Vehicle–Bicyclist Dynamic Position Extracted From Naturalistic Driving Videos

Pre-collision systems (PCS) are designed to warn a driver or brake automatically to help avoid or mitigate accidents, protecting vulnerable road users such as pedestrians and bicyclists. A PCS system needs to understand both normal and abnormal behavior of the vulnerable users in order to have high true-positive and low false-positive detection of PCS events. In this paper, the normal bicyclist behavior is analyzed based on naturalistic driving data. These data can inform the PCS design and lead to proper testing and evaluation of PCS systems. This paper focuses on the following attributes of normal bicyclist behavior: time to collision, lateral position, and bicycle speed. The behavior was analyzed using the Transportation Active Safety Institute naturalistic driving data from 110 cars. This paper presents new analysis gleaned from these data, plotted in 2-D graphical form, showing heat maps of common bicycle positions and trajectories of the dynamic vehicle–bicycle interactions.