Urban pipeline detection device and method based on controllable seismic source

Abstract

The invention belongs to the technical field of urban underground pipeline detection, and provides an urban pipeline detection device and method based on a controllable seismic source, the device comprises the controllable seismic source, a multichannel receiving array and a processing terminal, the controllable seismic source comprises a hydraulic pump, the bottom of the hydraulic pump is connected with a vibration head, the hydraulic pump is controlled by a controllable driving module, and the multichannel receiving array is connected with the processing terminal. The excitation energy, frequency and / or waveform of the vibration head are / is changed; the multi-channel receiving array comprises a plurality of detectors which are arranged at intervals, the arrangement mode is determined according to a detection task requirement, and the multi-channel receiving array is used for acquiring a seismic source trigger signal and a detection signal; and the processing terminal is used for performing adaptive filtering, reflected wave feature extraction and three-dimensional imaging on the seismic source trigger signal and the detection signal to obtain a pipeline imaging result. According to the invention, high-precision and high-efficiency detection of underground pipelines made of various materials is realized, and an advanced technical means is provided for fine management of urban underground space.

Description

Technical Field

[0001] This invention belongs to the field of urban underground pipeline detection technology, specifically relating to an urban pipeline detection device and method based on a controllable seismic source. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] As a core component of urban infrastructure, the accurate detection of urban underground pipelines is of great significance for pipeline maintenance, emergency repair, and urban planning. However, the detection technologies currently used have many limitations and cannot meet the needs of accurate detection in the complex environment of modern cities.

[0004] Pipeline locator technology is based on the principle of electromagnetic induction, locating pipelines by applying an electric current signal to metal pipes and receiving the induced magnetic field on the ground. While this technology has certain advantages in detecting metal pipelines, it is completely ineffective for non-metallic pipelines, and its detection depth is severely limited to a range of 3 to 5 meters. In urban environments, due to strong electromagnetic interference, the false alarm rate of this technology can be as high as 30%, seriously affecting the reliability of detection. Especially near substations, subways, and high-power electrical equipment, the complex distribution of electromagnetic fields makes traditional pipeline locators almost impossible to operate normally, resulting in detection blind spots.

[0005] Ground-penetrating radar (GPR) technology utilizes the reflection characteristics of electromagnetic waves in underground media for pipeline detection, theoretically offering good resolution and detection depth. However, in practical applications, this technology faces numerous challenges. When the stratum has high water content or the soil has high conductivity, the electromagnetic wave signal attenuates severely, significantly reducing detection effectiveness. Particularly for small-diameter pipes less than 50 mm, the technology's identification rate is only around 60%, failing to meet the requirements for precision pipeline detection. Furthermore, GPR is susceptible to interference from metal structures and electronic equipment in complex urban environments, leading to false echoes and signal distortion. More seriously, in soil environments with high salinity, the propagation distance of electromagnetic waves is drastically reduced, severely limiting the technology's application in coastal cities.

[0006] While traditional seismic wave detection methods possess theoretical advantages such as strong penetration and wide applicability to various materials, they suffer from serious shortcomings in practical applications. The excitation energy of artificially struck seismic sources is inconsistent, with frequency fluctuations reaching up to 30%, leading to highly unstable responses to pipelines at different burial depths. Shallow pipelines are prone to signal saturation distortion, while deep pipelines exhibit weak signals and low signal-to-noise ratios, making effective identification difficult. Explosive seismic sources, although possessing high energy, pose safety hazards in urban environments, and single-frequency excitation cannot be optimized for pipelines of different diameters. Pipeline detection in urban environments also faces severe noise interference problems. These challenges severely restrict the application of traditional seismic wave detection in urban settings.

[0007] Furthermore, existing technologies generally lack real-time processing capabilities, relying mostly on post-processing data, which typically takes hours or even days. This makes it impossible to provide rapid detection results on-site, severely impacting work efficiency. In scenarios with extremely high time requirements, such as emergency repairs, the lag in traditional technologies becomes a major constraint. When critical pipelines such as urban water and gas supply experience sudden failures, rapid and accurate pipeline location is directly related to the speed of troubleshooting and urban safety; the limitations of traditional technologies are particularly evident in such emergency situations. Summary of the Invention

[0008] To address the aforementioned problems, this invention proposes an urban pipeline detection device and method based on a controllable seismic source. This invention integrates controllable excitation, array reception, intelligent processing, and real-time imaging, solving key technical bottlenecks in existing technologies regarding seismic source control, noise suppression, material adaptability, and real-time performance, and providing strong technical support for the refined management of urban underground space.

