In Russia, now you can, if not everything, then a lot. For example, from now on it is allowed to produce cars without ABS and ESP – in order to reduce the dependence of domestic manufacturers on imported components. Maybe we don’t need these foreign three-letter letters?
IThus, with the entry into force of Decree of the Government of the Russian Federation No. 855 “On approval of the application of mandatory requirements for certain wheeled vehicles and the assessment of their compliance”, Russia, in terms of the level of technical requirements for preventive safety systems for passenger cars, found itself in approximately the same conditions as underdeveloped African countries. There, too, it is allowed to produce and sell cars both without a stabilization system and without ABS. But our country is not Africa – and we have plenty of slippery roads. The benefits for automakers are clear. And how does all this threaten ordinary people, that is, you and me?
Let’s start by refreshing our memory of what ABS is.
Even a simple ABS requires an electronic control unit mounted in one housing with a hydraulic unit (1), and four wheel speed sensors (2). But the steering angle sensor (3), the unit for measuring accelerations and angular velocity around the vertical axis (4) is already an add-on of the stabilization system, which is also tied to the engine control unit, aka ECU (5)
The system calculates the so-called reference speed using speed sensors for each wheel. If, during braking, the speed of rotation of one or more wheels turns out to be significantly lower than the reference one, this is a signal for action: the ABS, using an electromagnetic valve, closes the brake line serving the sharply slowed down wheel, and if this is not enough, it opens another solenoid valve, dumping excess pressure into the compensation chamber. Brake pads loosen their grip, wheel slip decreases. And then the valves reconnect the line to the pressure, which is created by the driver’s right leg with the help of a vacuum brake booster. And if the pressure is too high, the cycle repeats over and over again.
That is how, intermittently, on a slippery road, an experienced driver slows down in a car without ABS. Electronics does this at a frequency inaccessible to humans – up to 20 times per second! – and accuracy. Moreover, it has at its disposal not one brake pedal, but actually four: a modern four-channel ABS brakes and releases each wheel individually.
Properly tuned ABS not only minimizes slip on uneven surfaces, the so-called “mixed” (wet basalt under the right wheels of the Defender in the photo is like ice), but also reduces the braking distance. Even an experienced driver who alternates between brake application and precise steering correction will not be able to outperform the ABS in these conditions.
We have many times (not only in AR №6, 2013) mentioned the shortcomings specific to anti-lock braking systems, and drew the attention of manufacturers to flaws in the electronics algorithms (suffice it to recall the story of the Volkswagen Polo sedan). But the facts are this: even an imperfect ABS helps the driver maintain at least some control over the car during an emergency deceleration and allows you to operate the steering wheel in an emergency. On a car with locked wheels, this is simply impossible – it moves where the force of inertia directed it at the moment when the driver slammed on the brakes in a panic.
And there are spots on the sun – there can be misses in the ABS algorithms. Everyone has heard stories about Kaluga Polo and Tiguan of the first generations, but special tests developed in Autoreview made it possible to identify shortcomings in the ABS of dozens of cars
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