A method and device for long-range acoustic detection of horizontal boreholes with directional identification capabilities

Abstract

This invention discloses a method and device for long-range acoustic detection in horizontal boreholes, capable of identifying azimuth, relating to the field of long-range acoustic detection. The method includes controlling an acoustic transmitting module to emit acoustic signals; controlling an acoustic receiving module to receive the returned acoustic signals and obtaining the acoustic azimuth angle using a gyroscope; obtaining azimuth reflected wave signals based on the returned acoustic signals and the azimuth angle; and processing the azimuth reflected wave signals to obtain an azimuth imaging profile. The long-range acoustic detection method for horizontal boreholes provided by this invention can achieve directional detection with high accuracy.

Description

Technical Field

[0001] This invention relates to the field of acoustic long-range detection, specifically to a method and device for acoustic long-range detection of horizontal boreholes that can distinguish directions. Background Technology

[0002] Acoustic wave detection technology, as an important geophysical exploration method, has played a crucial role in fields such as deep underground space exploration, engineering geological surveys, and mineral resource exploration. However, with the increasing prevalence of horizontal borehole exploration scenarios (such as underground utility tunnel exploration, horizontal vein detection, and tunnel advanced geological prediction), existing acoustic wave detection technologies still face many challenges in adapting to horizontal borehole conditions and achieving accurate azimuth identification.

[0003] First, the borehole diameter in engineering exploration is typically smaller than that of oil and gas exploration boreholes (deep boreholes are generally 75mm in diameter). This necessitates that acoustic detection equipment achieve a high acoustic emission power within limited volume constraints, resulting in a significant "small volume - high power" design contradiction. Currently used high-power in-hole acoustic detection equipment is mostly designed for large-diameter oil and gas exploration boreholes, making it difficult to directly adapt to the confined space of horizontal engineering exploration boreholes. Furthermore, engineering exploration demands a much higher level of precision in detecting underground structures than oil and gas exploration, and the integration of equipment within confined spaces is challenging, further exacerbating the technical difficulties of acoustic detection in horizontal borehole scenarios.

[0004] Secondly, existing acoustic detection equipment struggles to acquire directional information about target geological bodies. Most existing equipment uses omnidirectional transmission modules, where sound waves propagate spherically outside the borehole. The receiving module can only capture the intensity of the reflected sound waves, failing to accurately correlate the spatial orientation of the reflected signal. When drilling horizontally to detect targets such as faults, fissures, or ore body boundaries, while the presence of the target can be preliminarily identified, its direction of extension, spatial distribution, and relative orientation to the borehole cannot be accurately determined. Especially under complex geological conditions, this lack of directional information easily leads to misjudgment or omission of geological bodies, failing to provide accurate geological basis for engineering design and construction.

[0005] Furthermore, traditional acoustic detection equipment generally adopts a separate structural design, with the main unit and probe connected by a cable, and often relies on gravity to move and position the probe in vertical holes. While this structure meets the requirements for use in vertical boreholes, it faces several unavoidable challenges in horizontal borehole detection: Firstly, in horizontal boreholes, the probe cannot move autonomously by gravity, requiring additional complex external propulsion devices, which not only increases equipment deployment costs but also makes it prone to friction and collision with the borehole wall, affecting detection stability; secondly, long-distance cable transmission leads to severe attenuation of acoustic signals, reducing detection accuracy and data reliability; more importantly, in horizontal borehole measurement-while-drilling scenarios, the acoustic equipment needs to be integrated inside the drill pipe, and the strict constraints of the drill pipe diameter further limit the equipment size, directly affecting detection resolution and detection range.

[0006] Therefore, current horizontal borehole acoustic remote detection technology suffers from poor detection accuracy and cannot meet the detection needs under complex geological conditions. Summary of the Invention

[0007] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a method and device for long-range acoustic detection of horizontal boreholes that can distinguish directions, thereby solving the technical problem of poor detection accuracy in the prior art.

