Field investigation of vehicle acceleration at the stop line with a dynamic vision sensor

This article presents a study of vehicle acceleration measurements at the stop line of a traffic light in an urban environment. Accurate representation of vehicle acceleration behavior is an important parameter to traffic simulation tools especially when the emissions related to the simulated traffic need to be calculated. A smart eye traffic data sensor (TDS) system was used to record the vehicle trajectories. This device is based on dynamic vision sensor technology that features 1 millisecond temporal resolution, wide dynamic range of 120 dB of illumination, zero-redundancy and asynchronous data output. The trajectories of the detected vehicles from the vision sensor temporal contrast event data have been manually annotated in a space-time representation using a graphical tool. From these extracted trajectories the acceleration of the vehicles has been calculated. We present results of acceleration distributions obtained from over 300 passenger-car acceleration cycles observed in the field. The measurements focus on the first phase of acceleration from the stop line up to a maximum speed of 40 km/h. The results are compared to the results from a traffic micro simulation tool obtained for a similar stop line scenario. The results will be used in the traffic micro-simulation that serves as a basis for a decision support tool for adaptive traffic management developed in the CARBOTRAF FP7 EU project.