In part to try out one of the new systems, I cruised up Interstate 87 north of New York City recently in a new Hyundai Equus. When I steered the car to simulate drifting into the lane on my left, a chime sounded. I moved farther into the wrong lane, and my seat belt tugged at me sharply. If I had been drowsy, the system probably would have startled me awake.
In releasing details of a new system of crash tests in October, the National Highway Traffic Safety Administration recommended that car shoppers consider crash avoidance systems such as lane departure and collision warnings as well as electronic stability control, which helps prevent rollovers and is now available on most cars. The Insurance Institute for Highway Safety found from accident data that stability control systems already installed can reduce fatal single-vehicle crashes by nearly half.
The new systems are too recent to have real-world data about their effectiveness. But IIHS analysts estimate that if these and other new technologies became widespread among U.S. vehicles, they might prevent about a third of all fatal crashes. As with electronic stability control, advanced safety features typically have started with luxury models, then moved down to less expensive vehicles. "We expect these new systems to be on many mainstream models within a few years," says Russ Rader of the IIHS.
Here's a closer look at three of the new technologies and what cars offer them, according to data compiled by Edmunds.com.
Lane departure warning Of all the new safety gizmos, IIHS rates this the most likely to reduce fatal accidents. The system monitors lane markers and unusual steering patterns and signals if you are drifting out of your lane. All systems have audible chimes or beeps of some kind. Some brands, including Mercedes-Benz and BMW, use vibrating steering wheels instead of Hyundai's seat belt tug to alert drivers. When you are driving wide awake, the warning can go off annoyingly often for just a minor drift. But in most systems you can turn it off. If you change lanes after putting on your turn signal, the system stays mute.
Lane departure technology is available for 2011 models in the Audi A8 (pictured here) BMW 5 and 7 series and Mercedes-Benz E-Class and S-Class and the Cadillac STS and DTS as well as several Infiniti models. The non-luxury Buick Lucerne also offers a land departure warning system.
Forward collision warning This system uses radar sensors to tell when you are so close to a vehicle ahead and closing so fast that a crash is imminent. A loud signal goes off and the car either activates the brakes slightly (Hyundai) or hits them hard (Mercedes-Benz). This warning usually is integrated with adaptive or "smart" cruise control, which will keep you a fixed distance from the car ahead when activated. I had no inclination to try the collision warning system in the Hyundai Equus. But the smart cruise control noticeably braked the car when another vehicle changed lanes just in front of me.
The Acura MDX SUV, as well as many Audi, Infiniti, Lexus, Mercedes-Benz (E-class pictured at left) and Volvo models offer collision warning. Among non-premium brands, the Ford Taurus, Ford Edge and Explorer SUVs and the Toyota Sienna minivan have the technology.
Adaptive headlights. Though not specifically cited by NHTSA, these headlights, which turn with the steering to illuminate curving roads at night, might help prevent 2,500 fatal crashes a year, according to IIHS. Standard headlights shine straight ahead no matter how you are turning and often illuminate the roadside more than the pavement on winding roads. Adaptive headlights angle to the right or left as you turn the steering wheel to give you a better chance to see a deer or stopped vehicle in the road ahead.
Adaptive headlights are available on many Audi, BMW, Lexus, Mercedes and Volvo models, as well as the Cadillac CTS, the Hyundai Genesis and Equus and three Lincoln models. Among non-luxury brands, Volkswagen offers the technology on its CC, Eos and Golf.
Of course, the best technology can't be as effective as just avoiding driving when you are sleepy. The study by the AAA Foundation for Traffic Safety counsels always getting at least six hours sleep before a long drive, driving at a time when you are normally awake and scheduling a break every two hours or 100 miles.
Photos courtesy of the manufacturers
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