Localized Planning With Diversified Plan Construction Methods

This paper describes COLLAGE, a planner that utilizes a variety of non-traditional methods for plan construction within a partitioned or localized reasoning framework. The COLLAGE domain representation and plan construction methods are based on the use of action-based constraints. Not only do such constraints yield highly natural domain encodings, but they are also associated with cost-effective plan construction methods. The additional use of domain structure to partition the reasoning space and guide planning search likewise results in more efficient planning. COLLAGENS unconventional approach to planning is motivated by a specific target domain class: domains with parallel activities that require complex forms of coordination. We describe the design decisions underlying the COLLAGE approach in the context of a novel characterization of planning: a six-dimensional planning feature space. We also discuss how this six-dimensional space can serve a larger role in the planning community as a framework for comparing planning techniques, enhancing communication between researchers, elucidating ternfinological difficulties, and clarifying the relationship between a domain's characteristics and its most suitable planning technique.