Deep fracture visual photoacoustic magnetic coordination in-situ measuring device and measuring method

Abstract

The application discloses a deep fracture visual photoacoustic magnetic cooperative in-situ measurement device, which comprises a measurement robot placed in a borehole, a cable lowering device placed near a borehole mouth and an upper computer placed outside the borehole. The measurement robot can realize in-situ measurement of fracture networks at different positions in the borehole and has the function of autonomous travel. The cable lowering device mainly realizes depth position sensing of the measurement robot through a depth editor and realizes data communication between the measurement robot and the upper computer. The application further discloses a deep fracture visual photoacoustic magnetic cooperative in-situ measurement method. The application can realize feature area sensing search, autonomous cruise and rapid acquisition of multi-source data, and in combination with a subsequent data processing method, high-precision in-situ measurement and visualization of deep fracture networks can be realized.

Description

Technical Field

[0001] This invention relates to the fields of deep underground engineering rock mass structure fracture network detection and concrete structure defect fracture network detection. Specifically, it relates to a deep fracture visual-optical-magnetic-coordinated in-situ measurement device and a deep fracture visual-optical-magnetic-coordinated in-situ measurement method, which is suitable for morphological observation, depth measurement, deformation monitoring, and three-dimensional visualization of fracture networks in deep structures. It can obtain the spatial morphology and distribution information of deep fracture networks and realize autonomous in-situ inspection, measurement, and visualization of deep fracture networks in vertical and non-vertical boreholes. Background Technology

[0002] The precise three-dimensional measurement of deep fracture networks (such as fractures within rock masses and concrete structures) is a core challenge for geological hazard early warning and engineering safety assessment. Traditional detection methods mainly include borehole acoustic cross-hole CT, contact single-point probe measurement, and fiber optic sensing technology. Borehole acoustic cross-hole CT uses travel-time tomography to invert fracture distribution by arranging acoustic wave transmitting-receiving arrays between boreholes, but its spatial resolution is limited by the borehole spacing (typically >1m) and it cannot characterize millimeter-level fracture aperture. Contact single-point probes can locally measure fracture parameters, but they require manual point-by-point deployment, resulting in low efficiency and difficulty adapting to complex fracture network environments. In recent years, fiber optic sensing technology has indirectly inferred fracture propagation through distributed strain monitoring, but it suffers from response lag and the inability to distinguish between static and dynamic fracture propagation. All of the above methods struggle to achieve in-situ, three-dimensional, millimeter-level precision measurement of deep fractures, hindering the early diagnosis of hidden engineering defects. Existing deep fracture acoustic measurement devices and methods suffer from the following key drawbacks: Insufficient environmental adaptability: Traditional acoustic probes rely on rigid robotic arms for positioning, making them unable to move autonomously within narrow, unstructured fracture cavities, and susceptible to coupling failure due to rock surface roughness; Limited data dimensions: Most devices only collect P-wave arrival time or amplitude parameters, ignoring full waveform information such as S-wave polarization and dispersion, resulting in inversion errors exceeding 30% in fracture attitude (dip angle, strike) and permeability; Weak 3D reconstruction capability: Existing methods mostly rely on interpolation of 2D profile data to generate 3D models, lacking in-situ dynamic tracking of fracture spatial topology, making it difficult to meet the real-time monitoring needs of underground engineering. Furthermore, while existing robot-mounted measurement devices can improve the detection range, their large size (diameter > 15cm) and poor mobility prevent them from penetrating deep into micro-fractures with apertures < 10cm for precise operations, and they lack collaborative control algorithms between acoustic sensors and motion mechanisms.

[0003] To address the aforementioned issues, international research focuses on miniaturized detection devices and full-waveform fusion algorithms. For example, biomimetic crawling robots achieve movement on steeply sloping fracture walls through foot-end adsorption structures, but their drive systems are energy-intensive and lack integrated multi-physics field synchronous measurement capabilities. Multi-frequency acoustic fusion technology improves fracture interface resolution through broadband excitation, but it does not solve the signal distortion problem caused by sensor attitude drift. Current technologies urgently need to overcome the following core challenges: 1. Limitations of single data: Traditional fracture detection relies on single technologies (such as optical images, ultrasound, or ground-penetrating radar), making it difficult to comprehensively characterize the three-dimensional distribution of fractures at the surface, shallow, and deep layers. 2. Difficulties in data fusion: Different detection technologies exhibit significant differences in data resolution, dimensionality (two-dimensional images and three-dimensional point clouds), and physical characteristics (optical, acoustic, electromagnetic waves), lacking effective registration and fusion methods. 3. Model discontinuity: Existing modeling methods cannot correlate the topological relationships between surface and deep fractures, resulting in discontinuous three-dimensional networks. To address the current challenges in in-situ measurement of deep fracture networks, such as limited data simplification, insufficient multi-source data fusion, and the need for improved model network establishment, this invention utilizes mature measurement methods (optical imaging, laser ranging, acoustic scanning, electromagnetic wave detection, etc.) to effectively solve these problems. It simultaneously improves the measurement accuracy of deep fracture networks, enabling three-dimensional reconstruction and visualization of multi-dimensional spatial fracture networks on borehole walls, shallow surfaces, and deep surfaces. This device combines optical imaging, laser ranging, acoustic scanning, electromagnetic wave detection, feature region search, dynamic scanning, autonomous navigation, and precise positioning technologies to achieve collaborative and refined multi-source data detection of multi-dimensional spatial fracture networks on borehole walls, shallow surfaces, and deep surfaces in deep geological boreholes. Finally, by organically pairing and fusing multi-source data within the borehole, high-precision in-situ measurement and visualization of deep fracture networks are achieved. Summary of the Invention

[0004] The purpose of this invention is to address the problems of single measurement data, insufficient fusion of multi-source data, and the need for improvement in model network establishment in in-situ measurement of deep fracture networks. It proposes a combined optical-acoustic-magnetic (OAM) in-situ measurement device and a combined OAM in-situ measurement method for deep fracture networks. This effectively solves the problems of single measurement data, insufficient fusion, and difficult modeling in in-situ measurement of deep fracture networks, while simultaneously improving the measurement accuracy of deep fracture networks. It also enables the three-dimensional reconstruction and visualization of multi-dimensional spatial fracture networks on borehole wall surfaces, shallow surfaces, and deep surfaces.

[0005] To achieve the above objectives, the present invention employs the following technical measures:

[0006] A deep fissure co-optical-magnetic-sound (EMS) in-situ measurement device includes a measurement robot. The measurement robot comprises a front cylinder and a rear cylinder. The rear end of the front cylinder is fitted onto the front end of the rear cylinder. An optical imaging component and an acoustic imaging component are disposed at the front end of the front cylinder. A front-end gripping airbag is fitted and fixed to the front section of the front cylinder, and the front-end gripping airbag is connected to a front-end inflation pump. A front centering support roller assembly and a middle centering support roller assembly are also disposed on the front cylinder. A rear-end gripping airbag is fitted and fixed to the rear cylinder, and the rear-end gripping airbag is connected to a rear-end inflation pump. The upper part is also equipped with a rear centering support roller assembly. The drive fixing module is fixed in the front cylinder. The drive fixing module is equipped with a forward drive module for driving the forward drive shaft to extend and retract. The front end face of the rear cylinder is equipped with a measurement fixing end panel. The measurement fixing end panel is connected to the forward drive shaft. The measurement fixing end panel is equipped with a measurement axial drive module for driving the measurement axial drive shaft to extend and retract. The measurement axial drive shaft is equipped with a measurement circumferential drive module. The measurement circumferential drive module is equipped with a visual-optical-acoustic-magnetic measurement module and a well positioning module.

[0007] As described above, the visual-optical-acoustic-magnetic measurement module includes sensors such as an optical camera for acquiring images of the borehole wall surface, a laser probe for acquiring information on the contour undulations of the borehole wall surface, an acoustic probe for acquiring information on shallow surface fractures of the borehole wall, and an electromagnetic probe for acquiring information on deep surface fractures of the borehole wall. Sensors of the same type are evenly arranged in a ring, and the signal detection directions of different types of sensors are all perpendicular to the central axis. The central axis, the central axis of the front cylinder, and the central axis of the rear cylinder are collinear. The optical imaging component, the acoustic imaging component, the front-end air pump, the forward drive module, the measurement axial drive module, the measurement circumferential drive module, the visual-optical-acoustic-magnetic measurement module, and the downhole positioning module are all connected to the downhole control module.

[0008] As described above, the middle section inner wall and the rear section inner wall of the front cylinder are respectively provided with a middle section limit module and a rear section limit module. The measuring fixed end panel is located between the middle section limit module and the rear section limit module. A piston ring is sleeved on the outer periphery of the measuring fixed end panel. A sliding groove is provided on the outer wall of the rear cylinder for the rear section limit module to slide. A proximity switch is provided on the measuring fixed end panel.

[0009] A method for in-situ measurement of deep fissures using a combination of optoacoustic and magnetic fields includes the following steps:

[0010] Step 1: Assemble the measuring robot and place it into the borehole to be tested. Both the front and rear gripping airbags are inflated. The optical and acoustic imaging components begin to operate. If there are foreign objects in the forward sensing area or the measuring robot cannot adapt to the environment, stop the test. If a slit network exists in the forward sensing area, proceed to step 8; if no slit network exists in the forward sensing area, proceed to step 2.

