HiTi graph model of topographical road maps in navigation systems

In navigation systems, a primary task is to compute the minimum cost route from the current location to the destination. One of the major problems for navigation systems is that a significant amount of computation time is required to find a minimum cost path when the topographical road map is large. Since navigation systems are real time systems, it is critical that the path be computed while satisfying a time constraint. We propose a new graph model named HiTi (hierarchical multi graph model), for efficiently computing an optimal minimum cost path. Based on HiTi graph model, we propose a new single pair minimum cost path algorithm. We empirically show that our proposed algorithm performs far better than the traditional A* algorithm. Further, we empirically analyze our algorithm by varying both edge cost distribution and hierarchical level number of HiTi graphs.