Gas leakage detector, gas leakage detection system, gas leakage detection method, and program

Abstract

SOLUTION: A gas leakage detector may include a movement control unit for controlling the movement of a mobile body to which a gas sensor is mounted. The gas leakage detector may include an acquisition unit for acquiring a target gas measurement result having been measured by the gas sensor while the mobile body is moving in a target area and a response time from when the gas sensor started measurement to when it outputs the measurement result. The gas leakage detector may include a detection unit for detecting the leakage of the target gas in the target area on the basis of the measurement result and the response time. The detection unit may detect leakage of the target gas in the target area and identify a gas leakage point on the basis of the measurement result and location information of the mobile body.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas leak detection device, a gas leak detection system, a gas leak detection method, and a program. [Background technology]

[0002] Patent Document 1 describes a gas leak detection method in which a gas analysis operation is performed when a mobile detection device becomes stationary to detect a gas leak. [Prior art document] [Patent documents] [Patent Document 1] U.S. Patent No. 10,520,387 Summary of the Invention [Problem to be solved by the invention]

[0003] When inspecting for gas leaks over a wide area using a mobile detection device as described above, if the mobile detection device is kept stationary for each gas leak inspection, it will take a long time to inspect the entire area to be detected. [Means for solving the problem]

[0004] A gas leak detection device according to one aspect of the present invention may include a movement control unit that controls the movement of a moving object equipped with a gas sensor. The gas leak detection device may include an acquisition unit that acquires measurement results of a target gas measured by the gas sensor while the moving object is moving in a target area and a response time from when the gas sensor starts measuring to when it outputs the measurement results. The gas leak detection device may include a detection unit that detects a leak of the target gas in the target area based on the measurement results and the response time and identifies a gas leak point.

[0005] In the gas leak detection device, the acquisition unit may further acquire location information of the moving object when the measurement result was acquired from the gas sensor, and the detection unit may identify a gas leak point where a leak of the target gas was detected within the target area based on the location information.

[0006] In the gas leak detection device, the acquisition unit may further acquire speed information of the moving object when the measurement result was acquired from the gas sensor. The detection unit may specify the gas leak location area based on the speed information.

[0007] In any of the gas leak detection devices, when there is a gas leak candidate area in which the gas concentration of the target gas based on the measurement result measured by the gas sensor while the moving body is moving at a first speed satisfies a first condition, the movement control unit may control the movement of the moving body so that the moving body moves through the gas leak candidate area at a second speed slower than the first speed, or stays in the gas leak candidate area. The acquisition unit may acquire additional measurement results of the target gas measured by the gas sensor while the moving body moves through the gas leak candidate area at the second speed or stays in the gas leak candidate area. The detection unit may identify the gas leak candidate area as the gas leak point when the gas concentration of the target gas based on the additional measurement result satisfies a second condition.

[0008] In any of the gas leak detection devices, when there is a gas leak candidate area in which the gas concentration of the target gas based on the measurement result measured by the gas sensor while the moving body is moving through the target area at a first speed while maintaining a first altitude, the movement control unit may control the movement of the moving body so that the moving body moves through the gas leak candidate area at a second speed slower than the first speed while maintaining a second altitude different from the first altitude, or stops in the gas leak candidate area while maintaining the second altitude. The acquisition unit may acquire additional measurement results of the target gas measured by the gas sensor while the moving body moves through the gas leak candidate area at the second speed while maintaining the second altitude, or stops in the gas leak candidate area while maintaining the second altitude. The detection unit may identify the gas leak candidate area as the gas leak point when the gas concentration of the target gas based on the additional measurement result satisfies a second condition.

[0009] In any of the gas leak detection devices, the movement control unit may control the movement of the moving object so that the moving object moves through the target area a plurality of times, and the detection unit may detect a leak of the target gas for each area based on a gas concentration of the target gas based on the measurement result for each area within the target area.

[0010] In any of the gas leak detection devices, the detection unit may detect a leak of the target gas for each area based on an average value of the gas concentration of the target gas in each area based on the measurement results for each area within the target area.

[0011] In any of the gas leak detection devices, the detection unit may detect a leak of the target gas based on a rate of change in gas concentration of the target gas based on the measurement results measured by the gas sensor while the moving body is moving.

[0012] The detection unit detects a leak of the target gas based on the degree of deviation of the gas concentration of the target gas based on the measurement results measured by the gas sensor while the moving body is moving, and the degree of deviation may be calculated based on the degree of deviation of the gas concentration data of the target gas from a statistical average.

[0013] In any of the gas leak detection devices, the detection unit may detect a leak of the target gas for each area based on a comparison between the gas concentration of each of the target gases based on the measurement results for each area within the target area and an average gas concentration of the target gas based on the measurement results for all areas of the target area.

[0014] Any of the gas leak detection devices may further include a reception unit that receives a spatial resolution of the gas leak detection. The movement control unit may control the movement of the moving body so that the moving body moves at a speed based on the spatial resolution.

[0015] In any of the gas leak detection devices, the acquisition unit may further acquire measurement results of the target gas measured by the gas sensor while the mobile object is moving outside the target area. The gas leak detection device may further include a calibration unit that calibrates the gas sensor based on the measurement results outside the target area.

[0016] In any of the gas leak detection devices, the movement control unit may control the moving object so that the moving object repeatedly moves to the gas leak point. The acquisition unit may acquire the measurement result of the target gas measured by the gas sensor each time the moving object moves to the gas leak point.

[0017] In any of the gas leak detection devices, the detection section may detect a leak of the target gas at the gas leak point each time the acquisition section acquires the measurement result at the gas leak point.

[0018] Any of the gas leak detection devices may further include an abnormality detection unit that detects an abnormality in the gas sensor when the gas concentration of the target gas based on the measurement results measured by the gas sensor while the moving body is moving does not change over a predetermined period of time.

[0019] Any of the gas leak detection devices may further include a correction unit that corrects errors in the measurement results of the target gas measured by the gas sensor due to noise generated in conjunction with the driving of the driving source of the moving body, with a correction amount according to the speed of the moving body.

[0020] In any of the gas leak detection devices, the moving object may further include a wind vane and anemometer. The movement control unit may control the movement of the moving object so that the moving object moves in a direction from downwind to upwind in the target area based on a measurement result of the wind vane and anemometer.

[0021] In any of the gas leak detection devices, the gas sensor may be an optical gas sensor.

[0022] A gas leak detection system according to one aspect of the present invention may include any one of the gas leak detection devices, a drive source controlled by the gas leak detection device, and a moving object having the gas sensor.

[0023] In the gas leak detection system, the mobile body may be an unmanned aerial vehicle.

[0024] In any of the gas leak detection systems, the gas sensor may be provided on a ceiling surface of a main body of the moving object.

[0025] In any one of the gas leak detection systems, the target gas inlet of the gas sensor may be provided on the ceiling surface so as to face the front side when the movable body moves forward.

[0026] In any one of the gas leak detection systems, the target gas inlet of the gas sensor may be provided on the ceiling surface so as to face toward the ceiling surface when the moving body moves upward.

[0027] Any of the gas leak detection systems may include a plurality of the mobile bodies. The plurality of mobile bodies may measure the gas concentration of the target gas with the gas sensor while moving in at least one assigned target area among a plurality of target areas included in a total target area. The gas leak detection system may include a distribution generation unit that generates gas distribution information of the target gas in the total target area based on the measurement results of the target areas provided by the plurality of mobile bodies. The distribution generation unit may generate the gas distribution information by deriving a baseline correction distribution of gas concentration so as to minimize a residual between the measurement results of the target areas provided by each of the mobile bodies moving in the target area and each of the measurement results of the target areas provided by each of the mobile bodies.

[0028] In any of the gas leak detection systems, a plurality of the mobile objects may be included, and the plurality of the mobile objects may measure the gas concentration of the target gas with the gas sensor while moving in at least one assigned target area among a plurality of target areas included in a total target area. The gas leak detection system may include a distribution generating unit that generates gas distribution information of the target gas in the total target area based on the measurement results of the respective target areas provided by the plurality of mobile objects.

[0029] In any of the gas leak detection systems, each of the plurality of target areas may have an overlapping area that overlaps with an adjacent target area, and the distribution generating unit may generate the gas distribution information by deriving the gas concentration of the target gas in the overlapping area based on each measurement result provided by each of the mobile objects moving through the overlapping area.

[0030] In any of the gas leak detection systems, the distribution generation unit may generate the gas distribution information by deriving a gas concentration that minimizes the residual with respect to each group of measurement results in the overlapping area provided from each of the moving bodies moving in the overlapping area.

