The EBD (Electronic brake distribution) system is a logical continuation of the anti-lock braking system, which increases the range of braking correction and corrects the shortcomings of the more archaic ABS.

The development of the system was carried out back in the 80s of the last century, but the mechanism has received mass distribution only today. To understand what EBD is, you need to remember the basics of the anti-lock braking system.

What is ABS and what are its disadvantages?

ABS is a mechanism that prevents the brakes from locking up and maintains control during emergency braking. Contrary to popular belief, electronics do not shorten the braking distance, but even lengthen it on bare ice.

The essence of the ABS action is that the electronic unit, receiving blocking information from the sensors, forcibly releases the braking force for a short time, allowing the wheels to “catch” the road again for a split second. In a second, the electronics perform up to 25 cycles of braking - force relief.

ABS only works during emergency braking. In addition, when one of the wheels is blocked, the anti-lock mechanism relieves pressure in both brake circuits. The braking force is equal on all chassis. This leads to a lengthening of the braking distance, a discrepancy between the intensity of braking of the front and rear circuits, and increases the risk of the car falling into a skid.

How EBD works

What is it - ebd in a car? The brake force distribution system is not a replacement for ABS, but its more advanced version, an addition.

The electronic block of the distribution mechanism from the sensors installed on each of the hubs receives information about:

• wheel speed;
• speed;
• workload;
• road grip level.

It is important that the information is individual for each disk. Here lies the fundamental difference between the EBD brake force distribution system and the classic anti-lock mechanism, which relieves pressure in the brakes when even one wheel is blocked.

The brake force distribution system works only with those wheels that are locked. This is important in situations where one pair of wheels is on a snowy roadside, the second is on asphalt.

The second fundamental difference is the fact that ABS EBD works not only with full, but also with partial pressure on the brake pedal. As a rule, inexperienced or overly cautious drivers make a similar mistake on cars where an electronic braking correction system is installed.

The third difference that distinguishes EBD from classic ABS is the ability to brake in long turns. At the same time, efforts are distributed in such a way that the car does not break into a skid. Similar actions with or without classic ABS will lead to a breakdown of the rear axle.

Disadvantages of EBD

The EBD brake force distribution system has certain disadvantages. However, all of them are not independent moments, but uncorrected problems of its predecessor - the classic ABS. The main problem associated with the operation of anti-lock braking systems is considered to be the lengthening of the braking distance when driving on winter studded tires.

The fact is that studded tires with blocked brakes play the role of a kind of anchor. They “bite” into the ice crust, creating tremendous slip resistance. Thanks to this, the car stops quickly enough even in ice. This does not happen when EBD or ABS is running.

By depressurizing the brake circuits, the electronics allow the wheels to constantly roll without catching on the road. This lengthens the braking distance by at least 10-15%, which has been experimentally proven more than once (Za Rulem magazine, December 2001).

The distribution of braking forces under electronic control has one more drawback, rather conditional. The fact is that a car equipped with an EBD system is not suitable for sports driving.

It's virtually impossible to achieve the controlled skid so favored by street racers. The driver cannot drive the car as he sees fit. However, this is true only for experienced racing drivers and people involved in extreme driving.

As a conclusion

EBD is an excellent electronic assistant that can make life easier for a novice driver and insure him against braking errors.

At the same time, you cannot completely rely on the operation of electronics. On ice and slush, a car equipped with a brake force distribution system can behave unpredictably.

When reviewing the modern car market and buyers, the question arises, what is EBD in a car and what function does a system with this abbreviation perform. The abbreviation EBD stands for Electronic brake-force distribution (in German EBV models - Elektronishe Bremskraftverteilung) - this is a brake force distribution system that is a software addition to the traction control system (ABS) familiar to many motorists.

Unlike pure ABS, ABS + EBD controls the behavior of the car in all driving modes, including emergency braking. It is important to understand that EBD is not a mechanism, but a specially designed software, a kind of ABS action controller. Leading car manufacturers have been installing the EBD system on cars (not only cars, but also motorcycles and heavy trucks) since the early 90s, when it was noticed that the classic anti-lock braking systems installed on new models often do not cope with their tasks and perform incorrect actions. which can lead to disastrous consequences.

Illustration of brake force distribution using EBD (Electronic brake-force distribution)

EBD is a system that, by distributing brake forces to different wheels, helps the driver to keep the car on the desired path. When cornering, the system does not allow the machine to skid or dangerously change the trajectory of movement (stall). Another task of the EBD is to regulate the behavior of the anti-lock braking system on mixed roads, optimize its effect and prevent excessive or insufficient electronic intervention in the control process.

