MVILAIN@G.BBN.COM (Marc Vilain) (02/04/88)
BBN Science Development Program
AI Seminar Series Lecture
SYNTHESIZING PLANS THAT CONTAIN ACTIONS
WITH CONTEXT-DEPENDENT EFFECTS
Edwin P.D. Pednault
AT&T Bell Laboratories
Holmdel, New Jersey
(!vax135!epdp@UCBVAX.BERKELEY.EDU)
BBN Labs
10 Moulton Street
3rd floor large conference room
10:30 am, Tuesday February 9th
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* note unusual room *
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Conventional domain-independent planning systems have typically excluded
actions whose effects depend on the situations in which they occur,
largely because of the action representations that are employed.
However, some of the more interesting actions in the real world have
context-dependent effects. In this talk, I will present a planning
technique that specifically addresses such actions. The technique is
compatible with conventional methods in that plans are constructed via
an incremental process of introducing actions and posting subgoals. The
key component of the approach is the idea of a secondary precondition.
Whereas primary preconditions define executability conditions of actions,
a secondary precondition defines a context in which an action produces a
desired effect. By introducing and then achieving the appropriate
secondary preconditions as additional subgoals to actions, we ensure
that the actions are carried out in contexts conducive to producing the
effects we desire. The notion of a secondary preconditions will be
defined and analyzed. It will also be shown how secondary preconditions
can be derived in a general and domain-independent fashion for actions
specified in ADL, a STRIPS-like language suitable for describing
context-dependent effects.
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