[0031] Any of the gas leak detection methods may include a step of controlling movement of a mobile object equipped with a gas sensor. The gas leak detection method may include a step of acquiring a measurement result of a target gas measured by the gas sensor while the mobile object is moving in a target area and a response time from when the gas sensor starts measuring to when the gas sensor outputs the measurement result. The gas leak detection method may include a step of detecting a leak of the target gas in the target area based on the measurement result and the response time.

[0032] A program according to an aspect of the present invention may cause a computer to function as a movement control unit that controls the movement of a moving object equipped with a gas sensor. The program may cause the computer to function as an acquisition unit that acquires measurement results of a target gas measured by the gas sensor while the moving object is moving in a target area and a response time from when the gas sensor starts measuring to when it outputs the measurement results. The program may cause the computer to function as a detection unit that detects a leak of the target gas in the target area based on the measurement results and the response time.

[0033] The above summary of the invention does not list all of the features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0034] [Figure 1] 1 is a diagram showing an example of the overall configuration of a gas leak detection system according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram illustrating an example of functional blocks of an unmanned aerial vehicle (UAV). [Diagram 3] FIG. 2 is a diagram illustrating an example of a functional block of the gas leak detection device. [Figure 4A] FIG. 13 is a diagram showing an example of gas concentration distribution information that has not been corrected based on response time. [Figure 4B] FIG. 13 is a diagram showing an example of gas concentration distribution information corrected based on response time. [Diagram 5] FIG. 13 is a diagram showing an example of changes in gas concentration depending on the coordinate (time). [Figure 6] 10 is a flowchart showing an example of a gas leak detection procedure. [Figure 7] FIG. 1 is a diagram for explaining a gas leak detection method using multiple UAVs. [Figure 8] FIG. 2 illustrates an example of a hardware configuration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0036] 1 shows an example of the overall configuration of a gas leak detection system according to this embodiment. The gas leak detection system includes an unmanned aerial vehicle (UAV) 10 and a remote control device 300.

[0037] The UAV 10 includes a UAV body 20, a gimbal 50, a plurality of imaging devices 60, an imaging device 30, and a gas sensor 70. The UAV 10 is an example of a moving body. The moving body is a concept that includes an aircraft moving in the air, a vehicle moving on the ground, a ship moving on the water, and the like. The aircraft moving in the air is a concept that includes, in addition to a UAV, other aircraft, airships, helicopters, and the like that move in the air.

[0038] The UAV body 20 includes a plurality of rotors. The plurality of rotors are an example of a propulsion unit. The UAV body 20 flies the UAV 10 by controlling the rotation of the plurality of rotors. The UAV body 20 flies the UAV 10 using, for example, four rotors. The number of rotors is not limited to four. The UAV 10 may also be a fixed-wing aircraft that does not have rotors.

[0039] The gas sensor 70 detects the gas concentration of the gas to be measured. The gas sensor 70 may be an optical gas sensor. The optical gas sensor may be a non-dispersive infrared (NDIR) gas sensor. The measurement principle of the gas sensor 70 may be a tunable diode laser absorption spectroscopy (TDLAS) method, a differential absorption LiDAR (DIAL) method, a time correlated single photon counting (TCSPC) method, a photoacoustic method, a semiconductor method, a solid electrolyte method, a thermal conduction method, an acoustic wave method, an optical gas imaging method, or a capacitance method.

[0040] The gas sensor 70 may include a statistical processing unit that performs statistical processing on the measurement results. The statistical processing may be to generate statistical information including at least one of an average value, a maximum value, a minimum value, a variance, a moment, and a histogram from the measurement results.

[0041] The gas to be measured may be a combustible gas such as methane, propane, ethanol, hydrogen, ethylene, MCH (methylcyclohexane), etc. The gas to be measured may be a toxic gas such as carbon monoxide, hydrogen sulfide, formaldehyde, ammonia, etc. The gas to be measured may be a greenhouse gas such as carbon dioxide, nitrous oxide, refrigerant gas, etc.

[0042] The gas sensor 70 may be provided on the ceiling surface of the UAV body 20. The gas sensor 70 has an inlet 72 for taking in gas. The inlet 72 may be provided on the ceiling surface of the UAV body 20 so as to face the front side when the UAV 10 moves forward. If the gas concentration of the gas to be measured is measured while the UAV 10 moves upward, the inlet 72 may be provided on the ceiling surface of the UAV body 20 so as to face the ceiling surface side when the UAV 10 moves upward. The gas sensor 70 may have a drive mechanism for changing the attitude with respect to the UAV body 20 so that the orientation of the inlet 72 of the gas sensor 70 changes according to the movement direction of the UAV 10. The gas sensor 70 may have a plurality of inlets including inlets in different directions, and may have a switching mechanism for switching the inlet for taking in the gas to be measured from among the plurality of inlets according to the movement direction of the UAV 10. The inlet of the gas sensor 70 may be a hemispherical inlet capable of taking in gas from a plurality of directions.

[0043] The UAV 10 may have an arm extending from the UAV body 20 for carrying the gas sensor 70, and the gas sensor 70 may be provided at the tip of the arm.

[0044] When the moving body mounting the gas sensor 70 uses an internal combustion engine as a driving source, the intake port of the gas sensor 70 may be provided at a position separated from the exhaust port that discharges exhaust gas from the internal combustion engine. When the exhaust port is provided at the rear of the moving body, the intake port of the gas sensor 70 may be provided at the front of the moving body. The driving source of the moving body mounting the gas sensor 70 may be a motor. In the case of a motor, since no exhaust gas is generated from the driving source, the operation of the gas sensor is not hindered, and the gas concentration can be accurately measured, resulting in a short measurement time.

[0045] The imaging device 30 captures an image of an object included in a desired imaging range. The gimbal 50 rotatably supports the imaging device 30. The gimbal 50 is an example of a support mechanism. The gimbal 50 may change the attitude of the imaging device 30 by rotating the imaging device 30 about at least one of a yaw axis, a pitch axis, and a roll axis.

[0046] The multiple imaging devices 60 are sensing cameras that capture images of the surroundings of the UAV 10 to control the flight of the UAV 10. Two imaging devices 60 may be provided on the front, which is the nose of the UAV 10. Two other imaging devices 60 may be provided on the bottom of the UAV 10. The two imaging devices 60 on the front side may be paired and function as a so-called stereo camera. The two imaging devices 60 on the bottom side may also be paired and function as a stereo camera. The imaging device 60 may measure the presence of an object included in the imaging range of the imaging device 60 and the distance to the object. The imaging device 60 is an example of a measuring device that measures an object present in the imaging direction of the imaging device 30. The measuring device may be another sensor such as an infrared sensor or an ultrasonic sensor that measures an object present in the imaging direction of the imaging device 30. Based on images captured by the multiple imaging devices 60, three-dimensional spatial data of the surroundings of the UAV 10 may be generated. The number of imaging devices 60 provided in the UAV 10 is not limited to four. The UAV 10 may be equipped with at least one imaging device 60. The UAV 10 may be equipped with at least one imaging device 60 on each of the nose, tail, side, bottom, and ceiling surfaces of the UAV 10. The angle of view that can be set by the imaging device 60 may be wider than the angle of view that can be set by the imaging device 30. The imaging device 60 may have a single focus lens or a fisheye lens. The imaging device 30 may be an infrared camera. The imaging device 60 may be an infrared camera.

[0047] The remote control device 300 communicates with the UAV 10 to remotely control the UAV 10. The remote control device 300 may wirelessly communicate with the UAV 10. The remote control device 300 transmits instruction information indicating various commands related to the movement of the UAV 10, such as ascent, descent, acceleration, deceleration, forward movement, reverse movement, and turning, to the UAV 10. The instruction information includes, for example, instruction information to increase the altitude of the UAV 10. The instruction information may indicate the altitude at which the UAV 10 should be located. The UAV 10 moves to be located at the altitude indicated by the instruction information received from the remote control device 300. The instruction information may include an ascent command to increase the UAV 10. The UAV 10 increases while the ascent command is being received. The remote control device 300 is an example of a gas leak detection device that detects a gas leak in a target area of ​​a gas production, transportation, storage, and consumption facility for gas detection based on the measurement results from the gas sensor 70. The gas production, transportation, storage and consumption facility may be, for example, a natural gas field or a pipeline 200 .

[0048] The remote control device 300 may control the movement of the UAV 10 so that the UAV 10 moves in the target area according to a predetermined movement route. The remote control device 300 may control the flight of the UAV 10 so that the UAV 10 flies at a predetermined altitude in the target area according to a predetermined flight route. The remote control device 300 may control the flight of the UAV 10 so that the UAV 10 ascends or descends at each of a plurality of measurement points in the target area. The remote control device 300 may control the flight of the UAV 10 so that the UAV 10 ascends or descends while turning at each of a plurality of measurement points in the target area.

