Laying the Foundations for Solving FOND HTN Problems: Grounding, Search, Heuristics (and Benchmark Problems)

Building upon recent advancements in formalising Fully Observable Non-Deterministic (FOND) Hierarchical Task Network (HTN) planning, we present the first approach to find strong solutions for HTN problems with uncertainty in action outcomes. We present a search algorithm, along with a compilation that relaxes a FOND HTN problem to a deterministic one. This allows the utilisation of existing grounders and heuristics from the deterministic HTN planning literature.