Arithmetic processing device for identifying location of buried long object using GPR data from array-type ground-penetrating radar device

Abstract

To accurately identify a buried position and an extension direction even when an apex position of a hyperbolic reflection image is not located directly below data acquisition points.SOLUTION: GPR data are obtained by an array-type ground-penetrating radar device on the first, second, and third analysis lines, which extend in different directions and consist of data acquisition points. From a first angle between the first analysis line and the second analysis line and a second angle between the second analysis line and the third analysis line, a vertex position of a hyperbola of the GPR data on the first analysis line, and a first virtual propagation velocity, a second virtual propagation velocity, and a third virtual propagation velocity of the radio wave in the material below the first analysis line, the second analysis line, and the third analysis line are calculated, respectively. An oblique angle between a fourth straight line projected onto the ground from a long object and the first analysis line, an inclination angle between the long object and the ground, a buried depth from a first point located directly above the long object on the first analysis line to the long object directly below, and a position of the first point are calculated to identify the buried position and extension direction of the long object.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to the field of array-type ground penetrating radar that irradiates electromagnetic waves into the ground to scan the ground and detects the reflected waves that bounce back, and particularly relates to a method and system suitable for identifying the position of a long object buried from GPR data acquired using an array-type ground penetrating radar device.

Background Art

[0002] In order not to damage existing buried pipes and power transmission lines during ground excavation work, etc., identifying their positions is strongly desired at construction sites and building sites, etc. In actuality, the buried objects underground may be in different positions compared to the drawings when pipes, etc. were installed, and it is necessary to identify the positions of the buried objects from the ground using a ground penetrating radar in advance.

[0003] When scanning the ground using a ground penetrating radar (GPR), electromagnetic waves are irradiated into the ground, and the reflected waves that bounce back are detected. The data of the reflected waves acquired at this time is hereinafter referred to as GPR data. GPR data is data in which position information regarding the position where the reflected wave was received, the reflection time from when the electromagnetic wave was irradiated until the reflected wave was received, and information on the reflection wave intensity of the reflected wave are respectively associated. When applied as a ground penetrating radar, it is characterized by irradiating electromagnetic waves omnidirectionally or at a wide angle, and an integrated electromagnetic wave transmitter / receiver is often used. In the GPR data obtained using an integrated electromagnetic wave transmitter / receiver, point-like buried objects such as small stones and iron filings, and long buried objects such as pipes, power transmission lines, and steel bars are detected as hyperbolic reflection images. By analyzing this reflection image, the buried position of the point-like buried object or long object can be identified.

[0004] As a technology using such a ground penetrating radar, for example, there is the technology described in Patent Document 1. In Patent Document 1, it discloses a radar body including an electromagnetic wave transmitting unit that transmits electromagnetic waves toward the ground and an electromagnetic wave receiving unit that receives the reflected waves of the transmitted electromagnetic waves, and a method of detecting buried objects buried in the ground based on received wave data and the like of the electromagnetic waves received by the electromagnetic wave receiving unit. Among them, the apex of the arc-shaped reflected waveform appearing in the detection result is taken as the buried position. When the buried object is a point-like or long object parallel to the ground surface, when the ground penetrating radar is located at a point directly above the buried object, the distance to the buried object directly below is the shortest distance between the ground penetrating radar and the buried object, so the position of the buried object can be specified.

[0005] Non-Patent Document 1 describes a technology using a ground penetrating radar. In the radar profile corresponding to the GPR data obtained by the ground penetrating radar, the horizontal axis is the horizontal position of the antenna, and the vertical axis is the reflection wave time which corresponds to the depth, so a pseudo ground vertical cross-sectional view can be obtained and the underground structure can be judged and buried objects can be detected. And since the position of the buried pipe appears at the apex of the hyperbola, it discloses that the position of the buried pipe can be detected.

[0006] Also, Non-Patent Document 2 discloses the CMP (Common Mid Point) coincidence method which is known for elastic waves and ground penetrating radars.

[0007] Non-Patent Document 3 describes the acquisition of underground data by an array type ground penetrating radar device. The array type ground penetrating radar device has a plurality of transmitting antennas and a plurality of receiving antennas, and is a ground penetrating radar device in which they are arranged linearly. By scanning this ground penetrating radar device in a direction perpendicular to the direction in which the plurality of transmitting and receiving antennas are arranged, GPR data for a plurality of survey lines can be acquired.

[0008] The GPR data of the array-type ground penetrating radar device serving as the prior art will be described below. This GPR data is the data at the data acquisition points of the array-type ground penetrating radar device as shown in FIG. 1. As described in Non-Patent Document 3, the array-type ground penetrating radar device corresponds to a linear array in which a plurality of transmitting and receiving antennas are linearly arranged, and by moving this, GPR data at the data acquisition points as shown in FIG. 1 is acquired. The GPR data includes reflected wave data acquired by the transmitting and receiving antennas.

[0009] FIG. 1 is a top view schematically showing the data acquisition points of the array-type ground penetrating radar device. The data acquisition point 101 is a position where the transmitting and receiving antennas mounted on the array-type ground penetrating radar device irradiate electromagnetic waves into the ground and acquire the reflected wave data. The information at the data acquisition point 101 includes information regarding the data acquisition position, information regarding the time from irradiating electromagnetic waves into the ground until reflection, and information regarding the reflected wave intensity.

[0010] The dotted line frame 102 is a projection of a long object directly above (the surface of a predetermined substance such as the ground surface). First, the GPR data in the analysis line, which is a collection of data acquisition points surrounded by the solid line frame 103, will be described. Hereinafter, the linear collection of data acquisition points surrounded by the solid line frame 103 will be referred to as the analysis line. The analysis line is provided so as to cross the dotted line frame 102 obtained by projecting the long object directly above.

[0011] FIG. 2 shows a cross-sectional view of the analysis line shown in the solid line frame 103. Here, it is assumed that the buried object (for example, the long object 202) is parallel to the ground, and the radius of the long object is so small that it can be ignored compared to the burial depth. The x-axis 201 corresponds to the analysis line, and is an axis with an arbitrary point on the analysis line as the origin and the direction indicated by the arrow of the x-axis 201 as the positive direction. The point 200 indicates the origin. x = x i and x = x 0 represent the positions of the data acquisition points on the analysis line. The point where x = x 0 is the position of the data acquisition point (directly above point) on the x-axis 201 located directly above the long object, and x = x iis the position of any other data acquisition point on the x-axis 201. Also, the time it takes for the electromagnetic wave irradiated from the position x = x 0 to reach the long object is represented by t 0 and the time it takes for the electromagnetic wave irradiated from the position x = x i to reach the long object is represented by t i . At this time, if the true propagation speed of the electromagnetic wave in the ground is represented by v, the distance from the position x = x 0 to the long object 202 is equal to vt 0 and the distance from the position x = x i to the long object 202 is equal to vt i . Therefore, the following (Equation 1) holds by the Pythagorean theorem.

[0012]

Equation

[0013] Solving (Equation 1) for t i yields the left term of (Equation 2). Here, the effective propagation speed v of the electromagnetic wave in the ground can be expressed using the speed of light c 0 and the relative permittivity ε r of the ground as v = c 0 / √(ε r ) and thus can be converted to the right term of (Equation 2).

[0014]

Equation

[0015] Next, a method for calculating the propagation speed v of the electromagnetic wave in (Equation 2) based on GPR data will be described. In this method, first, Kirchhoff migration processing is performed on the acquired radar image to obtain the propagation speed of the electromagnetic wave at which the hyperbola converges to a point. The Kirchhoff migration processing will be described with reference to FIGS. 3A and 3B.

[0016] FIG. 3A and FIG. 3B are schematic diagrams of an example of a radar image. The x-axis 301 in FIGS. 3A and 3B corresponds to the x-axis 201, and the y-axis 302 represents the arrival time t of the electromagnetic wave from the ground. The radar image is composed of a plurality of pixels 303 arranged in a matrix. As shown in FIG. 3A, each pixel 303 is associated with an x-coordinate and an arrival time t. For example, pixel 304 is a pixel corresponding to t = t i , x = x i . When the data acquisition position is x i and the arrival time is t i , the amplitude of the reflected wave is represented by a value corresponding to the luminance of pixel 303, and the radar image is obtained by performing such processing on all pixels.

[0017] As shown in FIG. 3B, when the relative permittivity ε r in the ground or the propagation speed v of the electromagnetic wave is determined in (Equation 2) (x i , t i ), a hyperbola 305 with (x i , t i ) as the vertex is obtained. The process of setting the average luminance of each pixel on the hyperbola 305 as the luminance of pixel 304 at (x i , t i ) in the processed image of the same size is Kirchhoff migration processing. This Kirchhoff migration processing is the same as the CMP stacking method described in Non-Patent Document 2.