[0049] According to the gas leak detection system configured in this manner, the UAV 10 detects the gas concentration of the target gas with the gas sensor 70 while moving through a target area for gas detection such as a pipeline 200, and the remote control device 300 detects a gas leak in the target area based on the gas concentration measured by the gas sensor 70. This makes it possible to shorten the time required to complete inspection for gas leaks in the entire area to be detected.

[0050] In this embodiment, an example will be described in which the remote control device 300 functions as a gas leak detection device, a gas concentration measurement device that measures the concentration of a gas, or a control device that controls the UAV 10. However, the UAV 10 may function as a gas leak detection device. Alternatively, a device that can communicate with the UAV 10 other than the UAV 10 and the remote control device 300 may function as a gas leak detection device.

[0051] 2 shows an example of functional blocks of the UAV 10. The UAV 10 includes a UAV control unit 100, a memory 32, a communication interface 36, a propulsion unit 40, a GPS receiver 41, an inertial measurement unit 42, a magnetic compass 43, a barometric altimeter 44, a temperature sensor 45, a humidity sensor 46, a gimbal 50, an image capture device 60, an image capture device 30, a gas sensor 70, and a wind direction and speed meter 80.

[0052] The communication interface 36 communicates with other devices such as the remote control device 300. The communication interface 36 may receive instruction information including various commands for the UAV control unit 100 from the remote control device 300. The memory 32 stores programs and the like required for the UAV control unit 100 to control the propulsion unit 40, the GPS receiver 41, the inertial measurement unit (IMU) 42, the magnetic compass 43, the barometric altimeter 44, the temperature sensor 45, the humidity sensor 46, the gimbal 50, the imaging device 60, the imaging device 30, the gas sensor 70, and the wind vane and anemometer 80. The memory 32 may be a computer-readable recording medium and may include at least one of SRAM, DRAM, EPROM, EEPROM (registered trademark), and a flash memory such as a USB memory. The memory 32 may be provided inside the UAV body 20. It may be provided removable from the UAV body 20.

[0053] The UAV control unit 100 controls the flight, imaging, and measurement by various sensors of the UAV 10 according to a program stored in the memory 32. The UAV control unit 100 may be configured with a microprocessor such as a CPU or MPU, a microcontroller such as an MCU, etc. The UAV control unit 100 controls the flight, imaging, and measurement of the UAV 10 according to commands received from the remote control device 300 via the communication interface 36.

[0054] The propulsion unit 40 propels the UAV 10. The propulsion unit 40 has a plurality of rotors and a plurality of drive motors that rotate the plurality of rotors. The propulsion unit 40 rotates the plurality of rotors via the plurality of drive motors in accordance with commands from the UAV control unit 100 to fly the UAV 10.

[0055] The GPS receiver 41 receives a plurality of signals indicating time transmitted from a plurality of GPS satellites. The GPS receiver 41 calculates the position (latitude and longitude) of the GPS receiver 41, that is, the position (latitude and longitude) of the UAV 10 based on the plurality of received signals. In addition, RTK (REAL TIME KINEMATIC) or SLAM (SIMULATANEOUS LOCALIZATION AND MAPPING) may be used to calculate the position of the UAV 10. When RTK is used for position calculation, a base station may be installed in the production, transportation, storage, and consumption facility of the target gas. The IMU 42 detects the attitude of the UAV 10. The IMU 42 detects the acceleration in three axial directions of the UAV 10, i.e., forward / backward, left / right, and up / down, and the angular velocity in three axial directions of the UAV 10, i.e., pitch, roll, and yaw, as the attitude of the UAV 10. The magnetic compass 43 detects the heading direction of the UAV 10. The barometric altimeter 44 detects the altitude at which the UAV 10 flies. The barometric altimeter 44 detects the barometric pressure around the UAV 10 and converts the detected barometric pressure into altitude to detect the altitude. The temperature sensor 45 detects the temperature around the UAV 10. The humidity sensor 46 detects the humidity around the UAV 10.

[0056] The gas sensor 70 may be an NDIR gas sensor that detects the gas concentration of the measurement target gas. The anemometer 80 measures the wind direction and wind speed relative to the UAV 10.

[0057] 3 is a functional block diagram of a remote control device 300. The remote control device 300 may include a computer having a central processing unit (CPU) and a memory. The remote control device 300 may include a transmitter 301 that transmits control commands to the UAV 10 to control the flight of the UAV 10 in response to a user's operation.

[0058] The computer may be a personal computer, a tablet computer, a smartphone, a workstation, a server computer, a general-purpose computer, or a computer system in which multiple computers are connected. Such a computer system is also a computer in a broad sense. The computer may be a dedicated computer designed for controlling the UAV 10, or may be dedicated hardware realized by a dedicated circuit. The computer may be implemented by a virtual computer environment. When a computer is used, the remote control device 300 is realized by executing a program by the computer.

[0059] The remote control device 300 includes a control unit 310, a memory 330, and a communication interface 340. The remote control device 300 functions as a gas leak detection device. The control unit 310 may be configured with a CPU. The memory 330 stores various programs related to the movement control of the UAV 10 by the remote control device 300 and the control of gas leak detection.

[0060] The control unit 310 has a movement control unit 312, an acquisition unit 314, a detection unit 316, a reception unit 318, a calibration unit 320, an abnormality detection unit 322, a correction unit 324, and a distribution generation unit 326. In this embodiment, an example will be described in which the control unit 310 of the remote operation device 300 has the movement control unit 312, the acquisition unit 314, the detection unit 316, the reception unit 318, the calibration unit 320, the abnormality detection unit 322, the correction unit 324, and the distribution generation unit 326. However, at least one of the movement control unit 312, the acquisition unit 314, the detection unit 316, the reception unit 318, the calibration unit 320, the abnormality detection unit 322, the correction unit 324, and the distribution generation unit 326 may be included in a control unit of another device other than the remote operation device 300 that is connected to the remote operation device 300 via a network. For example, the movement control unit 312, the acquisition unit 314, and the detection unit 316 may be included in the control units of different devices.

[0061] The movement control unit 312 controls the movement of the UAV 10. The movement control unit 312 controls the movement of the UAV 10 so that the UAV 10 flies at a predetermined altitude along a predetermined flight route. The movement control unit 312 controls the movement of the UAV 10 so that the UAV 10 flies at a latitude, longitude, and altitude along the predetermined flight route. The movement control unit 312 may transmit a control command to the UAV 10 indicating the latitude, longitude, and altitude along the predetermined flight route. The movement control unit 312 may transmit a control command to the UAV 10 to feedback control the latitude, longitude, and altitude of the UAV 10 so that the UAV 10 flies at a predetermined flight route based on the position information of the UAV 10 indicating the latitude, longitude, and altitude of the UAV 10 from the UAV 10.

[0062] The movement control unit 312 may calculate the speed of the UAV 10 when controlling the movement of the UAV 10. When the movement control unit 312 calculates the speed of the UAV 10, the amount of positional displacement per unit time may be determined from GPS position information, the integral value of acceleration may be determined, the speed may be estimated from power input information to the propulsion unit 40, the speed may be calculated from the measurement value of an anemometer, or the speed may be estimated by performing these in a composite manner. For example, a Kalman filter may be used as the composite calculation.

[0063] If a no-fly zone exists in part of the target area, the movement control unit 312 may control the movement of the UAV 10 so that the UAV 10 flies while avoiding the no-fly zone.

[0064] The acquisition unit 314 acquires the measurement results of the target gas measured by the gas sensor 70 while the UAV 10 is moving in the target area. While the UAV 10 is moving, it does not mean a state in which the UAV 10 is hovering and maintaining a constant latitude, longitude, and altitude, but a state in which the UAV 10 is ascending, descending, accelerating, decelerating, moving forward, backward, or turning.

[0065] The acquisition unit 314 may further acquire, from the UAV 10, position information of the UAV 10 when the measurement result is acquired from the gas sensor 70. The position information may be the position of the UAV 10 at any time between the start of measurement and the end of measurement in one gas concentration measurement by the gas sensor 70. The position information may indicate the position of the UAV 10 at the start of measurement in one gas concentration measurement by the gas sensor 70. The position information may indicate the position of the UAV 10 at the end of measurement in one gas concentration measurement by the gas sensor 70. The position information may indicate the position of the UAV 10 at an intermediate time between the start of measurement and the end of measurement in one gas concentration measurement by the gas sensor 70. In the case where the gas sensor 70 has a response time T from when the gas sensor 70 starts measurement to when it outputs a measurement result due to gas replacement or the like, the acquisition unit 314 may acquire the response time T. The response time T is the time from when the gas sensor 70 starts measurement to when it outputs the measurement result, and may be a displacement time calculated from the diffusion coefficient of the target gas and the shape of the gas chamber of the gas sensor 70, or may be a response delay time caused by signal processing, particularly a response delay time of signal processing by time moving average / smoothing processing, or may be a combination of these.