[0008] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a method for long-range acoustic detection of horizontal boreholes with identifiable azimuth. The method includes controlling an acoustic wave transmitting module to emit an acoustic wave signal; controlling an acoustic wave receiving module to receive the returned acoustic wave signal and obtaining the azimuth angle of the acoustic wave through a gyroscope; obtaining an azimuth reflection wave signal based on the returned acoustic wave signal and the azimuth angle of the acoustic wave; and processing the azimuth reflection wave signal to obtain an azimuth imaging profile.

[0010] In some embodiments, processing the azimuth reflected wave signal to obtain an azimuth imaging profile includes: performing a Fourier transform on the azimuth reflected wave signal to obtain an azimuth constraint function; and using an azimuth imaging algorithm based on the azimuth constraint function to obtain the azimuth imaging profile.

[0011] In some embodiments, obtaining the azimuth reflected wave signal based on the returned acoustic wave signal and the acoustic wave azimuth angle includes: obtaining the wave field component based on the returned acoustic wave signal and the acoustic wave azimuth angle. ,in Represents three-dimensional spatial coordinates. Indicates time, The azimuth angle of the sound wave is represented; the azimuth reflected wave signal is obtained after processing based on the slow scan function. ;

[0012] ;

[0013] ;

[0014] ;

[0015] in Indicates frequency, Represents the space wavenumber. Indicates the sound wave velocity in the medium. This represents a slow scan function.

[0016] In some embodiments, performing a Fourier transform on the azimuth reflection signal to obtain the azimuth constraint function includes: performing a Fourier transform on the azimuth reflection signal:

[0017] ;

[0018] ;

[0019] in, and Let represent the azimuth constraint function; if imaging is performed using reflected waves, then... ;

[0020] The azimuth imaging profile obtained by using the azimuth constraint function and azimuth imaging algorithm includes:

[0021] ;

[0022] ;

[0023] in, This indicates an azimuth filter.

[0024] Secondly, the present invention also provides a horizontal borehole acoustic long-range detection device capable of identifying orientation, comprising a housing, an acoustic wave emitting module, an acoustic wave receiving module, a gyroscope, and a main control module. The housing has a receiving cavity; the acoustic wave emitting module is located in the receiving cavity for emitting acoustic wave signals; the acoustic wave receiving module is located in the receiving cavity for receiving returned acoustic wave signals; the gyroscope is located in the receiving cavity for recording the azimuth angle of the acoustic waves; and the main control module is located in the receiving cavity and is signal-connected to the acoustic wave emitting module and the acoustic wave receiving module.

[0025] In some embodiments, the horizontal borehole acoustic remote detection device further includes a sound insulation body located between the acoustic wave transmitting module and the acoustic wave receiving module.

[0026] In some embodiments, the acoustic wave emitting module employs a low-frequency electric spark source, with the low-frequency range being 50Hz-2000Hz.

[0027] In some embodiments, the acoustic wave receiving module includes a patch-type three-component sensor for recording acoustic wave signals from different directions.

[0028] In some embodiments, the horizontal drilling acoustic remote detection device further includes a rubber anti-collision head, which is located at the front end of the horizontal drilling acoustic remote detection device in the direction of travel.

[0029] In some embodiments, the horizontal drilling acoustic remote detection device further includes a battery module located within a receiving cavity, at the end of the horizontal drilling acoustic remote detection device in the direction of travel.

[0030] Compared with existing technologies, the present invention provides a horizontal borehole acoustic long-range detection method that can identify the orientation. This method can accurately bind the acoustic signal and the acoustic azimuth angle to determine the spatial orientation of the target geological body. The two information are combined and processed to obtain the azimuth reflection wave signal. The azimuth imaging profile is obtained by processing the azimuth reflection wave signal, thereby effectively improving the detection accuracy. It is especially suitable for detection under complex geological conditions. Attached Figure Description

[0031] Figure 1 This is a schematic flowchart of a horizontal borehole acoustic remote detection method provided in an embodiment of the present invention;

[0032] Figure 2 This is a schematic flowchart of another horizontal borehole acoustic remote detection method provided in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the structure of a horizontal borehole acoustic remote detection device provided in an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 100. Horizontal borehole acoustic long-range detection method;

[0036] 200. Horizontal borehole acoustic detection device;

[0037] 210. Housing; 220. Acoustic wave transmitting module; 230. Acoustic wave receiving module; 231. Surface mount three-component sensor; 240. Gyroscope; 250. Main control module; 260. Sound insulation body; 270. Rubber anti-collision head; 280. Battery module; 290. Storage module. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] As an important geophysical exploration method, acoustic wave detection technology has played a key role in fields such as deep underground space exploration, engineering geological surveys, and mineral resource exploration.

