Lane Departure Warning Systems Help Keep Drivers on Track

There are a number of distractions that drivers face while behind the wheel; their cell phone beckons, they spill a beverage or a baby drops a toy, to name a few. Or perhaps they've just been on the road too long and fatigue sets in. Any one of these factors can contribute to a momentary loss of focus on the job at hand - staying in their lane and on the road. Thanks to Lane Departure Warning systems, drivers can be alerted immediately when their vehicle begins to drift out of their intended path. By warning drowsy or distracted drivers when they've wandered out of their lane, Lane Departure Warning systems can help reduce car crashes and save lives.

Lane Departure Warning systems first appeared in production in Europe on commercial trucks in 2000 and are now available on most trucks sold in Europe. Trucks in North America began installing Lane Departure Warning systems in 2002, and today, many upscale passenger cars have a Lane Departure Warning system available.

There are a number of different applications with Lane Departure Warning systems, but all are geared to warning the driver when the vehicle begins to move out of its lane on freeways or surface streets. If the turn signal is engaged, there will be no warning. Lane Departure Warning systems employ a camera that monitors the vehicle's position in relation to the roadway's lane markings. The camera can be mounted in the overhead console above the rearview mirror or within the rearview mirror itself. Other systems use an infrared sensor under the front bumper to monitor the lane markings.

On-board software analyzes the data and, when the vehicle is detected leaving its lane, the driver receives a warning. A number of different warning technologies are currently available. In some models, a simple warning tone is emitted to alert the driver. Another effective warning is an audible rumble strip sound generated on the side where the vehicle is drifting. Some tones are also accompanied by a flashing warning indicator on the vehicle control panel. There is also a warning system using a vibrating steering wheel to alert the driver to unintended departures, and a similar vibration mechanism is available within the driver's seat.

Alcohol and drug use are widely considered to be the main causes of serious accidents involving a single vehicle. But other factors may need to receive significant consideration. A recent study was conducted in Sweden to determine the cause and effect of 38 single vehicle crashes. The results of this study determined that accidents could be grouped into three scenarios: single vehicle crashes caused by driver fatigue, loss of control around curves and driver panic when they lose control and over steer-all conditions that could likely be prevented with a Lane Departure Warning system.

Driver fatigue, in particular, is a major concern. The National Highway Transportation Safety Administration analyzed data from 2002 and concluded about 1,500 fatalities have occurred in recent years from about 100,000 crashes in which driver drowsiness was a factor. Effective Lane Departure Warning systems can help reduce that number. In one test of a number of different Lane Departure Warning systems, the results found steering wheel vibration warning to be the most effective, particularly with drowsy drivers, although all of the warning systems tested cut driver reaction time almost in half.

Some of the highly sophisticated Lane Departure Warning systems are mated with a vehicle's stability control system. Depending on the situation, gentle brake pressure can be applied and/or corrective steering will respond to return the vehicle to its lane.

Vehicle safety has improved considerably in recent decades with the development of driver and passenger airbags, side-impact protection devices, anti-lock braking systems and traction control for improved cornering. Lane Departure Warning systems will take their place alongside these ground-breaking technologies in the vehicle safety realm.