[0066] The response time T may be input from the outside, may be a preset value or formula, or may be estimated for each individual based on the measurement results of the gas sensor 70. For example, the gas concentration distribution in the same area may be acquired under multiple conditions (speed, moving direction, wind direction), and the response time T may be used as a parameter to optimize the gas concentration distributions acquired under the multiple conditions so that they match, thereby determining the response time T. The acquisition unit 314 may correct the measurement time by the response time T. In addition, the acquisition unit 314 may correct the position information at a certain time in consideration of the response time. Specifically, the correction may be subtracting the response time T from the time t. This allows the distribution generation unit 326 described later to more accurately calculate the distribution of the target gas at a certain time.

[0067] For example, in relation to the movement direction of the UAV 10 and the wind direction, the movement direction of the UAV 10 may cause a shift in the correspondence between the position information and the measurement result. FIG. 4A shows an example of gas concentration distribution information generated by the distribution generating unit 326 without correcting the measurement time of the gas sensor 70 by the response time T. As shown in FIG. 4A, when the distribution generating unit 326 generates gas concentration distribution information based on the measurement result of the gas sensor 70 measuring the gas concentration while the UAV 10 moves along the flight path 550, a shift in the correspondence between the position information and the measurement result may occur in the region 552 where the movement direction of the UAV 10 is the opposite direction. In such a case, the acquiring unit 314 may correct the measurement time by the response time T. The acquiring unit 314 may correct the measurement time by the response time T to eliminate the shift in the correspondence between the position information and the measurement result due to the difference in the movement direction of the UAV 10. As a result, the distribution generating unit 326 can generate gas concentration distribution information by eliminating the mismatch between the position information and the measurement results in the area 552 where the movement direction of the UAV 10 is the opposite direction, as shown in FIG. 4B. Whether or not to perform the correction based on the response time may be specified by the user. For example, the gas concentration distribution information before the correction based on the response time may be displayed on the display unit, and the user may select whether or not to perform the correction based on the response time. When the user selects the correction based on the response time, the acquiring unit 314 may correct the measurement time by the response time T.

[0068] The acquisition unit 314 may also correct the position information at a certain time in consideration of the speed of the UAV 10. For example, if the position vector indicating the position information of the UAV 10 is x, the speed vector of the UAV 10 is v, the response time of the gas sensor 70 is T, and the corrected position vector indicating the corrected position information of the UAV 10 is xc, then xc=x-vT may be obtained. Also, x, v, and T may be information obtained by statistically processing the measurement results. Also, the speed vector v may be the difference between the speed vector of the UAV 10 and the vector of the wind direction. Also, the corrected position vector xc is the corrected position information of the UAV 10 and at the same time, the corrected position coordinates of each measurement result of the gas sensor 70. In correcting each xc, v and T at each x and each time t may be estimated and corrected using data in the spatial and temporal vicinity. More specifically, each x and v and T at each time t may be predicted and corrected using data assimilation and inverse analysis.

[0069] The acquisition unit 314 may further acquire from the UAV 10 measurement results of the wind direction and wind speed relative to the UAV 10 from the anemometer 80. The acquisition unit 314 may further acquire environmental information indicating the environmental condition around the UAV 10. The acquisition unit 314 may further acquire from the UAV 10 environmental information indicating the temperature around the UAV 10 measured by the temperature sensor 45 and the humidity around the UAV 10 measured by the humidity sensor 46.

[0070] The movement control unit 312 may control the movement of the UAV 10 so that the UAV 10 moves in the target area from downwind to upwind based on the measurement results of the anemometer 80.

[0071] The detection unit 316 detects a leak of the target gas in the target area based on the measurement result of the gas sensor 70. The accuracy of the measurement result measured by the gas sensor 70 may change depending on the environment around the gas sensor 70, such as temperature and humidity. Therefore, when the environment around the gas sensor 70, such as temperature and humidity, satisfies a predetermined condition, the detection unit 316 may detect a leak of the target gas in the target area based on the measurement result of the gas sensor 70. The detection unit 316 may identify a gas leak point where the leak of the target gas is detected in the target area based on the measurement result of the gas sensor 70 and the position information of the UAV 10. The detection unit 316 may identify a gas leak point where the leak of the target gas is detected in the target area based on the measurement result and response time of the gas sensor 70 and the position information of the UAV 10. The detection unit 316 may correct the position information at a certain time based on the response time. The detection unit 316 may identify the gas leak point based on position information of a time before the response time of the gas sensor 70 from the time when the gas sensor 70 outputs the measurement result. In other words, the detection unit 316 may identify the gas leak point based on position information of a time obtained by subtracting the response time T of the gas sensor 70 from the time when the gas sensor 70 outputs the measurement result.

[0072] When the gas sensor 70 measures the gas concentration while the UAV 10 is moving, the measurement accuracy of the gas sensor 70 may be reduced compared to when the gas sensor 70 measures the gas concentration while the UAV 10 is hovering.

[0073] Therefore, the detection unit 316 first detects a gas leak candidate area where there is a possibility of gas leakage based on the measurement result measured by the gas sensor 70 while the UAV 10 moves in the gas leak candidate area at a second speed slower than the first speed, or based on the measurement result measured by the gas sensor 70 while the UAV 10 moves in the gas leak candidate area at a second speed slower than the first speed, or while the UAV 10 is stopped in the gas leak candidate area, and may identify a gas leak point from the gas leak candidate area. The size of the gas leak point may be determined based on the distance traveled by the UAV 10 during one measurement of the target gas by the gas sensor 70. The size of the gas leak point may be an area within a predetermined radius centered on the position of the UAV 10. The predetermined radius may be determined based on the altitude at which the UAV 10 flies during the measurement by the gas sensor 70. The predetermined radius may be determined based on the height from the target object of the gas leak to the UAV 10. The predetermined radius may be smaller as the height from the target object of the gas leak to the UAV 10 is lower. That is, the closer the UAV 10 is to the object of gas leak detection, the smaller the predetermined radius may be.

[0074] The movement control unit 312 causes the gas sensor 70 to measure the gas concentration at a first spatial resolution while moving the UAV 10 at a first speed. The detection unit 316 determines whether or not there is a gas leak candidate area in which the gas concentration of the target gas based on the measurement result measured by the gas sensor 70 while the UAV 10 is moving at the first speed satisfies a first condition. If the gas concentration of the target gas is equal to or greater than a first threshold, the detection unit 316 may determine that there is a gas leak candidate area in which the gas concentration satisfies the first condition. If there is a gas leak candidate area, the movement control unit 312 controls the movement of the UAV 10 to move through the gas leak candidate area at a second speed slower than the first speed, or to stay in the gas leak candidate area.

[0075] The movement control unit 312 may control the movement of the UAV 10 so that the gas concentration is measured by the gas sensor 70 while ascending or descending the UAV 10. The movement control unit 312 may control the movement of the UAV 10 so that the UAV 10 ascends or descends while turning. This makes it difficult for gas to be taken into the intake port of the gas sensor 70 due to downwash, and prevents the gas concentration from being unable to be measured accurately.

[0076] The acquisition unit 314 acquires additional measurement results of the target gas measured by the gas sensor 70 while the UAV 10 moves through the gas leak candidate area at a second speed or stops in the gas leak candidate area. The detection unit 316 determines whether the gas concentration of the target gas based on the additional measurement results satisfies a second condition. The detection unit 316 may determine that the gas concentration satisfies the second condition when the gas concentration of the target gas based on the additional measurement results is equal to or greater than a second threshold. The second threshold may be the same as the first threshold. Or, the second threshold may be higher than the first threshold. When the gas concentration of the target gas based on the additional measurement results satisfies the second condition, the detection unit 316 identifies the gas leak candidate area as a gas leak point.

[0077] Due to the difference in weight between the target gas and air, the gas concentration may change depending on the altitude. Therefore, the detection unit 316 first detects a gas leak candidate area where there is a possibility of gas leakage based on the measurement results measured by the gas sensor 70 while the movement control unit 312 moves the UAV 10 at a first speed while maintaining the first altitude in the target area. Next, the detection unit 316 may identify a gas leak point from within the gas leak candidate area based on the measurement results measured by the gas sensor 70 while the UAV 10 moves through the gas leak candidate area at a second speed slower than the first speed while maintaining a second altitude different from the first altitude, or while the UAV 10 is parked in the gas leak candidate area while maintaining the second altitude.

