SYSTEM AND METHOD OF ROTORCRAFT USAGE MONITORING

• US 20150007666A1
• Filed: 07/02/2014
• Published: 01/08/2015
• Est. Priority Date: 07/02/2013
• Status: Active Grant

• Current Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Original Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Inventors: Wardlaw, Robert, Tucker, Brian, Wood, Tom, Nguyen, Bang, Altman, Allen
• Granted Patent: US 10,496,787 B2
• Time in Patent Office: Days
• US Class Current: 73/787
• CPC Class Codes: B64F 5/60 Testing or inspecting aircraft components or systems
• CPC Class Codes: G01L 5/00 Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
• CPC Class Codes: G05B 19/4065 Monitoring tool breakage, life or condition
• CPC Class Codes: G05B 2219/34477 Fault prediction, analyzing signal trends
• CPC Class Codes: G05B 2219/37253 Fail estimation as function of lapsed time of use
• CPC Class Codes: G05B 23/024 Quantitative history assessment, e.g. mathematical relationships between available data; Functions therefor; Principal component analysis [PCA]; Partial least square [PLS]; Statistical classifiers, e.g. Bayesian networks, linear regression or correlation analysis; Neural networks
• CPC Class Codes: G05B 23/0254 based on a quantitative model, e.g. mathematical relationships between inputs and outputs; functions: observer, Kalman filter, residual calculation, Neural Networks
• CPC Class Codes: G05B 23/0281 Quantitative, e.g. mathematical distance; Clustering; Neural networks; Statistical analysis
• CPC Class Codes: G05B 23/0283 Predictive maintenance, e.g. involving the monitoring of a system and, based on the monitoring results, taking decisions on the maintenance schedule of the monitored system; Estimating remaining useful life [RUL] preventive maintenance, i.e. planning maintenance according to the available resources without monitoring the system G06Q10/06
• CPC Class Codes: G06F 30/15 Vehicle, aircraft or watercraft design
• CPC Class Codes: G07C 5/085 using electronic data carriers

Abstract

A method of monitoring usage of a component of an aircraft can include: monitoring a usage of the component by using a torque measurement system to calculate torque events in a time period; categorizing the usage of the component by assigning a usage value based upon whether the number of torque events in the period of time is above or below a threshold; and determining a life used of the component.

Claims

1. A method of monitoring usage of a component of an aircraft, the method comprising:

monitoring a usage of the component by using a torque measurement system to calculate torque events over a time period;

categorizing the usage of the component by assigning a usage value based upon whether a number of torque events in the time period is above or below a threshold; and

determining a life used of the component.

2. The method according to claim 1, wherein the torque events are obtained by measuring torque in a main rotor mast.

3. The method according to claim 1, wherein the torque events are obtained by measuring torque in a tail rotor drive shaft.

4. The method according to claim 1, wherein the step of monitoring the usage of the component by using a torque measurement system to calculate torque events in the time period includes utilizing a peak/valley filter to identify the torque events.

5. The method according to claim 1, wherein the step of monitoring the usage of the component by using a torque measurement system to calculate torque events in the time period includes utilizing a peak/valley filter to associate a peak point with each peak and associate a valley point with each valley.

6. The method according to claim 5, wherein the step of monitoring the usage of the component by using the torque measurement system to calculate torque events in the time period includes applying a rainflow cycle count to pair together the peak point with the valley point.

7. The method according to claim 1, wherein the step of monitoring the usage of the component by using the torque measurement system to calculate torque events in the time period includes binning the torque events such that a single peak point and a single valley point are paired together to form the torque event.

8. The method according to claim 1, wherein the step of monitoring the usage of the component by using the torque measurement system to calculate torque events in the time period includes applying a weighted value to each torque event, the weighted value being indicative of a severity of the torque event.

9. The method according to claim 1, wherein the step of monitoring the usage of the component by using the torque measurement system to calculate torque events in the time period includes summing the torque events.

10. The method according to claim 1, wherein the step of categorizing the usage of the component by assigning the usage value based upon whether the number of torque events in the period of time is above or below the threshold further includes assigning the usage to a short haul category if the number of torque events in the period of time is above the threshold.

11. The method according to claim 1, wherein the step of categorizing the usage of the component by assigning the usage value based upon whether the number of torque events in the time period is above or below the threshold further includes assigning the usage to a long haul category if the number of torque events in the period of time is below the threshold.

12. The method according to claim 1, wherein the step of determining the life used of the component includes adjusting a measured flight time by multiplying the measured flight time by a factor that is dependent upon the usage value.

13. The method according to claim 12, wherein the factor causes an increase in the life used of the component when the usage is more severe than a nominal usage.

14. The method according to claim 12, wherein the factor causes a decrease in the life used of the component when the usage is less severe than a nominal usage.

15. The method according to claim 1, wherein the aircraft is a rotorcraft.

16. The method according to claim 15, wherein the rotorcraft is a helicopter.

17. A system for monitoring a usage of a component of an aircraft, the system comprising:

a torque monitoring system configured to measure torque events over a time period;

a computer processor operable to categorize the usage of the component by assigning a usage value by calculating a ratio of the torque events to the time period and comparing the ratio to a threshold, the computer processor further operable to determine a life used of the component by adjusting a measured flight time by multiplying the measured flight time by a factor that is dependent upon the usage value.

18. The system according to claim 17, wherein the factor causes an increase in the life used of the component when a measured usage is more severe than a predetermined nominal usage, the measured usage being derived from the torque events over the time period.

19. The system according to claim 17, wherein the factor causes decrease in the life used of the component when a measured usage is less severe than a predetermined nominal usage, the measured usage being derived from the torque events over the time period.

20. A method of designing a component for an aircraft, the method comprising:

assigning a usage threshold to the component, the usage threshold being less than a most severe usage;

assigning a life factor to the component, the life factor being a ratio of a first calculated life to a second calculated life, wherein the first calculated life is a calculated life of the component corresponding with an amount of fatigue damage the component would incur at the usage threshold, and wherein the second calculated life is a calculated life of the component corresponding with an amount of fatigue damage the component would incur at the most severe usage; and

using a computer to design at least one dimension of the component based upon the usage threshold.