"Racing improves the breed!" The idea that lessons learned and technology proven on the race track can be transferred to production vehicles has long been a justification for automakers participation in auto racing.
For this year's Le Mans 24-hour race, Audi is reversing that concept by installing a feature now common in production cars – a rear-view camera – in its fleet of Le Mans racers.
Rather than just being 'on' when a car is reversing, which is the system's normal function in a production car, it will become a full-time digital rear-view mirror.
Vision, especially to the rear, is a major challenge in closed LMP sports cars, like the Audi R18. The design itself, with its monocoque structure and its mid-engine configuration, leaves no room for a rear window.
Used for the first time in a closed LMP sports prototype, the digital rear-view mirror will provide a clear view to the rear and thus substantially improve active safety.
"In the past, our drivers had to strictly rely on the outside mirrors when looking rearward," explains says Dr. Wolfgang Ullrich, Head of Audi Motorsport.
The necessarily small size of the mirrors, the shape of the car's rear quarters and the visual impingement of big rear wings, not to mention the vibration inherent in a race car, all combined to severely limit rear vision.
Audi's digital rear-view mirror shows what is happening behind the car on an innovative AMOLED display that is better than any conventional mirror, the company says
A very small and light-weight camera, mounted behind the antennae on the roof of the R18, captures the action at the rear on film and transmits the information to the cockpit as digitalized data.
The view behind the vehicle is shown on a screen that sits in the place where an inside mirror is typically located.
"This gives us a whole host of benefits," stresses Dr. Ullrich. "The operation of the (digital) mirror is weather-neutral. By contrast, when using outside mirrors, heavy water spray severely impairs the driver’s field of vision when it rains. For the new digital mirror, we worked out various day and night driving modes. Even when a rival approaches from the rear with high-beam headlights the image is superb and not just a glaring light spot."
This achievement has been made possible by the latest in diode technology. Instead of conventional light-emitting diodes an active matrix OLED (AMOLED) display is used. AMOLED screens can show multi-colored images and offer better resolution thanks to particularly small pixels with diameters of merely around 0.1 millimeters.
"Even at 330 km/h we’re achieving a totally fluid image flow in real-time transmission," says Ullrich. At this speed, the Audi R18 covers a distance of 92 metres in a second.
As these new types of screens are freely programmable, Audi also uses them to display other data, including the gear that is currently engaged, the slip level of the tires, and some warning lights.
Audi's drivers tried the technology in the recent 24-hours of Spa, in which they finished 1-2-3-4, and were said to be very plesed with it.
"With respect to the screen and the programming we greatly benefited from the work of our colleagues at AUDI AG’s Technical Development (TE)," says Dr. Ullrich. "They helped us move forward with components and knowledge." In fact, in the trial stage, the racers fully relied on an application that originated on the production side of the company. "The system was initially installed in an Audi R8 in which we sent Marcel Fässler and Marco Bonanomi out to test it in road traffic," recalls Dr. Ullrich.
Expanding the role of the rear-view camera in this application could potentially help accelerate its development as a replacement for conventional mirrors in production cars, bringing the idea full-circle.
"If the digital rear-view mirror is introduced in production vehicles at a future time our consumers will yet again profit from a system that has been successfully tested in motorsport as well," says Ullrich.