A Rolling-horizon Quadratic-programming Approach to the Signal Control Problem in Large-scale Congested Urban Road Networks

The paper investigates the efficiency of a new signal control methodology, which offers a computationally feasible technique for real-time network-wide signal control in largescale urban traffic networks and is applicable also under congested traffic conditions. In this methodology, the traffic flow process is modeled by use of the so-called store-and-forward modeling paradigm. The overall problem of network-wide signal control is formulated as a constrained Quadratic-Programming problem, that aims at minimizing and balancing the link queues so as to minimize the risk of queue spillback. For the application of the proposed methodology in real time, the corresponding optimization algorithm is embedded in a rollinghorizon (model-predictive) control scheme. The control strategy’s efficiency and real-time feasibility is demonstrated and compared with the Linear-Quadratic approach taken by the signal control strategy TUC via their simulation-based application to the urban network of the city centre of Chania, Greece, under a number of different scenarios. INTRODUCTION In view of the imminent traffic congestion and lack of possibilities for infrastructure expansion in urban road networks, the importance of efficient signal control strategies, particularly under saturated traffic conditions, can hardly be overemphasized. It is generally believed that real1PhD Candidate, Dynamic Systems and Simulation Laboratory, Technical University of Crete, Chania, Greece, e-mail: {aboud,tasos}@dssl.tuc.gr 2Professor, Dynamic Systems and Simulation Laboratory, Technical University of Crete, Chania, Greece, email: [email protected] 3Assistant Professor, Dynamic Systems and Simulation Laboratory, Technical University of Crete, Chania, Greece, e-mail: [email protected]