New Saab Safety System helps drivers pay attention
from Automotive (1558 articles)
New Saab Safety System helps drivers pay attention
January 5 2005 Good news for the sleep deprived and sufferers of Narcolepsy. Saab is developing a safety system that monitors eye and head movements, issuing a warning signal if the attention of the driver strays long enough to risk causing an accident. "The other car appeared from nowhere! I just didn't see it." Drivers often make such comments after an accident or a near-miss. In truth, it is an admission that for a brief moment the driver was not concentrating fully on what was happening outside the car.
It's an experience behind the wheel that most of us would admit to having at one time or another. It is understandable because drivers can sometimes have their attention momentarily distracted for a whole number of reasons. It could be a case of searching around for that favorite CD; looking at an advertising billboard a little too long; 'rubber necking' while passing the scene of an accident, or trying to find a street sign along an unfamiliar road.
Taking into account vehicle speeds - at 100 km/h, a car travels 26.6 meters in just one second - the consequences of such lapses, no matter how innocent or brief, can be extremely serious.
Saab is now pioneering a unique driver attention warning system that is designed to overcome the hazard of driver distraction. It is based on what the driver actually does behind the wheel, instead of what he or she should be doing.
Two miniature cameras with infra-red lenses are installed in the car to monitor the driver's eye and head movement. As soon as the driver's gaze moves away from what Saab calls 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, a buzzer will sound. And if there is still no response, a brake pulse will be delivered through the car's ESP system.
The measurement and processing of the infra-red image includes the relationship between eye gaze direction and head movement. It is sufficiently accurate to detect when the driver retains some peripheral vision of the road ahead - such as while looking in the rear-view mirror or turning a corner - and will consequently allow a slightly longer time to elapse before activating the warning buzzer.
The software is speed-sensitive. In this way, the system can distinguish between a busy, city driving environment and more open highway driving at faster speeds.
In low-speed, as in city driving, there is a wide driver attention zone, allowing for plenty of head movement but a shorter time 'buffer', before the warning buzzer is triggered. High-speed mode will revert to a narrower attention zone and a longer time buffer due to reduced traffic densities.
To further distinguish between prevailing traffic conditions, the warning system could also be linked to the satellite navigation system. The buffer time zone would then, for example, go to a short zero tolerance setting when the car is near a school or a hospital.
