Explosives detection system and explosives detection method

Abstract

To provide an explosives detection system and an explosives detection method capable of detecting TNT explosives buried underground while reducing the risk of personal injury to searchers. [Solution] The explosives detection system 1 is a drone device 2, which includes an unmanned aerial vehicle (drone 6), a tank 7 attached to the drone, a spraying device 8 that sprays a surfactant, a suction device 22 attached to the drone 6 that sucks air, an adsorption column 24 that collects gaseous components generated from TNT explosives, a desorption device 26 that desorbs the components adsorbed in the adsorption column, and a gas chromatograph 28 that detects gaseous components generated from TNT explosives from the components desorbed by the desorption device 26. The drone 6 can be controlled by a control unit 60 to fly to a predetermined position, altitude, and course, and take off and land fully automatically according to a predetermined program.

Description

[Technical Field]

[0001] The present invention relates to an explosives detection system and method. [Background technology]

[0002] As disclosed in Patent Document 1, a method for detecting landmines is known in the past in which workers use metal detectors or the like to search for landmines. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-250451 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology disclosed in Patent Document 1 has the problem that it cannot detect non-metallic landmines. Unfortunately, there are many types of landmines, said to number in the hundreds, and many of them are non-metallic, for example, made of resin. For example, methods have been proposed for detecting such landmines, such as using animals to distinguish between scents, but this method poses the problem of a high risk of human casualties, as humans enter minefields along with animals.

[0005] The present invention has been made to solve such problems, and aims to provide an explosives detection system and explosives detection method that can detect TNT explosives buried underground while reducing the risk of personal injury to searchers. [Means for solving the problem]

[0006] In order to achieve the above object, according to one embodiment of the present invention, an explosives detection system for detecting TNT explosives buried underground is a drone device, the drone device comprising: a drone; a tank provided on the drone; a spraying device for spraying a surfactant; a suction device provided on the drone for sucking air; an adsorption column for collecting gaseous components generated from TNT explosives; a desorption device for desorbing the components adsorbed in the adsorption column; and a gas chromatograph for detecting gaseous components generated from TNT explosives from the components desorbed by the desorption device. According to one embodiment of the present invention configured as described above, components generated from TNT explosives can be sucked in by a suction device, adsorbed into an adsorption column, desorbed from the adsorption column by a desorption device, and detected by a gas chromatograph. This allows the presence of TNT explosives buried underground to be detected regardless of the structure of the device containing the TNT explosives, while reducing the risk of personal injury to the searcher. Furthermore, the presence of TNT explosives buried underground can be detected relatively accurately regardless of the structure of the device containing the TNT explosives. Therefore, even if a landmine is made of resin, if it contains TNT explosives, the TNT explosives themselves can be directly detected, improving the accuracy of landmine detection. Furthermore, for example, in areas where it is suspected that a landmine may be present, it is possible to detect the landmine from a different perspective, that is, whether or not TNT explosives are present, improving the accuracy of landmine detection.

[0007] According to one embodiment of the present invention, the explosives detection method is preferably for detecting TNT explosives buried underground, and comprises a spraying step of spraying a surfactant onto the ground from a spraying device provided on a drone device, a suction step of sucking air using a suction device provided on the drone device, an adsorption step of collecting components resulting from the TNT explosive contained in the sucked air using an adsorption column, a desorption step of desorbing the components adsorbed in the adsorption column using a desorption device, and a detection step of detecting the components resulting from the TNT explosive from the components desorbed by the desorption device using a gas chromatograph. According to one embodiment of the present invention configured as described above, components generated from TNT explosives are aspirated in the aspirating step, adsorbed onto an adsorption column in the adsorption step, desorbed from the adsorption column by a desorption device in the desorption step, and detected by a gas chromatograph in the detecting step. This allows the presence of TNT explosives buried underground to be detected regardless of the structure of the device containing the TNT explosives, while reducing the risk of personal injury to searchers. Furthermore, the presence of TNT explosives buried underground can be detected with relatively high accuracy regardless of the structure of the device containing the TNT explosives. Therefore, even if a mine is made of resin, if it contains TNT explosives, the TNT explosives themselves can be directly detected, improving the accuracy of mine detection. Furthermore, for example, in areas where the presence of a mine is suspected, mines can be detected from a different perspective, determining whether or not TNT explosives are present, improving the accuracy of mine detection. [Effects of the Invention]

