Model-based Diagnosis Brian c。 WIllams 1641013 November 3rd 5th 2003 CourtesyNasa/Jpl-calTech.http://www.jplnasgov
10/03/03 copyright Brian Williams, 2003 1 Courtesy NASA/JPL-Caltech. http://www.jpl.nas.gov. Model-based Diagnosis Brian C. Williams 16.410-13 November 3rd & 5th 2003 Brian C. Williams, copyright 2000
Assignment Reading Model-based Diagnosis -Lecture notes Propositional Logic AlMA Chapter 6 Problem set Model-based Diagnosis implementation Propositional Logic 16.413: Hello World implementation Due Monday, November 17th 10/03/03 copyright Brian Williams, 2003
10/03/03 copyright Brian Williams, 2003 2 Assignment Reading Model-based Diagnosis – Lecture notes Propositional Logic AIMA Chapter 6 Problem Set Model-based Diagnosis implementation Propositional Logic 16.413: Hello World implementation Due Monday, November 17th
WORLD observations Plant actions sense act Diagnostic Agent AGENT Monitors diagnoses Repairs avoids Probes and tests Symptom-directed 10/03/03 copyright Brian Williams, 2003
10/03/03 copyright Brian Williams, 2003 3 sense P(s) WORLD observations actions AGENT Diagnostic Agent: • Monitors & Diagnoses • Repairs & Avoids • Probes and Tests Plant act Symptom-directed
Out line Model-based diagnosis Accounting for failures Explaining failures Handling unknown failures 10/03/03 copyright Brian Williams, 2003
10/03/03 copyright Brian Williams, 2003 4 Outline Model-based diagnosis Accounting for failures Explaining failures Handling unknown failures
Hidden Failures Require Reasoning ftom a Model Symptons. s e a STS-93 Engine p sensor high LOX le low GN&C det low thrust H2 level poss ly low Problem: Liquid hydrogen leak u5真 Effect: LH2 used to cool engine Engine runs hot Consumes more lOX ImagetakenfromNasa'swebsitehttp://www.nasa.gov
10/03/03 copyright Brian Williams, 2003 5 H i d d e n F a i l u r e s R e q u i r e R e a s o n i n g f r o m a M o d e l : S T S - 9 3 Symptoms: • Engine temp sensor high • LOX level low • GN&C detects low thrust • H2 level possibly low Problem: Liquid hydrogen leak Effect: • LH2 used to cool engine • Engine runs hot • Consumes more LOX Image taken from NASA’s web site: http://www.nasa.gov