Suspension (Vehicle) - Wikipedia, The Free Encyclopedia

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The front suspension com ponents of aFord Model T.

The rear suspension on a truck: a leaf spring.

Suspen sion (vehicle)From Wikipedia, the free encyclopedia

Suspension is the term given to the system of springs, shock absorbers and li nkages that conne cts a vehicle to its wheels andallows relative m otion betw een the two. [1] Suspension systems

serve a dual pur pose contributing to the vehicle'sroadholding/handling a nd braking for g ood active safety anddriving pleasure, and keeping vehicle occupa nts comfortable andreasonably well i solated from ro ad noise, bumps, andvibrations,etc. T hese goals are general ly at odds, so the tuning of suspensions invo lves finding the right compromise. It is importantfor the suspensio n to keep th e road wheel in contact with theroad surface as much as possible, because all the r oad or groundforces acting on the vehicle d o so through the contact patches of the tires. The sus pension also protects the vehicle itself and a ny

cargo or luggage from damage and w ear. The design of front andrear suspen sion of a car may be different.

This article is primarily about four-wheeled (or more)vehicle suspension. For information on two-wheeled vehicles' suspensions see the motorcycle suspension,motorcycle fork, bicycle suspension, and bicycle fork artic les.

C ontents

1 History1.1 Horse drawn vehicles1.2 Automobiles

2 Important properties2.1 Spring rate

2.1. 1 Mat hematics of the spring rate2.2 Wheel rate2.3 Roll Rate2.4 Roll couple perce ntage2.5 Weight transfer

2.5.1 Unsprung weight transfer 2.5.2 Sprung weight transfer 2.5.3 Jacking forces

2.6 Travel2.7 Damping2.8 Camber control

2.9 Roll center height2.10 Instant center 2.11 Anti-dive and anti-squat2.12 Flexibility and vibration modes of the
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6/3/13 Suspension (vehicle) - Wikipedia, the free encyclopedia

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Part of car front suspension and steeringmechanism: tie rod, steering arm, king pin

axis (using ball joints).

Van Diemen RF01 Racing Car Suspension.

suspension elements2.13 Isolation from high frequency shock 2.14 Contribution to unsprung weight and totalweight2.15 Space occupied2.16 Force distribution2.17 Air resistance (drag)

2.18 Cost3 Springs and dampers

3.1 Passive suspensions3.1.1 Springs3.1.2 Dampers or shock absorbers

3.2 Semi-active and active suspensions3.3 Interconnected suspensions

4 Suspension geometry4.1 Dependent suspensions

4.2 Semi-independent suspension4.3 Independent suspension5 Tracked vehicles6 Armoured fighting vehicle suspension7 See also8 References9 External links

HistoryLeaf springs have been around since the early Egyptians.

Ancient military engineers used leaf springs in the form of bowsto power their siege engines, with little success at first. The use of leaf springs in catapults was later refined and made to work ears later. Springs were not only made of metal, a sturdy tree

branch could be used as a spring, such as with a bow.

Horse drawn vehicles

By the early 19th century, most British horse carriages were equippedwith springs; wooden springs in the case of light one-horse vehicles toavoid taxation, and steel springs in larger vehicles. These were madeof low-carbon steel and usually took the form of multiple layer leaf springs. [2]

The British steel springs were not well suited for use on America'srough roads of the time, and could even cause coaches to collapse if cornered too fast. In the 1820s, the Abbot Downing Company of Concord, New Hampshire re-discovered the antique system wherebythe bodies of stagecoaches were supported on leather straps called "thoroughbraces", which gave a swingingmotion instead of the jolting up and down of a spring suspension (the stagecoach itself was sometimes called a
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Strap suspension 1605

Henri Fournier on his uniquelydampened and racewinning 'MorsMachine', photo taken 1902

Citron BX Hydropneumaticsuspension - maximum to minimum

demonstration

"thoroughbrace").

Automobiles

Automobiles were initially developed as self-propelled versions of horse drawn vehicles. However, horse drawn vehicles had beendesigned for relatively slow speeds and their suspension was not well

suited to the higher speeds permitted by the internal combustionengine.

In 1901 Mors of Paris first fitted an automobile with shock absorbers.With the advantage of a dampened suspension system on his 'MorsMachine', Henri Fournier won the prestigious Paris-to-Berlin race onthe 20th of June 1901. Fournier's superior time was 11 hrs 46 min 10sec, while the best competitor was Lonce Girardot in a Panhard witha time of 12 hrs 15 min 40 sec. [3]

In 1920, Leyland Motors used torsion bars in a suspension system. In1922, independent front suspension was pioneered on the LanciaLambda and became more common in mass market cars from1932. [4]

Important properties

Spring rate

Further information: Spring rate

The spring rate (or suspension rate) is a component in setting thevehicle's ride height or its location in the suspension stroke. When aspring is compressed or stretched, the force it exerts is proportionalto its change in length. The spring rate or spring constant of a springis the change in the force it exerts, divided by the change in deflectionof the spring. Vehicles which carry heavy loads will often have heavier springs to compensate for the additional weight that would otherwisecollapse a vehicle to the bottom of its travel (stroke). Heavier springs

are also used in performance applications where the loadingconditions experienced are more extreme.

Springs that are too hard or too soft cause the suspension to become ineffective because they fail to properlyisolate the vehicle from the road. Vehicles that commonly experience suspension loads heavier than normal haveheavy or hard springs with a spring rate close to the upper limit for that vehicle's weight. This allows the vehicleto perform properly under a heavy load when control is limited by the inertia of the load. Riding in an emptytruck used for carrying loads can be uncomfortable for passengers because of its high spring rate relative to theweight of the vehicle. A race car would also be described as having heavy springs and would also beuncomfortably bumpy. However, even though we say they both have heavy springs, the actual spring rates for a

2,000 lb (910 kg) race car and a 10,000 lb (4,500 kg) truck are very different. A luxury car, taxi, or passenger bus would be described as having soft springs. Vehicles with worn out or damaged springs ride lower to theground which reduces the overall amount of compression available to the suspension and increases the amountof body lean. Performance vehicles can sometimes have spring rate requirements other than vehicle weight andload.
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Mathematics of the spring rate

Spring rate is a ratio used to measure how resistant a spring is to being compressed or expanded during thespring's deflection. The magnitude of the spring force increases as deflection increases according to Hooke'sLaw. Briefly, this can be stated as

where

F is the force the spring exertsk is the spring rate of the spring.

x is the deflection of the spring from its equilibrium position (i.e., when no force is applied on the spring)

Spring rate is confined to a narrow interval by the weight of the vehicle,load the vehicle will carry, and to a lesser extent by suspension geometry and performance desires.