[0008] According to the explosives detection system and explosives detection method of the present invention, it is possible to detect TNT explosives buried underground while reducing the risk of personal injury to searchers. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing an outline of a drone device of an explosives detection system according to one embodiment of the present invention spraying a surfactant using a spraying device. FIG. [Figure 2] 1 is a schematic diagram illustrating a drone device of an explosive detection system according to an embodiment of the present invention sucking air using a suction device. FIG. [Figure 3] 1 is a schematic diagram of an explosives detection system according to an embodiment of the present invention; [Figure 4] 1 is a block diagram showing the configuration of a drone device in an explosives detection system according to one embodiment of the present invention. FIG. [Figure 5] 2 is a block diagram showing the configuration of a control unit in the explosives detection system according to the embodiment of the present invention. FIG. [Figure 6]FIG. 1 is a diagram illustrating how components produced by TNT explosives are aspirated and then detected through an adsorption column and a gas chromatograph in an explosives detection system according to an embodiment of the present invention. [Figure 7] FIG. 2 shows a flowchart of an explosives detection method for an explosives detection system according to one embodiment of the present invention. [Figure 8] FIG. 10 is a diagram illustrating a drone device of an explosives detection system according to an embodiment of the present invention moving to a search point and detecting explosives. DETAILED DESCRIPTION OF THE INVENTION

[0010] An explosives detection system 1 according to one embodiment of the present invention will now be described with reference to the accompanying drawings. The embodiments of the present disclosure have been described as examples, and it will be apparent to those skilled in the art that many variations, modifications, and substitutions can be made within the spirit and scope of the present invention. Therefore, the present invention is not limited to the disclosed embodiments, and various variations, modifications, etc. can be made in form and details without departing from the scope of the claims. Furthermore, the components disclosed in the specification can be freely combined.

[0011] 1, an explosives detection system 1 according to one embodiment of the present invention can detect TNT explosives X buried underground. The TNT explosives X buried underground are contained in, for example, land mines M buried underground. The explosives detection system 1 includes a drone device 2. In the following description of one embodiment of the present invention, the sky side of the drone device 2 of the explosives detection system 1 as shown in Figure 1 is referred to as the upper side, and the ground side of the drone device 2 is referred to as the lower side.

[0012] Landmines M are often buried underground near the ground G. Landmines M are often present, for example, at a depth of 1 to 10 cm below the ground surface, or, for example, at a depth of 1 to 5 cm below the ground surface. There are various types of landmines M. Anti-personnel landmines M have diameters ranging from 5 to 20 cm, while anti-tank landmines can be as large as a manhole cover. Destroying landmines M is extremely dangerous and has resulted in many casualties. To minimize casualties, it is important to safely search for, detect, and decommission landmines M. Furthermore, there are many different structures and types of landmines M. Therefore, it can be difficult to detect landmines M based on their structure and type. Furthermore, it can be difficult to determine whether or not a landmine M is present based on a search method for a specific landmine M. In such cases, a second means for determining the presence of landmines M is required.

[0013] The inventors have investigated a technology that significantly improves the determination of whether or not a landmine M is present by directly detecting component X1 of TNT X, which is often used in landmines M. With this technology, landmines M can be detected as long as they contain TNT X, whether they are metal mines using metal components or resin mines using only resin components. TNT explosives (TNT gunpowder) primarily contain trinitrotoluene. TNT explosives volatilize small amounts of component X1, which is generated from TNT X, when they are normally present. Component X1 is, for example, a trace amount of volatilized trinitrotoluene. Furthermore, since the technology can detect objects containing TNT X, not limited to landmines M, it is possible to detect and treat a wide variety of objects that cause human damage, such as landmines and explosives, thereby reducing human casualties. Furthermore, since the technology can detect objects containing TNT, not limited to individual landmines M, it is possible to detect and treat objects that cause human damage, such as structures that explode over a wide area, thereby reducing human casualties. In addition to trinitrotoluene, component X1 may be toluene, which is a raw material for synthesizing TNT, or an intermediate or by-product (for example, 2,4-dinitrotoluene) during the production of TNT.

