Effecting Analysis of Real-Time Traffic Guidance Information on Travel Time Reliability in a Connected Vehicle Environment

Travel time reliability (TTR) is an indicator of the level of service, especially the level of congestion experienced on it. Measures of TTR attempt to quantify the variability of the travel time of travelers’ experiences along the same route at different times. Traffic guidance is an alternative method to improve the TTR of road networks. However, the traditional traffic guidance based on variable message signs (VMS) encounters the delay effect of guidance information, which degrades the effectiveness of route guidance. The traffic guidance based on the connected vehicle (CV) is an effective method to enhance the TTR. Impact of real-time guidance information on TTR measures in a CV environment is analyzed. A traffic guidance algorithm based on CV technologies is proposed, and is validated by an integrated simulator for connected vehicle technologies. The simulation results show that traffic guidance has a significant influence on TTR in a CV environment. The increase of incident duration will produce the more serious traffic congestion, which results in the decline of TTR. A high penetration rate will improve the TTR of road networks. The proportion of non-CVs guided indirectly has also an influence on TTR, namely, a high following rate can help alleviate the impact of the incident on TTR.