Here are some examples of when an EBD system can be useful:

• During emergency braking.
• When braking on mixed surfaces. For example, when driving on one side of the car to the side of the road or an area with a surface other than the road.
• When braking when turning - the distribution of the load on the brakes to maintain the balance of the car.

How EBD works

Electronics, using sensors, determines the change in the speed of rotation of a particular wheel or pair of wheels, which occurs when the car hits a difficult surface, for example, an area with ice or water. By analyzing data from sensors, the EBD system determines the degree of adhesion to the roadway of each of the wheels and decides on the distribution of braking force. After that, the valves receive a command to increase or decrease the work of the brake discs. After balancing the braking forces, the EBD stops working and allows the driver to freely maneuver and change the trajectory of movement.

Video about EBD

Benefits and contribution to safety

The EBD system has no pronounced disadvantages, and experts note a number of advantages in its use:

• the optimal choice of the coefficient of adhesion with the road of the rear wheels under any road conditions;
• control and improvement of the work of ABS, increasing the stability of the car;
• reducing the degree of wear of brake pads and discs, increasing their service life, compliance with temperature operating conditions;
• reduction in the required effort when the driver presses the brake pedal.

The UN International Traffic Safety Committee noted the invaluable contribution of the EBD to the work to ensure road safety and preserve the health and life of motorists, passengers and pedestrians.

A modern car is literally crammed with various stabilization and safety systems. The principle of their work is such that it is simply impossible to do without a staggering number of electronic filling for their proper functioning. The topic of today's article is the EBD brake force distribution system. We will talk about the benefits of the principle of operation that the system has, and give an exhaustive answer to the question of how it works.

Main advantages

The EBD system is a fairly new technology, if, of course, we compare it with the classic ABS system that has been installed on production cars for the past three decades. EBD appeared in the early 90s, and for the first time it was used on foreign-made cars.

The appearance of such a system was prescribed by those who ensured traffic safety on public roads. After analyzing the statistics, the engineers found that the ABS does not solve the problem of skid prevention, and the reduction in braking distance does not always occur.

This is what required the development of a brake force distribution system that would solve most of the problems that the driver has during the next emergency braking.

What are these problems? The fact is that when the car starts to brake sharply, a load of different force is placed on its wheels. In this case, even in a car equipped with ABS, the braking force on all four wheels will be the same.

But do not forget that different loads fell on the wheels. This will cause one axle to slip, while the other, which has slightly higher traction, will already be blocked. This will shift the drag force that is being applied to the car and the car will eventually spin. It is not necessary to remind once again that this threatens with an accident and loss of control, which is especially important when driving on slippery surfaces, whether it is ice or wet asphalt.

The EBV system is designed to distribute braking forces in a strictly defined way. Their distribution occurs so that the wheels that are least traction will receive the least braking force, which will lead to the absence of blocking and subsequent skidding.

The wheels that have the best grip on the asphalt will brake with more force. Ultimately, this will cause all four wheels to brake equally. Due to this, the safety of the driver and passengers will increase many times over, and braking will be more comfortable and predictable.

detailed look

The principle of operation of such a system is quite simple. The entire functional unit consists of only three blocks, which are connected to each other in series and operate synchronously. So, without fail, special valves are installed on the machine, which can be adjusted using a servo drive or hydraulically. The principle of operation of these valves is such that when an electrical impulse is applied, they can open or close in a certain way, regulating the pressure of the brake fluid.

The opening of the valves is controlled by the control unit, the principle of which is based on the use of the board and the software embedded in it. The unit receives signals from sensors that are connected to the wheel hubs and evaluate the speed of their rotation at the moment when the brake pedal was pressed.

Due to this, the system works constantly, because the control unit and sensors become active exactly at the moment when the driver starts the engine. This ensures that the driver and passengers are always safe, and braking does not become an unpleasant surprise that can lead to an accident.

Summary

The brake force distribution system is a powerful tool that greatly increases the safety of the driver and passengers. The use of such a system leads to the fact that the car becomes more predictable on the road, and braking does not turn into a dangerous skid, which can lead to sad consequences.

