Systems and methods for assembling a collection of peaks characterizing a gas leak source and selecting representative peaks for display

    公开(公告)号:US09823231B1

    公开(公告)日:2017-11-21

    申请号:US14319236

    申请日:2014-06-30

    申请人: Picarro Inc.

    摘要: In some embodiments, vehicle-based natural gas leak detection methods include assembling a collection of measured concentration peaks originating from a common natural gas leak according to wind direction, wind variability and inter-peak distance data, and selecting from the collection a subset of one or more representative peaks for display. Assigning peaks to a collection may be performed according to a peak overlap condition dependent upon a scaling (overlap) factor which scales the spatial reach of a peak, and according to a wind condition which determines whether a downwind event points toward an upwind event. The scaling factor may depend on wind variability and on an orientation of an inter-peak vector relative to a representative wind direction. Peak filtering is particularly useful in urban environments, where buildings channel gas plumes and one leak may lead to sequential detections of multiple concentration peaks along a path.

    Systems and methods for likelihood-based detection of gas leaks using mobile survey equipment

    公开(公告)号:US09599597B1

    公开(公告)日:2017-03-21

    申请号:US14139348

    申请日:2013-12-23

    申请人: Picarro Inc.

    IPC分类号: G01N31/00 G01N33/00

    摘要: In some embodiments, vehicle-based natural gas leak detection methods are used to generate 2-D spatial distributions (heat maps) of gas emission source probabilities and surveyed area locations using measured gas concentrations and associated geospatial (e.g. GPS) locations, wind direction and wind speed, and atmospheric condition data. Bayesian updates are used to incorporate the results of one or more measurement runs into computed spatial distributions. Operating in gas-emission plume space rather than raw concentration data space allows reducing the computational complexity of updating gas emission source probability heat maps. Gas pipeline location data and other external data may be used to determine the heat map data.

    Leak detection event aggregation and ranking systems and methods

    公开(公告)号:US11933774B1

    公开(公告)日:2024-03-19

    申请号:US18060111

    申请日:2022-11-30

    申请人: Picarro Inc.

    IPC分类号: G01N33/00 G01M3/04

    摘要: In some embodiments, data from multiple vehicle-based natural gas leak detection survey runs are used by computer-implemented machine learning systems to generate a list of natural gas leaks ranked by hazard level. A risk model embodies training data having known hazard levels, and is used to classify newly-discovered leaks. Hazard levels may be expressed by continuous variables, and/or probabilities that a given leak fits within a predefined category of hazard (e.g. Grades 1-3). Each leak is represented by a cluster of leak indications (peaks) originating from a common leak source. Hazard-predictive features may include maximum, minimum, mean, and/or median CH4/amplitude of aggregated leak indications; estimated leak flow rate, determined from an average of leak indications in a cluster; likelihood of leak being natural gas based on other indicator data (e.g. ethane concentration); probability the leak was detected on a given pass; and estimated distance to leak source.

    Systems and methods for likelihood-based detection of gas leaks using mobile survey equipment

    公开(公告)号:US10444108B1

    公开(公告)日:2019-10-15

    申请号:US16350419

    申请日:2018-11-12

    申请人: Picarro Inc.

    摘要: In some embodiments, vehicle-based natural gas leak detection methods are used to generate 2-D spatial distributions (heat maps) of gas emission source probabilities and surveyed area locations using measured gas concentrations and associated geospatial (e.g. GPS) locations, wind direction and wind speed, and atmospheric condition data. Bayesian updates are used to incorporate the results of one or more measurement runs into computed spatial distributions. Operating in gas-emission plume space rather than raw concentration data space allows reducing the computational complexity of updating gas emission source probability heat maps. Gas pipeline location data and other external data may be used to determine the heat map data.

    Leak detection event aggregation and ranking systems and methods

    公开(公告)号:US11525819B1

    公开(公告)日:2022-12-13

    申请号:US17249795

    申请日:2021-03-12

    申请人: Picarro Inc.

    IPC分类号: G01N33/00 G01M3/04

    摘要: In some embodiments, data from multiple vehicle-based natural gas leak detection survey runs are used by computer-implemented machine learning systems to generate a list of natural gas leaks ranked by hazard level. A risk model embodies training data having known hazard levels, and is used to classify newly-discovered leaks. Hazard levels may be expressed by continuous variables, and/or probabilities that a given leak fits within a predefined category of hazard (e.g. Grades 1-3). Each leak is represented by a cluster of leak indications (peaks) originating from a common leak sources. Hazard-predictive features may include maximum, minimum, mean, and/or median CH4/amplitude of aggregated leak indications; estimated leak flow rate, determined from an average of leak indications in a cluster; likelihood of leak being natural gas based on other indicator data (e.g. ethane concentration); probability the leak was detected on a given pass; and estimated distance to leak source.