Spring rates typically have units of N/mm (or lbf/in). An example of a linear spring rate is 500 lbf/in. For everyinch the spring is compressed, it exerts 500 lbf. A non-linear spring rate is one for which the relation betweenthe spring's compression and the force exerted cannot be fitted adequately to a linear model. For example, thefirst inch exerts 500 lbf force, the second inch exerts an additional 550 lbf (for a total of 1050 lbf), the third inchexerts another 600 lbf (for a total of 1650 lbf). In contrast a 500 lbf/in linear spring compressed to 3 inches willonly exert 1500 lbf.

The spring rate of a coil spring may be calculated by a simple algebraic equation or it may be measured in aspring testing machine. The spring constant k can be calculated as follows:

where d is the wire diameter, G is the spring's shear modulus (e.g., about 12,000,000 lbf/in or 80 GPa for steel), and N is the number of wraps and D is the diameter of the coil.

Wheel rate

Wheel rate is the effective spring rate when measured at the wheel. This is as opposed to simply measuring thespring rate alone.

Wheel rate is usually equal to or considerably less than the spring rate. Commonly, springs are mounted oncontrol arms, swing arms or some other pivoting suspension member. Consider the example above where thespring rate was calculated to be 500 lbs/inch, if you were to move the wheel 1 in (2.5 cm) (without moving thecar), the spring more than likely compresses a smaller amount. Lets assume the spring moved 0.75 in (19 mm),the lever arm ratio would be 0.75:1. The wheel rate is calculated by taking the square of the ratio (0.5625) timesthe spring rate, thus obtaining 281.25 lbs/inch. Squaring the ratio is because the ratio has two effects on thewheel rate. The ratio applies to both the force and distance traveled.

Wheel rate on independent suspension is fairly straightforward. However, special consideration must be taken

with some non-independent suspension designs. Take the case of the straight axle. When viewed from the frontor rear, the wheel rate can be measured by the means above. Yet because the wheels are not independent,when viewed from the side under acceleration or braking the pivot point is at infinity (because both wheels have
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moved) and the spring is directly inline with the wheel contact patch. The result is often that the effective wheelrate under cornering is different from what it is under acceleration and braking. This variation in wheel rate may

be minimized by locating the spring as close to the wheel as possible.

Wheel rates are usually summed and compared with the sprung mass of a vehicle to create a "ride rate" andcorresponding suspension natural frequency in ride (also referred to as "heave"). This can be useful in creating ametric for suspension stiffness and travel requirements for a vehicle.

Roll Rate

Roll rate is analogous to a vehicle's ride rate, but for actions that include lateral accelerations, causing a vehicle'ssprung mass to roll. It is expressed as torque per degree of roll of the vehicle sprung mass. It is influenced byfactors including but not limited to vehicle sprung mass, track width, CG height, spring and damper rates, anti-roll bar stiffness and tire pressure/construction. The roll rate of a vehicle can, and usually differs front to rear,which allows for the tuning ability of a vehicle for transient and steady state handling. The roll rate of a vehicledoes not change the total amount of weight transfer on the vehicle, but shifts the speed at which and percentageof weight transferred on a particular axle to another axle through the vehicle chassis. Generally, the higher the roll

rate on an axle of a vehicle, the faster and higher percentage the weight transfer on that axle.

Roll couple percentage

Roll couple percentage is a simplified method of describing lateral load transfer distribution front to rear, andsubsequently handling balance. It is the effective wheel rate, in roll, of each axle of the vehicle as a ratio of thevehicle's total roll rate. It is commonly adjusted through the use of anti-roll bars, but can also be changedthrough the use of different springs.

Weight transfer

Main article: Weight transfer

Weight transfer during cornering, acceleration or braking is usually calculated per individual wheel andcompared with the static weights for the same wheels.

The total amount of weight transfer is only affected by four factors: the distance between wheel centers(wheelbase in the case of braking, or track width in the case of cornering) the height of the center of gravity, themass of the vehicle, and the amount of acceleration experienced.

The speed at which weight transfer occurs as well as through which components it transfers is complex and isdetermined by many factors including but not limited to roll center height, spring and damper rates, anti-roll bar stiffness and the kinematic design of the suspension links. In most conventional applications, when weight istransferred though intentionally compliant elements such as springs, dampers and anti-roll bars, the weighttransfer is said to be "elastic", while the weight which is transferred through more rigid suspension links such asA-arms and toe links is said to be "geometric".

Unsprung weight transfer

Unsprung weight transfer is calculated based on the weight of the vehicle's components that are not supported by the springs. This includes tires, wheels, brakes, spindles, half the control arm's weight and other components.These components are then (for calculation purposes) assumed to be connected to a vehicle with zero sprung
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weight. They are then put through the same dynamic loads. The weight transfer for cornering in the front would be equal to the total unsprung front weight times the G-Force times the front unsprung center of gravity heightdivided by the front track width. The same is true for the rear.

Sprung weight transfer

Sprung weight transfer is the weight transferred by only the weight of the vehicle resting on the springs, not the

total vehicle weight. Calculating this requires knowing the vehicle's sprung weight (total weight less the unsprungweight), the front and rear roll center heights and the sprung center of gravity height (used to calculate the rollmoment arm length). Calculating the front and rear sprung weight transfer will also require knowing the rollcouple percentage.

The roll axis is the line through the front and rear roll centers that the vehicle rolls around during cornering. Thedistance from this axis to the sprung center of gravity height is the roll moment arm length. The total sprungweight transfer is equal to the G-force times the sprung weight times the roll moment arm length divided by theeffective track width. The front sprung weight transfer is calculated by multiplying the roll couple percentagetimes the total sprung weight transfer. The rear is the total minus the front transfer.

Jacking forces

Jacking forces are the sum of the vertical force components experienced by the suspension links. The resultantforce acts to lift the sprung mass if the roll center is above ground, or compress it if underground. Generally, thehigher the roll center, the more jacking force is experienced.

