by Joseph D. Younger

With new advances in crash avoidance technology, will your next car say, “Leave the driving to me?”

For decades, carmakers and government regulators built safety systems upon one bedrock assumption: someday, somewhere, your car might crash. They gave us safety belts, airbags, crumple zones, side-impact reinforcement, laminated windshields, collapsible steering columns, and other clever devices, all designed to prevent deaths and injuries when your vehicle slams into something or something slams into you.
They call these characteristics “crashworthiness.”

In recent years, however, the National Highway Traffic Safety Administration (NHTSA) began thinking about safety in a whole new way, focusing its research and regulatory attention to preventing crashes from occurring in the first place—what experts call “crash avoidance.”

“We are reaching the point of diminishing returns by focusing only on crashworthiness,” then-Administrator Jeffrey Runge told a group of journalists at the Detroit Auto Show last year. “The biggest return on investment in terms of lives saved and injuries prevented in the future will come from accelerated development and deployment of crash avoidance technologies.”

Runge’s announcement marked a turning point: NHTSA would devote more energy to analyzing the effectiveness of such high-tech systems and setting performance standards for them.

Runge acknowledged his agency was coming to the party a little late.  Lots of cars now have systems to help avoid crashes, such as anti-lock brakes, which allow you to steer around obstacles in an emergency stop. Some have electronic stability control, which helps you recover from a front- or rear-wheel skid if you take a curve too fast. Back-up warnings, which use lights or sounds to warn that you’re about to hit something while going in reverse, are gaining in popularity.

These systems come with several nagging questions. Will crash avoidance technology prevent real-world collisions? Will drivers accept it? How much control should be ceded to computers? And, ultimately, how do you feel about a car that may be smarter than you are?

“Vaccinating” Against Crashes
One reason engineers and regulators are concentrating more on crash avoidance is the belief they’ve gone about as far as they can go with crash protection.

Traffic fatalities in the U.S. have hovered at about 42,000 annually in recent years without much improvement.

“We’re not making the gains that we used to,” notes Dr. Joseph Kanianthra, NHTSA’s associate administrator for vehicle technology.
To some traffic safety experts, crash prevention is to traffic injuries and fatalities what vaccinations are to measles, mumps, and other diseases. Preventing illness in the first place becomes far more cost-effective (in both human and economic terms) than treating patients once they’re sick.

“Computers, sensors, and other technologies have advanced considerably in the last decade or so,” says Jim Grey, president of AAA’s AutoMark repair facilities and an automotive engineer, “and they present more opportunities.”

More sophisticated technology offers the chance to warn drivers of imminent crashes—or trigger the vehicle itself to take action. 

Coming Soon to a Car Near You
But traffic safety experts admit some technologies also hold the potential for increased distractions and other unintended behind-the-wheel consequences.

If you can’t wait to try out advanced crash avoidance technology for yourself, look for the following options.

Lane Departure Warning
What It Does: A buzzer sounds and a warning light comes on when you drift inadvertently left or right, either out of your lane or off the road, without using your turn signal.

How It Works: A tiny camera mounted on the rearview mirror “reads” lane markings, roadway edge lines, and bot dots (raised reflectors between lanes), sending signals to a computer. The computer calculates the vehicle’s forward speed, lateral movement, and distance from the lane markings and “decides” whether you’re drifting.  Signaling your intention by flipping on your blinkers precludes a warning.

Advanced Cruise Control
What It Does: Introduced several years ago and now available on several makes, adaptive cruise control automatically maintains a safe cushion of space between your car and the one in front of you, regardless of changes in prevailing traffic speed.

How It Works: Using either radar or a laser beam that projects from an opening in the grille, a computer measures the distance to the car ahead and adjusts speed accordingly. Most systems automatically calculate a three-second following distance (about 250 feet on the highway), but allow the driver to adjust it using a dial on the steering wheel—within limits, of course.  It won’t let you get close enough to “automatically” tailgate. And it works only at highway speeds.

Drowsy-Driving Monitors
What It Does: Detects sleepiness in drivers.
How It Works: “We’ve found that a percent of eyelid closure over time is a good metric to determine how drowsy a driver has become,” explains NHTSA’s Kanianthra. “We’ve looked at infrared and laser beams as a way to monitor eyelid closure, but cameras may prove to be the most reliable option.” NHTSA is now field-testing such a system on a fleet of 40-odd big, long-haul trucks.

How It Works: Current systems use pedal sensors to detect rapid movement of the driver’s foot from the accelerator to the brake pedal. The sensors send signals to a computer, which in turn pre-pressurizes the hydraulic system and squeezes the brake pads a bit closer to the discs, increasing response time and decreasing stopping distance. Some systems use a laser beam to judge the distance to objects ahead, a computer calculates your car’s speed and the system knows it needs to brake before you even take your foot off the accelerator.

The list doesn’t include so-called “vision enhancements” now available or on the way, which also fall under the broad rubric of crash avoidance technology. They include adaptive headlights (which adjust their angle along with the steering system to shine around curves and corners), rear-vision and blind-spot cameras (which improve visibility as their names imply and sometimes sound warnings as well), and night-vision head-up displays (which use infrared cameras to project images of people or objects beyond the reach of your headlights).

Although fine in theory, no one yet has much empirical evidence about whether these technologies actually prevent crashes. Proponents rely on common sense and statistics to make their case.  For example, Kanianthra points out three types of collisions—rear-enders, run-off-the-road crashes, and improper lane changes or merges—together account for nearly 70 percent of all vehicle mishaps on American roads. Technologies that would help drivers avoid these errors would provide big payoffs in lives saved, injuries mitigated, and property left undamaged.

To date, NHTSA has analyzed real-world data on only one widely used crash avoidance technology—electronic stability control. The study demonstrated a clear, unquestionable benefit. Over the past six years, the high-tech system has reduced single-vehicle crashes by 67 percent in sport-utility vehicles and 35 percent in passenger cars.

However, the government will need more data from real-world crashes and field tests before it can come to similar conclusions about other systems.

Who’s Driving, Anyway?
Then there’s the question of whether drivers will accept—much less pay for—technology that tells them how to drive. The market looks promising. According to Tier One, an automotive electronic market research firm, sales of such systems are expected to increase nearly 20-fold by year 2010.

NHTSA’s Kanianthra echoes the sentiments of many crash avoidance experts when he says, “I’m not an advocate of automated driving. We want the driver to remain in control of the vehicle. Most crash prevention technology is based on warnings. It has to be seamless and unobtrusive. In order to be accepted, it can’t cause an annoyance to the driver or overload him [with too much information].”

To skeptics, however, such statements may ring hollow—particularly when you consider technologies obviously intended to wrest vehicle control away from the driver, if only for a moment or so, such as the lane departure warning.

AAA’s Grey foresees crash avoidance technology evolving with real world experience, like airbags and computerized engines. Soon after airbags became standard equipment safety problems arose for small adults and children. On-off switches were added, and deployment power was reduced or staged depending on occupant size and crash severity, and drivers learned to sit 10 inches away from the steering wheel and seat children in the back.

“There’s a delicate balance between giving up some degree of control for safety’s sake and maintaining the decision making freedom behind the wheel,” said Grey.

Whether crash avoidance designers have struck the right balance will become clear only after more experience with real drivers in real-world traffic situations.