[0018] For example, the case where Kirchhoff migration processing is performed in the range of x = x i ± d centered on x = x i will be described. In this case, the average luminance of all pixels on the hyperbola 305 between the pixel 306 corresponding to x = x i - d and the pixel 307 corresponding to x = x i + d is calculated, and it is set as the luminance of pixel 304 at (x i , t i ) in the image after Kirchhoff migration. Performing this process on all pixels is Kirchhoff migration processing. Here, as a selectable value for d, although it depends on the resolution, for example, a value corresponding to several tens to several hundreds of pixels is assumed.

[0019] By performing the Kirchhoff migration process described above, the propagation velocity v of electromagnetic waves or the relative permittivity ε of the ground r is appropriately selected so that the hyperbola 305 converges to a point. An example thereof is shown in FIGS. 4A and 4B.

[0020] FIG. 4A is an example of a radar image before performing the Kirchhoff migration process, and FIG. 4B is an example of an image after performing the Kirchhoff migration process.

[0021] As shown in the frame 401 of FIG. 4A, a hyperbola appears in the radar image before performing the Kirchhoff migration process. On the other hand, as shown in the frame 402 of FIG. 4B, when the Kirchhoff migration process is performed, the hyperbola converges to a substantially point-like shape. By performing the Kirchhoff migration process and finding the point where the hyperbola converges to a substantially point-like shape, an appropriate propagation velocity v of electromagnetic waves or the relative permittivity ε of the ground r can be specified.

[0022] Here, when the extending direction of the buried long object 202 is parallel to the ground, the distance from the radar device to the reflection point of the long object is minimized when the radar device is located directly above the long object, and the vertex of the hyperbola corresponds to the buried position. In FIG. 3(B), the pixel 304 corresponds to the vertex position of the hyperbola, x = x i is the position of the point directly above the long object, and t = t i corresponds to the time for the electromagnetic wave to reach the reflection point of the long object directly below from the ground. Therefore, if the propagation velocity v of the electromagnetic wave in the ground can be specified by the above Kirchhoff migration process, it can be seen that there is a long object at a depth of vt i from the position of x = x i .

[0023] However, when the one-dimensional long object is not parallel to the ground, as shown in FIG. 5, even at the position directly above the long object, the reflection point is not located directly below the data acquisition point. The analysis line 501 is the analysis line extracted from the data acquisition point in FIG. 1. The straight line 503 represents the long object that is not parallel to the ground as a straight line, and the straight line 502 is the straight line obtained by projecting the straight line 503 onto the ground directly above it. The plane containing the analysis line 501 and the straight line 502 corresponds to the surface (ground).

[0024] The dashed triangular prism 504 represents the positional relationship among the analysis line 501, the straight line 502, and the straight line 503. The data acquisition point 507 is the data acquisition point located at the intersection of the analysis line 501 and the straight line 502, the point 505 is the point on the straight line 503 directly below the data acquisition point 507, and the point 506 is the foot of the perpendicular dropped from the data acquisition point 507 to the straight line 503.

[0025] When the straight line 503 corresponding to the long object is parallel to the ground, the point 506 coincides with the point 505, and the reflection point of the electromagnetic wave at the position of the data acquisition point 507 is the point 505. However, when the straight line 503 is not parallel to the ground, since the electromagnetic wave is reflected perpendicular to the straight line 503, it can be seen that the reflection point is the point 506 and is not located directly below the radar device. Therefore, an error occurs in the propagation distance and the buried depth calculated from the arrival time of the electromagnetic wave at the vertex position of the hyperbola.

Prior Art Documents

Patent Documents

[0026]

Patent Document 1

Non-Patent Documents

[0027]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0028] In GPR data, the conventional method of identifying the position of a buried long object from the vertex position in a hyperbolic reflection image is effective when the long object is parallel to the ground. However, when the buried long object is not parallel to the ground, the vertex position in the hyperbolic reflection image is not located directly below the data acquisition point, so there is a deviation between the vertex position and the buried position of the long object. Therefore, as in Patent Document 1 and Non-Patent Document 1, if the vertex position of the hyperbolic reflection image is taken as the buried position of the long object, when the long object is not parallel to the ground, an error will occur compared with the actual buried position, making it difficult to estimate the extension direction of the long object.

Means for Solving the Problems

[0029] This application includes a plurality of means for solving at least a part of the above problems. For example, it is as follows. An arithmetic processing device according to one aspect of the present invention for solving the above problems specifies the position of a long object embedded in a substance from GPR data acquired by an array-type ground penetrating radar device that can move along the surface of the substance while irradiating electromagnetic waves inside the substance, using the arithmetic processing device. The GPR data is data in which position information regarding the position where the reflected wave is received, the reflection time from when the electromagnetic wave is irradiated until the reflected wave is received, and information on the reflected wave intensity are respectively associated. The arithmetic processing device is composed of a virtual propagation speed analysis unit, an obliqueness / tilt angle calculation unit, an embedding depth calculation unit, and an above-embedded object straight-up point position calculation unit. First, GPR data corresponding to a first analysis line, a second analysis line, and a third analysis line, which have different extending directions from each other and are straight lines composed of data acquisition points, in the GPR data acquired using the array-type ground penetrating radar device is input to the virtual propagation speed analysis unit. Next, for the input GPR data, the virtual propagation speed analysis unit outputs information on the vertex position of the hyperbola of the GPR data on the first analysis line, and information on the first virtual propagation speed, the second virtual propagation speed, and the third virtual propagation speed of the electromagnetic wave in the substance below the first analysis line, the second analysis line, and the third analysis line. Next, in the obliqueness / tilt angle calculation unit, using the information on the first angle formed by the first analysis line and the second analysis line and the information on the second angle formed by the second analysis line and the third analysis line as inputs, information on the obliqueness angle formed by the fourth straight line obtained by projecting the long object onto the ground and the first analysis line from the first virtual propagation speed, the second virtual propagation speed, and the third virtual propagation speed of the electromagnetic wave, and information on the tilt angle, which is the angle formed by the long object and the ground, are calculated. Next, in the embedding depth calculation unit, from the information on the obliqueness angle formed by the fourth straight line and the first analysis line, the information on the tilt angle formed by the long object and the ground, and the information on the vertex position of the hyperbola of the GPR data on the first analysis line, information on the embedding depth from the straight-up point located directly above the long object on the first analysis line to the long object directly below is calculated.Finally, the position calculation unit directly above the buried object calculates the information on the position of the first point from the information on the oblique intersection angle formed by the fourth straight line and the first analysis line, the information on the inclination angle which is the angle formed by the long object and the ground, the information on the vertex position of the hyperbola of the GPR data on the first analysis line, and the information on the burial depth from the first point directly above the long object on the first analysis line to the long object directly below. As described above, the information on the oblique intersection angle, the inclination angle, the burial depth, and the position of the point directly above the long object for specifying the burial position of the long object is calculated.

Advantages of the Invention

[0030] Even when the buried long object is not parallel to the ground, by analyzing the GPR data of the array type ground penetrating radar device, there is an effect that the position and the extension direction of the buried object can be known. In particular, it is possible to accurately grasp at what inclination the long object is buried in the ground.

[0031] Problems, configurations, and effects other than those described above will be clarified by the description of the following embodiments.

Brief Description of the Drawings

[0032]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Embodiments for Carrying Out the Invention

[0033] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings for explaining the embodiment, the same members are generally denoted by the same reference numerals, and the repeated explanations thereof are omitted as appropriate. Further, in the following embodiments, it goes without saying that the constituent elements (including element steps, etc.) are not necessarily essential unless otherwise explicitly stated or considered to be clearly essential in principle. Further, when it is said that "consisting of A", "composed of A", "having A", or "including A", it goes without saying that other elements are not excluded unless it is explicitly stated that only that element is meant. Similarly, in the following embodiments, when referring to the shape, positional relationship, etc. of the constituent elements, etc., unless otherwise explicitly stated or considered not to be so in principle, those substantially approximating or similar to the shape, etc. are included.

[0034] In the following embodiments, the buried position is specified even when the buried long object is not parallel to the ground from the GPR data on the analysis lines in a plurality of directions.

[0035] [Embodiment 1] In the first embodiment, an arithmetic processing device for specifying the buried position when the buried long object is not parallel to the ground and its processing method will be described.

[0036] FIG. 6A is a diagram showing an example of the inclination angle φ. Specifically, it is a cross-sectional view showing an example of the relationship between the long object and the ground assumed in the present embodiment. The long object 602 is, for example, a pipe or the like, and the angle formed by the extension direction of the long object 602 and the ground 601 is represented by the inclination angle φ.