Travel

Travel is the measure of distance from the bottom of the suspension stroke (such as when the vehicle is on aack and the wheel hangs freely) to the top of the suspension stroke (such as when the vehicle's wheel can nolonger travel in an upward direction toward the vehicle). Bottoming or lifting a wheel can cause serious control

problems or directly cause damage. "Bottoming" can be caused by the suspension, tires, fenders, etc. runningout of space to move or the body or other components of the car hitting the road. The control problems caused

by lifting a wheel are less severe if the wheel lifts when the spring reaches its unloaded shape than they are if travel is limited by contact of suspension members (See Triumph TR3B.) Many off-road vehicles, such as desertracers, use straps called "limiting straps" to limit the suspensions downward travel to a point within safe limits for the linkages and shock absorbers. This is necessary, since these trucks are intended to travel over very roughterrain at high speeds, and even become airborne at times. Without something to limit the travel, the suspension

bushings would take all the force when the suspension reaches "full droop", and it can even cause the coilsprings to come out of their "buckets" if they are held in by compression forces only. A limiting strap is a simplestrap, often nylon of a predetermined length, that stops the downward movement at a preset point before thetheoretical maximum travel is reached. The opposite of this is the "bump-stop", which protects the suspensionand vehicle (as well as the occupants) from violent "bottoming" of the suspension, caused when an obstruction(or hard landing) causes the suspension to run out of upward travel without fully absorbing the energy of thestroke. Without bump-stops, a vehicle that "bottoms out" will experience a very hard shock when thesuspension contacts the bottom of the frame or body, which is transferred to the occupants and every connector and weld on the vehicle. Factory vehicles often come with plain rubber "nubs" to absorb the worst of the forces,and insulate the shock. A desert race vehicle, which must routinely absorb far higher impact forces, may be

provided with pneumatic or hydro-pneumatic bump-stops. These are essentially miniature shock absorbers(dampeners) that are fixed to the vehicle in a location such that the suspension will contact the end of the pistonwhen it nears the upward travel limit. These absorb the impact far more effectively than a solid rubber bump-
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stop will, essential because a rubber bump-stop is considered a "last-ditch" emergency insulator for theoccasional accidental bottoming of the suspension; it is entirely insufficient to absorb repeated and heavy

bottomings such as a high-speed off road vehicle encounters.

Damping

Damping is the control of motion or oscillation, as seen with the use of hydraulic gates and valves in a vehicles

shock absorber. This may also vary, intentionally or unintentionally. Like spring rate, the optimal damping for comfort may be less than for control.

Damping controls the travel speed and resistance of the vehicle's suspension. An undamped car will oscillate upand down. With proper damping levels, the car will settle back to a normal state in a minimal amount of time.Most damping in modern vehicles can be controlled by increasing or decreasing the resistance to fluid flow in theshock absorber.

Camber control

See dependent and independent below.

Camber changes due to wheel travel, body roll and suspension system deflection or compliance. In general, atire wears and brakes best at -1 to -2 of camber from vertical. Depending on the tire and the road surface, itmay hold the road best at a slightly different angle. Small changes in camber, front and rear, can be used to tunehandling. Some race cars are tuned with -2 to -7 camber depending on the type of handling desired and the tireconstruction. Often, too much camber will result in the decrease of braking performance due to a reducedcontact patch size through excessive camber variation in the suspension geometry. The amount of camber change in bump is determined by the instantaneous front view swing arm (FVSA) length of the suspensiongeometry, or in other words, the tendency of the tire to camber inward when compressed in bump.

Roll center height

Roll center height is a product of suspension instant center heights and is a useful metric in analyzing weighttransfer effects, body roll and front to rear roll stiffness distribution. Conventionally, roll stiffness distribution istuned adjusting antiroll bars rather than roll center height (as both tend to have a similar effect on the sprungmass), but the height of the roll center is significant when considering the amount of jacking forces experienced.

Instant center

Due to the fact that the wheel and tire's motion is constrained by the suspension links on the vehicle, the motionof the wheel package in the front view will scribe an imaginary arc in space with an "instantaneous center" of rotation at any given point along its path. The instant center for any wheel package can be found by followingimaginary lines drawn through the suspension links to their intersection point.

A component of the tire's force vector points from the contact patch of the tire through instant center. The larger this component is, the less suspension motion will occur. Theoretically, if the resultant of the vertical load on thetire and the lateral force generated by it points directly into the instant center, the suspension links will not move.In this case, all weight transfer at that end of the vehicle will be geometric in nature. This is key information used

in finding the force-based roll center as well.

In this respect the instant centers are more important to the handling of the vehicle than the kinematic roll center alone, in that the ratio of geometric to elastic weight transfer is determined by the forces at the tires and their directions in relation to the position of their respective instant centers.
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Anti-dive and anti-squat

Anti-dive and anti-squat are percentages and refer to the front diving under braking and the rear squatting under acceleration. They can be thought of as the counterparts for braking and acceleration as jacking forces are tocornering. The main reason for the difference is due to the different design goals between front and rear suspension, whereas suspension is usually symmetrical between the left and right of the vehicle.

The method of determining the anti-dive or anti-squat depends on whether the suspension linkages react to thetorque of braking and accelerating. For example, with inboard brakes and half-shaft driven rear wheels, thesuspension linkages do not, but with outboard brakes and a swing-axle driveline, they do.

To determine the percentage of front suspension braking anti-dive for outboard brakes, it is first necessary todetermine the tangent of the angle between a line drawn, in side view, through the front tire patch and the frontsuspension instant center, and the horizontal. In addition, the percentage of braking effort at the front wheelsmust be known. Then, multiply the tangent by the front wheel braking effort percentage and divide by the ratioof the center of gravity height to the wheelbase. A value of 50% would mean that half of the weight transfer tothe front wheels, during braking, is being transmitted through the front suspension linkage and half is being

transmitted through the front suspension springs.

For inboard brakes, the same procedure is followed but using the wheel center instead of contact patch center.

Forward acceleration anti-squat is calculated in a similar manner and with the same relationship between percentage and weight transfer. Anti-squat values of 100% and more are commonly used in dragracing, butvalues of 50% or less are more common in cars which have to undergo severe braking. Higher values of anti-squat commonly cause wheel hop during braking. It is important to note that, while the value of 100%...in either case...means that all of the weight transfer is being carried through the suspension linkage, this does not meanthat the suspension is incapable of carrying additional loads (aerodynamic, cornering, etc.) during an episode of

braking or forward acceleration. In other words, no "binding" of the suspension is to be implied.[5]

Flexibility and vibration modes of the suspension elements

In modern cars, the flexibility is mainly in the rubber bushings. For high-stress suspensions, such as off-roadvehicles, polyurethane bushings are available, which offer more longevity under greater stresses. However, dueto weight and cost considerations, structures are not made more ridged than necessary. Some vehicles exhibitdetrimental vibrations involving the flexing of structural parts, such as when accelerating while turning sharply.Flexibility of structures such as frames and suspension links can also contribute to springing, especially todamping out high frequency vibrations. The flexibility of wire wheels contributed to their popularity in times whencars had less advanced suspensions.

