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Seminar: Incremental Contingency Planning (for Mars Rover) 9/27; 3pm; GWC 387





Incremental Contingency Planning (for Mars Rover)

Speaker: David E. Smith
Head, Planning and Scheduling Group,
NASA AMES
Moffet Field, CA
http://wordbot.com/de2smith

Place & Time: GWC 487; Friday, September 27th, 2002; 3pm-->

There has been considerable work in AI on planning under uncertainty.
But this work generally assumes an extremely simple model of action that
does not consider continuous time and resources. These assumptions are
not reasonable for a Mars rover, which must cope with uncertainty about
the duration of tasks, the power required, the data storage necessary,
and its position and orientation.

In this talk, I present an approach to generating contingency plans
when the sources of uncertainty involve continuous quantities such as
time and resources. The approach involves first constructing a "seed"
plan, and then incrementally adding contingent branches to this plan in
order to improve utility. The challenge is to figure out the best places
to insert contingency branches. This requires an estimate of how much
utility could be gained by building a contingent branch at any given
place in the seed plan. Computing this utility exactly is intractable,
but I outline an approximation method that back propagates utility
distributions through a graph structure similar to that of a plan graph.

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As always with the AI Lab seminars, quality refreshments will be provided
in copious quantities ;-)