[0040] Current horizontal borehole acoustic remote detection technology suffers from poor detection accuracy and cannot meet the detection needs under complex geological conditions.

[0041] To address the technical problem of poor detection accuracy in existing technologies, this invention provides a method and device for long-range acoustic detection of horizontal boreholes that can distinguish directions. The method for long-range acoustic detection of horizontal boreholes provided by this invention can achieve directional detection with high accuracy.

[0042] It should be noted that the horizontal borehole acoustic remote detection method of the present invention is used for, but not limited to, underground utility tunnel exploration. For ease of explanation, this invention will only use the application of the horizontal borehole acoustic remote detection method to underground utility tunnel exploration as an example. The principle of the horizontal borehole acoustic remote detection method applied to other horizontal borehole exploration scenarios is essentially the same as that applied to underground utility tunnel exploration, and will not be elaborated here.

[0043] This application provides a method 100 for long-range acoustic detection of horizontal boreholes that can distinguish orientation, such as... Figure 1 As shown, the horizontal borehole acoustic remote detection method 100 includes:

[0044] Step S110: Control the sound wave emitting module to emit a sound wave signal.

[0045] Specifically, the main control module in the horizontal borehole acoustic remote detection device controls the acoustic wave transmitting module to transmit high-energy low-frequency acoustic wave signals through optical fiber communication.

[0046] Step S120: Control the sound wave receiving module to receive the returned sound wave signal and obtain the sound wave azimuth angle through the gyroscope.

[0047] Specifically, after the acoustic wave transmitting module emits an acoustic wave signal, the acoustic wave propagates in the strata outside the borehole, is reflected back by the geological body outside the borehole, and is received by the acoustic wave receiving module. At the same time, the gyroscope records the azimuth angle of the acoustic wave.

[0048] Step S130: Based on the returned acoustic wave signal and the acoustic wave azimuth angle, obtain the azimuth reflection wave signal.

[0049] Specifically, after obtaining the returned sound wave signal and sound wave azimuth angle, the main control module processes the sound wave signal and sound wave azimuth angle to obtain the azimuth reflection wave signal.

[0050] Step S140: Process the azimuth reflected wave signal to obtain the azimuth imaging profile.

[0051] Specifically, after obtaining the azimuth reflected wave signal, the main control module processes the azimuth reflected wave signal to obtain the azimuth reflected wave signal itself. All data can be transmitted to the storage module for storage via fiber optic communication.

[0052] In this embodiment, the method can accurately bind the acoustic signal and the azimuth angle to determine the spatial orientation of the target geological body. The two information are combined and processed to obtain the azimuth reflection wave signal. The azimuth imaging profile is obtained by processing the azimuth reflection wave signal, thereby effectively improving the detection accuracy. It is especially suitable for detection under complex geological conditions.

[0053] In some embodiments, such as Figure 2 As shown, step S140 involves processing the azimuth reflected wave signal to obtain an azimuth imaging profile, including:

[0054] Step S141: Perform a Fourier transform on the azimuth reflected wave signal to obtain the azimuth constraint function.

[0055] Step S142: Obtain the azimuth imaging profile by using the azimuth constraint function and the azimuth imaging algorithm.

[0056] In some embodiments, such as Figure 2 As shown, step S130, based on the returned acoustic wave signal and the acoustic wave azimuth angle, obtains the azimuth reflected wave signal, including:

[0057] Step S131: Extraction of azimuth reflection waves based on slow scanning.

[0058] The wave field components are obtained based on the returned sound wave signal and the sound wave azimuth angle. ,in Represents three-dimensional spatial coordinates. Indicates time, This represents the azimuth angle of the sound wave, i.e., the angle recorded by the gyroscope from the sound wave sensor. The azimuth reflected wave signal can be obtained using the following formula. .