Isolation from high frequency shock

For most purposes, the weight of the suspension components is unimportant, but at high frequencies, caused byroad surface roughness, the parts isolated by rubber bushings act as a multistage filter to suppress noise andvibration better than can be done with only the tires and springs. (The springs work mainly in the verticaldirection.)

Contribution to unsprung weight and total weightThese are usually small, except that the suspension is related to whether the brakes and differential(s) aresprung.
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This is the main functional advantage of aluminum wheels over steel wheels. Aluminum suspension parts have been used in production cars, and carbon fiber suspension parts are common in racing cars.

Space occupied

Designs differ as to how much space they take up and where it is located. It is generally accepted thatMacPherson struts are the most compact arrangement for front-engined vehicles, where space between the

wheels is required to place the engine.

Inboard brakes (which reduce unsprung weight) are probably avoided more due to space considerations than tocost.

Force distribution

The suspension attachment must match the frame design in geometry, strength and rigidity.

Air resistance (drag)

Certain modern vehicles have height adjustable suspension in order to improve aerodynamics and fuel efficiency.Modern formula cars that have exposed wheels and suspension typically use streamlined tubing rather thansimple round tubing for their suspension arms to reduce drag. Also typical is the use of rocker arm, push rod, or

pull rod type suspensions that, among other things, place the spring/damper unit inboard and out of the air stream to further reduce air resistance.

Cost

Production methods improve, but cost is always a factor. The continued use of the solid rear axle, with unsprungdifferential, especially on heavy vehicles, seems to be the most obvious example.

Springs and dampers

Most conventional suspensions use passive springs to absorb impacts and dampers (or shock absorbers) tocontrol spring motions.

Some notable exceptions are the hydropneumatic systems, which can be treated as an integrated unit of gasspring and damping components, used by the French manufacturer Citron and the hydrolastic, hydragas andrubber cone systems used by the British Motor Corporation, most notably on the Mini. A number of differenttypes of each have been used:

Passive suspensions

Traditional springs and dampers are referred to as passive suspensions most vehicles are suspended in thismanner.

Springs

Leaf spring AKA Hotchkiss, Cart, or semi-elliptical springTorsion beam suspensionCoil spring
http://en.wikipedia.org/wiki/Coil_springhttp://en.wikipedia.org/wiki/Torsion_beam_suspensionhttp://en.wikipedia.org/wiki/Leaf_springhttp://en.wikipedia.org/wiki/Minihttp://en.wikipedia.org/wiki/British_Motor_Corporationhttp://en.wikipedia.org/wiki/Hydragashttp://en.wikipedia.org/wiki/Hydrolastichttp://en.wikipedia.org/wiki/Citro%C3%ABnhttp://en.wikipedia.org/wiki/Hydropneumatichttp://en.wikipedia.org/wiki/Shock_absorberhttp://en.wikipedia.org/wiki/Spring_(device)http://en.wikipedia.org/wiki/Height_adjustable_suspensionhttp://en.wikipedia.org/wiki/MacPherson_strut


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Pneumatic spring on a semitrailer

Rubber bushingAir spring

Dampers or shock absorbers

The shock absorbers damp out the (otherwise resonant) motions of avehicle up and down on its springs. They also must damp out much of

the wheel bounce when the unsprung weight of a wheel, hub, axle andsometimes brakes and differential bounces up and down on thespringiness of a tire. Some have suggested that the regular bumpsfound on dirt roads (nicknamed "corduroy", but properly corrugationsor washboarding) are caused by this wheel bounce, though someevidence exists that it is unrelated to suspension at all. (Seewashboarding.)

Semi-active and active suspensions

If the suspension is externally controlled then it is a semi-active or active suspension the suspension isreacting to what are in effect "brain" signals. As electronics have become more sophisticated, the opportunities inthis area have expanded.

For example, a hydropneumatic Citron will "know" how far off the ground the car is supposed to be andconstantly reset to achieve that level, regardless of load. It will not instantly compensate for body roll due tocornering however. Citron's system adds about 1% to the cost of the car versus passive steel springs.

Semi-active suspensions include devices such as air springs and switchable shock absorbers, various self-levelling solutions, as well as systems like hydropneumatic, hydrolastic, and hydragas suspensions. Mitsubishideveloped the worlds first production semi-active electronically controlled suspension system in passenger cars;the system was first incorporated in the 1987 Galant model. [6][7][8][9][10] Delphi currently sells shock absorbersfilled with a magneto-rheological fluid, whose viscosity can be changed electromagnetically, thereby givingvariable control without switching valves, which is faster and thus more effective.

Fully active suspension systems use electronic monitoring of vehicle conditions, coupled with the means toimpact vehicle suspension and behavior in real time to directly control the motion of the car. Lotus Carsdeveloped several prototypes, from 1982 onwards, and introduced them to F1, where they have been fairlyeffective, but have now been banned. Nissan introduced a low bandwidth active suspension in circa 1990 as anoption that added an extra 20% to the price of luxury models. Citron has also developed several activesuspension models (see hydractive). A recently publicised fully active system from Bose Corporation uses linear electric motors (i.e., solenoids) in place of hydraulic or pneumatic actuators that have generally been used upuntil recently. The most advanced suspension system [citation needed ] is Active Body Control, introduced in 1999on the top-of-the-line Mercedes-Benz CL-Class.

