A woman driving on Interstate 25 near Denver, Colo., nodded off behind the wheel of her friend's SUV on the morning of Oct. 17.
By the time she was stopped by police, the woman had covered 30 miles in her sleepy stupor. Along the way, she had endangered other motorists by drifting into their lanes and had even swerved in front of an 18-wheeler. The woman said she had slept only two hours the night before, according to an ABC News affiliate that broadcast video footage of the near-tragedy. She was also fighting the flu and was on her way to the doctor when the incident occurred.
To help avert such dangerous mishaps, automakers such as Saab and Volvo are planning to introduce safety systems that would warn drivers about their drowsiness. Drivers won’t even have to realize they are sleepy — their cars will tell them.
While Saab’s system is still being developed, Volvo expects to offer its Driver Alert as an option on several models early in 2008.
Driver inattention, a category that includes drowsiness, contributes to 25 to 30 percent of all vehicle crashes, according to the National Highway Traffic Safety Administration. These percentages might be conservative because they are based on information collected by police at accident scenes, NHTSA says. So drowsiness would be recorded as a contributing factor in the accident only if the driver admits to being tired or if there is an eyewitness account. In fact, a study the NHTSA conducted with the Virginia Tech Transportation Institute in April 2006 indicates that driving while drowsy is a contributing factor in 22 percent to 24 percent of all crashes and near-crashes.
Saab's anti-drowsiness feature is called the Driver Attention Warning System. It uses two miniature infrared cameras — one on the driver's door and one in the center console — to record and analyze eye movement.
If the cameras detect that a driver's eyes have been closed for longer than the length of a normal blink, a chime sounds and the question "Tired?" appears on the instrument panel. If the driver's dozing continues, a second verbal warning announces, "You are tired." A third infraction yields a more severe scolding: "You are dangerously tired! Stop as soon as it is safe to do so!" And anytime the cameras recognize head movement indicating that the driver is focused on something besides what Saab calls the "primary attention zone," the driver’s seat vibrates.
Saab’s Driver Attention Warning System is being tested now in an eight-month trial supervised by the Road and Transport Research Institute in Sweden.
"It is a fact that many drivers do not stop and get out of the car if they are feeling drowsy. So we are now trying to help drivers to help themselves,” Arne Nåbo, head of Saab’s Human Vehicle Integration team, said in a statement.
It will probably take several years for the Driver Attention Warning System to appear on production vehicles, Saab spokesperson Christer Nilsson said. One of the issues Saab is trying to resolve is how to monitor drivers wearing eyeglasses. Thicker lenses and frames "make the system confused," Nilsson said.
But once the system is ready for the road, he said, "from a technical standpoint, it will be possible to install on any Saab." The automaker has not yet set a price for the technology.
Volvo’s system uses different methods to achieve what it hopes will be the same result — alert drivers and fewer roadway mishaps. Its system, called Driver Alert, monitors the distance between the car and the surrounding road markings to determine whether the car is being driven in what the automaker calls a "controlled" fashion. If the driving pattern is thought to be dangerous as a result of driver inattention, an audible alert sounds and a message reading "Driver alert, time for a break" appears on the dash, along with an icon of a steaming coffee cup.
"We looked at eye scanning, and due to problems with accuracy — behaviors and eye shapes being different from person to person — we decided to look into other ways," said Dan Johnston, Volvo’s spokesperson.
Volvo has also developed a Lane Departure Warning system that warns drivers if they cross road markings without a turn signal. Volvo says the system's effectiveness depends in part on the quantity and quality of markings on the road. The Lane Departure Warning system and Driver Alert system will come as part of the same option package on the Volvo S80, V70, and XC70 early in 2008. Pricing for the option package has not been announced.
Another current production vehicle with a feature similar to Saab's Driver Attention Warning System is the flagship Lexus LS sedan. It uses sensors and a face detection camera to sounds an alert if an obstacle is present while the driver's face is not directed towards the road.
Systems that enable cars to monitor their drivers are not new, said Art Spinella, president of CNW Marketing Research in Bandon, Ore. Manufacturers have been working on such systems since the mid-'80s, and “technology is finally catching up,” he said. “They first had perspiration sensors on steering wheels and cameras that watched your face — all sorts of variations — and some are intrusive and pretty annoying."
Spinella's concerns are similar to Volvo's in that he feels that the technology will have to be very flexible in terms of being able to analyze a wide range of faces. "They will have to make it work for everybody, and I think it’s a while coming, still,” he said.
Spinella said that the warnings could be irritating if, instead of simple beeping, they are delivered in an automated voice. He recalled the verbal warnings that once admonished drivers for leaving their doors ajar, which frustrated some motorists to the point that they had the voices silenced by the dealer. Saab and Volvo hope to avoid irking owners by making the technology optional, and furthermore by giving motorists the ability to turn the sensors off.
Audis employ a more subtle, albeit less sophisticated, driver warning system, kindly reminding drivers that they have been on the road for two consecutive hours. However, the warning consists merely of a silent and somewhat cryptic flashing "2:00" message in the dashboard display. There is no indication as to what the car wants the driver to do.