Yorkregion.com - Wheels - Saab warning system wakes up drowsy drivers
Saab warning system wakes up drowsy drivers
Leisure
Nov 20, 2007 11:12 AM
By: ROBINSON/BEINTEMA AUTOFILES
Saab's Driver Attention Warning System is a development project designed to counter two of the most common causes of road accidents: driver drowsiness and inattention at the wheel.
It alerts the driver by using a combination of text and voice messages, or vibrations in the seat cushion, as soon as the risk of drowsiness or inattention is detected.
Unlike other similar systems, the Driver Attention Warning System does not rely on measuring an erratic change in the steered direction of the vehicle. It is designed to detect the onset of drowsiness or inattention, rather than the immediate consequences.
It utilizes two miniature infrared cameras, one installed at the base of the driver's A-pillar and the other in the centre of the main fascia, which are focused on the driver's eyes.
The image from the cameras is analyzed by software that deploys a series of alerts when the pattern of eye-lid movement indicates the onset of drowsiness, or when the driver is not looking at the road ahead.
The system measures the driver's rate of eye blinking. When the cameras detect a pattern of long duration eye-lid closures, indicating the potential onset of drowsiness, a series of three warnings is initiated.
In the first instance, a chime sounds and a text warning message "Tired" is displayed in the main instrument panel.
If the driver's eye-lid movement does not immediately revert to a normal wide-awake pattern, a speech message "You are tired" is then delivered through the car's audio system.
If there is still no response, a stronger warning tone and the message, "You are dangerously tired. Stop as soon as it is safe to do so" will come over the audio. This can only be cancelled when the driver presses a reset button in the fascia. The system is then immediately reactivated.
The cameras are also able to monitor the driver's eyeball and head movement.
As soon as the driver's gaze moves away from what is defined as the "primary attention zone" the central part of the windscreen in front of the driver, a timer starts counting.
If the driver's eyes and head do not return to the "straight ahead" position within about two seconds, the driver's seat cushion will vibrate. This will stop once the position of the driver's eyes and head are consistent with the vehicle's direction of travel.
The processing of the infra-red image can also detect when the driver retains some peripheral vision of the road ahead, such as while looking in the rear-view mirror, the door mirror or turning a corner, and will consequently allow a slightly longer time to elapse before activating the seat vibration.