Several electromagnetic suspensions have also been developed for vehicles. Examples include theelectromagnetic suspension of Bose, and the electromagnetic suspension developed by prof. Laurentiu Encica.In addition, the new Michelin wheel with embedded suspension working on an electromotor is also similar. [11]

With the help of control system, various semi-active/active suspensions realize an improved design compromiseamong different vibrations modes of the vehicle, namely bounce, roll, pitch and warp modes. However, theapplications of these advanced suspensions are constrained by the cost, packaging, weight, reliability, and/or theother challenges.
http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-11http://en.wikipedia.org/wiki/Electromagnetic_suspensionhttp://en.wikipedia.org/wiki/Mercedes-Benz_CL-Classhttp://en.wikipedia.org/wiki/Active_Body_Controlhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Bose_Corporationhttp://en.wikipedia.org/wiki/Hydractivehttp://en.wikipedia.org/wiki/Nissanhttp://en.wikipedia.org/wiki/Lotus_Carshttp://en.wikipedia.org/wiki/Active_suspensionhttp://en.wikipedia.org/wiki/MR_fluidhttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-10http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-9http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-8http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-7http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-6http://en.wikipedia.org/wiki/Mitsubishi_Galanthttp://en.wikipedia.org/wiki/Mitsubishi_Motorshttp://en.wikipedia.org/wiki/Hydragashttp://en.wikipedia.org/wiki/Hydrolastichttp://en.wikipedia.org/wiki/Hydropneumatichttp://en.wikipedia.org/wiki/Self-levelling_suspensionhttp://en.wikipedia.org/wiki/Air_suspensionhttp://en.wikipedia.org/wiki/Washboardinghttp://en.wikipedia.org/wiki/Washboardinghttp://en.wikipedia.org/wiki/Corduroy_roadhttp://en.wikipedia.org/wiki/Differential_(mechanics)http://en.wikipedia.org/wiki/Unsprung_weighthttp://en.wikipedia.org/wiki/Air_suspensionhttp://en.wikipedia.org/wiki/Bushing_(isolator)http://en.wikipedia.org/wiki/File:Pneumatic_spring.JPG


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Interconnected suspensions

Interconnected suspension, unlike semi-active/active suspensions, could easily decouple different vehiclevibration modes in a passive manner. The interconnections can be realized by various means, such asmechanical, hydraulic and pneumatic. Anti-roll bars are one of the typical examples of mechanicalinterconnections, while it has been stated that fluidic interconnections offer greater potential and flexibility inimproving both the stiffness and damping properties.

Considering the considerable commercial potentials of hydro-pneumatic technology (Corolla, 1996),interconnected hydropneumatic suspensions have also been explored in some recent studies, and their potential

benefits in enhancing vehicle ride and handling have been demonstrated. The control system can also be used for further improving performance of interconnected suspensions. Apart from academic research, an Australiancompany, Kinetic (http://www.kinetic.au.com), is having some success (WRC: 3 Championships, Dakar Rally:2 Championships, Lexus GX470 2004 4x4 of the year with KDSS, 2005 PACE award) with various passiveor semi-active systems, which generally decouple at least two vehicle modes (roll, warp (articulation), pitchand/or heave (bounce)) to simultaneously control each modes stiffness and damping, by using interconnectedshock absorbers, and other methods. In 1999, Kinetic was bought out by Tenneco. Later developments by a

Catalan company, Creuat (http://www.creuat.com) has devised a simpler system design based on single-actingcylinders. After some projects on competition Creuat is active in providing retrofit systems for some vehiclemodels.

Historically, the first mass production car with front to rear mechanical interconnected suspension was the 1948Citron 2CV. The suspension of the 2CV was extremely soft the longitudinal link was making pitch softer instead of making roll stiffer. It relied on extreme antidive and antisquat geometries to compensate for that. Thisredunded into a softer axle crossing stiffness that anti-roll bars would have otherwise compromised. The leadingarm / trailing arm swinging arm, fore-aft linked suspension system together with inboard front brakes had a muchsmaller unsprung weight than existing coil spring or leaf designs. The interconnection transmitted some of the

force deflecting a front wheel up over a bump, to push the rear wheel down on the same side. When the rear wheel met that bump a moment later, it did the same in reverse, keeping the car level front to rear. The 2CV hada design brief to be able to be driven at speed over a ploughed field. It originally featured friction dampers andtuned mass dampers. Later models had tuned mass dampers at the front with telescopic dampers / shock absorbers front and rear.

The British Motor Corporation was also an early adopter of interconnected suspension. A system dubbedHydrolastic was introduced in 1962 on the Morris 1100 and went on to be used on a variety of BMC models.Hydrolastic was developed by suspension engineer Alex Moulton and used rubber cones as the springingmedium (these were first used on the 1959 Mini) with the suspension units on each side connected to each other

by a fluid filled pipe. The fluid transmitted the force of road bumps from one wheel to the other (on the same principle as the Citroen 2CV's mechanical system described above) and because each suspension unit containedvalves to restrict the flow of fluid also served as a shock absorber. [12] Moulton went on to develop areplacement for Hydrolastic for BMC's successor, British Leyland. This system, called Hydragas worked on thesame principle but instead of rubber spring units it used metal spheres divided internally by a rubber diaphragm.The top half contained pressurised gas and the lower half the same fluid as used on the Hydrolastic system. Thefluid transmitted suspension forces between the units on each side whilst the gas acted as the springing mediumvia the diaphragm. This is the same principle as the Citroen hydropneumatic system and provides a similar ridequality but is self-contained and doesn't require an engine-driven pump to provide hydraulic pressure. Thedownside is that Hydragas is, unlike the Citroen system, not height adjustable or self-levelling. Hydragas wasintroduced in 1973 on the Austin Allegro and was used on several models, the last car to use it being the MG Fin 2002.

Some of the last post-war Packard models also featured interconnected suspension.
http://en.wikipedia.org/wiki/Packardhttp://en.wikipedia.org/wiki/MG_F_/_MG_TFhttp://en.wikipedia.org/wiki/Austin_Allegrohttp://en.wikipedia.org/wiki/Hydropneumatic_suspensionhttp://en.wikipedia.org/wiki/Hydrolastic#Hydragashttp://en.wikipedia.org/wiki/British_Leylandhttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-12http://en.wikipedia.org/wiki/Shock_absorberhttp://en.wikipedia.org/wiki/Minihttp://en.wikipedia.org/wiki/Alex_Moultonhttp://en.wikipedia.org/wiki/BMC_ADO16http://en.wikipedia.org/wiki/Hydrolastichttp://en.wikipedia.org/wiki/British_Motor_Corporationhttp://en.wikipedia.org/wiki/Shock_absorberhttp://en.wikipedia.org/wiki/Tuned_mass_damperhttp://en.wikipedia.org/wiki/Tuned_mass_damperhttp://en.wikipedia.org/wiki/Unsprung_weighthttp://en.wikipedia.org/wiki/Trailing_armhttp://en.wikipedia.org/wiki/Citro%C3%ABn_2CVhttp://www.creuat.com/http://en.wikipedia.org/wiki/Dakar_Rallyhttp://en.wikipedia.org/wiki/World_Rally_Championshiphttp://www.kinetic.au.com/http://en.wikipedia.org/wiki/Hydropneumatic_suspension


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Common types seen from behind; inorder:

Live axle with Watt bar Suspension like on a bike fork Swing axleDouble wishboneMacPherson

This diagram is not exhaustive;

notably excluding elements such astrailing arm links and those that areflexible.

