Underwater stratum structure three-dimensional detecting device and method using phased ultrasonic surface array three-dimensional focusing

Abstract

The application discloses a kind of underwater stratum structure three-dimensional detection devices of phased ultrasonic surface array three-dimensional focusing, it is installed with ultrasonic wave transmitting transducer group and ultrasonic wave receiving transducer on the circular ultrasonic transducer surface array, and phased control ultrasonic wave emission drive module is used to be controlled under the control of control processing module, utilizes the principle of surface array phase control to operate ultrasonic wave transmitting transducer group on circular ultrasonic transducer surface array, realizes the phased focusing and phased scanning ultrasonic wave emission of phased control, ultrasonic wave receiving transducer is used to receive the ultrasonic wave signal reflected back by phased focusing and phased scanning ultrasonic wave emission, control processing module is used to carry out imaging processing to the ultrasonic wave signal reflected back by phased focusing and phased scanning emission ultrasonic wave, obtains three-dimensional amplitude image.The application has the characteristics of good focusing effect, large energy, high resolution and deep detection.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering exploration technology, specifically to a three-dimensional underwater geological structure detection device and method using phased-array ultrasonic three-dimensional focusing. Background Technology

[0002] With the continuous development of society, economy, and technology, engineering construction has gradually expanded from land to water, ocean, and underwater engineering, which involves underwater exploration technology. In recent years, underwater exploration technology has developed rapidly. Within this field, acoustic detection technology has been widely applied. It can be used to detect large marine facilities, rocks, and seabed sediments, and also to solve communication problems for divers in the deep sea. Currently, the vast majority of underwater acoustic detection technology mainframes are used for underwater topography and underwater structure measurement, while technologies for acoustic phased arrays for underwater geological structure detection are rare. Furthermore, underwater engineering fine-scale surveying technologies and miniaturized equipment used in engineering construction are relatively far behind those used on land.

[0003] The recently developed sonar detection technology for karst caves at the pile bottom is one of the earliest researched and invented underwater acoustic detection technologies and equipment in the field of land-based underwater exploration. It (Patent 1: A sonar detection device and method for karst caves at the pile bottom, CN 104101896A) uses a transducer placed at the pile bottom to excite and receive ultrasonic waves via mud coupling to detect the development of karst at the pile bottom. However, the device has limited data acquisition and a fixed offset distance, making it unable to collect high-density reflected wave data from multiple angles and offset distances. Its identification of karst at the pile bottom mainly relies on recognizing changes in reflected waveforms and analyzing the waveform's time-frequency characteristics, which cannot determine the extent of the karst cave. Furthermore, the detection is easily affected by interference from surface wave reflections from the borehole wall. Completely solving the problem of karst detection at the pile bottom remains challenging.

[0004] A search of existing technologies revealed:

[0005] Patent 2, "Method, Device and System, Electronic Equipment and Storage Medium for Detecting Karst at the Bottom of Pile (CN112630764A)," uses a transducer array with transmit delay control to perform beam phase control on each sensor for three-dimensional detection of the pile bottom. It uses each group of transducers in a certain direction to perform linear phase detection in that direction, and then switches to another vertical direction for detection with the same control. It is a square transducer array, and it is a linear phase control detection, which only performs phase scanning in two directions and cannot cover the entire pile bottom detection range.

[0006] Patent 3, "A Three-Dimensional Detection Method, Device, Equipment, and Storage Medium (CN112817039A)," describes a detection system comprising multiple sensors arranged in a two-dimensional array. Each sensor can emit and receive acoustic signals. A first sensor corresponding to a preset unit in the detection system emits an acoustic signal, and a second sensor receives the reflected signal covering the bottom of the pile. The preset unit includes point units, line units, and surface units, corresponding to point areas, line areas, and surface areas in the two-dimensional array. It utilizes one transducer, a row (line, group), or a surface (several transducers forming a small surface) in the two-dimensional array for emission, and then uses another transducer, a row (line, group), or a surface (several transducers forming a small surface) for reception. It can be a single transducer emitting and a single transducer receiving, or a line of transducers emitting and a line of transducers receiving, or a small portion of a surface transducer emitting and another small portion of a surface transducer receiving; it is a true phased-array focused emission. However, the emission energy is low, and the detection depth is limited.

