Lessons Learned from the CYK Algorithm for Parsing-based Verification of Hierarchical Plans

Verification of hierarchical plans deals with the problem of whether an action sequence is causally consistent and can be obtained by a decomposition of a goal task. This second sub-problem (finding the decomposition) makes the verification problem NP-hard. The task decomposition structure is very c...

Full description

Saved in:
Bibliographic Details
Main Authors: Simona Ondrčková, Roman Barták, Pascal Bercher, Gregor Behnke
Format: Article
Language:English
Published: LibraryPress@UF 2023-05-01
Series:Proceedings of the International Florida Artificial Intelligence Research Society Conference
Subjects:
Online Access:https://journals.flvc.org/FLAIRS/article/view/133196
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Verification of hierarchical plans deals with the problem of whether an action sequence is causally consistent and can be obtained by a decomposition of a goal task. This second sub-problem (finding the decomposition) makes the verification problem NP-hard. The task decomposition structure is very close to a parsing tree of context-free grammar (CFG). Recently, the CFG-parsing algorithm by Cocke–Younger–Kasami (CYK) has been modified to verify hierarchical plans efficiently. Despite being fast, the algorithm can only handle totally-ordered planning domains. In this paper, we ask whether the ideas from the CYK algorithm can be extended to a more general parsing-based approach that covers all planning domains, i.e., including partially ordered ones. More specifically, we study the effect of modifying the domain model by limiting the number of sub-tasks in decomposition methods to two and the effect of changing the parsing strategy.
ISSN:2334-0754
2334-0762