A Derivative-based Control Method for Dynamic Traffic

摘要

Recently, Lo (1999, 2001) developed a cell-based dynamic signal control formulation designated as Dynamic Intersection Signal Control Optimization (DISCO). DISCO considers the entire range of the Fundamental Diagram by encapsulating the Cell-Transmission Model (CTM). To determine an optimal timing plan, one may either solve the mixed-integer program directly or develop a quasi-optimal solution approach based on Genetic Algorithm. Lo et al (2001) shows that DISCO outperformed TRANSYT by more than 30% in terms of overall delay reduction when applied to Hong Kong network scenarios. However, both approaches require extensive computational effort. To rectify this shortcoming, this study develops a derivative-based method, combined with Frank-Wolfe's convex combination algorithm to determine an optimal timing plan. The derivatives are derived using Newell's three-point detector approach. A simple example is included to illustrate the approach.