[0037] FIG. 6B is a diagram showing an example of the skew angle θ. Specifically, it is a perspective view showing an example of the relationship between the long object and the ground assumed in the present embodiment. The x-axis 603 corresponds to the analysis line, is an axis with an arbitrary point as the origin, and the direction indicated by the arrow along the analysis line is taken as positive. In FIG. 6B, the angle formed by the x-axis 603 and the broken line 604 obtained by projecting the extension direction of the long object 602 onto the ground 601 directly above is represented by the skew angle θ.

[0038] FIG. 6C shows an example of the embedding depth z d Specifically, it is a perspective view showing an example of the distance between the x-axis 603 and the long object 602. In FIG. 6C, the x-coordinate of the point 605 on the x-axis 603 corresponding to the position directly above the long object 602 is represented by x 0 , the z-axis 606 is an axis extending vertically downward from the point 605. Also, the point 607 is a point on the long object 602 directly below the point 605. Then, the distance between the point 605 and the point 607 is represented by the embedding depth z d .

[0039] The inclination angle φ, the skew angle θ, and the embedding depth z shown in FIG. 6 d , and x 0 , which is the x-coordinate of the point directly above the long object, can be calculated when the diameter of the long object is small enough to be ignored. In this embodiment, the calculation method will be described.

[0040] In the embodiments according to the present invention, calculating angles such as the inclination angle φ and the skew angle θ includes not only directly obtaining each angle but also calculating information that can identify angles such as cosφ, cosθ, sinφ, sinθ, tanφ, and tanθ.

[0041] First, regarding the assumed reflected image, the formulation of the hyperbola will be described. The equation of the hyperbola shown in the aforementioned (Equation 2) corresponds to the case where the long object 602 is parallel to the ground (φ = 0°), θ = 90°, and z d = vt 0 . Considering the inclination angle φ, the skew angle θ, and the embedding depth z in FIGS. 6A, 6B, and 6C d , the equation of the hyperbola can be expressed as in (Equation 3).

[0042]

Equation

[0043] In (Equation 3), f(θ, φ) is a function consisting of θ and φ, and g(θ, φ, z d ) and h(θ, φ, z d ) are functions of θ, φ, and z dIt is a function consisting of f(θ, φ), g(θ, φ, z d ), h(θ, φ, z d ). When a long object 602 is buried parallel to the ground (φ = 0°), f(θ, φ) = 1 when θ = 90°, g(θ, φ, z d ) = 0, h(θ, φ, z d ) = t 0 2 is satisfied, and it is an approximate function determined so that (Equation 3) coincides with (Equation 2). For example, when the diameter of the long object is negligibly small, f(θ, φ), g(θ, φ, z d ), h(θ, φ, z d ) can be expressed as (Equation 4) to (Equation 6) in order.

[0044]

Number

[0045]

Number

[0046]

Number

[0047] By the above calculation, when the diameter of the long object is negligibly small, t i can be obtained. Next, a method for calculating each parameter from GPR data on analysis lines in a plurality of directions will be described.

[0048] Figure 7 is a diagram showing an example of selecting analysis lines in a plurality of directions from data acquisition points of GPR data. Specifically, it is a diagram showing an example of a method for selecting analysis lines in a plurality of directions from a top view of data acquisition points of GPR data. The solid line frames 701, 702, and 703 represent the data acquisition points constituting the first analysis line, the second analysis line, and the third analysis line, respectively. The positional relationship of such first, second, and third analysis lines is schematically shown in Figure 8.

[0049] FIG. 8 is a diagram showing an example of the positional relationship of the selected analysis lines. Specifically, it is a diagram showing the positional relationship of the analysis lines selected in FIG. 7 in the first embodiment. First, each parameter is calculated from the analysis lines including the first analysis line 801, the second analysis line 802, and the third analysis line 803 from the acquired GPR data. At this time, it is assumed that the first analysis line 801, the second analysis line 802, and the third analysis line 803 have different extending directions from each other and are not parallel.

[0050] The first analysis line 801, the second analysis line 802, and the third analysis line 803 intersect the fourth straight line 604 obtained by projecting the long object 602 onto the ground 601 in a top view. The intersection points of the first analysis line 801, the second analysis line 802, and the third analysis line 803 with the fourth straight line 604 in the top view are the points directly below where the long object 602 is located. Hereinafter, those points are represented by R, S, and T, respectively. The points R, S, and T are the positions corresponding to x = x (the point directly above in FIG. 6C) when the first analysis line 801, the second analysis line 802, and the third analysis line 803 are set on the x-axis. The point R corresponds to the first point located directly above the long object on the first analysis line 801. Here, an arbitrary point on each of the analysis lines of the first analysis line 801, the second analysis line 802, and the third analysis line 803 is taken as the origin, and the axis is taken with the direction of the arrow along each analysis line as the positive direction. 0 (The point directly above in FIG. 6C). The point R corresponds to the first point located directly above the long object on the first analysis line 801. Here, an arbitrary point on each of the analysis lines of the first analysis line 801, the second analysis line 802, and the third analysis line 803 is taken as the origin, and the axis is taken with the direction of the arrow along each analysis line as the positive direction.

[0051] In addition, hereinafter, the first analysis line 801 set on the x-axis is referred to as the x 1 axis. Similarly, the second analysis line 802 set on the x-axis is referred to as the x 2 axis, and the third analysis line 803 set on the x-axis is referred to as the x 3 axis. The position of the point R on the x 1 axis is set as x = x 01 . Also, the intersection point of the first analysis line 801 and the second analysis line 802 is represented by the point V, and the intersection point of the second analysis line 802 and the third analysis line 803 is represented by the point W.

[0052] Furthermore, ∠VRS = θ 1 , ∠VST = θ 2 , ∠WTS = θ 3 , ∠RVS = α 12, ∠SWT = α 23 is represented as θ 1 is an example of the oblique intersection angle formed by the fourth straight line 604 obtained by projecting the long object onto the ground and the first analysis line 801. Generally, θ 1 , θ 2 , θ 3 are different values respectively. Note that α 12 is an example of the first angle, and α 23 is an example of the second angle.

[0053] From the above, by obtaining the parameters of θ 1 , φ, z d1 , x 01 , the underground embedding position and extension direction of the long object 602 can be uniquely specified.

[0054] FIG. 9 is a diagram showing the overall configuration of an arithmetic processing unit 900 that calculates the oblique intersection angle θ 1 , the inclination angle φ, the embedding depth z d1 , and the position x of the point directly above the long object 01 . First, the processing of the arithmetic processing unit 900 in FIG. 9 will be described.

[0055] The arithmetic processing unit 900 includes a virtual propagation speed analysis unit 902, an oblique intersection / inclination angle calculation unit 903, an embedding depth calculation unit 904, and an embedding object directly above point position calculation unit 905. The arithmetic processing unit 900 receives, as inputs, the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, the GPR data 911c of the third analysis line, the information 912a of the first angle, and the information 912b of the second angle, and outputs the information 923a of the oblique intersection angle, the information 923b of the inclination angle, the information 924 of the embedding depth, and the information 925 of the position of the point directly above the embedding object.

[0056] The GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, and the GPR data 911c of the third analysis line are each data in which position information regarding the position where the reflected wave is received, the reflection time from when the electromagnetic wave is irradiated until the reflected wave is received, and information on the reflected wave intensity of the reflected wave are respectively associated. Note that the position information regarding the position where the reflected wave of the GPR data in the first analysis line, the second analysis line, and the third analysis line is received includes information on the relative position regarding the data acquisition point on the same analysis line, and it is not necessary to include information on the positional relationship with the data acquisition points on different analysis lines.

[0057] The information 912a of the first angle, in addition to the value of the first angle α 12 also corresponds to information capable of specifying angles such as cosα 12 , sinα 12 , and tanα 12 . The same applies to the information 912b of the second angle, the information 923a of the skew angle, and the information 923b of the inclination angle. The information 924 of the buried depth corresponds to information on the distance from the first point located directly above the long object to the long object directly below on the first analysis line such as z d1 , and the information 925 of the position of the point directly above the buried object corresponds to the position information of the first point such as x 01 .

[0058] The virtual propagation speed analysis unit 902 calculates information 921 on the vertex position of the hyperbola, information 922a on the first virtual propagation speed, information 922b on the second virtual propagation speed, and information 922c on the third virtual speed using the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, and the GPR data 911c of the third analysis line. The information 921 on the vertex position of the hyperbola corresponds to the information on the vertex position of the hyperbola of the GPR data in the first analysis line. The information 922a on the first virtual propagation speed, the information 922b on the second virtual propagation speed, and the information 922c on the third virtual speed each correspond to information on the speed of the electromagnetic wave. Here, the speed of the electromagnetic wave is obtained by the Kirchhoff migration process in the substance below the first analysis line, the second analysis line, and the third analysis line such that the hyperbola converges to a substantially point shape.

