Who knows what an adaptive suspension is and how it works, then you can safely close this page, who does not know - you are welcome. In this publication, we will try to understand the design of this system, its secrets and features that distinguish it from other similar designs.

First, let's deal with the essence and terminology. Main Feature adaptive suspension (by the way, it is sometimes called active) is that it can change the stiffness of shock absorbers, the so-called damping, depending on the condition of the roadway, driving style and other similar parameters.

It is clear that all major automakers would like to have such a system in their arsenal, because it is a real find for modern car. So it is, and every self-respecting company, knowing what an adaptive suspension is, considered it necessary to create its own version of this technology.

For example:

1. At Toyota, it is called Adaptive Variable Suspension, which is abbreviated as AVS (we already mentioned it);
2. Mercedes-Benz has an Adaptive Damping System or ADS;
3. Bavarian engineers from BMW have named their version of the adaptive suspension Adaptive Drive;
4. Volkswagen Adaptive Chassis Control - DCC;
5. Opel called Continuous Damping Control - CDS, and so on...

It is not uncommon to combine an adaptive circuit with an air suspension to achieve even greater levels of comfort, which, for example, a business class car needs. This is what Mercedes did with ADS technology, in addition, a similar system is used in Audi.

Adaptive suspension for top cars

Although the adaptive circuit has almost as many names as automakers, there are currently only two methods for adjusting damper stiffness:

• electromagnetic valves;
• magnetic rheological fluid.

The systems we listed above, namely AVS, ADS and Adaptive Drive, use solenoid valve technology.

How it works?

As you know, the shock absorber is filled special liquid, and depending on how freely it moves inside it, its rigidity will also change.

In this case, the shock absorber is adjusted by changing the flow section of the valves - the narrower they are, the worse the fluid circulates and the stiffer the suspension becomes. Accordingly, if you increase the cross section, the shock absorbers become softer.

The valves are controlled by electrical signals from the control unit, which, based on its calculations, sets the required “clamping” level for them.

Audi Q7 adaptive suspension system (pneumatics):

Shock absorbers with magnetic rheological fluid are less common. Such systems are used in some Cadillac models, Chevrolet and Audi.

A liquid with such a complex name has one interesting property due to the metal particles that it contains - when a magnetic field is applied, these same particles line up in a certain order.

This allows you to adjust the flow sections in the shock absorbers without valves, the only thing you need is to find the source of the magnetic field, for which coils are used, through which an electric current flows.

As in the case of valves, fills them with work the electronic unit management.

Everything's under control!

As already mentioned, control over the operation of the adaptive suspension is assigned to the control unit. He is subordinate to a scattering of sensors that track the acceleration of the car in the vertical plane, as well as the magnitude ground clearance depending on suspension travel.

The system can perform some actions both automatically and controlled by the driver.

In the first case, it is allowed to change the level of suspension stiffness depending on the condition of the roadway, as well as maintain body stability in corners, during acceleration and braking.

The driver, as a rule, can manually set the degree of stiffness of the shock absorbers, and usually he is given a choice of three modes: comfortable (the softest), sporty (the most clamped) and normal (something in between the first two).

In conclusion, a few words about the pros and cons ... Although, what disadvantages can the adaptive suspension have, except for the high cost, otherwise there are only advantages, which is the reason for its use in the most expensive and luxurious cars.

That's all for the theoretical part, I tell you, until we meet again on the pages of our blog, friends! And you watch a few short videos (not in Russian) on this system.

Watch right here on the site without going to YuoTube!

AVS system from Toyota:

BMW Adaptive Drive System:

System from General Motors with magnetic rheological fluid:

First, let's define what a suspension is needed for. It acts as a buffer between the road and the car body. Without it, all the bumps would be transmitted to the body. The spring, as a suspension element, when the wheel encounters an unevenness, takes on the impact energy, compressing. But later she will give it back, which will cause the body to sway. This is where the shock absorber comes into play, which will absorb this energy due to hydraulic resistance, and turn this energy into heat.

