Identifying Lane-Change Maneuvers with Probe Vehicle Data and an Observed Asymmetry in Driver Accommodation

Abstract

This paper uses an instrumented probe vehicle to monitor ambient traffic and overcome many challenges of observing traffic flow phenomena that occur over extended distances. One contribution of this paper is a general methodology to identify the probe vehicle’s lane of travel without a priori knowledge of where the lanes are. This knowledge is used to find the probe’s lane-change maneuvers (LCMs), to differentiate these LCMs from GPS errors, and, in conjunction with a ranging sensor, to identify which lanes the ambient vehicles are in to find their LCMs. The second contribution of this paper comes from the identified LCMS. The data are used to provide an independent validation of earlier studies, and thus yield further evidence of how LCMs contribute to the formation of disturbances within freeway queues. In particular, it is found that vehicles following an entering vehicle generally complete their response and return to steady state quicker than those following an exiting vehicle. As discussed herein, this asymmetry in the lane-change maneuver accommodation time effectively induces a ripple in the traffic state that propagates upstream. The resulting disturbances provide a possible mechanism to explain the fact that congested traffic tends to fluctuate, e.g., stop-and-go traffic, rather than remain at a single, relatively stable congested state.