[0014] The drone device 2 includes a drone 6, a tank 7, a spraying device 8, a suction device 22, an adsorption column 24, a desorption device 26, a gas chromatograph 28, a camera 30 (see Figure 4), an altitude measurement device 32 (see Figure 4), a GPS device 34 (see Figure 4), a communication unit 36 ​​(see Figure 4), and a drone-side control unit 38.

[0015] The drone 6 is an unmanned aerial vehicle, such as a multicopter drone, but may be another type of unmanned aerial vehicle. The drone 6 includes a main body 6a and six arms extending from the main body 6a. Each arm has a rotor 6b and blades (rotating wings) 6c for rotating the blades. The drone 6 is configured to move forward, backward, left, right, and up and down by controlling the rotation speed of each blade 6c. The drone 6 is configured to generate lift sufficient to fly a tank 7, a spraying device 8, and other items. In this embodiment, the drone 6 includes six arms and a blade attached to each arm (a total of six sets of blades). However, other numbers of arms and blades may be used. The drone 6 can fly to a predetermined location, altitude, and course, and take off and land automatically according to a predetermined program, controlled by a control unit 60 (described later). Thus, the drone 6 can travel from a starting point A (see FIG. 8 ) to a predetermined search point D, search for mines M, and return to a return point, such as the same point as the starting point. The drone device 2 may include a manual operation unit 70, and all or part of the controls may be manually operated by the manual operation unit. The drone 6 may be changed to another type of flying object that can fly anywhere, such as a helicopter.

[0016] As shown in FIG. 1 , the tank 7 is provided at the bottom of the drone 6. The tank 7 can store a liquid surfactant 9, for example, a nonionic surfactant. The tank 7 can store, for example, an amount between 3 liters and 20 liters, for example, an amount between 3 liters and 10 liters, for example, an amount between 3 liters and 5 liters. The tank 7 is in communication with a spraying device 8, and the liquid in the tank 7 is supplied to the spraying device 8.

[0017] The spraying device 8 sprays a liquid surfactant 9, for example a non-ionic surfactant. The spraying device 8 is provided at the bottom of the drone 6 and below the tank 7. The spraying device 8 forms a downward-facing water discharge portion. The spraying device 8 is equipped with an electromagnetic valve, and the opening and closing of the flow path (starting and stopping water discharge) can be controlled by the control unit 60. The spraying portion 8a of the spraying device 8 has multiple water discharge holes. The spraying portion 8a of the spraying device 8 protrudes downward and forms part of a curved sphere. The height of the spraying portion 8a is higher than the height of the lower end 23a of the nozzle 23 of the suction device 22. By positioning the spraying portion 8a at a slightly higher position, the range over which the surfactant 9 is sprayed can be made wider than the area suctioned by the suction device. The spraying device 8 is configured to spray the stored liquid at a spray rate per minute ranging from 1,000 milliliters per minute to 1,500 milliliters per minute, for example.

[0018] As the nonionic surfactant, for example, Tween 20 manufactured by Biomedical Sciences Co., Ltd. is used. The amount of Tween 20 to be sprayed is, for example, 100 ml / m 2 up to 200 ml / m 2The amount is within a range of 0.1% to 0.5%. The concentration of Tween 20 is, for example, within a range of 0.1% to 0.5%. The nonionic surfactant can guide component X1 generated from TNT explosives from its underground state as shown in FIG. 1 to the surface of the earth or facilitate collection. Furthermore, when using nonionic surfactants such as Tween 20 manufactured by Biomedical Sciences, a surfactant with relatively low impact on the human body and the environment and extremely high safety can be sprayed, thereby reducing the impact on subsequent land use and the environment. The nonionic surfactant may also be Tween 80 manufactured by Biomedical Sciences. Similarly, when using nonionic surfactants such as Tween 80 manufactured by Biomedical Sciences, a surfactant with relatively low impact on the human body and the environment and extremely high safety can be sprayed, thereby reducing the impact on subsequent land use and the environment. While a nonionic surfactant is preferred for surfactant 9, any surfactant that can easily guide component X1 to the surface of the earth will be effective. Therefore, surfactant 9 may be any other surfactant.