[0007] Patent 4, "A Three-Dimensional Detection Method, Device, Equipment, and Storage Medium (CN112904348A)," uses multiple transducers arranged in a one-dimensional linear array to perform three-dimensional detection of the pile bottom through a single-transmitter-multiple-receiver acquisition method combined with rotational acquisition. It is not a linear phase-array detection technology; instead, it uses a single transducer to transmit, while multiple other transducers in a group receive, employing multi-channel signal superposition processing to complete the detection and analysis in a specific direction. It uses only one line of transducers, with one transmitting and the others receiving independently, then superimposing the signals. It is neither phased-array nor linear-array transmission, resulting in low transmission energy, limited detection depth, and poor resolution. It uses a motor to mechanically rotate the transducer 180 degrees to complete the scanning detection.

[0008] Patent 5, "A Three-Dimensional High-Precision Scanning Detection System and Method for Karst at the Bottom of a Pile (CN 115639590A)," utilizes linear phased array scanning to acquire data. It drives the array transducers to rotate according to a fixed rotation angle, repeating the phased array scanning process after each fixed rotation angle. Its structure and transducer sensors are identical to those of Patent 4. The difference lies in that Patent 5 uses a group of transducers for linear phased array scanning to complete a single detection in a specific direction, while Patent 4 employs a single transducer for transmission, with multiple other transducers in the group receiving signals, using multi-channel signal superposition processing technology to complete the detection and analysis in a specific direction. This is a linear phased array transmission, with a motor mechanically driving the transducers to rotate 180 degrees to complete the detection. It is not a planar phased array transmission.

[0009] Since the aforementioned patented technologies employ signal superposition, linear phase control, or local phase control techniques, they lack focusing functionality or have only local focusing capabilities, resulting in unsatisfactory focusing effects that cannot meet the needs of detecting complex deep underwater strata. Summary of the Invention

[0010] The purpose of this invention is to provide a three-dimensional underwater geological structure detection device and method with phased-array ultrasonic three-dimensional focusing. This invention has the characteristics of good focusing effect, high energy, high resolution and deep detection.

[0011] To achieve this objective, the present invention provides a phased-array ultrasonic array three-dimensional focusing underwater stratum structure three-dimensional detection device, which includes a circular ultrasonic transducer array, a phased-array ultrasonic transmission drive module, and a control and processing module.

[0012] The circular ultrasonic transducer array is equipped with an ultrasonic transmitting transducer group and an ultrasonic receiving transducer. The phased-array ultrasonic transmission drive module is used to manipulate the ultrasonic transmitting transducer group on the circular ultrasonic transducer array to achieve phased-array focusing and phased-array scanning ultrasonic transmission under the control of the control processing module. The ultrasonic receiving transducer is used to receive the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning ultrasonic transmission. The control processing module is used to perform imaging processing on the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning ultrasonic transmission to obtain a three-dimensional amplitude image.

[0013] The beneficial effects of this invention are:

[0014] This invention utilizes a circular ultrasonic transducer array employing phased-array focusing and phased-array scanning to emit ultrasonic waves. First, it employs a phased-array array for emission, with all transducers focusing the emission, resulting in excellent focusing effect, high energy, and deep detection. Second, it uses electronic phased-array scanning for detection, providing multiple emission and acquisition points, good directivity, and the ability to zoom and scan for different detection depths, resulting in high resolution. It can acquire multi-angle, high-density reflected wave data, which is beneficial for determining the extent of caverns. Furthermore, the detection is not affected by surface wave reflections from the borehole walls, enabling the detection of geological structures at greater depths. Attached Figure Description

[0015] Figure 1 A schematic diagram of an underwater three-dimensional geological structure detection device using phased-array ultrasonic three-dimensional focusing;

[0016] Figure 2 A schematic diagram of the electrical control cabinet in an underwater three-dimensional geological structure detection device using phased-array ultrasonic three-dimensional focusing.

