Lane departure warning systems

Long drives, especially on freeways, can be exhausting and hazardous. Thankfully, technology exists to warn drivers if they are drifting out of their lane. Lane departure warning systems have become more common and advanced over the last decade.

Lane departure warning systems have been around since 2000 when they were first installed on trucks in the US and Europe. Since then, the technology has been embraced across the world by trucking companies, and are now available in many passenger vehicles, too.

Lane departure warning systems would be most useful on multi-lane freeways.

What are lane departure warning systems?

There are two basic types of lane departure warning systems. The first, and most common, are systems which warn the driver if the vehicle is leaving its lane (Lane Departure Warning or LDW). For example, an alarm may beep or the steering wheel might vibrate. The other systems warn the driver similarly, but if the car continues to drift out of the lane, the system takes action to keep the vehicle in its lanei. These are referred to as Lane Keeping Systems (LKS). The majority of these technologies rely on video, laser or infrared sensors mounted behind the windshield, which recognise when a line on the road has been crossed. The systems can recognize when a driver is signaling and only activate or intervene if a driver begins to leave their lane without indicatingii.

Lane departure warning systems and your car

For the average motorist, LDW or LKS technology in the family car is rapidly becoming a reality. As early as 2003, the Honda Inspire was fitted with what Honda called a "Lane-Keeping Assist System"iii, and by now the technology is widely available. For example, Ford and Toyota both offer lane keeping technologies as optional extras on some of their most popular modelsiv.

In general, manufacturers offer LDW and LKS as optional add-ons along with other extra safety features like blind spot detection. If you choose to invest in one of the systems, most commonly you'll need to have a front facing camera mounted on your car. However, be aware that a majority of systems will only work properly when you're driving on roads with clear markingsi.

More and more car makers are offering lane departure warning and assist options in their new generations of cars. For example, the Holden Volt includes lane departure warningvi and Volkswagen offers lane assist on a number of modelsvii. Subaru's system is called LaneSway and relies on a camera which can also be used with the company's pre-collision break assist systemviii. The Lane Keeping Assist system from Toyota can work in conjunction with cruise controlix, and Mazda's system warns drivers with an alarm if they begin to drift out of their lanex.

Long drives along freeways and highways, especially at night, can lead to driver fatigue.

How can this technology help?

In Australia, unintentional lane drift is thought to cause approximately 14 per cent of all fatal crashesxii. Testing from the US revealed that lane departure warning systems had a statistically significant effect on the number of lane departures and how long the vehicle left the lane forxi. Drivers were also found to be less likely to make lane changes without signaling.

The technology involved in lane departure warning systems may not be particularly new but it does have the potential to make our roads a safer place.

What are the regulations?

In November 2013, the European Union introduced a regulation stipulating that all new trucks and buses must be fitted with lane departure warning systemsxii. In Australia, there has been some talk of implementing similar regulation for trucks and buses, particularly from the Victorian Transport Associationxiii.

Representatives of the trucking industry in Australia believe that mandating LDW systems here could dramatically lower driver fatigue related accidentsxiii. Driver fatigue is a huge issue for truck drivers, because of the long hours they have to spend on the road. One of the worst possible outcomes of driver fatigue would be a truck drifting out of their lane and into traffic. So far, the Australian Government has not created any clear guidelines which make lane departure warning systems compulsoryxiii.

iHoward B 2013, 'What is lane departure warning, and how does it work?', Extreme Tech, 3 September, viewed 9 May 2014.

iiMazda 2014, LDWS (lane departure warning system), viewed 1 May 2014,

iiiHonda 2003, 'Honda announces a full model change for the Inspire', Honda, 18 June, viewed 15 April 2014,

ivToyota 2014, Lane keeping assist, viewed 15 April 2014,

vFord 2014, Lane keeping system, viewed 15 April 2014,

viHolden 2014, 'Volt: Safety', Holden, viewed 8 May 2014,

viiVolkswagen 2014, Lane Assist, viewed 8 May 2014,

viiiSubaru, Lane Sway & Departure Warning, viewed 9 May 2014,

ixToyota, Lane keeping assist, viewed 9 May 2014,

xMazda, Lane departure warning system, viewed 9 May 2014,

xiMobility Effects Database 2012, Lane departure warning, viewed 15 April 2014,