“Driver assistance” is a phrase that can send a shudder of concern through the administrative and financial hierarchy of the motor industry as technologists come up with yet another solution to a problem that may be difficult to discern. It can create added complexity and cost, and the end user can become thoroughly discombobulated by a multitude of system choices and functions that may effectively increase workload and require too much attention, thus defeating their raison d’être.
All this is very much on the minds of engineers and designers at Volkswagen’s Wolfsburg R&D center while considering the words of VW Group Chairman, Prof. Dr. Martin Winterkorn: “Volkswagen is the large-scale brand that stands for innovation and engineering prowess.”
Many new driver assistance technologies are primarily concerned with safety and ease of use, but they need to be carefully developed and applied to give easy to understand alerts and also to maximize use of existing components, sensor and system bundling, and efficient packaging. Relevant sensors and supporting systems for safety and driver support include ultrasonics, radar, cameras, and Wi-Fi, all under the umbrella heading of communications: car to car, transport infrastructure to car/driver, vehicle to driver.
Driver friendliness is a must, and AEI experienced several of VW’s development programs to inform, warn, and support drivers facing potential hazards.
VW is bundling emergency assist, advanced lane assist, and partial vehicle piloting systems to help control the outcome of a medical emergency or the effect of driver fatigue.
“It is about keeping the vehicle of an unconscious, sleepy, or inattentive driver in a lane and stopping the vehicle safely,” explained Development Engineer Bastian Schmidt. “It involves a warning to the driver, slowing the vehicle to a stop if necessary, and operating the hazard warning flashers, the whole process—depending on speed—taking about 10 to 20 seconds.”
The process is initiated by a total lack of steering inputs over a specified period or if the driver’s hands are not on the steering wheel. Lane assist keeps the car within the bounds of the lane in which it has been traveling provided there are lane markings. The hazard lights are initiated and radar-based adaptive cruise control is engaged to prevent a collision with any vehicle/object ahead.
An initial quiet acoustic warning is given (the theory is not to startle the driver), followed by a louder sound if necessary (this AEI editor felt the louder sound should be applied at the start of the perceived emergency), and the brakes are applied briefly but sufficiently hard to awaken a sleepy/sleeping driver. If there is still no driver input with hands on the steering wheel, the vehicle is brought to a standstill.
VW believes it will be first to market such a system.
Car2X communication is a particular area within which applications are set to burgeon. One concerns road works (construction).
Volkswagen’s Car2X Safety involves the exchange of information between vehicles and transportation infrastructure with an automotive WLAN (wireless local area network) standard forming the foundation of the communication. In effect, said VW’s C2X Development Engineer Florian Weinert, it is a system that can allow the driver to “see” round corners: “For example, if there is a construction site on the road ahead, but out of an approaching driver’s vision, his or her car can receive a warning message.”
This is transmitted by a car ahead or via a portable piece of site infrastructure. It first involves an alerting caption in the driver’s information display, followed by an audible warning and a countdown to the hazard in meters.
Consideration is being given to linking the system to a head-up display as an attention getter, possibly using an exclamation mark to take the driver’s eyes to the instrument display, or to give a distance-to-hazard message.
The Car2X communication is regulated by the ITS G5 standard of the ETSI (European Telecommunications Standards Institute) and actions of the European Car 2 Car Communication Consortium (C2C-CC)—a non-profit, industry driven organization initiated by European vehicle manufacturers and supported by equipment suppliers, research organizations, and other partners. The C2C-CC is dedicated to further increasing road traffic safety and efficiency by means of cooperative Intelligent Transport Systems (C-ITS) with vehicle-to-vehicle (V2V) communication supported by vehicle-to-infrastructure (V2I) communication.
Car2X Safety enables networked mobility over a distance of several hundred meters, with multiple exchanges of information occurring by the second, explained Weinert.
And when a car arrives safely at the roadworks site, VW has further safety aids for the driver, using developments of established lane assist technology to incorporate the Roadworks Assist function to help guide the driver along narrow lanes marked by cones or temporary guard rails, particularly at night or in low visibility conditions.
VW states that safety studies have shown that the greatest accident risk occurs when crossing the center line with a driving lane banking angle of 10%, lane width of 2.5 m, and maximum legal speed of 80 km/h over a bend radius covering 300 m.
To improve safety, the Construction Zone Assistant incorporates a stereo camera with stereo image processing plus a mono camera to detect lane markings, supported by four ultrasonic sensors to measure distances to other vehicles (especially trucks and buses) in any adjacent lane or lanes.
The fusion of camera data and ultrasonic sensor data produces a modular surroundings model, allowing a computer to achieve a driving corridor analysis that predicts the car’s direction, checks for possible collisions, and determines the desired direction of the driver’s vehicle.
Adaptive cruise control and brake assistant also play roles for steering correction and automatic braking as deemed necessary.
At night, Visual Driver Aid in roadworks is also being developed. Using LEDs, it “paints” two light stripes onto the lane ahead of a car to aid driver assessment of lane width. A further development of this could project variable lines in front of the vehicle that would represent the desired driving lane and also show potential interventions by the Construction Zone Assistant.
Development challenges at present include overcoming the risk of dazzle caused by the LED patterns being projected on to a wet surface.
Other systems being developed at Wolfsburg include a camera-based high-definition 3D bird’s-eye view of the vehicle and its surrounding area, including cross-traffic, blind spot monitor and rear traffic alert for reversing out of a parking slot with view shielded by other vehicles, and park assist for frontal approach to perpendicular parking spaces. Remote controlled driver out-of-vehicle technology continues to be developed as does a trailer hands-off-the-steering-wheel reversing system using cameras but requiring the driver to preselect the trailer angle.
An electromechanical brake booster (eBKV) to improve established automatic braking systems is also being developed by VW. Designated Fast Brake and incorporating current production components to save manufacturing costs, it can cut braking distance from 30 km/h by 1.3 m. The system could help meet scheduled 2015 EuroNCAP and will be available in VW’s pure-electric vehicles. It would also be suitable for hybrids, with further applications likely.