Ontological support for modelling planning knowledge

This paper describes the conceptual model underlying the Knowledge Engineering Web Interface (KEWI) which primarily aims to be used for modelling planning tasks in a semi-formal framework. This model consists of three layers: a rich ontology, a model of basic actions, and more complex methods. It is this structured conceptual model based on the rich ontology that facilitates knowledge engineering. The focus of this paper is to show how the central knowledge model used in KEWI differs from a model directly encoded in PDDL, the language accepted by most existing planning engines. Specifically, the rich ontology enables a more concise and natural style of representation, including function terms as object references. For operational use, KEWI automatically generates PDDL. Experiments show that the generated PDDL can be processed by a planner without incurring significant drawbacks.