Suspension AVS and similar

Manufacturers of various car brands have created a huge number of adaptive suspensions, with various options for the implementation of certain options. But the essence of adaptive suspension, also called active suspension, boils down to the fact that it is able to adapt to road conditions. Also, at the request of the driver, the stiffness of this suspension can be optionally changed, that is, from the control unit. Consider some options for this type of suspension.

Abbreviation avs (Adaptive Variable Suspension), in the common people adaptive suspension, is used Toyota manufacturers and Lexus, but this does not mean that other cars do not have it. Everyone just calls her in their own way.

• BMW has Adaptive Drive;
• Opel calls it Continuous Damping Control (CDC);
• Porsche called its active suspension management Porsche Active Suspension Management (PASM);
• Volkswagen's adaptive suspension control is called aDaptive Chassis Control (DCC);
• The stiffness of the dampers at Mercedes-Benz is monitored by the adaptive damping system -Adaptive Damping System (ADS).

As you can see, a lot of bright minds are working in the field of improving driving comfort, and the results of this work are more than noticeable. Let's look at the most interesting implementation options for active suspension.

Shock absorber damping system

To date, there are two options for implementing this type of suspension:

1. electromagnetic control valve;
2. magnetic rheological fluid.

In the first case, under the influence of electric current on the valve, the through holes increase or decrease, thereby changing the stiffness of the suspension.

The liquid option is also based on electricity. The liquid is not simple, and contains metal particles, which, when an electromagnetic field is created, line up in a certain order, the resistance of the liquid changes, it seems to become thicker, thereby changing the characteristics of the shock absorber.

BMW Adaptive Suspension

An adaptive suspension option from bmw, called Dynamic Drive, coupled with an electronic damping control system (based on the same solenoid valves), provide excellent comfort when driving bmw.


Sensors located front and rear bmw car, in a split second they catch a roll in one direction or another, and are able to adjust each rack separately. That allows you to almost nullify pecking when braking, and slopes in corners. Tests have shown that this system has a positive effect on the braking distance during an emergency stop of the car.

The switches allow the driver to choose one of several driving options:

• comfortable;
• normal;
• sports.

Dynamic control system

Very interesting implemented adaptive suspension in Opel cars, with their IDS and CDC systems. They also allow you to adjust all the racks of the car separately from each other. And the new generation of FlexRide suspension allows you to select a sporty, dynamic suspension mode, or soft and comfortable at the touch of a button. At the same time, the system changes not only the characteristics of the shock absorbers, but also the gas pedal, steering and dynamic stabilization. In standard mode, Opel's active suspension adapts itself to your driving style.

Active Suspension Control System

Porsche active suspension management on Porsche cars, connects the computer to all the racks of the car, and adjusts their rigidity as well as ground clearance. With its help, the manufacturer managed to solve main problem previous cars of the 911 series - unpredictable behavior of the car when entering turns.


The active system takes into account readings both from sensors on the body and reads the steering angle, speed, pressure in brake system, and on the basis of this gives a command to the valves in the racks. The tighter the turn, the stiffer the stance becomes, which means the car's position is more stable.

Volkswagen Adaptive Suspension

Adaptive Chassis Control (DCC) has several sensors for ride height and body acceleration, information from which is continuously fed to the control unit. The more bumps in the road, the stiffer the active suspension will become in order to reduce body sway.

Air suspension from Mercedes-Benz

the Adaptive Damping System, which is implemented in the Airmatic Dual Control air suspension, monitors the stiffness of the shock absorbers and sets the ground clearance based on the speed and load of the car. There is also a more affordable version of the adaptive suspension in the arsenal of this manufacturer - with mechanical adjustment devices.

As you can see, the variety of active suspension implementation options is quite large. All of them are good in their own way, it is quite possible that each has its drawbacks, but one thing is certain - in pursuit of a buyer, manufacturers (be it bmw or porsche) are forced to constantly improve product quality and offer something that others do not yet have. Active suspension is a clear proof of this.

Installed in modern cars suspension is a compromise between comfort, stability and handling. Suspension with increased rigidity, guarantees a minimum level of roll, respectively, guarantees comfort and stability.

The soft suspension is characterized by a smoother ride, while when performing maneuvers, the car sways, which leads to increased instability and poor handling.