[0011] Step 2, initial contraction: The downhole control module controls the rear-end gripping airbag to contract, proceeding to Step 3.

[0012] Step 3: Initial forward movement. The downhole control module controls the forward drive shaft to retract via the forward drive module. When the measuring fixed end panel moves to the trigger mid-section limit module, the forward drive shaft stops retracting, and the process proceeds to Step 4.

[0013] Step 4: Initial expansion. The downhole control module controls the rear-end gripping airbag to expand, proceeding to Step 5.

[0014] Step 5: Secondary contraction. The downhole control module controls the front-end gripping airbag to contract, proceeding to step 6.

[0015] Step 6: Second forward movement. The downhole control module's forward drive module controls the extension of the forward drive shaft. When the measuring fixed end panel moves to trigger the response of the rear limit module, the forward drive shaft stops extending, and the process proceeds to Step 7.

[0016] Step 7: Secondary expansion. The downhole control module controls the expansion of the front-end gripping airbag, proceeding to step 8.

[0017] Step 8: Perform axial measurement, that is, first complete the single-azimuth axial step scan, then complete the next azimuth axial step scan, until the omnidirectional axial step scan is completed.

[0018] Alternatively, circumferential measurement can be performed, that is, first complete a circumferential scan at a certain depth, and then complete the next circumferential scan at the next depth, until the full depth circumferential scan is completed;

[0019] Alternatively, axial and circumferential measurements can be performed sequentially.

[0020] After performing axial and circumferential measurements in sequence, the acquired axial measurement data and the acquired circumferential measurement data of the same type are weighted and averaged according to the principle of depth and orientation correspondence. Both axial and circumferential measurement data include borehole wall surface image information, borehole wall surface contour undulation information, shallow borehole wall fracture information, and deep borehole wall fracture information.

[0021] A method for in-situ measurement of deep fractures using a combination of optoacoustic and magnetic fields, including a data borehole relocation step:

[0022] The following matrices are used to store the borehole wall surface image information, borehole wall surface contour undulation information, shallow surface crack information, and deep surface crack information: FD[ ][ ], LD[ ][ ], SD[ ][ ], and RD[ ][ ], respectively. FD[n1][h1] represents the borehole wall surface image information at depth h1 in azimuth of borehole n1, LD[n1][h1] represents the borehole wall surface contour undulation information at depth h1 in azimuth of borehole n1, SD[n1][h1] represents the shallow surface crack information at depth h1 in azimuth of borehole n1, and RD[n1][h1] represents the deep surface crack information at depth h1 in azimuth of borehole n1.

[0023] Binarize the matrix FD[ ][ ] to form a binary image matrix FFD[ ][ ]; binarize the matrix LD[ ][ ] to form a binary image matrix LLD[ ][ ]; superimpose the elements of the binary image matrix FFD[ ][ ] and the binary image matrix LLD[ ][ ] corresponding to the orientation and depth to form a binary image matrix RH[ ][ ]; calculate the maximum width H[ ][ ]max and minimum width H[ ][ ]min of the fracture region in the binary image matrix RH[ ][ ] along the borehole center axis direction;

[0024] Binarize the matrix SD[ ][ ] to form a binary image matrix SSD[ ][ ], and calculate the coordinates (SW[ ][ ]1, SH[ ][ ]1) of the single-sided curve vertex Ssd1 of the hyperbola closest to the borehole center axis. SW[ ][ ]1 represents the horizontal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Ssd1, and SH[ ][ ]1 represents the vertical coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Ssd1. Calculate the coordinates (SW[ ][ ]2, SH[ ][ ]2) of the single-sided curve vertex Ssd1 that is farthest from the borehole center axis. SW[ ][ ]2 represents the horizontal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Ssd1. ]2 represents the longitudinal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of point Ssd2. Calculate the width SHW[ ][ ] of the crack in the image region corresponding to the element of the matrix SSD[ ][ ] at each orientation and depth.

[0025] ;

[0026] Where vs[ ][ ] represents the sound wave propagation speed of the image region corresponding to the elements of the matrix SSD[ ][ ] corresponding to the orientation and depth of the single-sided curve vertex Ssd1;

[0027] The matrix RD[ ][ ] is binarized to form a binary image matrix RRD[ ][ ]. The coordinates (RW[ ][ ]1, RH[ ][ ]1) of the single-sided curve vertex Rrd1, which is closest to the borehole center axis, are calculated. RW[ ][ ]1 represents the horizontal coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Rrd1. RH[ ][ ]1 represents the vertical coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Rrd1. The coordinates (RW[ ][ ]2, RH[ ][ ]2) of the point Rrd2, which is farthest from the borehole center axis on the single-sided curve where the single-sided curve vertex Rrd1 is located, are calculated. RW[ ][ ]2 represents the horizontal coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Rrd1. RH[ ][ ]1 represents the vertical coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Rrd1. ]2 represents the longitudinal coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of point Rrd2. Calculate the width RHW[ ][ ] of the crack in the image region corresponding to the element of matrix RRD[ ][ ] at each orientation and depth.

[0028] ;

[0029] Where vr[ ][ ] represents the electromagnetic wave propagation speed of the image region corresponding to the elements of the binary image matrix RRD[ ][ ] corresponding to the orientation and depth of the single-sided curve vertex Rrd1.

[0030] A method for in-situ measurement of deep fractures using a combination of optoacoustic and magnetic resonance imaging (EMI) further includes a fracture network reconstruction step, which includes:

[0031] This includes: reconstructing the image regions corresponding to the elements of the binary image matrix RH[ ][ ] at various orientations and depths into a borehole wall annular segment with a set thickness in the borehole radial direction; and reconstructing the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] within the borehole wall annular segment. Specifically: if the maximum height H[ ][ ]max of the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] is 0, no cracks are set in the borehole wall annular segment; if the maximum height H[ ][ ]max of the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] is greater than 0, cracks are placed at the same height as the cracks in the image regions of the corresponding elements of the binary image matrix RH[ ][ ] within the borehole wall annular segment. At each point on the plane where the height of the cracks is located within the borehole wall annular segment, the height of the cracks is randomly selected from the maximum height H[ ][ ]max to the minimum height H[ ][ ]. The values ​​between ]min, the annular segments corresponding to each azimuth at the same depth are spliced ​​together to form a complete borehole wall annular column, that is, the borehole wall annular column is divided equally by azimuth to form borehole wall annular column segments.

[0032] A method for in-situ measurement of deep fractures using a combined optical, acoustic, and magnetic field (OSF) approach includes: reconstructing the image regions corresponding to the elements of the matrix SSD[ ][ ] at various orientations and depths into near-field annular cylindrical sections with a set thickness in the borehole radial direction; and reconstructing the fractures in the image regions corresponding to the elements of the matrix SSD[ ][ ] within the near-field annular cylindrical sections. Specifically, if the fracture height SHW[ ][ ] of the image regions corresponding to the elements of the matrix SSD[ ][ ] is 0, no fractures are set in the near-field annular cylindrical sections; if the fracture height SHW[ ][ ] of the image regions corresponding to the elements of the matrix SSD[ ][ ] is greater than 0, fractures are placed at the same height as the fractures in the image regions corresponding to the elements of the matrix SSD[ ][ ] within the near-field annular cylindrical sections. At each point on the plane where the height of the fracture placement is located within the near-field annular cylindrical sections, the height of the fracture is the fracture height SHW[ ][ ]. A crack of fixed height is generated, and the near-field annular segments corresponding to each direction at the same depth are spliced ​​together to form a complete near-field annular segment, that is, the near-field annular segment is formed by dividing the near-field annular segment into equal parts according to the number of directions.

[0033] A method for in-situ measurement of deep fractures using a combined optical, acoustic, and magnetic field approach includes: reconstructing the image regions corresponding to the elements of the matrix RRD[ ][ ] at various orientations and depths into far-field annular segments with a set thickness in the borehole radial direction; and reconstructing the fractures in the image regions corresponding to the elements of the matrix RRD[ ][ ] within the far-field annular segments. Specifically: if the fracture height RHW[ ][ ] of the image regions corresponding to the elements of the matrix RRD[ ][ ] is 0, no fractures are set in the far-field annular segments; if the fracture height RHW[ ][ ] of the image regions corresponding to the elements of the matrix RRD[ ][ ] is greater than 0, fractures are placed at the same height as the fractures in the image regions corresponding to the elements of the matrix RRD[ ][ ] within the far-field annular segments; and at each point on the plane where the fracture height is located within the far-field annular segments, the fracture height is the fracture height RHW[ ][ ]. A crack of fixed height is generated, and the far-field ring column segments corresponding to each direction at the same depth are spliced ​​together to form a complete far-field ring column, that is, the far-field ring column is divided equally by the number of directions to form far-field ring column segments.

[0034] A method for in-situ measurement of deep fissures using a combination of optoacoustic and magnetic fields further includes the following steps:

[0035] For the reconstructed crack within the near-field annular column segment, both the radial and tangential flip axes pass through the center of the crack. These axes lie in the same plane and are perpendicular to the corresponding central axis of the near-field annulus. The radial flip axis is perpendicular to the central axis of the near-field annulus, and the tangential flip axis is perpendicular to the radial flip axis.

