Lane Keeping Assist Systems Explained

This brings us to one of the newest active safety technologies that have started to be implemented by most car makers out there: Lane Keeping Assist.

Whether it's called like that, or it's titled "Lane Assist", "Lane Departure Warning System," "Whoa there!" or something other than that, pretty much all similar systems are designed for a single purpose: to keep your car going in the safest direction.

Over the years, during the evolution of the automobile, a lot of accidents have happened not because of speeding, drinking, technical problems or plain stupidity, but because of tiredness.

Usually, long distance drivers who become tired may experience situations like this – when they nod off for a second while behind the wheel and the car drifts from its lane towards a bridge's end or into oncoming traffic.

Most traffic fatalities on high-speed roads during perfect weather happen because a driver has simply fallen asleep for a second, during which time all hell broke loose. To minimize these types of most likely fatal accidents, certain car manufacturers have introduced technologies which can either try or prevent them altogether.

The way each of these systems works depends on some factors, like the price of the car they're fitted on or the actual procedure which they follow to do their designated job.

The cheaper ones usually just try to warn the driver if their vehicle is leaving its lane unintentionally, by ways of visual, audible, and/or vibration warnings.

The ones fitted on more premium/expensive cars, beside the warnings, can also take preemptive measures without the driver's input. Yes, they can actually make you the witness to a poltergeist experience even in a non-autonomous vehicle.

The first production lane keeping assist system debuted on the Mercedes-Benz Actros commercial truck in Europe, in the late 1990s. In this case, the driver was warned of unintentional lane departures with the help of an audible that could be heard on the side of the vehicle drifting out of the lane.

Naturally, for the system not to become utterly annoying each time the driver was switching lanes if the correct turn signal was used, no warnings were generated.

In the early 2000s, some car manufacturers began introducing similar technologies on their models, from Citroen to Nissan, Honda, Toyota or BMW. Let's take a look at how some of them work:

In some Nissan/Infiniti models, an onboard camera continuously monitors the lane markings on the road. If an unintended lane departure is observed, the system triggers a warning and/or gently applies brake pressure to the right or left wheels, according to which direction the vehicles is heading. It tries to both warn the driver and correct the vehicle's direction;

Some Toyota and Lexus vehicles use a stereo camera system to monitor the lane markings on the road, thus having a better chance of observing if the car is drifting out of its lane. In case that happens, the electric steering pump will counter-steer the vehicle back onto its lane. It tries to both warn the driver and correct the vehicle's direction;

In modern Citroens, Peugeots and DS cars, the lane assist system is not that intrusive, and it monitors the lane markings on the road via infrared sensors. If an unintended lane departure is acknowledged, it will use a special vibration mechanism built into the seat to alert the driver. It only warns the driver without trying to correct the vehicle's direction;

At Mercedes-Benz, the newest generation of the lane keeping assist system is sort of a cross between the one found on certain Nissan/Infiniti models and Citroen.

Using cameras to monitor the road markings, if the above-mentioned lane departure scenario happens it will first trigger a vibration mechanism built into the steering pump so it will vibrate the steering wheel, issue a visual and audible warning.

If that doesn't work, it will gently brake the wheels on the opposite side so as to correct the vehicle's direction automatically.

All in all, as you can all imagine, neither of these systems is foolproof. They do help, a lot, in taking care of the direction you're going, but they're not all-knowledgeable. This technically means that having a car that can steer itself back into the driving lane, automatically brake and/or accelerate, doesn't mean that you can just set a course like Jean-Luc Picard and take a nap while going a hundred miles an hour on the autobahn. Keep your eyes open and drive safe!