Path Planning with CPD Heuristics

Path Planning with CPD Heuristics

Massimo Bono, Alfonso E. Gerevini, Daniel D. Harabor, Peter J. Stuckey

Proceedings of the Twenty-Eighth International Joint Conference on Artificial Intelligence
Main track. Pages 1199-1205. https://doi.org/10.24963/ijcai.2019/167

Compressed Path Databases (CPDs) are a leading technique for optimal pathfinding in graphs with static edge costs. In this work we investigate CPDs as admissible heuristic functions and we apply them in two distinct settings: problems where the graph is subject to dynamically changing costs, and anytime settings where deliberation time is limited. Conventional heuristics derive cost-to-go estimates by reasoning about a tentative and usually infeasible path, from the current node to the target. CPD-based heuristics derive cost-to-go estimates by computing a concrete and usually feasible path. We exploit such paths to bound the optimal solution, not just from below but also from above. We demonstrate the benefit of this approach in a range of experiments on standard gridmaps and in comparison to Landmarks, a popular alternative also developed for searching in explicit state-spaces.
Keywords:
Heuristic Search and Game Playing: Heuristic Search
Robotics: Motion and Path Planning