Lane Departure Warning (LDW) Systems
Lane Departure Warning (LDW) systems warn the driver if they unintentionally stray across the lane. Most LDW systems use a forward facing camera mounted inside the windscreen by the rear view mirror to identify the lane markings and determine if they are crossed. Some, Citroën for example, use an array of infra-red sensors mounted underneath the front bumper. Most systems operate at speeds in excess of 40mph and require lane markings to be present.