[0009] According to some embodiments, the present invention adopts the following technical solution: A controllable seismic source-based urban pipeline detection device includes a controllable seismic source, a multi-channel receiving array, and a processing terminal, wherein: The controllable vibration source includes a hydraulic pump, the bottom of which is connected to a vibrating head. The hydraulic pump is controlled by a controllable drive module to change the energy, frequency, and / or waveform excited by the vibrating head. The multi-channel receiving array includes multiple detectors spaced apart, the arrangement of which is determined according to the requirements of the detection mission, and is used to acquire the source trigger signal and the detection signal; The processing terminal is used to perform adaptive filtering, reflected wave feature extraction, and three-dimensional imaging on the seismic source trigger signal and detection signal to obtain pipeline imaging results.

[0010] As an alternative implementation, the vibrating head is made of wear-resistant alloy material to adapt to various road surfaces, and the end of the vibrating head is provided with a wear-resistant vibration pad.

[0011] As an alternative implementation, the controllable seismic source is equipped with a GPS synchronization module to ensure time synchronization with the multi-channel receiving array.

[0012] As an alternative implementation, the controllable seismic source is equipped with a protection module for emergency stop in case of overtemperature / overload.

[0013] As an alternative implementation, the multi-channel receiving array is arranged in a linear array, with the spacing between adjacent detectors being 0.2 to 1.5 meters.

[0014] As an alternative implementation, the multi-channel receiver array incorporates a gain-adjustable preamplifier to suppress ambient noise.

[0015] As an alternative implementation, the processing terminal is equipped with a wireless communication module for receiving the signal transmitted by the wireless transmission system configured with the multi-channel receiving array.

[0016] As an alternative implementation, each detector has a fixing component, and different fixing components are selected according to the road surface conditions. For metal roads, a magnetic base is used as the fixing component, for non-metallic roads, gypsum / quick-drying mortar is used as the fixing component, and for loose surfaces, a detachable anchor is used as the fixing component.

[0017] The working method of the above-mentioned device includes the following steps: Acquire pipeline parameter data and ancillary structure information in the detection area, verify road structure and underground structure density, mark ground obstacles, organize traffic and set up safety isolation zones, and clearly define restricted areas and work windows; Based on the geological features and target pipeline characteristics, the source sweep bandwidth, energy, and sweep time of the controllable seismic source are set, and phase coding or linear / nonlinear sweep mode is selected; the receiving array spacing is set according to the estimated burial depth and main frequency, the number and aperture of the detectors are determined, and the front-end bandpass and anti-aliasing filter parameters, sampling rate, and dynamic range are set. Deploy a controllable seismic source and a multi-channel receiving array. The multi-channel receiving array is centrally located along the detection path, with its ends appropriately extended to improve geometric illumination, ensure the coupling consistency of the detectors, and record the coupling level. A seismic source point is set on each side of the multi-channel receiving array to form a dual-point excitation mode. Controllable seismic waves are excited using a controllable seismic source, and signals are acquired by a multi-channel receiving array. The controllable seismic source excites seismic waves according to preset parameters, and the signal acquisition terminal is triggered synchronously to record data. Each seismic source point is repeatedly excited multiple times, and the average signal value is taken to suppress random noise. The monitoring reference channel-main channel cross-correlation peak value, surface wave energy ratio, direct wave arrival time drift, amplitude frequency response and coupling consistency are monitored. When the data signal-to-noise ratio or other indicators do not meet the requirements, the sweep frequency energy / duration is adjusted, the detection coupling is improved or supplementary points are added to achieve closed-loop correction. Preprocessing, adaptive filtering, reflected wave feature extraction, and three-dimensional imaging of the seismic source trigger signal and detection signal are performed to obtain the pipeline imaging results.