Therefore, automakers are striving to develop the latest active suspension designs.

The term "active" means such a suspension, the main parameters of which change during operation. Embedded in it electronic system allows you to change the desired parameters in automatic mode. The suspension design can be divided into its elements, for each of which the following parameters change:

Some types of construction use the impact on several elements at once. Most often, active suspension uses shock absorbers with a variable degree of damping. This suspension is called adaptive suspension. Often this type is referred to as a semi-active suspension, due to the fact that it does not contain additional drives.

To change the damping capacity of shock absorbers, two methods are used: the first is the use of electromagnetic valves, as well as the presence of a special magnetic rheological type fluid. The shock absorber itself is filled with it. The degree of damping of each shock absorber is controlled individually and is carried out by an electronic control unit.

Known suspension designs of the adaptive type described above are:

• Adaptive Chassis Control, DCC (Volkswagen);
• Adaptive Damping System, ADS (Mercedes-Benz);
• Adaptive Variable Suspension, AVS (Toyota);
• Continuous Damping Control, CDS (Opel);
• Electronic Damper Control, EDC (BMW).

The active suspension option, in which special elastic elements are implemented, is considered the most versatile. It allows you to constantly maintain the required height of the body and the rigidity of the suspension system. But from the point of view design features, it is more rigid. Its cost is much higher, as well as repairs. In addition to traditional springs, hydropneumatic and pneumatic elastic elements are installed in it.

Suspension Active Body Control, ABC from Mercedes-Benz regulates the level of rigidity using a hydraulic actuator. For its operation, oil is injected into the shock absorber strut under high pressure, and hydraulic fluid acts on the coaxially located spring.

The shock absorber hydraulic cylinder control unit receives data from 13 different sensors, including sensors for longitudinal acceleration, body position, and pressure. The presence of the ABC system virtually eliminates the occurrence of body roll when cornering, braking and accelerating. With an increase in the speed of the car over 60 km / h, the system automatically lowers the car by 11 mm.

The air suspension is based on a pneumatically elastic element. Thanks to him, it becomes possible to change the height of the body relative to the roadway. Pressure is injected into the elements by means of a special electric motor with a compressor. The stiffness of the suspension is changed with the help of damped shock absorbers. It is on this principle that the Airmatic Dual Control suspension from Mercedes-Benz was created, it uses the Adaptive Damping System.

Elements of hydropneumatic suspension allow you to adjust the height of the body and the stiffness of the suspension. The suspension is adjusted with a high pressure hydraulic actuator. The hydraulic system is powered by solenoid valves. One of the modern examples of such a suspension is the third generation Hydractive system installed on Citroen cars.

A separate category of active type suspensions includes structures that include anti-roll bars. In this case, they are responsible for the stiffness of the suspension. Moving in a straight line, the stabilizer does not turn on, the suspension moves increase. Thus, handling on rough roads is improved. When cornering or rapidly changing direction, the stiffness of the stabilizer increases, thereby preventing the occurrence of body roll.

The most common types of suspension are:

• Dynamic Drive from BMW;
• Kinetic Dynamic Suspension System, KDSS from Toyota.

An interesting version of the active suspension is installed on Hyundai cars. This is the system active management suspension geometry (Active Geometry Control Suspension, AGCS). It implements the ability to change the length of the levers. They affect convergence rates rear wheels. When driving straight and performing maneuvers at low speed, the system selects the minimum convergence. When performing maneuvers at high speed, it leads to an increase in convergence, which improves handling. The AGCS system interacts with the stability control system.

Any car is equipped with a suspension - movement without it would be quite difficult and uncomfortable. The main element in a simple suspension is a spring, which takes the brunt of the impact of the wheel meeting with road surface defects. At this moment, it is compressed, but then the absorbed energy is released, and a shock absorber is provided for its absorption. The mode of operation of the standard suspension is always the same.

Adaptive adjustable suspension AVS is arranged a little differently - it is able to adapt to specific road conditions. Rigidity can be changed by means of a control unit located in the cabin. Such a system allows you to improve the handling of the car, reduce fuel consumption and tire wear. So, when driving on a flat highway, it will be appropriate rigid suspension, which ensures the stability of the car when maneuvering at high speeds. When driving at low speed over bumps, comfort increases along with a decrease in stiffness.