When you press the appropriate pedal, the brake mechanism is activated and the wheels begin to slow down rapidly. Such a scheme of brake operation is far from ideal, and in budget cars, the response is sharp and overly rapid, which causes inconvenience to the driver and reduces the safety of his movement. An excellent invention was the brake force distribution system. It raises many questions and still remains incomprehensible to car owners. We will correct this situation and figure out what EBD is in a car.

How EBD works

Already from the name it becomes clear that it is aimed at the competent distribution of braking force between all wheels. An example will make it easier to understand the scheme of work. Let's imagine a standard situation for every motorist - a ramp to the side of the road. In this case, a pair of right wheels end up on a dirt road, the characteristics of which differ significantly from the asphalt surface, even if not of very high quality. The left wheels remain on the pavement.

The characteristics of the movement of the car differ significantly depending on the type of road surface: friction force, grip level, different braking. If the car starts moving in the situation we have described, then it can be skidded with a high degree of probability. But only if the EBD brake force distribution system was not provided by the manufacturer. In more expensive and modern cars, this development will direct more braking force to the left wheels, and weaken the brake force on the right wheels. As a result, the driver will not lose possession of the car for a second and will keep the situation under control.

EBD work organization

In short, the electronic brake force distribution system is responsible for monitoring the situation on the road, reading the data received by the ABS unit, and distributing the force that is sent to each wheel unit.

Each wheel has sensors that send data to the ABS unit. Rotational speed, internal pressure and degree of adhesion are taken into account. The information is analyzed separately for each wheel, therefore, the calculation of the necessary distribution of the braking impulse is carried out for each wheel separately. allows you to achieve high accuracy in the operation of the system and minimize the likelihood of errors and errors.

Is everything so good in EBD

No electronic system is so perfect as to work without errors and have the ability to provide for all possible options. It may well happen that the electronic equipment of the car will incorrectly analyze the short-term decrease in adhesion, which is typical for Russian roads. In this case, electronic brake force distribution (EBD) will work more to harm than good.

The efficiency of this system is reduced. The usual braking process, without the use of smart electronics, will achieve a better result. This feature is explained by the presence of a deep tread on winter wheels, which in the locked position will themselves work to reduce the braking distance.

These shortcomings are more than offset by the advantages that are characteristic of EBD:

• rational distribution of braking force;
• individual calculation for each situation;
• assistance in maintaining the correct trajectory of movement;
• minimizes the likelihood of drifts and drifts;
• maintaining efficiency regardless of the type of braking.

Specialists do not stop working on improving the system we are considering, and, perhaps, very soon car owners will be able to use absolutely. In the meantime, let's be content with the existing electronic device for distributing the braking force.

The ABS system, which has such a good track record: does not allow the wheels to lock up, provides excellent handling and efficient braking on slippery road surfaces, also has significant disadvantages..

But it does not matter if another system is also installed on the car - EBD (Electronic Brake Force Distribution), which copes well with compensating for the shortcomings of ABS. So how does the brake force distribution system work and why is it needed?

What is ABS? And what are her shortcomings?

Anti-lock braking system per second can make 15 to 25 cycles braking. Even a mega professional in the field of extreme driving due to physical factors is not able to carry out more than 5 braking per second.

The task of the ABS is to convert the driver's constant pressure on the brake pedal into a periodic one, which allows you to maintain control over the car. That is, the main task of ABS is to maintain controllability.

Yes, ABS is a great defense against "fools" and a strong support for inexperienced beginners, but there are also disadvantages:

During system operation, it is difficult to calculate and predict when it will stop, because braking is not actually controlled by the driver;

There may be delays in turning on the ABS, because for it to work correctly, it must conduct a test of the road surface and calculate the tire adhesion coefficient with it. This is possible on slippery roads when driving at speeds over 130 km/h. This is important to know in order to be prepared and not get confused, thinking that the brakes have failed!

If there is a frequent alternation of uneven and uneven road surfaces, the system may not always respond correctly at what point and for which road to calculate the correct friction coefficient;

If the car jumped, the system suspends the braking force. This can lead to a sudden uncoordination of the driver at the time of inactivity of the ABS;

The anti-lock braking system eliminates even the smallest attempts to lock the wheels, which can cause discomfort on loose and loose surfaces;

ABS terminates its function at speeds up to 10 km/h. Yes, this is the norm for passenger cars, but if we take into account heavy vehicles, such as cash-in-transit or executive armored vehicles, then a distance of up to one and a half meters can be added to the braking distance, which can clearly lead to an accident.

