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Smart Cars PUBLIC ACCESS

Knowledge is Power ... and Safety.

[+] Author Notes

Associate Editor.

Mechanical Engineering 125(03), 50-52 (Mar 01, 2003) (3 pages) doi:10.1115/1.2003-MAR-2

This article focuses on features and benefits of intelligent driver assistance systems. A combination of radar and vision systems helps a driver to better sense his/her crash envelope. Using a highway simulation model, research teams have found motorists tending to overcompensate for slowing traffic ahead. The model indicated that 10 percent of the cars fitted with driver assistance would reduce the problem by eliminating excessive braking. Twenty percent of vehicles using such systems would eliminate traffic jams altogether. Delphi aims its roll control system specifically at topple-prone SUVs. Active controls eliminate body roll in corners and during evasive maneuvers. A semi-active version removes the performance compromises that afflict dual-purpose, on-/off-road vehicles. Assist Ware Technology Inc., Wexford, PA, builds an alertness aid that combines lane position monitoring with a road-departure warning. A small video camera watches the road ahead from the dashboard. Any weaving or drifting off track triggers the alarm.

Although they’ve been Demonstrated, Self-driving, autonomous cars aren’t quite ready for prime time, Bernard Robertson told reporters attending DaimlerChrysler’s North America Innovation Symposium in New York last fall. Robertson, the senior vice president for engineering technologies and regulatory affairs, emceed the event.

But while we’re waiting for smarter highways, the technology necessary for making driving accident-free— or for substantially reducing the incidence of accidents— is nearly here.

A DaimlerChrysler management board member, Klaus-Dieter Vöhringer, said that the U.S.’s year-2000 count for deaths by auto totaled 42,000 and the tally for car-crash injuries that year reached 3 million. Nine out of ten of those crashes were caused through human error, Vöhringer said. In more than 20 percent of those cases, sleep was the culprit.

Think, for a moment, how many people you’ve known who have died in automobile accidents.

“In the future, at least every second road traffic accident could be prevented if vehicles are equipped with suitable assistance systems,” Vöhringer predicted.

A worthy goal, if ever there was one.

It would seem that many collisions might be preventable if drivers would pay better attention. But with all the distractions these days—cell phones to answer, makeup to apply, radio stations and CDs to change, sales reports to file—the average driver may need help in determining the best time to watch the road. The only answer—always—seems to get preached more than it gets practiced.

Yet poor visibility, unexpected objects in the road, even blowouts, can hamper the most attentive of drivers. In a flash, they wind up off piste, or worse.

The U.S. Department of Transportation, through the 1998 Intelligent Vehicle Initiative, identified eight areas where intelligent systems could “improve” or “impact” safety. The list includes four kinds of collision avoidances: rear end, lane change and merge, road departure, and intersection; two kinds of enhancements: vision and vehicle stability; and two kinds of monitoring: driver condition and driver distraction.

Besides reducing collisions, driver assistance systems may unblock clogged highways one day, according to Martin Treiber and Dirk Helbing of the Technical University of Dresden in Germany. Using a highway simulation model, they found motorists tending to overcompensate for slowing traffic ahead. The model indicated that 10 percent of the cars fitted with driver assistance would reduce the problem by eliminating excessive braking. Twenty percent of vehicles using such systems would eliminate traffic jams altogether, they found.

A combination of radar and vision systems helps a driver to better sense his crash envelope.

Grahic Jump LocationA combination of radar and vision systems helps a driver to better sense his crash envelope.

The first inklings of intelligent systems to emerge commercially were in high-end cars. Mercedes-Benz, BMW, and Jaguar introduced active cruise control in the United States early in the ’00s and in Europe a year or so earlier.

Similarly, adjuncts to anti-lock braking systems, such as brake assist and traction control, debuted in expensive cars, but are now finding their way onto cheaper vehicles, minivans, and sport utility vehicles. Continental Teves AG of Frankfurt am Main, Germany, builds an electronic stability system that combines anti-lock brakes with electronic brake force distribution, traction control, and active yaw control. By polling steering wheel, lateral acceleration, yaw rate, and wheel speed sensors, the system can detect deviation in a vehicle’s intended course. Automatically throttling the engine and applying the brakes differentially corrects understeer or oversteer to bring the vehicle back on track.

Delphi aims its roll control system specifically at topple-prone SUVs.

