# US 2014/0156226 A1 · Pitot Tube Diagnostic Systems and Methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0156226 A1 - Document ID: US20140156226A1 - Status: Published application - Kind: A1 - Application number: 13/899,045 - Filed: 2013-05-21 - Published: 2014-06-05 - Earliest claimed: 2010-01-28 - Assignees: Analysis and Measurement Services Corporation - Applicants: Analysis and Measurement Services Corporation - Inventors: Hashem M. Hashemian; Ryan Douglas O'Hagan - Web page: https://patentgrep.com/patent/US20140156226A1 ## CPC - G06F 17/18: for evaluating statistical data {, e.g. average values, frequency distributions, probability functions, regression analysis (forecasting specially adapted for a specific administrative, business or logistic context G06Q10/04)} - G01F 1/46: Pitot tubes - G01F 25/10: of flowmeters - G01P 5/16: using Pitot tubes {, e.g. Machmeter} - G01P 21/025: {for measuring speed of fluids; for measuring speed of bodies relative to fluids (for measuring volume flow G01F25/10)} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) ## Abstract A pitot tube diagnostic system including a data acquisition unit to acquire an output signal of a pitot-static system, the output signal having a static component and a dynamic component, and a processing unit to monitor the dynamic component for one or more characteristics that deviate from one or more predetermined reference characteristics to indicate impairment of the pitot-static system. ## Claims ### Claim 1 A pitot tube diagnostic system, comprising: a data acquisition unit to acquire an electrical output signal of a pitot-static system (PSS), the output signal having a static component and a dynamic component; and a processing unit to monitor the dynamic component for one or more characteristics that deviate from one or more predetermined reference characteristics to indicate impairment of the PSS. ### Claim 2 (depends on 1) The pitot tube diagnostic system of claim 1, further comprising a signal conditioning unit to filter the output signal, wherein the data acquisition unit samples filtered output signals to enable the processing unit to analyze the dynamic component for anomalies that indicate the PSS is at least partially blocked. ### Claim 3 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the processing system monitors the dynamic component over time by calculating a power spectral density curve for the dynamic component and monitoring the power spectral density curve against a baseline curve to identify a change in the dynamic component over time. ### Claim 4 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the processing system calculates an amplitude probability density plot for the dynamic component and monitors the amplitude probability density plot against a Gaussian distribution curve to measure a degree of abnormality of the dynamic component. ### Claim 5 (depends on 2) The pitot tube diagnostic system of claim 2, wherein the processing system monitors for blockages by calculation of skewness, kurtosis, and higher moments of the dynamic component. ### Claim 6 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the processing system monitors the dynamic component by Auto Regressive (AR) modeling allowing the pitot tube diagnostic system to perform diagnostics autonomously without user interpretation. ### Claim 7 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the dynamic component is monitored using zero-cross calculations performed by the processing system to monitor the number of times the dynamic component crosses an average value per unit of time. ### Claim 8 (depends on 2) The pitot tube diagnostic system of claim 2, wherein the signal conditioner applies a high-pass filter to the output signals to isolate the dynamic component from the static component. ### Claim 9 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the processing system qualifies the sampled output signals by screening the sampled output signals for linearity, normality, and the presence of erroneous data records by identifying and examining a mean value of a predetermined number of blocks of the output signals of the pitot-static system against a baseline value to identify outliers. ### Claim 10 (depends on 1) The pitot tube diagnostic system of claim 1, wherein the processing system qualifies the 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 a degree of abnormality of the dynamic component. ### Claim 11 A method of diagnosing health of a pitot-static system, comprising: directing an air input to a pitot-static system (PSS); acquiring an electrical output signal of the PSS which is a function of the air input, the output signal including a static component and a dynamic component; and monitoring the dynamic component for one or more characteristics that deviate from one or more predetermined reference characteristics to indicate impairment of the PSS. ### Claim 12 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component includes determining whether the pitot-static system is impaired, degraded, or blocked. ### Claim 13 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component includes: calculating a power spectral density curve for the dynamic component; and evaluating the power spectral density curve for deviations from a baseline curve baseline curve to identify a change in the dynamic component over time. ### Claim 14 (depends on 13) The method of claim 13, further including the operation of: performing a fast Fourier transform on the dynamic component to produce the power spectral density curve representing response time for the dynamic component. ### Claim 15 (depends on 13) The method of claim 13, wherein the operation of monitoring the dynamic component further includes monitoring the power spectral density curve for deviations from a baseline comparison that is indicative of blockage. ### Claim 16 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component further includes: calculating an amplitude probability density plot for the dynamic component; and evaluating the amplitude probability density plot against a Gaussian distribution curve to measure the degree of abnormality of the dynamic component. ### Claim 17 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component further includes: calculating of skewness, kurtosis, and higher moments of the dynamic component. ### Claim 18 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component further includes: monitoring the dynamic component by Auto Regressive (AR) modeling. ### Claim 19 (depends on 11) The method of claim 11, wherein the operation of monitoring the dynamic component further includes: using zero-cross calculations to monitor the number of times the dynamic component crosses an average value per unit of time. ### Claim 20 A pitot tube diagnostic system installed to a pitot-static system of an aircraft comprising: a data acquisition unit to acquire an output signal of a pitot-static system (PSS) during flight of the aircraft, the output signal having a static component and a dynamic component; and a processing unit to monitor the dynamic component for one or more characteristics that deviate from one or more predetermined reference characteristics to indicate impairment of the PSS.