Modern traffic control systems in state-space approach

Abstract

The paper deals with the modern system and control theoretical approach of road traffic automation. Classical road traffic modelling takes the special characteristics into consideration, which mathematical equations could be cast into a general state-space form of dynamical systems. The first section of the paper introduces the state-space model of urban intersections and of freeway traffic flow; the paper also shows the simulation results of these models. Based on these state-space models one could apply the results of the modern and post-modern system- and control theory; one could develop so called observers and optimal control strategies for road traffic systems. The second part of the paper negotiates the results in estimation procedures of road traffic variables. These procedures multiply the available data set which could be used through the controller design procedure. The third part of the paper shows the control problems of road traffic systems. First a simply urban intersection control then the problem of coordinated intersection control has been investigated. The simulation results are quite promising in both cases. Finally the problem of freeway traffic control has been discussed, the paper shows the simulation results of how the coordinated freeway control could prevent traffic breakdown.