Yellowed pages of a magazine in 1969 demonstrate undoubtedly progressive development of those years in the field of passive safety. Development of power structure of the body in the form of arcs, concluded in a roof rack. Traumatic special upholstery and interior camera instead of mirrors. Fuel tank separated from the passenger compartment sealed bulkhead and the fire suppression system in the engine compartment.
The apotheosis of technical thought late 70s perceived front bumper by hydrosupport capable of absorbing impact energy. In general, a kind of analogue current SRS – Supplementary Restraint System – passive safety systems. However, without the usual attributes like today belts with pre-tensioners and airbags.
Yes, the security perceptions were then very peculiar. However, as customers, artists, as well as the reaction from the public and politicians. For example, the above solutions was punctuated with a pathetic car called New York. Developed its aviation company Republic aviation, famous fighters of the Second World War and the Vietnam War. Customer in 1962 acted NHTSA – American Committee on safety on the roads. The car did not go into a series, moreover, likely to be only in layouts. And in 1970, the same organization tried to oblige all motor companies three years to equip their models with airbags. At a normal level technologically to accomplish this was impossible. Disclaimer producers supported the media and politicians.As a result, the mandatory use of pillows introduced only 20 years later.
Apparently, New York car was not realized even in the form of a full-size layout. In any case, reliable information about the no. But there is a description and schemes that eloquently – in the late 60-ies future SRS was in its infancy
In the 70s the company bought the Republic Aviation and its airline Fairchild still created two prototype called ESV, which were broken in the frontal crash test of the rigid barrier at a speed of 50 miles / hour. Standard car is not produced
The rating system
It is significant that now is the American method of crash-test the most advanced and robust. In mid-2012, the American Insurance Institute IIHS conducted the first series of tests by the following rules: 64 km / h, and 25% overlap rigid barrier. In this case, the impact has a wheel, possibly by the spar and the more other deformable zones front of the car. Perceives the entire load cell power salon. As a result, almost failed the test cars like Mercedes-Benz C-Class, Lexus IS 250/350, Acura TSX, Audi A4, Volkswagen CC, Lincoln MKZ, Lexus ES 350, BMW 3 Series and the Toyota Camry.That is, those in which good security on the basis of tests Euro NCAP no doubt.
Crash Test Lexus IS 250/350 with a 25% overlap m
But in the mid 90s of last century, the situation was much worse. State standards do not exist. Full-scale safety tests carried out only the most wealthy manufacturers. Only in 1996 succeeded in forcing law firms to fulfill the norms of the UNECE number 94: 56 km / h, 40% overlap and impact on crushes barrier. Just one year independent European Committee (Euro NCAP – The European New Car Assessment Programme) conducted a series of crash tests by the same rules, but at the speed of 64 km / h Despite the fact that the rate of collisions rose by less than 15%, the kinetic energy of impact has increased by more than 30%. Curiously, Euro NCAP tests still are not state status (officially exist to the same standards number 94), although sponsored by a number of countries. And yet they – the starting point in the development of all civilized car manufacturers. It just so happens (and rather quickly) that without the normal rating from Euro NCAP make way to the European market ordered. This happened, for example, with the Chinese, which surprised like civilized Old World consumer attitudes towards their products.
Crash test Audi A4 last generation procedure Euro NCAP. Five stars or 93% protection of the front passengers. Interior dimensions have not changed, the door opens without effort, the driver and passengers good protection of all body parts
Crash test Audi A4 procedure IIHS – the same 64 km / h, but the rigid barrier and 25% overlap. Broken superstructure cabin door is jammed, torn wheel arch. Overall protection in a frontal impact assessed as weak
Modernization of the skeleton
What has changed during the “reforms” in the field of passive safety? First of all, the power structure of the body. This is clearly seen in the photographs and reports, comparing models of the late 90′s and cars that appeared 10-12 years later. Differences – striking! At first almost all cases crumpled front roof rack located behind the “shock” wheel, or even the roof. The driver’s door was open sometimes, in some episodes, in contrast, is dented and locked. Steering “entrance” to the salon, there is a floor area served under the pedals. On some machines the driver swipes on the wheel head and breast. Almost always a risk of contact with the front panel exposed knees, shins and feet of the driver. The worst situation – the gap wheel arches and niches for the driver’s feet.
