Checks are being carried out on a vast array of test beds, on Volkswagen Group proving grounds, at minus 35 degrees Celsius inside the Polar Circle, in the scorching desert heat of Southern Africa, on the highways of Florida, on dust, grit and gravel in Europe, Asia, Brazil and Central America, through to the gruelling Nordschleife of Germany's Nürburgring. But this is not all. The Q7 is also being put through its paces on lonely, winding country roads, on autobahns and in the midst of heavy city traffic in congested urban areas. For over two years now, disguised Q7s have been out and about on public roads, as well as in the most remote corners of the earth, under extreme dynamic, climatic and topographic conditions.
Van Meel identifies the reasoning behind this test of automotive toughness, "An SUV has to be able to perform on the road as well as off of it, and to meet stringent customer expectations. Our comprehensive test program, which is unique in its extensiveness, guarantees that the Q7 will fulfil the very highest expectations in terms of reliability, durability, robustness, stamina, speed, handling, comfort, flexibility and everyday usability."
In order to meet these targets, Audi engineers and test drivers are hard on their vehicles. Representatives of Audi Vehicle Development are pulled from all possible disciplines, such as chassis, driving dynamics, power units, transmission, electronics, bodywork, total vehicle and quality assurance.
The durability testing chief affords a glimpse into the test catalogue, "The test tracks we use are a collection of the world's worst driving and obstacle routes imaginable in customer operating scenarios - pot holes, rough cobblestones, speed bumps, undulations, grit, non-surfaced roads, gravel, rough rock trails, railway crossings, water obstacles. These are highly dynamic courses, on which driveline, body torsion and bending, as well as running gear durability and functionality are tested." says Brand. In addition to that, the Q7 has to prove itself as a towing vehicle. If the vehicle withstands all this, then it will also take anything the customer can throw at it. One comparative figure supports the severity of these tests - 8,000 kilometres run on this test cycle is equivalent to 300,000 kilometres of normal everyday use.
On top of all this, the engineers from Corrosion Protection Development also have their turn with the Q7. In Audi's Corrosion Protection Centre, prototypes undergo the so-called INKA test (Ingolstädter Korrosions- und Alterungstest, Ingolstadt Corrosion and Ageing Test). This simulates a 12 year vehicle life within just six months. Hydropulse equipment pummels the vehicle under ice cold conditions, after which it is exposed to extreme sunshine in a climate chamber. The Q7 must then withstand hours of salt water spray in a salt spray chamber. Drives through pits of mud and salt water, as well as stone chip tests on gravel tracks, also seek out every last weakness that could possibly be an entry point for rust.
The off-road handling of the Q7 is tested on a special off-road track. The focus of this particular program is on the degree of axle articulation, as well as on handling on steep inclines and in deep water.
A special dust track in southern Europe is the location for checking cabin sealing. Furthermore, the interior of the closed vehicle must withstand extreme temperatures over a period of months in the scorching desert sun in order to test the quality of the materials utilised inside the cabin.
What goes for sealing against dust, must also, of course, apply to water. A test chamber in Ingolstadt is designed specifically for this purpose. It enables vehicle developers to specify precipitation ranging from a light shower to a tropical monsoon. The vehicle can also be inclined by up to 30 degrees in order to identify any points through which water can find entry into the cabin.
A test hill facilitates checks on pulling away with and without a trailer on inclines of up to 35 percent, while the driveline is put through a host of high speed tests on the speed track.
Speaking of high speed, the Q7 has to prove itself on the world's toughest race track - the Nürburgring's Nordschleife. This is where Audi handling engineers, mechanics and supplier representatives spend 13 to 14 weeks a year pushing the SUV to its limits. The 20.8 kilometre Nordschleife, with its 33 left and 40 right bends, offers the best possible route profile for optimising handling (running gear, steering, wheels, tyres, shock absorbers, springs and bearings) and braking, as well as vehicle comfort characteristics in extreme situations. It is also perfect for fine tuning the Q7's sporting character. In so doing, the test vehicles rack up almost 250 laps, or around 5,000 kilometres, on legendary track sections such as the "Caracciola-Karussell", the "Brünnchen" and the "Planzgarten".