[0019] The suction device 22 is an air suction device capable of sucking air. The suction device 22 is provided on the drone 6. The suction device 22 is connected to the adsorption column 24. The air sucked by the suction device 22 can be sent to the adsorption column 24. The suction device 22 is, for example, an electric micropump, and can deliver (suck) air at a flow rate of 50 ml / min. The suction device 22 is equipped with a nozzle 23 extending downward from the drone 6. The tip of the nozzle 23 is formed to widen in a funnel shape. Therefore, gas guided near the ground G can be sucked toward the suction device 22, as indicated by arrow F1. The length of the nozzle 23 is within a range of 5 cm to 10 cm. As shown in FIG. 1, the distance D2 from the lower end 23a of the nozzle 23 to the foot 6d of the drone 6 is shorter than the distance D1 from the drone 6 to the lower end 23a of the nozzle 23. Since the nozzle 23 of the suction device 22 is located closer to the foot 6d than the main body of the drone 6, it is possible to suck in air at a position closer to the ground G, making it easier to collect components produced from the TNT explosive more efficiently.

[0020] The adsorption column 24 is a device that adsorbs and collects gaseous component X1 generated from TNT explosive X. The component X1 generated from TNT explosive X is, for example, a volatile organic compound (VOC). The adsorption column 24 is provided in the drone 6. The adsorption column 24 is provided with an adsorbent 24a that adsorbs a predetermined gas. For example, the adsorption column 24 uses Tenax TA, which can adsorb gaseous components generated from TNT explosive, as the adsorbent. The adsorbent 24a may be another adsorbent that realizes a solid-phase adsorption method, such as activated carbon or silica gel. The adsorption column 24 is not limited to being one that collects only the gaseous component X1 generated from TNT explosive X, and may also collect other components as long as it can capture the gaseous component generated from TNT explosive.

[0021] The desorber 26 has a function of desorbing at least a portion of the component X1, for example, the TNT explosive component X1, adsorbed in the adsorption column 24. The desorber 26 is provided in the drone 6. The desorber 26 is provided close to the adsorption column 24. The desorber 26 is a device that enables thermal desorption in the adsorption column 24. The desorber 26 has a function of re-volatilizing and dissociating the component X1 adsorbed in the adsorbent 24a of the adsorption column 24, and releasing it from the adsorption column 24. The desorber 26 is configured to be able to heat the adsorbent 24a, for example, for a relatively short period of time.

[0022] 6, the gas chromatograph 28 detects the gas component X1 generated from the TNT explosive from the components desorbed by the desorber 26. The gas chromatograph 28 is provided in the drone 6. The gas chromatograph 28 is configured by, for example, a micro gas chromatograph unit using so-called MEMS technology.

[0023] As shown in Figure 6, the gas chromatograph 28 is provided with a capillary column 29 and a detector 39. The capillary column 29 is configured to separate components in the analysis target in the gas chromatograph 28. The capillary column 29 is configured to separate a predetermined component, for example, component X1, from the inflowing gas. The component separated by the capillary column 29 is detected by the detector 39. The capillary column 29 can also be changed to a packed column.

[0024] The detector 39 detects the component X1 separated by the gas chromatograph 28. The detector 39 is provided on the drone 6. The detector 39 is formed, for example, by a miniature photoionization detector (micro PID) and is configured to be able to analyze the gas component X1 generated from the TNT explosive with relatively high sensitivity, for example, down to the 0.1 ppb level. The detector 39 may also be formed by a mass spectrometer.

[0025] As shown in FIG. 4, the camera 30 is mounted on the main body 6a of the drone 6, and allows the drone 6 to capture and view the surrounding conditions. The camera 30 has the ability to take videos and photos. The camera 30 allows the user to check the conditions around the camera 30 from a remote location, and also capture and record the conditions of the ground at the search point (detection point). The camera 30 is mounted so that it can also capture the conditions directly below the drone 6 in order to check the conditions of the ground G vertically below where the surfactant is sprayed.

