Aircraft prognostics health system

• US 9,561,863 B2
• Filed: 12/19/2014
• Issued: 02/07/2017
• Est. Priority Date: 03/28/2014
• Status: Active Grant

• Current Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Original Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Inventors: Conrad, Kevin
• Primary Examiner(s): WONG, YUEN H
• Application Number:
  US14/577,229
• Publication Number:
  US 20150274312A1
• Time in Patent Office: 781 Days
• US Class Current: 1/1
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: B64D 45/00 Aircraft indicators or protectors not otherwise provided for camouflage F41H3/00
• CPC Class Codes: B64F 5/60 Testing or inspecting aircraft components or systems
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005

Abstract

According to one example embodiment, a method of assessing reliability of an aircraft component includes identifying, aboard an aircraft, a first probability of failure of the aircraft component installed on the aircraft. One or more measurements representative of at least one load applied against the aircraft component are received. Determined, aboard the aircraft, is a second probability of failure of the aircraft component based on the first probability of failure and the received one or more measurements representative of the at least one load applied against the aircraft component, the second probability of failure representing a probability of failure of the aircraft component after application of the at least one load.

Claims

1. A method of assessing reliability of a rotorcraft component, comprising:

identifying, by a processor, aboard a rotorcraft, a first probability of failure of the rotorcraft component installed on the rotorcraft, the first probability of failure representing a probability of failure of the rotorcraft component prior to application of at least one load;

receiving, by the processor, from one or more sensors installed on the rotorcraft, one or more measurements representative of the at least one load applied against the rotorcraft component;

determining, by the processor, aboard the rotorcraft, a second probability of failure of the rotorcraft component based on the first probability of failure and the received one or more measurements representative of the at least one load applied against the rotorcraft component, the second probability of failure representing a probability of failure of the rotorcraft component after application of the at least one load;

determining, by the processor, an equivalent life by assessing a cumulative damage of a change of a probability of failure and then converting the change of the probability of failure back into a time domain;

subtracting, by the processor, a calculated used-life damage index from a baseline model to identify a variance and then credit the variance towards a remaining useful life of the rotorcraft component so as to extend the remaining useful life of the rotorcraft component; and

adjusting, by the processor, at least one of an operation and a maintenance of the rotorcraft based on the remaining useful life.

2. The method of claim 1, wherein determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component comprises determining the second probability of failure during operation of the rotorcraft.

3. The method of claim 1, wherein the received one or more measurements further comprises an amount of time during which the at least one load was applied.

4. The method of claim 1, wherein the received one or more measurements further comprises a number of cycles for which the at least one load was applied.

5. The method of claim 1, wherein determining the second probability of failure of the rotorcraft component based on the first probability of failure and the received one or more measurements representative of the at least one load applied against the rotorcraft component comprises:

recognizing, using the received one or more measurements representative of the at least one load applied against the aircraft component, one or more regimes representative of an activity of the rotorcraft;

identifying at least one estimated load based on the recognized one or more regimes; and

determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component based on the first probability of failure and the identified at least one estimated load.

6. The method of claim 5, wherein the activity of the rotorcraft comprises an activity occurring while the rotorcraft is on the ground or while the rotorcraft is in the air.

7. The method of claim 5, wherein recognizing one or more regimes representative of the activity of the rotorcraft comprises:

identifying a plurality of regimes, each of the plurality of regimes having a different regime definition;

eliminating at least one of the plurality of regimes based on a conflict between the received one or more measurements and the regime definitions corresponding to the eliminated regimes; and

recognizing one or more regimes that were not eliminated.

8. The method of claim 1, wherein:

identifying, aboard the rotorcraft, the first probability of failure of the rotorcraft component installed on the rotorcraft further comprises;

identifying a first remaining useful life of the rotorcraft component, the first remaining useful life representing a remaining useful life of the rotorcraft component prior to application of the at least one load; and

determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component further comprises determining, based on the first remaining useful life and the received one or more measurements representative of the at least one load applied against the rotorcraft component, a second remaining useful life of the rotorcraft component, the second remaining useful life representing a remaining useful life of the rotorcraft component after application of the at least one load.

