What is lane keep assist?

Many modern vehicles have evolved from simply warning the driver that the vehicle is wandering out of its lane – with a Lane Departure Warning system – to proactively taking control and assisting with keeping the vehicle in its lane.

Named Lane Keep Assist, the system was pioneered by Mercedes-Benz, using a camera array linked to the brakes. If that system detected the vehicle was veering out of its lane, it braked the appropriate wheel to slow that side of the vehicle and nudge it safely back into line.

The widespread adoption of electric power steering means most Lane Keep Assist is now operated via the vehicle steering. Different brands use different systems, some with adjustable sensitivity to road markings and adjustable strength to the steering intervention.

Victoria’s Transport Accident Commission describes LKA (Lane Keep Assist) as one of the most important technologies to help prevent crashes and one that is “extremely beneficial in preventing trauma”.

“There’s a huge amount of trauma that occurs on our high-speed regional roads, particularly when vehicles leave the lane,” says Dr David Young, the TAC’s Manager Vehicle Safety, Innovation and Technology.

“Lane keep assist is one of the primary systems that’s built to help us reduce that trauma.”

Many manufacturers advise against relying on lane keep assist on poorly-marked or twisty roads, such as those commonplace in Australia, and most systems can be disabled by the driver. The system will also note when the driver is using the indicators to merge and won't steer the vehicle back into the lane in that situation.

Despite some misunderstanding that LKA or lane-centering technology can act as a semi-automated system, the technology still requires the driver to be in complete control of the vehicle, warning the driver against taking their hands off the wheel.

But while Lane Keep Assist will always require an alert driver the performance of the technology is constantly improving, something Dr Young says promises to improve its usefulness.

“As with all technology it’s always evolving,” he says.

“And Lane Keep Assist’s ability … we hope will always improve into the future as better cameras or better sensors come on board or more advanced computing is possible.”