Investigating the Feasibility of Urban Link Travel Time Estimation Based on Probe Vehicle Data

From past several years, the interest to use probe vehicles for monitoring is growing. In this paper, vehicles equipped with GPS are used as traffic sensors to collect traffic data (speed, position and time stamps) on urban road network. A method developed by (Bruce Hellinga 2008) is adopted to decompose travel times collected by probe vehicles between two consecutive time stamps into individual links. The estimated link travel times are compared with travel times from video cameras. The results show that link travel times estimated using Hellinga's method deviate significantly from travel times measured by cameras, especially when there is congestion or vehicles need to wait for the red time on the intersection. From the measured travel time, we also notice that travel times on urban links are quite variable during different times of day. There seems no clear travel time pattern which put much challenge for the travel time estimation and prediction on the urban road network.