Pitot Tube Diagnostic System

• US 20110184701A1
• Filed: 01/28/2011
• Published: 07/28/2011
• Est. Priority Date: 01/28/2010
• Status: Abandoned Application

• Current Assignee: Analysis And Measurement Services Corporation
• Original Assignee: Analysis And Measurement Services Corporation
• Inventors: Hashemian, Hashem M., ORME, Bradley Louis, O'Hagan, Ryan Douglas
• Application Number:
  US13/015,783
• Publication Number:
  US 20110184701A1
• Time in Patent Office: Days
• US Class Current: 702/183
• CPC Class Codes: G01F 1/46 Pitot tubes
• CPC Class Codes: G01F 25/10 of flowmeters
• CPC Class Codes: G01P 21/025 for measuring speed of fluids; for measuring speed of bodies relative to fluids for measuring volume flow G01F25/10
• CPC Class Codes: G01P 5/16 using Pitot tubes , e.g. Machmeter

Abstract

A pitot tube diagnostic system and method for determining the health of a pitot tube is disclosed. The pitot tube diagnostic system is configured to be temporarily connectable to or permanently installable in an airplane'"'"'s pitot-static system, which allows the pitot tube diagnostic system to be utilized during pre-flight inspections and/or in-flight conditions. The pitot tube diagnostic system is in electrical communication with the pitot-static system for acquisition of output signals and analysis thereof. Thus, the pitot-static diagnostic system is able to diagnose anomalies in the pitot-static systems that are representative of the overall health and efficiency of the pitot-static system.

Claims

1. A pitot tube diagnostic system comprising:

a data acquisition unit to sample output signals of a pitot-static system; and

a processing unit to filter said sampled output signals to isolate a dynamic component of said sampled output signal and to monitor said dynamic component over time to diagnose the health of the pitot-static system.

2. The pitot tube diagnostic system of claim 1 wherein said processing unit diagnoses the health of said pitot-static system by analyzing said output signals of said pitot-static system for anomalies that indicate said pitot-static system is impaired, degraded, or blocked.

3. The pitot tube diagnostic system of claim 1 wherein said processing unit monitors said dynamic component over time by calculating a power spectral density curve for said dynamic component and monitoring said power spectral density curve against a baseline curve for the dynamic component.

4. The pitot tube diagnostic system of claim 1 wherein said processing unit calculates an amplitude probability density plot for said dynamic component and evaluates said amplitude probability density plot against a Gaussian distribution curve to measure the degree of abnormality of said dynamic component.

5. The pitot tube diagnostic system of claim 1 wherein said processing unit evaluates for blockages by calculation of skewness, kurtosis, and higher movements of said dynamic component.

6. The pitot tube diagnostic system of claim 1 wherein said processing unit evaluates the dynamic component by Auto Regressive (AR) modeling allowing said pitot tube diagnostic system to perform diagnostics autonomously without user interpretation.

7. The pitot tube diagnostic system of claim 1 wherein said dynamic component is evaluated using zero-cross calculations performed by said processing unit to monitor the number of times that the dynamic component crosses an average value per unit of time.

8. The pitot tube diagnostic system of claim 1 wherein said processing unit applies a low-pass filter to said sampled output signals to obtain said dynamic component in said sampled output signals.

9. The pitot tube diagnostic system of claim 1 wherein said processing unit qualifies the sampled output signals by screening said sampled output signals for linearity, normality, and the presence of erroneous data records by identifying and examining a mean value of said output signals of said pitot-static system against a baseline value.

10. The pitot tube diagnostic system of claim 1 wherein said processing unit qualifies said sampled output signals by screening the sampled output signals for linearity, normality, and the presence of erroneous data records by generating an amplitude probability density plot and calculating and examining the data qualification parameters including variance, skewness, and kurtosis to determine the degree of abnormality of said dynamic component.