[0017] Figure 3 A schematic diagram of an underwater three-dimensional geological structure detection device using a mechanically controlled phased ultrasonic array three-dimensional focusing system.

[0018] Figure 4 A schematic diagram of the electrical control cabinet in an underwater three-dimensional geological structure detection device with mechanically controlled phased ultrasonic array three-dimensional focusing.

[0019] Figure 5This is a schematic diagram of the circular ultrasonic transducer array in this invention;

[0020] Figure 6 This is a schematic diagram of phased-array focusing and phased-array scanning in this invention;

[0021] Among them, 1—circular ultrasonic transducer array, 2—ultrasonic transmitting transducer group, 3—ultrasonic receiving transducer, 4—circuit control cavity, 5—phase-controlled ultrasonic transmitting drive module, 6—control processing module, 7—attitude sensor module, 8—mechanical universal controller, and 9—water passage hole. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0023] Example 1:

[0024] like Figure 1 and 2 The underwater three-dimensional geological structure detection device shown is a phased-array ultrasonic array three-dimensional focusing device, which includes a circular ultrasonic transducer array 1, a phased-array ultrasonic transmission drive module 5, and a control and processing module 6.

[0025] The circular ultrasonic transducer array 1 is equipped with an ultrasonic transmitting transducer group 2 and an ultrasonic receiving transducer 3. The phased control ultrasonic transmission drive module 5 is used to manipulate the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased focusing and phased scanning ultrasonic transmission under the control of the control processing module 6. (Focusing is the detection of a point, which can be focused into different focal lengths, playing the role of detection depth, which is the vertical axis; scanning is scanning to different angles (positions), which is the horizontal axis.) The ultrasonic receiving transducer 3 is used to receive the ultrasonic signals reflected back from the phased focusing and phased scanning ultrasonic transmission. The control processing module 6 is used to perform imaging processing on the ultrasonic signals reflected back from the phased focusing and phased scanning ultrasonic transmission to obtain a three-dimensional amplitude image.

[0026] In the above technical solution, an ultrasonic receiving transducer 3 is disposed at the center of the circular ultrasonic transducer array 1. Around the ultrasonic receiving transducer 3, 1 to 10 rings of ultrasonic transmitting transducer groups 2 are arranged, each ring containing multiple circumferentially arranged ultrasonic transmitting transducers. The more rings of ultrasonic receiving transducers 3 arranged, the better the focusing effect of the emitted ultrasonic waves. However, considering the size of the circular ultrasonic transducer array 1 and the convenience of detection, the number of rings of the ultrasonic transmitting transducer groups 2 is set to 1 to 10. Figure 5 As shown.

[0027] In the above technical solution, the circular ultrasonic transducer array 1 adopts a circular arrangement. The circular arrangement of the transmitting transducer has a good emission focusing effect, and the focused waveform is uniform and symmetrical. It also benefits the consistency of the received signals from all scanning and detection, which is conducive to the analysis and interpretation of the detected strata. The circular ultrasonic transducer array 1 is provided with a water passage hole 9. The water passage hole 9 is used to ensure that the circular ultrasonic transducer array 1 can be lowered freely in water without drifting (slipping).

[0028] In the above technical solution, the area around the center of the circular ultrasonic transducer array 1 consists entirely of ultrasonic transmitting transducers. It does not need to function as an ultrasonic receiving transducer, allowing for the use of high-power transmitting transducers and increasing the detection depth. Ultrasonic transmitting materials are generally classified as transmitting, receiving, or transmitting-receiving. For transducers of the same size, when used solely as a transmitting transducer, using a high-power transmitting material will result in a higher transmitting power. When used solely as a receiving transducer, using a highly sensitive material for the same size will result in a higher receiving sensitivity. When used for both transmitting and receiving, to balance the characteristics of both, the transmitting power of the same material will be lower, and the receiving sensitivity will also be lower.

[0029] The ultrasonic receiving transducer 3 of the circular ultrasonic transducer array 1 is only used to receive reflected ultrasonic signals. It does not need to be a transducer that can be used for both transmitting and receiving. A highly sensitive receiving transducer can be used to improve the reception capability of weak signals. At the same time, it reduces the inconsistency of signals caused by the difference in the receiving performance of different transducers and improves the quality of detection signal analysis.

