ECAI 2004 Conference Paper

[PDF] [full paper] [prev] [tofc] [next]

Utilizing Volatile External Information During Planning

Tsz-Chiu Au, Dana Nau, V.S. Subrahmanian

Most AI-planning research has assumed that a planner has all the information it needs at the start of the planning process---but in many practical planning situations, planners may need to get information from external sources (database systems, CAD systems, human users, web services, etc.) during the planning process. The lag time for such queries can slow down the planning considerably. Furthermore, the information returned by the queries may be volatile: it may change before planning is completed, necessitating revisions to the plan. We describe the following: 1. Wrappers that may be placed around conventional (isolated) planners. The wrapper replaces some of the planner's memory accesses with queries to external information sources. When appropriate, the wrapper will automatically backtrack the planner to a previous point in its operation. 2. Query-management strategies for wrappers. These dictate when to issue queries, and when/how to backtrack the planner. We describe several provably sound strategies, and describe conditions under which they are complete. 3. Mathematical analysis and experimental tests. Our results show conditions under which different query management strategies are preferable, and demonstrate that certain kinds of planning paradigms are more suited than others for planning with volatile information.

Keywords: Planning

Citation: Tsz-Chiu Au, Dana Nau, V.S. Subrahmanian: Utilizing Volatile External Information During Planning. In R.López de Mántaras and L.Saitta (eds.): ECAI2004, Proceedings of the 16th European Conference on Artificial Intelligence, IOS Press, Amsterdam, 2004, pp.647-651.

[prev] [tofc] [next]

ECAI-2004 is organised by the European Coordinating Committee for Artificial Intelligence (ECCAI) and hosted by the Universitat Politècnica de València on behalf of Asociación Española de Inteligencia Artificial (AEPIA) and Associació Catalana d'Intel-ligència Artificial (ACIA).