11. A method for diagnosing the health of a pitot-static system during pre-flight inspections, comprising:

generating a random pressure signal;

directing said random pressure signal to the pitot-static system;

sampling output signals of said pitot-static system generated by said pitot-static system in response to said random pressure signal;

filtering said sampled output signals to isolate a dynamic component of said sampled output signals; and

monitoring said dynamic component to diagnose the health of said pitot-static system in pre-flight inspections.

12. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring said dynamic component to diagnose the health of said pitot-static system includes determining whether said pitot-static system is impaired, degraded, or blocked.

13. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system in pre-flight inspections includes:

calculating a power spectral density curve for the dynamic component; and

evaluating the power spectral density curve for deviations from a baseline curve for the dynamic component.

14. The method for diagnosing the health of a pitot-static system of claim 13 further including the operation of:

performing the fast Fourier transform on the dynamic component to produce said power spectral density curve representing response time for the dynamic component.

15. The method for diagnosing the health of a pitot-static system of claim 13 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system further includes monitoring the power spectral density curve for deviations from a baseline comparison that is indicative of blockage.

16. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system further includes:

calculating an amplitude probability density plot for said dynamic component; and

evaluating said amplitude probability density plot against a Gaussian distribution curve to measure the degree of abnormality of said dynamic component.

17. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system further includes:

calculating of skewness, kurtosis, and higher movements of said dynamic component.

18. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system further includes:

monitoring said dynamic component by Auto Regressive (AR) modeling.

19. The method for diagnosing the health of a pitot-static system of claim 11 wherein the operation of monitoring the dynamic component to diagnose the health of said pitot-static system further includes:

using zero-cross calculations to monitor the number of times that the dynamic component crosses an average value per unit of time.

20. A pitot tube diagnostic system installed to a pitot-static system of an aircraft comprising:

a data acquisition unit to sample sensor output signals of said pitot-static system during flight of the aircraft; and

a processing unit to filter said sampled output signals to isolate a dynamic component of said sampled output signal and to monitor said dynamic component over time to diagnose the health of said pitot-static system.

21. The pitot tube diagnostic system of claim 20 wherein said processing unit diagnoses the health of said pitot-static system by analyzing said output signals of said pitot-static system for anomalies that indicate said pitot-static system is impaired, degraded, or blocked.

22. The pitot tube diagnostic system of claim 20 wherein said processing unit monitors said dynamic component over time by calculating a power spectral density curve for said dynamic component and monitoring said power spectral density curve against a baseline curve for the dynamic component.

23. The pitot tube diagnostic system of claim 20 wherein said processing unit calculates an amplitude probability density plot for said dynamic component and evaluates said amplitude probability density plot against a Gaussian distribution curve to measure the degree of abnormality of said dynamic component.

24. The pitot tube diagnostic system of claim 20 wherein said processing unit evaluates for blockages by calculation of skewness, kurtosis, and higher movements of said dynamic component.

25. The pitot tube diagnostic system of claim 20 wherein said processing unit evaluates the dynamic component by Auto Regressive (AR) modeling allowing said pitot tube diagnostic system to perform diagnostics autonomously without user interpretation.

26. The pitot tube diagnostic system of claim 20 wherein said dynamic component is evaluated using a zero-cross calculation performed by said processing unit to monitor the number of times that the dynamic component crosses an average value per unit of time.

27. The pitot tube diagnostic system of claim 20 wherein said processing unit applies a low-pass filter to said sampled output signals to obtain said dynamic component in said sampled output signals.

28. The pitot tube diagnostic system of claim 20 wherein said processing unit qualifies the sampled output signals by screening said sampled output signals for linearity, normality, and the presence of erroneous data records by identifying and examining a mean value of said output signals of said pitot-static system against a baseline value.

29. The pitot tube diagnostic system of claim 20 wherein said processing unit qualifies said sampled output signals by screening the sampled output signals for linearity, normality, and the presence of erroneous data records by generating an amplitude probability density plot and calculating and examining the data qualification parameters including variance, skewness, and kurtosis to determine the degree of abnormality of said dynamic component.