Revisiting shortest path algorithms for navigation systems

Abstract

Efficient shortest path algorithms are central to routing and navigation applications. However, finding the shortest path is often not adequate for urban sidewalk routes, as users of these applications may also be interested in alternative routes that, although slightly longer, have other desirable features and properties (i.e., accessibility, safety, comfort, and convenience). The k-shortest paths (KSP) represent an ordered list of the available alternative routes. Even though several KSP algorithms have been proposed, to our knowledge, there is no research considering all these issues. The purpose of this paper is to introduce a heuristic algorithm that uses a penalty method by increasing certain edge weights, to effectively search for the most accessible alternative paths for multi-route cases in navigation systems. We then present experimental results on finding the most accessible paths in pedestrian sections of the historical center of Thessaloniki city.