The document discusses several issues related to implementing condition-based maintenance (CBM) and prognostics and health management (PHM) programs, including: 1) Performing a thorough risk assessment using techniques like FMECA is important to understand how a system can fail and inform sensor placement and diagnostic rule development. 2) Model-based failure analysis considering failure dependencies is better than spreadsheet-based FMECA for knowledge retention and risk assessment. 3) Clear definitions of failure concepts and taxonomies are needed to improve understanding of risk assessments. 4) Diagnostic rules and sensor selection should be based on dependencies between failure modes revealed through risk assessments.

1. The PHM X Technology – Risk minimization Jacek S. Stecki PHM Technology X PHM - Prognostics and Health Management

4. Integrated Logistics Support Assuring continued operation and functioning of the systems

9. PHM Paradigm (Joint Strike Fighter F35)

14. CBM/PHM - what are we dealing with? FMECA Production Losses Reliability Condition monitoring Prognostics Maintenance Detection Diagnosis Algorithms Failure modes Faults Simulation Downtime Testing Risk Minimization $$$$$$$! Training Fall-back Analysis Hazards Safety Training FMECA Standards Training FMECA Reliability Diagnosis Sensor fusion Failure modes BIT Training FMECA Fault Tree ROI FMECA Reliability Sensors Diagnosis Education Failure modes Training Training FMECA Functional Analysis Training Education Sensor fusion Sensor fusion Artificial intelligence Maintainability Availability

15. Identifying Risk

20. Risk Assessment FMECA Failure Modes Effects Criticality Analysis What effect does the failure have ? Criticality Analysis of failure Possible Failures FM ECA FM E C A FME CA

22. Modeling Failure

23. Modelling of failure

24. Dependencies Modelling

25. All faults are enumerated. Transient and steady-state responses to faults are identified Fault propagation - dependability

26. Failures - Symptoms/Syndromes

27. Taxonomy problems

28. Sensor selection

30. Interaction between MAD and CBM/PHM Layers at Design Stage MAD – Maintenance aware Design

32. MADe software

33. RR250 Engine Lubrication System

34. Jet Engine Lubrication System Model

35. Model of pump

36. Define Component Structure

37. Define Component Functions

38. Define Physical Failures

39. Propagate Functional Failures >> Dependency

40. Assess Criticality

41. Produce FMEA/FMECA Report

42. Assess hardware Reliability

43. Fault Tree

44. Define Sensors Locations

45. Select sensors and generate diagnostic rules

46. CAD concurrent with MADe

55. Taxonomy issues