Signal Progression Model for Long Arterial: Intersection Grouping and Coordination

Signal progression has been proven as an effective way to improve the operational efficiency of traffic signals at local arterial corridors. Conventional two-way progression models have shown their promising in providing desirable green bandwidth to two-way through traffic along the arterial. However, they may not offer an effective progression plan when a long arterial contains many intersections. Under such condition, it is critical to divide the arterial corridor into a set of subgroups for progression design. Since progression effectiveness is significantly impacted by the way an arterial is decomposed, conducting arterial decomposition as a separated step may keep the result from optimality. To tackle this issue, a novel progressive model is developed to concurrently determine the arterial decomposition strategy and optimize the resulting signal progression plan within each subgroup. With an integrated control objective function, the proposed model can minimize the required number of subgroups while satisfying the operational need (i.e., a minimum bandwidth is required). Also, the proposed model is formulated with a mixed-integer-linear-programming technique that can guarantee a global optimal solution. A numerical example on a field arterial which consists of 15 signalized intersections has verified the effectiveness of the proposed model.