[0078] The second altitude may be lower than the first altitude and the second threshold may be higher than the first threshold because the gas of interest tends to be distributed over a wider area at higher altitudes due to natural diffusion.

[0079] If the gas of interest is heavier than air, the second altitude may be lower than the first altitude and the second threshold may be higher than the first threshold, and if the gas of interest is lighter than air, the second altitude may be higher than the first altitude and the second threshold may be higher than the first threshold.

[0080] When there is a gas leak candidate area in which the gas concentration of the target gas based on the measurement result measured by the gas sensor 70 while the UAV 10 is moving through the target area at the first speed while maintaining the first altitude, the movement control unit 312 may control the movement of the UAV 10 so that the UAV 10 moves through the gas leak candidate area at a second speed slower than the first speed while maintaining a second altitude different from the first altitude, or stays in the gas leak candidate area while maintaining the second altitude. The acquisition unit 314 may acquire additional measurement results of the target gas measured by the gas sensor 70 while the UAV 10 moves through the gas leak candidate area at the second speed while maintaining the second altitude, or stays in the gas leak candidate area while maintaining the second altitude. The detection unit 316 may identify the gas leak candidate area as a gas leak point when the gas concentration of the target gas based on the additional measurement result satisfies the second condition.

[0081] When the detection unit 316 identifies the gas leak point, the acquisition unit 314 may cause the imaging device 30 to capture an image of the gas leak point and acquire the captured image from the UAV 10 as an image of the gas leak point. When the target gas has light absorption characteristics in the infrared region, the imaging device 30 may be an infrared imaging device (infrared camera). When the target gas emits light in a specific wavelength band, the imaging device 30 may be an imaging device sensitive to that wavelength band. Specifically, when the target gas is hydrogen, ultraviolet light is emitted when it is burned, so the imaging device 30 may be an ultraviolet camera.

[0082] The movement control unit 312 may control the movement of the UAV 10 so that the UAV 10 moves through the target area multiple times. The movement control unit 312 may control the flight of the UAV 10 so that the UAV 10 flies through the target area multiple times along a predetermined flight route. The detection unit 316 may detect a target gas leak for each area based on the gas concentration of the target gas based on the measurement results of each area in the target area. The detection unit 316 may detect a target gas leak for each area based on the average value of the gas concentration of the target gas for each area based on the measurement results of each area in the target area. For example, as shown in FIG. 5, the detection unit 316 may detect an area as a gas leak point where the difference ΔC between the average value Cav of the gas concentration of the target gas for each area based on the measurement results of each area in the target area is equal to or greater than a threshold value. The detection unit 316 may detect the area as a gas leak point after confirming that ΔC is reproduced within a certain standard when moving through the target area multiple times.

[0083] The detection unit 316 may detect a leak of the target gas based on a rate of change in the gas concentration of the target gas based on the measurement results measured by the gas sensor 70 while the UAV 10 is moving. The detection unit 316 may detect a leak of the target gas when a rate of change in the gas concentration of the target gas based on the measurement results measured by the gas sensor 70 while the UAV 10 is moving is equal to or greater than a threshold. The detection unit 316 may detect a leak of the target gas based on a differential value of the gas concentration of the target gas based on the measurement results measured by the gas sensor 70 while the UAV 10 is moving.

[0084] The detection unit 316 may perform statistical processing of the gas concentration data of the target gas based on the measurement results measured by the gas sensor 70 while the UAV 10 is moving, calculate a deviation degree as the degree of deviation from the statistical average for the gas concentration data of the target gas obtained every moment, and detect a gas leak based on the deviation degree. Specifically, the deviation degree is calculated by calculating the average value μ or variance σ of the gas concentration data of the target gas or the data of the rate of change of the gas concentration data of the target gas at a time or position in an appropriate section. 2 Calculate the deviation α=(x-μ) for the new gas concentration data x. 2 / σ2 If the deviation defined in this way exceeds an appropriate threshold, the new gas concentration data x may be judged as being statistically abnormal and detected as a leak of the target gas, and the threshold may be 9, 16, or 36.

[0085] The detection unit 316 may detect a leak of the target gas for each area based on a comparison between the gas concentration of the target gas based on the measurement results for each area in the target area and the average gas concentration of the target gas based on the measurement results for all areas in the target area. The detection unit 316 may detect an area in which the gas concentration is higher than the average gas concentration of the target gas based on the measurement results for all areas in the target area by a threshold or more as a gas leak point of the target gas.

[0086] The detection unit 316 may detect the leakage of the target gas using at least one of the measurement information of the fixed gas sensor and the observation information of the artificial satellite, as well as the measurement results of the gas sensor 70 provided by the multiple UAVs 10. The measurement principle of the fixed gas sensor may be a non-dispersive infrared absorption method, a tunable diode laser absorption spectroscopy (TDLAS) method, a differential absorption LiDAR (DIAL) method, a time correlated single photon counting (TCSPC) method, a photoacoustic method, a semiconductor method, a solid electrolyte method, a thermal conduction method, a sound wave method, an optical gas imaging method, or a capacitance method. The observation information of the artificial satellite may be observation information of visible light, infrared rays, microwaves, etc. reflected or emitted from the ground, ocean, or atmosphere, or electromagnetic waves may be irradiated toward the observation target, and the reflected waves may be used as the observation information.

[0087] The reception unit 318 receives the spatial resolution of the gas leak detection. The spatial resolution may be the distance between two points where the measurement results of the gas sensor 70 are independent, or may be the size of one pixel when the gas distribution is indicated. The reception unit 318 receives the spatial resolution of the gas leak detection from the user. The movement control unit 312 controls the movement of the UAV 10 so that the UAV 10 moves at a speed based on the spatial resolution. The movement control unit 312 may derive m / T by dividing the spatial resolution (m) by a response time (T) indicating the time it takes for the gas sensor 70 to detect one gas concentration, and may determine the speed of the UAV 10 based on m / T. The movement control unit 312 may multiply the speed (v) of the UAV 10 by the response time (T) to determine the distance of the spatial resolution. The speed (v) may be a statistically processed speed during flight. For example, the statistical processing may be a time series average. The response time (T) is the time from when c starts measurement to when it outputs the measurement result, and may be the displacement time calculated from the diffusion coefficient of the target gas and the shape of the gas chamber of the gas sensor 70, or it may be the response delay time caused by signal processing, or it may be a combination of these.

[0088] The characteristics of the gas sensor 70 may change over time. Therefore, it is preferable that the gas sensor 70 is calibrated periodically. Therefore, in order to perform the calibration, the movement control unit 312 may periodically move the UAV 10 to an area outside the target area that is not affected by gas even if a gas leak occurs in the target area. When an error occurs in the measurement result of the gas sensor 70, the movement control unit 312 may move the UAV 10 to an area outside the target area that is not affected by gas even if a gas leak occurs in the target area.

[0089] The acquisition unit 314 may further acquire the measurement result of the target gas measured by the gas sensor 70 while the UAV 10 is moving outside the target area. The calibration unit 320 performs calibration of the gas sensor based on the measurement result outside the target area. The measurement result outside the target area is likely to match the gas concentration of the target gas in the case where no gas leakage occurs. Therefore, the calibration unit 320 determines a correction coefficient or a correction amount for correcting the measurement result of the gas sensor 70 so that the gas concentration based on the measurement result outside the target area matches a predetermined gas concentration of the target gas in the case where no gas leakage occurs. The detection unit 316 corrects and derives the gas concentration based on the measurement result by the gas sensor 70 based on the correction coefficient or the correction amount determined by the calibration unit 320.

[0090] When the correction coefficient or the correction amount determined by the calibration section 320 is large, there is a possibility that there is an abnormality in the gas sensor 70. Therefore, when the correction coefficient or the correction amount determined by the calibration section 320 is larger than a predetermined criterion, the calibration section 320 may not perform calibration and may output a warning signal indicating an abnormality in the gas sensor 70. Here, the calibration section 320 may dynamically set the predetermined criterion based on the correction amount of a calibration performed in the past.

[0091] In some cases, it may be preferable to continuously or periodically detect gas leaks in an area where a gas leak has occurred. Therefore, the movement control unit 312 may control the UAV 10 so that the UAV 10 repeatedly moves to the gas leak point. The acquisition unit 314 may acquire the measurement result of the target gas measured by the gas sensor 70 every time the UAV 10 moves to the gas leak point. The detection unit 316 may detect the leak of the target gas at the gas leak point every time the acquisition unit 314 acquires the measurement result of the gas leak point.

