History Of Suspension System Engineering Essay

History Of prison-breaking System Engineering testifyFor my assignment, I ordain be talking roughly interruption. I ordain explain everything from the early study of the time out form, the research and development, the differences of each severance towards application, and so on. The main(prenominal) why the assignment has been done is beca accustom it train us and tells us each(prenominal) sorts of things that is in all about reprieve and why is has build in a lot(prenominal) a way that the temporary removal should perform depending on the display case of motorcars.History of prisonbreak SystemThe int celestial poleuctory good luck to be introduced is from horse-drawn carriages in the 19th century. It parts a aggregate layer of steels, or in some cases, use wood as a throttle. It is known as a alternate spring. As late cars were object to move at a fast-paced speed, obstaclee-ass type of rest ar needed. In the early 1900s, horrify absorber were b eing introduced in cars by a guy nameThe social occasion and the Purpose of a Suspension SystemThe main role of a prison-breaking formation is to observe a maximum contact between the tyres and the avenue surface, to gist steering stability and also to provide unattackable treatment during low-speed and high-speed corners. The abeyance helps to gene mark as much traction as possible, depending on the device driver and how the driver handle the cars suspension ashes and helps to minimize the bole roll resistance. It helps to iso young the body from the vibrations of the appal absorbers. Roads that currently exist be non flat and straight. If the roads atomic number 18 all flat and straight, thithers no point installing a suspension system for cars. When roads atomic number 18 not flat, theres a force reacting on the jar absorber and the springs through the wheel. According to Newtons law of motion, all forces corrobo browse some(prenominal) magnitude and directio n. The separate main importance of a suspension system is that help to provide a correct alignment during steering, to dishonor the beat of body roll, to allow the driver to turn corner precipitously without extreme body roll and to prevent body dive, that is to mow the body to tilt up and cumulation during quickening and braking. Two main components argon responsible to all these kind of job that is shock absorber and spring. recantThe function of the spring is to support the exercising weight of the vehicle, and to absorb road shocks being transferred from the wheels. The spring bounces up and reduce when de disperseure through holes, blows, and uneven road surfaces. thither be all sorts of springsC oil- It is do out of a special steel rod, which is made by winding a wire around a cylinder. It is just about comm exactly employ in light vehicles. The wire will twist when the drum roll is being matt or stretched. The approach pattern of a coil spring can be a cyli ndrical, barrel or conical do, depending on what kind of spring that argon required for the type of the car. The material utilise for springs have to be capable of withstanding high stress and resisting fatigue. In early number, designers use high-carbon steel, solely today, designers use a very minimum get along of alloy steel such(prenominal) as silico-manganese are use.Leaf Spring- It has several(prenominal) flexible tempered p new-fashioneds with different length, which is stacked and being held by a steel clip. It is mainly use on stir-wheel drive vehicles, such as 4 wheel drive. The function is the same as the coil, solely the only difference is that the leaf has minimum amount of flexibleness than the coil. The stiffness or rate of a leaf spring is governed byLength of the spring- the length of the spring, the rate of the suspensionWidth of the leaf- the comprehensiveness of the spring, the rate of the suspensionThickness of the leaf- the thickness of the leaf, t he rate of the suspensionNumber of leaves- the amount of leaves, the rate of the suspensiondeformation Bar- A deformation bar is a prospicient straight alloy-steel bar, fixed between the conformation to the suspension control section. The torsion bar will twist at the centre of the bar when the spring moves upward(a) and downward. The spring rate varies the length and the diameter of the bar. When the driver turns the wheel, the torsion bar will twist, and reduces the roll tendency. diffuse Spring- It is a guard cylinder, filled with compressed air. This kind of spring is being used in serious commercial vehicles and luxury cars. It provides comfort compared to the coil spring. The volume of air is being varied, depending on the load of the vehicle being added, to lower the vehicle, and go adjust the stiffness of the air spring.Rubber Spring- It is used as the main suspension spring, or fitted with a metal springs to improve / upgrade the suspension characteristics.Shock Abso rberThe function of a shock absorber is to help dampen the amount of bounce created by the spring. The absorber gives the spring the freedom of bounce, nevertheless