Electronic Stability ControlClick to enlarge picture

Also known as ESC, electronic stability control helps the driver maintain control of the vehicle by preventing it from sliding or skidding.

In a 2006 survey of 500 consumers conducted by Accenture, more than two-thirds of respondents ranked safety as the most important technology to have in their automobiles, and seven out of 10 were willing to pay extra for safety features. Accenture is the largest consulting firm in the world and is one of the largest computer sciences and software companies on the Fortune Global 500 list.

Safety technology has experienced a quantum leap in the last few years, with advances spurred by the government in an effort to lessen loss of life and injury, as well as automakers seeking a competitive edge. But it's equally driven by consumer awareness.

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"Auto safety took a big step forward in the '90s, when there was a high awareness of ABS brakes and airbags," notes Charlie Vogelhiem, vice president, automotive development, with J.D. Power and Associates. "We saw that when people had a vehicle that didn't have airbags, for example, they were less inclined to keep it."

Below we highlight the top 21 auto-safety technologies currently available, ranging from the common to the cutting-edge. And if auto-safety tech follows the typical pattern, even innovative features currently found only on higher-end cars should trickle down to more affordable automobiles. "As consumers replace their existing vehicles and the technology price tag continues to decline," explains Accenture's Richard Spitzer, "[safety features] will be part of the deciding factor in the car purchase decision."

Pre-Collision Systems

This technology uses various methods to sense and prepare for a collision. When a sensor signals an impending crash, the system takes preemptive action such as pre-tensioning the seat belts, preloading the brakes and even aligning airbags to better protect occupants.

Electronic Stability Control

To help drivers maintain control, ESC compares steering and braking inputs with the car's lateral acceleration, rotation and individual wheel speeds. If a difference in the driver's intended path and that of the car is detected, brakes can be automatically applied and the throttle can be dialed back until the vehicle is back on track.

Brake Assist

This technology resulted from a study that determined that most drivers do not push the brake pedal hard enough in emergency situations. So when sensors detect "panic" braking, Brake Assist applies maximum brake boost and therefore decreases stopping distance.

Dynamic Head Restraints

Few people adjust their car's headrests properly to prevent whiplash, so some vehicles now come with active head restraints that move into more effective positions when a car is rear-ended. Volvo's Whiplash Protection System (WHIPS) and Saab's Active Head Restraint (SAHR) go a step further by getting the seats to help in mitigating whiplash injuries.

Dual-Stage Airbags

The National Highway Traffic Safety Administration (NHTSA) stipulated that all passenger cars and light trucks produced after September 2006 must include passenger-side front airbags that are automatically enabled or disabled depending on whether a front passenger is detected (typically by seat sensors), and some now deploy in stages depending on the severity of a crash or the weight of the front-seat passenger.

Side and Supplemental Airbags

Side airbags can greatly reduce injuries, since occupants are often more vulnerable than in front- or rear-end crashes, where there's more of a "crumple" zone to protect them. Side airbags are not mandated by the NHTSA, however, and auto manufacturers can decide where and how to deploy them, and whether they're a standard or optional feature. Some luxury cars also include supplemental airbags, such as with BMW's Active Knee Protection and Head Protection systems.

Blind Spot Warning Indication

The Volvo S80's Blind Spot Information System (BLIS) uses a camera on each side-view mirror to scan a driver's no-see zone and indicators in the corners of the front windows alert the driver to the presence of vehicles. The Side Assist in the Audi Q7 and Side Blind Zone Alert in the 2008 Buick Lucerne and Cadillac DTS and STS work in much the same fashion, except the indicators are located on the side-view mirrors, and GM's system use radar instead of cameras.

Lane Departure Warning System

Infiniti's Lane Departure Warning (LDW) System uses a camera in the rearview mirror to detect when the vehicle gets close to the lane marker and sounds an audible warning. GM will also offer the technology on the 2008 Cadillac DTS and STS, and Buick Lucerne.