[0018] As an alternative implementation, the preprocessing process includes: delinearizing, detrending, anti-aliasing resampling, and bandpass and channel energy equalization of the original recording; wavelet correction and phase unification are performed using reference channel-assisted stable deconvolution / matched filtering to reduce the impact of amplitude and phase mismatch on subsequent imaging.

[0019] As an alternative implementation method, the adaptive filtering process includes: using a multi-layer decomposition wavelet basis to eliminate low-frequency environmental vibrations and high-frequency mechanical noise from the controllable source detection data, combined with adaptive noise cancellation / frequency domain Wiener filtering based on the reference channel to suppress narrowband interference; and setting a directional window in the f–k or τ–p domain to suppress surface waves and slant interference.

[0020] As an alternative implementation method, the process of extracting reflected wave features includes: separating direct waves, pipeline reflected waves, and stratum reflected waves using a wavefield separation algorithm based on cross-correlation analysis, and extracting envelope, instantaneous frequency / phase, and coherence attributes; constructing a matched filter template for cylindrical targets to perform correlation detection and output target scores, thereby enhancing the response and suppressing false detections.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention aims to solve key technical problems in existing underground pipeline detection technologies, such as uncontrollable seismic source parameters, weak anti-interference ability, difficulty in identifying non-metallic pipelines, and insufficient real-time processing capability. By innovatively integrating controllable seismic source technology, multi-channel array receiving technology, intelligent signal processing technology, and real-time imaging technology, this invention achieves high-precision and high-efficiency detection of underground pipelines of various materials, providing advanced technical means for the refined management of urban underground space.

[0022] This invention uses a controllable vibration source to adjust the frequency and energy, adapting to geological conditions, thereby improving the signal-to-noise ratio of pipeline reflected waves and solving the problem of weak signals in deep environments. This invention effectively suppresses urban environmental noise by combining multi-channel array reception with adaptive filtering, significantly reduces interference from urban power frequency, motors, traffic, etc., ensures the continuity of the same phase axis, and has strong anti-interference ability. This invention is sensitive to both metallic and non-metallic pipes; by using dwell frequency and velocity-constrained imaging, it improves the detection accuracy of small-diameter non-metallic pipes and has wide applicability. This invention can output burial depth, error and confidence interval based on tomographic velocity and reverse time migration imaging, which is convenient for engineering acceptance and comparison. Moreover, the entire detection process is a trenchless operation, which is suitable for complex scenarios such as urban main roads and residential areas.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0025] Figure 1 A schematic diagram of a city pipeline detection device based on a controllable seismic source; Figure 2 This is a schematic diagram of a controllable seismic source structure. Figure 3 This is a flowchart of the pipeline imaging signal processing. The components include: 1. Controllable seismic source, 2. Wireless detector, 3. Processing terminal, 4. Underground pipeline, 5. Parameter adjustment component, 6. GPS synchronization module, 7. Controllable drive module, 8. Hydraulic pump, and 9. Wear-resistant vibration pad. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0028] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0029] Where there is no conflict, the embodiments and features described in this application may be combined with each other.

[0030] Example 1 A controllable seismic source-based urban pipeline detection device, such as Figure 1As shown, the device integrates a controllable seismic source 1, a multi-channel receiving array, and a processing terminal 3 to achieve accurate detection and real-time imaging of underground pipes or underground pipelines 4.

[0031] The entire device adopts a modular design concept, with each module connected through standardized interfaces, which not only ensures the overall performance of the system, but also has good scalability and maintainability.

[0032] Among them, controllable seismic source 1, such as Figure 2 As shown, it consists of a hydraulic drive unit (hydraulic pump 8 in this embodiment), a vibrating head, a parameter adjustment component 5, a GPS synchronization module 6, and a controllable drive module 7, and is used to excite a sweep frequency signal at a specified location; The hydraulic drive unit can adjust the excitation energy (50~5000J in this embodiment), frequency (20~500Hz in this embodiment), and waveform (sine wave / square wave in this embodiment). The frequency sweep mode supports linear / segmented. The duration of each excitation can be adaptively selected according to the depth / material. A dwell frequency point can be set in the middle of the frequency sweep to enhance the response to a specific pipe diameter.