shock absorber is there to help dampen the undesired amount of bounce and thus, create stability of the vehicle. Here are the few types of shock absorber being used currently on the roadsHydraulic Shock Absorber- just about of the vehicles are using this kind of shock absorber. It is called a direct-acting telescopic type. Its damping action is being produced by the oil transfer, which is beneath nip, and goes through the small valve which helps to restrict the oil flowing in and out. The most widely used is the twin- tobacco pipe-shaped structure type. During compression, the speculator moves towards the shock absorber. And during rebound, its a complete frigid.Gas-Pressurized Shock Absorber- In the hydraulic shock absorber, the oil heats up as the suspension is in motion. This shock absorber helps to reduce th e dissolve pressure by using melted with atomic number 7. This improves the dampening effect, thus improves the absorbers act.Load-Adjustable Shock Absorber- This type of absorber helps to pressurize the shock absorber when the springs are under load. By adjusting the pressure, it helps to swear the car visor and adjusting the suspension stiffness. This helps to reduce the soreness of the driver and the passenger. In order to reduce the discomfort of the driver and the passenger, the driver can adjust the air spring manually. The construction is almost as uniform as the air spring, where you can adjust the mount up height and the stiffness of the absorber.Manual Adjustable-Rate Shock Absorber- The adjustable-rate absorber has a ingest where you can change the spring oscillations by changing the rate of dampening. It has a damper rate adjustment placed on the external of the shock absorber. You can control the restriction of the oil passing through by changing the valves in the diver.Electronic Adjustable-Rate Shock Absorber- It acts the same as the manual adjustable-rate shock absorber. The only different between the manual and the electronic is that the rate of the shock absorber can be controlled electronically or by drivers choice. This is a solenoid operated with the help of the ECU, which allows different types of modes to choose.Automatic Load-Adjustable Shock Absorber- Also called as self-leveling shock absorber. When theres load on the vehicle, the shock absorber will self maintain at a pre-set level. It automatically adjusts the height of the vehicle, depending on the load added at the rear axle. It consists of air-adjustable shock absorbers fitted at the rear, an air-dryer manufacturing, ECU, and an electrically-driven compressor.Types of Suspension SystemThere are all sorts of suspension system being used today, and they areNon- self-supporting SuspensionSolid / Live and exsanguinous / Beam axle suspension systemA Live axle is an old tec hnology. It is a combination of a unscathed axle being put a comprehend the cars chassis, which is being connected at twain front and the back of the wheels. This suspension is not independent, so when 1 wheel goes through a hump, the shock produced on that wheel will be transferred to the other wheel. This Live / Solid axle suspension consists of a drive shaft, a differential, and a vehement pipework enclosing all these things. The unsprung weight for this kind of suspension is very high because the whole axle assembly is fixed bolt to the wheels. The result of an unsprung weight is that the more weight it gains, the momentum is higher. So in this case, a clutch of momentum the springs have to handle because springs cannot absorb momentum, so therefore part of the momentum has to be transferred to the car body in a shock form. Because of this, this kind of axle does not provide a good ride caliber.In the Dead / Beam axle, theres not driving axle on it, so therefore it has a very minimum amount of unsprung weight and it produces get out ride timberland than a zippy axle.vantageDisadvantageCheapIts not independentBody roll does not interfere with the banking concern of the wheelsTheres no ride qualitySimple constructionThe size is not practicalWhen one wheel has a force on it, the force is being transferred to the other wheelDeDion axle suspension systemIn the late 70s, non-independent suspension market is stronger than the independent suspension, although the independent suspension were invented many years ago. The main reason why is because non-independent suspension is cheaper and offers better handling than the independent suspension. In this suspension, it helps to eliminate all the unsprung weight rather than the live axle suspension. It has minimum amount of unsprung weight is because the differential / final drive and the drive shafts are not rigidly attached to the rear wheels and therefore they are part of the car body and its flexibility to the wheels with the help of the ecumenic joints. By using the DeDion technology, it helps to improve the ride quality by limit the wheel track stochastic variable when the suspension is at motion. In order to do this, the DeDion technology uses a sliding joint. The best part of using this is that it is always