Subaru eyes optical cruise

SUBARU Australia has announced it will offer a locally-adapted optical warning system with adaptive cruise control, automatic emergency braking and lane departure and sway warnings by the end of 2011.

Called EyeSight, the camera-based system was introduced in Japan in 1999 as an adaptive cruise control, but the more sophisticated second-generation introduced in 2008 (and updated with new software in 2009 and 2010) has been the subject of nine months of local testing, with local road signs, faster traffic speeds and shorter traffic gaps accommodated in the software for the Australian market.

The system will be available only in Liberty and Outback, although the Exiga is also equipped with the feature in Japan.

In Japan, the EyeSight option adds about $1200 to a Liberty, but Subaru Australia says it is too early to estimate local pricing.

EyeSight uses two cameras mounted on the headboard either side of the interior rear-vision mirror. The two cameras triangulate position of potential obstacles ahead with a 26 degree angle of camera vision.

The system recognises other vehicles, lane markings, pedestrians and cyclists. It does not work well in detecting animals, or if the screen is obscured by grime or if facing an area without contrast, such as a white wall.

The EyeSight feature that will interest most Liberty and Outback buyers will be the adaptive cruise control, which allows the car to follow traffic automatically up to a pre-determined speed of 144km/h.

Left: Objects such as pedestrians can be detected by Subaru's EyeSight system. Below: Twin cameras either side of the rear-view mirror are the key to EyeSight.

The adaptive cruise is set-up by the driver with a choice of three set distances and a maximum set speed adjustable in 5km/h increments.

Provided the cruise control has been set at a speed above 40km/h, the system will allow the vehicle to drop to a lower speed – even to a standstill – and still operate.

As long as the speed difference between an EyeSight Subaru and the car head is no more than 30km/h, the Subaru will adjust its speed to whatever speed the lead car is doing, and at one of three predetermined distances chosen by the driver.

When the vehicle in front stops, the EyeSight Subaru also stops, at a target distance of four metres.

Assuming that the vehicle ahead moves away before the Subaru is stopped for three seconds, the Subaru will follow automatically. If more than three seconds elapses, the system will beep when it senses the car ahead has moved away and the driver will need to nudge the accelerator to reactivate the system.

This feature is likely to be a boon for daily freeway commuters in major cities, where the hard work of driving in stop-start traffic will be alleviated.

The crash avoidance component of the system recognises an obstacle and stops the vehicle if the system senses the driver is not reacting to it.

The system works most effectively in urban environments where it is more likely that Eyesight’s upper limit of stationary object detection – 50km/h, with no luggage or passengers on board – will not be exceeded.

Even then Subaru says that the EyeSight-equipped vehicle will nudge the object ahead, but claims damage at this speed will most likely be minimal. When approaching a stationary object at more than 50km/h, the system cannot react quickly enough to stop before thumping into it.

Up the 30km/h, if EyeSight detects that the driver has not applied the brakes in time, it will active the brakes in an emergency stop and even with a full load of passengers and cargo, it will stop before hitting the obstruction.

Although Eyesight will stop the vehicle before hitting a stationary object at speeds up to 30km/h, it will also decelerate in pre-crash emergency braking at speeds of up to 144km/h – provided the speed difference between it and the vehicle ahead is no more than 30km/h.

This applies when a vehicle cuts in from another lane and then begins to brake.

Other safety features include lane marking recognition, which will sound an alert if the driver has moved over the lane markings without signalling, and also emit a warning sound if the vehicle is swaying in a pattern typical of driver fatigue.

Subaru says the system recognises if the driver has selected Drive and begins to accelerate into an object (such as can occur with ‘unintended acceleration’, when a driver mistakenly selects a forward gear instead of reverse, or presses the accelerator instead of the brake) and reduces the throttle opening.

Subaru gave the media an opportunity to try out the Eyesight system this week in a Subaru Outback that has been used as the test mule for local calibration for nine months.

The system was tested in a variety of situations, including towing a caravan hitched up and on dirt roads – both activities, incidentally, that Subaru says it would not recommend for EyeSight.

GoAuto drove the Outback behind a Tribeca on a closed race circuit with the cruise control set to 60km/h, and the only driver input was steering. Our foot hovered over the brake pedal more than once, but I was assured by the accompanying Subaru engineer that if we hit the brakes that the system would cancel.

Unless you’re completely unaware of your surroundings, you will instinctively jump on the brakes when you realise you’re going to crash. Depending on at what point pre-crash that occurs, from what Subaru says, EyeSight might or might not help you out as it has been engineered to allow the driver full control.