An equally important element of test driving is the general testing. This covers the functional verification of all the Q7's electronic features - from engine and transmission electronics, park assist and reversing camera, through to the lighting on the vanity mirror in the sun visor.
In so doing, all functions are put under the microscope in the most diverse operating conditions. The drivers are largely on the road at night, in order that the team is able to analyse test results during the day.
They are tasked to match tests as closely as possible with real customer situations. This is why, although they receive certain instructions on which items and functions are to be tested in one shift, the "how" is left largely up to them. The options for completing the questionnaires are similarly individual. One element of the checklists is, incidentally, "stress tests". Examples of this include the repeated activation and deactivation of electronic systems while stationary and driving, untypical usage such as windscreen wiper operation when it's not raining, parallel operation of the vehicle by both driver and passenger, simultaneous operation of multiple applications, or simply checking system reaction to a CD being inserted into the slot upside down.
The majority of these test drives, including all stress tests, are carried out on the Audi proving grounds close to Ingolstadt. The program also includes, however, evaluation drives on public roads, with preferred test areas being centres of urban population. These locations are often subject to the effects of extensive radio interference and highly concentrated mobile communication networks. These evaluations help to establish whether such disruptive signals have a negative effect on vehicle electronics.
In the course of all these tests, the customer remains the focal point. Testing any vehicle demands that market and customer-specific issues be addressed. Legal requirements, infrastructure such as filling nozzles at fuel stations, fuel quality and customer habits vary from country to country. Nevertheless all these demands must be met.
Heike Biebl-Walther heads up testing for North America at Audi. "Vehicle requirements vary a great deal across the different markets," she says. "That is why it is important to take these requirements into account at an early stage in the vehicle development process." The US market will be one of the most important sales regions for the Q7. Therefore, the vehicle has also been, and is still being, tested intensively there.
Everyday vehicle functionality across diverse operating circumstances is of fundamental importance to customers. It is for this reason that a great deal of worth is put on intuitive operating logic, appealing haptic and ergonomic handling, such as the ease of folding and erecting the third row of seats.
The scope of an SUV's service is extremely broad, extending from the short off-road stretch to reach the weekend cabin in the Apalachian Mountains on the east coast, all the way to a beach holiday on California's Venice Beach. There are also an increasing number of American women who are attracted to this particular class of vehicle. They use it to take the kids to school or to make the short trip to the shopping centre.
Biebl-Walther offers one example of typical American driving habits. "Many Americans spend considerably more time in their vehicles than us Europeans," she explains. "In the case of long commutes, for example, it's quite normal to eat breakfast in your car. For this reason, features such as storage facilities, power outlets or cup holders take on a whole new significance for the driver. In the Q7, these requirements have been comprehensively addressed."
A further example of the diversity of customer requirements is the value put on vehicle infotainment by those who frequently make long-distance journeys in the USA with the Q7. Alongside the FM signal common in Germany, customers in the USA and Canada also use medium wave and satellite radio. "While satellite radio has, so far, not been available in Europe, this technology is already standard in the USA," says Biebl-Walther. "We are carrying out customer simulation tests on these systems throughout North America, for function, ease of use and quality of reception."
Driver selection is particularly important in simulating the customer as closely as possible. "Average" American drivers are the order of the day. These test drivers must complete questionnaires and be prepared to have their driving profiles logged on board the vehicles, and data streams from measuring devices recorded. These data are later evaluated against the broadest possible criteria.
Across the USA from east to west, Audi Q7 models are continuously being put through this sort of testing in order to ensure that they also function perfectly in customer hands, be it in scorching heat, freezing cold, choking dust and equally choking traffic.
In parallel with the development process, the USA is also host to regular sign-off drives, on which the Board of Directors and top management of AUDI AG put the vehicles through a comprehensive check-up. On one occasion this actually included taking the Q7 through its paces on the 4,300 metre high Pikes Peak. It was this very mountain that inspired the name of the Audi concept car, which signalled the start of the Q7 at the 2003 Detroit Motor Show.
(August 2, 2005)