Driving dynamics

Fog has settled like a veil over the grounds of the Audi driving experience centre in Neuburg – less than an hour north of Audi’s head quarters in Ingolstadt. Few know this test facility quite as well as Rolf Volland, given his many years as an instructor at the Audi driving experience and his extensive experience as a racing driver.

At the access barrier to the track, Volland brings thae blue Audi SQ8 Sportback e-tron to a brief halt. From here, it’s not far to the driving safety training track and the handling course. A testing ground for everything from Audi’s race cars to large SUVs and everything in between, a different approach is needed when driving an all-electric vehicle.

“When handling electric vehicles, we have almost perfect responsiveness from below and significantly better traction,” Volland explains. The low centre of gravity due to the battery in the underbody makes for very good handling. However, a much more precise and smarter control of the drive is crucial. 

“With two e-motors on the rear axle alone, as installed in the Audi SQ8 Sportback e-tron, there are completely new handling possibilities in terms of driving dynamics.”

Volland demonstrates what this means, accelerating to 90km/h on the first straight, then braking briefly and steering into the tight radius 180-degree turn. 

“There are enormous forces at work,” he says, while at the same time holding the line with almost playful ease. “The wheel on the inside of the turn runs with less torque than the wheel on the outside. Normally, a classic differential would now regulate the different wheel speeds through brake pulses.” But that is not the case with the electric torque vectoring of the all-electric Audi SQ8 Sportback e-tron. In the latest expansion stage of the quattro drive, optimal drive distribution is the key. 

“The torque distribution can be individually adjusted by the two electric motors, each driving a rear wheel,” Volland explains. “The torque is now higher on the wheel on the outside of the turn.” The torque difference is up to 220Nm and at the wheels it is approximately 2100 Newton metres due to the gear ratio, “which in the end means an even more cornering-friendly vehicle,” says Volland.

But torque vectoring is not defined by the three electric motors alone; it is rather their smart interaction. The car now enters the long corner at close to 100 km/h, and Volland tests the traction capabilities of the Audi SQ8 Sportback e-tron. 

“How fast am I going? What’s my steering angle? What is the position of my accelerator pedal? How much grip does the vehicle have? All this results in millions of data that are evaluated in fractions of a second and processed into handling instructions for the three e-motors. And this happens uninterruptedly and continuously.”

The advantages, according to Volland, are not only evident when driving fast around corners but also on the off-road course at the facility. On a section with staggered stone hills, vehicles are made to lean over the transverse axis. As a result, the diagonally opposite wheels hang in the air on the crest of the hill. And that’s exactly where Rolf Volland wants the all-electric SUV to be: 

“At the moment when the front wheel is hanging in the air, there is a braking impulse, and the power is transferred to the other wheel. That’s how the differential works on the front axle. In the rear, on the other hand, it needs no brake intervention. The individual wheels are controlled as needed.” In off-road mode, the electric torque vectoring then also reacts more as needed and more directly than conventional drive systems. “Of course, when it comes to the driving experience, it’s always better when something is driven and not braked,” Volland says, true to his race driver background.

Then there’s the incline with the 55 percent gradient, which showcases another aspect of the vehicle’s performance and how it differs from a ‘traditional’ vehicle in the same situation.

“Electric vehicles don’t have a classic transmission,” says Volland. “When starting up on an incline of 55 percent, you need all the more power on the rear axle and optimum traction of the vehicle.” 

For someone like Volland who has spent so much time in race cars and vehicles powered by internal combustion engines, the different driving dynamics and the technique required are significant.

The vehicle, he explains, not only accelerates faster, drives with less friction and is sportier, but at the same time also offers much more comfort and dynamics in cornering situations. “Highly precise and complex – the way I see it, the triple electric drive and the networking result in a completely new driving experience.” Anyone who thinks that an electric car is not as much fun to drive, he says with a wink and connects the SUV to the charging station, is welcome to book a course at the Audi driving experience and he will happily show them how wrong they are.