8 research outputs found
HDDL 2.1: Towards Defining a Formalism and a Semantics for Temporal HTN Planning
Real world applications as in industry and robotics need modelling rich and
diverse automated planning problems. Their resolution usually requires
coordinated and concurrent action execution. In several cases, these problems
are naturally decomposed in a hierarchical way and expressed by a Hierarchical
Task Network (HTN) formalism.
HDDL, a hierarchical extension of the Planning Domain Definition Language
(PDDL), unlike PDDL 2.1 does not allow to represent planning problems with
numerical and temporal constraints, which are essential for real world
applications. We propose to fill the gap between HDDL and these operational
needs and to extend HDDL by taking inspiration from PDDL 2.1 in order to
express numerical and temporal expressions. This paper opens discussions on the
semantics and the syntax needed for a future HDDL 2.1 extension.Comment: 5 pages, International Workshop of Hierarchical Planning (ICAPS),
202
Grounding of HTN Planning Domain
International audienceMany Artificial Intelligence techniques have been developed for intelligent and autonomous systems to act and make rational decisions based on perceptions of the world state. Among these techniques, HTN (Hierarchical Task Network) planning is one of the most used in practice. HTN planning is based on expressive languages allowing to specify complex expert knowledge for real world domains. At the same time, many preprocess-ing techniques for classical planning were proposed to speed up the search. One of these technique, named grounding, consists in enumerating and instantiating all the possible actions from the planning problem descriptions. This technique has proven its effectiveness. Therefore, combining the expressiveness of HTN planning with the efficiency of the grounding preprocessing techniques used in classical planning is a very challenging issue. In this paper, we propose a generic algorithm to ground the domain representation for HTN planning. We show experimentally that grounding process improves the performances of state of the art HTN planners on a range of planning problems from the International Planning Competition (IPC)