An enhanced 0-1 mixed integer LP formulation for the traffic signal problem

An enhanced 0-1 mixed integer linear programming formulation is proposed for the traffic signal optimization problem based on the cell transmission model. The formulation has several new features that are unavailable in other existing models. The formulation handles physical queues, the number of stops, fixed or dynamic cycle length and splits, and lost time. The unintended vehicle holding problem, common in many existing analytical models, is eliminated in the proposed formulation. The formulation can be used for developing strategies for adaptive traffic control systems. Since the formulation is exact, it can also be used as a benchmark for examining the convergence behavior of existing heuristic algorithms based on the genetic algorithm, fuzzy logic, neural network or other approaches. The formulation can be solved using standard mathematical programming optimizers. The number of 0-1 integers used in the formulation is equal to the total number of intersections multiplied by the length of the entire optimization period.