[0026] The altitude measurement device 32 is provided on the airframe main body 6a and can measure the altitude H (distance) of the drone 6 relative to the ground G, where there may be buried mines M. The altitude measurement device 32 uses, for example, an ultrasonic altimeter that can measure the height to the ground G. The altitude measurement device 32 may be configured with any one of a barometric pressure measurement sensor that can measure the flight altitude by measuring the air pressure, an ultrasonic sonar that can measure the distance from the drone 6 to the ground G, a laser measurement sensor that can measure the distance from the drone 6 to the ground G, a LIDAR sensor that can measure the distance from the drone 6 to the ground G, or any combination thereof. In this way, the altitude measurement device 32 can measure the altitude H (distance) from the drone 6 to the ground G. For example, the altitude measurement device 32 can measure the altitude (distance) H from the drone 6 to the ground G within a predetermined distance range of 10 cm to 2 m, more preferably within a range of 30 cm to 1 m, and more preferably within a range of 30 cm to 50 cm. After the altitude measurement device 32 recognizes the altitude H (distance) to the ground G, for example, the control unit 60 can issue a command to control the spraying device 8 to spray a surfactant.

[0027] The GPS device 34 is configured to use satellites to identify the current location of the drone 6. The GPS device 34 can acquire location information (such as information on latitude and longitude) of the point where surfactant was sprayed by the spraying device 8 and the point where suction was performed by the suction device 22. Furthermore, the GPS device 34 can recognize the location of the drone 6 and provide the location information necessary for predetermined flight control of the drone 6.

[0028] The communication unit 36 ​​can wirelessly communicate data from the drone device 2 with the control unit 60. For example, the communication unit 36 ​​can transmit information such as the position (coordinates, altitude) of the drone 6 and the location where the surfactant was sprayed by the spraying device 8 to the control unit 60. The control unit 60 is capable of controlling the drone device 2.

[0029] The drone device 2 may be equipped with a manual operation unit 70, a monitor 76, etc. as necessary.

[0030] The drone-side control unit 38 incorporates a CPU 17 and a storage device 19 such as a memory, and controls connected devices to execute predetermined controls based on predetermined control programs stored in the memory, etc. The drone-side control unit 38 is electrically connected to the drone 6, tank 7, spraying device 8, suction device 22, adsorption column 24, desorber 26, gas chromatograph 28, camera 30, altitude measuring device 32, GPS device 34, communication unit 36, etc. These electrical connections may be made via wireless communication, etc.

[0031] The drone-side control unit 38 can execute flight control of the drone 6. The drone-side control unit 38 is configured to perform predetermined functions in cooperation with the control unit 60. The drone-side control unit 38, together with the control unit 60, controls the drone device 2 and the flight of the drone 6. More specifically, the drone-side control unit 38 can control the position (coordinates, altitude) at which the sprayer 8 sprays surfactant, attitude control during spraying, rotation suppression control in the yawing direction, movement between spraying points, etc. In this way, the drone-side control unit 38 can control the flight altitude, flight route, rotation speed and attitude (including left and right roll and yawing in the rotational direction) of the drone 6, and, as necessary, surfactant spraying operation control by the sprayer 8. The drone-side control unit 38 can realize control to make the drone 6 reach a predetermined altitude above the target point (search point) and spray the surfactant by the sprayer 8. The drone-side control unit 38 may be provided integrally with the control unit 60. For example, all or part of the functions of the drone-side control unit 38 may be provided on the control unit side. All or part of the functions of the drone-side control unit 38 may be provided in an information terminal device or the like on the operation unit (not shown) side.

[0032] The drone control unit 38 acquires the coordinates of the target mine M (a location where it is suspected that a mine M exists) from the control unit 60. After recognizing the location of the mine M (the location to be searched), the drone control unit 38 executes the spraying of surfactant by the spraying device 8, thereby improving the accuracy of determining whether explosives are present at the search location (for example, whether a mine M exists) and reducing the risk of human casualties. Note that even if the drone control unit 38 does not know the coordinates or presence of the mine M or TNT explosive, it is possible to have the spraying device spray surfactant onto the ground, detect component X1 produced from the TNT explosive by gas chromatography, and search for the mine M as if screening it.

