Safety potential of advanced headlighting systems

Michael J.Flannagan

The University of Michigan, Ann Arbor,Michigan USA

Abstract—There are well-established safety needs in the areaof vehicle headlighting. Models of the ability of drivers to stop indicate thatmost low-beam headlighting systems do not provide adequate preview distance forthe full range of typical nighttime speeds. There is also evidence that manyvehicles in use do not have proper adjustment of headlamp aim, therebyincreasing possible problems with seeing distance. New developments inheadlighting, including adaptive driving beams (ADB), offer possibleimprovements in this situation. Although it is difficult to fully quantify thelikely benefits of these developments, it is at least possible to quantify thesafety needs that they might address. We have developed estimates of suchsafety needs from crash data, using analyses that separate the effects of thedarkness of night (which in principle can be addressed by improvements in headlighting)from other causes of risk at night (such as alcohol and fatigue, which inprinciple are unlikely to be addressed by improved headlighting). We presentestimates for the resulting safety needs by factors such as vehicle speed androad geometry.

Keywords-headlighting, crash data, safety