Synthetic redundancy via prognostics

• US 8,201,424 B2
• Filed: 01/22/2009
• Issued: 06/19/2012
• Est. Priority Date: 01/22/2009
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Bodden, David S., Grube, William E., Hadden, Robert W., Clements, Nathan S.
• Primary Examiner(s): COSIMANO, EDWARD R
• Application Number:
  US12/358,124
• Publication Number:
  US 20100180418A1
• Time in Patent Office: 1,244 Days
• Field of Search: 734/321, 738/658, 738/659, 340/500, 340/540, 340/635, 340/653, 340/679, 702/1, 702/33, 702/34, 702/127, 702/182, 702/183, 702/184, 702/187, 702/189, 714/1, 714/47.1, 714/47.2, 714/47.3, 714/100
• US Class Current: 70/34
• CPC Class Codes: B64F 5/00 Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
• CPC Class Codes: Y10T 29/49721 with disassembling
• CPC Class Codes: Y10T 70/443 Single stem or shank

Abstract

An manufacturing method that uses synthetic redundancy to optimize equipment reliability, performance, weight, and cost. The manufacturing method identifies critical components, that would ordinarily require a redundant component to meet reliability and safety requirements, and replaces them with a single, non-redundant component. Safety and reliability is maintained by using prognostic health management to replace the non-redundant critical component prior to its failure. Verification techniques are used to ensure reliability requirements are being met.

Claims

1. A method for optimizing the design and operation of equipment, comprising:

identifying a redundant component;

replacing the redundant component with a single component;

determining a remaining useful life of the single component;

replacing the single component when the remaining useful life reaches a predetermined amount of time; and

calculating a statistical confidence level that the single component will be replaced prior to failure.

2. The method of claim 1, wherein the equipment comprises a vehicle.

3. The method of claim 1, wherein the statistical confidence level is based on a quantity of failed components and a quantity of replaced components.

4. The method of claim 1, wherein the predetermined amount of time is calculated to allow at least a predetermined percentage of failures.

5. The method of claim 1, wherein the mean time between failures of the single component is not greater than the mean time between failures of the redundant component.

6. The method of claim 1, further comprising:

determining a minimum statistical confidence level; and

determining a quantity of data required to verify the statistical confidence level, the quantity of data comprising the number of failures of the single component and the number of replacements of the single component.

7. The method of claim 1, wherein the remaining useful life is calculated by a computer attached to the equipment.

8. The method of claim 1, wherein the remaining useful life of the component is greater than a predetermined amount of time.

9. The method of claim 8, wherein the equipment comprises an aircraft and wherein the predetermined amount of time is greater than the length of one flight.

10. A program product stored on a computer readable medium that, when read by a computer, causes the computer to perform the operations of:

determining a remaining useful life of a non-redundant critical component, the critical component being installed on a piece of equipment;

ordering the replacement of the non-redundant critical component when the remaining useful life reaches a predetermined amount of time; and

calculating a statistical confidence level that the non-redundant critical component will be replaced prior to failure.

11. The program product of claim 10, wherein the determination of the remaining useful life of the non-redundant critical component comprises analysis of failure precursor data.

12. The program product of claim 11, wherein the mean time between failures of the non-redundant critical component is not greater than the mean time between failures of a redundant critical component, the redundant critical component performing the same operation as the non-redundant critical component.

13. The program product of claim 11, wherein the remaining useful life of the component is greater than a predetermined amount of time.

14. A computer implemented method of manufacturing a piece of equipment, the method comprising:

(a) identifying a critical component on a piece of equipment;

(b) building the piece of equipment, wherein the piece of equipment does not have a redundant component for the critical component;

(b) creating an algorithm that estimates a remaining useful life of the critical component;

(c) determining a maximum allowable failure rate for the critical component;

(d) replacing the critical component when the remaining useful life reaches a predetermined amount;

(e) determining an actual failure rate from the number of the critical components that fail prior to replacement and the number of the critical components that are replaced; and

(f) using the algorithm so long as the actual failure rate does not exceed the maximum allowable failure rate.

15. The method of claim 14, wherein the mean time between failures of the critical component is not less than the mean time between failures of a redundant critical component.

16. The method of claim 14, wherein the critical component comprises a sub-component of another critical component.

17. The method of claim 14, further comprising determining a minimum allowable failure rate.

18. The method of claim 14, wherein the piece of equipment comprises an aircraft.

19. The method of claim 14, wherein the piece of equipment is not a vehicle.

20. The method of claim 14, wherein and actual confidence level based on failure and replacement data is compared to a theoretical confidence level.