# US 11,307,137 B2 · Systems and methods for locating sources of fugitive gas emissions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,307,137 B2 - Document ID: US11307137B2 - Status: Granted - Kind: B2 - Application number: 16/692,247 - Filed: 2019-11-22 - Published: 2021-05-27 - Granted: 2022-04-19 - Earliest claimed: 2019-11-22 - Assignees: ABB Schweiz AG - Applicants: ABB Schweiz AG - Inventors: J. Brian Leen; Yi-wen Huang - Web page: https://patentgrep.com/patent/US11307137B2 ## CPC - G01M 3/20: using special tracer materials, e.g. dye, fluorescent material, radioactive material - G01N 21/31: Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} - G01C 19/00: Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects - G01M 3/04: by detecting the presence of fluid at the leakage point - G01M 3/16: using electric detection means ({G01M3/045,} G01M3/06, G01M3/12, G01M3/20, G01M3/24, G01M3/26 take precedence) - G01N 33/0047: {Organic compounds} - G01P 15/18: in two or more dimensions - G01S 19/01: Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO - G01N 2201/12: Circuits of general importance; Signal processing - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - 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}) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract A fugitive gas detection system includes an inertial measurement assembly that measures a change in position of the inlet of a gas analyzer and applies a time slip to concentration data detected by an analyzer to generate a time series of the concentration of the gas in three-dimensional space. Applying statistical methods, the relative location of the source of the fugitive gas can be established from the time series. Additionally, in some embodiments, the data may be interpolated to establish a map of a plume of the fugitive gas. ## Claims ### Claim 1 A gas leak detector comprising: an inertial measurement assembly; a high precision gas analyzer; a wand having an inlet that receives ambient air and directs all or part of the ambient air to the high precision gas analyzer, the wand physically coupled to the inertial measurement assembly such that movement of the wand is detected by the inertial measurement assembly; and a controller receiving signals from the inertial measurement assembly and the high precision gas analyzer, the controller including processor and a memory device, the memory device including instructions that, when acted upon by the processor, cause the controller to: monitor the signals from the inertial measurement assembly to identify real-time changes in location of the inlet of the wand; log the changes in location; monitor signals from the high precision gas analyzer indicative of a concentration of a one or more particular type of fugitive gas dispersed in the ambient air; log the concentration of particular molecules of each of the one or more particular type of fugitive gas dispersed in the ambient air; apply an adjustment factor based on characteristics of the wand to a time series of the concentration of the particular type of fugitive gas in the ambient air to offset the time series such that the measured concentration of the particular type of fugitive gas is aligned with the location of the inlet of the wand when the measured concentration entered the wand to create an adjusted concentration time series; and log the adjusted concentration time series with the changes in location time series to create a combined time series that includes both position and fugitive gas concentration data. ### Claim 2 (depends on 1) The gas leak detector of claim 1, wherein the inertial measurement assembly measures three-dimensional changes in position of the inertial measurement assembly and measure changes in a pitch, a roll, and a yaw of the inertial measurement assembly to provide the signals to the controller indicative of changes in the location of the inlet of the wand. ### Claim 3 (depends on 1) The gas leak detector of claim 1, wherein the inertial measurement assembly includes a structure capable of measuring acceleration in three orthogonal axes. ### Claim 4 (depends on 1) The gas leak detector of claim 1, wherein the inertial measurement assembly includes a structure capable of measuring gyroscopic deviations about three orthogonal axes. ### Claim 5 (depends on 1) The gas leak detector of claim 1, wherein the high precision gas analyzer utilizes integrated cavity output spectroscopy to measure the concentration of a particular type of gas in the ambient air. ### Claim 6 (depends on 5) The gas leak detector of claim 5, wherein the memory device includes further instructions that, when acted upon by the processor, cause the processor to utilize a Gaussian plume model to evaluate the combined time series that includes both position and concentration data to determine a vector indicative of a likely location of a source of the fugitive gas. ### Claim 7 (depends on 5) The gas leak detector of claim 5 wherein the memory device includes further instructions that, when acted upon by the processor, cause the processor to utilize a Bayesian estimation to evaluate the combined time series that includes both position and concentration data to determine a vector indicative of a likely location of a source of the fugitive gas. ### Claim 8 (depends on 5) The gas leak detector of claim 5 wherein the memory device includes further instructions that, when executed by the processor, cause the processor to utilize a plurality of winds around a peak of spatial or temporal methane peaks in the combined time series that includes both position and concentration data to determine a vector indicative of a likely location of a source of the fugitive gas. ### Claim 9 (depends on 1) The gas leak detector of claim 1, wherein the gas leak detector further comprises a user interface in communication with the controller, the memory device including instructions that, when executed by the processor, provide an output to the user interface that causes the user interface to provide a real-time indication of a likely direction and/or location of a source of the fugitive gas relative to the gas leak detector. ### Claim 10 (depends on 1) The gas leak detector of claim 1, wherein the controller receives a signal from a geospatial position satellite system indicative of a geospatial reference datum while a positional data series is being collected, and wherein the memory device includes instructions that, when executed by the processor, cause the processor to process the real-time changes in position of the inertial measurement assembly to create an adjusted time series of position data to reference a geospatial location of the inlet of the wand, and create a combined time series that includes both geospatial position and fugitive gas concentration data. ### Claim 11 (depends on 10) The gas leak detector of claim 10, wherein the gas leak detector further comprises a user interface in communication with the controller, the memory device including instructions that, when executed by the processor, provide an output to the user interface that causes the user interface to provide a real-time indication of a likely location of a source of the fugitive gas relative to the gas leak detector. ### Claim 12 