Eye on the road: New devices alert drowsy drivers when it's time to pull off
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Former CMU professor Richard Grace is shown on a TV monitor while testing a DD 850, a dashboard-mounted infrared camera that can detect when a driver is starting to fall asleep. The device will beep to alarm a sleepy driver.
Click photo for larger image.
You know the feeling.
You're driving at night at the end of a long trip, and you're still two hours from home, when suddenly, your eyes begin to droop.
You roll down the window, or bite your lip, or pinch yourself, but it only helps for a moment. Your eyes close again, just for a second (you think), until you jerk back awake.
It's a chronic problem, and a dangerous one.
Federal statistics estimate that drowsiness causes 100,000 accidents a year in the United States, but experts believe the figure is many times that. A study this year by the Virginia Tech Transportation Institute found that drowsiness was the single biggest cause of crashes and near crashes among 100 drivers who were tracked for 18 months.
Preventing those accidents has been Richard Grace's goal for the past eight years.
Dr. Grace, a former Carnegie Mellon University professor, is CEO of Attention Technologies Inc., which just started marketing a Driver Fatigue Monitor -- a dashboard-mounted camera that measures how often a sleepy driver's eyes close at night and then sets off a warning alarm.
Attention Technologies is one of two local companies that have developed anti-drowsiness monitors.
The other is AssistWare Technology Inc., another Carnegie Mellon spinoff that is selling a forward-mounted camera that sets off an alarm when a vehicle veers out of its lane or wanders erratically within the lane.
Dr. Grace said his company is targeting the trucking industry to start with, because drowsiness contributes to one third of all fatal trucking accidents.
An expert in automated sensors, Dr. Grace was approached by the federal Department of Transportation in the 1990s, when he was still at Carnegie Mellon, to develop a device that could accurately measure how often a driver's eyes were closed at night.
It took him nearly a decade of overcoming technical challenges and waiting for the cost of technology to come down before he could produce the $850 monitor he is currently selling.
It works by exploiting the same "red eye" effect that bedevils amateur photographers.
A camera next to the steering wheel sends two alternating bursts of infrared light toward the driver's face. The first pulse is a "red eye" wavelength that reflects off the retina, making the driver's eyes shine brightly for the camera. The second pulse is a wavelength that's absorbed by the water in the eyeball and creates a "dark eyes" image.
The camera's processor can then subtract all the other reflected light from the driver's face and eyeglasses, leaving only two bright dots where his open eyes are.
Ignoring regular blinking, the monitor can then calculate how long the driver's eyes are closed by counting the seconds the bright dots of the eyes disappear from the image.
Once the driver's eyes are closed for 8 to 12 percent of the time, or about 6 seconds out of a minute, the monitor will emit a dual alarm, Dr. Grace said.
It will illuminate a string of lights, one for each second the eyes were closed, and sound a different tone for each second of closure, too.
Road studies have shown that truck drivers often will wait until their eyes are closed 40 percent of the time before forcing themselves to pull over, "which is way too late in the game," he said.
If a truck is going 60 mph on the interstate and the driver closes his eyes for just 4 seconds, he said, the truck will travel more than the length of a football field in that time.
Paul Rau, head of the drowsy driver technology program for the National Highway Traffic Safety Administration, said research also has shown that no matter what kind of alarm is used to rouse a sleepy driver, it will only keep him awake for a short time before he begins to doze off again.
That's why Dr. Grace said his company recommends that drivers pull off the road and take a nap once the monitor sounds.
The best tactic, he said, is to drink a cup of coffee and then take a 20-minute nap. Any longer, and the driver is too groggy when he wakes up from the nap, he said, and 20 minutes is just enough time for the caffeine in the coffee to kick in.
One problem for the Attention Technologies monitor is that when a driver turns his head to look out the side of the cab, the camera can perceive it as closed eyes. So when a driver is in an area with road construction or other distractions, he can set the monitor's time window to five minutes so the alarm doesn't go off as quickly.
The company sold its first monitors to an open-pit mining company in South Africa for use in heavy haulers that take half an hour to get from the mine portal to the edge of the pit.
On Friday, Attention Technologies placed its first large order when Coastal Pacific Xpress Inc. in British Columbia decided to outfit its entire 300-truck fleet with the fatigue monitors, Dr. Grace said.
Mike Formica, CEO of AssistWare, said his company has sold several hundred of their lane-tracking monitors, mostly to trucking companies. The firm markets them as a guard against distraction as well as drowsiness, since a truck can also weave if the driver is dialing a cell phone or picking up something that has rolled onto the floor.
There are at least two other companies that are selling camera technology to attack drowsiness and distraction among drivers.
Seeing Machines, an Australian firm, uses two dashboard cameras to get a depth-perception view of a driver's face during the day, while DriveCam, a San Diego company, uses one camera pointed at the roadway and another pointed at the driver's face.
The DriveCam monitors record images only when there has been a sudden acceleration or deceleration of the vehicle, Dr. Grace said, and were initially sold to monitor aggressive driving in urban vehicle fleets.
In addition, most automobile manufacturers are working on some kind of camera monitoring technology as part of their research efforts, he said.
David Willis, a senior research scientist at the Texas Transportation Institute, said it wouldn't surprise him if camera monitors were standard features in cars someday, and said they might combine the lane tracking and eye closure techniques.
To get the biggest bang for the buck, Dr. Grace added, carmakers may want future cameras to perform multiple functions, such as where to aim the air vents or how to deploy the air bags, based on the body sizes of the driver and passengers.
It's hard to know when camera monitors might become standard equipment, Mr. Willis said, because "in this litigious society, the car manufacturers are scared to death to put something out there that's not bulletproof."
That's why it's easier for now to sell monitors to trucking companies.
The need is more pressing than ever before, Mr. Willis noted, because long-haul truck cabs are more comfortable than ever, increasing the odds of nighttime drowsiness.
In fact, some drivers will let the air out of their special seat suspension systems so the jolting will help keep them awake, he said.
"And that's exactly the wrong thing to do," he said. "You have to get off the road and take a nap."
First Published May 31, 2006 12:00 am