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Aston’s chassis guru Matt Becker speaks about the DBX

When did the DBX project begin for you?

I had been in the company for about six months in 2015 and was already heavily involved in DB11, but also in the concept stage of DBX. CEO Andy Palmer joined the company in 2014 and in March 2015 the DBX concept was shown.

Aston Martin has no former reference point for developing a car imbued with off road dynamics. Was it a big challenge to start from nothing?

With all the benchmarking, we began to understand the bits we liked about some of our competitors and the bits we didn’t. Bentley, Porsche and Audi all use a common platform so they all have common restrictions of what they can do. We’re in a unique position so we ended up with a bit of an advantage.

How does the dynamic remit of an SUV differ from other models like the Vantage and DB11?

Fundamentally SUVs are very comfortable and agile cars. They can go off road, they can tow a boat and drive around a track. The DBX needs to have equal levels of comfort to a DB11 but actually for the sporting element, when you turn the modes up, it needs to handle like a Vantage so effectively you end up with three or four characters in one car. It needs to be as comfortable as a DB11 but quieter because road noise performance has to be that much better. The development of this Aston Martin DBX is the most complex of my career.

SA has unique road conditions with lots of gravel. How confident are you that the DBX will work on this type of terrain?

When we started the project four years ago we benchmarked a lot of SUVs.  Aston Martin had never built an SUV before and we needed to understand the full range of capabilities needed from this car. This meant that we had to adapt all of our test procedures to make sure we weren’t just developing a GT car. We had to respect the fact that these cars will go off road and will do an amount of gravel driving. It’s not a Discovery in terms of capability but has been thoroughly tested for durability for all road conditions…the type of roads in South Africa as well as more extreme cases.

The DBX is the first Aston to use air suspension. Can we expect it to be carried over to other Aston models?

The platform was designed and developed to include air suspension because we quite quickly realised that there were certain technologies and tools needed on this car to make a 2.4 tonne SUV drive like a sportscar. These include air suspension – to give you a variation of spring rates – and active roll control. The complexity involved means one needs to be aware of the weight penalty, which an SUV can take. At the moment we don’t plan on putting it on any of our other cars.

You’ve been quoted as saying that rear-wheel steering made the DBX’s handling feel unnatural. Can you elaborate on that, as well as how far down the development process you went with it?

I may have been misquoted. We never tried rear steer on the DBX. We evaluated lots of other rivals with rear steer to understand the benefits of manoeuvrability and low speed agility. That said, some of these systems can feel a bit odd at higher speed. Right now, designing a car from a clean sheet of paper, I didn’t want to add to the complexity of rear steer on top of it. From my point of view I don’t like the feeling it gives me.

Are there any AMG-inherited handling components in the DBX? Is the 48-volt architecture part of that, or one of Aston’s own design?

This is Aston’s own design combined with ZF. ZF supply the 48-volt eARC (electronic anti-roll control) system which has nothing to do with Daimler. It has a roll stiffness capability of 1400Nm on the front and 1400Nm on the rear where most of our competitors are 1200Nm front and about 1000Nm rear, so we have the most powerful system on the market. The DBX has less body roll than a Vantage because of the eARC system

You began a career with Lotus where lightweight simplicity is in the design DNA? How counter intuitive does it feel to be leading the dynamics of a SUV with lots of power and comparatively lots of weight? How do you apply that experience into a car as polarising as the DBX?

When I first moved to Aston about five years ago I needed to remind people that I had two positions there; working on Lotus cars but also doing third party engineering where we used to travel all over the world to consult on the dynamics of cars ranging from high horsepower rear wheel drive to lower horsepower, front wheel drive. Actually doing the GT cars was something I was familiar with but also SUVs, albeit more simplistic ones. I’m always looking for the same feeling with any car I do.

Can you carry out this chassis work on modern simulators?

This is the first Aston Martin where we used a driving simulator to prove the concept of the chassis, the steering system and the tyre balance. The great thing about the simulators is you can assess radical changes my simply changing the suspension characteristics on the computer. You can then immediately assess these changes without any design or development costs as it’s all done on the simulator. Through this technology you can prove the concept and make some big decisions and agree targets before you ever cut metal. Of course, you have to ensure that you have confidence in the correlation between simulator and physical vehicle which is why we build an x1 level vehicle (very early mule) to prove correlation. We did this for DBX and had exact correlation.The limitations of a simulator are exposed in assessing ride comfort or looking at the balance between ride comfort and road noise performance.

You’ve been testing at the Nurburgring? What does someone like yourself learn from this track?

AMR has a base at the Nurbrurgring so we spend between 12 and 15 weeks of the year there. We don’t only use the Nurburgring as a track but also as an autobahn because you have to ensure the car has very safe high-speed stability. The reality is that not many people are going to take their SUV around the Nurburgring but we will always test and develop any car there.

Are you going after the Q8 RS’s time?

In terms of laptimes it is something we are considering for the early part of next year, and benchmark against Audi.

If you could apply a percentage to the amount that lifestyle detracts from the sportiness of an SUV, what amount would that be?

I don’t think it really detracts. When we began we never even intended it to be in the same position as a Porsche Cayenne. However when you bring a new chassis, air suspension, eARC system and active centre differential all together you end up with a product that naturally has very good off-road capability. Although we never pushed the off-road envelope we actually ended up with a car that’s as capable as a Porsche Cayenne.

Did you ever test and develop the handling dynamics with a V12 up front?

No.

Andrew Leopold

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