perpendicular to the road surface by keeping two wheels on the road surface, excluding the body roll. benefitDisadvantageCheaper than most independent suspensionIts not a independent suspensionThe camber are not being affected even with body rollThe ride quality is not as good as the independent suspensionThe ride quality is more top-flight than the live axle suspensionWhen the car is on a bump, both of the rear wheels will be camberedSemi-Independent SuspensionTwist- carry rear suspensionIt is based on a large H shaped member. The front of the H shaped member is being attached to the chassis with the help of rubber bushings and the rear of the H shaped member is attache d to the wheels. The H manage to get the support by using the cross beam. The cross beam serves as to provide roll stiffness during corner and bump. It has a twisting action when both tracking arms move vertically. Coil springs and shock absorbers are being used in this system, located either behind, or alongside with the wheels. It provides high motion ratio and the end result, giving better performance and the weight reduction. The location of the cross beam is longitudinal as the roll steer control and its camber compliance.Independent SuspensionSwing axle suspension systemIts an old suspension, first introduced by some sports cars in 1950s. This kind of technology has been phased out in 2 decades due to its weaknesses. The adjustment of the camber angles can be detuned by changing to a longer swinging arm. Usually, this kind of technology serves a lot of under steer, so by setting the wheels to a negative camber, it helps to reduce the unnecessary amount of under steer. preferD isadvantageProvides an Independent shock preoccupancyProvides a very bad handling during cornerSo much body rollTends to oversteer a lotTrailing / Leading arm suspension systemA large piece of suspension that helps to support the coil springs, which are being located in front of the rear axle and connected to the axle of the cars chassis. The main role of this kind of suspension is to allow the wheels to move up and down and this does not allow the camber to change. The only time the camber changes during corners. The advantage and the disadvantage are the same as the semi-trailing arm suspension.Semi-trailing arm suspension systemIn this design of suspension, compare to the trailing / leading arm suspension, its pivoted in an incline angles, roughly in between 50 to 70 degrees. The feature of the suspension is the same with the trailing / leading arm suspension. In both semi-trailing and the trailing / leading arm suspension are rigidly attached to the wheels. So when taking corner or taking bump aggressively shocks and noises will be transferred to the cars chassis. just now now days, self-propelling industry are moving to multi-link or double wishbone suspension. So therefore, the trailing / leading and semi-trailing arm suspension is going to be phased out.AdvantageDisadvantageIts an all rounder, not much weaknessDetuned version of multi-link suspensionUndersteer, but not muchWhen the wheels are moving up and down, the camber angle changesShocks and noise are being transferred to the cars chassis adjustive air suspension systemIt uses air suspension rather than using the conventional shock absorber and coil spring. You can electronically changes the damping rates to suit the driving conditions. The air suspension inflates and deflates depending on the driver brave the driver choose the height of the car.AdvantageDisadvantageProvide accurate handlingExpensive splitCapable of handling heavy loadAdjustable height and spring rateTorsion beam suspension syst emMajority of the small car segment uses this kind of suspension. Its half-independent, which consist of a torsion bar, which is being used to limit the degree of freedom when force is being produced when taking in a corner. Its more superior to its competitor, care the MacPherson tittup suspension.AdvantageDisadvantageProvides more leg room for the rear seat of the car and more space for the bootDoesnt provide the same ride and height quality as the double wishbone or the multi-link suspensionCheapLimited amount of freedom thriving to maintainInferior in ride and handling qualityDouble wishbone suspension systemIn this era, many sports car such as Lotus, Ferrari, and all the famous top marquee car brands, are using this kind of suspension system because it can be used at both front and rear wheels, and to top it all off, it has almost near perfect camber control. Its has long been used in racing, sport and top of the range cars for more than 40 years as it provides better and pre cise control. Its main role is to maintain the wheel perpendicular with the road surface, no matter how aggressive the driver handle the car. In the early days of double wishbone, it consists of 2 parallel wishbone arms in equal length. The main problem with this is that the tyres are producing excessive scrubbing due to the variable track width when the wheels are shifted off from the neutral position. So manoeuvers have given a best solution, which