[0033] The parameter adjustment component 5 is connected to the controllable drive module 7. The hydraulic drive unit is controlled by the controllable drive module 7. The parameter adjustment component 5 is used to receive the user's configuration parameters and transmit them to the controllable drive module 7, thereby changing the parameters of the hydraulic drive unit.

[0034] In this embodiment, the controllable vibration source 1 is equipped with a GPS synchronization module 6 to ensure time synchronization with the receiving end; and the vibration head is set at the bottom of the hydraulic drive unit and is made of wear-resistant alloy material to adapt to various road surfaces such as asphalt, concrete, and soil; in some embodiments, the end of the vibration head is also provided with a wear-resistant vibration pad 9 to increase the vibration area and wear resistance.

[0035] The controllable seismic source 1 is also equipped with protective components, featuring over-temperature / overload protection and emergency stop functions, and an operating temperature range of [missing information]. 20~55℃; noise and vibration meet the limits for municipal operations.

[0036] The multi-channel receiving array includes multiple wireless detectors 2, each with a sensitivity ≥100mV / g. The specific number can be flexibly configured between 24 and 64 to adapt to the needs of detection tasks of different scales. The multi-channel receiving array is arranged in a linear array (in this embodiment, the spacing is 0.2~1.5 meters).

[0037] In this embodiment, the multi-channel receiving array has a built-in preamplifier (adjustable gain 0~60dB) to suppress ambient noise.

[0038] In this embodiment, the multi-channel receiving array supports the synchronous acquisition of seismic source trigger signals and array received signals, which can be wirelessly transmitted to the data processing unit. The wireless transmission system adopts the latest WiFi 6E technology standard to achieve high-speed, stable, and secure data transmission. The effective transmission distance can reach 500 meters in open environments, and a reliable communication distance of over 200 meters can be guaranteed even in complex urban environments.

[0039] In this embodiment, each wireless detector 2 in the multi-channel receiving array adopts a different coupling method according to the road surface conditions. For metal road surfaces, a magnetic base is used, and for non-metal road surfaces, gypsum / quick-drying mortar is used. Loose ground surfaces can be supplemented with detachable anchors.

[0040] The processing terminal 3 includes an intelligent data processing unit for processing seismic source trigger signals and array received signals. It has a built-in dedicated algorithm module that can perform adaptive filtering of the probe data, extraction of reflected wave features, and three-dimensional imaging to obtain pipeline imaging results. Specifically: the adaptive wavelet filtering algorithm uses a multi-layer decomposition wavelet basis to filter out low-frequency environmental vibrations and high-frequency noise; the reflected wave feature extraction uses a wavefield separation algorithm based on cross-correlation analysis to separate the direct wave, pipeline reflected wave, and stratum reflected wave to extract the pipeline reflected signal; the three-dimensional imaging uses tomographic wave velocity inversion to obtain the near-surface velocity field and employs a reverse time migration imaging method.

[0041] The intelligent data processing unit outputs the signal-to-noise ratio and cross-correlation peak value in real time; after the task is completed, it outputs indicators such as positioning error, burial depth error and confidence interval.

[0042] Example 2 A method for detecting urban pipelines based on a controllable seismic source is proposed to fully leverage the technological advantages of the device and achieve high-precision pipeline detection through a systematic detection process and scientific parameter optimization strategies.