[0059] The skew - inclination angle calculation unit 903 calculates the skew angle information 923a and the inclination angle information 923b using the first - angle information 912a, the second - angle information 912b given as inputs, and the first virtual propagation speed information 922a, the second virtual propagation speed information 922b, and the third virtual speed information 922c generated by the virtual propagation speed analysis unit 902.

[0060] The buried - depth calculation unit 904 calculates the buried - depth information 924 using the hyperbola vertex - position information 921, the skew - angle information 923a, and the inclination - angle information 923b.

[0061] The position - above - buried - object calculation unit 905 calculates the position - above - buried - object information 925 using the hyperbola vertex - position information 921, the skew - angle information 923a, the inclination - angle information 923b, and the buried - depth information 924.

[0062] The processing of the virtual propagation speed analysis unit 902, the skew - inclination angle calculation unit 903, the buried - depth calculation unit 904, and the position - above - buried - object calculation unit 905 will be described in detail below.

[0063] The virtual propagation speed analysis unit 902 identifies the vertex position of the hyperbola using the GPR data of the first analysis line 801, the second analysis line 802, and the third analysis line 803. Since the vertex position of the hyperbola corresponds to the pixel 304 in Figure 3B, the virtual propagation speed analysis unit 902 can identify the vertex position in the GPR data of the first analysis line 801, which is represented here as (x 01 ’, t 01 ’).

[0064] Let the virtual propagation speed of the electromagnetic wave when the hyperbola obtained from the radar image on the first analysis line 801 converges to a point by Kirchhoff migration processing be v 1 ’. Similarly, let the virtual propagation speeds of the electromagnetic waves when the hyperbolas of the respective radar images on the second analysis line 802 and the third analysis line 803 converge to points by Kirchhoff migration processing be v 2 ’ and v 3 ’ respectively.

[0065] The vertex position (x 01 ’, t 01 ’) in the GPR data of the first analysis line 801 corresponds to the vertex position information 921 of the hyperbola and is passed to the buried depth calculation unit 904 and the position calculation unit 905 directly above the buried object. The virtual propagation speeds v 1 ’, v 2 ’, v 3 ’ respectively correspond to the information 922a of the first virtual propagation speed, the information 922b of the second virtual propagation speed, and the information 922c of the third virtual speed, and are passed to the skew / slant angle calculation unit 903.

[0066] The virtual propagation speed analysis unit 902 generates the information required by the buried depth calculation unit 904 and the position calculation unit 905 directly above the buried object by outputting the vertex position in the GPR data. In addition, the virtual propagation speed analysis unit 902 generates the information 922a of the first virtual propagation speed, the information 922b of the second virtual propagation speed, and the information 922c of the third virtual speed required for calculating the skew angle information 923a and the tilt angle information 923b in the skew / slant angle calculation unit 903.

[0067] Next, the processing in the skew / slant angle calculation unit 903 will be described. The skew / slant angle calculation unit 903 receives, as input, information on the first angle and the second angle such as α 12 and α 23 . In addition, the skew / slant angle calculation unit 903 receives, from the virtual propagation speed analysis unit 902, the information 922a of the first virtual propagation speed, the information 922b of the second virtual propagation speed, and the information 922c of the third virtual speed such as the virtual propagation speeds v 1 ’, v 2 ’, v 3 ’. The relationship between the virtual propagation speeds v 1 ’, v 2 ’, v 3 ’ and the effective subsurface propagation speed v of the electromagnetic wave can be expressed as in (Equation 7).

[0068]

Equation

[0069] Also, in the triangles VRS and WTS in FIG. 8, since the sum of the interior angles of a triangle is 180 degrees, (Equation 8) and (Equation 9) hold.

[0070]

Number

[0071]

Number

[0072] Here, α 12 and α 23 are given as the information 912a of the first angle and the information 912b of the second angle in the input. Also, v 1 ’, v 2 ’, v 3 ’ are respectively passed from the virtual propagation speed analysis unit 902 as the information 922a of the first virtual propagation speed, the information 922b of the second virtual propagation speed, and the information 922c of the third virtual speed. Therefore, using the three equations of (Equation 7) and the two equations of (Equation 8) and (Equation 9), the effective underground propagation speed v and φ, θ 1 , θ 2 , θ 3 of the five parameters can be calculated. Note that for the parameter calculation of φ, θ 1 , θ 2 , θ 3 , in addition to directly calculating each angle, it is also assumed that information for specifying angles such as cosφ, cosθ 1 , cosθ 2 , cosθ 3 , sinφ, sinθ 1 , sinθ 2 , sinθ 3 , tanφ, tanθ 1 , tanθ 2 , tanθ 3 etc. can be calculated.

[0073] As described above, the skew / slant angle calculation unit 903 uses mathematical formulas to calculate v, φ, θ 1 , θ2 , θ 3 is calculated. The skew angle θ 1 and the tilt angle φ correspond to the skew angle information 923a and the tilt angle information 923b, and are passed to the buried depth calculation unit 904 and the position calculation unit 905 directly above the buried object, and at the same time, they are also part of the output of the arithmetic processing unit 900.

[0074] The skew / tilt angle calculation unit 903 can calculate the skew angle θ 1 and the tilt angle φ mathematically from the three-direction GPR data, and can obtain the tilt angle and the respective skew angles when the buried long object is not parallel to the ground.

[0075] Next, the process of the buried depth calculation unit 904 calculating the buried depth will be described. The buried depth calculation unit 904 receives, from the virtual propagation speed analysis unit 902, the vertex position information 921 of the vertex position (x 01 ’, t 01 ’) of the hyperbola in the GPR data of the first analysis line 801. Also, from the skew / tilt angle calculation unit 903, it receives the skew angle information 923a such as θ 1 and the tilt angle information 923b such as φ.

[0076] Regarding the vertex position (x 01 ’, t 01 ’) in the GPR data of the first analysis line 801, t 01 ’ can be expressed as in (Equation 10) based on (Equation 3).

[0077]

Equation

[0078] The t 01 ’ in (Equation 10) is known because it is passed from the virtual propagation speed analysis unit 902, and the skew angle θ 1 and the tilt angle φ are passed from the skew / tilt angle calculation unit 903, and thus the buried depth z d1 is calculated. The buried depth z d1This corresponds to the buried depth information 924, and is passed to the point position calculation unit 905 directly above the buried object, and at the same time, it is also part of the output of the arithmetic processing unit 900.

[0079] The buried depth calculation unit 904 can specify the buried depth from the point directly below where the buried long object is located on the analysis line even when the buried long object is not parallel to the ground based on (Equation 3).

[0080] Next, the process of the point position calculation unit 905 directly above the buried object will be described. The point position calculation unit 905 directly above the buried object receives, as input, the vertex position information 921 of the vertex position (x 01 ’, t 01 ’) of the hyperbola in the GPR data of the first analysis line 801 from the virtual propagation velocity analysis unit 902. Also, the point position calculation unit 905 directly above the buried object receives the skew angle information 923a such as θ 1 and the tilt angle information 923b such as φ from the skew / tilt angle calculation unit 903. Furthermore, the point position calculation unit 905 directly above the buried object receives the buried depth information 924 such as the buried depth z d1 from the buried depth calculation unit 904. In the point position calculation unit 905 directly above the buried object, the above x 01 ’ can be expressed as in (Equation 11) based on (Equation 3).

[0081]

Equation

[0082] In (Equation 11), x 01 ’ is from the virtual propagation velocity analysis unit 902, the skew angle θ 1 and the tilt angle φ are from the skew / tilt angle calculation unit 903, and the buried depth z d1 is passed from the buried depth calculation unit 904, so they are known, and the position x 01 directly above the point is calculated. The position x 01 directly above the point corresponds to the information 925 of the position directly above the buried object and is part of the output of the arithmetic processing unit 900.

[0083] The position calculation unit 905 for the point directly above the buried object can identify the point directly above the long object 602 shown in FIG. 6C on the first analysis line. This point directly above corresponds to the position of point R in FIG. 8. Also, the position calculation unit 905 for the point directly above the buried object can identify where the long object 602 is located with respect to each analysis line from the burial depth z d1 calculated by the burial depth calculation unit 904.

[0084] As shown in FIG. 9, the arithmetic processing unit 900 outputs information 923a on the skew angle, information 923b on the tilt angle, burial depth information 924 such as the burial depth z d1 , and information 925 on the position of the point directly above the buried object such as the position x 01 of the point directly above the buried object. Therefore, the underground burial position and extension direction of the long object 602 can be uniquely identified.

[0085] Note that the position on the x 2 axis of point S shown in FIG. 8 is set as x = x 02 , and the distance from point S directly downward to the long object 602 is set as z d2 . When this is done, the parameters of z d2 and x 02 can also be obtained in the same way. Therefore, it is also assumed that the underground burial position and extension direction of the long object can be uniquely identified by calculating the parameters of z d1 and x 01 and z d2 and x 02 and clarifying the positions of two points through which the long object passes.

