A Structural Complexity Analysis of Hierarchical Task Network Planning

Cornelius Brand; Robert Ganian; Fionn Mc Inerney; Simon Wietheger

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arXiv · 2401.14174

A Structural Complexity Analysis of Hierarchical Task Network Planning

Cornelius Brand·Robert Ganian·Fionn Mc Inerney·Simon Wietheger

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Abstract

We perform a refined complexity-theoretic analysis of three classical problems in the context of Hierarchical Task Network Planning: the verification of a provided plan, whether an executable plan exists, and whether a given state can be reached. Our focus lies on identifying structural properties which yield tractability. We obtain new polynomial algorithms for all three problems on a natural class of primitive networks, along with corresponding lower bounds. We also obtain an algorithmic meta-theorem for lifting polynomial-time solvability from primitive to general task networks, and prove that its preconditions are tight. Finally, we analyze the parameterized complexity of the three problems.

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Cornelius Brand, Robert Ganian, Fionn Mc Inerney, Simon Wietheger. 2024-01-25. A Structural Complexity Analysis of Hierarchical Task Network Planning. https://arxiv.org/abs/2401.14174

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