Abstract
Most practical work on AI planning systems during the last fifteen years has been based on Hierarchical Task Network (HTN) decomposition, but until now, there has been very little analytical work on the properties of HTN planners. This paper describes how the complexity of HTN planning varies with various conditions on the task networks, and how it compares to STRIPS-style planning.
Similar content being viewed by others
References
F. Baader, A formal definition for expressive power of knowledge representation languages, in:Proceedings of the 9th European Conference on Artificial Intelligence (Pitman, Stockholm, Sweden, Aug. 1990).
T. Bylander, Complexity results for planning,IJCAI-91 (1991).
D. Chapman, Planning for conjunctive goals,Artificial Intelligence 32 (1987) 333–378.
M. Drummond, Refining and extending the procedural net, in:Proc. IJCAI-85 (1985).
K. Erol, D. Nau and V.S. Subrahmanian, Complexity, decidability and undecidability results for domain-independent planning,Artificial Intelligence (to appear). A more detailed version is available as Tech. Report CS-TR-2797, UMIACS-TR-91-154, SRC-TR-91-96, University of Maryland, College Park, MD (1992).
K. Erol, J. Hendler and D. Nau, Semanties for hierarchical task network planning, Technical Report CS-TR-3239, UMIACS-TR-94-31, Computer Science Dept., University of Maryland (March 1994).
R.E. Fikes and N.J. Nilsson, STRIPS: a new approach to the application of theorem proving to problem solving,Artificial Intelligence 2(3/4) (1971).
Hopcroft and Ullman,Introduction to Automata Theory, Languages and Computation (Addison-Wesley, California, 1979).
S. Kambhampati and J. Hendler, A validation structure based theory of plan modification and reuse,Artificial Intelligence (May 1992).
A.L. Lansky, Localized event-based reasoning for multiagent domains,Computational Intelligence Journal (1988).
E.D. Sacerdoti, The nonlinear nature of plans, in:Proceedings of IJCAI (1975) pp. 206–214.
A. Tate, Generating project networks, in:Proceedings of IJCAI (1977) pp. 888–889.
S.A. Vere, Planning in time: windows and durations for activities and goals,IEEE Transactions on Pattern Analysis and Machine Intelligence PAMI 5(3) (1983) 246–247.
D. Wilkins,Practical Planning: Extending the Classical AI Planning Paradigm (Morgan-Kaufmann, 1988).
Q. Yang, Formalizing planning knowledge for hierarchical planning,Computational Intelligence 6 (1990) 12–24.
Author information
Authors and Affiliations
Additional information
This work was supported in part by NSF Grant NSFD CDR-88003012 to the Institute for Systems Research, and NSF grant IRI9306580 and ONR grant N00014-91-J-1451 to the Computer Science Department.
Rights and permissions
About this article
Cite this article
Erol, K., Hendler, J. & Nau, D.S. Complexity results for HTN planning. Ann Math Artif Intell 18, 69–93 (1996). https://doi.org/10.1007/BF02136175
Issue Date:
DOI: https://doi.org/10.1007/BF02136175