Between the Peugeot 306 (top) of 1993 and its successor index 307 (bottom) of 2000 model year, passed through crash tests by the method of Euro NCAP, a huge difference. In the first case, attention is drawn to the crumpled roof rack and door. The driver turned out to be poorly protected chest and left leg could get damaged on the front panel. When you create a 307-th French recognized this – much better protects car sitting inside, including a side impact
Now even less of it – is reason to doubt the success of the model on the market. When suspensions, often wandering from generation to generation, are much tougher stretchers. A power structure of bodies over the past decade and a half seriously evolved. It’s not about carbon fiber monocoque other sports cars. Or about aluminum, which is due to the extensive use of new technologies connection details, such as their bonding. In the end, it is the prerogative of the most expensive cars. Such is not surprising even the use of ultra-light magnesium alloys, although more recently this controversial automotive metal used mainly in sports. New materials have come to the democratic classes, starting with golf segment. With each new generation of the share durable and high-strength steels, which now can be up to 50-80%. Spars are made from it, sills, tunnel floor, roof racks, bumpers amplifiers. In other cases – motor shield floor, the rear wheel arches. As a consequence, the torsional rigidity of the body has increased to 30,000 Nm / deg, sometimes up to 40,000 Nm / degree, that is one and a half to two times. A computer simulation allowed before the Incarnation in metal deformation front calculate the correct power components.
The superstructure of the modern car is half of high-strength steels. But, for example, Volkswagen uses up to 80% of such materials. Of these, almost all made a “skeleton”, including some small details
Progress has affected even this conservative transport, as pickups. Conduct their crash tests Euro NCAP beginning in 2008. Then repeat the situation of 1997 in respect of cars. Only adjusted for frame construction, which gives little opportunity to implement collapsible zones. Most of the subjects received one or two stars. Only Mitsubishi L200, which appeared in 2006, won four. But, for example, the latest innovation in the classroom – Ford Ranger – have earned five stars. The design of the cabin “Ranger” is also used high-strength steel, which made sills and roof rack. The main hit take on the frame side members are now able to properly absorb energy. To the detriment of ordinary strength. Knowingly repairers note – frame pickups, SUVs and generally released in the past few years, is not so kondovye as before. Restore them much harder, if this is possible in principle.
The results of the crash test Nissan Navara were very sad. Spar frame with “shock” side vmyali the floor pedals significantly shifted back, seat belt pretensioners and airbags worked at the wrong time. The driver and passenger experienced high load on the head and chest. The latter also has the risk of impact damage to the cervical vertebrae. Both dummies feet firmly in contact with the front panel. As a result, only one star, and then crossed
Ford Ranger has proved that the pickup can be “five star.” Good distribution of kinetic energy, the whole cabin, excellent occupant protection
Tighten the belts!
In contrast to the power structure of the body, which is under the psychological influence of the crash test Euro NCAP changing rapidly past decade and a half, one of the visible elements of passive safety was far more a long way. First prototypes of belts appeared in the late XIX century, they were offered for coachmen. Since the beginning of XX century belts then began to acquire rare cars. Yes and no straps at all – so lap. These, incidentally, lasted rear to 80s. The front also changed its structure to the current three-point in 1957. After a couple of years from Sweden and Volvo began a gradual transition to them in other countries and other major automakers.
Nothing more progressive yet been invented. Moreover, to his present form belts evolved gradually. For example, only in 1972 was designed inertial tension mechanism that defines the freedom of movement in normal conditions, but when a sudden stop blocking the belt. Thanks to him, managed to dramatically reduce the risk of injury of the abdomen and chest, as well as eliminate the possibility of “diving” man under the strap.
Further improvement of the inertial belt was the appearance in 1987 of the pretensioner. Previous mechanism restricts the movement only upon collision. Pretensioner is activated for the first time of impact and the fact that “tighten belts tighter,” he has a “whole” 250-300 milliseconds – so many “lasts” himself contact with an obstacle. But everything is 20-25 times faster – a device to prepare the driver and passengers to meet with pillows. There are different options pretensioners – ball, rack, rotary, cable. They are united by two pitfalls. In all the main working tool acts squib.And does anyone have force limiters, which allows to avoid the critical loads on the human body: lower a little belt or having variants of its elongation.
