Expressway Merge Assistance Method and Evaluation Based on Connected Vehicle Technology

Merge points on expressways are areas where a high number of accidents occur, and the connected vehicle technology is an effective means to improve the safety of these areas. In this study, a novel vehicle-coordinated control method is proposed to reduce the occurrence of security conflicts and congestion by providing early warning to the driver to adjust driving behavior. Vehicle conflicts are calculated and predicted based on the position and speed of vehicles that are located within the range of the communication by connected vehicle technology. First, the safety hazard of the merge area is analyzed. Second, the time range of the ramp truck to reach the merge area is calculated according to the characteristics of the truck. The speed range in which main road vehicles can reach the merge area is calculated using the same time range as that in the ramp vehicle. The optimal main road vehicle speed is recommended in the area to avoid possible conflicts in terms of safety and efficiency. Finally, the communication module of the system is developed using Vissim simulation software, and the effect of safety coordinated control is evaluated in terms of safety and traffic efficiency.