrease the chances of spinning by diverting part of the G-forces

generated in a turn from the front to the rear tires. At low speeds the turning circle

can be tightened so parking and maneuvering is easier.

Figure 2.4.1 Four wheel steering

3. PRINCIPLE OF STEERING

The steering system must provide control over the direction of travel of the

vehicle; good maneuverability for parking the vehicle; smooth recovery from

turns, as the driver releases the steering wheel; and minimum transmission of road

shocks from the road surface. The steering system provides control over direction

of travel, good manoeuvrability, smooth recovery from turns, and minimum

transmission of road shocks.

Figure 3.1 Steering digram

The effort by the driver is transferred from the steering wheel, down the steering

column, to a steering box.

The steering box converts the rotary motion of the steering wheel, to the linear

motion needed to steer the vehicle. It also gives the driver a mechanical advantage.

The linear motion from the steering box is then transferred by tie-rods, to the

steering arms at the front wheels. The tie rods have ball joints that allow steering

movement, and movement of the suspension.

The steering-arm ball-joints are arranged so that movement in the suspension does

not affect steering operation.

4 TYPES OF STEERING SYSTEM

4.1. Rack & Pinion Steering System

Many modern cars use rack and pinion steering mechanisms, where the steering

wheel turns the pinion gear; the pinion moves the rack, which is a linear gear that

meshes with the pinion, converting circular motion into linear motion along the

transverse axis of the car (side to side motion). This motion applies

steering torque to the swivel pin ball joints that replaced previously

used kingpins of the stub axle of the steered wheels via tie rods and a

short lever arm called the steering arm.

The rack and pinion design has the advantages of a large degree of feedback and

direct steering "feel". A disadvantage is that it is not adjustable, so that when it

does wear and develop lash, the only cure is replacement.

Figure 4.2.1 Components of rack and pinion steering system

The primary components of the rack and pinion steering system are:

1. Rubber Bellows

2. Pinion

3. Rack

4. Inner Ball Joint

5. Tie Rod

Rubber Bellows:- This rubber bellows is attached to the Rack and Pinion

housing. It protects the inner joints from dirt and contaminants. In addition, it

retains the grease lubricant inside the rack and pinion housing. There is an

identical bellows on the other end of the rack for the opposite side connection.

Figure 4.2.2 Steering Gear

Pinion:- The pinion is connected to the steering column. As the driver turns the

steering wheel, the forces are transferred to the pinion and it then causes the rack

to move in either direction. This is achieved by having the pinion in constant mesh

with the rack.

Figure 4.2.3 Clashing gears

Rack:- The rack slides in the housing and is moved by the action of the meshed

pinion into the teeth of the rack. It normally has an adjustable bush opposite the

pinion to control their meshing, and a nylon bush at the other end.

Figure 4.2.4 Gear

Inner Ball Joint Or Socket:- The inner ball joint is attached to the tie-rod, to

allow for suspension movement and slight changes in steering angles.

Figure 4.2.4 Steering rod viewed

Tie Rod:- A tie rod end is attached to the tie-rod shaft. These pivot as the rack is

extended or retracted when the vehicle is negotiating turns. Some tie-rods and tie-

rod ends are left or right hand threaded. This allows toe-in or toe-out to be

adjusted to the manufacturer's specifications.

Figure 4.2.5 Tie rod

4.2. Recirculating Ball type

Recirculating ball, also known as recirculating ball and nut or worm and

sector, is a steering mechanism commonly found in older automobiles, and

some trucks. Most newer cars use the more economical rack and pinion steering

instead, but some manufacturers (including Chrysler and General Motors) still use

this technology in some models; e.g., the Jeep Wrangler and the Crossfire for the

durability and strength inherent in the design.