Suspension geometry

Suspension systems can be broadly classified into two subgroups:dependent and independent. These terms refer to the ability of opposite wheels to move independently of each other.

A dependent suspension normally has a beam (a simple 'cart' axle)

or (driven) live axle that holds wheels parallel to each other and perpendicular to the axle. When the camber of one wheel changes,the camber of the opposite wheel changes in the same way (byconvention on one side this is a positive change in camber and on theother side this a negative change). De Dion suspensions are also inthis category as they rigidly connect the wheels together.

An independent suspension allows wheels to rise and fall on their own without affecting the opposite wheel. Suspensions with other devices, such as sway bars that link the wheels in some way are still

classed as independent.

A third type is a semi-dependent suspension. In this case, the motionof one wheel does affect the position of the other but they are notrigidly attached to each other. A twist-beam rear suspension is such asystem.

Dependent suspensions

Dependent systems may be differentiated by the system of linkagesused to locate them, both longitudinally and transversely. Often bothfunctions are combined in a set of linkages.

Examples of location linkages include:

Satchell link Panhard rodWatt's linkageWOBLink Mumford linkageLeaf springs used for location (transverse or longitudinal)

Fully elliptical springs usually need supplementarylocation links and are no longer in common useLongitudinal semi-elliptical springs used to be commonand still are used in heavy-duty trucks and aircraft. Theyhave the advantage that the spring rate can easily bemade progressive (non-linear).A single transverse leaf spring for both front wheelsand/or both back wheels, supporting solid axles, was

used by Ford Motor Company, before and soon after World War II, even on expensive models. It had theadvantages of simplicity and low unsprung weight(compared to other solid axle designs).
http://en.wikipedia.org/wiki/World_War_IIhttp://en.wikipedia.org/wiki/Ford_Motor_Companyhttp://en.wikipedia.org/wiki/Leaf_springhttp://en.wikipedia.org/w/index.php?title=Mumford_linkage&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=WOBLink&action=edit&redlink=1http://en.wikipedia.org/wiki/Watt%27s_linkagehttp://en.wikipedia.org/wiki/Panhard_rodhttp://en.wikipedia.org/w/index.php?title=Satchell_link&action=edit&redlink=1http://en.wikipedia.org/wiki/Twist-beam_rear_suspensionhttp://en.wikipedia.org/wiki/Sway_barhttp://en.wikipedia.org/wiki/Independent_suspensionhttp://en.wikipedia.org/wiki/De_Dion_tubehttp://en.wikipedia.org/wiki/Camber_anglehttp://en.wikipedia.org/wiki/Live_axlehttp://en.wikipedia.org/wiki/Beam_axlehttp://en.wikipedia.org/wiki/File:Automotive_suspension_comparison.svg


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A rear independent suspension on anAWD car.

In a front engine, rear-drive vehicle, dependent rear suspension is either "live axle" or deDion axle, depending onwhether or not the differential is carried on the axle. Live axle is simpler but the unsprung weight contributes towheel bounce.

Because it assures constant camber, dependent (and semi-independent) suspension is most common on vehiclesthat need to carry large loads as a proportion of the vehicle weight, that have relatively soft springs and that donot (for cost and simplicity reasons) use active suspensions. The use of dependent front suspension has becomelimited to heavier commercial vehicles.

Semi-independent suspension

In a semi-independent suspensions, the wheels of an axle are able to move relative to one another as in anindependent suspension but the position of one wheel has an effect on the position and attitude of the other wheel. This effect is achieved via the twisting or deflecting of suspension parts under load. The most commontype of semi-independent suspension is the twist beam.

Twist beam

Independent suspension

Main article: Independent suspension

The variety of independent systems is greater and includes:

Swing axleSliding pillar MacPherson strut/Chapman strut

Upper and lower A-arm (double wishbone)Multi-link suspensionSemi-trailing arm suspensionSwinging armLeaf springsTransverse leaf springs when used as a suspension link, or four

quarter elliptics on one end of a car are similar to wishbones in geometry, but are more compliant.Examples are the front of the original Fiat 500, the Panhard Dyna Z and the early examples of Peugeot 403 and the back of the AC Ace and AC Aceca.

Because the wheels are not constrained to remain perpendicular to a flat road surface in turning, braking andvarying load conditions, control of the wheel camber is an important issue. Swinging arm was common in smallcars that were sprung softly and could carry large loads, because the camber is independent of load. Someactive and semi-active suspensions maintain the ride height, and therefore the camber, independent of load. Insports cars, optimal camber change when turning is more important.

Wishbone and multi-link allow the engineer more control over the geometry, to arrive at the best compromise,than swing axle, MacPherson strut or swinging arm do; however the cost and space requirements may begreater. Semi-trailing arm is in between, being a variable compromise between the geometries of swinging arm

and swing axle.

Tracked vehicles
http://en.wikipedia.org/wiki/Sports_carhttp://en.wikipedia.org/wiki/AC_Acecahttp://en.wikipedia.org/wiki/AC_Acehttp://en.wikipedia.org/wiki/Peugeot_403http://en.wikipedia.org/wiki/Panhard_Dyna_Zhttp://en.wikipedia.org/wiki/Fiat_500http://en.wikipedia.org/wiki/Semi-trailing_arm_suspensionhttp://en.wikipedia.org/wiki/Multi-link_suspensionhttp://en.wikipedia.org/wiki/Double_wishbonehttp://en.wikipedia.org/wiki/A-armhttp://en.wikipedia.org/wiki/Chapman_struthttp://en.wikipedia.org/wiki/MacPherson_struthttp://en.wikipedia.org/wiki/Sliding_pillarhttp://en.wikipedia.org/wiki/Swing_axlehttp://en.wikipedia.org/wiki/Independent_suspensionhttp://en.wikipedia.org/wiki/Twist-beam_rear_suspensionhttp://en.wikipedia.org/wiki/DeDion_axlehttp://en.wikipedia.org/wiki/Four-wheel_drivehttp://en.wikipedia.org/wiki/File:Independent_rear_suspension_AWD.jpg


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This Grant I tank's suspension hasroad wheels mounted on wheel

trucks, or bogies .

