One of the latest things to come out of German lighting and electronics supplier Hella KGaA Hueck & Co. (Lippstadt, Germany; www.hella.com) was actually the result of collaborative research performed with the nearby University of Paderborn. The privately held supplier created a partnership with the university in 2000, the L-LAB, where automotive lighting research is performed. There are 17 researchers and 20 students in the lab, some of whom are in what is called the “Human-Machine Interaction Group.” It was there that researchers studied design parameters for, and user acceptance of, an adaptive light distribution system designed to increase visibility through greater high beam usage.
According to Dr. Christian Amsel, director of Hella’s Research and Development, Light-Based Driver Assistance systems, the number of motorists seriously injured or killed at night ranges from 30% to 40%, and high beam use—though increasing—sits at approximately 25%. “Increased use of high beams could significantly reduce the number of injuries and fatalities,” claims Amsel. He states that, even with current lighting technology, low beams are ineffective at highlighting objects at speeds as low as 40 mph. Yet, using the high beams in many situations—especially those with oncoming traffic or vehicles directly in front—brings a danger of its own. “The answer,” he states, “is an adaptive light distribution system that modifies the lights’ cutoff line to mirror the situation.”
As currently proposed, the system would require a camera, control unit and electronics, and dynamic module in addition to the standard headlamp. The “VarioX” adaptive module envisioned by Hella uses a single light source, a drum that acts as a shutter, and has the ability to swivel and rise to put the light where it is needed. The proof-of-concept unit involved a simple two-position shutter to provide both low and high beams from a single light source. It advanced to the addition of a five-position drum to create five distinct light patterns—city, country, adverse weather, highway, high beam—and an active unit with a continuously moving drum is under development.
Taking cues from the forward-facing camera mounted above the vehicle’s inside rearview mirror, the drum rotates in concert with the light source’s ability to rotate about its axes to create the appropriate light cutoff. “This optimizes the use of the high beam,” says Amsel, “as well as road space illumination, and takes care of any switching necessary from low to high beam. And while complicated compared to standard lighting units, testing by the Human-Machine Interaction Group showed the system added about 30 meters to driver recognition of objects both moving away or toward the vehicle. “There is a significant reduction in response time when objects are directly marked and beyond the range of the low beam,” says Amsel. Of the total 1.26-second reduction observed in testing, nearly one second was attributable to faster perception and realization.
Hella plans to have its five-position adaptive front lighting system ready for production by 2009, with the continuously adaptive system in place by 2012. In addition, it is developing an LED Matrix Beam in which every single-chip LED illuminates a defined area of the road. “This will mean bend, motorway, and cornering lighting can be produced in a single headlamp unit without the need for mechanically driven parts,” says Amsel.