EHRA LESSIEN, Germany –AG will pursue a number of advanced technologies focused on improving vehicle safety and efficiency, including a brake-assist system to soften crash impacts and a far-reaching concept to automate portions of the driving cycle.
Some of the technologies under scrutiny already appear in various form invehicles, while others may never find their way into production. But each builds on existing technology, such as the video cameras, laser sensors and radars used for lane assist and adaptive cruise-control systems already available on European-market versions of the Passat CC, which recently went on sale in the region.
Jürgen Leohold, executive director-Group Research, calls the safety technologies “an angel to protect the driver” through information, warnings and assistance, including automatic crash avoidance.
Adds Leohold: “Our vision is not fully automatic driving, but assistance in annoying situations,” such as long-distance trips or stop-and-go traffic, and under defined conditions, specific situations and selected roadway locations.
Before getting the green light for production, “the automated system must see like a real driver and react like a real driver,” he says during a recent demonstration of Volkswagen technologies at the auto maker’s sprawling proving grounds near here.
VW’s “iCar,” or Intelligent Car project, draws on learning from Stanley, one of the company’s DARPA Challenge concept cars, and the Golf 53 research vehicle.
DARPA, or the Defense Research Projects Agency, is a U.S.-based competition challenging engineering teams to build a prototype vehicle capable of fully automated driving. In 2005, the Toureg-based Stanley won the DARPA Desert Challenge.
Golf 53 originally was developed to help with vehicle testing, but two years ago it autonomously sped around German racetracks at 150 mph (241 km/h).
The Passat makes an ideal platform for automated driving technologies, VW says, because it already includes core company competencies such as electro-mechanical power steering, an electronic throttle and an electrically actuated parking brake that can be controlled by a computer. The Passat’s available, quick-shifting dual-clutch transmission also contributes to iCar’s effectiveness, VW says.
The iCar prototype under demonstration here leverages those same technologies. But unlike the DARPA vehicle, all of the computer hardware is tucked neatly into the Passat-based iCar’s rear cargo area and its 360-degree cameras, radars and sensors are integrated out of sight. A single actuator electronically controls throttle, brake and steering.
Another key difference exists between the competition prototypes and iCar, says Arne Bartels, who heads the iCar program.
“We’re looking at customers; they were looking for knowledge,” he says.
Not quite as capable as Stanley, iCar still manages to perform in impressive fashion the basic driving functions Volkswagen would like to automate.
For instance, during a test drive, the Volkswagen engineer in the driver’s seat takes his hands off the wheel and allows the Passat to automatically slow to a stop when traffic ahead does the same. The car is able to perform a passing maneuver, but as our pilot says, “It’s a German car, so never on the right.”
Perhaps more impressive, as iCar approaches a curve in the road at 81 mph (130 km/h), four computers rapidly crunch data from lane-position cameras and a highly precise navigation system to automatically slow the vehicle to 53 mph (85 km/h). It then negotiates the long turn as smoothly as if Michael Schumacher were behind the wheel.
Volkswagen claims iCar will remain in the middle of its driving lane with “centimeter precision.”
Bartels says iCar addresses the topics of driving enjoyment, passenger comfort, and environmental protection. But most of all, it might make travel safer by automating monotonous, long-distance drives and stop-go-traffic.
Those are times, Bartels says citing a recent “100 Car” study from Virginia Technological University and the U.S. National Highway Traffic Safety Admin., when drivers are least attentive, often performing such secondary tasks as talking on cell phones or eating.
“So the question is, why not give drivers a tool so they can do the secondary tasks without risk?” Bartels asks.
If the system ever reaches production, it will emerge first as a tool to help with stop-and-go traffic, he says, adding, don’t expect a day soon when the driver might turn his attention away from steering altogether.
“The driver will always have some responsibility,” Bartels says, noting the hardware would need to shrink to the size of a car radio for the system to become feasible. “It will take some time.”
Pedestrians represent “a major problem,” Bartels admits. “Assisted driving, yes, but in the near future no automated driving in urban situations.”
Although Volkswagen completed work on the iCar project last month, development will continue through a European Union project called “Have It” (Highly Automated Vehicles for Intelligent Transportation).
Have It will promote the concept of “automatic driving” and operate out of the newly founded Research Center for Vehicle Technology of Lower Saxony initiative at the Technical University of Braunschweig near VW headquarters in Wolfsburg.
Volkswagen also demonstrates its PyroBrake system, a technology much closer to production that leans on the auto maker’s existing adaptive cruise control.
PyroBrake uses a stereo camera and radar sensors operating at 24 GHz and 77 GHz to detect an impending crash and initiate hard braking within 80 milliseconds. It works up to 300 milliseconds faster than current automatic emergency braking technology, which is about the time it takes for a pedestrian to take one step into traffic.
Martin Gonter, an engineer on the PyroBrake program, cites a study showing 48% of drivers fail to brake in a frontal collision. He says PyroBrake could be especially helpful at intersections, where pedestrians may appear suddenly in the vehicle’s path.
“The question now is how to detect an unavoidable collision without any false alarms,” Gonter says, declining to offer a production timetable.
But on the test track here, the system works without a hitch, applying 1,450 psi (100 bar) of extra pressure before a specially outfitted Passat strikes a yellow impact box about the size of three tires. It slows the car in an instant from 30 mph (48 km/h) to 26 mph (42 km/h).
As hardware, PyroBrake is a small, additional piston unit within the antilock brake system. Once the camera and radar sense an impending impact, the piston fires “pyrotechnically,” much the same way as a seatbelt pretensioner.
On average, PyroBrake reduces impact by about 3 mph (5 km/h). In terms of energy, slowing a vehicle from 31 mph (50 km/h) to 28 mph (45 km/h) is equal to a reduction from 12 mph (20 km/h) to zero, Volkswagen engineers say.
If the system were to ignite on a production vehicle, the owner would have to visit the dealer to have it reset.
“But if there is a collision, you would have to go to the dealer anyway,” Gonter adds. “The main thing is you’ll have less severe accidents.”
Volkswagen engineers say further integration of vehicle sensors, radars and cameras will play the biggest role in making systems such as automated driving and PyroBrake a reality. But they also think Volkswagen’s expertise in areas such as electromechanical steering has given them a head start.
“The steering system is a great advantage for us,” says Tobias Giebel, who helped develop a lateral-assistance technology to help drivers negotiate construction zones. It adds only one camera and several lines of software, but working with the car’s lane assist system automatically provides transverse and longitudinal guidance.
“Electro-mechanical steering is in every Passat we sell, every Jetta we sell and every Eos we sell,” he adds. And as a manufacturer of mostly economical cars, Giebel says technological advances won’t arrive unless they’re cost-effective.
“The Passat is our S-Class,” he says.