Motorway traffic surveillance and control

The available capacity of motorway networks is degraded in presence of traffic congestion, leading to reduced throughput, increased pollution and higher accident risk. The traffic flow efficiency may be increased via suitable application of several control measures, such as ramp metering, driver information, route guidance, variable speed limits and further link control measures. The paper presents a macroscopic traffic flow model along with selected validation results, followed by an overview of some generic traffic surveillance methods and control strategies for motorway networks. Limited simulation and field results demonstrating the efficiency of the presented methods are also provided.