[0092] When an area with a high risk of gas leakage is set as a priority area, it may be preferable to perform gas leakage detection in a priority area in a priority area or periodically. Therefore, the movement control unit 312 may control the UAV 10 to move in a priority area or to move repeatedly. Specifically, the priority area may be a peripheral area of ​​at least one of a pipeline joint, a gas well mouth, a flare system, a vent mouth, a pumping device, and a chimney. The UAV 10 may fly at a first speed outside the priority area and fly at a second speed slower than the first speed in the priority area.

[0093] When the UAV 10 is measuring the gas concentration by the gas sensor 70 while moving, the gas concentration measured by the gas sensor 70 is likely to fluctuate because the gas concentration is not measured continuously at one point. If the gas concentration measured by the gas sensor 70 does not change even though the UAV 10 is measuring the gas concentration by the gas sensor 70 while moving, there is a possibility that the gas sensor 70 is abnormal. Therefore, the abnormality detection unit 322 detects an abnormality in the gas sensor 70 when the concentration of the target gas based on the measurement result measured by the gas sensor 70 while the UAV 10 is moving does not change for a predetermined period of time or the amount of change is within a predetermined range. This allows an abnormality in the gas sensor 70 to be discovered early.

[0094] When UAV 10 is flying outside the target area where no gas leaks are occurring, if the measurement result of the gas sensor 70 is higher than the specified value, or if the measurement result is not output, there is a high possibility that the gas sensor 70 is abnormal, so the abnormality detection unit 322 may detect an abnormality in the gas sensor 70.

[0095] The correction unit 324 corrects an error that occurs in the measurement result of the target gas measured by the gas sensor 70 due to noise generated by the driving source of the UAV 10, with a correction amount according to the speed of the UAV 10. The driving source is, for example, a motor for rotating a rotor. Noise such as electromagnetic noise generated by the driving of the motor may affect the signal indicating the measurement result output from the gas sensor 70, causing an error in the measurement result. Such noise tends to become larger as the rotation amount of the motor increases. That is, the magnitude of the noise tends to change according to the speed of the UAV 10. Therefore, the correction unit 324 may refer to the relationship information indicating the relationship between the speed of the UAV 10 and the correction amount, and correct the gas concentration based on the measurement result by the gas sensor 70 with the determined correction amount. The correction unit 324 may receive a correction instruction, refer to the relationship information indicating the relationship between the speed of the UAV 10 and the correction amount, and determine the correction amount according to the speed of the UAV 10, and correct the gas concentration based on the measurement result by the gas sensor 70 with the determined correction amount. If there is no instruction for correction, the correction unit 324 may derive the gas concentration based on the measurement result by the gas sensor 70 without correcting the measurement result by the gas sensor 70. For example, the gas concentration before correction may be displayed on a display unit provided in the remote control device 300, and if the user determines that the gas concentration is an abnormal value, a correction instruction may be given to the remote control device 300, and upon receiving the correction instruction, the correction unit 324 may refer to relationship information indicating the relationship between the speed of the UAV 10 and the correction amount, determine a correction amount according to the speed of the UAV 10, and correct the gas concentration based on the measurement result by the gas sensor 70 with the determined correction amount.

[0096] Furthermore, the gas sensor 70 may sample the gas at a frequency faster than the driving frequency of the driving source. By the gas sensor 70 sampling the gas at a frequency faster than the driving frequency of the driving source, the influence of electromagnetic noise generated from the driving source can be suppressed. For example, when the gas sensor 70 is an NDIR gas sensor, the influence of electromagnetic noise generated from the driving source can be suppressed by making the driving frequency of the light source faster than the driving frequency of the driving source.

[0097] 6 is a flowchart showing an example of a gas leak detection procedure. While the movement control unit 312 flies the UAV 10 at a first speed along a predetermined flight route in a target area, the acquisition unit 314 acquires a measurement result of the gas concentration measured by the gas sensor 70 (S100).

[0098] The detection unit 316 determines whether there is a gas leak candidate area where the gas concentration based on the measurement result is equal to or greater than the first threshold (S102). The detection unit 316 may identify a gas leak point where the gas concentration based on the measurement result is equal to or greater than the first threshold based on the position information of the UAV 10 acquired by the acquisition unit 314 together with the measurement result.

[0099] If a suspected gas leak area is present, the acquisition unit 314 acquires additional measurement results of the gas concentration measured by the gas sensor 70 while the movement control unit 312 is flying the UAV 10 over the suspected gas leak area at a second speed slower than the first speed (S104).

[0100] The detection unit 316 determines whether there is a gas leak candidate area where the gas concentration based on the additional measurement result is equal to or greater than a second threshold (S106). If there is a gas leak candidate area where the gas concentration is equal to or greater than the second threshold, the detection unit 316 identifies the gas leak candidate area where the gas concentration is equal to or greater than the second threshold as a gas leak point (S108).

[0101] Through this procedure, the detection unit 316 detects the presence or absence of a gas leak in the entire target area at a relatively low spatial resolution, and then detects the presence or absence of a gas leak in a more detailed manner at a relatively high spatial resolution in a gas leak candidate area where a gas leak is highly likely to occur. This makes it possible to detect the presence or absence of a gas leak in the entire target area at an early stage while preventing a decrease in the accuracy of the gas leak detection.

[0102] The distribution generating unit 326 may generate gas distribution information of the gas concentration in the target area based on each measurement result in the target area. The distribution generating unit 326 may identify a safe area where the human body is not affected based on the gas distribution information, and indicate the safe area in the gas distribution information.

[0103] When detecting gas leaks in a relatively large target area, such as a pipeline, if a single UAV 10 is used to detect gas leaks in the entire target area, it may take a long time to complete detection of gas leaks in the entire target area.

[0104] Therefore, the remote control device 300 may control the flight of multiple UAVs 10 so that the detection of gas leaks in the target area is shared among the multiple UAVs 10.

[0105] The multiple UAVs 10 may measure the target gas with the respective gas sensors 70 while flying in at least one assigned target area among the multiple target areas included in the total target area. That is, the movement control unit 312 may cause each of the multiple UAVs 10 to measure the gas concentration of the target gas with the respective gas sensors 70 while flying in at least one assigned target area among the multiple target areas included in the total target area.

[0106] 7, for example, a total target area 500 is divided into three target areas 501, 502, and 503, and a UAV 10 is assigned to each of the target areas 501, 502, and 503. Then, the movement control unit 312 flies each UAV 10 in each of the target areas 501, 502, and 503, and measures the gas concentration in the target areas 501, 502, and 503 with each gas sensor 70.

[0107] The distribution generation unit 326 generates gas distribution information of the target gas in the total target area based on the measurement results of the gas sensors 70 in each of the target areas 501, 502, and 503 provided by multiple UAVs 10.

[0108] 7, each of the multiple target areas 501, 502, and 503 may have overlapping areas 512 and 514 that overlap with adjacent target areas. In this case, the distribution generating unit 326 may generate gas distribution information by deriving the gas concentration of the target gas in the overlapping areas 512 and 514 based on the measurement results of the respective gas sensors 70 provided from the respective UAVs 10 moving through the overlapping areas 512 and 514. The distribution generating unit 326 may generate gas distribution information for the overlapping areas 512 and 514 based on the average value or distribution information of the gas concentration based on the measurement results of the respective gas sensors 70 provided from the respective UAVs 10 moving through the overlapping areas 512 and 514.

[0109] The distribution generating unit 326 may generate gas distribution information by deriving a gas concentration that minimizes the residual between each measurement result group in the overlapping area 512 provided from each UAV 10 moving through the overlapping area 512. The distribution generating unit 326 may generate gas distribution information by deriving a gas concentration that minimizes the sum of squares (sum of squares error) of the residual between each measurement result group in the overlapping area 512 provided from each UAV 10 moving through the overlapping area 512. For example, when a measurement result group of the gas sensor 70 in the overlapping area 512 included in the target area 501 is V501 and a measurement result group of the gas sensor 70 in the overlapping area 512 included in the target area 502 is V502, the distribution generating unit 326 may generate gas distribution information by determining a predicted gas concentration distribution VP so that the deviation between V501 and V502 is minimized. Specifically, the distribution generation unit 326 may generate the gas distribution information by calculating the residual between the predicted concentration distribution VP and each of V501 and V502, taking the sum of squares of the residuals, and calculating the predicted concentration distribution so as to minimize the sum of squares of the residuals; more specifically, when the predicted concentration VP is characterized by parameters, the distribution generation unit 326 may generate the gas distribution information by determining the parameters so as to minimize the sum of squares of the residuals.

[0110] The distribution generation unit 326 may derive a correction coefficient or a correction amount for correcting the measurement results of each gas sensor 70 so that the measurement results match each other by comparing the measurement results of each gas sensor 70 provided by each UAV 10 moving through the overlapping areas 512, 514. The distribution generation unit 326 may derive the gas concentration of the target area by correcting the measurement results of each target area with the correction coefficient or correction amount. This makes it possible to suppress errors in the measurement results between the gas sensors 70 and to suppress deviations in the gas concentration distribution at the boundary between the target areas.

