For specific Audi RS models, sport suspension plus with Dynamic Ride Control (DRC) is a highly dynamic dampening technology. The driver can change the single-tube dampers’ variable characteristic in three steps. Shock absorber pairs that are diagonally opposed to one another are connected by hydraulic lines and a central valve. The valves control the oil flow in the shock absorber of the front wheel with the spring deflection when cornering quickly. They give more support and lessen pitch and roll motion. This enhances handling by allowing the car to follow the road more closely.
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Dynamic steering
Depending on the driving speed, steering angle, and chosen mode in the Audi drive choose handling system, dynamic steering can change the steering ratio by up to 100%. The superimposition gearing in the steering column, which is powered by an electric motor, is the main part. Its design, known as strain wave gearing, is small, light, and torsionally stiff. It has little friction, is precise, and is free of play. The gearing is highly efficient and capable of transferring large torques very quickly.
The strain wave gearing only needs three essential parts to function. A thin-walled sun wheel is deformed by an electric motor rotating an elliptical internal rotor, which is coupled to the steering input shaft by a ball bearing. It meshes with a hollow wheel with a sprocket that works on the steering output shaft at the vertical axes of the ellipse. The internal rotor’s rotation causes the ellipse’s large axis to move into the area where the teeth engage. The sun wheel and hollow wheel move in relation to one another because the sun wheel has fewer teeth than the latter. The fast-running electric motor’s huge gear ratio makes it feasible to build up this ratio precisely and quickly.
Dynamic steering works very directly when driving at moderate speeds in city traffic and when navigating; it only requires two complete revolutions of the steering wheel to move from one end stop to the other. Because of the substantial power steering increase, parking maneuvers are incredibly simple. The directness of the steering reaction and the steering power assist gradually decrease on country roads. Indirect gear ratios and low power assist are employed at high expressway speeds to calm down jerky steering movements and permit excellent straight tracking.
To accomplish sporty handling and driving safety, dynamic steering tightly cooperates with the electronic stabilization control program, or ESC. It countersteers slightly if necessary; in the vast majority of circumstances, its minimal interventions, the most of which are undetectable to the driver, mitigate understeer and oversteer caused by load changes. The technology assists with stabilizing steering inputs when stopping on surfaces with divided friction coefficients.
Dynamic steering can make corrections more quickly than the brake system can increase wheel pressure. The principal workbrake operations it handles frequently either stop being necessary or are reduced to dampening effects that slow down driving. At high speeds and on slick terrain like snow, the benefits in terms of driving safety and sportiness stand out the most.
Electrohydraulically integrated brake control system
The Audi e-tron is the first electric series production car to feature a brake control system that is electrohydraulically integrated. Hydraulic, electrical, and electronic actuators are used to operate the wheel brakes, reinforcement, and activation, respectively. Within milliseconds, the control unit determines how hard the driver is pressing the brake pedal and calculates how much braking torque is required. If the recovery torque is insufficient, more hydraulic pressure for the traditional friction brake is produced. The displacement piston, which is propelled by an electric spindle drive, forces braking fluid into the brake lines. The driver is not aware of the seamless change from the engine brake to the pure friction brake. The familiar pedal sensation for the driver’s foot is produced by a second piston using a pressure-resistant component. The brake pedal simulator ensures that the driver is not impacted by hydraulic issues. When ABS is used to brake, pressure buildup and decrease do not manifest as grating, loud pulsations.
When the driver presses the left pedal firmly enough to cause a deceleration greater than 0.3 g, the electrohydraulic brake system is engaged; otherwise, the Audi e-tron slows down using recuperation from its two electric motors. The brake control system precisely and nearly twice as quickly as a conventional system builds up brake pressure for the wheel brakes. There are only 150 milliseconds between the start of the brake application and the presence of the maximum brake pressure between the pads and disks when automated emergency braking is used. Impressively low braking distances result from this, which takes hardly longer than a blink of an eye. Because wheel brakes are more effective than electric braking in this situation, the car decelerates even at extremely low speeds, such as those experienced during maneuvering. Otherwise, the electric motor would have to actively slow down at low rotational speeds, draining important battery current.