Active controls completely eliminate body roll in corners and during evasive maneuvers. A semi-active version removes the performance compromises that afflict dual-purpose, on/ off-road vehicles.

Delphi builds its collision warning system around several radar-based technologies. Its adaptive cruise control looks 150 meters ahead of the vehicle and maintains the driver’s desired speed as long as the path remains clear. The system will slow or accelerate according to a time gap set by the driver.

According to Milton Beach, a spokesman for Delphi Delco Electronics Systems in Kokomo, Ind., Jaguar introduced the second generation of Delphi adaptive cruise controls to North America with its 2003 models. The system includes a forward alert system that can advise a driver to brake in the presence of slowing traffic ahead. The system can alert the driver whether the cruise control is on or not.

Delphi packages its adaptive cruise control and a backup assistant in what it calls an Integrated Safety System. The backup aid has made its debut on several recent Ford and Lincoln SUVs.

Ready to go, but not yet slated for any particular model year, Delphi’s blind spot, lane change, and roadway departure warning systems may be the next step in the evolution of the smart car.

“We look at safety as a total system,” Beach said. That means the company applies safety systems to five stages of driving, he explained: normal, warning, collision avoiding, collision imminent, and collision past.

General Motors, through its partnership with Delphi Automotive Systems and the U.S. Department of Transportation, combines radar, vision, sensors, and GPS in its Automotive Collision Avoidance System. Radar looks ahead for vehicles and other obstacles. Video cameras watch lane position. Sensors monitor direction, latitudinal and longitudinal acceleration, yaw rate, steering angle, and wheel speeds. The global positioning system compares the car’s location to map coordinates that tell it what lies ahead. Monitors watching a driver’s distraction level complete the system.

Through algorithms, the system weights heavily what the preceding vehicle does and follows that. If the leading vehicle turns off, the system keys back to GPS data.

GM plans a field test of the experimental system in which 80 drivers will rotate through 10 cars so equipped. According to GM spokesman Jim Schell, a key reason for the test is to gauge customers’ acceptance of these new technologies.

Lane departure warnings mimic the sound of rumble strips. The sound comes from the side toward which the car veers. A waking driver can apply correction in the right direction instantly.

Grahic Jump LocationLane departure warnings mimic the sound of rumble strips. The sound comes from the side toward which the car veers. A waking driver can apply correction in the right direction instantly.

Market research says people want to maintain control of their cars, according to Robin Pannecouk, a spokeswoman for Visteon Corp. of Dearborn, Mich. Visteon’s system aims to increase a driver’s awareness and warn him when it lapses, rather than wrest control of the vehicle from him.

Tim Tiernan, senior manager of driver awareness systems at Visteon, said that the company is quoting lane-departure warning and side-object detection systems to OEMs for possible incorporation into vehicles selling 24 to 36 months hence. The vision-based lane-departure systems are benefiting from advances in semiconductors, he said.

During his presentation, DaimlerChrysler's Vöhringer described research under way that could one day protect pedestrians from automobiles. Such an “urban assistant system” could identify children running out into the street and halt or slow the car in time to prevent a collision. Or, if time was insufficient to prevent colliding, the system could change the shape of the normally aerodynamic car front to at least blunt the blow from an inevitable impact.

Akhtar Jameel, president and CEO of DaimlerChrysler Research & Technology North America, called intersections the “hot spots of road safety.” The urban setting overflows with visual information.

Recognizing in a cluttered visual field a child running out from between parked cars is difficult for purely optical systems, Jameel said. Researchers thus look to enhance visual systems by adding to them the capacity to recognize surface texture, silhouette, or gait patterns.

A Mercedes-Benz trial vehicle equipped with image processing electronics and stereo video and color cameras can detect pedestrians as well as traffic signs and signals, curbs, directional arrows, and crossings.

Ford Motor Co. is looking at pedestrian safety, too, not only from the perspective of sensing and warning pedestrians, but through active softening of the collisions with them. The company has developed a pedestrian-safety car that can deploy external airbags during a collision.

A Taurus concept car lights a red beam in the A-pillar to warn of imminent danger. Green means that all's clear.

Grahic Jump LocationA Taurus concept car lights a red beam in the A-pillar to warn of imminent danger. Green means that all's clear.

Going to work moments before impact, a pre-crash sensor in the safety car senses a pedestrian collision and inflates an over-the-hood bag just above the bumper. The bag remains inflated for several seconds. Two secondary airbags, triggered by a sensor detecting the initial impact, inflate in front of the windshield as the pedestrian is thrown toward it.

