One day all cruise controls will use radar

Posted on June 20th, 2004 in Opinion by Julian Edgar

It’s now a few years since we drove the Alfa 166 – a car that, overall, left us unimpressed. The resulting road test was cutting and the Alfa Romeo distributor in Australia, er, liked it so much that since they read it we haven’t received an Alfa (or Citroen, or Kia – they’re all imported into Australia by the same company) for road testing.

But there was one aspect of the 166 that I was enormously impressed by. What was that, you ask? The navigation system. The VDO Dayton system was the first in-car navigation system that I had experienced and its capability blew me away. No more struggling with a street directory – if in fact you even had the right book in the car in the first place. No more trying to orientate yourself in unfamiliar surroundings. No more swerves when turn-offs were sighted at the last minute. And it worked just as well in the dark as daylight.

In fact I thought the nav system so good that when I moved interstate, one of the first things I bought was a very similar VDO Dayton navigation system for my car… it was fitted to an Audi S4, then when I leased a Lexus LS400, I moved it across.

If you’re not familiar with in-car navigation you could assume from the discussions in the media and on web groups that it is pure wank – no-one, the argument goes, needs one. Unfortunately, that argument most often originates from those who actually have no need of a navigation system in the first place!

One media stunt springs to mind. A magazine decided to have a shootout between people in one car equipped with a street directory, and people in another car featuring nav. I can’t remember which car won the navigational race, but either way, it was a close thing. Therefore, went the story implication, why pay a heap of dollars for a navigation system when you can instead use a $35 book?

Except there were two people in each car, not one person struggling to memorise the street directory… and also drive…

Except the exercise was done in the participants’ home city…

Except, presumably, the person using the street directory was actually good at reading maps…

For me it’s a no-brainer. If you need to navigate an unfamiliar city – especially when on business where being late can cost money – an in-car navigation system is a huge asset.

However, what prompted these thoughts weren’t memories of the Alfa 166. Instead, I’ve just spent a week in Sydney driving a current model 4.2-litre Audi A8. The Audi – like the Alfa 166, another car which overall I consider unimpressive for the (much greater amount of) money being asked – has some excellent gadgets.

As you would expect, its navigation system is far better than the four-year-old VDO Dayton system. There is much more geographical information available – including excellent data like hospital locations – and the system is much faster. Speed is important when you take a wrong turning – the VDO CD-based system can take up to 30 seconds to reorganise the route whereas the Audi DVD system is lightning quick, perhaps taking only a few seconds. When time can mean the difference between getting on a no-exit freeway that is taking you (further) in the wrong direction, or making the turn that leads straight to your destination, route recalculation time is important.

However, while the Audi A8’s nav system was impressive, even better was its cruise control. In fact, in much the same way as the Alfa 166 nav system impacted on my views on car sophistication, so the A8’s cruise control is to me a quantum leap. You see, along with a handful of other expensive cars, the A8 uses a radar-based cruise control.

The way it works is this. Speed selection is available only in 10 km/h increments. So, on a freeway with a 110 km/h speed limit, that’s the speed you set. (This is shown by a highlight next to the appropriate number on the speedo.) However, the system will only allow the car to reach the requested110 if the car in front is travelling at least this fast – and is sufficiently far ahead.

If the car in front drops in speed to less than 110, the Audi will reduce its speed to a matching pace. If the car in front is too close when the cruise control is first engaged, the Audi will slow until an appropriate gap is established. The distance that it leaves can be user set – either actively while on the move or by a default-style menu accessible through the main LCD screen. The between-car distance varies with speed – at slower speeds the Audi creeps up closer.

If the car ahead slows abruptly, the Audi will automatically apply the brakes – and if it is deemed by the system to be an emergency stop, an audible alarm sounds and the driver is expected to brake. A green symbol lights on the instrument display when the car in front is within the minimum safe distance – this changes to red when driver braking is needed.

But describing it all step by step is not really that helpful – basically, all that you need to know is that on the road it works brilliantly.

Suddenly, all that pain-in-the-butt rasing, lowering, lowering, raising, raising of the cruise control speed is gone in one fell swoop. You don’t find yourself inadvertently creeping up on the car in front – a common driving error when speeds are changing only slowly – and safety and convenience are both vastly improved.

A cruise control system makes driving on freeways and main roads less tiring; the addition of radar distance sensing makes it that much less tiring again.

Of course the technology to accurately track the car ahead – including around corners and on multi-laned roads – isn’t simple. And so that’s a good reason why you’ll currently find it only on cars costing AUD$175,000+. But the inevitable trickle-down of the technology will occur – after all, you can now get (as standard equipment) those in-car navigation systems in cars costing less than AUD$50,000.

So I’m happy to go on record and say that in the foreseeable future – say, in 10 years time – all cars with cruise control will have a radar proximity function. It just works so well….

2 Responses to 'One day all cruise controls will use radar'

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  1. . P. Francis said,

    on July 31st, 2007 at 4:29 pm

    I wonder if the time will come when engineers will incorparate a system of detecting speed cameras etc and automatically apply the brakes at the appropiate time ? Interesting thought .

  2. greenmatt said,

    on February 26th, 2009 at 2:12 pm

    Well, we’re there now. The Golf VI has intelligent cruise control for your 35-50k. Feature trickledown seems to be getting faster.