[0030] The above technical solution also includes a circuit control cavity 4 and a three-dimensional attitude module 7. The phased-controlled ultrasonic wave transmission drive module 5, the control processing module 6, and the three-dimensional attitude module 7 are installed in the circuit control cavity 4. The attitude sensor module 7 is used to monitor the horizontal attitude and the orientation of the circular ultrasonic transducer array 1 in order to determine the orientation of the detected geological structure. The attitude sensor module 7 transmits the horizontal attitude and the orientation of the circular ultrasonic transducer array 1 to the control processing module 6. The control processing module 6 performs imaging processing on the ultrasonic wave signals reflected back from the phased-controlled focusing and phased-controlled scanning emitted ultrasonic waves, and obtains a three-dimensional amplitude image by combining the horizontal attitude and the orientation of the circular ultrasonic transducer array 1.

[0031] In the above technical solution, the phased-array ultrasonic emission drive module 5, under the control of the control processing module 6, uses the principle of array phase control to manipulate the ultrasonic emission transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased-array focusing and phased-array scanning ultrasonic emission. The process is as follows:

[0032] Under the control of the control and processing module 6, the phased-array ultrasonic transmission drive module 5 controls the ultrasonic focusing cylinder of the circular ultrasonic transducer array 1 to scan and detect at any angle from 0 to 45 degrees perpendicular to the plane of the ground, ultimately forming a fan-shaped three-dimensional detection range with an angle of 0 to 90 degrees. This enables fine detection at different focal lengths, achieving refined depth detection with high resolution. It also enables fine deflection (scanning) detection of the focused acoustic column. The circular array has good focusing characteristics, symmetrical waveforms, and good signal consistency.

[0033] The specific method for achieving phased-array focusing and phased-array scanning ultrasonic wave emission in the above technical solution is as follows:

[0034] For any ultrasonic transducer B in the nth ring of ultrasonic transducers in ultrasonic transducer group 2, in geometric triangle OPB: OB=n·d.

[0035] Wherein, point O is the center point of the circular ultrasonic transducer array 1, and the ultrasonic receiving transducer 3 is arranged at the center point; point B is the center position of the ultrasonic transmitting transducer B; and point P is the focusing focal length of the ultrasonic transmitting transducer group 2.

[0036] According to Yu Xuan's theorem and trigonometric transformations, we have: PB 2 =(nd) 2 +F 2 +2Fndsinθ

[0037] Wherein: PB is the distance from the ultrasonic transducer B to the focusing focal length of the ultrasonic transducer group 2; F is the distance from the center point of the circular ultrasonic transducer array 1 to the focusing focal length of the ultrasonic transducer group 2; θ is the angle between the sound beam and the normal after deflection; and d is the distance between the centers of two adjacent ultrasonic transducers on the same diameter.

[0038] The acoustic path difference between the ultrasonic transducer B and the center point of the circular ultrasonic transducer array 1 is: ΔS = F - PB.

[0039] The delay value Δtn of the ultrasonic transmitting transducer B relative to the ultrasonic receiving transducer 3 at the center point of the circular ultrasonic transducer array 1 is: Δtn = ΔS / v. As long as the sound wave is not focused on the vertical center, focusing on other points achieves focusing and phase control, such as... Figure 6 As shown.

[0040] In the above technical solution, the specific method by which the control processing module 6 performs imaging processing on the ultrasonic signals reflected back from phased-array focusing and phased-array scanning ultrasonic waves to obtain a three-dimensional amplitude image is as follows:

[0041] The ultrasonic signals emitted and reflected by phased-focused and phased-scan ultrasonic waves are converted into time depth according to time to obtain the coordinates corresponding to the amplitude values ​​at different positions at different times. After three-dimensional interpolation, a three-dimensional amplitude image is obtained, which realizes the fine imaging of the detection data.