[0036] If a crack is present within the current near-field annular segment, the following two steps are performed:

[0037] The first step is to search for cracks in the adjacent borehole wall sections above and below the current near-field borehole section. If a crack is found in one of the borehole wall sections, the crack in the current near-field borehole section is flipped around the tangential flip axis so that the crack in the current near-field borehole section points to the crack in the borehole wall section. The crack in the current near-field borehole section is then superimposed with the fluctuation characteristics of the value between the maximum height H[ ][ ]max and the minimum height H[ ][ ]min based on the corresponding crack height SHW[ ][ ]. If no cracks are found in the adjacent borehole wall sections above and below the same orientation, the crack in the current near-field borehole section is then superimposed with the fluctuation characteristics of the value between the height SHW[ ][ ] / 5 and SHW[ ][ ] / 8 based on the corresponding crack height SHW[ ][ ].

[0038] The second step is to search for cracks in the near-field annular segments above and below the current near-field annular segment. If a crack is found in one of the near-field annular segments above and below the current near-field annular segment, the crack in the current near-field annular segment is flipped around the radial flip axis so that the crack in the current near-field annular segment points to the crack in the searched near-field annular segment.

[0039] A method for in-situ measurement of deep fissures using a combination of optoacoustic and magnetic fields further includes the following steps:

[0040] For the fracture reconstructed within the far-field annular segment, both the radial and tangential flip axes pass through the center of the fracture. These axes lie in the same plane and are perpendicular to the central axis of the corresponding far-field annulus. The radial flip axis is perpendicular to the central axis of the far-field annulus, and the tangential flip axis is perpendicular to the radial flip axis.

[0041] If a crack is present within the current far-field annular segment, then the following two steps are performed:

[0042] The first step is to search for cracks in the adjacent near-field toroidal segments at the same orientation as the current far-field toroidal segment. If a crack is found in one of the near-field toroidal segments, the crack in the current far-field toroidal segment is flipped around the tangential flip axis so that the crack in the current far-field toroidal segment points to the crack in the near-field toroidal segment. The crack in the current far-field toroidal segment is then superimposed with the fluctuation characteristics of the value between SHW[ ][ ] / 5 and SHW[ ][ ] / 8 based on the corresponding crack height RHW[ ][ ]. If no cracks are found in the adjacent near-field toroidal segments at the same orientation, the crack in the current far-field toroidal segment is not flipped around the tangential flip axis. The crack in the current far-field toroidal segment is then superimposed with the fluctuation characteristics of the value between RHW[ ][ ] / 5 and RHW[ ][ ] / 8 based on the corresponding crack height RHW[ ][ ].

[0043] The second step is to search for cracks in the adjacent far-field toroidal segments above and below the current far-field toroidal segment. If a crack is found in one of the adjacent far-field toroidal segments above and below the current far-field toroidal segment, the crack in the current far-field toroidal segment is flipped around the radial flip axis so that the crack in the current far-field toroidal segment points to the crack in the searched far-field toroidal segment.

[0044] The present invention has the following advantages over the prior art:

[0045] 1) High detection accuracy. By selecting and integrating high-precision optical imaging components, acoustic imaging components, optical cameras, laser probes, acoustic probes, and electromagnetic probes, it is possible to effectively measure and scan the fracture network characteristics of geological boreholes at different depths and scales in real time. In the case of in-depth excavation and utilization of multi-source data, it can effectively improve measurement accuracy, has low cost, strong versatility, and is easy to replace after partial damage to the device.

[0046] 2) Strong adaptability. The entire device adopts a front and rear airbag drive. Through ingenious structural design, the device can adapt to boreholes of different sizes and shapes, ensuring that the device is centered during the measurement process. At the same time, it can maintain water and advance in the measurement area with uneven borehole walls, improving the situation that traditional non-centered and waterless environments are prone to measurement failure, and greatly improving the adaptability of the entire device.

[0047] 3) More diverse measurement methods. The entire device can utilize the forward-looking sensing module to obtain fracture network data in front of the borehole, and can also utilize the measurement control components to acquire fracture network data on the borehole wall surface, borehole undulations, shallow surface, and deep surface, covering comprehensive measurement data of the fracture area. In addition, depending on the test target, it can perform both axial and circumferential measurements. Using these two different measurement methods can improve the accuracy of axial and circumferential measurements respectively. The diverse measurement methods enable the overall device and method to adapt to more application scenarios.

[0048] 4) Simple measurement method. The measurement robot is lowered into the borehole simply by transmitting a cable. The robot can then perform feature area perception and search, autonomous navigation, and rapid acquisition of multi-source data. Combined with subsequent data processing methods, high-precision in-situ measurement and visualization of deep fracture networks can be achieved.

[0049] 5) This invention is highly efficient in data processing. With a small amount of data processing, it can simultaneously improve the measurement accuracy of deep fracture networks and realize the three-dimensional reconstruction and visualization of multi-dimensional spatial fracture networks on the borehole wall surface, shallow surface and deep surface. The obtained data is richer and the results are more reliable, which greatly improves the measurement efficiency.

[0050] 6) The structural system and overall layout of the present invention are simple and easy to implement.

[0051] In summary, this invention effectively solves the problems of single, insufficiently fused, and difficult-to-model in-situ measurement data of deep fracture networks, while simultaneously improving the measurement accuracy of deep fracture networks. It achieves three-dimensional reconstruction and visualization of multi-dimensional spatial fracture networks on the borehole wall surface, shallow surface, and deep surface. By combining optical imaging components, acoustic imaging components, optical cameras, laser probes, acoustic probes, and electromagnetic probes, it can acquire fracture network data in front of the borehole and utilize measurement control components to acquire fracture network data on the borehole wall surface, borehole undulations, shallow surface, and deep surface, covering comprehensive measurement data of the fracture region. Furthermore, this invention employs a front and rear airbag drive system. Through ingenious structural design, the overall device can adapt to boreholes of different sizes and shapes, ensuring the device remains centered during measurement. Simultaneously, it can maintain water retention and advance in measurement areas with uneven borehole walls, improving upon the traditional methods that easily lead to measurement failures in non-centered or waterless environments, significantly enhancing the adaptability of the entire device. This method and device are ingeniously designed, rigorously conceived, have a simple structural system, and are easy to implement. Attached Figure Description

[0052] Figure 1 This is a structural block diagram of the device of the present invention;

[0053] Figure 2 This is a schematic diagram of the robot's structure.

[0054] Figure 3 A schematic diagram for measuring the robot's perception of the hole wall;

[0055] Figure 4 This is a schematic diagram of the robot's initial retraction.

[0056] Figure 5 This is a schematic diagram of the robot's initial forward movement.

[0057] Figure 6 A schematic diagram for measuring the initial expansion of the robot;

[0058] Figure 7 This is a schematic diagram of the robot's secondary contraction.

[0059] Figure 8 This is a schematic diagram of the robot's second forward movement.

[0060] Figure 9 A schematic diagram for measuring the secondary expansion of the robot;

[0061] Figure 10 This is a schematic diagram of the data drilling and positioning.

[0062] Figure 11 This is a schematic diagram showing the width of matrix RH;

[0063] Figure 12A schematic diagram of the feature points of the SSD matrix;

[0064] Figure 13 This is a schematic diagram of the feature points of the RRD matrix;

[0065] Figure 14 Here is a schematic diagram of matrix KB, where KB[ ][ ] is the matrix corresponding to the annular column section of the borehole wall, and KBqx[ ][ ] is the matrix corresponding to the cracks in the annular column section of the borehole wall.

[0066] Figure 15 Here is a schematic diagram of matrix JC, where JC[ ][ ] is the matrix corresponding to the near-field annular column segment, and JCqx[ ][ ] is the matrix corresponding to the cracks within the near-field annular column segment;

[0067] Figure 16 Here is a schematic diagram of matrix YC, where YC[ ][ ] is the matrix corresponding to the far-field annular column segment, and YCqx[ ][ ] is the matrix corresponding to the cracks within the far-field annular column segment.

[0068] In the diagram: 1-Forward sensing module; 2-Front-end drive module; 3-Centered support roller; 4-Drive control component; 5-Measurement control component; 6-Rear drive module; 7-Robot tail cable; 8-Central axis; 9-Front cylinder; 10-Rear cylinder; 2.1-Front-end air pump; 2.2-Front-end gripping airbag; 4.1-Drive fixing module; 4.2-Forward drive module; 4.3-Forward drive shaft; 4.4-Middle section limit module; 4.5-Rear section limit module; 5.1-Measurement fixing end panel; 5.2-Measurement axial drive module; 5.3-Measurement axial drive shaft; 5.4-Measurement circumferential drive module; 5.5-Visual-optical-acoustic-magnetic measurement module; 5.6-Downhole control module; 5.7-Downhole positioning module; 5.8-Downhole power supply module; 6.1-Rear air pump; 6.2-Rear gripping airbag. Detailed Implementation

[0069] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0070] Example 1:

[0071] like Figure 1As shown, a deep fracture co-operated in-situ measurement device includes a measurement robot placed inside the borehole, a cable lowering device placed near the borehole opening, and a host computer placed around the borehole. The measurement robot is cylindrical and operates normally in geological boreholes or other inspection holes, enabling in-situ measurement of fracture networks at different locations within the borehole and possessing autonomous movement capabilities. The cable lowering device primarily uses a depth editor to perceive the depth position of the measurement robot and establishes data communication between the measurement robot and the host computer. The host computer serves as the core control and data interaction platform for the measurement robot, enabling it to perceive the robot's status and data, and perform functions such as control, calculation, analysis, display, storage, and playback of the corresponding data.