is to develop inadequate length and non-parallel A-arms to solve the problem. By doing this, the engineers tilted up the upper arm. The shock absorbers and the coil springs are installed onto the wishbones because it helps the engineer to adjust camber and caster angle, toe, roll centre height and scrub radius. The reason why 1 wishbone is compendiouser than the other is because to make the camber negative. The shorter wishbone is installed on the upper mount. When it sets to a negative camber, the result is a positive camber gain on the outer wheel when the vehicle is turning. not only that, the outside wheel gains back negative camber due to shorter upper arm.AdvantageDisadvantage beseeming camber controlNot space savingProvides good handlingExpensiveLow unsprung weightA lot of components and needs more pick up points in the cars chassisStrongMacPherson strut Chapman strut suspension systemInvented by a guy the name of Earl S. MacPherson in the 1940s. Ford started to use this kind of technology in the 1950 because of its low cost and space saving and thus, MacPherson is one of the dominating suspension system. In the design, the telescopic shock absorber purpose is control the wheel position, and because of this, it doesnt require an upper arm. It is very coalition because the strut is build vertically. Many front wheel drive and compact cars inherit this kind of suspension system because of the space being occupied by the engine and the transmission. This design is not suitable in sports and performance car as its height requires a higher hood and fender line. And because of this, it doesnt provide a good handling and it has a little camber change, unlike the double wishbone suspension. MacPherson can be used in both front and rear wheels. Another kind of strut is the Chapman strut being introduced by a guy name Colin Bruce Chapman, founder of Lotus. Its another kind of Independent Rear Suspension (IRS) that is using a lateral link with a long spring strut. The features are the same as the MacPherson and its used for the rear of the wheels. Only some model such as Lotus and the Datsun are using this suspension but it has already being phased out.AdvantageDisadvantageSmall and compactProvides an average handlingCheap and easy to maintainCamber change due to body rollSimple designExcessive heightMulti-link suspension systemThis kind of suspension system is being introduced in the late 1980s. More modern cars are using this kind of suspension system as it is independent suspension system , uses a minimum amount of short links being attached to the hub carrier and to the body, and it developed a consistent handling and traction. Its mainly used in rear wheels, not the front wheels. It helps to allow the man-to-man wheel in the rear of the cart to move freely during bumps and uneven roads without affecting the opposite wheel. But during the Research Development of the cars, most manufacture favors MacPherson struts, swing axle and trailing arm because of its disadvantage of the suspension system. The multi-link suspension uses a few amounts of short links, being attached to the cars chassis. The link are being used to eliminate the changes of the camber angle during movement, and to control the Toe and Caster depending on the geometry design of the link. Some manufacturers use 3, or possibly up to 5 links to provide better performance. This kind of suspension is expensive, but an Italian company named Magneti Marelli, are developing a cost-effective multi-link suspe nsion for small cars. In their new design, it uses a flexible links to reduce the cost and use a simple bushing to reduce noise being transmitted to the cockpit.AdvantageDisadvantageProvides good handlingMore expensive than the MacPherson and torsion beamProvides good ride comfortNot compactPoor camber control bowed down(p)Too complexLeaf suspension systemLeaf suspension is the oldest suspension in the automotive industry. And today, there are still cars that are using leaf spring, mainly for 44, trucks, and other heavy vehicles. The leaf suspension makes its way in production in the 70s. Even some race cars are using leaf suspension system but only in dirt and asphalt. There are 4 kinds of leaf being introduced, and they areThe monoleaf The spring is thin and provides a low rate shocks. But in this design, it requires an additional support of springs because monoleaf is not sufficient enough to support the additional load.Multileaf Its made up to multiple layers of leaves with diff erent length. Many 44 are using this kind of suspension as it provides higher spring rate and manage to support and control the axle.AdvantageDisadvantageCapable of supporting the weight of the chassisThe steel tends to lose its shapeAble to control the chassis roll more efficientThe handling will be affected when the sag is unevenManage to control the rear end wrap-up and axle dampingNot much adjustmentCapable of controlling the lateral forces produced by the car, the same feature as the panhard barHard to installManage to withstand braking forcesNot much dampening