Analysis of Human Intra- and Interpersonal Aiming Accuracy of Cutoff Lines Using Different Adjustment Methods 2021-01-0849

In this paper, the human intra- and interpersonal adjustment accuracy (or aiming) of headlamp cutoff lines with different methods are examined. Intrapersonal aiming accuracy is the repeatability of a single person, while interpersonal aiming accuracy describes the differences between different people. For this purpose, a study is developed, implemented and evaluated. In one experiment, the subjects set up three different headlamps using three different methods according to the ECE regulation. In addition, the three adjustment methods used are compared with each other and evaluated in terms of the variation resulting aim. The most common aiming method, the visual adjustment of the cutoff line, such as the 10-meter wall method or analog headlamp aiming devices shows the highest variations. It is shown that digital headlamp aiming devices generally also have a lower dispersion variance, while still being better than all other adjustment methods. The human adjustment accuracy for headlamp systems depends on the quality of the light distribution and especially on the cutoff line. Therefore, due to the significantly better repeatability, digital aiming systems are preferable to human evaluation. Additionally, it can be stated that headlamp aiming is subject to a tolerance which must be taken into account when designing the product. Particularly in a fair comparison between different headlamps. There is no technical product and no scientific examination without tolerances, this also applies to lighting technology.