A method of identifying a source location of a gas leak, the method comprising: moving an inlet of a handheld gas analyzer in space to collect ambient air samples; measuring real-time changes in a position of the inlet of the handheld gas analyzer using an inertial measurement assembly; logging a time series of the changes in position of the inlet; measuring a real-time concentration of a particular fugitive gas using a high precision gas analyzer; adjusting the real-time concentration of the particular fugitive gas with a time slip factor to account for delays in a transfer of the fugitive gas from the inlet to the high precision gas analyzer to generate a time-slipped data series of the concentration; and combining the time-slipped data series of the concentration with a time series of changes in position of the inlet to create a time series indicative of a relative position of the inlet and the concentration of fugitive gas at the inlet over time. ### Claim 13 (depends on 12) The method of claim 12, further comprising: determining a reference geospatial position of the inertial measurement assembly during the real-time changes in position; offsetting the time series of the relative position of the inlet with the reference geospatial position to create a time series of the geospatial position of the inlet; and combining the time-slipped concentration data series with the time series of the geospatial position of the inlet to create a time series indicative of the geospatial position of the inlet and the concentration of fugitive gas at the inlet over time. ### Claim 14 (depends on 13) The method of claim 13, further comprising: utilizing a Gaussian plume model to evaluate the combined time series that includes both position and concentration data to determine a vector indicative of a likely location of a source of the fugitive gas; and outputting a visual representation of the likely location of the source of the fugitive gas on a display device. ### Claim 15 (depends on 13) The method of claim 13, further comprising: utilizing a Bayesian estimation to evaluate the combined time series that includes both position and concentration data to determine a vector indicative of a likely location of a source of the fugitive gas; and outputting a visual representation of the likely location of the source of the fugitive gas on a display device. ### Claim 16 (depends on 13) The method of claim 13, further comprising: processing the time series indicative of the geospatial position of the inlet and the concentration of fugitive gas at the inlet over time with a statistical interpolation to create a three-dimensional data set that approximates the concentration of the fugitive gas in space; and plotting the three-dimensional data set that approximates the concentration of the fugitive gas in space to create a visual representation of the concentration on a map. ### Claim 17 A system for measuring a distribution of a fugitive gas in three dimensions, the system comprising: an inertial measurement assembly providing a signal indicative of changes in three-dimensional position and three-axis orientation of the inertial measurement assembly in real-time; a high precision gas analyzer to measure a concentration of a gas in real-time; a wand having an inlet with a tip that receives ambient air and directs the ambient air to the high precision gas analyzer, the wand physically coupled to the inertial measurement assembly such that movement of the wand is detected by the inertial measurement assembly; a user interface having user input devices and a display; and a controller in communication with the inertial measurement assembly, the high precision gas analyzer, and the user interface, the controller including a processor and a memory device coupled to the processor, wherein the memory device stores instructions that, when executed by the processor: cause the user interface to display a prompt a user to input data regarding a configuration of the wand; receive a signal from the user input devices indicative of the configuration of the wand; based on the configuration of the wand, establish a time slip parameter for monitoring ambient air for the concentration of the gas and establish an offset from the tip of the inlet to the inertial measurement assembly; and log a time series that includes a change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space. ### Claim 18 (depends on 17) The system of claim 17, wherein the memory device includes instructions that, when executed by the processor, apply a statistical interpolation to the time series log to create a three-dimensional data set that approximates the concentration of the fugitive gas in space. ### Claim 19 (depends on 17) The system of claim 17, wherein the memory device includes instructions that, when executed by the processor, apply a Gaussian plume model to evaluate the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to determine a vector indicative of a likely location of a source of the fugitive gas. ### Claim 20 (depends on 17) The system of claim 17, wherein the memory device includes instructions that, when executed by the processor, apply a Bayesian estimation to evaluate the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to determine a vector indicative of a likely location of a source of the fugitive gas. ### Claim 21 (depends on 17) The system of claim 17, wherein the memory device includes instructions that, when executed by the processor, cause the processor to signal the user interface to prompt a user to input a geospatial reference location and adjust the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to convert the changes in location to geospatial location data. ### Claim 22 (depends on 21) The system of claim 21, wherein the memory device includes instructions that, when executed by the processor, apply a Gaussian plume model to evaluate the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to determine a geospatial location of a source of the fugitive gas. ### Claim 23 (depends on 21) The system of claim 21, wherein the system further comprises a sonic or mechanical anemometer in communication with the controller, the memory device including instructions that, when executed by the processor, cause the processor to update the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to include wind vector information, and, wherein a Gaussian plume model is applied using a wind vector to determine a geospatial location of a source of the fugitive gas. ### Claim 24 (depends on 17) The system of claim 17, wherein the system further comprises an anemometer in communication with the controller, the memory device including instructions that, when executed by the processor, cause the processor to update the time series that includes the change in position of the tip of the inlet and the time slipped concentration data as the tip of the inlet is moved in space to include wind vector information, apply a statistical interpolation to the time series log to create a three-dimensional data set that approximates the concentration of the fugitive gas in space, and generate a visual representation of the distribution of the concentration of the fugitive gas in space on the display of the user interface.