Lane Departure Warnning System

Lane Departure Warning (LDWS)

Inattentive drivers that my fall asleep while driving will benefit from a lane departure warning system that uses cameras to monitor both white and yellow lines on highways. When the vehicle crosses over the lines without the use of the turn signal an audible alert goes off warning the driver.

Road-transport terminology: Lane departure warning system (LDW) is a mechanism designed to warn a driver when the vehicle begins to move out of its lane (unless a turn signal is on in that direction) on freeways and arterial roads.

The National Highway Traffic Safety Administration reports that rear-end, lane change and roadway departure crashes account for approximately 3.6 million police-reported crashes each year on United States roadways. The three crash types result in about 27,500 of the Nation’s 42,000 annual traffic fatalities and contribute to a considerable economic loss due to injuries, property damage and decreased productivity.

Lane Departure Warning System - LDWS

http://www.citroen.com/CWW/en-US/TECHNOLOGIES/SECURITY/AFIL/

The Lane Departure Warning System (LDWS) is a new driving aid that detects unintentional lane departures on motorways and dual carriageways at speeds of 80 kph and above.

The system is triggered automatically when the driver mistakenly allows the vehicle to stray out of lane.

The LDWS system works as follows: when the vehicle moves across road markings (white line lane markers) without the indicator being used, infrared sensors behind the front bumper detect the movement and trigger the ECU which warns the driver by means of a vibrating signal on the left or right side of the driver's seat, depending which way the vehicle is drifting. This allows the driver to take immediate action to get back in lane.

The first production LDW system in Europe was the system developed by Iteris for Mercedes Actros commercial trucks. The system debuted in 2000 and is now available on most trucks sold in Europe. In 2002, the Iteris system became available on Freightliner Trucks' trucks in North America. In Japan, Mitsubishi Fuso implemented the system in 2007. In all of these systems, the driver is warned of unintentional lane departures by an audible rumble strip sound generated on the side of the vehicle drifting out of the lane. If a turn signal is used, no warnings are generated.

The first passenger vehicle system available in North America was the system jointly developed by Valeo and Iteris for Nissan Motors and is fitted as an option to their Infiniti FX and Infiniti M vehicles. In this system, a camera mounted in the overhead console above the mirror monitors the lane markings on a roadway. A warning tone is triggered when the vehicle begins to drift over the marking to alert the driver who may, for example, be feeling drowsy or distracted.

In 2008, Infiniti will offer a new version of this feature, which it calls the Lane Departure Prevention (LDP) system. This feature will utilize the vehicle stability control system to help assist the driver in maintaining lane position by applying gentle brake pressure.

In Europe Citroën first offered LDW on their 2005 C4 and C5 models, and now also on their C6. This system uses infrared sensors under the front bumper to monitor lane markings on the road surface. A vibration mechanism in the seat alerts the driver of deviations.

In 2006, Honda launched Lane Keep Assist System (LKAS) in United Kingdom with the Accord. It provides up to 80% of steering torque to keep the car in its lane on the highway. A camera is mounted at the top of the windshield, just above the rear-view mirror. This scans the road ahead in a 40-degree radius, picking up the dotted white lines used to divide lane boundaries on the highway. The computer recognizes that you're locked into a particular lane, monitors how sharp the curve is and uses factors such as yaw and vehicle speed to calculate what steering input is required.

In 2006, Lexus introduced a multi-mode Lane Keep Assist feature which utilizes multiple stereocameras, infrared sensors, along with object and pattern recognition processors. On the Lexus LS, this system allows the vehicle to issue audiovisual warnings and apply corrective steering responses to steer the vehicle back to its lane.