Figure 4.2.1 Recirculating ball

Mechanism:-

The recirculating ball steering mechanism contains a worm gear inside a block

with a threaded hole in it; this block has gear teeth cut into the outside to engage

the sector shaft (also called a sector gear) which moves the Pitman arm. The

steering wheel connects to a shaft, which rotates the worm gear inside of the

block. Instead of twisting further into the block, the worm gear is fixed so that

when it spins, it moves the block, which transmits the motion through the gear to

the pitman arm, causing the roadwheels to turn.

The primary components of the recirculating ball and nut steering system

are:

1. Pitman Arm Shaft

2. Idler Arm

3. Track Rod Or Centre Link

4. Tie Rod

5. Tie Rod End

6. Adsutment Sleeve

Pitman Arm Shaft:- The pitman arm shaft is attached to the steering box by a

spline and nut. As the driver turns the steering wheel, the steering box mechanism

moves the steering linkages via the pitman arm shaft either left or right, depending

on the direction in which the steering wheel is turned.

The steering box provides the change of angle at 90° to the steering linkage.

Idler Arm:- The idler arm is attached to the chassis and is positioned parallel to

the pitman arm.

Figure 4.2.3 Idler arm

Track Rod or Centre Link:- The track rod connects the pitman arm shaft to the

idler arm shaft. In this way any movement in the pitman arm shaft is directly

applied to the idler arm shaft.

Figure 4.2.4 Tracker rod

Tie Rod:- The tie rods connect the track rod to the steering arms that are located

on the steering knuckles. Thus all movement from the pitman arm shaft is relayed

directly to the front wheels, which steer the vehicle.

Figure 4.2.5 Tracker rod

Tie Rod End:- Tie rod ends are attached to the tie-rod shaft. These pivot as the

rack is extended or retracted when the vehicle is negotiating turns. Tie-rods and

tie-rod ends are left or right hand threaded.

Figure 4.2.6 Tie rod end

Adjustment Sleeve:- The adjustment sleeve connects the tie-rod to the tie-rod end.

It provides the adjustment point for toe-in or toe-out, depending on the

manufacturers' specifications.

Figure 4.2.7 Adjustment sleeve

4.3. Four Wheel Steering System

Some cars have four-wheel steering.

This can be computer controlled or it can be mechanical, through a direct

connection between the front and rear steering boxes, or it can be computer-

controlled, or the rear wheels can be mounted on special, compliant mounts. As

cornering forces are applied to them, they alter the steering angles.

Figure 4.3.1 Four wheel steering

With heavier vehicles, increased use of front-wheel drive, and wider, low-profile

tyres, more steering effort is needed, so power assistance is used.

A hydraulic pump is driven from the engine, to provide pressure to help the driver.

The power steering system is designed so that even if the engine or the power

steering system fails, the vehicle can still be controlled. However, much more

driver effort is required.

The relationships between the steering system, the wheel positions, and the

suspension system, form what is called the steering geometry. These relationships

must always stay within manufacturer specifications.

5. STEERING MECHANISMS

1. Ackermann steering geometry

2. Davis steering geometry

5.1. Ackermann steering geometry 

It is a geometric arrangement of linkages in the steering of a car or

other vehicle designed to solve the problem of wheels on the inside and outside of

a turn needing to trace out circles of different radius. It was invented by the

German Carriage Builder Georg Lankensperger in Munich in 1817, then patented

by his agent in England, Rudolph Ackermann (1764–1834) in 1818 for horse

drawn carriages. Erasmus Darwin may have a prior claim as the inventor dating

from 1758. A simple approximation to perfect Ackermann steering geometry may

be generated by moving the steering pivot points inward so as to lie on a line

drawn between the steering kingpins and the centre of the rear axle. The steering

pivot points are joined by a rigid bar called the tie rod which can also be part of

the steering mechanism, in the form of a rack and pinion for instance. With perfect

Ackermann, at any angle of steering, the centre point of all of the circles traced by

all wheels will lie at a common point. Note that this may be difficult to arrange in

practice with simple linkages, and designers are advised to draw or analyze their

steering systems over the full range of steering angles.

