Reliability assessment and prediction system and method for implementing the same

• US 20020078403A1
• Filed: 01/18/2001
• Published: 06/20/2002
• Est. Priority Date: 01/18/2000
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Johnson, Bruce G., Musil, Leon, Gullo, Louis J.
• Granted Patent: US 6,684,349 B2
• Time in Patent Office: Days
• US Class Current: 714/37
• CPC Class Codes: G06F 11/008 Reliability or availability analysis

Abstract

A system and method for reliability assessment and prediction of end items is provided herein. A reliability assessment program (RAP) in accordance with the present invention provides a reliability assessment of the new equipment and/or parts designed for in-field use by assessing the similarities and differences between the new equipment and the predecessor equipment. Predecessor end item field failure data is collected and analyzed to compare the degree of similarity between the predecessor fielded end item and the new design. Based on this comparison, an appropriate method of assessment is determined, for example, a similarity analysis process or a failure cause model. Both methods use models for comparison and generate an appropriate report expressing the failure rate prediction of the new design and/or the mean-time-between-failure (MTBF).

Claims

1. A reliability assessment program (RAP) system of the type including a plurality of data pertaining to a new end item and a database having a plurality of field failure history stored thereon, said field failure history pertaining to an in-field end item, said RAP system comprising:

an in-field data source for an in-field end item, said in-field data source having a data collecting system for gathering said field failure history;

a processor configured to receive said field failure history for said in-field end item and to receive said data pertaining to said new end item, said processor configured to determine a failure rate of said new end item in accordance with an assessment method selected upon a determination of a degree of similarity between said in-field end item and said new end item; and

an output interface configured to provide the failure rate in a readable format.

2. The RAP system of claim 1 wherein said in-field end item comprises an aircraft end item.

3. The RAP system of claim 1 wherein said processor being configured to calculate a failure rate of said in-field end item.

4. The RAP system of claim 3 wherein said in-field end item comprises a plurality of sub-assemblies.

5. The RAP system of claim 4 wherein said processor being configured to calculate a failure rate of each of said sub-assemblies and said failure rate of said infield end item comprising a summation of said failure rates of each of said subassemblies.

6. The RAP system of claim 5 wherein said failure rate of said in-field end item is stored on said database.

7. The RAP system of claim 1 wherein said degree or similarity comprises a numerical percentage representing an overall assessment of similarity between said in-field end item and said new end item.

8. The RAP system of claim 1 wherein said determination of a degree of similarity comprises a threshold level of similarity.

9. The RAP system of claim 1 comprising two assessment methods.

10. The RAP system of claim 9 comprising a similarity analysis method and a failure cause model method, if said degree of similarity meets or exceeds said threshold level, then said similarity analysis method is selected.

11. The RAP system of claim 1 wherein said new end item comprises a plurality of sub-assemblies and said failure rate of said new end item comprises a summation of a failure rate of each of said sub-assemblies.

12. The RAP system of claim 10 wherein said similarity analysis method comprises a plurality of levels wherein at least one of said levels is used to compare said in-field end item with said new end item in order to determine said failure rate of said new end item.

14. The reliability assessment and prediction system of claim 13 wherein said data collection means comprises a software tool capable of accessing a database having said in-service field failure data stored thereon.

15. The reliability assessment and prediction system of claim 14 wherein said software tool being configured to determine if said database includes an in-service end item which is substantially similar to said new end item.

16. The reliability assessment and prediction system of claim 13 wherein said assessment means comprises a similarity analysis method and a failure cause model method.

18. The method for a reliability assessment and a failure rate prediction of claim 17 wherein said collecting of said in-service field failure data comprises the steps of:

recording said in-service field failure data in a retrievable database;

accessing said in-service field failure data to determine if said predecessor end item is similar to said new design end item;

verifying said in-service field failure data for accuracy; and

determining whether said in-service field failure data is relevant.

19. The method for a reliability assessment and a failure rate prediction of claim 18 wherein said new design end item comprises an aircraft end item and said collecting step further comprises collecting field flight hour data.

20. The method for a reliability assessment and a failure rate prediction of claim 17 further comprising the step of calculating a failure rate of said predecessor end item using said in-service field failure data.

21. The method for a reliability assessment and a failure rate prediction of claim 20 wherein said predecessor end item comprises a plurality of sub-assemblies and said calculating a failure rate of said predecessor end item comprises calculating a failure rate for each sub-assembly.

22. The method for a reliability assessment and a failure rate prediction of claim 21 further comprising the steps of:

summing the failure rates from each sub-assembly; and

compensating for disconnects occurring when the summing step does not equal said failure rate of said predecessor end item.

23. The method for a reliability assessment and a failure rate prediction of claim 17 further comprising the step of generating a report expressing said failure rate prediction.

24. The method for a reliability assessment and a failure rate prediction of claim 23 wherein said step of generating a report comprises expressing a mean-time-between-failure (MTBF).

25. The method for a reliability assessment and a failure rate prediction of claim 17 further comprising the step of assessing said new design end item to gather a plurality of new design data.

26. The method for a reliability assessment and a failure rate prediction of claim 25 wherein said assessing step comprises the steps of:

determining a parts list of said new design end item;

characterizing a plurality of attributes of said new design end item; and

determining a function of said new design end item.

27. The method for a reliability assessment and a failure rate prediction of claim 17 further comprising the step of computing said degree of similarity between said predecessor end item and said new design end item.

28. The method for a reliability assessment and a failure rate prediction of claim 27 wherein said computing step comprises the steps of:

quantifying an impact of said similarities and differences; and

based on the quantifying step, computing a numerical percentage of similarity representing said degree of similarity between said predecessor end item and said new design end item.

29. The method for a reliability assessment and a failure rate prediction of claim 17 further comprising the step of querying whether said degree of similarity meets a threshold level of similarity, said querying step performed prior to said determining step.

30. The method for a reliability assessment and a failure rate prediction of claim 17 wherein said determining step comprises determining between two methods of assessment.

31. The method for a reliability assessment and a failure rate prediction of claim 17 wherein said calculating step comprises use of a physical model category for comparison between said predecessor end item and said new design end item.

32. The method for a reliability assessment and a failure rate prediction of claim 17 wherein said determining step determines a similarity analysis method of assessment based on a high degree of similarity.

33. The method for a reliability assessment and a failure rate prediction of claim 30 wherein said determining step comprises determining between a similarity analysis method and a failure cause model method.

13. A reliability assessment and prediction system comprising:

a data collection means for gathering a plurality of in-service field failure data for an in-service end item;

a data collection means for gathering a plurality of design data for a new end item;

a processing means for calculating a failure rate for said in-service end item using said in-service field failure data, for comparing said in-service field failure data for said in-service end item to said design data for said new end item, and for determining a degree of similarity between said in-service end item and said new end item;

an assessment means for calculating a failure rate prediction of said new end item; and

a reporting means for generating a report expressing the failure rate prediction.

17. A method for a reliability assessment and a failure rate prediction of a new design end item, said method comprising the steps of:

collecting a plurality of in-service field failure data pertaining to a predecessor end item;

comparing said in-service data to a plurality of new design data pertaining to said new design end item;

identifying a plurality of similarities and differences between said in-service data and said new design data;

determining a method of assessment based on a degree of similarity between said predecessor end item and said new design end item; and

calculating said failure rate prediction of said new design end item according to said method of assessment.