Hierarchical efficient route planning in road networks

In this paper, a hierarchical route planning using Q value-based Dynamic Programming has been proposed. In the proposed method, a road network is divided into several subnetworks. A high-level road network is built with origin, destination and border intersections of subnetworks and the optimal traveling time between them are used to find the route from origin to destination using Q value-based Dynamic Programming. Additionally, a new re-routing method is proposed when the traveling times of sections are changed, where the border intersections in the route are kept fixed and only the route between them are re-optimized. The efficiency of the hierarchical method and accuracy of the re-routing method is evaluated using the Kitakyushu road network. The simulation results show that the hierarchical method is efficient to perform the search of a large number of routes. In addition, the results also show that the proposed re-routing method gives the route with the traveling time very near to the optimal traveling time.