Adjustment system in adaptive suspension

Each automaker, when installing an adaptive suspension in their cars, calls it differently, but the meaning does not change. The degree of rigidity of the active suspension can be adjusted in only two ways:

• through valves with electromagnetic control;
• using a liquid with magnetic-rheological properties.

The solenoid valve is able to change its orifice depending on the strength of the current flowing to it. If it is necessary to make the suspension more rigid, current must be applied to the valve high voltage which significantly slows down circulation. working fluid, and the suspension is made as rigid as possible. When a low voltage is applied, the suspension is made as soft as possible, since the hydraulic fluid is allowed to circulate relatively freely.

Magnetic rheological fluid suspension functions a little differently. The liquid itself, containing special metal particles, is able to change its properties under the influence of an electromagnetic field. The suspension is equipped with special shock absorbers that do not contain traditional valves - they are replaced by special channels for fluid circulation. They have shock absorbers and built-in coils that generate an electromagnetic field, under the influence of which the properties of the liquid change, which allows you to change the damping parameters.

Operating modes

Adjustment of the degree of rigidity of the vehicle's adaptive suspension occurs almost completely automatically. The entire control system consists of the following main elements:

• Control block;
• input devices - ground clearance and body acceleration sensors;
• actuators - valves and coils of the shock absorbers themselves.

As a rule, the system also has a mode switch located in the cabin, allowing a person to select the preferred stiffness mode, in accordance with specific conditions. When driving, the control unit constantly reads the signals from all sensors, analyzes the degree of travel of the shock absorbers and the resulting body roll. The number of sensors may vary depending on the brand of car, but there must be at least two - front and rear.

The received signals are processed and signals are generated for the actuators in accordance with the program selected by the driver, which, as a rule, are three - normal, comfortable and sporty. For a more correct functioning of the adaptive suspension, its control unit constantly "cooperates" with other auto systems: steering wheel, gearbox, engine management system. This achieves the most accurate functioning of the active suspension.

Advantages of active suspension

Any car equipped with an adaptive suspension has many advantages over a car with its standard version. The main advantages of adaptive suspension include the following:

• significantly increased comfort for the driver and passengers;
• less tire wear;
• excellent handling car on high speed, when making sharp maneuvers;
• reduced braking distance on any road surface.

Sensors are responsible for the reaction speed of the suspension. It is they who constantly monitor the position of the body, which changes during sharp acceleration / braking, when entering a turn, especially a steep one. The level of damping of the suspension elements when the body loses its correct position will immediately change. This achieves the constant maintenance of an exclusively horizontal position of the body, which allows you to maintain full control over the car. For more information about the operation of such a system, you can watch the video:

An important aspect in the operation of the active suspension system was its interaction with other auto systems. So, changing the operating mode of the suspension not only changes the characteristics of the shock absorbers themselves, but the settings of the gas pedal, steering wheel, and dynamic stabilization system change independently. This allows you to not only get a safer, but also easier to drive car. Depending on the specific manufacturer, the adjustable suspension can also take into account the load on the vehicle.

Any car equipped with active suspension has many advantages on the road compared to standard options. At the same time, many automakers provide for automatic adjustment of the suspension in standard mode - the driver does not need to constantly switch modes, the system will automatically adjust the optimal stiffness depending on the number of bumps on the road, the degree of acceleration, and a number of other parameters.

Adaptive suspension, like any other suspension system, is a set of components and mechanisms that provide comfort and safety for the driver and passengers. The quality of the suspension depends on the handling and stability of the car, as well as the service life of other components and mechanisms. Therefore, more and more motorists are opting for an adjustable suspension that adapts to any type of road surface.

Principle of operation

An adaptive suspension is a type of suspension that automatically changes its characteristics (adapts) while driving. We note right away that active suspension is a general definition, and an adaptive suspension system is a variation of it.

