Http://www.research.att.com/~kautz/talks/

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• Http//www.research.att.com/kautz/talks/

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The Role of Optimization andDeduction in
Reactive Systems

• P. Pandurang Nayak
• NASA Ames Research Center
• Brian C. Williams
• MIT

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Autonomous Mars Airplane
courtesy NASA Ames
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The Cost of Autonomy Cassini

• 1 billion
• 7 years to build
• 150 - 300 ground operators

• 100 million
• 2 year build
• 0 ground ops

Cassini Maps Titan
courtesy JPL
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Started January 1996 Launch October 15th,
1998 Experiment May 17-21
courtesy JPL
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Remote Agent
Mission Manager
Planner Scheduler
Procedural Executive
ESL
Monitors
AMES / JPL
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Model-based Execution as a kind of Stochastic
Optimal Controller
Models
Goals
mode reconfiguration
s(t)
Controller
mode identification
?(t)
o(t)
Plant
s (t)
f
g
Livingstone

• Indirect sensing and control.
• Probability, optimality, logic deduction.

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OPSAT
Check Consistency
Best First Agenda
Optimal feasible solutions
ITMS
Kernel assignments
Checked solutions
generate successors
conflict database

• Generate Best Kernel Assignments
• Generate minimal covering of conflicts, in best
  first order.
• Compact encoding grows agenda linearly with
  checked states
• Test SAT
• Unit propagation dominates, ITMS efficiently
  tracks changes.

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Remote Agent Experiment
See rax.arc.nasa.gov

• May 17-18th experiment
• Generate plan for course correction and thrust
• Diagnose camera as stuck on
• Power constraints violated, abort current plan
  and replan
• Perform optical navigation
• Perform ion propulsion thrust
• May 21th experiment.
• Diagnose faulty device and
• Repair by issuing reset.
• Diagnose switch sensor failure.
• Determine harmless, and continue plan.
• Diagnose thruster stuck closed and
• Repair by switching to alternate method of
  thrusting.
• Back to back planning

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Remote Agent Experiment
See rax.arc.nasa.gov

• May 17-18th experiment
• Generate plan for course correction and thrust
• Diagnose camera as stuck on
• Power constraints violated, abort current plan
  and replan
• Perform optical navigation
• Perform ion propulsion thrust
• May 21th experiment.
• Diagnose faulty device and
• Repair by issuing reset.
• Diagnose switch sensor failure.
• Determine harmless, and continue plan.
• Diagnose thruster stuck closed and
• Repair by switching to alternate method of
  thrusting.
• Back to back planning

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Remote Agent Team Members

• Nicola Muscettola Ames
• Pandurang Nayak Ames
• Barney Pell Ames
• Chris Plaunt Apple
• Gregg Rabideau JPL
• Kanna Rajan Ames
• Nicolas Rouquette JPL
• Scott Sawyer LMMS
• Rob Sherwood JPL
• Reid Simmons CMU
• Ben Smith JPL
• Will Taylor Ames
• Hans Thomas Ames
• Michael Wagner 4th Planet
• Greg Whelan CMU
• Brian C. Williams Ames
• David Yan Stanford

• Douglas Bernard JPL
• Steve Chien JPL
• Greg Dorais Ames
• Julia Dunphy JPL
• Dan Dvorak JPL
• Chuck Fry Ames
• Ed Gamble JPL
• Erann Gat JPL
• Othar Hansson Thinkbank
• Jordan Hayes Thinkbank
• Bob Kanefsky Ames
• Ron Keesing Ames
• James Kurien Ames
• Bill Millar Ames
• Sunil Mohan Formida
• Paul Morris Ames

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Outline

• Deep Space One and Remote Agent
• Model-based Execution
• OPSAT and the ITMS
• Model-based Reactive Planning
• Space Robotics