Optimal Sequenced Route Query Algorithm Using Visited POI Graph.

Trip planning methods including the optimal sequenced route (OSR) query become a critical role to find the economical route for a trip in location based services and car navigation systems. OSR finds the shortest route, starting from an origin location and passing through a number of locations or points of interest (POIs), following the prespecified route sequence. This paper proposes a fast optimal sequenced route query algorithm from the current position to the destination by unidirectional and bidirectional searches adopting an A* algorithm. An OSR query on a road network tends to expand an extremely large number of nodes, which leads to an increase in processing time. To reduce the number of node expansions, we propose a visited POI graph (VPG) to register a single found path that connects neighboring POIs. By using a VPG, duplicated node expansions can be suppressed. We also perform experiments to show the effectiveness of our method compared with a conventional approach, in terms of the number of expanded nodes and processing time.