[0042] In the above technical solution, the coordinates corresponding to the amplitude values ​​at different positions at different times are calculated as follows:

[0043] x=V*t*sinφ, y=V*t*cosφ, z=V*t*sinθ

[0044] Where x, y, and z represent the x-coordinate, y-coordinate, and vertical coordinate of a point in the three-dimensional detection imaging, V is the propagation speed of ultrasound in the geological medium, φ is the angle (fixed rotation angle) between a baseline passing through the center point of the circular ultrasonic transducer array 1 directly above the focal point and the lines connecting other ultrasonic transducers passing through the center of the circle, and θ is the phase angle (phase angle) between the focal point and the lines connecting the ultrasonic transducers passing through the center of the circle.

[0045] A three-dimensional detection method using the above-mentioned device includes the following steps;

[0046] Step 1: Under the control of the control and processing module 6, the phased control ultrasonic emission drive module 5 uses the principle of phase control of the array to manipulate the ultrasonic emission transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased focusing and phased scanning ultrasonic emission.

[0047] Step 2: The ultrasonic receiving transducer 3 receives the ultrasonic signals reflected back from the phased-focus and phased-scan ultrasonic waves emitted by the phased-focus and phased-scan ultrasonic waves.

[0048] Step 3: The control processing module 6 performs imaging processing on the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning emitted ultrasonic waves to obtain a three-dimensional amplitude image.

[0049] The detection method of the present invention involves deploying a circular ultrasonic transducer array 1 to the bottom of the water and using a control processing module 6 to perform focused scanning of all ultrasonic emission sensors for fine three-dimensional detection of the geological structure. First, the ultrasonic emission transducer group 2 in the circular ultrasonic transducer array 1 generates a focused ultrasonic cylindrical field through the control processing module 6. Then, the focused ultrasonic cylindrical field is controlled to vertically probe the geological plane with an arbitrary angle of 0 to 45 degrees, ultimately forming a fan-shaped three-dimensional detection range with an angle of 0 to 90 degrees.

[0050] When dragging and scanning, two-dimensional scanning is performed at an angle of 0 to 45 degrees to the left and right (positive and negative) of the vertical dragging direction, forming a fan-shaped detection profile with an angle of 0 to 90 degrees. Then, the two-dimensional scanning is repeated at an angle of 0 to 45 degrees to the left and right after dragging each detection point, finally forming a three-dimensional detection range of a fan-shaped stratigraphic structure with an angle of 0 to 90 degrees.

[0051] When using a static single-point detection method, the vertical plane of the strata is used as the first detection point. Then, a 360-degree rotational scan is performed with the focusing angle of 0 to 5 degrees between the vertical plane of the strata as the step angle. The detection is completed when the angle between the vertical plane of the strata is 0 to 45 degrees, forming a cone-shaped three-dimensional detection body with a single-point angle of 0 to 90 degrees.

[0052] The main functions of an ultrasonic phased array are: sector scanning and dynamic depth scanning.

[0053] S-scan, also known as sector scanning, involves calculating the focusing delay for each deflection angle at a set depth using a phased array probe according to focusing rules. During excitation, these deflections are performed sequentially from left to right, forming a sector scan within a defined range. The scanning range, angle interval, and focusing depth must be set during the scan.

[0054] The dynamic depth scanning method used in this invention, also known as dynamic depth focusing (phased focusing and phased scanning), involves scanning the ultrasonic beam along the transducer's central axis at focal points of different depths. Dynamic depth focusing imaging provides better results than conventional sector scanning imaging. As its principle suggests, the most significant characteristic of ultrasonic phased arrays is their ability to flexibly, conveniently, and effectively control the beam shape, greatly improving detection efficiency.

[0055] Example 2:

[0056] A mechanically controlled phased-array ultrasonic three-dimensional focusing underwater stratum structure three-dimensional detection device, such as... Figure 3 and 4 As shown: It includes a circular ultrasonic transducer array 1, a circuit control cavity 4, a phased control ultrasonic emission drive module 5, a control processing module 6, and a mechanical universal controller 8.

