Markos Papageorgiou

The Need for Traffic Control

The emergence of traffic (i.e. many interacting vehicles using a common infrastructure) and subsequently traffic congestion (whereby demand exceeds the infrastructure capacity) have opened new innovation needs in the transportation area. The energy crisis in the 1970’s, the increased importance of environmental concerns, and the limited economic and physical resources are among the most important reasons why a brute-force approach (i.e., the continuous expansion of the available transportation infrastructure) cannot continue to be the only answer to the ever increasing transportation and mobility needs of modern societies. The efficient, safe, and less polluting transportation of persons and goods calls for an optimal utilization of the available infrastructure via suitable application of a variety of traffic control measures. This trend is enabled by the rapid developments in the areas of communications and computing, but it is quite evident that the efficiency of traffic control directly depends on the efficiency and relevance of the employed control methodologies. This chapter will provide an overview of advanced traffic control strategies for three particular areas: Urban road networks, freeway networks, and route guidance and information systems.