Analysis of Detection Distances and Road Safety of Modern Headlamps Under Variation of Aim and Performance

In addition to the low and high beam functions, some modern headlamps also have the option of switching on only section of the high beam. The so-called adaptive high beam is intended to increase the detection distance of objects and through that drastically improve the road safety. At the same time, this function does not increase the glare for oncoming or preceding traffic. This is enabled through switching the different segments of the high beam on or off, depending on which and where other road users are recognized by the front camera. This massively increases the use of the high beam, thus increasing road safety. In this study, the increase in the detection distance of objects on a straight line is statically investigated with a test person study. Furthermore, the glare of each of these three light functions is observed. A vehicle with adaptive high beam and an oncoming vehicle are statically positioned on the test track and the detection distances and glare sensitivity are determined subjectively and metrologically by test persons. Already published studies have also shown that the headlamp aiming is subject to the natural tolerances of the vehicle and the environment. Therefore, the influence of the headlamp aiming on glare and detection distances is also investigated for all three light functions to draw conclusions about headlamp evaluation methods. The investigation shows a minimum increase of the detection distance of over 44% when an adaptive high beam system with 24 segments is used. A greater detection distance of 28m brings a safety gain of over 1.27s on a country road drive at 80 km/h. An increase in the glare of oncoming traffic could not be detected. Moreover, it could be shown that a change in the headlamp aiming mainly has an influence on the detection distance of the low beam and not on high or adaptive driving beam.