High-Tech Product Furthers Audi's Drive To Bring 'Advantage Through Technology
When Audi's new TT coupe hits European roads the vehicle will have the great style and performance it hascome to be known for since its introduction.
But drivers will notice something different about the new version of this famous sports car -- better transient handling and road isolation
along with increased driver comfort, and the ability to select the level of suspension damping with a console-mounted two-position driver preference switch.
Audi is equipping its new TT with Delphi Corp.'s MagneRide semi-active suspension -- an innovative technology that uses magneto-rheological fluid to provide continuously variable real-time suspension damping control.
Named Audi Magnetic Ride on the TT, MagneRide responds in real time to road and driving conditions based on input from sensors that monitor vehicle body and wheel motion.
"Audi's work to bring 'Advantage Through Technology' allows MagneRide to enhance the TT's great handling and performance characteristics with increased ride comfort, greater vehicle body motion control and improved transient handling capability," said Daniel Warrell, Delphi Chassis Systems business line executive. "MagneRide will help make a great car even more purposeful and enjoyable."
Audi Magnetic Ride is based on a magneto-rheological principle. When in a magnetic field, small iron particles in the suspension fluid align themselves in the direction of the magnetic flux. The electromagnetic coil
is integrated into the damper piston in such a way that when it is energized the magnetic flux runs exactly transversely to the admission
ports in the damper piston. If the piston moves, the aligned iron particles create flow resistance in the flowing suspension fluid.
The greater the energy applied and the stronger the magnetic field, the greater the resistance and damping power. The energy is controlled in
relation to driving dynamics and impulses from the road. This means for every road situation optimal damping power is available. This damping power produces -- according to OEM desire -- a more comfortable feel or sportier vehicle handling.
Audi uses the magneto-rheological dampers for both -- comfort and sport. In its basic mode, the suspension allows for a more comfortable
vehicle feel. In sports mode, the vehicle offers a sportier ride thanks to a push of a button.
Because of the lower level of damping force in basic mode, the total path of the springs is fully utilized. This assures top comfort over long distances and when driving over uneven surfaces.
The greater damping of the sports mode results in tighter, sportier handling along with better control in the threshold. It also optimally
suppresses the rolling tendency of the car's body in corners.
Since no mechanical parts must be moved, the Delphi technology responds extremely spontaneously. The damping force is only dependent on the power applied to the magneto-rheological fluid and can be adjusted up to 1,000
times a second. Thanks to the variable control of the power, the damping force can also be set infinitely. This means the magneto-rheological
dampers respond almost in real time with great sensitivity to impulses from the road. The control system loop with Skyhook algorithms ensures the greatest possible road-to-wheel contact in the case of uneven road surfaces
with the least impulses to the car body. This means the Audi TT with Magnetic Ride has the greatest possible driving dynamics and allows for
comfort.
Delphi's magneto-rheological monotube damper requires roughly the same space requirements as conventional dampers or struts. If required, Delphi supplies the complete semi-active system with dampers and struts including the sensors and the control unit.
For Audi, the low energy requirements of the system are another benefit. On average, a damper requires just 5 watts of electrical capacity
(25 watts at a maximum).
"The new TT equipped with MagneRide will assist drivers in truly enjoying driving at the speeds experienced on Germany's Autobahn while also
offering refined ride quality on city streets and secondary roads," said Warrell.