[0072] like Figure 2 As shown, the measurement robot includes a front cylinder, a rear cylinder, a front-view perception module 1, a front-end drive module 2, a central support roller 3, a drive control component 4, a measurement control component 5, a rear-end drive module 6, a robot tail cable 7, a front-end air pump 2.1, a front-end gripping airbag 2.2, a drive fixing module 4.1, a forward drive module 4.2, a forward drive shaft 4.3, a mid-section limit module 4.4, a rear-section limit module 4.5, a measurement fixing end panel 5.1, a measurement axial drive module 5.2, a measurement axial drive shaft 5.3, a measurement circumferential drive module 5.4, a visual-optical-acoustic-magnetic measurement module 5.5, a downhole control module 5.6, a downhole positioning module 5.7, a downhole power supply module 5.8, a rear-end air pump 6.1, and a rear-end gripping airbag 6.2.

[0073] The forward-looking perception module 1 mainly realizes the position tracking of the hole wall crack network at the bottom of the measurement robot. The forward-looking perception module 1 is shaped like a frustum or a cylinder and is located at the front end of the measurement robot, that is, the forward-looking perception module 1 is set at the front end of the front cylinder. The forward-looking perception module 1 includes an optical imaging component and an acoustic imaging component. The optical imaging component includes a light source and a camera, and the acoustic imaging component includes an array of acoustic transducers. The forward-looking perception module 1 can realize real-time imaging of the hole wall at the front end of the measurement robot. The optical imaging component mainly realizes real-time forward imaging of the hole wall in dry hole or clean water drilling environment, and the acoustic imaging component mainly realizes real-time forward imaging of the hole wall in non-clean water or non-uniform fluid drilling environment.

[0074] The front-end drive module 2 mainly serves as the front-end drive component for the forward movement of the measurement robot. The front-end drive module 2 is annular and located at the front section of the front cylinder. It includes a front-end air pump 2.1 and a front-end gripping airbag 2.2. The front-end gripping airbag 2.2 is fitted and fixed to the front section of the front cylinder. The front-end air pump 2.1 is located inside the front cylinder and is connected to the front-end gripping airbag 2.2 via an inflation / deflation pipe. The inflation and deflation of the front-end air pump 2.1 enables the expansion and compression of the front-end gripping airbag 2.2. The front-end gripping airbag 2.2 is made of wear-resistant material, and several small gripping pins are distributed on its outer surface. When the front-end gripping airbag 2.2 is inflated, it increases the friction between the front-end gripping airbag 2.2 and the borehole wall. When compressed, the maximum outer diameter of the front-end gripping airbag 2.2 is smaller than the size of the test borehole.

[0075] The centering support roller 3 mainly serves as the centering component of the measuring robot. The centering support roller 3 is divided into a front centering support roller group, a middle centering support roller group, and a rear centering support roller group. The front centering support roller group and the middle centering support roller group are set on the front cylinder, and the rear centering support roller group is set on the rear cylinder. The rear end of the rear cylinder is closed, and the rear end of the front cylinder is fitted onto the front end of the rear cylinder. The centering support roller 3 is composed of multiple rollers evenly distributed around its circumference. The multiple rollers on the centering support roller 3 can rotate with the measuring robot during its movement. The circumference formed by the centering support roller 3 is slightly smaller than the size of the test borehole.

[0076] The drive control assembly 4 primarily serves as the drive control component for the measuring robot. Located in the front-middle section of the robot, it includes a drive fixing module 4.1, a forward drive module 4.2, a forward drive shaft 4.3, a mid-section limit module 4.4, and a rear-section limit module 4.5. The drive fixing module 4.1 is fixed within the front cylinder and primarily functions as the core for securing the internal components of the robot's drive control assembly. The forward drive module 4.2 is mounted on the drive fixing module 4.1. This module drives the forward drive shaft 4.3 to extend and retract. The forward drive shaft 4.3 is an electrically controlled telescopic rod, and the forward drive module 4.2 controls its extension and retraction. [Front cylinder...] The middle section inner wall and the rear section inner wall are respectively equipped with a middle section limiting module 4.4 and a rear section limiting module 4.5. The middle section limiting module 4.4 and the rear section limiting module 4.5 mainly realize the limiting of the measuring fixed end panel 5.1, ensuring that the measuring fixed end panel 5.1 is between the middle section limiting module 4.4 and the rear section limiting module 4.5. A piston ring is fitted on the outer periphery of the measuring fixed end panel 5.1, and the piston ring realizes the sealing between the front cylinder and the rear cylinder. The outer wall of the rear cylinder is provided with a sliding groove for the rear section limiting module 4.5 to slide. A proximity switch is provided on the measuring fixed end panel 5.1. If the measuring fixed end panel 5.1 just moves to contact the middle section limiting module 4.4 or the rear section limiting module 4.5, the proximity switch generates feedback, and the forward drive module 4.2 stops working.

[0077] The measurement control component 5 primarily serves as the measurement control part of the measurement robot. Located in the middle to rear of the robot, it includes a measurement fixed end panel 5.1 mounted on the front end face of the rear cylinder, and further includes a measurement axial drive module 5.2, a measurement axial drive shaft 5.3, a measurement circumferential drive module 5.4, a visual-optical-acoustic-magnetic measurement module 5.5, a downhole control module 5.6, a downhole positioning module 5.7, and a downhole power supply module 5.8, all housed within the rear cylinder. The measurement fixed end panel 5.1 primarily functions as the core fixing unit for the internal components of the measurement control component. The measurement fixed end panel 5.1 is connected to the forward drive... Shaft 4.3 is aligned with the central axis. The measuring fixed end panel 5.1 is fixed on the forward drive shaft 4.3. The extension and retraction of the forward drive shaft 4.3 can drive the measuring fixed end panel 5.1 to move within the front cylinder, thereby causing the overall extension and retraction of the front and rear cylinders. A measuring axial drive module 5.2 is installed on the measuring fixed end panel 5.1. The measuring axial drive module 5.2 drives the measuring axial drive shaft 5.3 to extend and retract. The measuring axial drive module 5.2 can control the extension and retraction of the measuring axial drive shaft 5.3. A measuring circumferential drive module 5.4 is installed at the rear end of the measuring axial drive shaft 5.3. A viewing device is installed on the measuring circumferential drive module 5.4. The optical-acoustic-magnetic measurement module 5.5 and the wellbore positioning module 5.7, along with the axial drive shaft 5.3, enable the synchronous extension and retraction of the circumferential drive module 5.4 and the visual-optical-acoustic-magnetic measurement module 5.5. The circumferential drive module 5.4 allows for the circumferential rotation of the visual-optical-acoustic-magnetic measurement module 5.5. The visual-optical-acoustic-magnetic measurement module 5.5 is cylindrical and contains various types of sensors, including optical cameras, laser probes, acoustic probes, and electromagnetic probes. Sensors of the same type are evenly arranged in a ring on the visual-optical-acoustic-magnetic measurement module 5.5, while sensors of different types... Sensors can also be staggered at the same height. The signal detection directions of different types of sensors are perpendicular to the central axis 8 (central axis 8, the central axis of the front cylinder, and the central axis of the rear cylinder are collinear). The optical camera included in the visual-optical-acoustic-magnetic measurement module 5.5 can acquire image information of the borehole wall surface. The laser probe included in the visual-optical-acoustic-magnetic measurement module 5.5 can acquire information of the borehole wall surface contour undulation. The acoustic probe included in the visual-optical-acoustic-magnetic measurement module 5.5 can acquire information of shallow surface cracks in the borehole wall. The electromagnetic probe included in the visual-optical-acoustic-magnetic measurement module 5.5 can acquire information of deep surface cracks in the borehole wall. The rear cylinder sidewall corresponding to the position of the visual-optical-acoustic-magnetic measurement module 5.5 is set as a transparent sidewall.The downhole control module 5.6 enables the control and management of all data of the measurement robot, as well as data feedback with the host computer. The downhole control module 5.6 controls and collects data from the forward-looking perception module 1, the front-end air pump 2.1, the forward drive module 4.2, the measurement axial drive module 5.2, the measurement circumferential drive module 5.4, the visual-optical-acoustic-magnetic measurement module 5.5, and the downhole positioning module 5.7. The downhole control module 5.6 transmits data and control commands to and from the host computer. The downhole positioning module 5.7 enables real-time perception of the measurement robot's orientation information, providing geographical location data for data interpretation. The downhole power supply module 5.8 included in the measurement control component 5 enables power supply and power data management for all sensors and power-requiring modules of the measurement robot.

[0078] The rear drive module 6 mainly serves as the rear drive component for the forward movement of the measurement robot. The rear drive module 6 is annular and is fitted and fixed to the rear section of the rear cylinder. It includes a rear air pump 6.1 and a rear gripping airbag 6.2. The rear air pump 6.1 is located inside the rear cylinder and is connected to the rear gripping airbag 6.2 via an air inflator / deflater pipe. The rear gripping airbag 6.2 is fitted and fixed to the rear cylinder. The inflation and deflation of the rear air pump 6.1 enables the expansion and compression of the rear gripping airbag 6.2. The rear gripping airbag 6.2 is made of wear-resistant material, and its outer surface is covered with several small gripping pins. When the rear gripping airbag 6.2 is inflated, it increases the friction between the rear gripping airbag 6.2 and the borehole wall. The maximum outer diameter of the rear drive module 6 is smaller than the size of the test borehole.