[0033] The explosives detection system 1 further includes a control unit 60. The control unit 60 is configured to execute control for detecting TNT explosives X buried underground. The control unit 60 is provided, for example, in a computer located remotely from the drone device 2 and the like. As shown in FIG. 3 , the control unit 60 is electrically connected to the drone device 2 and the like via the Internet 3. The control unit 60 may be provided in an electronic device that functions as a computer, such as a smartphone or tablet. The control unit 60 incorporates a CPU 63 and a storage device 65 such as a memory, and controls connected devices based on a predetermined control program recorded in the memory or the like. Thus, the control unit 60 functions as a computer. The electrical connection between the control unit 60 and other devices may be entirely or partially connected via wireless communication, such as infrared communication or other methods. The control unit 60 has a predetermined program for executing a predetermined control function. The control unit 60 may also be composed of multiple devices. The storage device 65 of the control unit 60 stores a predetermined program, but does not necessarily need to store all of the program. Some or all of the program may be stored separately in multiple devices, or may be stored on a server via the Internet. For example, the drone-side control unit 38 mounted on the drone device 2 may be configured to execute some or all of the control functions. The control unit 60 includes an output device 62 such as a monitor and an input device 64 that can be operated to input data, and is capable of setting various modes, etc.

[0034] 5, the control unit 60 has a spraying mode 71 that causes the spraying device 8 of the drone device 2 to spray a surfactant, for example, a nonionic surfactant. The control unit 60 has a program that can execute the spraying mode 71. The control unit 60 has a suction mode 72 that causes the suction device 22 of the drone device 2 to suck in air. The control unit 60 has a program that can execute the suction mode 72. The control unit 60 has an adsorption mode 73 for collecting the gas component X1 generated from the TNT explosive by the adsorption column 24. The control unit 60 has a program capable of executing the adsorption mode 73. The control unit 60 has a desorption mode 74 in which the gas components adsorbed by the adsorption column 24 are desorbed by the desorber 26. The control unit 60 has a program capable of executing the desorption mode 74. The control unit 60 has a detection mode 75 for detecting a gas component X1 resulting from TNT explosive from the gas components desorbed in the desorption mode 74 using the gas chromatograph 28. The control unit 60 has a program capable of executing the detection mode 75.

[0035] Next, as shown in FIG. 7, a series of operations for detecting TNT explosives buried underground by the explosives detection system 1 will be described. As shown in FIG. 7, in preparation step S1 of the explosives detection system 1, the drone device 2, the control unit 60, and the like of the explosives detection system 1 are prepared. The drone device 2 is installed at the starting point A (see FIG. 8). The spraying device 8, the suction device 22, the adsorption column 24, the desorber 26, and the gas chromatograph 28 are also prepared for use. The control unit 60 also prepares or acquires flight data for the drone device 2 (e.g., coordinates of the search point (see FIG. 7), flight route, flight altitude data (detection altitude data) relative to the ground G at the coordinates of the search point D, etc.). The control unit 60 receives, for example, coordinates indicating a predetermined search area D. The coordinates indicating the predetermined search area D may be set, for example, as coordinates where the presence of a mine M is suspected using another mine M detection method, but the presence of the mine M is to be confirmed by another method as a second check, particularly, as coordinates where the presence or absence of the mine M is to be confirmed by another method. After step S1 is completed, the control unit 60 proceeds to S2.

[0036] In step S2, the control unit 60 flies the drone 2 from the starting point A to above the search point D, as shown in FIG. 8 . Search point D is the location where the TNT explosive detection process is performed. The control unit 60 stops the operation of the spraying device while the drone 2 is moving. The control unit 60 stops the operation of the suction device 22 while the drone 2 is moving. In step S2, the control unit 60 executes a spraying step S2 in which, using the spraying mode 71, the spraying device 8 of the drone 2 sprays a surfactant 9 into a predetermined search area D below the drone. The predetermined search area D is, for example, a square area measuring 30 cm in length and 30 cm in width. The nonionic surfactant sprayed by the spraying device 8 penetrates into the ground and helps guide or promote the movement of gas component X1 generated from the TNT explosive X underground near the surface of the ground G. The nonionic surfactant can increase the concentration of volatilized TNT gas. Therefore, the gas component X1 generated from the TNT explosive is likely to collect near the surface of the ground G. When the control unit 60 has finished spraying by the drone device 2, it returns the drone device 2 to the starting point A, where it lands and stops. When step S2 is completed, the control unit 60 proceeds to S3. After the spraying in step S2, the control unit 60 waits an interval of about 5 to 20 minutes before executing step S3.