[0111] For example, if the average value AV501 of the measurement results of the gas sensor 70 in the overlapping area 512 included in the target area 501 is taken as the average value AV502 of the measurement results of the gas sensor 70 in the overlapping area 512 included in the target area 502, then by subtracting (AV502-AV501) from the measurement results of the target area 502, the deviation in the gas concentration distribution at the boundary between the target areas can be suppressed.

[0112] The distribution generating unit 326 may generate gas distribution information by deriving a gas concentration that minimizes the residual with each measurement result group provided from each UAV 10 moving in each target area. The distribution generating unit 326 may generate gas distribution information by deriving a gas concentration that minimizes the sum of squares (sum of squares error) of the residual with each measurement result group provided from each UAV 10 moving in each target area. For example, when the measurement result group of the gas sensor 70 in the target area 501 is V501 and the measurement result group of the gas sensor 70 in the target area 502 is V502, the distribution generating unit 326 may estimate baseline corrected distribution information obtained when no gas is present so that the deviation between V501 and V502 is minimized, and generate gas distribution information from the difference between the baseline gas corrected distribution information and the data of the measurement result group. Specifically, the distribution generating unit 326 may assume a polynomial function or a Fourier series with respect to position as the baseline correction distribution, calculate the residual with each of V501 and V502, take the sum of squares of the residual, determine a baseline gas distribution that minimizes the sum of squares of the residual, and generate gas distribution information by taking the difference between the obtained gas concentration and the baseline correction distribution.

[0113] Furthermore, the distribution generating unit 326 may use the obtained gas concentration distribution and a calculation by CFD (computational fluid dynamics) to interpolate and predict the gas concentration distribution, and further calculate the total gas amount. Specifically, the distribution generating unit 326 may perform data assimilation between the gas concentration distribution obtained by the four-dimensional variation method and the predicted value of the gas concentration distribution obtained by the CFD calculation, to interpolate and predict the gas concentration distribution, and further calculate the total gas amount. The calculated total gas amount may be used as the leaked gas amount. In addition, when the gas concentration distribution is interpolated and predicted, and further, the total gas amount is calculated, an inverse analysis may be performed on the obtained gas concentration distribution by adjoint analysis, and it is assumed that the gas leak source is not dispersed but localized, and the more localized the predicted location probability distribution of the gas leak source is, the better the prediction accuracy is, added to the prediction index, and an entropy or average information amount for the predicted location probability distribution of the leak source may be added as a prediction index together with the error between the obtained gas concentration distribution and the predicted gas concentration distribution of the gas, and when the function of the predicted location probability distribution of the gas leak source is p(x) for position x, the entropy H may be H=-∫p(x)log(p(x)) (the integral is over the entire space).

[0114] The distribution generating unit 326 may calculate the gas concentration distribution or the total amount of gas using at least one of the measurement information of the fixed gas sensor and the observation information of the artificial satellite, as well as the measurement results of the gas sensor 70 provided by the multiple UAVs 10. The measurement principle of the fixed gas sensor may be a non-dispersive infrared absorption method, a tunable diode laser absorption spectroscopy (TDLAS) method, a differential absorption LiDAR (DIAL) method, a time correlated single photon counting (TCSPC) method, a photoacoustic method, a semiconductor method, a solid electrolyte method, a thermal conduction method, an acoustic method, an optical gas imaging method, or a capacitance method. The observation information of the artificial satellite may be observation information of visible light, infrared rays, microwaves, etc. reflected or radiated from the ground, ocean, or atmosphere, or electromagnetic waves may be irradiated toward the observation target, and the reflected waves may be used as the observation information.

[0115] The gas leak detection system may further include a reporting unit, and may electronically report the location of the gas leak or the amount of leaked gas related to the production, transportation, storage, and consumption facility of the target gas, and report it to the certification system. The certification system may certify the production, transportation, storage, and consumption facility of the target gas, or the business operator in charge of the production, transportation, storage, and consumption facility of the target gas, based on the reported electronic report. For example, if the amount of leaked gas in a certain period is equal to or less than a specified value, the certification system may certify the business operator in charge of the production, transportation, storage, and consumption facility of the target gas as a good business operator. In addition, the certification system may use operation information of the production, transportation, storage, and consumption facility of the target gas for certification. The operation information may be the type of gas, gas production amount, gas consumption amount, gas transportation amount, gas storage amount, time change in gas storage amount, operation time, energy consumption amount, self-generated power amount, purchased power amount, inspection record, repair record, and greenhouse gas emission amount. In addition, at least one of the reported electronic report and the certification result may be stored in a repository that can be referenced by a third party. For example, if the third party is a gas consumer, a good gas sales company may be selected based on the authentication results stored in the repository. The authentication system may also issue credits based on the difference between the amount of gas leaked in a certain period and a reference value. The credits may be, for example, carbon credits.

[0116] 8 shows an example of a computer 1200 in which aspects of the present invention may be embodied in whole or in part. A program installed on the computer 1200 may cause the computer 1200 to perform operations associated with an apparatus according to an embodiment of the present invention or one or more "parts" of the apparatus. Alternatively, the program may cause the computer 1200 to execute the operations or one or more "parts". The program may cause the computer 1200 to execute a process or steps of the process according to an embodiment of the present invention. Such a program may be executed by the CPU 1212 to cause the computer 1200 to execute specific operations associated with some or all of the blocks of the flowcharts and block diagrams described herein.

[0117] The computer 1200 according to this embodiment includes a CPU 1212 and a RAM 1214, which are connected to each other by a host controller 1210. The computer 1200 also includes a communication interface 1222 and an input / output unit, which are connected to the host controller 1210 via an input / output controller 1220. The computer 1200 also includes a ROM 1230. The CPU 1212 operates according to programs stored in the ROM 1230 and the RAM 1214, thereby controlling each unit.

[0118] The communication interface 1222 communicates with other electronic devices via a network. The hard disk drive may store programs and data used by the CPU 1212 in the computer 1200. The ROM 1230 stores a boot program executed by the computer 1200 when activated and / or a program that depends on the hardware of the computer 1200. The programs are provided via a computer-readable recording medium such as a CD-ROM, a USB memory, or an IC card, or a network. The programs are installed in the RAM 1214, which is also an example of a computer-readable recording medium, or the ROM 1230, and executed by the CPU 1212. The information processing described in these programs is read by the computer 1200, and brings about cooperation between the programs and the various types of hardware resources. An apparatus or method may be configured by implementing an operation or processing of information according to the use of the computer 1200.

[0119] For example, when communication is performed between the computer 1200 and an external device, the CPU 1212 may execute a communication program loaded in the RAM 1214 and instruct the communication interface 1222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads transmission data stored in a transmission buffer area provided in the RAM 1214 or a recording medium such as a USB memory, transmits the read transmission data to a network, or writes reception data received from the network to a reception buffer area or the like provided on the recording medium.

[0120] Furthermore, the CPU 1212 may cause all or a necessary portion of a file or database stored in an external recording medium such as a USB memory to be read into the RAM 1214, and may perform various types of processing on the data on the RAM 1214. The CPU 1212 may then write back the processed data to the external recording medium.

[0121] Various types of information, such as various types of programs, data, tables, and databases, may be stored in the recording medium and undergo information processing. The CPU 1212 may perform various types of processing on the data read from the RAM 1214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequence of the program, and write back the results to the RAM 1214. The CPU 1212 may also search for information in a file, database, etc. in the recording medium. For example, when a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, the CPU 1212 may search for an entry that matches a condition, in which the attribute value of the first attribute is specified, from among the plurality of entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0122] The above-described programs or software modules may be stored in a computer-readable storage medium on the computer 1200 or in the vicinity of the computer 1200. Also, a recording medium such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, thereby providing the programs to the computer 1200 via the network.

[0123] A computer-readable medium may include any tangible device capable of storing instructions that are executed by a suitable device. As a result, a computer-readable medium having instructions stored thereon comprises an article of manufacture that includes instructions that can be executed to create means for performing the operations specified in the flowchart or block diagram. Examples of computer-readable media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of computer-readable media may include floppy disks, diskettes, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), electrically erasable programmable read-only memories (EEPROMs), static random access memories (SRAMs), compact disk read-only memories (CD-ROMs), digital versatile disks (DVDs), Blu-ray (RTM) disks, memory sticks, integrated circuit cards, and the like.

