MPLP: Massively Parallelized Lazy Planning

Lazy search algorithms have been developed to efficiently solve planning problems in domains where the computational effort is dominated by the cost of edge evaluation. The current approaches operate by intelligently balancing computational effort between searching the graph and evaluating edges. However these algorithms are designed to run as a single process and do not leverage the multi-threading capability of modern processors. In this work we propose a massively parallelized, bounded suboptimal, lazy search algorithm (MPLP) that harnesses modern multi-core processors. In MPLP, searching of the graph and edge evaluations are performed completely asynchronously in parallel, leading to a drastic improvement in planning time. We validate the proposed algorithm in two different planning domains: motion planning for a humanoid navigation and task and motion planning for a robotic assembly task. We show that MPLP outperforms the state of the art lazy search as well as parallel search algorithms.