[0037] In step S3, the control unit 60 executes the suction mode 72, and executes a suction step S3 in which air is sucked in by the suction device 22 provided in the drone device 2. In the suction step S3, the control unit 60 positions the drone device 2 at a relatively low altitude such that the lower end 23a of the nozzle 23 approaches the ground G, for example, at an altitude of 0.15 m above the ground. The control unit 60 executes the suction mode 72, and causes the suction device 22 to suck in air at the search point D, as indicated by the arrow F1 (see FIGS. 2 and 6). At this time, due to the influence of the nonionic surfactant, component X1 generated from the TNT explosive is present near the ground surface, and component X1 is sucked in along with the air due to the air suction. Component X1 generated from the TNT explosive is illustrated, for example, in FIG. 6 by a filled-in black triangle. The air sucked in by the suction device 22 is sent from the suction device 22 to the adsorption column 24, as indicated by the arrow F2 in FIG. 6. In the suction step S3, the drone device 2 is hovering at a predetermined altitude H2 for air suction. The predetermined altitude H2 is lower than the altitude H1 during spraying. When step S3 is completed, the control unit 60 proceeds to S4.

[0038] In step S4, the control unit 60 executes the adsorption mode 73, thereby executing an adsorption step S4 in which component X1, which is generated from TNT explosive and contained in the sucked air, is collected by the adsorption column 24. As shown by arrow F2 in FIG. 6, the sucked air is sent from the suction device 22 to the adsorption column 24, and component X1 is adsorbed by the adsorbent 24a, for example, Tenax TA, in the adsorption column 24. For example, the control unit 60 may end S4 and proceed to S5 when it determines that a certain amount of component X1 has been collected by the adsorption column 24. When step S4 ends, the control unit 60 proceeds to S5.

[0039] In step S5, the control unit 60 executes the desorption mode 74, which executes a desorption step S5 in which the component X1 adsorbed by the adsorption column 24 is desorbed by the desorber 26. The gas component X1 adsorbed by the adsorption column 24 is desorbed in one go by the desorber 26, and as shown by arrow F3, the gas component X1 is concentrated and sent to the gas chromatograph 28, thereby improving the accuracy of subsequent separation and detection. Therefore, the component X1 is sent to the gas chromatograph 28 together with air. The desorber 26 is, for example, a desorber that instantaneously heats and desorbs the adsorption column 24. In S5, the drone device 2 may be in the same position as S3, or may be in a moving position returning to the starting position A, or may be at the starting position A. When step S5 is completed, the control unit 60 proceeds to S6.

[0040] In step S6, the control unit 60 executes the detection mode 75, which executes a detection step S6 in which the gas chromatograph 28 detects component X1 resulting from TNT explosive from the components desorbed by the desorber 26. As shown in FIG. 6, component X1 desorbed by the desorber 26 is input to the gas chromatograph 28, and a predetermined component X1, for example, is separated in the capillary column 29. Then, as shown in FIG. 6, the detector 39 detects the separated component X1. In FIG. 6, an example waveform of the components detected by the detector 39 is illustrated as 32a. The predetermined component X1 separated by the gas chromatograph 28 can be detected by the detector 39 with relatively high sensitivity, for example, at a sensitivity of 0.1 ppb. In S6, the drone 2 may be located in a position similar to S3, S4, etc., or may be located at the starting position A while moving back to the starting position A. Data obtained by the gas chromatograph 28 is sent to the control unit 60. The detection result of the component X1 may be analyzed at any timing, separate from the flight timing, by the control unit 60. When step S6 is completed, the control unit 60 proceeds to END.

[0041] Examples of an embodiment of the present invention may be provided in each aspect as described below.

[0042] (1) An explosives detection system for detecting TNT explosives buried underground, comprising a drone device, the drone device comprising: a drone; a tank attached to the drone; a spraying device for spraying a surfactant; a suction device attached to the drone for sucking air; an adsorption column for collecting gaseous components generated from the TNT explosive; a desorption device for desorbing the components adsorbed in the adsorption column; and a gas chromatograph for detecting gaseous components generated from the TNT explosive from the components desorbed by the desorption device.

[0043] (2) The explosive detection system described in (1), wherein the surfactant is a nonionic surfactant.

[0044] (3) The explosive detection system described in (1), wherein the suction device has a nozzle extending downward from the drone, and the distance from the lower end of the nozzle to the foot of the drone is shorter than the distance from the drone to the lower end of the nozzle.

[0045] (4) An explosive detection system as described in (1), wherein the height of the spraying portion of the spraying device is higher than the height of the lower end of the nozzle of the suction device.