How ABS works

ABS in the way it works is somewhat reminiscent of the behavior of an experienced driver behind the wheel of a car. For example, on an ice surface, when you need to intermittently slow down, keeping the wheels on the verge of blocking. In addition to all this, ABS aligns the work of the wheels, automatically adjusting the braking force. This happens at such a level that the car does not lose its directional stability.

The complexity of the technical execution does not apply to the principle of operation of this system. After the driver presses the brake pedal, the braking mechanisms of the wheels are affected by the brake fluid. At the point of contact of automobile wheels with the road surface, braking forces begin to arise. If you continue to press the pedal, the braking effect will certainly increase, but only up to a certain point. If you further increase the brake pressure, then positive results should not be expected, since the wheels simply block, their rotation stops, and the slip, on the contrary, increases, although the effect of the braking forces remains at the same level.

As a result, the car becomes almost impossible to drive. ABS does everything necessary to ensure that you simply avoid such a development of events. Having received signals from the sensors and comparing them as necessary, the ABS control unit commands the distribution valve to reduce the fluid pressure in the brake system, no matter how hard you press the brake pedal. Important in the principle of operation of ABS and the fact that the system individually determines the braking of each wheel, which began to experience blocking. When the situation has stabilized and the blocking probability has passed, the brake fluid pressure is normalized to prevent underbraking of the wheels.

Each driver needs to know the difference between driving a car that is equipped with ABS and a car without this system. When driving a car with ABS, feel free to press the brakes, the wheels will not lock. Sometimes for drivers who have moved from old cars to models equipped with ABS, the process of getting used to is not easy. After all, earlier it was necessary to “play” with the pedal, but now you just need to press the brake to the floor.

How EBD works

EBD monitors the control of the distribution of braking force to all wheels. It operates on the data provided by the ABS block. Each wheel of a vehicle fitted with an EBD system is equipped with sensors that transmit wheel speed by means of electrical signals. More system sensors read the pressure in each wheel, determining how much the car is loaded. In general, EBD has data on how fast the car is moving, how loaded it is and how good the contact of the wheels with a particular road surface is. A big plus is that the data is read separately and independently from each wheel. This allows you to distribute the braking actions as correctly as possible, avoiding losses in control.

The principle of operation of EBD can be characterized by the usual simple example of tug of war. As long as both teams are applying equal effort to tug, the rope is in a stationary position. But if at least one participant in the competition folds his hands, most of the rope will be on the side of the rivals. The analogy is visible in the case of EBD. In order to avoid the car stalling into a skid, the electronics evenly distribute efforts to help the weakened wheel, if necessary, weakening others.

Difference between ABS and EBD

EBD is a kind of continuation, an assistant to ABS. The main difference between EBD and ABS is the fact that the driver is assisted not only during emergency braking, but also every time you press the pedal in normal situations. EBD always assists the driver in the management of any kind of braking. The EBD system analyzes the position of each wheel separately during braking, distributing the necessary force among them. Such a system works well when braking on turns on mixed surfaces, saving the directional stability of the car, in which the center of mass is shifted towards the outer radius of the wheels. In this case the forces of the brake system are distributed as between automobile axles and between all wheels. EBD is more effective at helping to maintain trajectory and minimize the likelihood of skidding than ABS.

History of EBD

The EBD system technology is not new enough. Its development by engineers began in the last century. And already in the late 80s, new cars were successfully equipped with this system. Developers working for the automotive giants have noticed that the ABS system does not fully cope with the task that is entrusted to it. Studies have shown that when braking, the main load is taken by the front wheels.

The anti-lock braking system, of course, prevented the wedge of the front wheels, but the rear ones remained without movement, which contributed to the skidding of the car.

Studies carried out in the design offices showed that the braking forces were evenly distributed between all the chassis of the car, but the wheels were subjected to completely different conditions. The fundamental factor was the adhesion of the wheels to the braking surface. As a result each wheel behaved individually. Due to the fact that the rear wheels were blocked, this led to the throwing of the car body from side to side. The free movement of the front wheels contributed to the driver's control of the car. All these indicators influenced the development and creation of the EBD brake force distribution system.

On what vehicles is it installed?

Anti-lock braking systems were originally planned to be used in the aviation industry, but it was not possible to establish mass production in large volumes. Later, as you know, ABS began to be installed on cars and motorcycles.

In our time EBD in combination with ABS is installed on most trucks and cars, motorcycles, in order to exclude the possibility of the driver flying over the steering wheel and even trailers.