Some vehicles such as trains run on long rail tracks fixed to the ground, and some such as tractors, snowvehicles and tanks run on continuous tracks that are part of the vehicle. Though either sort helps to smooth the

path and reduce ground pressure, many of the same consideration apply.

Armoured fighting vehicle suspension

Military AFVs, including tanks, have specialized suspensionrequirements. They can weigh more than seventy tons and are required tomove as quickly as possible over very rough or soft ground. Their suspension components must be protected from land mines and antitank weapons. Tracked AFVs can have as many as nine road wheels on eachside. Many wheeled AFVs have six or eight large wheels. Some have aCentral Tire Inflation System to reduce ground loading on poor surfaces.Some wheels are too big and confined to turn, so skid steering is usedwith some wheeled, as well as with tracked, vehicles.

The earliest tanks of World War I had fixed suspension with no designedmovement whatsoever. This unsatisfactory situation was improved withleaf spring or coil spring suspensions adopted from agricultural,automotive or railway machinery, but even these had very limited travel.

Speeds increased due to more powerful engines, and the quality of ride had to be improved. In the 1930s, theChristie suspension was developed, which allowed the use of coil springs inside a vehicle's armored hull, bychanging the direction of force deforming the spring, using a bell crank. The war winning T-34 was directlydescended from Christie designs. Horstmann suspension was a variation which used a combination of bell crank and exterior coil springs, in use from the 1930s to the 1990s. The bogie, but nonetheless independent,suspension of the M3 Lee/Grant and the M4 Sherman was similar to the Hortsmann type, with the suspensioncontained within the track oval.

By World War II the other common type was torsion bar suspension, getting spring force from twisting barsinside the hull this sometimes had less travel than the Christie-type, but was significantly more compact,allowing more space inside the hull, with consequent possibility to install larger turret rings and thus a heavier main armament. The torsion-bar suspension, sometimes including shock absorbers, has been the dominantheavy armored vehicle suspension since World War II. Torsion bars may take space under or near the floor,which may interfere with making the tank low to reduce exposure.

As with cars, wheel travel and spring rate affect the bumpiness of the ride and the speed at which rough terraincan be negotiated. It may be significant that sooth ride, which is often associated with comfort, increases theaccuracy when firing on the move (analogously to battle ships with reduced stability, due to reduced metacentricheight). It also reduces shock on optics and other equipment. The unsprung weight and track link weight maylimit speed on roads and affect the life of the track and other components.

Most German WW II half tracks and their tanks introduced during the war such as the Panther tank hadoverlapping and sometimes interleaved road wheels to distribute the load more evenly on the track and thereforeon the ground. This apparently made a significant contribution to speed, range and track life, as well as providinga continuous band of protection. It has not been used since the end of that war, probably due to themaintenance requirements of more complicated mechanical parts working in mud, sand, rocks, snow and ice, aswell as to cost. Rocks and frozen mud stuck between the wheels. [13]

See also
http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_note-13http://en.wikipedia.org/wiki/Panther_tankhttp://en.wikipedia.org/wiki/Unsprung_weighthttp://en.wikipedia.org/wiki/Metacentric_heighthttp://en.wikipedia.org/wiki/Torsion_bar_suspensionhttp://en.wikipedia.org/wiki/World_War_IIhttp://en.wikipedia.org/wiki/M4_Shermanhttp://en.wikipedia.org/wiki/M3_Leehttp://en.wikipedia.org/wiki/Bogiehttp://en.wikipedia.org/wiki/Horstmann_suspensionhttp://en.wikipedia.org/wiki/T-34http://en.wikipedia.org/wiki/Bell_crankhttp://en.wikipedia.org/wiki/Coil_springhttp://en.wikipedia.org/wiki/Christie_suspensionhttp://en.wikipedia.org/wiki/Coil_springhttp://en.wikipedia.org/wiki/Leaf_springhttp://en.wikipedia.org/wiki/World_War_Ihttp://en.wikipedia.org/wiki/Central_Tire_Inflation_Systemhttp://en.wikipedia.org/wiki/Wheelhttp://en.wikipedia.org/wiki/Continuous_trackhttp://en.wikipedia.org/wiki/Antitankhttp://en.wikipedia.org/wiki/Land_minehttp://en.wikipedia.org/wiki/Tankhttp://en.wikipedia.org/wiki/Armoured_fighting_vehiclehttp://en.wikipedia.org/wiki/Continuous_trackhttp://en.wikipedia.org/wiki/Track_(rail_transport)http://en.wikipedia.org/wiki/Bogiehttp://en.wikipedia.org/wiki/M3_Granthttp://en.wikipedia.org/wiki/File:M3Grant.jpg


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4-poster a test rig7 post shaker a test rig for high speed vehiclesAutomobile handling transverse performanceAutomotive suspension design the design processActive suspension powered suspensionBicycle fork bicycle front suspensionBicycle suspension especially separate springs

Bump Steer reaction to road surfaceCamber angle wheel tiltCaster angle self centering steeringChapman strut a type of rear suspensionCitron 2CV a successful vehicle with unusual suspension type and performanceClassical mechanics a field of physicsContinuous track device to reduce the ground loading of off-roadDouble wishbone suspension or A arm, maximum independent design freedomKinematics physics of the geometry of motion

MacPherson strut a type of front suspensionMagnetic levitation and maglev train may involve superconductorsMotorcycle fork front suspension of a motorcyclePanther tank early modern, and in ways unique heavy off-road suspensionRoll center the axis that is not moved by a sideways forceScrub radiusShock absorber device to damp repetitive motion by absorbing energyShort long arms suspension or "unequal length A arm", one of the design parameters of double wishbonesuspensionStrut bar a form of semi-independent suspensionSuspension (motorcycle) different principles than 3 or more wheelsSway bar or anti-roll bar, stiffens roll resistance, semi-independentTire or tyre, the outer part of a wheelUnsprung mass the part closer to the road than the springs areWheel Wheels are unsprung, except by the tires, and may flex.

References

1. ^ Reza N. Jazar (2008). Vehicle Dynamics: Theory and Applications (http://books.google.com/books?id=Pvsv78xj7UIC&printsec=frontcover&dq=vehicle+dynamics&hl=en&sa=X&ei=Rr3nT8KaO4Oq2QX016jaCQ&ved=0CDcQ6AEwAA#v=onepage&q=suspension&f=false). Spring. p. 455. Retrieved 2012-06-24.

