A Fuzzy Approach to Reduce Delays at Signalized Road Intersections

In this paper a fuzzy approach is proposed to reduce delay at isolated intersections by using as indicator the intersection saturation degree. The proposed system combines fixed-duration cycle and fuzzy calculus to reduce the overall delay without giving too much penalty to some traffic streams. To obtain the intended goal, the green times are modified according to the measured traffic flow values and by using a fuzzy procedure. Measured traffic flows are considered as fuzzy quantities because of their uncertainty and/or imprecision. A test example is analysed to show the benefits of the fuzzy controlled intersection with respect to a crispy controlled one. The results show that the use of the fuzzy procedure reduces the total and average delay at the intersection by modifying the phase duration according to sampled traffic flows.