[0059] ;

[0060] ;

[0061] ;

[0062] in Indicates frequency, Represents the space wavenumber. Indicates the sound wave velocity in the medium. This represents the slow scanning function. It should be noted that the azimuth reflection wave extraction algorithm based on slow scanning achieves directional extraction of reflected waves. Compared to omnidirectional reflected waves, the processed reflected waves have a specified azimuth enhancement characteristic, improving the signal-to-noise ratio of reflected waves in a specified direction.

[0063] After step S130 is completed, step S140 is performed for azimuth imaging. Step S140 specifically includes steps S141 and S142.

[0064] Step S141: Perform a Fourier transform on the azimuth reflected wave signal to obtain the azimuth constraint function, including:

[0065] ;

[0066] ;

[0067] in, and This represents the azimuth constraint function. It should be noted that when using reflected waves for imaging, only the up-traveling wave is considered. .

[0068] Step S142, obtaining the azimuth imaging profile based on the azimuth constraint function using the azimuth imaging algorithm includes: after inverse Fourier transform,

[0069] ;

[0070] After Fourier transform and dispersion relation transformation, the imaging profile can be obtained. :

[0071] ;

[0072] in, This refers to an azimuth filter. It can increase the reflected wave energy at a specified azimuth. Applying the above method, profiles corresponding to different azimuths can be obtained, thereby achieving azimuth identification of geological anomalies outside the borehole. It should be noted that using an azimuth imaging algorithm, focusing on the reflected wave energy at a specified azimuth, results in high imaging accuracy and small azimuth identification error.

[0073] This application embodiment also provides a horizontal borehole acoustic remote detection device 200 capable of distinguishing orientation, such as... Figure 3As shown, the horizontal drilling acoustic detection device 200 includes a housing 210, an acoustic emitting module 220, an acoustic receiving module 230, a gyroscope 240, and a main control module 250. The housing 210 has a receiving cavity; the acoustic emitting module 220 is located in the receiving cavity and is used to emit acoustic signals; the acoustic receiving module 230 is located in the receiving cavity and is used to receive the returned acoustic signals; the gyroscope 240 is located in the receiving cavity and is used to record the azimuth angle of the acoustic waves; the main control module 250 is located in the receiving cavity and is signal-connected to the acoustic emitting module 220 and the acoustic receiving module 230.

[0074] The housing 210 is the outer shell structure of the horizontal borehole acoustic remote detection device 200, used to accommodate various functional modules for detection needs. The size of the housing 210 can be determined according to actual needs, as long as it meets the requirements of the exploration borehole diameter.

[0075] The acoustic wave transmitting module 220 is the signal transmitting unit of the device. According to the instructions of the main control module 250, it transmits high-energy, low-frequency acoustic wave signals to meet the energy requirements for stratum penetration. The low-frequency acoustic wave has strong stratum penetration capability and can effectively propagate over long distances in the strata outside the borehole, reach deep geological bodies and form reflections.

[0076] For example, the acoustic wave emitting module 220 uses a low-frequency electric spark source, with a low-frequency range of 50Hz-2000Hz. By using a small-volume, high-power low-frequency electric spark source, the acoustic wave emitting module 220 ensures both signal energy and acoustic wave penetration capability.

[0077] The acoustic wave receiving module 230 is the signal acquisition unit of the device, which accurately receives high-energy low-frequency acoustic wave signals reflected back from the strata outside the borehole.

[0078] For example, the acoustic wave receiving module 230 includes a patch-type three-component sensor 231, which is used to record acoustic wave signals from different directions. By adopting a three-component design, acoustic wave signals from different directions and dimensions can be acquired simultaneously, achieving omnidirectional signal coverage and significantly improving the comprehensiveness of detection. Furthermore, the patch-type sensor has the dual advantages of high receiving accuracy and miniaturization, ensuring the accuracy of acoustic wave signal acquisition while adapting to the installation requirements of the device.

[0079] The gyroscope 240 is a high-precision orientation sensing unit for the device, used to record the spatial orientation and angle information of the device in real time and to achieve precise synchronization with the sound wave receiving module; it realizes one-to-one correspondence calibration between sound wave signals and orientation angles, and achieves accurate sound wave orientation detection.