[0057] The circular ultrasonic transducer array 1 is equipped with an ultrasonic transmitting transducer group 2 and an ultrasonic receiving transducer 3. The phased-array ultrasonic transmitting drive module 5 and the control processing module 6 are installed in the circuit control cavity 4. The phased-array ultrasonic transmitting drive module 5 is used to manipulate the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased-array focusing under the control of the control processing module 6 using the principle of array phase control. The mechanical universal controller 8 is used to manipulate the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased-array scanning under the control of the control processing module 6. During the phased-array focusing and phased-array scanning process, the control processing module 6 controls the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 to achieve ultrasonic transmission. The ultrasonic receiving transducer 3 is used to receive the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning ultrasonic transmission. The control processing module 6 is used to perform imaging processing on the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning ultrasonic transmission to obtain a three-dimensional amplitude image.

[0058] In the above technical solution, the phased control ultrasonic emission drive module 5, under the control of the control processing module 6, uses the principle of phase control of the array to manipulate the ultrasonic emission transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased focused ultrasonic emission. The specific method is as follows: an ultrasonic emission transducer group 2 passing through the diameter of the circular ultrasonic transducer array 1, with the center as the midpoint, the delayed emission between the ultrasonic emission transducers can play the role of adjusting the focusing focal length.

[0059] The specific method by which the mechanical universal controller 8 manipulates the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 to achieve phased scanning under the control of the control processing module 6 is as follows: Under the control of the mechanical universal controller 8, the ultrasonic transmitting transducer group 2 on the circular ultrasonic transducer array 1 is manipulated to complete the scanning detection of any angle direction of 0 to 45 degrees in the vertical detection stratum plane, and finally form a fan-shaped three-dimensional detection range with an angle of 0 to 90 degrees.

[0060] The above technical solution also includes a three-dimensional attitude module 7, which is installed in the circuit control cavity 4. The attitude sensor module 7 is used to monitor the horizontal attitude and orientation of the circular ultrasonic transducer array 1 in order to determine the orientation of the detected geological structure. The attitude sensor module 7 transmits the horizontal attitude and orientation of the circular ultrasonic transducer array 1 to the control processing module 6. The control processing module 6 performs imaging processing on the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning emitted ultrasonic waves, and obtains a three-dimensional amplitude image by combining the horizontal attitude and orientation of the circular ultrasonic transducer array 1.

[0061] The difference between Embodiments 1 and 2 is that when the ultrasonic transducer is electronically controlled to focus emission and scan detection, a mechanical universal controller and a mechanical universal driver are not required; when the ultrasonic transducer is only electronically controlled to focus emission, and the scanning detection is controlled by the mechanical universal controller, then the mechanical universal controller 8 is required to complete the scanning detection.

[0062] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A phased-array ultrasonic three-dimensional focusing underwater stratigraphic structure three-dimensional detection device, characterized in that, It includes a circular ultrasonic transducer array, a phased-controlled ultrasonic emission drive module, and a control processing module. An ultrasonic receiving transducer is set at the center of the circular ultrasonic transducer array. Around the ultrasonic receiving transducer, n rings of ultrasonic transmitting transducer groups are arranged. Each ring of ultrasonic transmitting transducer groups includes multiple ultrasonic transmitting transducers arranged circumferentially. The phased control ultrasonic transmission drive module is used to manipulate the ultrasonic transmitting transducer groups on the circular ultrasonic transducer array to achieve phased focusing and phased scanning ultrasonic transmission under the control of the control processing module. The ultrasonic receiving transducer is used to receive the ultrasonic signals reflected back from the phased focusing and phased scanning ultrasonic transmission. The control processing module is used to perform imaging processing on the ultrasonic signals reflected back from the phased focusing and phased scanning ultrasonic transmission to obtain a three-dimensional amplitude image. It also includes a circuit control cavity and a three-dimensional attitude module. The phased control ultrasonic wave transmission drive module, the control processing module, and the three-dimensional attitude module are installed in the circuit control cavity. The three-dimensional attitude module is used to monitor the horizontal attitude and the orientation of the circular ultrasonic transducer array and transmit them to the control processing module. The control processing module performs imaging processing on the ultrasonic wave signals reflected back from the phased focusing and phased scanning emitted ultrasonic waves, and obtains a three-dimensional amplitude image by combining the horizontal attitude and the orientation of the circular ultrasonic transducer array. The specific methods for achieving phased-array focusing and phased-array scanning ultrasonic wave emission are as follows: For any ultrasonic transducer B in the nth ring of the ultrasonic transducer group, within the geometric triangle OPB, OB = n. d; Wherein, point O is the center point of the circular ultrasonic transducer array, where the ultrasonic receiving transducer is arranged, point B is the location of the ultrasonic transmitting transducer B, and point P is the focusing focal length of the ultrasonic transmitting transducer group. According to Yu Xuan's theorem, trigonometric transformations yield: Where: PB is the distance from ultrasonic transducer B to the focal length of the ultrasonic transducer group; F is the distance from the center point of the circular ultrasonic transducer array to the focal length of the ultrasonic transducer group; θ is the angle between the deflected sound beam and the normal; and d is the distance between the centers of two adjacent ultrasonic transducers on the same diameter. The acoustic path difference between ultrasonic transducer B and the center point of the circular ultrasonic transducer array is: ΔS=F-PB. The delay value Δtn of the ultrasonic transmitting transducer B relative to the ultrasonic receiving transducer at the center point of the circular ultrasonic transducer array is: Δtn=ΔS / V, where V is the propagation speed of ultrasonic waves in the geological medium.