[0086] FIG. 10 is a diagram showing a computer system which is an example of a hardware configuration capable of realizing the arithmetic processing unit according to the first embodiment. The computer system 1200 reads a program stored in the memory resource 1204 by the processor 1201 in order to perform data generation, transmission, reception, and various other processes, and the processor 1201 executes a process of specifying the embedding position of the long object from the GPR data 1213. Note that the computer system 1200 is a computer such as, for example, a personal computer, a tablet terminal, a smartphone, a server computer, a blade server, and a cloud server, and is a system including at least one or more of these computers. That is, the computer system 1200 also includes a system including, for example, a cloud server and a display computer (for example, a tablet terminal or a smartphone). Further, the computer system 1200 may be a controller that controls or manages some device including the processor 1201 and the memory resource 1204.

[0087] Specifically, as shown in FIG. 10, the computer system 1200 includes one or more processors 1201, one or more memory resources 1204, one or more UI (User Interface) devices 1202, and one or more NI (Network Interface) devices 1203. Note that the computer system 1200 may include components other than these. Further, the processor 1201, the UI device 1202, the NI device 1203, and the memory resource 1204 are interconnected via a bus 1205.

[0088] Processor 1201 is an arithmetic unit that reads various programs stored in memory resource 1204 and executes processing corresponding to each program. Examples of such programs include, for example, an OS (Operating System). Note that processor 1201 is an example of a microprocessor, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an FPGA (Field Programmable Gate Array), a quantum processor, or other semiconductor device capable of executing operations.

[0089] Memory resource 1204 is a storage device that stores a virtual propagation speed analysis program 1209, an obliquity / slant angle calculation program 1210, an embedding depth calculation program 1211, an above-embedded object point calculation program 1212, GPR data 1213, analysis information 1214, and intersection angle data 1215 of analysis lines, and examples thereof are non-volatile memory and / or volatile memory. An example of volatile memory is RAM (Random Access Memory). Examples of non-volatile memory may be rewritable storage media such as flash memory, hard disk, ROM (Read Only Memory), or SSD (Solid State Drive), or may be a USB (Universal Serial Bus) memory, a memory card, and a hard disk. Also, RAM such as MRAM (Magnetoresistive RAM), PRAM (Phase change RAM), and ReRAM (Resistive RAM) may be regarded as non-volatile memory. Note that processor 1201 may perform a service of distributing various programs (for example, virtual propagation speed analysis program 1209, obliquity / slant angle calculation program 1210, embedding depth calculation program 1211, above-embedded object point calculation program 1212) stored in memory resource 1204 to other computers.

[0090] The UI device 1202 is an input device for inputting instructions from a user (which may be an operator) into the computer system 1200 and an output device for outputting information and the like generated by the computer system 1200. Examples of the input device include a pointing device such as a keyboard, a touch panel, a mouse, and a voice input device such as a microphone. Unless otherwise specifically mentioned below, the input and output of information between the computer system 1200 and the user are executed via the UI device 1202. Note that the UI device 1202 may be only an input device or only an output device. Examples of the output device include a display device such as a liquid crystal display, a projector that projects information onto a screen, AR glasses, a printer that prints on paper, a smartphone, a smartwatch, and the like.

[0091] The NI device 1203 is a communication device that performs information communication with an external device. The NI device 1203 performs information communication with, for example, a radar device 1207, which is an array-type underground radar device movable along the surface of a substance via a predetermined communication network 1206 such as the Internet or a LAN (Local Area Network), and underground data 1208 in which GPR data is stored. The underground data 1208 includes GPR data 1213 acquired in advance by an underground radar and is a data storage environment stored on a server that can be accessed via the cloud or online. The GPR data 1213 acquired by the radar device 1207 is stored in the underground data 1208 by wirelessly connecting the radar device 1207, and it is also assumed that the GPR data 1213 stored in the radar device 1207 is stored in a non-volatile memory and then transferred to the underground data 1208 for storage.

[0092] Unless otherwise specifically mentioned below, the information communication between the computer system 1200 (or the processor 1201) and an external device such as the radar device 1207 is executed via the NI device 1203.

[0093] This computer system 1200 executes various programs, namely, a virtual propagation speed analysis program 1209, an obliquity / tilt angle calculation program 1210, an embedding depth calculation program 1211, and an above-buried-object point calculation program 1212, thereby executing the processing of the arithmetic processing unit 900 shown in FIG. 9.

[0094] The GPR data 1213 is the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, and the GPR data 911c of the third analysis line stored in the memory resource 1204. The intersection angle data 1215 of the analysis lines is the information 912a of the first angle and the information 912b of the second angle stored in the memory resource 1204. The GPR data 1213 and the intersection angle data 1215 of the analysis lines are captured from the radar device 1207 and the subsurface data 1208 via the NI device 1203 and the bus 1205. Note that the GPR data 1213 and the intersection angle data 1215 of the analysis lines can also be captured into the memory resource 1204 via the bus 1205 by the user directly inputting or uploading data from the UI device 1202.

[0095] The virtual propagation speed analysis program 1209 causes the processor 1201 to perform the processing of the virtual propagation speed analysis unit 902. Similarly, the obliquity / tilt angle calculation program 1210 causes the processor 1201 to perform the processing of the obliquity / tilt angle calculation unit 903, and the embedding depth calculation program 1211 causes the processor 1201 to perform the processing of the embedding depth calculation unit 904. The above-buried-object point calculation program 1212 causes the processor 1201 to perform the processing of the above-buried-object point position calculation unit 905.

[0096] The GPR data 1213 corresponds to the GPR data from the first analysis line 801 to the third analysis line 803, and the intersection angle data 1215 of the analysis lines corresponds to the first angle and the second angle which are the angles formed by the analysis lines. The GPR data 1213 and the intersection angle data 1215 of the analysis lines include information imported from the radar device 1207 and the subsurface data 1208 via the NI device 1203 and the communication network 1206. The GPR data 1213 corresponds to the GPR data that is taken in as input for analysis by the computer system 1200 among the data stored in the subsurface data 1208. Similarly, the intersection angle data 1215 of the analysis lines also corresponds to the information about the intersection angles of the analysis lines that is necessary as input for the computer system 1200 among the data stored in the subsurface data 1208.

[0097] The analysis information 1214 corresponds to the values of various parameters calculated by executing various programs, namely the virtual propagation speed analysis program 1209, the skew / tilt angle calculation program 1210, the buried depth calculation program 1211, and the calculation program 1212 for the point directly above the buried object. Specifically, the virtual propagation speeds v 1 ’, v 2 ’, v 3 ’, the effective subsurface propagation speed v of the electromagnetic wave, the vertex position (x 01 ’, t 01 ’) in the GPR data, the skew angle θ 1 , the tilt angle φ, the buried depth z d1 , the position x 01 directly above the long object, etc. correspond to such information. Among these information, the information necessary to specify the buried position of the long object is displayed by the UI device 1202.

[0098] Also, by executing various programs, namely the virtual propagation speed analysis program 1209, the skew / tilt angle calculation program 1210, the buried depth calculation program 1211, and the calculation program 1212 for the point directly above the buried object, the parameters θ 1 , φ, z d1 , x 01Since it is calculated, the processor 1201 uses this to display the information of the analysis information 1214 on the UI device 1202. As a result, the user can grasp the situation where the long object is buried.

[0099] When the UI device 1202 is a display device, AR glasses, a smartphone, or a smartwatch, etc., the processor 1201 can display the information of the analysis information 1214 on these devices. Also, when the UI device 1202 is a printer, the processor 1201 prints the information of the analysis information 1214 on paper.

[0100] Instead of the output to the user using the UI device 1202 described above, data necessary for the output to the user may be transmitted to an external processor system via the NI device 1203. Examples of the data include, but are not limited to, the data itself to be output or the data for generating the output data in another processor system. For example, it may be a program or web data in which the process of performing user output in an external processor system is described. For example, it is also conceivable that the radar device 1207 receives the output via the NI device 1203 or the communication network 1206 and displays it on the monitor on the radar device 1207.

[0101] Instead of receiving the input or operation from the user using the UI device 1202 described above, data indicating the user input or operation may be received from an external processor system via the NI device 1203. From another perspective, the meaning of data output to the user may include causing (enabling) another entity other than the computer system 1200 to perform the data output, in addition to the computer system 1200 itself performing it. Also, the meaning of receiving the input or operation from the user may include the computer system 1200 indirectly receiving it, in addition to directly outputting and receiving to / from the user by the UI device 1202 of the computer system 1200.

[0102] In the embodiment described above, even when the long object 602 is not buried parallel to the ground 601, it is possible to obtain the parameters of the obliquity angle, inclination angle, burial depth, and the position of the point directly above the long object of the long object. Thereby, the burial position and the extension direction of the long object can be specified.

