Saab is helping drivers stay focused on the road by developing a safety system that monitors eye and head movements, and sounds a warning buzzer if the driver’s attention strays long enough to risk causing an accident.
At 55mph a car travels 81 feet in just one second - so the consequences of attention lapses, no matter how innocent or brief, can be extremely serious.
The Swedish company, with a world reputation for pursuing safety far beyond the requirements of legislation, is basing its pioneering system 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 system is sophisticated enough to detect when the driver is looking in the rear-view mirror or turning a corner - and will allow more time to elapse before activating the buzzer. The software is also speed-sensitive, so it can distinguish the different conditions in city driving and faster highways.
Infra-red imaging has been chosen as it gives a clear reproduction independent of light conditions. Two cameras are currently fitted to a 9-3 Sport saloon development car, one at the base of the driver's A-pillar and the other in the centre of the fascia.
In commercial production, these mini-lens cameras would be hidden behind the main fascia panelling.
"There's no doubt increasing traffic densities and the growth of in-car 'infotainment' systems are putting an increasing workload on the driver," explains Arne Nåbo, Saab's ergonomics chief.
"The fact is, in everyday driving, we know people actually do take their eyes off the road quite a lot and we are now developing a means of helping drivers to help themselves."
Apart from its primary driving safety function, there are further potential applications for this technology, such as:
- Tiredness warnings. Eyelid, as well as eye, movement can be monitored, allowing the onset of drowsiness to be detected by the frequency and duration of the driver's eyes shutting.
- Automatic in-car settings. All infra-red facial images are unique and it would be quite simple for the 'face-print' of all individuals using a particular car to be memorised. Adjustments could then be made automatically to all seat, steering wheel and mirror settings once the driver is in position. It could even include details such as radio pre-sets and default temperature and airflow distribution settings.
- 'Smart' airbag deployment. In the event of a heavy collision, the speed of the airbag inflation could be fine-tuned to take account of the driver's head position and closeness to the steering wheel at the moment of impact.
"The system is functioning extremely well in our testing," adds Nåbo. "And there is no problem with the hardware, which is reliable and relatively inexpensive. We are now concentrating on fine tuning the timing and nature of the final warning alarm."
Although no decision has been made about putting the system into production, testing and research work at Saab has already demonstrated its feasibility and effectiveness. One day, this technology may be as commonplace in our cars as cruise control or automatic air conditioning.Published 30 December 2004