Figure 5.1.1 Ackermann steering

Modern cars do not use pure Ackermann steering, partly because it ignores

important dynamic and compliant effects, but the principle is sound for low speed

manoeuvres. Some race cars use reverse Ackermann geometry to compensate for

the large difference in slip angle between the inner and outer front tyres while

cornering at high speed. The use of such geometry helps reduce tyre temperatures

during high-speed cornering but compromises performance in low speed

maneuvers.

Figure 5.1.2 Rack pinion gear

The Ackerman Steering Principle defines the geometry that is applied to four

wheel drive to enable the correct turning

angle of the steering wheels to be generated when negotiating a corner or a

curve.An Ackermann steering gear has only

turning pairs and thus is preferred. Its drawback is that it fulfils the fundamental

equation of correct gearing at the middle and the two extreme position and not in

all positions.

With perfect Ackermann, at any angle of steering, the centre point of all of the

circles traced by all wheels will lie at a common point.

The intention of Ackermann geometry is to avoid the need for tyres to slip

sideways when following the path around a curve.The geometrical solution to this

is for all wheels to have their axles arranged as radii of a circle with a common

centre point. As the rear wheels are fixed, this centre point must be on a line

extended from the rear axle.

Intersecting the axes of the front wheels on this line as well requires that the inside

front wheel is turned, when steering, through a greater angle than the outside

wheel.The principle of Ackerman Steering is the relationship between the front

inside tire and front outside tire in a corner or curve.

5.2. Davis Steering Geometry

A Davis steering gear has sliding pairs which means more friction and easy

wearing. The gear fulfils the fundamental equation of gearing in all the positions.

However, due to easy wearing it becomes inaccurate after some time.

This is the reason why this type of steering mechaism are now absolute these days

and are not used in offroad vehicles as they are more prone to wear and tear.

Figure 5.2.1 Davis steering mechanism

It is recommended not to go for devis steering arrangement though it has accurate

mechanism and is mathematically better than ackerman

but it should noted that its availability is less and also it gets wear easily due to

sliding pair.

6. STEERING RATIO

Steering ratio refers to the ratio between the turn of the steering wheel (in

degrees) or handlebars and the turn of the wheels (in degrees).

The steering ratio, is the amount of degrees you have to turn the steering wheel,

for the wheels to turn an amount of degrees. In motorcycles and bicycles, the

steering ratio is always 1:1, because the steering wheel will always follow the

wheel. x:y means that you have turn the steering wheel x degree(s), for the

wheel(s) to turn y degree(s). In most passenger cars, the ratio is between 12:1 and

20:1. Example: If one complete turn of the steering wheel, 360 degrees, causes

the wheels to turn 24 degrees, the ratio is then 360:24 = 15:1 (360/24=15).

Figure 6.1.1 Steering Ratio Graph

A higher steering ratio means that you have to turn the steering wheel more, to get

the wheels turning, but it will be easier to turn the steering wheel. A lower steering

ratio means that you have to turn the steering wheel less, to get the wheels turning,

but it will be harder to turn the steering wheel. Larger and heavier vehicles will

often have a higher steering ratio, which will make the steering wheel easier to

turn. If a truck had a low steering ratio, it would be very hard to turn the steering

wheel. In normal and lighter cars, the wheels become easier to turn, so the steering

ratio doesn't have to be as high. In race cars the ratio becomes really low, because

you want the vehicle to respond a lot quicker than in normal cars. The steering

wheel will also become a lot harder to turn.

6.1. Variable Ratio Steering

A variable-ratio steering, is a system that uses different ratios on the rack, in a rack

and pinion steering system. At the center of the rack, the space between the teeth

are smaller and the space becomes larger as the pinion moves down the rack. In

the middle of the rack you'll have a higher ratio and the ratio becomes lower as

you turn the steering wheel towards lock. This makes the steering less sensitive,

when the steering wheel is close to its center position and makes it harder for the

driver to oversteer at high speeds. As you turn the steering wheel towards lock, the

wheels begins to react more to your steering input.