[0103] 〔Embodiment 2〕 FIG. 11 is a diagram showing an example of the overall configuration of the arithmetic processing unit 1000 in Embodiment 2. The arithmetic processing unit 1000 is configured to obtain the same output by inputting the position information of each analysis line without inputting the information 912a of the first angle and the information 912b of the second angle with respect to the arithmetic processing unit 900 shown in FIG. 9 of Embodiment 1.

[0104] In addition to the virtual propagation speed analysis unit 902, the obliquity / inclination angle calculation unit 903, the burial depth calculation unit 904, and the position calculation unit 905 of the point directly above the buried object included in the arithmetic processing unit 900, the arithmetic processing unit 1000 includes an analysis line direction vector calculation unit 1002 and an analysis line intersection angle calculation unit 1003.

[0105] The arithmetic processing unit 1000 receives, as inputs, the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, the GPR data 911c of the third analysis line, the position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line, and outputs the obliquity angle information 923a, the inclination angle information 923b, the burial depth information 924, and the position information 925 of the point directly above the buried object.

[0106] The position information 1011a of the first analysis line is information on the position coordinates of the data acquisition points on the first analysis line. The position information 1011b of the second analysis line is information on the position coordinates of the data acquisition points on the second analysis line. The position information 1011c of the third analysis line is information on the position coordinates of the data acquisition points on the third analysis line. The position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line may correspond to, for example, position coordinates obtained by GPS or coordinate information of the data acquisition points on each analysis line in the same coordinate plane, as long as the information can show the positional relationship between the data acquisition points on different analysis lines.

[0107] The analysis line direction vector calculation unit 1002 receives the position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line as inputs, generates the information 1021a of the direction vector of the first analysis line, the information 1021b of the direction vector of the second analysis line, and the information 1021c of the direction vector of the third analysis line, and transfers them to the analysis line intersection angle calculation unit 1003. The information 1021a of the direction vector of the first analysis line, the information 1021b of the direction vector of the second analysis line, and the information 1021c of the direction vector of the third analysis line are information for specifying the directions in which the first analysis line, the second analysis line, and the third analysis line extend on the ground, respectively.

[0108] The analysis line intersection angle calculation unit 1003 calculates the information 912a of the first angle and the information 912b of the second angle using the information 1021a of the direction vector of the first analysis line, the information 1021b of the direction vector of the second analysis line, and the information 1021c of the direction vector of the third analysis line, and transfers them to the skew and tilt angle calculation unit 903.

[0109] Next, the details of the processing in the analysis line direction vector calculation unit 1002 and the analysis line intersection angle calculation unit 1003 will be described with reference to FIG. 12.

[0110] First, the calculation of the direction vectors of the first analysis line and the second analysis line will be described. The analysis lines 1101 and 1102 are not parallel to each other. Let the analysis line 1101 and the analysis line 1102 be the first analysis line and the second analysis line, respectively. Select two points from the data acquisition points that make up the analysis line 1101, and name them point A and point B. Also, select two points from the data acquisition points that make up the analysis line 1102, and name them point C and point D. Here, in addition to random selection, a method of selecting the two points that are farthest apart is assumed. Let the coordinates of point A be (x A , y A ), the coordinates of point B be (x B , y B ), the coordinates of point C be (x C , y C ), and the coordinates of point D be (x D , y D ).

[0111] The analysis line direction vector calculation unit 1002 obtains the direction vector of the analysis line 1101 as (x B - x A , y B - y A ) and the direction vector of the analysis line 1102 as (x D - x C , y D - y C ). (x B - x A , y B - y A ) corresponds to the information 1021a of the direction vector of the first analysis line, and (x D - x C , y D - y C ) corresponds to the information 1021b of the direction vector of the second analysis line. The analysis line direction vector calculation unit 1002 calculates the information 1021c of the direction vector of the third analysis line in the same way. In the analysis line direction vector calculation unit 1002, it is assumed that the direction vector is calculated in this way. In addition, it is also conceivable to calculate the regression line from the coordinates of a plurality of data acquisition points and calculate the direction vector from the slope.

[0112] In the analysis line direction vector calculation unit 1002, the information 1021a of the direction vector of the first analysis line obtained in this way, which is (xB -x A ,y B -y A ), and the information 1021b of the direction vector of the second analysis line (x D -x C ,y D -y C ) are passed to the analysis line intersection angle calculation unit 1003. The analysis line direction vector calculation unit 1002 calculates the information 1021c of the direction vector of the third analysis line in the same manner as the direction vectors of the first and second analysis lines, and passes it to the analysis line intersection angle calculation unit 1003.

[0113] The analysis line intersection angle calculation unit 1003 uses the information 1021a of the direction vector of the first analysis line above (x B -x A ,y B -y A ) and the information 1021b of the direction vector of the second analysis line (x D -x C ,y D -y C ) to calculate the first angle α shown in FIG. 12 12 using (Equation 12). This first angle α 12 corresponds to the information 912a of the first angle shown in FIG. 11. Similarly, the analysis line intersection angle calculation unit 1003 calculates the second angle α, which is the information 912b of the second angle shown in FIG. 11 23 using the information 1021b of the direction vector of the second analysis line and the information 1021c of the direction vector of the third analysis line. The first angle α, which is the information 912a of the first angle calculated in this way 12 and the second angle α, which is the information 912b of the second angle 23 are passed to the skew / slant angle calculation unit 903.

[0114]

Equation

[0115] In the analysis line intersection angle calculation unit 1003, the first angle α shown in FIG. 8 12 , the second angle α 23Therefore, since it is calculated, the processing of the virtual propagation speed analysis unit 902, the skew / slant angle calculation unit 903, the buried depth calculation unit 904, and the position calculation unit 905 of the buried object directly above point of the arithmetic processing unit 1000 can be executed in the same manner as in the first embodiment in combination with the GPR data on the first analysis line, the second analysis line, and the third analysis line.

[0116] The arithmetic processing unit 1000 shown in FIG. 11 can obtain the same output as the arithmetic processing unit 900 shown in FIG. 9 without inputting the information 912a of the first angle and the information 912b of the second angle as long as there is the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, the GPR data 911c of the third analysis line, the position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line.

[0117] FIG. 13 is a diagram showing a computer system which is an example of a hardware configuration capable of realizing the arithmetic processing unit according to the second embodiment. The computer system 1300 is basically the same as the computer system 1200 shown in the first embodiment. Hereinafter, the description will focus on the differences. The memory resource 1304 is a storage device that stores a direction vector calculation program 1301 of the analysis line, an intersection angle calculation program 1302 of the analysis line, a virtual propagation speed analysis program 1209, a skew / slant angle calculation program 1210, a buried depth calculation program 1211, a calculation program 1212 of the point directly above the buried object, the position information 1303 of the analysis line, the GPR data 1213, and the analysis information 1314.

[0118] The position information 1303 of the analysis line is the one in which the position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line are stored in the memory resource 1304, and is fetched from the radar device 1207 and the subsurface data 1208 via the NI device 1203 and the bus 1205. Note that the GPR data 1213 can also be fetched into the memory resource 1304 via the bus 1205 by the user directly inputting or uploading the data from the UI device 1202.

[0119] The analysis line direction vector calculation program 1301 causes the processor 1201 to perform the processing of the analysis line direction vector calculation unit 1002 shown in FIG. 11. Similarly, the analysis line intersection angle calculation program 1302 causes the processor 1201 to perform the processing of the analysis line direction vector calculation unit 1002 shown in FIG. 11. The direction vector calculated by the analysis line direction vector calculation program 1301 and the values of the first angle and the second angle calculated by the analysis line intersection angle calculation program 1302 are stored in the analysis information 1314.

[0120] The analysis information 1314 is the values of various parameters calculated by executing various programs, namely, the analysis line direction vector calculation program 1301, the analysis line intersection angle calculation program 1302, the virtual propagation speed analysis program 1209, the skew / slant angle calculation program 1210, the embedding depth calculation program 1211, and the point directly above the buried object calculation program 1212. Specifically, the analysis information 1314 includes the first angle α 12 and the second angle α 23 , the virtual propagation speeds v 1 ’, v 2 ’, v 3 ’, the true underground propagation speed v of the electromagnetic wave, the vertex position (x 01 ’, t 01 ’) in the GPR data, the skew angles θ 1 , θ 2 , θ 3 , the slant angle φ, the embedding depth z d1 , the position x 01 directly above the long object, etc. Among these pieces of information, the information necessary to specify the embedding position of the long object can be displayed on the UI device 1202.

[0121] This computer system 1300 can execute the processing of the arithmetic processing unit 1000 shown in FIG. 11 by executing various programs, namely, the analysis line direction vector calculation program 1301, the analysis line intersection angle calculation program 1302, the virtual propagation speed analysis program 1209, the skew / slant angle calculation program 1210, the embedding depth calculation program 1211, and the point directly above the buried object calculation program 1212.

