Audi R8 e-tron track drive, Berlin Tempelhof AirportEnlarge Photo
Audi is launching a technological offensive over the next few years, and among its innovations are a new hybrid powertrain and a wheel design featuring active aerodynamics.
The details were revealed in patent drawings, and were spotted by Autocar.
Most complex, though perhaps most interesting, is Audi's patent for a new hybrid system.
At first glance, it doesn't look particularly unusual. Likely to carry the e-tron quattro tag, it's a through-the-road hybrid system designed for use in Audi's future quattro all-wheel drive models.
With no mechanical link between front and rear wheels, the back axle's power is supplied by an electric motor. Similar systems have been used by PSA Peugeot-Citroen in the French automaker's small series of hybrid models.
Audi's unique touch is to give the electrically-powered wheels much greater control of torque. Not just in acceleration, but deceleration too, when the car is recovering energy through regenerative braking.
The theory is that strong regenerative braking can cause the back wheels to break traction on slippery surfaces. If the back wheels slip or lock while you're slowing down on snow, ice or a very wet road, you're gonna have a bad time.
By precisely measuring the grip at the rear wheels--under deceleration, as well as accelerating--the system can vary the strength of the regenerative braking to ensure the wheels don't slip. If you're driving on ice, the regenerative braking would be relatively weak, but return to normal should the wheels detect a grippy surface.
Naturally, precise control of driven wheels also has regular traction benefits, meaning Audi's electronic quattro could react faster than any conventional torque-distributing all-wheel drive system.
The company's other unique patent application is for another technology we've seen recently, albeit on an Audi vehicle itself.
A car's wheels can generate surprisingly high aerodynamic resistance as they turn, and several automakers equip fuel-efficient cars with drag-minimizing wheel designs to limit this resistance.
Audi's plan is to use active shutters between the wheel spokes, that close at speed to minimize resistance but have the ability to open for brake cooling.
A very similar system was used on the Audi R8 e-tron electric supercar we drove last year. There's only an inch or so difference between the shutters' open and closed positions, but it's enough to serve the desired purpose.
Eventually, such systems could find their way into every vehicle, to the benefit of both style and aerodynamic efficiency.