2. ^ Adams, William Bridges (1837). English Pleasure Carriages (http://books.google.co.uk/books?id=apw7AAAAMAAJ). London: Charles Knight & Co.

3. ^ "The Washington Times, Sunday 30 June 1901" (http://chroniclingamerica.loc.gov/lccn/sn87062245/1901-06-30/ed-1/seq-1/;words=Paris+races+Berlin+race+Race). Chroniclingamerica.loc.gov. Retrieved 2012-08-16.

4. ^ Jain, K.K.; R.B. Asthana. Automobile Engineering . London: Tata McGraw-Hill. pp. 293294. ISBN 0-07-044529-X.

5. ^ Pages 617-620 (particularly page 619) of "Race Car Vehicle Dynamics" by William and Douglas Milliken6. ^ "Mitsubishi Galant" (http://www.mitsubishi-motors.co.za/featuresites/mm_history/Galant.asp), Mitsubishi

Motors South Africa website7. ^ "Mitsubishi Motors history 1981-1990" (http://www.mitsubishi-motors.co.za/featuresites/mm_history/1980-

1989.asp), Mitsubishi Motors South Africa website8. ^ "Technology DNA of MMC" (http://www.mitsubishi-

motors.com/corporate/about_us/technology/review/e/pdf/2005/17e_02.pdf), .pdf file, Mitsubishi Motors
http://www.mitsubishi-motors.com/corporate/about_us/technology/review/e/pdf/2005/17e_02.pdfhttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-8http://www.mitsubishi-motors.co.za/featuresites/mm_history/1980-1989.asphttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-7http://www.mitsubishi-motors.co.za/featuresites/mm_history/Galant.asphttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-6http://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-5http://en.wikipedia.org/wiki/Special:BookSources/0-07-044529-Xhttp://en.wikipedia.org/wiki/International_Standard_Book_Numberhttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-4http://chroniclingamerica.loc.gov/lccn/sn87062245/1901-06-30/ed-1/seq-1/;words=Paris+races+Berlin+race+Racehttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-3http://books.google.co.uk/books?id=apw7AAAAMAAJhttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-2http://books.google.com/books?id=Pvsv78xj7UIC&printsec=frontcover&dq=vehicle+dynamics&hl=en&sa=X&ei=Rr3nT8KaO4Oq2QX016jaCQ&ved=0CDcQ6AEwAA#v=onepage&q=suspension&f=falsehttp://en.wikipedia.org/wiki/Suspension_(vehicle)#cite_ref-1http://en.wikipedia.org/wiki/Wheelhttp://en.wikipedia.org/wiki/Unsprung_masshttp://en.wikipedia.org/wiki/Tirehttp://en.wikipedia.org/wiki/Sway_barhttp://en.wikipedia.org/wiki/Suspension_(motorcycle)http://en.wikipedia.org/wiki/Strut_barhttp://en.wikipedia.org/wiki/Short_long_arms_suspensionhttp://en.wikipedia.org/wiki/Shock_absorberhttp://en.wikipedia.org/wiki/Scrub_radiushttp://en.wikipedia.org/wiki/Roll_centerhttp://en.wikipedia.org/wiki/Panther_tankhttp://en.wikipedia.org/wiki/Motorcycle_forkhttp://en.wikipedia.org/wiki/Maglev_trainhttp://en.wikipedia.org/wiki/Magnetic_levitationhttp://en.wikipedia.org/wiki/MacPherson_struthttp://en.wikipedia.org/wiki/Kinematicshttp://en.wikipedia.org/wiki/Double_wishbone_suspensionhttp://en.wikipedia.org/wiki/Continuous_trackhttp://en.wikipedia.org/wiki/Classical_mechanicshttp://en.wikipedia.org/wiki/Citro%C3%ABn_2CVhttp://en.wikipedia.org/wiki/Chapman_struthttp://en.wikipedia.org/wiki/Caster_anglehttp://en.wikipedia.org/wiki/Camber_anglehttp://en.wikipedia.org/wiki/Bump_Steerhttp://en.wikipedia.org/wiki/Bicycle_suspensionhttp://en.wikipedia.org/wiki/Bicycle_forkhttp://en.wikipedia.org/wiki/Active_suspensionhttp://en.wikipedia.org/wiki/Automotive_suspension_designhttp://en.wikipedia.org/wiki/Automobile_handlinghttp://en.wikipedia.org/wiki/7_post_shakerhttp://en.wikipedia.org/wiki/4-poster


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technical review 20059. ^ "MMC's new Galant." (http://www.accessmylibrary.com/coms2/summary_0286-26567890_ITM), Malay

Mail, Byline: Asian Auto, Asia Africa Intelligence Wire, 16-SEP-02 (registration required)10. ^ "Mitsubishi Motors Web Museum" (http://www.mitsubishi-

motors.com/corporate/museum/history/1980/e/index.html), Mitsubishi Motors website11. ^ "Electromagnetic suspension" (http://www.amt.nl/web/Nieuws/Autotechniek/Tonen-Nieuws-

Autotechniek/Zwevend-over-de-weg-met-magneetvering.htm). Amt.nl. 2008-11-19. Retrieved 2012-08-16.12. ^ "Alex Moulton Mgf Hydragas" (http://www.mgfcar.de/hydragas/moulton.htm). Mgfcar.de. Retrieved 2012-

08-16.13. ^ Peter Chamberlain and Hilary Doyle, Encyclopedia of German Tanks of World War Two , 1978, 1999

External links

How Car Suspensions Work (http://auto.howstuffworks.com/car-suspension.htm)Robert W. Temple, The ABCs of Chassis Frame and Suspensions , September 1969(http://books.google.co.uk/books?id=M9gDAAAAMBAJ&pg=PA128&lpg=PA90&dq=gyrocopter+ejection+seat&source=bl&ots=F6X

dY0Bwxr&sig=D-qy0YIKOrhLBxDFV7- jbgpwi8o&hl=en&ei=kYKGTNG4Ksf84Abll6jSBA&sa=X&oi=book_result&ct=result&resnum=9&ved=0CDcQ6AEwCA#v=onepage&q=gyrocopter%20ejection%20seat&f=true)Suspension Geometry Calculator (http://www.racingaspirations.com/suspensiongeometry.php)

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