[0122] [Embodiment 3] FIG. 14 is a diagram showing an example of the overall configuration of the arithmetic processing system according to the third embodiment. The arithmetic processing system 1400 is basically the same as the arithmetic processing device 900 shown in FIG. 9 of the first embodiment, but there are some differences. The arithmetic processing system 1400 includes a display unit 1401 that can display an output.

[0123] The arithmetic processing system 1400 includes an arithmetic processing device 900 that receives, as inputs, the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, the GPR data 911c of the third analysis line, the information 912a of the first angle, and the information 912b of the second angle, and a display unit 1401. The display unit 1401 displays the information 923a of the skew angle, the information 923b of the tilt angle, the information 924 of the embedding depth, and the information 925 of the position of the point directly above the embedded object output from the arithmetic processing device 900.

[0124] Here, a means for the display unit 1401 to display the skew angle θ 1 , tilt angle φ, embedding depth z d1 , position x of the point directly above the long object 01 of the information output from the arithmetic processing device 900 to the user as the embedding position of the long object will be described.

[0125] FIG. 15 is a diagram showing a display example of the information output in the first and second embodiments. The display screen 1500 shows an example of the display on the display unit 1401. The display screen 1500 displays in 3D the positional relationship between the first analysis line 801, the second analysis line 802, the third analysis line 803, the long object 602 buried underground, the ground 601, and the broken line 604 obtained by projecting the long object 602 onto the ground 601. The broken line 1501 is an extension line of the long object 602, and the angle formed by the broken line 1501 and the broken line 604 is defined as the tilt angle φ. Also, the angle formed by the first analysis line 801 and the broken line 604 is the skew angle θ 1 , the embedding depth directly below the long object 602 at point R is z d1 , and they are respectively shown on the display screen 1500. Also, point O is the origin of the first analysis line 801 and is hidden if necessary according to the setting.

[0126] The display unit 1401 that constitutes the arithmetic processing system 1400 shown in FIG. 14 can be realized, for example, by displaying the display screen 1500 using the UI device 1202 of the computer system 1200 in FIG. 10. Note that the processor 1201 shown in FIG. 10 may display a situation where a long object is actually buried underground on the UI device 1202 in a drawing such as a 2D drawing or a 3D drawing. For example, when the UI device 1202 is a display device, AR glasses, a smartphone, or a smartwatch, etc., the display screen 1500 is displayed on these devices. Also, when the UI device 1202 is a printer, it is possible to print the drawing on paper.

[0127] As described above, according to the arithmetic processing system 1400 described with reference to FIG. 14, based on the result output by the arithmetic processing device 900, the user can visually grasp the situation where the long object is buried.

[0128] 〔Embodiment 4〕 FIG. 16 is a diagram showing an example of the overall configuration of the arithmetic processing system according to the fourth embodiment. The arithmetic processing system 1402 is basically the same as the arithmetic processing device 1000 shown in FIG. 11 of Embodiment 2, but there are some differences. The arithmetic processing system 1402 includes a display unit 1401 that can display an output.

[0129] The arithmetic processing system 1402 includes an arithmetic processing device 1000 that receives, as inputs, the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, the GPR data 911c of the third analysis line, the position information 1011a of the first analysis line, the position information 1011b of the second analysis line, and the position information 1011c of the third analysis line, and a display unit 1401. As described in Embodiment 3, the display unit 1401 displays the skew angle information 923a, the tilt angle information 923b, further, the buried depth information 924, and the information 925 of the position directly above the buried object output from the skew / tilt angle calculation unit 903.

[0130] The display unit 1401 that constitutes the arithmetic processing system 1402 shown in FIG. 16 can be realized by displaying the display screen 1500 shown in FIG. 15 via the UI device 1202 of the computer system 1300 in FIG. 13.

[0131] According to the arithmetic processing system 1402, based on the result output by the arithmetic processing device 1000, the user can visually grasp the situation where the long object is buried.

[0132] 〔Embodiment 5〕 In Embodiment 5, FIG. 17 is a diagram for explaining the operations described in Embodiment 1 step by step. FIG. 17 is a flowchart showing, step by step, an arithmetic processing method for outputting information on the skew angle, tilt angle, buried depth, and position of the point directly above the buried object using GPR data and information on the first angle and second angle.

[0133] First, in the virtual propagation speed analysis step S902, the virtual propagation speed analysis unit 902 generates information on the vertex position of the hyperbola on the first analysis line and information on the virtual propagation speed of each analysis line using the GPR data including the first analysis line, second analysis line, and third analysis line. Here, the virtual propagation speed analysis step S902 corresponds to the processing step in which the virtual propagation speed analysis unit 902 converts the GPR data 911a of the first analysis line, the GPR data 911b of the second analysis line, and the GPR data 911c of the third analysis line into the information 921 on the vertex position of the hyperbola and the information 922a on the first virtual propagation speed, the information 922b on the second virtual propagation speed, and the information 922c on the third virtual speed, as described in FIG. 9 of Example 1.

[0134] Next, in the skew and tilt angle calculation step S903, the skew and tilt angle calculation unit 903 uses the information on the first angle and the second angle given as input, and the information on the virtual propagation speed on each analysis line to generate information on the skew angle formed by the fourth straight line and the first analysis line, and the tilt angle formed by the long object and the ground. As described in FIG. 9 of the first embodiment, the skew and tilt angle calculation step S903 corresponds to the processing step in which the skew and tilt angle calculation unit 903 converts the information 912a on the first angle, the information 912b on the second angle, the information 922a on the first virtual propagation speed, the information 922b on the second virtual propagation speed, and the information 922c on the third virtual speed into the information 923a on the skew angle and the information 923b on the tilt angle.

[0135] Furthermore, in the buried depth calculation step S904, the buried depth calculation unit 904 uses the information on the skew angle, the tilt angle, and the information on the vertex position of the hyperbola of the GPR data on the first analysis line to generate information on the buried depth, which is the distance from the first point located directly above the long object on the first analysis line to the long object directly below. As described in FIG. 9 of the first embodiment, the buried depth calculation step S904 corresponds to the processing step in which the buried depth calculation unit 904 converts the information 921 on the vertex position of the hyperbola, the information 923a on the skew angle, and the information 923b on the tilt angle into the information 924 on the buried depth.

[0136] Then, in the position calculation step S905 of the point directly above the buried object, the position information of the first point located directly above the long object on the first analysis line is generated using the information on the skew angle, the tilt angle, the information on the vertex position of the hyperbola of the GPR data on the first analysis line, and the information on the buried depth. As described in FIG. 9 of the first embodiment, the position calculation step S905 of the point directly above the buried object corresponds to the processing step in which the position calculation unit 905 of the point directly above the buried object converts the information 921 on the vertex position of the hyperbola, the information 923a on the skew angle, the information 923b on the tilt angle, and the information 924 on the buried depth into the information 925 on the position of the point directly above the buried object.

[0137] According to the flow of the arithmetic processing method that outputs information on the skew angle, tilt angle, buried depth, and position of the point directly above the buried object from the GPR data shown in FIG. 17 and the information on the first angle and the second angle, information on the skew angle, tilt angle, buried depth, and position of the point directly above the buried object is output, and the underground burial position and extension direction of the long object 602 can be uniquely specified. Further, even when the long object 602 is not parallel to the ground, analyzing the GPR data of the array type ground penetrating radar device can find the burial position and extension direction of the long object. The effects described in this specification are merely illustrative and not limiting, and there may be other effects.

[0138] The present invention is not limited to the above-described embodiments, and includes various modifications. For example, each of the above-described embodiments has been described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to those having all the components described. Also, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Also, for a part of the configuration of each embodiment, addition, deletion, or replacement with other configurations is possible.

[0139] In addition, each of the above configurations, functions, processing units, processing means, etc. may be realized in hardware by designing a part or all of them, for example, by an integrated circuit. Also, each of the above configurations, functions, etc. may be realized in software by a processor interpreting and executing a program that realizes each function. Information such as a program, determination table, file, etc. for realizing each function can be placed in a memory, a storage device such as an HDD or SSD, or a recording medium such as an IC (Integrated Circuit) card, SD (Secure Digital) card, or DVD (Digital Versatile Disc). Also, control lines and information lines show those considered necessary for explanation, and not necessarily all control lines and information lines are shown on the product. In practice, it may be considered that almost all configurations are interconnected.