9. The method of claim 8, further comprising displaying, in the rotorcraft, the determined second remaining useful life of the rotorcraft component.

10. The method of claim 1, wherein the one or more measurements representative of the at least one load applied against the rotorcraft component are selected from the group consisting of:

environmental data, discrete-event data, state data, and direct and indirect load measurements.

11. A system for assessing reliability of a rotorcraft component, comprising:

a rotorcraft comprising a body, a power train coupled to the body and comprising a power source and a drive shaft coupled to the power source, a hub, a rotor blade coupled to the hub, and one or more sensors operable to provide a plurality of measurements; and

a prognostics health system, including at least one processor, installed onboard the rotorcraft and operable to;

identify, aboard the rotorcraft, a first probability of failure of the rotorcraft component installed on the rotorcraft, the first probability of failure representing a probability of failure of the rotorcraft component prior to application of at least one load;

receive, from the one or more sensors installed on the rotorcraft, one or more measurements representative of the at least one load applied against the rotorcraft component;

determine, aboard the rotorcraft, a second probability of failure of the rotorcraft component based on the first probability of failure and the received one or more measurements representative of the at least one load applied against the rotorcraft component, the second probability of failure representing a probability of failure of the rotorcraft component after application of the at least one load;

determine an equivalent life by assessing a cumulative damage of a change of a probability of failure and then converting the change of the probability of failure back into a time domain;

subtract a calculated used-life damage index from a baseline model to identify a variance and then credit the variance towards a remaining useful life of the aircraft component so as to extend the remaining useful life of the aircraft component; and

adjust at least one of an operation and a maintenance of the aircraft based on the remaining useful life.

12. The system of claim 11, wherein determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component comprises determining the second probability of failure during operation of the rotorcraft.

13. The system of claim 11, wherein the received one or more measurements further comprises an amount of time during which the at least one load was applied.

14. The system of claim 11, wherein the received one or more measurements further comprises a number of cycles for which the at least one load was applied.

15. The system of claim 11, wherein determining the second probability of failure of the rotorcraft component based on the first probability of failure and the received one or more measurements representative of the at least one load applied against the rotorcraft component comprises:

recognizing, using the received one or more measurements representative of the at least one load applied against the rotorcraft component, one or more regimes representative of an activity of the rotorcraft;

identifying at least one estimated load based on the recognized one or more regimes; and

determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component based on the first probability of failure and the identified at least one estimated load.

16. The system of claim 15, wherein the activity of the rotorcraft comprises an activity occurring while the rotorcraft is on the ground or while the rotorcraft is in the air.

17. The system of claim 15, wherein recognizing the one or more regimes representative of the activity of the rotorcraft comprises:

identifying a plurality of regimes, each of the plurality of regimes having a different regime definition;

eliminating at least one of the plurality of regimes based on a conflict between the received one or more measurements and the regime definitions corresponding to the eliminated regimes; and

recognizing one or more regimes that were not eliminated.

18. The system of claim 11, wherein identifying, aboard the rotorcraft, the first probability of failure of the rotorcraft component installed on the rotorcraft further comprises:

identifying a first remaining useful life of the rotorcraft component, the first remaining useful life representing a remaining useful life of the rotorcraft component prior to application of the at least one load; and

determining, aboard the rotorcraft, the second probability of failure of the rotorcraft component further comprises determining, based on the first remaining useful life and the received one or more measurements representative of the at least one load applied against the rotorcraft component, a second remaining useful life of the rotorcraft component, the second remaining useful life representing a remaining useful life of the rotorcraft component after application of the at least one load.

19. The system of claim 18, further comprising displaying, in the rotorcraft, the determined second remaining useful life of the rotorcraft component.

20. The system of claim 11, wherein the one or more measurements representative of the at least one load applied against the rotorcraft component are selected from the group consisting of:

environmental data, discrete-event data, state data, and direct and indirect load measurements.