One of the major problems in urban sites is a continuous high traffic load resulting in a growing number of congestions. Urban traffic control systems have been developed to reduce the congestion level. They basically influence the traffic flow by means of dynamic signal control. In recent research projects rerouteing as an additional control method has been evaluated. In this paper a new approach for a tight integration by coordination of these two main control systems for inner urban traffic is presented. It consists of a hierarchical system architecture making use of a complete modular structure. This allows for the reuse of existing signal control and automatic rerouteing systems. It even makes it unnecessary to change anything in the remaining system if it is chosen to change a module, as long as it fits to the general requirements of the system. (A)
Abstract