    Gas detection systems and methods using search area indicators

    公开(公告)号:US10775262B1

    公开(公告)日:2020-09-15

    申请号:US16450970

    申请日:2019-06-24

    申请人: Picarro Inc.

    摘要: In some embodiments, a computer system generates display content indicating a likely direction and estimated distance to a potential gas leak source. The content includes a street map and at least one search area indicator on the map that indicates a search area suspected to have a gas leak source. The search area indicator has an axis indicating a representative wind direction relative to a geo-referenced location of at least one gas concentration measurement point. The search area indicator also has a width relative to the axis. The width is indicative of a wind direction variability associated with a plurality of wind direction measurements in an area of the gas concentration measurement point. The axis also preferably has a length indicating an estimated maximum distance to the potential gas leak source.

    Systems and methods for detecting changes in emission rates of gas leaks in ensembles

    公开(公告)号:US10386258B1

    公开(公告)日:2019-08-20

    申请号:US15144751

    申请日:2016-05-02

    申请人: Picarro Inc.

    IPC分类号: G01M3/00 G01M3/04

    摘要: In some embodiments, computer-implemented systems/methods detect and/or quantify changes in emission rates of gas emission sources (e.g. natural gas leaks originating from underground distribution pipelines) using data from multiple vehicle-based measurement runs. Exemplary described methods aim to address the observation that large (e.g. 10×) changes in gas concentrations away from a source may be observed even in the absence of significant changes in source emission rate, due to changes in wind or other atmospheric conditions and local spatial variations in gas concentrations. Described methods are useful for identifying large increases in the emission rate(s) of known sources, for example due to frost heave or other dislocations. Multiple runs are performed along the same survey path in closely-related conditions (e.g. same time of day, same lanes), and a statistical test (e.g. a Kolmogorov-Smirnov test) is used to identify changes in concentration reflecting changes in emission rates.

    Gas detection systems and methods using measurement position uncertainty representations

    公开(公告)号:US10962438B2

    公开(公告)日:2021-03-30

    申请号:US16826265

    申请日:2020-03-22

    申请人: Picarro Inc.

    摘要: In some embodiments, a natural gas leak detection system generates display content including indicators of remote and local potential leak source areas situated on a map of an area of a gas concentration measurement survey performed by a vehicle-borne device. The remote area may be shaped as a wedge extending upwind from an associated gas concentration measurement point. The local area graphically represents a potential local leak source area situated around the gas concentration measurement point, and having a boundary within a predetermined distance (e.g. 10 meters) of the gas concentration measurement point. The local area may be represented as a circle, ellipse, or other shape, and may include an area downwind from the measurement point. Size and/or shape parameters of the local area indicator may be determined according to survey vehicle speed and direction data, and/or wind speed and direction data characterizing the measurement point.

    Aggregate leak indicator display systems and methods

    公开(公告)号:US10962437B1

    公开(公告)日:2021-03-30

    申请号:US16020874

    申请日:2018-06-27

    申请人: Picarro Inc.

    摘要: In some embodiments, data from a vehicle-borne gas leak detection survey are used to generate an aggregate leak indication search area (LISA) indicator for a plurality of leak indications (measurement peaks) characterizing a single leak or localized set of leaks. A clustering algorithm (e.g. Markov, DBScan) may be used to group a set of indications into a cluster characterizing the leak. Leak indications may be pre-filtered for quality control before assignment to a cluster according to a number of parameters including background gas level, inter-peak distance, peak shape, wind speed, wind direction and/or variability, vehicle speed and/or acceleration, and/or a lower detection threshold for leak flow rate.

    Gas Detection systems and methods using search area indicators

    公开(公告)号:US10337946B1

    公开(公告)日:2019-07-02

    申请号:US15418367

    申请日:2017-01-27

    申请人: Picarro Inc.

    摘要: In some embodiments, a computer system generates display content indicating a likely direction and estimated distance to a potential gas leak source. The content includes a street map and at least one search area indicator on the map that indicates a search area suspected to have a gas leak source. The search area indicator has an axis indicating a representative wind direction relative to a geo-referenced location of at least one gas concentration measurement point. The search area indicator also has a width relative to the axis. The width is indicative of a wind direction variability associated with a plurality of wind direction measurements in an area of the gas concentration measurement point. The axis also preferably has a length indicating an estimated maximum distance to the potential gas leak source.