Unified Framework for Dynamic Traffic Assignment and Signal Control with Cell Transmission Model

Abstract

This research presents a unified framework for dynamic traffic assignment and signal control optimization. An objective function based on the system-optimal approach with an embedded traffic flow model (the cell transmission model) for dynamic traffic assignment was considered. The optimization model (a mixed-integer program) explicitly considered intersection delay and lost time from phase switches in addition to a traditional travel time objective. Two test networks were used to demonstrate the applicability of the proposed model. Results showed better performance of the models when they were compared with fixed-signal timing plans. The formulation of signal control design also accounted for the variation of cycle length, and results showed the variation of cycle lengths with different objective functions under different levels of congestion.