Figure 6.1.2 Steering effort characteristics

6.2. Turning circles

Figure 6.2.1 Turning circle

7. CONCLUSION

With the world’s highest growth rate for passenger vehicle production, the

Chinese automotive market crossed production volume of 3.8 million units in

2005. It is expected that China will surpass Japan and become the world’s second-

largest automotive market by 2010, trailing only the United States.

The Chinese automotive market is one of the most dynamic markets, not only for

its high growth rate, but also for the advanced technologies applied. For example,

one of the most advanced steering technologies, electric power steering (EPS), is

expected to emerge strongly and win a large market share during the next decade.

Pitman arm mechanisms have a steering 'box' where the shaft from the steering

wheel comes in and a lever arm comes out - the pitman arm. This pitman arm is

linked to the track rod or centre link, which is supported by idler arms. The tie

rods connect to the track rod. There are a large number of variations of the actual

mechanical linkage from direct-link where the pitman arm is connected directly to

the track rod, to compound linkages where it is connected to one end of the

steering system or the track rod via other rods. The example here shows a

compound link (left). Most of the steering box mechanisms that drive the pitman

arm have a 'dead spot' in the centre of the steering where you can turn the steering

wheel a slight amount before the front wheels start to turn. This slack can normally

be adjusted with a screw mechanism but it can't ever be eliminated. The traditional

advantage of these systems is that they give bigger mechanical advantage and thus

work well on heavier vehicles. With the advent of power steering, that has become

a moot point and the steering system design is now more to do with mechanical

design, price and weight. The following are the four basic types of steering box

used in pitman arm systems.

7. FUTURE SCOPE

You can expect to see several innovations that will improve fuel economy. One of

the coolest ideas on the drawing board is the "steer-by-wire" or "drive-by-wire"

system. These systems would completely eliminate the mechanical connection

between the steering wheel and the steering, replacing it with a purely electronic

control system. Essentially, the steering wheel would work like the one you can

buy for your home computer to play games. It would contain sensors that tell the

car what the driver is doing with the wheel, and have some motors in it to provide

the driver with feedback on what the car is doing. The output of these sensors

would be used to control a motorized steering system. This would free up space in

the engine compartment by eliminating the steering shaft. It would also reduce

vibration inside the car. General Motors has introduced a concept car, the Hy-wire,

that features this type of driving system. One of the most exciting things about the

drive-by-wire system in the GM Hy-wire is that you can fine-tune vehicle

handling without changing anything in the car's mechanical components -- all it

takes to adjust the steering is some new computer software. In future drive-by-wire

vehicles, you will most likely be able to configure the controls exactly to your

liking by pressing a few buttons, just like you might adjust the seat position in a

car today. It would also be possible in this sort of system to store distinct control

preferences for each driver in the family.

8. REFRENCES

1.  http://www.hemmings.com/hmn/stories/2010/07/01/hmn_feature20.html

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3.  "1988 Peugeot 405 T16 GR Pikes Peak". Retrieved 16 March 2015.

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Auto World. Retrieved 2010-06-11.

5.  https://www.audi-mediaservices.com/publish/ms/content/en/public/

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Sportiness, efficiency, premium comfort

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7.  Johnson, Erik (June 2007). "2008 Infiniti G37 Sport Coupe - Suspension,

Handling, and Four-Wheel Steering".

8.  http://www.porsche.com/usa/models/911/911-turbo/chassis/rear-axles-steering/

9.  http://www.porsche.com/usa/models/911/911-turbo-s/chassis/rear-axles-steering/

10.  http://www.carscoops.com/2014/10/new-renault-espace-comes-with-four.html

11.  http://www.autoevolution.com/news/2016-renault-megane-brings-four-wheel-

steering-87-inch-touchscreen-to-frankfurt-live-photos-99958.html

12.  http://en-voiture.blog.leparisien.fr/archive/2015/12/03/essai-renault-talisman-

amulette-16276.html

13.  "Toyota Camry Catalog".