The electrohydraulically integrated brake control system’s “brake-by-wire technology” permits a bigger air gap, or a greater separation between the brake pad and brake disk, to be adjusted. As a result, the likelihood of friction and heat generation is reduced, actively extending the vehicle’s range.
Electromechanical active roll stabilization
With electromechanical active roll stabilization, a wide range between smooth build-up and lively handling is guaranteed. Between the two stabilizer portions on each front and rear axle is a small electric motor with a three-stage planetary gear set. The suspension control makes sure that both stabilizer halves behave mainly independently of one another when traveling straight ahead. This improves ride comfort by lowering vibrations caused by sprung mass on uneven roadways. However, at fast speeds, the goal is to achieve the best roll compensation. The transmission of the electric motor rotates the stabilizer’s halves in opposite directions as a unit, reducing the roll angle when cornering and making the car’s handling even more firm and dynamic.
Electromechanical active roll stabilization serves as a recuperative system and is powered by a strong 48-volt electrical subsystem: The stabilizer is excited when the wheels on one axle deflect to significantly different degrees as a result of road imperfections; the electromechanical active roll stabilization motor now turns each impulse into electrical energy. The lithium-ion battery of the electrical subsystem stores this energy, making sure that the electromechanical active roll stabilization has a much better overall energy balance than a hydraulic system. Active roll stabilization also requires minimal maintenance because it doesn’t utilize oil.
Electronic chassis platform
The electronic chassis platform (ECP) serves as the chassis’ main control panel. It keeps track of the vehicle’s speed, height values, vertical, roll, and pitch motions as well as the road’s coefficient of friction and the current driving condition, such as under- or oversteer, as well as information on the associated suspension systems. It swiftly determines and carefully coordinates the optimal function of these components based on these. The consumer notices ride characteristics more clearly as a result of the central control, including accurate cornering, enhanced dynamics, and a high level of ride comfort.
Adaptive air suspension
Adjustable air suspension A regulated damping air suspension system offers a wide range between comfortable cruising and competitive performance. It independently changes the ride height based on the speed and the driver’s preferences and the road conditions. As a function of load, the air suspension also provides level control.
Various specific product lines have different system designs. Shock absorbers are enclosed by air springs in the front suspension struts. These two parts are often applied individually in the rear suspension of vehicles. However, pneumatic struts are also mounted on the rear suspension of the Audi A8 (2017). Depending on the type, the compressor’s mounting position and the quantity of pressure reservoirs that must be filled also vary.
The electronic chassis platform (ECP), the primary chassis control unit, individually regulates the operation of each wheel’s shock absorbers at cycles in the order of milliseconds depending on the state of the road, the driver’s driving technique, and the mode selected in the Audi drive select dynamic handling system. The hydraulic fluid’s volumetric flow is adjusted using solenoid damper valves.
Audi dynamic suspension is air-sprung, right?
The new Q7 from Audi comes standard with a balanced steel spring suspension. All seven-seaters come equipped with adaptive air suspension as standard equipment and as an option. The customer obtains the sport adaptive air suspension, which is a little firmer, with the S line exterior. As a result, when the body is at its natural level, it is 15 mm (0.6 in) lower. The Audi drive choose dynamic handling system allows the air suspension to be switched between four settings. It enables level control and can adjust the body’s level position by up to 90 millimeters (3.5 in), depending on the driver’s needs and the driving environment. Depending on the road speed, the ride height automatically lowers on highway trips by up to 30 millimeters (1.2 in) (by about 15 millimeters (0.6 in) with the sport air spring), which increases aerodynamic drag and, consequently, efficiency. The “Raise option in Audi drive choose allows up to 60 millimeters (2.5 in) of extra ground clearance to be selected when traveling off-road at low speeds.
What does the Audi Q5’s dynamic suspension do?
Audi refers to its standard fixed suspension as dynamic. Only the variants with adaptive suspension react to changing road conditions. 10/04/2020 10:15 PM, HankJ
Which suspension is used by Audi?