[0079] The robot tail cable 7 mainly enables data communication between the measurement robot and the host computer. The robot tail cable 7 includes cables and steel wire ropes or nylon wires. The rear end of the rear cylinder is connected to the steel wire ropes or nylon wires. The cables are wound on the steel wire ropes or nylon wires, and both ends are connected to the host computer and the downhole control module 5.6, respectively. It has a certain anti-drag capability. If the measurement robot is trapped in the hole, it can be used to drag the measurement robot.

[0080] The central axis 8 is the central axis of the measuring robot. The central axes of the front-view perception module 1, the front-end drive module 2, the central support roller 3, the drive control component 4, the measurement control component 5, and the rear-end drive module 6 coincide with the central axis 8.

[0081] Example 2:

[0082] like Figure 3-9As shown, a method for in-situ measurement of deep fractures using a combined optical, acoustic, and magnetic field (OAF) approach, utilizing the in-situ OAF approach device described in Example 1, includes the following steps:

[0083] Step 1: Hole Wall Sensing. The measurement robot is assembled and placed into the borehole to be tested. Both the front-end drive module 2 and the rear-end drive module 6 are in an expanded state. The forward-looking perception module 1 begins operation, performing real-time imaging of the borehole wall in the sensing area ahead. This data is transmitted to the host computer via the downhole control module 5.6 and cable. Based on the acquired real-time borehole wall imaging, the forward-looking perception module 1 determines the presence of a fracture network in the sensing area and sends a signal Y (indicating the presence of a fracture network) to the downhole control module 5.6, proceeding to Step 8. Alternatively, if the forward-looking perception module 1 determines the absence of a fracture network in the sensing area based on the acquired real-time borehole wall imaging, it sends a signal N (indicating the absence of a fracture network) to the downhole control module 5.6, proceeding to Step 2. If foreign objects are present in the sensing area or the measurement robot cannot adapt to the environment, the test is stopped.

[0084] The presence of a gap network in the sensing area ahead can be detected by setting a threshold.

[0085] The threshold judgment involves the forward-looking perception module 1 performing corresponding digital image processing on the real-time borehole wall imaging to form a binary image containing only fractures and non-fractures. If the proportion of fractures is greater than the previously set threshold, it is determined that a fracture network exists in the real-time borehole wall imaging, and the forward-looking perception module 1 sends signal Y to the downhole control module 5.6. If the proportion of fractures is less than or equal to the previously set threshold, it is determined that no fracture network exists in the real-time borehole wall imaging, and the forward-looking perception module 1 sends signal N to the downhole control module 5.6.

[0086] Step 2, initial contraction: The downhole control module 5.6 sends a contraction command to the rear drive module 6. The rear gripping airbag 6.2 of the rear drive module 6 contracts, and the outer surface of the rear gripping airbag 6.2 separates from the borehole wall, proceeding to step 3.

[0087] Step 3, Initial Advancement: The downhole control module 5.6 sends a retraction command to the drive control component 4. That is, the downhole control module 5.6 controls the forward drive shaft 4.3 to retract through the forward drive module 4.2. The measurement control component 5 moves forward relative to the borehole wall along the forward drive shaft 4.3. When the measurement control component 5 moves to trigger the response of the intermediate limit module 4.4, the intermediate limit module 4.4 sends a stop retraction command to the drive control component 4. The measurement control component 5 stops moving forward and proceeds to step 4.

[0088] Step 4, initial expansion: The downhole control module 5.6 sends an expansion command to the back-end drive module 6, and the back-end drive module 6 expands. That is, the downhole control module 5.6 controls the back-end gripping airbag 6.2 to expand. The outer surface of the back-end gripping airbag 6.2 is squeezed against the borehole wall, and then proceed to step 5.

[0089] Step 5, Secondary contraction: The downhole control module 5.6 sends a contraction command to the front-end drive module 2, and the front-end drive module 2 contracts. That is, the downhole control module 5.6 controls the front-end gripping airbag 2.2 to contract, and the outer surface of the front-end gripping airbag 2.2 separates from the borehole wall, proceeding to step 6.

[0090] Step 6: Second forward movement. The downhole control module 5.6 sends an extension command to the drive control component 4. The drive control component 4 moves forward relative to the borehole wall along the forward drive shaft 4.3. That is, the downhole control module 5.6 and the forward drive module 4.2 control the forward drive shaft 4.3 to extend. When the measuring fixed end panel 5.1 triggers the response of the rear limit module 4.5, the rear limit module 4.5 sends a stop extension command to the drive control component 4. The drive control component 4 stops moving forward, the forward drive shaft 4.3 stops extending, and the process proceeds to step 7.

[0091] Step 7: Secondary expansion. The downhole control module 5.6 sends an expansion command to the front-end drive module 2. The downhole control module 5.6 controls the front-end gripping airbag 2.2 to expand. The outer surface of the front-end gripping airbag 2.2 is squeezed against the borehole wall, and the process proceeds to step 8.

[0092] Step 8: In order to ensure the accuracy of axial measurement of borehole wall cracks or overall measurement accuracy, axial measurement is performed. Then, both the front gripping airbag 2.2 and the rear gripping airbag 6.2 are retracted to retrieve the measurement robot.

[0093] Alternatively, to improve efficiency and ensure the accuracy of circumferential measurement of the hole wall cracks, circumferential measurement can be performed, and then both the front gripping airbag 2.2 and the rear gripping airbag 6.2 can be retracted to retrieve the measurement robot.

[0094] Alternatively, to simultaneously ensure both axial and circumferential measurement accuracy, axial and circumferential measurements are performed sequentially. The axial measurement data (hole wall surface image information, hole wall surface contour undulation information, shallow hole wall fracture information, and deep hole wall fracture information) and the same type of circumferential measurement data (hole wall surface image information, hole wall surface contour undulation information, shallow hole wall fracture information, and deep hole wall fracture information) are weighted and averaged according to the principle of depth and orientation correspondence. The more abundant the axial and circumferential measurement data at the same location and depth in the borehole, the greater the weighting percentage. Compared to the traditional single circumferential measurement method, this approach can consider both circumferential and axial data, significantly improving the overall measurement accuracy at all directions and depths in the borehole. If axial measurement accuracy is prioritized, the weight of axial measurement data is greater than that of circumferential measurement data; conversely, if circumferential measurement data is prioritized, the weight of axial measurement data is less than that of circumferential measurement data. Then, both the front-end gripping airbag 2.2 and the rear-end gripping airbag 6.2 retract, retrieving the measurement robot.

[0095] Axial measurement involves first completing a single-azimuth axial step scan, then completing the next azimuth axial step scan, until a full-range axial step scan is completed. The visual-optical-acoustic-magnetic (AV-AM) measurement module 5.5 starts working, simultaneously acquiring borehole wall surface image information, borehole wall surface contour undulation information, and shallow surface crack information. 5.5 Synchronously acquire information on deep surface cracks in the borehole wall. After the visual-optical-acoustic-magnetic measurement module 5.5 completes one measurement in a single orientation, it stops working. The measurement axis drive module 5.2 then starts working. The measurement axis drive module 5.2 drives the visual-optical-acoustic-magnetic measurement module 5.5 forward a fixed length along the measurement axis drive shaft 5.3. After that, the measurement axis drive module 5.2 stops working, and the visual-optical-acoustic-magnetic measurement module 5.5 starts one measurement operation until the axial scan of the borehole periphery in that orientation is completed. The circumferential measurement drive module 5.4 starts working. After the circumferential measurement drive module 5.4 drives the visual-optical-acoustic-magnetic measurement module 5.5 to rotate at a fixed angle, the circumferential measurement drive module 5.4 stops working. With the cooperation of the visual-optical-acoustic-magnetic measurement module 5.5 and the measurement axial drive module 5.2, the axial step scan of this position is completed. With the mutual cooperation of the visual-optical-acoustic-magnetic measurement module 5.5, the circumferential measurement drive module 5.4, and the measurement axial drive module 5.2, the synchronous acquisition of borehole wall surface image information, borehole wall surface contour undulation information, shallow borehole wall fracture information, and deep borehole wall fracture information of the borehole periphery in the area where the measurement robot is located is completed. The downhole control module 5.6 transmits the borehole wall surface image information, borehole wall surface contour undulation information, shallow borehole wall fracture information, and deep borehole wall fracture information of the area where the measurement robot is located, along with the azimuth information acquired by the downhole positioning module 5.7, to the host computer via cable. At the same time, the host computer records the depth position information in the cable lowering device.

