MIT16_410F10_lec07b - Activity Planning and Execution...

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Activity Planning and Execution:
Introduction to Operator-based Planning
Brian C. Williams
16.410-13
September 29 th , 2010
Slides draw upon
material from:
Dr. David Smith,
NASA Ames Research
Center
Assignments
• Remember:
– Problem Set #3: Analysis and Constraint Programming,
due today Wednesday, Sept. 29
th
, 2010.
– Problem Set #4: Constraint Satisfaction and Activity
Planning, out today, due Wednesday, October 6 th , 2010.
• Reading:
– Today: Operator-based Planning [AIMA] Ch. 10.
! Graph Plan, " by Blum & Furst.
– Monday: Advanced Planning [AIMA] Ch. 11.
Brian Williams, Fall 10 2

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Monitors
Autonomous
Agents
Command dispatch
Fault protection
Attitude control
Mission Goal Scenario
Self-commanding
Self-diagnosing
Self-repairing
RECOVERY
PLANNING
EXECUTION
Commanded in terms of
• Mission goals
• Engineering goals
Operator-based Planning
• Input
– Set of world states
– Action operators
• Fn: world-state world-state
– Initial state of world
– Goal
• A partial state
(set of world states)
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a
a
a
north11
north12
W
0
W
2
W
1
Output
Sequence of actions that is
Complete: Achieve goals
Consistent: No negative
side-effects

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Operators in STRIPS
Representation
Turn (?target):
Pre: Pointing (?direction),
?direction ?target
Eff: ¬ Pointing (?direction),
Pointing (?target)
Outline
• Example: DS1 and MER Mission-Planning
• Overview of Operator-based Planning
• Graph Plan

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Outline
•