Efficiently Handling Temporal Knowledge in an HTN Planner.

Abstract This paper presents some enhancements,in the temporal reasoning of a Hierarchical Task Network (HTN) planner, named SIADEX, that, up to authors knowledge, no other HTN planner has. These new,features include a sound partial order metric structure, deadlines, temporal landmarking,or synchronization capabilities built on top of a Simple Temporal Network and an efficient constraint propagation engine boosted by exploiting the causal structure of plans.