A Fuzzy Dynamic Traffic Assignment Model for Real-Time Network Load Management

Traffic assignment has received much attention since 1950s'. Stochasticity, dynamic and fuzziness are three characteristics of traffic assignment. Since drivers always have no perfect information about traffic conditions, they choose their route based on perceived travel time. Traditional traffic assignment model can only capture the stochasticity and dynamic features of traffic assignment and cannot represent the fuzziness of driver's perception over travel time. Thus, we present a fuzzy dynamic traffic assignment (FDTA) model in this paper. By the definition of fuzzy perceived link travel time and fuzzy perceived path travel time, we use fuzzy shortest path algorithm to find the group of fuzzy shortest paths and assign traffic to each of them proportionally to their memberships. The proposed FDTA model can be used in the real-time network load management, especially with variable message signs.