[0043] The entire methodology has undergone extensive field verification and optimization, resulting in standardized operating procedures, which mainly include: On-site survey, collect historical data on pipelines in the detection area (pipe diameter, material, estimated burial depth, age, direction, etc.), information on ancillary structures (valve wells, inspection wells, branch points, etc.), verify road structure (asphalt / concrete thickness, base layer type, etc.) and density of underground structures, mark ground obstacles (manhole covers, cable wells, traffic barriers, tree pits, anchor bolts, etc.), complete traffic organization and safety isolation zone setting, and clarify restricted areas and work windows; Parameter configuration involves setting the source sweep bandwidth, energy, and scanning time based on the geological features and target pipeline characteristics, and appropriately selecting phase coding or linear / nonlinear sweep mode; setting the receiver array spacing based on the estimated burial depth and main frequency, determining the number and aperture of detectors, setting the front-end bandpass and anti-aliasing filter parameters, sampling rate, and dynamic range, and generating a field parameter card; The source and receiving array are deployed with the receiving array centered along the detection route and the ends extended to improve geometric illumination. The detectors are fixed to the metal road surface with magnetic bases or to the non-metallic road surface with plaster / coupling adhesive to ensure coupling consistency and record the coupling level. One source point is set on each side of the array to form a dual-point excitation mode. If necessary, an alternating excitation sequence is used to improve reciprocity constraint and signal redundancy, and a side verification line is reserved to achieve triangulation. Controllable seismic wave excitation and signal acquisition: The controllable source excites seismic waves according to preset parameters, and the signal acquisition terminal is triggered to record data synchronously. Each source point is repeatedly excited 3 to 5 times, and the average value of the signal is taken to suppress random noise.

[0044] On-site quality control involves real-time monitoring of the reference channel-main channel cross-correlation peak value, surface wave energy ratio, direct wave arrival time drift, amplitude-frequency response, and coupling consistency. When the data signal-to-noise ratio or other indicators do not meet the requirements, the sweep frequency energy / duration is adjusted, the detection coupling is improved, or additional points are added for on-site closed-loop correction. like Figure 3 As shown, the controllable source data processing and imaging methods mainly include preprocessing and wavelet correction, adaptive filtering, reflected wave feature extraction, and three-dimensional imaging.

[0045] In this embodiment, preprocessing and wavelet correction are performed on the original recording by delinearizing, detrending, anti-aliasing resampling, and bandpass and channel energy equalization; reference channel-assisted stable deconvolution / matched filtering is used to perform wavelet correction and phase unification, reducing the impact of amplitude and phase mismatch on subsequent imaging. In this embodiment, the adaptive filtering method eliminates low-frequency environmental vibration and high-frequency mechanical noise by using a multi-layer decomposition wavelet basis on the controllable source detection data, and combines adaptive noise cancellation / frequency domain Wiener filtering based on the reference channel to suppress narrowband interference; a direction window is set in the f–k or τ–p domain to suppress surface waves and oblique interference, and if necessary, prediction wavelets are used to destroy and preserve reflection details. In this embodiment, a wavefield separation algorithm based on cross-correlation analysis separates direct waves, pipeline reflected waves, and formation reflected waves, and extracts attributes such as envelope, instantaneous frequency / phase, and coherence (semblance / phase consistency); a matched filter template for cylindrical targets is constructed for correlation detection and target score is output, thereby enhancing the response of weak "diffraction samples" and suppressing false detections; In this embodiment, the three-dimensional imaging method obtains the near-surface velocity field through tomographic wave velocity inversion and uses the reverse time migration imaging method for imaging; after the above adaptive filtering, reflected wave feature extraction and three-dimensional imaging, the pipeline imaging result is obtained, and the positioning error, burial depth error, confidence interval and other indicators are output.

[0046] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of one or more computer-usable storage media (including, but not limited to, disk storage, etc.) containing computer-usable program code. CD - ROM It takes the form of a computer program product implemented on (such as optical memory, etc.).

[0047] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0048] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0049] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A city pipeline detection device based on a controllable seismic source, characterized in that, It includes a controllable seismic source, a multi-channel receiving array, and a processing terminal, among which: The controllable vibration source includes a hydraulic pump, the bottom of which is connected to a vibrating head. The hydraulic pump is controlled by a controllable drive module to change the energy, frequency, and / or waveform excited by the vibrating head. The multi-channel receiving array includes multiple detectors spaced apart, the arrangement of which is determined according to the requirements of the detection mission, and is used to acquire the source trigger signal and the detection signal; The processing terminal is used to perform adaptive filtering, reflected wave feature extraction, and three-dimensional imaging on the seismic source trigger signal and detection signal to obtain pipeline imaging results.

2. The urban pipeline detection device based on a controllable seismic source as described in claim 1, characterized in that, The vibrating head is made of wear-resistant alloy material to adapt to various road surfaces, and the end of the vibrating head is equipped with a wear-resistant vibration pad.