[0096] Circumferential measurement involves first completing a circumferential scan at a certain depth, then completing the next circumferential scan at the next depth, until a full-depth circumferential scan is completed. The visual-optical-acoustic-magnetic (AV-AM) measurement module 5.5 starts working, simultaneously acquiring surface image information of the borehole wall, information on the contour undulations of the borehole wall surface, information on shallow surface cracks in the borehole wall, and information on deep surface cracks in the borehole wall. After completing one measurement cycle, the AV-optical-acoustic-magnetic (AV-AM) measurement module 5.5 stops working, and the circumferential measurement drive module 5.4 starts working. The circumferential measurement drive module 5.4 drives the AV-optical-acoustic-magnetic (AV-AM) measurement module 5.5 to rotate a fixed angle, then stops working, and the AV-optical-acoustic-magnetic (AV-AM) measurement module 5.5 begins a measurement cycle until the circumference of the borehole at that depth is scanned. The axial measurement drive module... 5.2 Upon commencement of operation, the axial drive module 5.2 drives the visual-optical-acoustic-magnetic measurement module 5.5 forward a fixed length along the axial drive axis 5.3. With the cooperation of the visual-optical-acoustic-magnetic measurement module 5.5 and the circumferential drive module 5.4, a scan of the hole perimeter at that depth is completed. Through the coordinated efforts of the visual-optical-acoustic-magnetic measurement module 5.5, the circumferential drive module 5.4, and the axial drive module 5.2, the synchronous acquisition of hole wall surface image information, hole wall surface contour undulation information, shallow hole wall fracture information, and deep hole wall fracture information in the area where the measurement robot is located is completed. The downhole control module 5.6 transmits the hole wall surface image information, hole wall surface contour undulation information, shallow hole wall fracture information, and deep hole wall fracture information in the area where the measurement robot is located, along with the azimuth information acquired by the downhole positioning module 5.7, to the host computer via cable. Simultaneously, the host computer records the depth position information in the cable lowering device.

[0097] After completing the depth measurement task set on the host computer, both the front-end drive module 2 and the back-end drive module 6 retract, and the measurement robot is retrieved through the cable lowering device, thus ending the data acquisition task for this in-situ measurement of deep fracture networks.

[0098] Example 3:

[0099] A method for in-situ measurement of deep fractures using a combined optical, acoustic, and magnetic field (OAM) approach, utilizing the OAM approach for in-situ measurement of deep fractures described in Example 1, mainly includes a data drilling and relocation step, a data feature extraction step, and a fracture network reconstruction step.

[0100] like Figure 10As shown, the data drilling and positioning step utilizes the visual-optical-acoustic-magnetic measurement module 5.5 to simultaneously acquire borehole wall surface image information FD, borehole wall surface contour undulation information LD, borehole wall shallow surface fracture information SD, and borehole wall deep surface fracture information RD; the azimuth information N acquired by the wellbore positioning module 5.7; and the depth position information H acquired by the cable lowering device. The azimuth information and depth position information are synchronized using the geographical azimuth sequence of the borehole from NWSEN (North-West-South-East-North) and the restoration method from depth H1 to depth H2 (shallow to deep). These are represented by matrices FD[ ][ ], LD[ ][ ], SD[ ][ ], and RD[ ][ ]. The storage includes borehole wall surface image information, borehole wall surface contour undulation information, shallow borehole wall crack information, and deep borehole wall crack information. FD[n1][h1] represents the borehole wall surface image information at azimuth n1 and depth h1, which is texture image data. LD[n1][h1] represents the borehole wall surface contour undulation information at azimuth n1 and depth h1, which is point cloud elevation image data. SD[n1][h1] represents the shallow borehole wall crack information at azimuth n1 and depth h1, which is full-pulse acoustic imaging data. RD[n1][h1] represents the deep borehole wall crack information at azimuth n1 and depth h1, which is electromagnetic wave waveform image data.

[0101] like Figure 11 As shown, the data feature extraction step involves using digital image processing to binarize the matrix FD[ ][ ] to form a binary image matrix FFD[ ][ ] containing only cracks (closed continuous regions) and non-cracks (non-closed continuous regions); using digital image processing technology to binarize the borehole wall surface contour undulation information matrix LD[ ][ ] to form a binary image matrix LLD[ ][ ] containing only undulations (closed continuous regions) and non-undulations (non-closed continuous regions); superimposing the elements of the binary image matrix FFD[ ][ ] and the binary image matrix LLD[ ][ ] corresponding to the orientation and depth to form a binary image matrix RH[ ][ ] containing borehole wall surface image and contour undulation information; and calculating the maximum height H[ ][ ]max and minimum height H[ ][ ]min of the crack region in the image region corresponding to each element of the binary image matrix RH[ ][ ] along the borehole center axis direction (image vertical direction).

[0102] like Figure 12As shown, the matrix SD[ ][ ] is binarized using digital image processing technology to form a binary image matrix SSD[ ][ ] containing only cracks (hyperbolic regions) and non-cracks (non-hyperbolic regions). The crack height SHW[ ][ ] of the image region corresponding to the elements of the matrix SD[ ][ ] at each orientation and depth is obtained. The hyperbolic shape is an important indicator for crack identification. If hyperbolic features are present, it can be preliminarily determined that there is a crack at that location. The single-sided curve of the hyperbola usually presents as a semi-arc or a "C"-shaped curve. During detection, the acoustic probe and electromagnetic probe only display one single-sided curve of the hyperbola. The coordinates of the single-sided curve vertex Ssd1 closest to the borehole center axis (SW[ ][ ]1, SH[ ][ ]1) are calculated. SW[ ][ ]1 represents the horizontal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth. SH[ ][ ]1 represents the horizontal coordinate of the single-sided curve vertex Ssd1 at the corresponding orientation and depth. ]1 represents the longitudinal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of the single-sided curve vertex Ssd1; calculate the coordinates of the point Ssd2 ([SW[ ][ ]2,SH[ ][ ]2) on the single-sided curve where the vertex Ssd1 is located, which is farthest from the borehole center axis. SW[ ][ ]2 represents the transverse coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of point Ssd2. SH[ ][ ]2 represents the longitudinal coordinate of the image region corresponding to the element of the matrix SSD[ ][ ] at the corresponding orientation and depth of point Ssd2. Calculate the fracture height SHW[ ][ ] of the image region corresponding to the element of the matrix SSD[ ][ ] at each orientation and depth.

[0103] ;

[0104] Where vs[ ][ ] represents the sound wave propagation speed of the image region corresponding to the elements of the matrix SSD[ ][ ] corresponding to the orientation and depth of the single-sided curve vertex Ssd1.

[0105] like Figure 13As shown, the matrix RD[ ][ ] is binarized using digital image processing to form a binary image matrix RRD[ ][ ] containing only fractures (hyperbolic region) and non-fractures (non-hyperbolic region), thus obtaining the fracture height RHW[ ][ ] of the image region corresponding to the elements of the deep surface fracture information matrix RD[ ][ ] at various orientations and depths; the coordinates (RW[ ][ ]1, RH[ ][ ]1) of the single-sided curve vertex Rrd1 closest to the borehole center axis are calculated, where RW[ ][ ]1 represents the horizontal coordinate of the image region corresponding to the element of the matrix RRD[ ][ ] at the corresponding orientation and depth, and RH[ ][ ]1 represents the vertical coordinate of the image region corresponding to the element of the matrix RRD[ ][ ] at the corresponding orientation and depth; the coordinates ([RW[ ][ ]1, RH[ ][ ]1) of the single-sided curve vertex Rrd1 are calculated, where Rrd2 is the point farthest from the borehole center axis on the single-sided curve where Rrd1 is located are calculated. ]2,RH[ ][ ]2),RW[ ][ ]2 represents the horizontal coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of point Rrd2, and RH[ ][ ]2 represents the vertical coordinate of the image region corresponding to the element of matrix RRD[ ][ ] at the corresponding orientation and depth of point Rrd2. Calculate the crack height RHW[ ][ ] of the image region corresponding to the element of matrix RRD[ ][ ] at each orientation and depth.

[0106] ;

[0107] Where vr[ ][ ] represents the electromagnetic wave propagation speed of the image region corresponding to the elements of the matrix RRD[ ][ ] corresponding to the orientation and depth of the single-sided curve vertex Rrd1.

[0108] like Figure 14 As shown, the fracture network reconstruction steps are as follows:

[0109] This includes: reconstructing the image regions corresponding to the elements of the binary image matrix RH[ ][ ] at various orientations and depths into a borehole wall annular segment with a set thickness in the borehole radial direction; reconstructing the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] in the borehole wall annular segment, specifically: if the maximum height H[ ][ ]max of the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] is 0, it indicates that there are no cracks in the borehole wall, and no cracks are set in the borehole wall annular segment; if the maximum height H[ ][ ]max of the cracks in the image regions corresponding to the elements of the binary image matrix RH[ ][ ] is greater than 0, it indicates that there are cracks in the borehole wall, and cracks are placed at the same height as the cracks in the image regions of the corresponding elements of the binary image matrix RH[ ][ ] in the borehole wall annular segment; at each point on the plane where the height of the cracks is located in the borehole wall annular segment, the height of the cracks is randomly selected from the maximum height H[ ][ ]max to the minimum height H[ ][ ]. The values ​​between ]min, the annular segments corresponding to each azimuth at the same depth are spliced ​​together to form a complete borehole wall annular column, that is, the borehole wall annular column is divided equally by azimuth to form borehole wall annular column segments.

[0110] It also includes: reconstructing the image regions corresponding to the elements of the matrix SSD[ ][ ] at various orientations and depths into near-field annular sections with a set thickness in the borehole radial direction; reconstructing the cracks in the image regions corresponding to the elements of the matrix SSD[ ][ ] within the near-field annular sections, specifically: if the crack height SHW[ ][ ] of the image region corresponding to the elements of the matrix SSD[ ][ ] is 0, it indicates that there are no cracks in the borehole wall, and no cracks are set in the near-field annular section; if the crack height SHW[ ][ ] of the image region corresponding to the elements of the matrix SSD[ ][ ] is greater than 0, it indicates that there are cracks in the borehole wall, and cracks are placed at the same height as the cracks in the image regions of the corresponding elements of the matrix SSD[ ][ ] within the near-field annular section; at each point on the plane where the height of the cracks is located within the near-field annular section, the height of the crack is the crack height SHW[ ][ ]. A crack of fixed height is generated, and the near-field annular segments corresponding to each direction at the same depth are spliced ​​together to form a complete near-field annular segment, that is, the near-field annular segment is formed by dividing the near-field annular segment into equal parts according to the number of directions.

