A methodology to design traffic signal controllers based on fuzzy logic

A methodology to design traffic signal controllers based on fuzzy logic is presented. Although there are many applications that use fuzzy logic to control traffic of vehicles at intersections, there is no uniform design procedure to help people, not familiar with this theory, to apply the methods. The purpose of the proposed design methodology is to overcome this limitation. The designed fuzzy controller uses existing traffic detectors to measure the number of vehicles at the intersection and decides how to change the traffic signals in order to minimize the average delay of vehicles. This fuzzy controller has a fixed structure composed of 125 rules. The only variation is the change in support for input fuzzy sets, which depends on implementation and current traffic situation. Simulation results showed that traffic controllers developed with the proposed methodology reduce the average delay of vehicles at intersections compared with conventional traffic control strategies.