3. The urban pipeline detection device based on a controllable seismic source as described in claim 1, characterized in that, The controllable seismic source is equipped with a GPS synchronization module to ensure time synchronization with the multi-channel receiving array; Alternatively, the controllable seismic source may be equipped with a protection module for emergency stop in case of over-temperature / overload.

4. The urban pipeline detection device based on a controllable seismic source as described in claim 1, characterized in that, The multi-channel receiving array is arranged in a linear array, with the spacing between adjacent detectors being 0.2 to 1.5 meters; Alternatively, the multi-channel receiver array may incorporate a gain-adjustable preamplifier to suppress ambient noise.

5. The urban pipeline detection device based on a controllable seismic source as described in claim 1, characterized in that, The processing terminal is equipped with a wireless communication module for receiving the signal transmitted by the wireless transmission system configured with the multi-channel receiving array.

6. The urban pipeline detection device based on a controllable seismic source as described in claim 1, characterized in that, Each detector has a fixing component, and different fixing components are selected according to the road surface conditions. Magnetic bases are used as fixing components for metal roads, gypsum / quick-drying mortar are used as fixing components for non-metallic roads, and detachable anchors are used as fixing components for loose ground surfaces.

7. A method of operating the apparatus based on any one of claims 1-6, characterized in that, Includes the following steps: Acquire pipeline parameter data and ancillary structure information in the detection area, verify road structure and underground structure density, mark ground obstacles, organize traffic and set up safety isolation zones, and clearly define restricted areas and work windows; Based on the geological features and the characteristics of the target pipeline, the source sweep bandwidth, energy, and sweep time of the controllable seismic source are set, and phase coding or linear / nonlinear sweep mode is selected; the receiving array spacing is set according to the estimated burial depth and the main frequency, the number and aperture of the detectors are determined, and the front-end bandpass and anti-aliasing filter parameters, sampling rate, and dynamic range are set. Deploy a controllable seismic source and a multi-channel receiving array. The multi-channel receiving array is centrally located along the detection path, with its ends appropriately extended to improve geometric illumination, ensure the coupling consistency of the detectors, and record the coupling level. Set a seismic source point on each side of the multi-channel receiving array to form a dual-point excitation mode. Controllable seismic waves are excited using a controllable seismic source, and signals are acquired by a multi-channel receiving array. The controllable seismic source excites seismic waves according to preset parameters, and the signal acquisition terminal is triggered synchronously to record data. Each seismic source point is repeatedly excited multiple times, and the average signal value is taken to suppress random noise. The monitoring reference channel-main channel cross-correlation peak value, surface wave energy ratio, direct wave arrival time drift, amplitude frequency response and coupling consistency are monitored. When the data signal-to-noise ratio or other indicators do not meet the requirements, the sweep frequency energy / duration is adjusted, the detection coupling is improved or supplementary points are added to achieve closed-loop correction. Preprocessing, adaptive filtering, reflected wave feature extraction, and three-dimensional imaging of the seismic source trigger signal and detection signal are performed to obtain the pipeline imaging results.

8. The method of claim 7, characterized in that, The preprocessing process includes: delinearizing, detrending, anti-aliasing resampling, and bandpass and channel energy equalization of the original recording; wavelet correction and phase unification are performed using reference channel-assisted stable deconvolution / matched filtering to reduce the impact of amplitude and phase mismatch on subsequent imaging.

9. The method of claim 7, characterized in that, The adaptive filtering process includes: using multi-layer decomposition wavelet basis to eliminate low-frequency environmental vibration and high-frequency mechanical noise from controllable source detection data, combined with adaptive noise cancellation / frequency domain Wiener filtering based on reference channel to suppress narrowband interference; and setting directional windows in the f–k or τ–p domain to suppress surface waves and slant interference.

10. The method of claim 7, characterized in that, The process of extracting reflected wave features includes: separating direct waves, pipeline reflected waves, and stratum reflected waves using a wavefield separation algorithm based on cross-correlation analysis, and extracting envelope, instantaneous frequency / phase, and coherence attributes; constructing a matched filter template for cylindrical targets to perform correlation detection and output target scores, thereby enhancing the response and suppressing false detections.

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