► Intelligent Speed Limiter constantly adapts to traffic signs
► Will debut in new Ford S-Max in summer 2015
► Another step along the path to autonomous driving?
The concept of speed limiters is a familiar one. The majority of new cars on sale today are available with just such a system; operated in a similar way to cruise control, the driver sets a speed – 70mph, for example – and is prevented from exceeding it as the car automatically backs the power off and maintains a speed as close to the pre-set figure as possible.
In practise it feels a bit like driving into treacle – a sort of squashy, virtual speed barrier that you can’t quite drive through.
This is the next step. Ford has announced a new system it calls Intelligent Speed Limiter, which continually resets the limiter every time the speed limit zone changes. In theory, the company says, you’ll never face a speeding ticket again.
How does Ford’s Intelligent Speed Limiter work?
It’s linked to a camera in the upper part of the windscreen which can recognise and detect traffic signs. That in itself isn’t new; in existing Fords, and cars from other manufacturers, the signs are displayed as reminders on the instrument panel.
In this case, the camera recognition is linked to the speed limiter, and continually adjusts the maximum speed according to each sign it sees.
When the limit lifts, it allows the driver to accelerate up to the new speed. Likewise, should the limit changes to a lower speed it’ll slow the car automatically. It does this not via the brakes, but rather by limiting the amount of fuel supplied to the engine – so no brake lights to confuse drivers following on the motorway. Of course, if the car’s heading downhill there’s only so much the system can do, so an alarm is sounded if the speed limit’s exceeded.
The Intelligent Speed Limiter system can be put to work between speeds of 20mph to 120mph, and it’s linked to the sat-nav, so if you’re travelling for long distances between traffic signs it can use the map data to make sure the car’s keeping to the appropriate speed limit. It works abroad, too.
And if you get fed up, you can override the system with a firm press on the throttle pedal.
When does the system go on sale?
First Ford to get the system will be the new S-Max, on sale in summer 2015. It’ll be operated in the same way as a conventional speed limiter system, using controls on the steering wheel.
Where does this technology go next?
Next step will be linking the system to the cruise control, so that cars can maintain their own speed without any need for the driver to do anything as arduous as pressing a pedal. Tesla is one manufacturer already said to be some way down the line in this field.
We’re on an inexorable path to autonomous driving; this is the latest small, but inevitable, step.