so therefore, the ride will become stiffDuring acceleration and braking, it manage to regulate the wheelbase lengthCheapSimple designskid pillar suspension systemThis kind of suspension features are almost the same as the independent rear suspension. And to be precise, it works as well as the current suspension system such as the wishbone suspension system and trailing link suspension system. But this technology is long gone in the 1950s and being replaced by wishbone.Sub-frame mounting suspension systemIn modern cars, reducing noise, vibration and harshness are important to the users. And in conventional suspension system, suspension systems are mounted to the chassis. In this suspension, it uses a sub-frame mounting to overcome the noise, vibration and harshness from the conventional suspension system. Its made out of aluminium to reduce the excessive weight.Rubber Suspension SystemThe reason why rubber suspension is being introduced is because it can store more energy per mass than any conventional type of suspension. The rubber springs works during compression, meaning to say that it replaces coil spring.similitude traction beam suspension systemCommonly known as a TTB. It is an independent suspension used by 44. It was first key out by Ford in the 1950s. This kind of suspension has an axle thats able to break into two suspension members. This suspension is being used to minimize the camber an d track change. When one of the wheels camber changes, the other follows but in an opposite direction.AdvantageDisadvantageThe suspension travel distanceCamber becomes negative a lot when in cornersStabilityReducing body rollDesignShock AbsorberIn the automotive world, there are 2 kind of basic shock absorber design that is still in use today. They areTwin organ pipe designGas Charged Twin resistance note Sensitive curb (PSD) Twin underpassAcceleration Sensitive Damping (ASD) Twin pipageMono-Tube designAir shock absorber damp shock absorberTwin Tube dampLow Pressure Gas Filled Twin Tube dampHigh Pressure Gas Filled Mono Tube DamperLinear DamperBefore I explain further the difference between these two shock absorbers, I would like to explain the basics of the shock absorber. Many people dont really know, or even care about the importance of the shock absorber. The main role of a shock absorber, in general, is to reduce as much movement of the suspension and the spring control as minimum as possible. To accomplish this, the hydraulic melted helps to remove all these energy through thermal, or heat energy. The construction of a shock absorber is often like an oil pumps. The piston is used to push the hydraulic fluid into the pressure render with the dish up of a piston rod. The hydraulic fluid is being forced to go through tiny orifices into the piston as the suspension is at motion, which is up and down. The resistance of a shock absorber varies, depending on how fast and the size of the orifices being pushed through the piston. Modern shock absorber can reduce the amount of bounce, roll, brake dive and acceleration squat because of the velocity sensitive hydraulic dampening being installed into the shock absorber. In other words, the faster the suspension movement, the higher the resistance of the shock absorber being provided. When the shock absorber is in motion, its moving up and down. When it moves up and down, it means the shock absorber is do ing a compression cycle and address cycle. Lets take a closer carry at the compression and extension cycle.Compression bicycleIn order for the fluid to move from sleeping accommodation A to chamber B, it has to go through 3 valve stages in the compression valve. When the piston is in a slow motion, the piston pushes the fluid flows through the oil port but with a restricted amount of fluid being flown to the oil port in order for both chambers to be controlled. But when the piston are moving in a fast motion, the opening of the disc from the valve seat are open widely in the camber B and causes the increase of fluid pressure below the piston. Theres restriction in the third stage orifice when the vehicle are at high speed.Extension CycleThe extension cycle happens where the piston and the rod are being pushed upwards. When the piston are moving upwards, the pressure in the chamber A will be higher than the pressure in the chamber B and thus the fluid are being flown into chamber B by going through 3-stage extension valve. The fluid volume in chamber A is insufficient t fill into the chamber B because the piston rod are being withdrawn from chamber B and this causes the pressure in the make tube are greater than the pressure in chamber B, causing the compression valve to be unseated.Twin Tube DesignLets take a look at the Twin Tube design. This kind of shock absorber has 2 tubes, one is known as the working pressure or pressure tube, and the other tube is known as the restrain tube. As you can see the picture on the left, the outer tube is used to store excessive fluid when the shock absorber is moving upwards and downwards. When the pressure tube is short of fluid, the reserve