Underwater hull positioning method and positioning system based on time delay and array topology

Abstract

The invention belongs to the technical field of underwater target detection, and particularly relates to an underwater ship body positioning method and system based on time delay and array topology, and the method comprises the steps: S1, obtaining the image data of an underwater target ship body, transmitting sound waves for detection, and receiving echoes; s2, analyzing and processing a sound wave signal received by the sound wave receiving device based on a time delay algorithm in a time difference positioning algorithm; s3, establishing an underwater three-dimensional space model, and determining position information of an underwater target ship body according to the array topological structure; and S4, according to the position information of the underwater target ship body, carrying out clustering analysis to identify the type of the ship body. The underwater ship body is detected through sound waves, the accurate position information of the underwater target ship body is determined by using a time delay algorithm in a time difference positioning algorithm and an array topological structure, clustering analysis is performed by using a K-Means algorithm, the ship body type is quickly positioned and accurately identified, and a guarantee is provided for subsequent underwater maintenance work.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater target detection, and in particular relates to an underwater ship hull positioning method and a positioning system based on time delay and array topology. Background Art

[0002] During the maintenance and repair of ships, the position positioning and identification of the underwater part of the hull is crucial. For large ships, the underwater part has a complex structure, including the bottom of the ship, propellers and other parts. Accurate positioning helps improve maintenance efficiency and reduce maintenance costs.

[0003] There are many defects in the current traditional underwater positioning methods. The positioning method based on a single sensor cannot use the multi-angle information of the signal to accurately determine the position of the hull; the multi-sensor method does not fully consider the accuracy of the delay and the optimization of the array topology in complex underwater environments, resulting in large positioning and identification errors. For example, in shallow and deep sea environments, due to the difference in sound speed profiles, sound speed correction and array topology adaptive adjustment are not performed for different environments, resulting in a significant decrease in positioning accuracy. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides an underwater hull positioning method based on time delay and array topology. The underwater target hull is detected by sound waves, and the position information of the underwater target hull is determined by using the time delay algorithm and array topology structure in the time difference positioning algorithm; finally, the hull type is identified by using the K-Means algorithm for cluster analysis, the underwater target position data is acquired, the positioning is fast, the workload is reduced, and data guarantee is provided for subsequent underwater maintenance operations.

[0005] To achieve the above object, the present invention discloses an underwater hull positioning method based on time delay and array topology, which comprises:

[0006] S1: Acquire image data of underwater target hull, transmit sound waves for detection, and receive echoes;

[0007] The image data of the underwater target ship hull is obtained by shooting with a camera, the underwater target ship hull is detected by an acoustic wave transmitting device to obtain the depth information of the hull, and the acoustic wave receiving device is used to receive the acoustic wave signal reflected back from the surface of the underwater target ship hull;

[0008] S2: Analyze and process the sound wave signal received by the sound wave receiving device based on the time delay algorithm in the time difference positioning algorithm;

[0009] The sound wave receiving device is used to determine the distance difference Δd from the sound source signal to the microphone array element. The first microphone array element in the sound wave receiving device is set as the reference point, and the sound wave signal received by the nth microphone array element at time k is obtained as follows:

[0010] y n (k) = α n s(kt-τ n1 )+v n (k)

[0011] =α n f n (τ)]+v n (k)

[0012] =x n (k)+v n (k)

[0013] Among them, y n (k) is the signal finally received by the nth array element at time k; α n (n=1,2,...,N) is the attenuation of the signal during propagation; s is the sound source signal; k is the time parameter; t is the propagation time from the sound source to the first array element; τ n1 is the signal delay difference received by the first microphone array element and the second microphone array element; v n (k) is the additive noise received on the nth array element; F n (τ) is the signal delay function between the nth array element and the first array element; x n (k) is the amount of change of the nth array element over time k;

[0014] S3: Establish an underwater three-dimensional space model and determine the position information of the underwater target hull according to the array topology structure;

[0015] Determine the direction angle and distance of the sound wave signal according to the geometric relationship between the sound source signal and the array obtained in step S2, set the axial direction of the array as the reference direction, calculate the angle formed by the sound source signal, the line connecting the center of the array and the axial direction of the array, and use it as the direction angle of the sound wave signal;

[0016] S4: According to the position information of the underwater target hull identified in step S3, the water area where the underwater target hull is located is scanned by a laser radar to obtain water area point cloud data. After noise elimination and coordinate conversion, the K-Means algorithm is used to perform cluster analysis on the water area point cloud data to identify the hull type, and the obtained underwater target hull data is sent to the detection center subsystem.

[0017] Preferably, the distance L of the underwater target hull is obtained by using the distance formula between two points in space:

[0018]

[0019] Among them, L is the distance of the underwater target hull; x0 is the horizontal coordinate of the array center; y0 is the vertical coordinate of the array center; z0 is the vertical coordinate of the array center; x is the horizontal coordinate of the sound source signal; y is the vertical coordinate of the sound source signal; z is the vertical coordinate of the sound source signal.