I frequently get the question of what makes an Audi feel like an Audi. The handling characteristics of an Audi are undoubtedly unique, but they are too delicate to be noticed from the cabin. The front suspension setup holds the key. If you’ve ever had to fix the front suspension on an Audi or a Volkswagen and wondered why it had to be so difficult, I can tell you that everything is there for a purpose.
In my opinion, Quattro is the best feature of an Audi, with multi-link suspension coming in second. It drives well on motorways, corners amazingly well, and provides the driver the confidence to test the limits of their vehicle. Only a few Volkswagens and certain Audis have multi-link suspension. The Phaeton and B5 Passat use it, although the A3, TT, and Q7 do not because they are built on Volkswagen and Porsche chassis.
Having several points of contact between the body and wheel is the basic concept. Multi-link suspensions use up to five control arms as opposed to the Golf/Jetta arrangement, which just uses a control arm and strut. The usual Audi design includes a steering rack positioned on top of the firewall, a strut assembly, and a total of four control arms on each side (two upper arms and two lower arms). The camber, caster, and toe can be easily managed even on uneven roads and under hard acceleration and braking thanks to the large number of points of contact that are dispersed over such a large area.
The suspension system of an Audi is essentially a double wishbone layout, except there are two arms, each with a bushing and ball joint, as opposed to one triangle arm on top or bottom with two bushings and a ball joint. This permits the wheel to move forward and backward in a defined range in response to the loads and forces acting on it, without significantly altering the geometry.
But all of this has a price. a direct monetary expense. Audis have four control arms on each side, with four bushings and four ball joints, as opposed to one control arm, one ball joint, and two bushings. Although replacing these control arms is not difficult, hiring a professional to do it for you could cost a fortune. It’s not too difficult to diagnose and make the necessary repairs if you think your front suspension is about to fail.
Bushing failure’s early stages are marked by tiny fractures that are deeper than surface cracks.
You most likely have a bad ball joint if you hear popping sounds when turning or going over bumps. Lifting the front tires off the ground and shaking the front wheels side to side is the simplest technique to inspect. A ball joint has play if you hear or feel a popping or clicking sound, and the entire arm needs to be replaced. Put your palm over the ball joints to feel which one is popping to identify which ball joint it is.
Your bushings may be the cause of your suspension feeling sloppy or hazy. The upper arms break down frequently, and you may detect when they need to be replaced by performing a quick visual inspection. Turn the wheels from lock to lock while they are off the ground, checking the bushings along the way. Rubber should be replaced if it has severe tears or deep fissures.
I advise utilizing high-quality components, as with all suspension repairs, and having an alignment done thereafter. Put everything back where it was removed from in order to properly preload the bushings and prevent early wear on them. If your suspension doesn’t track straight and wears down your tires, there’s no use in replacing it with a component costing hundreds of dollars. Your Audi or Volkswagen’s suspension will take care of you if you take good care of it.
What are your personal experiences with multi-link suspension, which is not just used by Audi?
Authored by:
From Berkeley, California, Chris is a journeyman mechanic who specializes in late-model Volkswagens and Audis. His spare time is spent completely rebuilding every part of his 1983 Rabbit GTI since he is a glutton for suffering.
What is the suspension with Audi dynamic ride control?
Audi Dynamic Ride Control, also known as DRC, is a purely mechanical damping technology that monitors the road’s conditions and cornering forces and modifies the suspension as necessary.
The vehicle’s longitudinal and transverse movements are countered by this cutting-edge dampening technology. Each diagonally opposed damper on the opposite side of the vehicle is connected to the two shock absorbers on the same side by a single central valve.
The middle valve between the diagonally opposed shock absorbers creates a flow of oil when a corner is taken, adding additional dampening force. The damper characteristic is altered when the suspension is compressed on one side, almost eliminating rolling or pitching motions.
This mechanically active damping technology consequently makes sure that the car retains extremely good tracking stability when cornering and reacts precisely to steering wheel adjustments.
To precisely pressurize the system after maintenance and return your Audi DRC to factory settings, SJB Autotech has the authorized tools.