General view of the adaptive suspension

For successful operation, the system needs to collect information about the current driving conditions of the car - this is done by various sensors and sensors. The analyzed information includes the type of road surface, body position, driving parameters, driving style and other data (depending on the type of adaptive chassis). Then the electronic control unit comes into operation, which analyzes the data received from the sensors in a fraction of a second and sends control signals to the actuators - active racks and stabilizers roll stability. As a result, the mechanism instantly adapts to specific conditions.

When receiving a command from the block manual control suspension, the suspension system will begin to adapt to the mode selected by the driver. Three suspension modes are commonly used: normal, comfortable and sporty.

Elements of adaptive suspension

Adaptive suspension usually includes the following elements:

• electronic suspension control unit;
• adjustable anti-roll bars;
• active (adjustable) shock absorber struts;
• sensors (body acceleration, rough roads, ground clearance, and others).

Automakers can apply various suspension systems, while their general principle actions are always the same.

Electronic control unit

The electronic control unit is an element of the system that controls the modes of operation of the suspension. This element analyzes information from sensors or receives a signal from a manual control unit controlled by the driver. Accordingly, in the first case, the adjustment occurs automatically, and in the second - in manual mode.

Adjustable anti-roll bar

This element changes the degree of its rigidity on a signal from the control unit. are activated when the car is maneuvering. The adaptive suspension uses this component to reduce vehicle body roll. Modern systems suspension controls receive, analyze and send signals to the actuators in milliseconds. This allows you to instantly change suspension settings.

Active (adjustable) shock absorber struts

Active shock absorber with magnetic rheological fluid

This element quickly responds to the type of road surface and the mode of movement of the car, changing the degree of rigidity of the suspension system. There are active shock absorber struts with solenoid valve, as well as with magnetic rheological fluid. The first type of racks changes the stiffness of the suspension with the help of an electromagnetic valve, which has a variable section. The cross section itself changes depending on the voltage supplied by the electronic control unit. The second type of active shock absorber struts is filled with a special fluid that changes viscosity due to the action of an electromagnetic field. Resisting the passage of fluid through the damper valves increases the stiffness of the suspension.

Sensors

Bosch acceleration sensor

Adaptive suspension sensors are devices designed to measure various quantities and send information to the electronic control unit. The body acceleration sensor constantly evaluates the quality of the road and is triggered when the car body sways. The Rough Road Sensor responds to uneven road surfaces by sending a signal in the event of vertical oscillation. Thanks to this sensor, the electronic control unit "learns" in a timely manner about the passage of unevenness. The body position sensor communicates with the control system during various vehicle maneuvers (acceleration, braking), when the rear of the car becomes lower than the front and vice versa.

Main differences

Standard suspension, which is installed on budget cars, is limited in its capabilities: it provides the car with good handling on the track or comfort on rough roads. The adaptive suspension has two main differences from the standard suspension - it adapts to the current road surface and driving style. This is a new level of suspension, which is a system with many sensors and active mechanisms. When driving a vehicle with adaptive suspension, the driver may not notice the change in road quality.

This type of adjustable suspension cannot be called an innovation, since this complex structure has been installed on cars for more than a year. However, more recently, automakers have managed to make it more compact, while increasing functionality.
Improvements to this part of the car have also reduced body roll and improved agility.

Advantages and disadvantages

Benefits of adaptive suspension:

• the best driving performance car;
• comfort and safety of the driver and passengers while driving.

The main drawback of the adaptive suspension system is its price. Its presence can increase the initial cost of the car by an order of magnitude. At the same time, owners of a car with this type of suspension should remember that the cost of its maintenance will also increase in the future.

Application

The most widespread are adaptive suspensions with a solenoid valve in active shock absorber struts. Such a set of mechanisms is installed on Opel, Volkswagen, Toyota, Mercedes-Benz cars. Chassis with magnetic rheological fluid is not very popular. It can be found on Audi cars, Cadillac and Chevrolet.

Manufacturers active suspensions do not stand still. They combine all available options in order to improve their performance, as well as reduce size and weight. The main task is to achieve unique settings at any given time for each individual wheel. This will take the comfort and safety one step further, as well as improve the handling and stability of the car.