[0124] The computer readable instructions may include either source code or object code written in any combination of one or more programming languages. The source code or object code includes conventional procedural programming languages. The conventional procedural programming languages ​​may be assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state setting data, or object oriented programming languages ​​such as Smalltalk®, JAVA®, C++, etc., and the “C” programming language or similar programming languages. The computer readable instructions may be provided to a processor or programmable circuitry of a programmable data processing apparatus locally or over a wide area network (WAN) such as a local area network (LAN), the Internet, etc. The processor or programmable circuitry may execute the computer readable instructions to create means for performing the operations specified in the flowcharts or block diagrams.

[0125] Here, the computer may be a computer such as a PC (personal computer), a tablet computer, a smartphone, a workstation, a server computer, or a general-purpose computer, or may be a computer system in which multiple computers are connected. Such a computer system in which multiple computers are connected is also called a distributed computing system, and is a computer in the broad sense. In a distributed computing system, each of the multiple computers executes a part of a program, and the multiple computers collectively execute a program by transferring data during program execution between the computers as necessary.

[0126] Examples of processors include computer processors, central processing units (CPUs), processing units, microprocessors, digital signal processors, controllers, microcontrollers, etc. A computer may have one processor or multiple processors. In a multiprocessor system with multiple processors, each processor executes a part of a program, and the multiple processors collectively execute a program by passing data during program execution between the processors as necessary. For example, in executing multitasks, each of the multiple processors may execute a part of each task in small chunks by switching tasks for each time slice. In this case, which part of a program each processor executes changes dynamically. Also, which part of a program each of the multiple processors executes may be statically determined by programming that takes the multiprocessor into consideration.

[0127] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0128] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and may be realized in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is explained using "first," "next," etc. for convenience, it does not mean that it is essential to perform the process in this order. [Explanation of symbols]

[0129] 10 Unmanned aerial vehicle (UAV) 20 UAV body 30 Imaging device 32 Memory 36 Communication Interface 40 Promotion Department 41 GPS receiver 42 Inertial Measurement Unit 43 Magnetic Compass 44 Barometric altimeter 45 Temperature Sensor 46 Humidity Sensor 50 Gimbal 60 Imaging Device 70 Gas Sensor 72 Intake port 80 Anemometer 100 Control section 200 Pipeline 300 Remote Control Device 301 Transmitter 310 Control section 312 Movement control section 314 Acquisition Department 316 Detection Unit 318 Reception 320 Calibration Section 322 Anomaly detection unit 324 Correction Section 326 Distribution generator 330 Memory 340 Communication Interface 1200 Computer 1210 Host Controller 1212 CPU 1214 RAM 1220 Input / Output Controller 1222 Communication Interface 1230 ROM

Claims

1. a movement control unit that controls the movement of a moving object having a gas sensor mounted thereon; an acquisition unit that acquires a measurement result of the target gas measured by the gas sensor while the moving object is moving within a target area and a response time from when the gas sensor starts measurement until when the gas sensor outputs the measurement result; a detection unit that detects a leak of the target gas in the target area based on the measurement result and the response time, and identifies a gas leak location.

2. The acquisition unit further acquires location information of the moving object when the measurement result is acquired from the gas sensor, The gas leak detection device according to claim 1 , wherein the detection unit identifies a gas leak point where a leak of the target gas has been detected within the target area, based further on the position information.

3. The acquisition unit further acquires speed information of the moving object when the measurement result is acquired from the gas sensor, The gas leak detection device according to claim 1 , wherein the detection unit identifies the gas leak point further based on the speed information.

4. when there is a gas leak candidate area in which the gas concentration of the target gas based on the measurement result measured by the gas sensor while the moving body is moving at a first speed satisfies a first condition, the movement control unit controls the movement of the moving body to move through the gas leak candidate area at a second speed slower than the first speed, or to stop in the gas leak candidate area; the acquisition unit acquires additional measurement results of the target gas measured by the gas sensor while the moving body moves through the gas leak candidate area at the second speed or is stopped in the gas leak candidate area, The gas leak detection device according to claim 1 , wherein the detection unit identifies the gas leak candidate area as the gas leak point when the gas concentration of the target gas based on the additional measurement result satisfies a second condition.

5. When a gas leak candidate area exists in which the gas concentration of the target gas based on the measurement result measured by the gas sensor while the moving body is moving through the target area at a first speed while maintaining a first altitude, the movement control unit controls the movement of the moving body so that the moving body moves through the gas leak candidate area at a second speed slower than the first speed while maintaining a second altitude different from the first altitude, or so that the moving body stops in the gas leak candidate area while maintaining the second altitude, the acquisition unit acquires additional measurement results of the target gas measured by the gas sensor while the moving body moves through the gas leak candidate area at the second speed while maintaining the second altitude, or while the moving body is parked in the gas leak candidate area while maintaining the second altitude, The gas leak detection device according to claim 1 , wherein the detection unit identifies the gas leak candidate area as the gas leak point when the gas concentration of the target gas based on the additional measurement result satisfies a second condition.

6. the movement control unit controls the movement of the moving object so that the moving object moves through the target area a plurality of times; The gas leak detection device according to claim 1 , wherein the detection unit detects a leak of the target gas for each area based on a gas concentration of the target gas based on the measurement result for each area within the target area.

7. The gas leak detection device according to claim 5 , wherein the detection unit detects a leak of the target gas for each area based on an average value of the gas concentration of the target gas in each area based on the measurement result for each area within the target area.

8. 2. The gas leak detection device according to claim 1, wherein the detection unit detects a leak of the target gas based on a deviation of the gas concentration of the target gas based on the measurement results measured by the gas sensor while the moving body is moving, and the deviation is calculated based on the degree of deviation of the gas concentration data of the target gas from a statistical average.

9. A reception unit for receiving a spatial resolution of the gas leak detection is further provided. The gas leak detection device according to claim 1 , wherein the movement control unit controls the movement of the moving body so that the moving body moves at a speed based on the spatial resolution.

10. The acquisition unit further acquires a measurement result of the target gas measured by the gas sensor while the moving object is moving outside the target area, The gas leak detection device includes: The gas leak detection device according to claim 1 , further comprising a calibration unit that calibrates the gas sensor based on the measurement result outside the target area. 。

11. 2. The gas leak detection device according to claim 1, further comprising a correction unit that corrects an error in a measurement result of the target gas measured by the gas sensor due to noise generated in association with driving of a driving source of the moving body, with a correction amount according to a speed of the moving body.

12. The moving body further includes a wind vane and anemometer; 2. The gas leak detection device according to claim 1, wherein the movement control unit controls the movement of the moving body so that the moving body moves in a direction from downwind to upwind in the target area based on a measurement result of the anemometer.

13. A gas leak detection device according to any one of claims 1 to 12; a moving body having a drive source controlled by the gas leak detection device and the gas sensor; A gas leak detection system comprising:

14. The gas leak detection system according to claim 13 , wherein the gas sensor is provided on a ceiling surface of a main body of the moving object.

15. 15. The gas leak detection system according to claim 14, wherein the target gas inlet of the gas sensor is provided on the ceiling surface so as to face a front side when the movable body moves forward.

16. 15. The gas leak detection system according to claim 14, wherein the target gas inlet of the gas sensor is provided on the ceiling surface so as to face the ceiling surface when the moving body moves upward.

17. A plurality of the moving bodies are provided, the plurality of moving bodies measure the gas concentration of the target gas with the gas sensor while moving through at least one of the plurality of target areas included in the total target area; The gas leak detection system comprises: a distribution generating unit that generates gas distribution information of the target gas in the total target area based on the measurement results of the target area provided by each of the plurality of moving objects; The gas leak detection system of claim 13, wherein the distribution generation unit generates the gas distribution information by deriving a baseline corrected distribution of gas concentration so as to minimize a residual between each group of measurement results of the target area provided from each of the moving bodies moving in the target area.

18. each of the plurality of target areas has an overlap area that overlaps with an adjacent target area; The gas leak detection system of claim 17, wherein the distribution generation unit generates the gas distribution information by deriving the gas concentration of the target gas in the overlapping area based on each measurement result provided from each of the moving bodies moving in the overlapping area.

19. Controlling the movement of a moving object having a gas sensor mounted thereon; acquiring a measurement result of the target gas measured by the gas sensor while the moving object is moving in a target area and a response time from when the gas sensor starts measurement until when the gas sensor outputs the measurement result; detecting a leak of the target gas in the target area based on the measurement result and the response time, and identifying a gas leak location.

20. a movement control unit that controls the movement of a moving object having a gas sensor mounted thereon; an acquisition unit that acquires a measurement result of the target gas measured by the gas sensor while the moving object is moving within a target area and a response time from when the gas sensor starts measurement until when the gas sensor outputs the measurement result; a detection unit that detects a leak of the target gas in the target area based on the measurement result and the response time; A program that allows a computer to function.

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