Barton Sease: Dynamic Stability Control. Its been said its nearly as important to driver safety as the seatbelt.
Bryant Pillitteri: "Active Cruise Control"
Alise Rutgers: Antilock brakes (ABS)Before antilock brakes came along, it was all too easy to lock up the wheels (stop them turning) during hard braking, particularly on slippery surfaces. When the wheels lock up, the vehicle tends to keep plowing ahead in whatever direction it was going. You can't steer, and locked wheels can cause a vehicle to slide sideways. ABS prevents this from happening. Antilock brakes use wheel-speed sensors at each wheel and a computer that coordinates the braking action, rapidly pulsing the brakes on and off when you hit the pedal hard. By preventing lock-up, ABS allows the driver to retain steering control while braking, so that the car can be maneuvered around an obstacle, if necessary.Brake assistMercedes-Benz pioneered this adjunct to ABS. By sensing the speed or force with w! hich the brake pedal is depressed, it determines if the driver wants to make an emergency stop. If so, it makes sure the ABS is activated and boosts brake pressure. Brake assist is available on some Audi, Lexus, Mercedes, Nissan, and Toyota vehicles, among others.Traction controlThis electronically controlled system limits wheel spin during acceleration so that the drive wheels have maximum traction. It's particularly useful when starting off in wet or icy conditions. Some traction-control systems operate only at low speeds, while others work at all speeds.Most low-speed traction-control systems use the car's antilock brake system. If the system detects wheelspin while accelerating on a slippery surface, it momentarily applies the brakes to the slipping wheel. This stops the slipping and automatically routes power to the opposite drive wheel. All-speed traction control uses a combination of ABS and powertrain control. In slick conditions and at higher speeds, a system of se! nsors and computers may upshift the transmission, throttle bac! k the engine, and apply the brakes--or a combination of these--to prevent wheelspin.Safety-belt featuresWhile the seatbelt is arguably the single most important piece of safety equipment, enhanced belt features are helping seatbelts do their job more effectively.Adjustable upper anchors for the shoulder belts can make a meaningful safety difference. Adjustable anchors help position the belt across the chest instead of the neck to prevent neck injuries. They also can help keep the belt from pulling down on a tall person's shoulder, making it more comfortable and encouraging its use.Seatbelt pretensioners instantly retract the belts to take up slack during a frontal impact. This also helps position occupants properly to take full advantage of a deploying airbag. Force limiters, a companion feature to pretensioners, manage the force that the shoulder belt builds up on the occupant's chest. After the pretensioners tighten it, force limiters let the belt pay back out a little.El! ectronic stability control (ESC)Electronic stability control takes electronic traction control a step further. This system helps keep the vehicle on its intended path during a turn, to avoid sliding or skidding. It uses a computer linked to a series of sensors--detecting wheel speed, steering angle, sideways motion and yaw (spin). If the car starts to drift, the stability-control system momentarily brakes one or more wheels and, depending on the system, reduces engine power to keep the car back on course.ESC is especially helpful in providing an extra measure of control in slippery conditions and accident-avoidance situations. With tall, top-heavy vehicles like sport-utilities and pickups, it can also help keep a vehicle from getting into a situation where it could roll over.Ford and Volvo have taken stability control a step further with Roll Stability Control (RSC). It uses gyroscopic sensors to determine roll angle and roll speed to determine if a rollover is imminent. If! so, it triggers the standard stability control system and instantly re! duces power and brakes the necessary wheels to bring the vehicle back under control. This system is found on the Volvo XC90, Ford Explorer, Expedition, and Lincoln Navigator SUVs among others.General Motors and Chrysler have introduced competing rollover-mitigation systems. GM's is called Proactive Roll Avoidance (PRA), and Chryslers is called Electronic Roll Mitigation (ERM). They are found on the 2007 and later Cadillac Escalade, Chevrolet Tahoe and Suburban, GMC Yukon, Jeep Compass and Wrangler, among other vehicles.Electronic stability control started on luxury cars and has been migrating to SUVs and many other vehicles. To confuse matters, automakers each tend to have a proprietary name for their stability control systems (see the accompanying table). To help consumers identify the system in a vehicle's features list, the Society of Automotive Engineers has asked that all manufacturers use electronic stability control or ESC, as common terminology when referring to the! ir stability-control systems. Consumer Reports supports this move because it will help consumers know what they are buying. If in doubt whether a car has it, find out before you buy.Tire-pressure monitorUnderinflated tires can hurt handling and fuel economy, as well as cause premature wear--or a possible blowout--of the tire. Yet a tire can lose air so slowly that many drivers don't realize it's happening. A government regulation requires all new vehicles made after October 31, 2006 to have a low-tire-pressure warning system. The type of tire-pressure monitor we favor measures tire pressure directly. A competing technology, and one the government has approved, gauges air loss indirectly by using sensors to count wheel revolutions. We don't think those systems are sensitive enough. In any case, we suggest regularly checking your tires with a conventional tire-pressure gauge.TelematicsCombining cellular telephone and Global Positioning Satellite (GPS) technology, several majo! r automakers are offering an automated service that provides a high lev! el of security and convenience. GM was the first with its OnStar service, followed later by Mercedes-Benz's TeleAid, BMW Assist, Volvo OnCall, and Lexus Link. All use the same technology and offer basically the same services. In operation, with the touch of a button the driver can communicate with a central dispatch center, where the location of the vehicle can be tracked on a computer monitor to provide route directions or emergency aid. If a vehicle's air bag is deployed in a collision, the system automatically notifies the dispatch center, locates the vehicle, and sends emergency aid if the driver does not respond to an inquiry. A phone call to the dispatch center can find a "lost" car in a parking lot by beeping the horn, or unlock the doors if the keys have been misplaced. OnStar is available on all GM cars and trucks, as well as on Saab, Acura, Audi, and other makes. TeleAid is offered only on Mercedes-Benz models. Additional systems include BMW's Assist and Volvo's O! ncall. The cost of the system is built into the price of most vehicles, but a monthly service fee is usually required....Show more
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