[0111] It also includes: reconstructing the image regions corresponding to the elements of the matrix RRD[ ][ ] at various orientations and depths into far-field annular segments with a set thickness in the borehole radial direction; reconstructing the cracks in the image regions corresponding to the elements of the matrix RRD[ ][ ] in the far-field annular segments, specifically: if the crack height RHW[ ][ ] of the image region corresponding to the elements of the matrix RRD[ ][ ] is 0, it indicates that there are no cracks in the borehole wall, and no cracks are set in the far-field annular segments; if the crack height RHW[ ][ ] of the image region corresponding to the elements of the matrix RRD[ ][ ] is greater than 0, it indicates that there are cracks in the borehole wall, and cracks are placed at the same height as the cracks in the image regions of the corresponding elements of the matrix RRD[ ][ ] in the far-field annular segments; at each point on the plane where the height of the cracks is located in the far-field annular segments, the height of the crack is the crack height RHW[ ][ ]. A crack of fixed height is generated, and the far-field ring column segments corresponding to each direction at the same depth are spliced ​​together to form a complete far-field ring column, that is, the far-field ring column is divided equally by the number of directions to form far-field ring column segments.

[0112] For the reconstructed crack within the borehole wall annular column segment, both the radial and tangential flip axes pass through the center of the crack. The radial and tangential flip axes are located in the same plane and are perpendicular to the central axis of the corresponding borehole wall annular column. The radial flip axis is perpendicular to the central axis of the borehole wall annular column, and the radial flip axis is perpendicular to the tangential flip axis.

[0113] For the reconstructed crack within the near-field annular column segment, both the radial and tangential flip axes pass through the center of the crack. The radial and tangential flip axes are located in the same plane and are perpendicular to the central axis of the corresponding near-field annular column. The radial flip axis is perpendicular to the central axis of the near-field annular column, and the radial flip axis is perpendicular to the tangential flip axis.

[0114] If a crack is present within the current near-field annular segment, the following two steps are performed:

[0115] The first step is to search for cracks in the adjacent borehole wall sections above and below the current near-field borehole section. If a crack is found in one of the borehole wall sections, the crack in the current near-field borehole section is flipped around the tangential flip axis so that the crack in the current near-field borehole section points to the crack in the borehole wall section. The crack in the current near-field borehole section is then superimposed with the fluctuation characteristics of the value between the maximum height H[ ][ ]max and the minimum height H[ ][ ]min based on the corresponding crack height SHW[ ][ ]. If no cracks are found in the adjacent borehole wall sections above and below the same orientation, the crack in the current near-field borehole section is then superimposed with the fluctuation characteristics of the value between the height SHW[ ][ ] / 5 and SHW[ ][ ] / 8 based on the corresponding crack height SHW[ ][ ].

[0116] The second step is to search for cracks in the near-field annular segments above and below the current near-field annular segment. If a crack is found in one of the near-field annular segments above and below the current near-field annular segment, the crack in the current near-field annular segment is flipped around the radial flip axis so that the crack in the current near-field annular segment points to the crack in the searched near-field annular segment.

[0117] For the fracture reconstructed within the far-field annular column segment, both the radial and tangential flip axes pass through the center of the fracture. The radial and tangential flip axes are located in the same plane and are perpendicular to the central axis of the corresponding far-field annular column. The radial flip axis is perpendicular to the central axis of the far-field annular column, and the radial flip axis is perpendicular to the tangential flip axis.

[0118] If a crack is present within the current far-field annular segment, then the following two steps are performed:

[0119] The first step is to search for cracks in the adjacent near-field annular segments at the same orientation as the current far-field annular segment. If a crack is found in one of the near-field annular segments, the crack in the current far-field annular segment is flipped around the tangential flip axis so that the crack in the current far-field annular segment points to the crack in the near-field annular segment. The crack in the current far-field annular segment is then superimposed with the fluctuation characteristics of the value between SHW[ ][ ] / 5 and SHW[ ][ ] / 8 based on the corresponding crack height RHW[ ][ ]. If no cracks are found in the adjacent near-field annular segments at the same orientation, the crack in the current far-field annular segment is not flipped around the tangential flip axis. The crack in the current far-field annular segment is then superimposed with the fluctuation characteristics of the value between RHW[ ][ ] / 5 and RHW[ ][ ] / 8 based on the corresponding crack height RHW[ ][ ].

[0120] The second step is to search for cracks in the adjacent far-field toroidal segments above and below the current far-field toroidal segment. If a crack is found in one of the adjacent far-field toroidal segments above and below the current far-field toroidal segment, the crack in the current far-field toroidal segment is flipped around the radial flip axis so that the crack in the current far-field toroidal segment points to the crack in the searched far-field toroidal segment.

[0121] The above treatments smooth out the cracks in the borehole wall annular section, near-field annular section, and far-field annular section.

