When Land Rover wants to reveal its latest engineering and technology, it invariably does so in extreme driving conditions; conditions that reflect its rigorous test programs.
For the new all-wheel-drive Discovery Sport (see http://articles.sae.org/13602/), it chose Iceland, unpaved mountain roads, and (although it claimed no control over the environment), a 100-km/h (62-mph) whiteout blizzard with minimal visibility, the rear lights of the car in a “buddy-buddy” convoy just a few meters ahead often totally obscured and at times impossible to follow. With the urgent need on tight corners to peer intensively around the A-pillars, any aid to visibility would have been welcome as the car’s tires, with a total of 800 studs, struggled for grip.
So it was not wholly a coincidence that as the testing Icelandic challenge progressed, Jaguar Land Rover (JLR) revealed that it is now focused on a radical visibility enhancement research program that, if successful, will create what it calls “Follow-me Ghost Navigation” projecting a head-up virtual image of a car ahead for the driver to follow, and even more radically, “see-through” A-pillars using the interior of the pillars as screens to present a real-time video of the normally blanked scene.
Dr. Wolfgang Epple, JLR Director of Research and Technology, wants to see, quite literally, 360° visibility in all the company’s vehicles, with the A-pillar system extrapolated to B- and C-pillars: “If we can keep the drivers’ eyes on the road ahead and present information in a non-distracting way, we can help them make better decisions in the most demanding and congested driving environments.”
He explained that a screen would be embedded in the surface of each pillar inside the car, taking a live video feed from cameras covering every angle outside the vehicle to compensate for normal pillar blind spots.
The system would also be linked to driver head movements or use of the turn indicator to trigger pillar images. Other solutions to A-pillar blocking have been considered by automakers, including Volvo's open girder concept.
In effect, the JLR system would create a 360° virtual windshield and would also have a link to the Cloud, enabling it in an urban area to present, in HUD form, information such as parking space availability or gas station prices.
Because they are camera-based, the systems involved might be struggling in the Arctic conditions in Iceland, which had the windshield wipers building up ice layers despite the permanent use of windshield heating. Heated wiper blades might be another R&D path to consider.
The decision to use Iceland, with its highly unpredictable weather patterns (temperate through near-Arctic) in mid-winter, was unusual for any motor manufacturer, although Volkswagen and Mercedes-Benz have used it in more clement seasons.
But it is the sort of extreme weather experienced that is the stuff of SUV testing, and Iceland delivered a soupçon of this to Automotive Engineering editors who were invited by the company to drive production examples of the new seven-seat Discovery Sport.
Although “testing” is the word that links every aspect of vehicle creation and development, it may also be the least appreciated. It is very easy for a manufacturer to reel off thermal, topographical, distance, and a host of other facts and figures about the rigors—virtual and real—to which their latest products have been subjected, but it can be difficult to realize exactly what all this means. The very tough Iceland experience achieved that.
The Discovery Sport is based extensively on Evoque architecture, but with some significant differences, notably the use of fully independent integral multi-link rear suspension, a necessary configuration to facilitate the fitment and stowage of a third pair of seats that can fold into the floor.
Packaging was a major criterion of the design, says Program Director Paul Cleaver: “Overall length was really important; we wanted to create a compact SUV at sub-4.6 m (the production car measures 4590 mm). Everything else in the segment with an extra row of seats was over that length. The decision was pivotal in the way we engineered the back end. The Discovery Sport had to be a wheel-at-each-corner, short overhangs, and compact stance solution.”
The compact multi-link rear axle was essential. As well as its dimensions, its pluses include on-road agility, claimed class-leading wheel travel and axle articulation at 340 mm (13.4 in), and required levels of on and off-road composure. Its use contributes to reduced road noise entering the cabin. Because the suspension turrets make only a minimal intrusion into the luggage area, they allow row-two seating to slide and recline past the turrets for maximum leg-room.
The lower control arm and rear suspension knuckle are produced from thin-walled hollow aluminum castings. The rear suspension is mounted on a steel subframe, which is light and stiff to promote improved steering response.
Another significant technology aspect of the Discovery Sport is the incorporation of a pedestrian airbag triggered by pressure-tube sensors mounted between bumper cover and beam, which is designed to detect impacts with adult pedestrians. Should any impacts be detected between 24 and 48 km/h (15 and 30 mph), an airbag concealed by a small scuttle panel at the base of the windscreen deploys in no more than 60 ms, drastically reducing the risk of serious pedestrian injury, explained Cleaver.
The scuttle cover is attached to the airbag using two tethers and forms part of the airbag system in helping to spread the load evenly across the airbag, avoiding obscuration of the driver’s vision during deployment and reducing airbag volume to 110 L (3.9 ft³). Rigorous testing ensured that it would not deploy in extreme off-road situations, added Cleaver: “The innovative pedestrian-protection system is not only unique in the SUV class, it’s also yet to debut in most other segments.” The new Land Rover has achieved a 5-star EuroNCAP safety rating.
The Discovery sport comes with a choice of six-speed manual or nine-speed ZF automatic transmission. It has very comprehensive electronic chassis support systems and uses a Haldex Generation 5 system, but does not have a low ratio transfer box
Would that have helped in the exceptionally challenging conditions in Iceland experienced by Automotive Engineering? Possibly. But Land Rover’s support teams were on hand with Defenders to pull any errant vehicles back into line, another—albeit low priority—aspect of vehicle testing: ensuring that the media survive.
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