Improving intersection capacity considering dilemma zone problem based on vehicle-to-infrastructure communications

Dilemma zone problem describes vehicles trapped in the road segment at the signalized intersection where drivers hard make accurate decisions for next movements. Such phenomenon can easily trigger traffic accidents or congestion, eventually, which likely decreases intersection capacity and also increases traffic pressure. How dose the issue evolve under Cooperative Vehicles Infrastructure Systems (CVIS)? In this paper, an optimization method is proposed to reduce the dilemma zone for enhancing the traffic capacity and safety of signalized intersections, which is based on the real-time traffic information by vehicles-to-infrastructure (V2I) communication. The problem is formulated as a Binary Mixed Integer Linear Program (BMILP) that can be solved by a standard branch-and-bound routine. A set of constraints is designed to ensure feasibility and safety of movements for connected vehicles. Numerical experiments show the capacity has a different degree of increase with the market penetration rate of connected vehicles increasing. Moreover, experimental results indicate the vehicle queue length at the signalized intersection reduces correspondingly.