[0122] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A deep fracture visual photoacoustic magnetic cooperative in-situ measurement method, using a deep fracture visual photoacoustic magnetic cooperative in-situ measurement device, comprising a measurement robot, the measurement robot comprising a front cylinder and a rear cylinder, the rear end of the front cylinder being sleeved on the front end of the rear cylinder, the front end of the front cylinder being provided with an optical imaging assembly and an acoustic imaging assembly, the front end of the front cylinder being sleeved and fixed with a front end grip air bag (2.2), the front end grip air bag (2.2) being connected with a front end inflation pump (2.1), the front cylinder being further provided with a front central support roller group and a middle central support roller group, the rear cylinder being sleeved and fixed with a rear end grip air bag (6.2), the rear end grip air bag (6.2) being connected with a rear end inflation pump (6.1), the rear cylinder being further provided with a rear central support roller group, a drive fixing module (4.1) being fixed in the front cylinder, the drive fixing module (4.1) being installed with a forward driving module (4.2) for driving the forward driving shaft (4.3) to stretch and retract, the front end face of the rear cylinder being provided with a measurement fixed end face plate (5.1), the measurement fixed end face plate (5.1) being connected with the forward driving shaft (4.3), the measurement fixed end face plate (5.1) being installed with a measurement axial driving module (5.2) for driving the measurement axial driving shaft (5.3) to stretch and retract, the measurement axial driving shaft (5.3) being installed with a measurement circumferential driving module (5.4), the measurement circumferential driving module (5.4) being installed with a visual-light-sound-magnetic measurement module (5.5) and a downhole orientation module (5.7), The visual-light-sound-magnetic measurement module (5.5) contains sensors of various types, including optical cameras for collecting hole wall surface image information, laser probes for collecting hole wall surface profile fluctuation information, sound wave probes for collecting hole wall shallow layer fracture information, and electromagnetic wave probes for collecting hole wall deep layer fracture information, sensors of the same type are uniformly arranged in a circular ring, and the signal detection directions of sensors of different types are perpendicular to the central axis (8), the central axis (8), the central axis of the front cylinder and the central axis of the rear cylinder are collinear, the optical imaging assembly, the acoustic imaging assembly, the front end inflation pump (2.1), the forward driving module (4.2), the measurement axial driving module (5.2), the measurement circumferential driving module (5.4), the visual-light-sound-magnetic measurement module (5.5), and the downhole orientation module (5.7) are connected with the downhole control module (5.6), characterized in that The above method comprises a data borehole homing step: The hole wall surface image information, the hole wall surface profile fluctuation information, the hole wall superficial layer fracture information, and the hole wall deep superficial layer fracture information are stored in matrix FD[ ][ ], matrix LD[ ][ ], matrix SD[ ][ ], and matrix RD[ ][ ] respectively, FD[n1][h1] represents the hole wall surface image information at the azimuth h1 depth of the azimuthal borehole n1, LD[n1][h1] represents the hole wall surface profile fluctuation information at the azimuth h1 depth of the azimuthal borehole n1, SD[n1][h1] represents the hole wall superficial layer fracture information at the azimuth h1 depth of the azimuthal borehole n1, and RD[n1][h1] represents the hole wall deep superficial layer fracture information at the azimuth h1 depth of the azimuthal borehole n1, The matrix FD[ ][ ] is subjected to binaryzation processing to form a binary image matrix FFD[ ][ ]; the matrix LD[ ][ ] is subjected to binaryzation processing to form a binary image matrix LLD[ ][ ]; the elements of the corresponding azimuth and depth of the binary image matrix FFD[ ][ ] and the binary image matrix LLD[ ][ ] are superimposed to form a binary image matrix RH[ ][ ], and the maximum height H[ ][ ]max and the minimum height H[ ][ ]min of the fracture region in the direction along the central axis of the borehole in the binary image matrix RH[ ][ ] are calculated; The matrix SD[ ][ ] is subjected to binaryzation processing to form a binary image matrix SSD[ ][ ], and the coordinates (SW[ ][ ]1, SH[ ][ ]1) of the single curve vertex Ssd1 of the hyperbola closest to the central axis of the borehole are calculated, SW[ ][ ]1 represents the horizontal coordinate of the single curve vertex Ssd1 in the image area corresponding to the element of the corresponding azimuth and depth of the matrix SSD[ ][ ], and SH[ ][ ]1 represents the vertical coordinate of the single curve vertex Ssd1 in the image area corresponding to the element of the corresponding azimuth and depth of the matrix SSD[ ][ ]; the coordinates (SW[ ][ ]2, SH[ ][ ]2) of the point Ssd2 farthest from the central axis of the borehole of the single curve where the single curve vertex Ssd1 is located are calculated, SW[ ][ ]2 represents the horizontal coordinate of the point Ssd2 in the image area corresponding to the element of the corresponding azimuth and depth of the matrix SSD[ ][ ], and SH[ ][ ]2 represents the vertical coordinate of the point Ssd2 in the image area corresponding to the element of the corresponding azimuth and depth of the matrix SSD[ ][ ]; the fracture height SHW[ ][ ] of the image area corresponding to the element of the matrix SSD[ ][ ] of each azimuth and depth is calculated, ； wherein, vs[ ][ ] represents the sound wave propagation speed of the image area corresponding to the element of the matrix SSD[ ][ ] of the corresponding azimuth and depth of the single curve vertex Ssd1. The matrix RD[ ][ ] is binarized to form a binary image matrix RRD[ ][ ], and the coordinates of the single-sided curve vertex Rrd1 of the hyperbola closest to the center axis of the borehole are calculated (RW[ ][ ]1, RH[ ][ ]1), wherein RW[ ][ ]1 represents the horizontal coordinate of the single-sided curve vertex Rrd1 in the image area corresponding to the element of the matrix RRD[ ][ ] at the corresponding azimuth and depth, and RH[ ][ ]1 represents the vertical coordinate of the single-sided curve vertex Rrd1 in the image area corresponding to the element of the matrix RRD[ ][ ] at the corresponding azimuth and depth; the coordinates of the point Rrd2 farthest from the center axis of the borehole on the single-sided curve where the single-sided curve vertex Rrd1 is located are calculated ([RW[ ][ ]2, RH[ ][ ]2), wherein RW[ ][ ]2 represents the horizontal coordinate of the point Rrd2 in the image area corresponding to the element of the matrix RRD[ ][ ] at the corresponding azimuth and depth, and RH[ ][ ]2 represents the vertical coordinate of the point Rrd2 in the image area corresponding to the element of the matrix RRD[ ][ ] at the corresponding azimuth and depth, and the fracture height RHW[ ][ ] of the image area corresponding to the element of the matrix RRD[ ][ ] at each azimuth and depth is calculated, ； wherein vr[ ][ ] represents the electromagnetic wave propagation speed of the image area corresponding to the element of the binary image matrix RRD[ ][ ] at the corresponding azimuth and depth of the single-sided curve vertex Rrd1, Further comprising a fracture network reconstruction step, which comprises: reconstructing the image area corresponding to the element of the binary image matrix RH[ ][ ] at each azimuth and depth into a borehole wall ring cylinder segment with a set thickness in the radial direction of the borehole, and reconstructing the fracture of the image area corresponding to the element of the binary image matrix RH[ ][ ] into the borehole wall ring cylinder segment, specifically: if the maximum height H[ ][ ]max of the fracture of the image area corresponding to the element of the binary image matrix RH[ ][ ] is 0, no fracture is arranged in the borehole wall ring cylinder segment; if the maximum height H[ ][ ]max of the fracture of the image area corresponding to the element of the binary image matrix RH[ ][ ] is greater than 0, a fracture is arranged at the same height as the fracture of the image area corresponding to the element of the binary image matrix RH[ ][ ] in the borehole wall ring cylinder segment, and at each point on the plane where the height of the arranged fracture is located in the borehole wall ring cylinder segment, the height of the fracture is randomly selected to be a value between the maximum height H[ ][ ]max and the minimum height H[ ][ ]min, and the ring cylinder segments corresponding to each azimuth at the same depth are spliced into a complete borehole wall ring, i.e., the borehole wall ring is equally divided by the number of azimuths to form the borehole wall ring cylinder segments, Further comprising: reconstructing the image area corresponding to the element of the matrix SSD[ ][ ] of each orientation and depth into a near-field ring cylinder segment with a set thickness in the radial direction of the borehole, reconstructing the fracture of the image area corresponding to the element of the matrix SSD[ ][ ] in the near-field ring cylinder segment, specifically: if the fracture height SHW[ ][ ] of the image area corresponding to the element of the matrix SSD[ ][ ] is 0, no fracture is arranged in the near-field ring cylinder segment; if the fracture height SHW[ ][ ] of the image area corresponding to the element of the matrix SSD[ ][ ] is greater than 0, a fracture is arranged at the same height of the fracture of the image area corresponding to the element of the matrix SSD[ ][ ] in the near-field ring cylinder segment, at each point on the plane where the height of the arranged fracture in the near-field ring cylinder segment is located, the height of the fracture is the fracture height SHW[ ][ ], a fracture with a fixed height is generated, the near-field ring cylinder segments corresponding to each orientation at the same depth are spliced into a complete near-field ring cylinder, that is, the near-field ring cylinder is equally divided by the number of orientations to form the near-field ring cylinder segment, Further comprising: reconstructing the image area corresponding to the element of the matrix RRD[ ][ ] of each orientation and depth into a far-field ring cylinder segment with a set thickness in the radial direction of the borehole, reconstructing the fracture of the image area corresponding to the element of the matrix RRD[ ][ ] in the far-field ring cylinder segment, specifically: if the fracture height RHW[ ][ ] of the image area corresponding to the element of the matrix RRD[ ][ ] is 0, no fracture is arranged in the far-field ring cylinder segment; if the fracture height RHW[ ][ ] of the image area corresponding to the element of the matrix RRD[ ][ ] is greater than 0, a fracture is arranged at the same height of the fracture of the image area corresponding to the element of the matrix RRD[ ][ ] in the far-field ring cylinder segment, at each point on the plane where the height of the arranged fracture in the far-field ring cylinder segment is located, the height of the fracture is the fracture height RHW[ ][ ], a fracture with a fixed height is generated, the far-field ring cylinder segments corresponding to each orientation at the same depth are spliced into a complete far-field ring cylinder, that is, the far-field ring cylinder is equally divided by the number of orientations to form the far-field ring cylinder segment, Further comprising the following steps: For the fracture reconstructed in the near-field ring cylinder segment, the radial flip axis and the tangential flip axis both pass through the center of the fracture, the radial flip axis and the tangential flip axis are located in the same plane and are perpendicular to the central axis of the corresponding near-field ring cylinder, the radial flip axis is perpendicular to the central axis of the near-field ring cylinder, and the radial flip axis is perpendicular to the tangential flip axis, If a fracture is arranged in the current near-field ring cylinder segment, the following two steps are performed: The first step: then search for the crack in the upper and lower adjacent hole wall cylinder segments in the same orientation of the current near-field cylinder segment, if one of the hole wall cylinder segments has a crack, then flip the crack in the current near-field cylinder segment around the tangential flip axis, so that the crack in the current near-field cylinder segment points to the crack in the hole wall cylinder segment, and add the fluctuation feature with a height between the maximum height H[][] max and the minimum height H[][] min to the crack in the current near-field cylinder segment based on the corresponding crack height SHW[][], The second step: then search for the crack in the upper and lower adjacent near-field cylinder segments in the previous orientation of the current near-field cylinder segment, if one of the near-field cylinder segments in the previous orientation has a crack, then flip the crack in the current near-field cylinder segment around the radial flip axis, so that the crack in the current near-field cylinder segment points to the crack in the searched near-field cylinder segment, Further comprising the following steps: For the reconstructed crack in the far-field cylinder segment, the radial flip axis and the tangential flip axis pass through the center of the crack, the radial flip axis and the tangential flip axis are located in the same plane and are perpendicular to the central axis of the corresponding far-field cylinder, the radial flip axis is perpendicular to the central axis of the far-field cylinder, and the radial flip axis is perpendicular to the tangential flip axis, If the current far-field cylinder segment has a crack, then perform the following two steps: The first step: then search for the crack in the upper and lower adjacent near-field cylinder segments in the same orientation of the current far-field cylinder segment, if one of the near-field cylinder segments has a crack, then flip the crack in the current far-field cylinder segment around the tangential flip axis, so that the crack in the current far-field cylinder segment points to the crack in the near-field cylinder segment, and add the fluctuation feature with a height between SHW[][] / 5 and SHW[][] / 8 to the crack in the current far-field cylinder segment based on the corresponding crack height RHW[][]; if the upper and lower adjacent near-field cylinder segments in the same orientation do not have cracks, then do not flip the crack in the current far-field cylinder segment around the tangential flip axis, and add the fluctuation feature with a height between RHW[][] / 5 and RHW[][] / 8 to the crack in the current far-field cylinder segment based on the corresponding crack height RHW[][], The second step: search for the crack in the upper and lower adjacent far-field cylinder segments in the previous orientation of the current far-field cylinder segment, if one of the far-field cylinder segments in the previous orientation has a crack, then flip the crack in the current far-field cylinder segment around the radial flip axis, so that the crack in the current far-field cylinder segment points to the crack in the searched far-field cylinder segment.

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