Intelligent highway by fuzzy logic: congestion detection and traffic control on multi-lane roads with variable road signs

Traffic control involves analysis of both detected traffic flow and environmental conditions. Due to individual behavior of traffic participants, and the inherent uncertainty of weather condition interpretations, a mathematical model can not fully describe traffic control problems. The paper discourses two aspects of a traffic management system for multi-lane highways with variable road signs. First, fuzzy logic is used to take into account the uncertainties of traffic data, and to detect traffic congestion in isolated road sections. Second, a traffic control approach using a fuzzy model based on experience is shown. Both approaches were implemented in an existing traffic control system of the B27, a state highway between Stuttgart city, Stuttgart airport, and Tuebingen. The paper compares the results of the new approach with the previous approach based on conventional control technology.