Our research concerns formal, expressive, objectcentred languages and tools for use in engineering domains for planning applications. In this paper we extend our recent work on an object-centred language for encoding precondition planning domains to a language called OCLh, designed for HTN planning. Domain encodings for HTN planners are particularly troublesome, because they tend to be used in ...

Casting planning problems as propositional satlsfiability problems has recently been shown to be an effective way of scaling up plan synthesis. Until now, the benefits of this approach have only been utUized in primitive action-based planning models. Motivated by the conventional wisdom in the planning community about the effectiveness of hierarchical task network (HTN) planning models, in this...

Stigmergy, usually used on simple problems, can be applied to more complex ones by encoding them in the agents’ environment. We show how stigmergic agents can plan over a hierarchical task network, a resource-oriented dialect of the TÆMS language. Our results reveal an important distinction among HTN’s.

Although several approaches have been developed for planning in nondeterministic domains, solving large planning problems is still quite difficult. In this work, we present a novel algorithm, called YoYo, for planning in nondeterministic domains under the assumption of full observability. This algorithm enables us to combine the power of search-control strategies as in Planning with Hierarchica...

In a dynamic environment, even if an agent makes a plan to obtain a goal, the environment might change while the agent is executing the plan. In that case, the plan, which was initially valid when it was made, might later become invalid. Furthermore, in the process of replanning, it is necessary to take into account the side effects of actions already executed . To solve this problem, we have p...

It is widely believed, that the expressivity of STRIPS and STRIPS-like planning based on actions is generally lower than the expressivity of Hierarchical Task Network (HTN) and HTN-like planning, based on hierarchical decomposition. This would mean that a HTN-like planner can generally solve more domains than a STRIPS-like planner with the same extensions. In this paper, we show that both appro...

Course generation automatically assembles courseware adapted to the learner’s competencies and learning goals. Previous course generators offered only a limited representation a pedagogical knowledge and did not take full advantage of service-oriented architectures. This dissertation proposes a course generation framework (called Paigos) that enables the formalization and application of complex...

In this paper we describe work in progress that aims to develop a domain-independent tool set which supports the creation and analysis of domain descriptions and plans containing continuously changing processes, instantaneous events, and actions. The tools described are (i) a life history editor that enables a designer to create a domain description diagrammatically, automatically generating mu...

In this paper, we present the modelling of a domain of argumentation-based negotiation with scarce resources so that Hierarchical Task Network planning can be used for finding appropriate strategies for the negotiating agents. In our modelling, the agents justify their positions on interactions throughout the course of a negotiation episode, and such justifications are taken into account in fut...

SIADEX is an integrated framework to support decision making during crisis episodes by providing realistic temporally annotated plans of action. The main component of SIADEX is a forward state-based HTN temporal planner.