[0046] (5) An explosives detection method for detecting TNT explosives buried underground, comprising: a spraying step of spraying a surfactant onto the ground from a spraying device provided on a drone device; a suction step of sucking air using a suction device provided on the drone device; an adsorption step of collecting components resulting from the TNT explosive contained in the sucked air using an adsorption column; a desorption step of desorbing the components adsorbed in the adsorption column using a desorption device; and a detection step of detecting the components resulting from the TNT explosive from the components desorbed by the desorption device using a gas chromatograph.

[0047] The embodiments for carrying out the present invention are not limited to the above, and other modifications may be applied. Various alternative embodiments and examples will be apparent to those skilled in the art based on the disclosed technology. In this embodiment, the spraying device 8 sprays the surfactant 9 when the drone 6 of the drone device 2 is located at a predetermined altitude H, for example, 30 cm above the ground G. However, as a modified example, the spraying device 8 may spray the surfactant 9 when the drone 6 of the drone device 2 lands on the ground G. The foot 6d of the drone 6 may be formed in a flat or rectangular frame shape. By forming the foot 6d of the drone 6 so that pressure is less likely to concentrate on a specific point on the ground, the possibility of the mine M being activated when the drone 6 lands can be reduced. Furthermore, by having the spraying device 8 spray the surfactant 9 when the drone 6 lands, the amount of surfactant 9 sprayed can be reduced. Furthermore, all steps S3 to S6, such as suction by the suction device 22, may be executed when the drone 6 lands. Although there is a certain risk of landing, the efficiency of suction of the component X1 by the suction device 22 can be improved, thereby improving the detection accuracy of the component X1.

[0048] In yet another variation, the drone 6 of the drone device 2 in this embodiment is equipped with a tank 7, a sprayer 8, a suction device 22, an adsorption column 24, a desorption device 26, and a gas chromatograph 28. Alternatively, a first drone may be equipped with the tank 7 and the sprayer 8, and a second drone separate from the first drone may be equipped with the suction device 22, the adsorption column 24, the desorption device 26, and the gas chromatograph 28. That is, a drone equipped with the sprayer 8 may be configured separately from a drone equipped with the suction device 22, the gas chromatograph 28, and the like. In this case, a spraying step S2 is performed in which the sprayer 8 equipped in the first drone sprays the surfactant 9 onto the ground. Then, a suction step S3, an adsorption step S4, a desorption step S5, a detection step S6, and the like are performed by the suction device 22 and the like equipped in the second drone. [Explanation of symbols]

[0049] 1: Explosives detection system 2: Drone equipment 6: Drone 7: Tank 8: Spraying device 8a: Spreading part 9: Surfactants 22:Suction device 24: Adsorption column 26: Detachable device 28: Gas chromatograph

Claims

1. 1. An explosives detection system for detecting TNT explosives buried underground, comprising: an explosives detection system comprising: a drone device comprising: a drone; a tank attached to the drone for storing a surfactant; a spraying device for spraying the surfactant onto the ground; a suction device attached to the drone for sucking air; an adsorption column for collecting components resulting from TNT explosive contained in the air sucked by the suction device; a desorption device for desorbing the components adsorbed in the adsorption column; and a gas chromatograph for detecting components resulting from TNT explosive from the components desorbed by the desorption device.

2. 10. The explosives detection system of claim 1, wherein the surfactant is a non-ionic surfactant.

3. 2. The explosive detection system of claim 1, wherein the suction device includes a nozzle extending downward from the drone, and the distance from the bottom end of the nozzle to a foot of the drone is shorter than the distance from the drone to the bottom end of the nozzle.

4. 2. The explosive detection system according to claim 1, wherein the height of the spraying portion of the spraying device is higher than the height of a lower end of the nozzle of the suction device.

5. 1. A method for detecting TNT explosives buried underground, comprising: A spraying step of spraying a surfactant onto the ground from a spraying device provided in the drone device; A suction step of sucking air by a suction device provided in the drone device; an adsorption step of collecting components generated from TNT explosives contained in the sucked air using an adsorption column; a desorption step of desorbing the components adsorbed in the adsorption column using a desorption device; and a detection step of detecting components derived from TNT explosive from the components desorbed by the desorber using a gas chromatograph.

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