Originally designed for those denizens of late night, the long-haul truckers, lane-departure systems have been adapted lately to cars. AssistWare Technology Inc. of Wexford, Pa., builds an alertness aid that combines lane position monitoring with a road-departure warning. A small video camera watches the road ahead from the dashboard. Any weaving or drifting off track triggers the alarm.

Iteris Inc. of Anaheim, Calif., recently began selling a lane-departure warning system to OEMs in Europe and North America. The unit tracks visible lane markings with a dashboard camera and produces the sound of rumble strips as a car drifts out of its lane. A turn signal alerts the system to an expected lane change and mutes the warning.

In its Safety Concept Car, Volvo recently deployed the system together with other features, such as a mechanism that moves the seat, steering wheel, and pedals to place a driver in the best position for seeing.

Aside from provoking a wakeup call, a lane-departure warning could snap a driver’s attention back to the highway stripes and away from the many distractions that ricochet about the cabin of a modern car.

Just what those distractions are and how they influence driver safety are the kinds of questions researchers ask at Motorola’s laboratory in Tempe, Ariz. There, a class-2 driving simulator projects a virtual road scene on three screens out front and one screen in back. Electronic devices inside the car keep the driver distracted as researchers look on.

GM announced last April a three-year, $1.6 million study with the University of Illinois at Urbana-Cham-paign that will investigate driver distraction and how drivers interact with technologies inside the vehicle.

DaimlerChrysler engineers, along with researchers at MIT’s Media Lab, have been asking similar questions and seeking answers under actual operating conditions, Gerald Cilibraise, an engineering director, told the company’s technology symposium held last June near Stuttgart. The idea is to filter and reduce the amount of information bombarding a driver at any moment. By monitoring hand and foot positions, body posture—even eye movement— the system can determine a driver’s receptivity level. At the same time, the system watches the car to know its state, whether it’s negotiating a winding canyon road, stopping and going in dense traffic, or skipping along a highway.

According to Cilibraise, the system can suppress distracting information that’s trying to break into a driver’s thoughts while he’s concentrating on keeping his car on the road. As Cilibraise said, no one needs to be told the windshield washer reservoir needs filling just before making a left across a busy intersection.

As much as they might distract drivers, cell phones stand a pretty good chance of becoming the link to telematics, communications that keep the vehicle in touch with distant information and services.

“Who’s going to own the link?” remains the big question, according to Mark Fitzgerald, a telematics industry analyst with Strategy Analytics Inc. of Newton Centre, Mass. Motorists might balk about paying yet another monthly fee on top of the cell phone, cable, or home phone bills they’re already covering, he said.

GM’s OnStar system, for example, charges $16.95 monthly for its basic “Safe and Sound” service, which alerts an advisor automatically when an airbag deploys. Prices rise to $69.95 for the “Luxury and Leisure” package, which lets you call ahead to the restaurant to have a table ready.

Bringing telematics into the active crash avoidance system may be a ways off, Fitzgerald said. “Road scenario prediction” is the term industry applies to such systems that might advise a driver if his speed is too fast to safely negotiate an upcoming curve, for instance. For now, though, concentration is mainly on active traffic reports that warn of trouble ahead while drivers still have the time to seek alternate routes.

A 2003 concept Ford Taurus blends forward collision radar, low light cameras, blind spot monitoring, lane-departure, and rear-collision warnings with telematics. A phone can block incoming calls if pre-crash sensing and navigational data tells the system the driver is too busy to answer.

During the DaimlerChrysler symposium in New York, Robertson said that the level of intelligence the driving public will demand in its cars will ultimately spell out how much of this technology makes it to market. Tastes vary by region, he said. In Japan, for example, onboard navigation systems proved quite popular; in the United States, however, they didn’t.

Like many things, drivers conscientious enough to care about buying intelligent safety systems are probably operating their vehicles by the book already: checking blind spots by glancing over their shoulders, maintaining safe following distances, pulling over for naps when they’re sleepy.

For the most part, intelligent systems in our cars seem better suited to protecting other drivers from our own carelessness, rather than the other way around. Unless the woman driving and applying her makeup in the car behind you has collision avoidance, you’d better brace yourself if you have to stop short. No amount of rear-collision detection is going to change that.

Copyright © 2003 by ASME
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