Lap like that used in aircraft, used in the front seats of cars before the end of the 50s. A rear lasted 30 years, mainly in the United States
Not softer, but more
And at the time of action, and inherently airbags – the last redoubt of defense sitting inside people. The need for something like that aircraft designers realized back in the 40s. However, on the cushion for car thinking until the end of the 60s, when the U.S. authorities and the public, it became clear – the death rate on the roads is comparable to losses in the fighting. Availability of safety systems in vehicles approved legislation even remembered about the idea of pillows, which in 1953 offered two engineers simultaneously on opposite sides of the ocean. And about a key, as it later turned out, the element system – a ball sensor (invented in 1967), are required to report sharp deceleration. Abolition of this initiative quickly lobbied. But do not forget about the developments. In varying degrees, pillows interested in Ford, Chrysler, GM. The latter group in 1972 Oldsmobile Toronado even appeared with air bag for a fee. But this option is not popular became. But with the Mercedes-Benz 500SEL sample of 1983 it went faster. From 1993-94 all major manufacturers have started to equip their cars at least a driver’s airbag, and in many cases the passenger. Then there were the side inflatable elements later blinds.
Fundamentally since its appearance circuit triggering the airbags did not change. Moment of collision fixed acceleration sensors (formerly ball, mechanical, electronic now), which under the influence of inertial forces, roughly speaking, are closing. Signal is sent to the squib, and he, in turn, inflate the pillow. On the way from invention to mass consumption solved primarily two technological issue – the material itself pillows and fuel squib.In the first case settled on a half millimeter thick nylon, inside coated with rubber for tightness. It is this “fabric” in deployment speed cushions in the 250-300 km / h was optimal for the risk of injury. But in fuel quality after a number of failures have chosen sodium azide, which is converted during combustion into nitrogen and carbon dioxide. The first is not a danger, in the second cavity filter pillows do not miss.
These elements, as immutable, were taken before the era of indiscriminate crash tests, especially under the auspices of Euro NCAP. More recently, the experts are working on the very process of opening pillows. Change the total time (from 20 to 30 milliseconds), make it gradual, in order to mitigate the appointment of the head with a dome. Adjust the interval between stages, tying the second stage of opening to the force of impact.Newly emerging systems are able to take into account the weight and dimensions of people, as well as the distance to the installation face pillows.There are options for the front passenger air bag, which primarily take on the shoulders and chest, and then his head. We are working in order to relieve the shock from the abdominal cavity. Nobody is surprised cushion for the driver’s knees. On some models, side airbags and curtain can not deflate to 10 seconds, providing a safety tip-over. On the new S-Class rear passengers are protected “Air begom” built into the strap with a small pillow under your knees to protect them from slipping under the straps. A Volvo V40 CC was the first car that protects pedestrians not only raise the hood, but also an inflatable “mattress”, covers the bottom of the windshield and roof rack.
Volume driver’s airbag is in the range of 60-80 liters. Passenger air bag reaches a volume of 130 liters. Now, however, manufacturers increase the size of pillows and change their shape to receive first the shoulders and chest, and then head
The distance between the rear passengers and backs of the front seats is large enough. Therefore, to protect the people, now began to use pillows, built-in seat belts
Volvo V40 and V40 Cross Country was the first pedestrian airbag. Hiding it from the windshield and fires only after the jump thanks to squib rear edge of the bonnet
The Russian Case
In Europe, six airbags, including curtain, became standard equipment on even some representatives of segment B, not to mention the golf class. Our situation is different. Until we are willing to pay for safety and the manufacturers know it. The best that can expect Russian consumers C-Class – two front airbags, sometimes even one. The rest are offered either in the upper framings, or for a fee under the relevant packages.
And when buying a car from the category of second hand on the functioning of the entire system, the presence of pillows few people pay attention.Although at least the data should be in the service books, if they are available. Or, as a maximum, determined elementary diagnostics. Of course, the cost of a full recovery SRS will not be cheap. For example, the price of each of the front airbags depending on make and model is in the range 7000-12000 rubles. Sensors, which (including side) can gain up to ten, estimated at 2500-6000 rubles. However, there is the question arises whether it is necessary to repair the car – under such damages. But after a little accident SRS can “revive” good for the price “music” from the dealer or even cheaper.
Skoda Rapid, which should appear in Russia in April of this year, for the European market already in the “base” has front and side airbags as well as curtain. But we even flagship Superb as standard equipment has only two “Air begami.” The same situation with other new models offered in our market. Full security package can only rely on D or E classes
On the disadvantages of the complex, which is called passive safety, talk like is not necessary. Naturally, it is not free. Funds invested in it raises the cost of the car. But, for example, the same can be said about the various media, computer, some service functions are often not directly related to the management of any car or his comfort, even more so with safety. After selection, if so put the question in favor of airbags, ESP and other systems is obvious, is not it? And that principle, vehicle safety, quality and quantity of electronic assistants, which he punctuated with, does not affect the reliability and life of its units. Is that body repair is not always financially expedient and certainly not capable of “authentic” to recreate the old power structure. Quite adequate payment for the preservation of health and life.
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