tube sends fluid to the pressure tube. During compression, the fluid in the pressure tube sends fluid to the reserve tube. The upper mount of the shock absorber are usually being connected to the vehicles chassis. There are all sorts of rubber being used in between the shock absorbe r and the chassis in order to reduce road noise and vibration being transmitted to the cockpit. The rubber bushings are flexible, so therefore the suspension can move freely. In the picture, you can see that the upper mount is also known as the piston rod, and the bottom of it is a piston. The piston rod needs to be guided when its at motion, so the engineers use a rod guide some call it bushing, to keep the piston and the piston rod straight. The seal are being used to keep the fluid and the pressure inside the shock absorber. At the base of the shock absorber, theres a base valve, normally known as a compression valve. This distributor point helps to control the fluid movement when the shock absorber is at motion. The design / bore size of the piston varies, depending on what application. Most 44 are using bigger bore size than the sedan cars. And because of the large piston diameter, the unit will become larger and the potential control will be higher. With bigger diameter, the operational temperature and the pressure is low due to area of the shock absorber and the piston bore and thus, this provides higher damping capabilities than the smaller bore.There are a few types of twin tube shock absorberGas Charged Twin Tube shock absorberPosition Sensitive Damping (PSD) Twin Tube shock absorberAcceleration Sensitive Damping (ASD) Twin Tube shockerGas Charged Twin Tube Shock AbsorberThis kind of suspension system uses low pressured nitrogen waste in the reserve tube but the amount of nitrogen botch up varies, depending on the amount of fluid inside the reserve tube. The purpose of the gas is to minimize the hydraulic fluid aeration to prevent the spark build up because foam can be compressed. The gas charged shock absorber provides engineers more flexibility to design the valve. The other main advantage is that in the vehicle, it creates a mild boost of spring rate. Among the other benefits of this shock absorber isThe reduction of roll , sway and dive, th e handling is improvedProviding better smooth control in any road conditions and cornersLonger heat transfer in gas charged shock absorberPosition Sensitive Damping (PSD) Twin Tube Shock AbsorberThe Position Sensitive Charged is still new in the automotive world. In this design, the ride control and comfort are optimized, thanks to the tapered grooves located at the pressure tube. This absorber provides a smooth and a comfortable by reducing the resistance onto the piston, by allowing the fluid to pass freely and smooth around the piston. Here are the advantages of this shock absorberProviding a smooth rideCan easily adapt to variable road and weight conditions.Acceleration Sensitive Damping (ASD) Twin Tube ShockerThe features of this absorber is the same as the other twin tube shock absorber, the only addition is that the compression valve is design to sense a bump on the road and automatically adjust the shock to provide better control of the shock absorbed.Mono-Tube DesignIn the mono-tube design, theres only one tube in the high-pressure gas shocks, known as the pressure tube. There are two working piston inside the mono-tube design, that is a working piston and a dividing piston. The mono-tube and the twin tube design are almost similar but the only difference is that the mono-tube can be install in any way, either mounted height down or right side up, but either way, it still works the same. The unique design of the shocks is that it doesnt use a base valve, but it uses a piston to control the extensions and compressions. In the mono-tube design, it has a larger pressure tube to comply with the dead length, compared with the twin tube design. The downside of this design is that its going to be hard-fought for the engineers to install this kind of shocks into the cars instead with the twin tube design. The separation of the gas and the oil is done, with the help of the free-floating dividing piston. The gas below the dividing piston is pressurized, at ar ound 360 psi to accommodate the vehicles weight. When the shocks are at motion, the movement of the dividing piston varies, depending on the movement of the piston rod in order for the pressure in the tube are pressurized at all times. Heres the upside of the designCan be mounted freely, compare to the twin tube design, and helping to reduce the unnecessary unsprung weightThe working tube can work harder because the working tube is exposed, so therefore can be cooled easily.Every upside of the design, theres always a downsideEasily unmake when theres a dentHard to install onto the passengers car that has a twin tube designDamper Shock AbsorberDamper shock absorber, or as short, damper, are used to provide an optimum absorption of shocks and smooth lateral deceleration. The dampers can be powered by fluid, or mechanically powered.