Night-Vision Camera System

Hitting an animal or pedestrian while driving after dark is an accident night-vision cameras can help prevent. BMW's night-vision system senses thermal energy and Mercedes' projects infrared light in front of the vehicle, and both show night-vision images on a screen in the dash.

Adaptive Headlights

This technology directs light from the headlights in the direction that the steering wheel is turned, to help illuminate where the driver intends the car to go. A feature currently found only on higher-end cars, adaptive headlights will likely trickle down to more affordable vehicles.

Tire-Pressure Monitor

Starting in the 2008 model year, the Feds will require all new vehicles to include tire-pressure-monitoring systems, which use sensors to provide information on tire inflation to a display in the instrument panel. Vehicles ranging from sports cars to SUVs already allow drivers to check tire pressure on the fly, and some show pressure in individual tires.

Rollover Protection

Manufacturers first offered airbag systems that inflate from the headliner or ceiling in top-heavy SUVs to protect occupants in case of a rollover. Ford's Safety Canopy, for example, covers 65 percent of the window surface in the first two rows of seats in Ford, Mercury and Lincoln SUVs, and the system is also available on the Volvo and Land Rover SUVs, as well as on the Ford Freestyle, Five Hundred, Mercury Montego and the Volvo C70 convertible.

Head-Up Display

Looking away from the road for even a few seconds can be dangerous. By projecting vital information from the speedometer, tach or navigation system on the windshield, a head-up display (HUD) allows drivers to keep their eyes straight ahead.

Bluetooth Hands-Free Phone System

While head-up displays let you keep your eyes on the road, Bluetooth lets you keep your hands on the wheel when using a mobile phone. The technology establishes a wireless connection with a compatible phone so that calls can be made and received using buttons on the steering wheel and voice commands.

Voice Activation

Using voice activation, you can change a radio station or adjust the volume on the audio system, raise and lower the temperature of the climate control, even enter destinations into a nav system—all without lifting a hand off of the wheel.

Navigation Systems

GPS navigation systems take the guesswork out of getting where you're going—and are much safer than reading a map behind the wheel. They issue turn-by-turn guidance and will reroute you if you miss a turn.

Adaptive Cruise Control

Adaptive Cruise Control automatically keeps a safe distance between you and the car ahead so that the driver doesn't constantly have to adjust the speed. A radar sensor monitors the distance and speed of vehicles in front of you, and most systems allow selecting a gap with which you're most comfortable.

Rearview Camera

Rear-vision cameras first appeared on super-sized SUVs to help drivers see behind the vehicles. But they are now available on luxury and sports cars as well as minivans and crossovers. Some also include visual aids that allow aligning a vehicle with an intended parking spot.

Obstacle Sensors

As with rear-vision cameras, obstacle sensors can help make you aware of objects you wouldn't normally see. The systems detect objects in close proximity to the vehicle and issue audible and/or visual warnings.

Emergency Response

OnStar and similar telematics services are known for "concierge" features such as unlocking doors and providing directions. But in the case of an accident they can pinpoint your location and detect if an airbag has deployed so that emergency personnel can respond accordingly.

Heartbeat Monitor

The key fob remote for the 2007 Volvo S80 will not only tell you if someone has broken into the vehicle while you were away, but a heartbeat sensor will alert you if someone is hiding inside.

While safety technology can save lives, features such as electronic stability control can also give drivers a false sense of security. "People may not understand that if you don't maintain your brakes, for example, the stability control won't work properly," maintains Lauren Fit, a.k.a., The Car Coach. And while safety technology compensates for human error, it can't make up for lack of common sense. "Nothing takes the place of putting down the phone and paying attention to what you're doing," remarks J.D. Power's Charlie Vogelheim.

Doug Newcomb has been writing about car electronics since 1988, as editor of Car Audio and Electronics, Car Stereo Review, Mobile Entertainment, Road & Track Road Gear and as a freelance writer. He lives in Hood River, Oregon.

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