A Grid-based Surrogate Safety Measure for Traffic Safety Assessment

Assessing the traffic safety and an impact of Advanced Driver Assistance Systems (ADAS) on it based on collision data is a challenging task since the crashes are rare and usually there is a lack of high quality accident data. Still, in order to be able to evaluate the performance of ADAS, different Surrogate Safety Measures (SSMs) are continuously introduced in the literature. Unfortunately, single SSMs have in general a limited application scope, so that combining several SSMs seems a sensible option. However, combining them to produce a single value is difficult, as there is not a clear guideline about the different weights. Against this background, in this paper we propose a grid-based SSM characterizing the traffic safety by 6 categories ranging from conflict-free to safety critical. The advantages of the approach include the ability to perform a more comprehensive traffic safety analysis or an efficient comparison of different ADAS by their impact on safety. The latter one is illustrated by simulation-based comparison of three Adaptive Cruise Control (ACC) set-ups.