2. The underwater three-dimensional geological structure detection device with phased-array ultrasonic three-dimensional focusing according to claim 1, characterized in that: The phased-array ultrasonic emission drive module, under the control of the control processing module, utilizes the principle of phase control to manipulate the ultrasonic emission transducer group on the circular ultrasonic transducer array to achieve phased-array focusing and phased-array scanning ultrasonic emission. The process is as follows: Under the control of the control and processing module, the phased control ultrasonic emission drive module controls the ultrasonic focusing cylinder of the circular ultrasonic transducer array to scan and detect at any angle of 0 to 45 degrees perpendicular to the plane of the ground, ultimately forming a fan-shaped three-dimensional detection range with an angle of 0 to 90 degrees.

3. The underwater three-dimensional geological structure detection device with phased-array ultrasonic three-dimensional focusing according to claim 1, characterized in that: The control processing module performs imaging processing on the ultrasonic signals reflected back from phased-array focusing and phased-array scanning ultrasonic waves to obtain a three-dimensional amplitude image. The specific method is as follows: The ultrasonic signals emitted and reflected by phased-focused and phased-scan ultrasonic waves are converted into time depth according to time to obtain the coordinates corresponding to the amplitude values ​​at different positions at each time. After three-dimensional interpolation, a three-dimensional amplitude image is obtained.

4. The underwater three-dimensional geological structure detection device with phased-array ultrasonic three-dimensional focusing according to claim 3, characterized in that: The coordinates corresponding to the amplitude values ​​at different locations at different times are calculated as follows: x=V t sinφ,y=V t cosφ,z=V t sinθ Where x, y, and z represent the x-coordinate, y-coordinate, and vertical coordinate of a point in the three-dimensional detection imaging, V is the propagation speed of ultrasound in the geological medium, φ is the angle between a baseline passing through the center point of the circular ultrasonic transducer array directly above the focal point and the lines connecting other ultrasonic transducers passing through the center of the circle, and θ is the phase control angle between the focal point and the lines connecting the ultrasonic transducers passing through the center of the circle.

5. A three-dimensional detection method using the device of claim 1, characterized in that, It includes the following steps; Step 1: Under the control of the control processing module, the phased control ultrasonic emission drive module uses the principle of phase control of the array to manipulate the ultrasonic emission transducer group on the array of circular ultrasonic transducers to achieve phased focusing and phased scanning ultrasonic emission. Step 2: The ultrasonic receiving transducer receives the ultrasonic signals reflected back from the phased-focused and phased-scan ultrasonic waves emitted by the phased-focused and phased-scan ultrasonic waves. Step 3: The control processing module performs imaging processing on the ultrasonic signals reflected back from the phased-array focusing and phased-array scanning emitted ultrasonic waves to obtain a three-dimensional amplitude image.

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