Whoa there. Forget about the trucker falling asleep. You look like you could use some rest yourself.

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Drowsy Driver Alert Systems

In the opinion of Claes Tingvall, head of the highway traffic safety department in Sweden (the land of Volvo, decades-long leader in car safety), the auto industry is in the throes of a car safety revolution. Safety hasn't been such a priority since the advent of seatbelts in the 1960s [source: Reuters]. Auto companies like Volvo, Saab, Nissan and Mercedes-Benz have been studying sleep-deprived drivers in simulated driving scenarios to find the best way to wake up drowsy drivers.

From these tests, Volvo has created the Driver Alert system. If the car concludes that the driver is drowsing (more on that later), it issues an audible alarm, and an icon depicting a cup of coffee flashes on the instrument panel [source: Edmunds]. Saab has a similar arrangement. The company's Driver Attention Warning System uses a voice alarm: If a driver is nodding off, the car announces "You are tired," followed by "You are dangerously tired! Stop as soon as it is safe to do so!" The driver's seat also vibrates to help rouse him or her [source: Forbes Autos].

Second-generation drowsy driver alert systems will be even more high-tech. Independent companies are perfecting alerts that can safely bring a driver to wakefulness. Additional measures, like emitting puffs of air on the back of a dozing driver's neck, vibrating steering wheels and automatic steering that takes over and gently guides you back into your lane when you drift, may all be found in driver alert systems soon [source: New York Times].

Wait, wait, wait: How can a car tell when you're nodding off? Researchers are tweaking already extant car safety technologies and applying them in new ways. For example, blind-spot warning systems in today's digital cars keep an eye out for other vehicles in places you can't see. They also analyze your car's relation to its lane and whether your turn signal's on or not. Add to this system automatic steering that kicks in when you drift, and you've got part of a drowsy driver alert system.

Soon, you and your car will be better acquainted than ever before. From the moment you first purchase your 2009 Mercedes-Benz and begin driving it, the onboard computer analyzes your particular driving traits to create a profile. It matches this profile against your current driving situation -- like how you're steering, how long you've been driving at a stretch and what time it is. If your behavior doesn't match your profile, the car can tell that something's not quite right and sends you an alert. So whether you're nodding off, distracted or taking chances on the road, the alert should make you more mindful when you're behind the wheel [source: Gizmag]. What's more, the car creates a profile for each driver [source: Motor Authority]. Volvo's system is similar; its cars also analyze how you're driving -- like your proximity to cars ahead of you and whether you're maintaining your lane -- to determine wakefulness.

Saab's onboard computer uses facial recognition software to determine if you're drowsing. Night vision cameras trained on your face analyze slackening facial muscles, your blinking patterns and how long your eyes stay closed between blinks. Once it concludes you're no longer awake, the system kicks in to rouse you from your dangerous slumber [source: Forbes Autos].

But until you buy a new car with one of these systems, you should probably stop for coffee before you nod off.

For more information on high-tech cars and other related topics, visit the next page.

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