[0080] The main control module 250 is the central control unit of the device, undertaking functions such as overall scheduling, command issuance, data processing, and synchronization coordination. The main control module 250 issues sound wave transmission commands to the sound wave transmitting module 220 to precisely control the working timing of the low-frequency electric spark source; the main control module 250 coordinates the synchronous operation of the sound wave receiving module 230 and the gyroscope 240 to ensure the synchronization of sound wave signal acquisition and azimuth angle recording; the main control module 250 performs preliminary processing on the received raw sound wave signals, completes the binding of signals and azimuth data, and can obtain imaging profiles through calculation and processing.

[0081] For example, the horizontal borehole acoustic remote detection device 200 also includes a storage module 290, which is equipped with a large-capacity internal storage card and is responsible for receiving and saving acoustic signal data, gyroscope azimuth angle data, synchronization calibration data, etc. transmitted by the main control module 250; with a large-capacity design, it can realize long-term cableless data acquisition.

[0082] In some embodiments, the horizontal borehole acoustic remote detection device 200 further includes a sound insulation body 260, which is located between the acoustic wave transmitting module 220 and the acoustic wave receiving module 230.

[0083] In this embodiment, the sound insulation element 260 is a dedicated acoustic functional component located between the sound wave emitting module 220 and the sound wave receiving module 230. It ensures the accuracy of the detection data by attenuating direct sound transmission and constructing an acoustic isolation zone. For example, it can be made of high-damping, high-density materials with excellent sound insulation performance (such as composite damping materials or integrated sound-absorbing and sound-insulating materials). The sound insulation element 260 has the following advantages: 1. It isolates direct sound interference, significantly attenuates invalid sound wave transmission, prevents strong direct sound from masking the effective signals reflected from the strata, and ensures that the sound wave receiving module 230 only collects the target detection signal. 2. It ensures detection accuracy, eliminates signal misjudgment caused by direct sound, and achieves precise binding between the reflected sound wave signal and the gyroscope's orientation from the source, avoiding deviations in geological body orientation analysis. 3. It adapts to the compact layout requirements of the device, forming an acoustic isolation zone between adjacent sound wave emitting modules 220 and sound wave receiving modules 230, completing the acoustic zoning of the device, and achieving physical adjacency and complete acoustic isolation.

[0084] In some embodiments, such as Figure 3 As shown, the horizontal drilling acoustic remote detection device 200 also includes a rubber anti-collision head 270, which is located at the front end of the horizontal drilling acoustic remote detection device 200 in the direction of travel.

[0085] In this embodiment, the rubber anti-collision head 270 is a protective unit of the device. The rubber anti-collision head 270 is made of high-density rubber material. During the operation of the device being pushed by the drilling rig, it can buffer the friction and impact between the device and the borehole wall, avoid damage to the device housing 210 and internal functional modules due to impact, and ensure the structural integrity of the device and the reliability of the detection operation.

[0086] In some embodiments, such as Figure 3 As shown, the horizontal drilling acoustic remote detection device 200 also includes a battery module 280 located in the receiving cavity, at the end of the horizontal drilling acoustic remote detection device 200 in the direction of travel.

[0087] In this embodiment, the battery module 280 is the power source of the device. Its high-power internal battery provides continuous and stable power, fully meeting the power requirements of all units, including the acoustic wave transmitting module 220, acoustic wave receiving module 230, gyroscope 240, and main control module 250. The battery module 280 is positioned at the end of the horizontal drilling acoustic wave remote detection device 200's travel direction, away from high-risk collision areas at the front, reducing the risk of battery impact damage and ensuring power supply safety. Furthermore, its location at the end facilitates battery replacement, improving the ease of battery replacement for the horizontal drilling acoustic wave remote detection device 200.

[0088] In some embodiments, such as Figure 3 As shown, the horizontal drilling acoustic remote detection device 200 includes multiple functional modules. From the front end to the back end in the direction of travel, the horizontal drilling acoustic remote detection device 200 consists of: a rubber anti-collision head 270, an acoustic wave emitting module 220, a sound insulation body 260, an acoustic wave receiving module 230, a main control module 250, a gyroscope 240, a storage module 290, and a battery module 280.

