Continuing the theme of manageability and security of the car on the road can not mention this to the major structural component, as a suspension. Certainly, the machine's behavior affects almost everything - weight distribution of the axes, body rigidity, rubber and, of course, well-designed suspension. Experts say that the most adequate to the car's behavior affects it back design and suspension. Well-known automakers are fighting over the right settings, because often puzzles that throws their lives and buyers have the opposite decision. Handling and comfort, for example. Consumers do not want to travel on horseback to the breakers, but there is a desire to have a clear, predictable and, most importantly, safe reaction at the active driving. Desires are mutually exclusive, because the softer and more comfortable car than the higher profile tires, the greater the slip, worse adhesion to the asphalt, and as a result of an early and perhaps unpredictable departure from the desired trajectory. Comes to the aid of electronics, there are stabilizing system of the new generation that will not only slow down your right wheel, but also control the "thrust vector", setting a specific wheel additional torque. Such systems are already in full use, for example, Honda Legend and the new BMW's X6. One aim - to prevent dangerous behavior, and if bezshabashny driver too overdone at the rate of rotation, it is desirable not to develop a skid. Tendency to oversteer, that is, to skid the rear axle, it is considered unacceptable for civilian car. Respectively, and electronics, and podvesochniki in tandem trying to achieve from their offspring understeer in extreme conditions - that is, if the car is already "bear", then at least let "is" correctly. Understeer can save at least some control over the car, even a relatively inexperienced driver while out in the wild without the loss of the skid can not every professional. City streets do not rally tracks, passing and oncoming traffic has not been canceled. If the order, suspension performs several functions - direct (kinematics), smooths out the road profile (work elastic elements - springs, torsion bars, springs, etc.), eliminates vibrations, does not develop resonance (shock absorbers). However, some time ago there were pneumatic counters that perform tasks and springs and shock absorbers. Decision effective but expensive. Of the domestic market segment is often such a scheme applied Subaru, well, premium brands are willing to use such solutions - Mercedes, Audi, Land Rover, etc. The most important task for directing mechanism - save a permanent rut. It is interesting that here in different modes of movement are optimal variety of schemes. For example, that on a flat road is best keeps track? Continuous Bridge. Wheels nowhere to go, the body roll or not, the track is preserved. On the road irregularities the situation is the opposite. Of continuous rear beam, playing about the body (at running one wheel on the mound, for example), will considerably change the track. The wheels start to slip across the direction of motion, and there will come a sharp drift or drift. With this you can fight. Sample design of the rear of a continuous bridge is called De Dion and applied, in particular, on some models of Alfa Romeo. Complicated system of levers of the parallelogram Watt, with "drawbar" showed an almost perfect handling on the road with any coating, but it should be noted that the machines Alfa Romeo never been famous for not cheap, nor reliable. The question arises - is it worth fuss? Perhaps there is a simpler but no less effective engineering solutions? The best scheme suspension for a race car is known for a long time - double wishbones, upper shorter, lower longer. In any case track is changed slightly, the remaining conditions, which will be discussed below, are also satisfied. But the price! Such a suspension - not a cheap, but if you say "A", should be continued and further down the alphabet. Reduce unsprung mass using levers of aluminum. Brakes can be taken to the main transmission for the same purpose, to add the differential with electronic control, etc. As a result, buyers are beginning to feel sad, seeing the price tag of this car in the showroom. Unfortunately, not only the ability to keep track of vehicle suspension is required. Many conditions, and the next one - the rear wheels when the suspension moves should not taxi up, or rather can, but only in the right direction. Remember thruster Multilink, applies to the Volvo, and Mitsubishi, and BMW, and MB. Almost all large firms have used or are using Multilink still por.Otlichnaya design, but is expensive and does not like bad roads (not in the sense that it is bad for him coming, and quickly wears out). Another problem - the "game" suspension to abrupt acceleration and deceleration. Kinematics should not significantly change under the influence of external and internal factors, despite the compression and deformation of silent blocks. Here everyone is fighting their own way. Toyota, for example, instead of rubber-metal hinges of the rear just uses metal hinges (GCs) in the independent suspension of the zheCamry, and if I'm not mistaken, already in 1996 This design came from racing, and exemplary Japanese technology made it affordable. But that's not all. Wheel turns should not break under a body, and best of all - lean into the turn. The best results here shows again the circuit in double wishbone wishbone, although torsion beam (associated trailing arms) behaves quite well. Well, the last condition - the unsprung masses must be small, except in the case of very hard springs and shock absorbers of the productive machine will be very bumpy. But if the suspension and comfortable, and unsprung masses are large, in a bad way this car will spend most of their time in the air, ie, become almost unmanageable. And then manufacturers use off-budget moves - arms of aluminum, hollow forging, forged wheels, etc. In other words, reduce the weight as soon as they can. The most popular current diagram of the rear suspension - torsion beam, working on twisting. The scheme is simple, inexpensive and efficient enough. There is here, of course, and the minuses that podvesochniki eliminate their own way - put additional leverage and traction. Added traction Panara, for example. A favorite scheme nissanovtsev - beam with a Scott-Russell mechanism. Now torsion beam is the most used scheme for low-cost cars. The rear axle of the new Jeep Cherokee overgrown with many rods designed to neutralize the old design with the uncut rear axle, in addition, still leading. Expensive cars, especially the premium segment, closer approach to racing standards: double wishbones, or very close to the kinematics of the scheme - the new Infiniti FX, G37S, BMW Z4. In general, each type of modern suspension has a right to exist, especially if it worked with the manufacturers name. In any design has its own peculiarities. Other things being equal, independent suspension a little bit softer and more comfortable, usually a little better behaved in the bends. But then again, not always. When buying a car, especially when the six-digit sum is, of course, have a desire to fully evaluate the car just for yourself: fit - does not fit. Ride at a speed of 10 km / h around the showroom is unlikely to make a choice. But already there is some progress - automakers, possibly frightened by the financial crisis, now give an opportunity to assess their offspring - Audi quattro camp in Yakhroma, Land Rover Experience - Polygon Land Rover in the same territories. I hope to join such an undertaking and the other members of the Russian automotive market.
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