Traffic signal optimization: combining static and dynamic models

TL;DR

This paper introduces a cyclically time-expanded network model for optimizing traffic assignment and signal control, demonstrating its realism and effectiveness through mathematical optimization and simulation on real-world data.

Contribution

It presents a novel cyclically time-expanded model that integrates traffic assignment and signal timing optimization, validated with simulations and real-world data.

Findings

The model accurately reproduces realistic travel times.

Mathematical programming effectively optimizes traffic signals.

Simulation confirms the model's practical applicability.

Abstract

In this paper, we present a cyclically time-expanded network model for simultaneous optimization of traffic assignment and traffic signal parameters, in particular offsets, split times, and phase orders. Since travel times are of great importance for developing realistic solutions for traffic assignment and traffic signal coordination in urban road networks, we perform an extensive analysis of the model. We show that a linear time-expanded model can reproduce realistic travel times especially for use with traffic signals and we verify this by simulation. Furthermore, we show how exact mathematical programming techniques can be used for optimizing the control of traffic signals. We provide computational results for real world instances and demonstrate the capabilities of the cyclically time-expanded by simulation results obtained with state-of-the-art traffic simulation tools.