[0089] The detection principle of the horizontal borehole acoustic detection device 200 is as follows:

[0090] The main control module 250 controls the acoustic wave transmitting module 220 to transmit high-energy low-frequency acoustic wave signals via fiber optic communication. The acoustic waves propagate in the strata outside the borehole, are reflected back by the surrounding geological formation, and are received by the acoustic wave receiving module 230. The main control module 250, via fiber optic communication, controls the patch-type three-component sensor 231 in the acoustic wave receiving module 230 to synchronize with the gyroscope 240, and records the acoustic wave signal and azimuth angle at that moment. The main control module 250 processes the acoustic signal and azimuth angle to obtain the imaging profile. All data is transmitted to the storage module 290 via fiber optic communication. This horizontal borehole acoustic remote detection device 200 can achieve omnidirectional emission and directional reception of acoustic waves, thus achieving directional detection. Furthermore, the use of fiber optic communication technology effectively overcomes the problem of strong electromagnetic interference, enabling high-fidelity acquisition of the entire tensor wave field.

[0091] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for long-range acoustic detection of horizontal boreholes capable of identifying orientation, characterized in that, include: Control the acoustic wave transmitting module to emit acoustic wave signals; The control sound wave receiving module receives the returned sound wave signal and obtains the sound wave azimuth angle through the gyroscope; Based on the returned acoustic wave signal and the acoustic wave azimuth angle, the azimuth reflected wave signal is obtained, including obtaining the wave field component based on the returned acoustic wave signal and the acoustic wave azimuth angle. ,in Represents three-dimensional spatial coordinates. Indicates time, Indicates the azimuth angle of the sound wave; The azimuth reflection signal is obtained after processing with the slow scan function. ; ； ； ； in Indicates frequency, Represents the space wavenumber. Indicates the sound wave velocity in the medium. This represents the slow scan function. Represents the imaginary unit; The azimuth reflected wave signal is processed to obtain an azimuth imaging profile, including performing a Fourier transform on the azimuth reflected wave signal to obtain an azimuth constraint function; An azimuth imaging profile is obtained using an azimuth imaging algorithm based on the aforementioned azimuth constraint function.

2. The horizontal borehole acoustic long-range detection method according to claim 1, characterized in that, The Fourier transform of the azimuth reflected wave signal to obtain the azimuth constraint function includes: Perform a Fourier transform on the azimuth reflected wave signal: ； ； in, and Let represent the azimuth constraint function; if imaging is performed using reflected waves, then... ; The process of obtaining the azimuth imaging profile based on the azimuth constraint function using the azimuth imaging algorithm includes: ； ； in, This indicates an azimuth filter. Represents the imaginary unit. It represents angular frequency.

3. A horizontal borehole acoustic long-range detection device capable of identifying orientation, applied to the horizontal borehole acoustic long-range detection method described in claim 1 or 2, characterized in that, include: The shell has a receiving cavity; A sound wave emitting module, located within the receiving cavity, is used to emit sound wave signals; An acoustic wave receiving module, located within the accommodating cavity, is used to receive returned acoustic wave signals; A gyroscope, located within the cavity, is used to record the azimuth angle of sound waves; The main control module is located inside the cavity and is signal-connected to the acoustic wave transmitting module and the acoustic wave receiving module.

4. The horizontal borehole acoustic long-range detection device according to claim 3, characterized in that, It also includes a sound insulation element, which is located between the sound wave transmitting module and the sound wave receiving module.

5. The horizontal borehole acoustic long-range detection device according to claim 4, characterized in that, The acoustic wave emitting module uses a low-frequency electric spark source, and the low frequency range is 50Hz-2000Hz.

6. The horizontal borehole acoustic long-range detection device according to claim 4, characterized in that, The acoustic wave receiving module includes a patch-type three-component sensor, which is used to record acoustic wave signals from different directions.

7. The horizontal borehole acoustic long-range detection device according to claim 3, characterized in that, It also includes a rubber anti-collision head, which is located at the front end of the horizontal drilling acoustic remote detection device in the direction of travel.

8. The horizontal borehole acoustic long-range detection device according to claim 3, characterized in that, It also includes a battery module located within the receiving cavity, at the end of the direction of travel of the horizontal drilling acoustic remote detection device.

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