Explanation of Reference Numerals

[0140] 101…Data acquisition point, 102…Dotted line frame, 103…Solid line frame, 200…Point, 201…X-axis, 202…Long object, 301…X-axis, 302…Y-axis, 303…Pixel, 304…Pixel, 305…Hyperbola, 306…Pixel, 307…Pixel, 401…Frame, 402…Frame, 501…Analysis line, 502…Straight line, 503…Straight line, 504…Dashed triangular prism, 505…Point, 506…Point, 507…Data acquisition point, 601…Ground, 602…Long object, 603…X-axis, 604…Dashed line, 605…Point, 606…Z-axis, 607…Point, 701…Solid line frame, 702…Solid line frame, 703…Solid line frame, 801…First analysis line, 802…Second analysis line, 803…Third analysis line, 900…Arithmetic processing unit, 902…Virtual propagation speed analysis unit, 903…Oblique intersection and inclination angle calculation unit, 904…Burial depth calculation unit, 905…Position calculation unit of the point directly above the buried object, 911a…GPR data of the first analysis line, 911b…GPR data of the second analysis line, 911c…GPR data of the third analysis line, 912a…Information of the first angle, 912b…Information of the second angle, 921…Information of the vertex position of the hyperbola, 922a…Information of the first virtual propagation speed, 922b…Information of the second virtual propagation speed, 922c…Information of the third virtual propagation speed, 923a…Information of the oblique intersection angle, 923b…Information of the inclination angle, 924…Information of the burial depth, 925…Information of the position of the point directly above the buried object, 1000…Arithmetic processing unit, 1002…Direction vector calculation unit of the analysis line, 1003…Intersection angle calculation unit of the analysis line, 1011a…Position information of the first analysis line, 1011b…Position information of the second analysis line, 1011c…Position information of the third analysis line, 1021a…Information of the direction vector of the first analysis line, 1021b…Information of the direction vector of the second analysis line, 1021c…Information of the direction vector of the third analysis line, 1101…Analysis line, 1102…Analysis line, 1200…Computer system, 1201…Processor, 1202…UI device, 1203…NI device, 1204…Memory resource, 1205…Bus, 1206…Communication network, 1207…Ground penetrating radar device, 1208…Underground data, 1209…Virtual propagation speed analysis program, 1210…Oblique intersection and inclination angle calculation program, 1211…Burial depth calculation program, 1212…Calculation program of the point directly above the buried object, 1213…GPR data, 1214…Analysis information, 1215…Intersection angle data of the analysis line, 1300…Computer system, 1301…Direction vector calculation program of the analysis line,1302…Program for calculating the intersection angle of analysis lines, 1303…Position information of analysis lines, 1304…Memory resources, 1314…Analysis information, 1400…Arithmetic processing system, 1401…Display unit, 1402…Arithmetic processing system, 1500…Display screen, 1501…Dashed line, S902…Virtual propagation speed analysis step, S903…Oblique intersection / inclination angle calculation step, S904…Embedding depth calculation step, S905…Calculation step for the position of the point directly above the embedded object.,

Claims

1. An array-type ground radar device movable along the surface of a substance irradiates the inside of the substance with electromagnetic waves while moving and receives reflected waves obtained thereby, and from GPR data in which position information regarding the position where the reflected waves are received, the reflection time from when the electromagnetic waves are irradiated until the reflected waves are received, and information on the reflected wave intensity of the reflected waves are respectively associated, an arithmetic processing device that specifies the position of a long object in the substance, a virtual propagation speed analysis unit that receives the input of the GPR data corresponding to a first analysis line, a second analysis line, and a third analysis line, which are straight lines composed of data acquisition points and have different extending directions from each other, and outputs, for each of the first analysis line, the second analysis line, and the third analysis line, information on the vertex position of the hyperbola of the GPR data on the first analysis line and information on the propagation speed of the electromagnetic waves in the substance below as information on a first virtual propagation speed, a second virtual propagation speed, and a third virtual propagation speed; an obliqueness / tilt angle calculation unit that receives, as input, information on a first angle formed by the first analysis line and the second analysis line and information on a second angle formed by the second analysis line and the third analysis line, and uses the first virtual propagation speed, the second virtual propagation speed, and the third virtual propagation speed of the electromagnetic waves to calculate information on an obliqueness angle formed by a fourth straight line obtained by projecting the long object onto the surface of the substance and the first analysis line and information on a tilt angle that is the angle formed by the long object and the surface of the substance; a buried depth calculation unit that uses the information on the obliqueness angle formed by the fourth straight line and the first analysis line, the information on the tilt angle formed by the long object and the surface of the substance, and the information on the vertex position of the hyperbola of the GPR data on the first analysis line to calculate information on the buried depth from a first point located directly above the long object on the first analysis line to the long object directly below; a position calculation unit for a point directly above the buried object that calculates the position information of the first point using the information on the obliqueness angle, the information on the tilt angle, the information on the vertex position, and the information on the buried depth; comprising outputting the obliqueness angle, the tilt angle, the buried depth, and information on the position of the point directly above the long object for specifying the buried position of the long object The arithmetic processing device is characterized by the above.

2. The arithmetic processing device according to Claim 1, further Receiving, as an input, the GPR data in analysis lines in a plurality of directions and the position information of the analysis lines, which is the information of the coordinates of the data acquisition points in each of the first analysis line, the second analysis line, and the third analysis line, and calculating the information of the direction vectors of the first analysis line, the second analysis line, and the third analysis line using the information of the data acquisition points constituting each analysis line, an analysis line direction vector calculation unit; A crossing angle calculation unit that calculates the information of the first angle and the second angle using the information of the direction vector of the analysis line and provides it to the skew / slant angle calculation unit; An arithmetic processing device characterized by comprising the above.

3. An arithmetic processing system that acquires the position of a long object embedded in a substance using an array-type ground penetrating radar device that can move along the surface of the substance while irradiating electromagnetic waves inside the substance, and specifies and displays the embedding position of the long object from GPR data in which position information regarding the position where the reflected wave was received, the reflection time from when the electromagnetic wave was irradiated until the reflected wave was received, and the information of the reflected wave intensity of the reflected wave are respectively associated; The arithmetic processing device according to claim 1; A display unit that displays the positional relationship between the analysis line, the surface of the substance, and the embedded long object on the screen using the output information of the skew angle, the tilt angle, the embedding depth, and the position of the point directly above the long object; An arithmetic processing system characterized by having the above.

4. An arithmetic processing system that acquires the position of a long object embedded in a substance using an array-type ground penetrating radar device that can move along the surface of the substance while irradiating electromagnetic waves inside the substance, and specifies and displays the embedding position of the long object from GPR data in which position information regarding the position where the reflected wave was received, the reflection time from when the electromagnetic wave was irradiated until the reflected wave was received, and the information of the reflected wave intensity of the reflected wave are respectively associated; The arithmetic processing device according to claim 2; A display unit that displays the positional relationship between the analysis line, the surface of the substance, and the embedded long object on the screen using the output information of the skew angle, the tilt angle, the embedding depth, and the position of the point directly above the long object; An arithmetic processing system characterized by having the above.

5. An array-type ground radar device capable of moving along the surface of a substance irradiates electromagnetic waves into the substance while moving and receives reflected waves obtained thereby, and from GPR data in which position information regarding the position where the reflected waves are received, the reflection time from when the electromagnetic waves are irradiated until the reflected waves are received, and information on the reflected wave intensity of the reflected waves are respectively associated, a calculation processing method for specifying the position of a long object in the substance by a calculation processing device, the calculation processing device receives input of GPR data corresponding to a first analysis line, a second analysis line, and a third analysis line, which are straight lines composed of data acquisition points and have different extending directions from each other, and outputs, for each of the first analysis line, the second analysis line, and the third analysis line, information on the vertex position of the hyperbola of the GPR data on the first analysis line and information on the propagation speed of the electromagnetic waves in the substance below as information on a first virtual propagation speed, a second virtual propagation speed, and a third virtual propagation speed in a virtual propagation speed analysis step; receives, as input, information on a first angle formed by the first analysis line and the second analysis line and information on a second angle formed by the second analysis line and the third analysis line, and calculates, using the first virtual propagation speed, the second virtual propagation speed, and the third virtual propagation speed of the electromagnetic waves, information on an oblique intersection angle formed by a fourth straight line obtained by projecting the long object onto the surface of the substance and the first analysis line and information on an inclination angle, which is the angle formed by the long object and the surface of the substance, in an oblique intersection / inclination angle calculation step; calculates information on the embedding depth from a first point located directly above the long object on the first analysis line to the long object directly below using the information on the oblique intersection angle formed by the fourth straight line and the first analysis line, the information on the inclination angle, which is the angle formed by the long object and the surface of the substance, and the information on the vertex position of the hyperbola of the GPR data on the first analysis line in an embedding depth calculation step; calculates information on the position of the first point using the information on the oblique intersection angle, the information on the inclination angle, the information on the vertex position, and the information on the embedding depth in an embedded object directly above point position calculation step; and outputs the oblique intersection angle, the inclination angle, the embedding depth, and information on the position of the point directly above the long object for specifying the embedding position of the long object in an output step; characterized by performing the above.

Images