[0020] Preferably, in step S2, a sound wave receiving device is used to determine the distance difference Δd from the sound source signal to the microphone array element, specifically:

[0021] The relative time difference between the sound wave signal and the microphone array element in the sound wave receiving device is analyzed to obtain the time delay between the corresponding signal waveforms, and the microphone array element time difference Δt is extracted to obtain the distance difference between the sound source signal and the microphone array element:

[0022] Δd=v*Δt

[0023] Among them, Δd is the distance difference between the sound source and the microphone array element; v is the propagation speed of underwater ultrasound; Δt is the time difference of the microphone array element.

[0024] Preferably, the K-Means algorithm is used in step S3 to perform cluster analysis of water point cloud data as follows: the point cloud data or image feature data of the lidar is used as the data points to be clustered, and the data points with similar features are aggregated together according to the distance similarity metric, so as to classify the underwater target hull.

[0025] The second aspect of the present invention proposes an underwater hull positioning system based on a time delay and array topology underwater hull positioning method, which includes: a central processing subsystem, a target detection and positioning subsystem, a wireless transmission subsystem and a detection center subsystem;

[0026] The input end of the central processing subsystem is electrically connected to the output end of the target detection and positioning subsystem through a wire; the output end of the central processing subsystem is electrically connected to the input end of the wireless transmission subsystem through a wire, and the wireless transmission subsystem realizes a bidirectional connection with the detection center subsystem through wireless;

[0027] The target detection and positioning subsystem includes a detection unit and a data processing unit; the detection unit includes a sound wave transmitting device and a sound wave receiving device, the output end of which is electrically connected to the input end of the serial communication module through a wire, and the output end of the serial communication module is electrically connected to the input end of the data processing unit through a wire; the output end of the data processing unit is electrically connected to the input end of the feedback module through a wire.

[0028] Preferably, the detection unit includes a laser radar, a camera and a transmitting transducer, and the output end of the laser radar is electrically connected to the input end of the clustering module through a wire.

[0029] Preferably, the data processing unit comprises a microprocessor, and an input end of the microprocessor is electrically connected to an output end of the depth information acquisition module through a wire;

[0030] The input end of the microprocessor is electrically connected to the input end of the underwater acoustic signal processor through a wire, and the input end of the underwater acoustic signal processor is electrically connected to the output end of the signal processor through a wire;

[0031] The output end of the microprocessor is electrically connected to the input end of the positioning calculation module through a wire, the output end of the positioning calculation module is electrically connected to the input end of the distance acquisition module through a wire, and the output end of the positioning calculation module is electrically connected to the input end of the coordinate positioning module through a wire.

[0032] Preferably, the input end of the signal processor is electrically connected to the output end of the sound wave receiving device through a wire.

[0033] Preferably, the input end of the depth information acquisition module is electrically connected to the output end of the radar data analysis module through a wire.

[0034] Preferably, the sound wave receiving device is provided with a microphone array evenly distributed along a straight line, comprising a total of n microphone array elements.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The present invention detects underwater target hulls through sound waves, and uses the delay algorithm and array topology structure in the time difference positioning algorithm to determine the position information of the underwater target hull; finally, cluster analysis is performed using the K-Means algorithm to identify the hull type, thereby providing an underwater target detection method with high recognition accuracy.

[0037] (2) The present invention uses laser radar, camera, transmitting transducer and underwater acoustic signal processor to identify and scan underwater targets, obtain underwater target position data, and quickly locate them, thereby reducing the workload of personnel and providing data guarantee for subsequent underwater maintenance operations.

[0038] (3) The present invention electrically connects the output end of the central processing subsystem to the input end of the wireless transmission subsystem through a wire, and the wireless transmission subsystem realizes a two-way connection with the detection center subsystem through wireless, and can send the specific positioning data information of the target to the detection center subsystem, thereby facilitating subsequent processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A control block diagram of the underwater hull positioning method based on time delay and array topology of the present invention;

[0040] Figure 2 It is a structural schematic diagram of the underwater hull positioning system of the present invention;

[0041] Figure 3 It is a schematic diagram of the structure of the target detection and positioning subsystem of the present invention;

[0042] Figure 4 It is a structural schematic diagram of the detection unit of the present invention;

[0043] Figure 5 It is a structural schematic diagram of the data processing unit of the present invention.

[0044] Main figure marks: 1. Central processing subsystem; 2. Target detection and positioning subsystem; 21. Detection unit; 211. Laser radar; 212. Camera; 213. Clustering module; 214. Transmitting transducer; 22. Serial communication module; 23. Data processing unit; 231. Microprocessor; 232. Depth information acquisition module; 233. Radar data analysis module; 234. Underwater acoustic signal processor; 235. Signal processor; 236. Sound wave receiving device; 237. Positioning calculation module; 238. Coordinate positioning module; 239. Distance acquisition module; 24 Feedback module; 3. Wireless transmission subsystem; 4. Detection center subsystem. DETAILED DESCRIPTION

[0045] The exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0046] The present invention provides an underwater hull positioning method based on time delay and array topology, such as Figure 1 As shown, the image data of the underwater target hull is obtained, sound waves are emitted for detection, and echoes are received; the sound wave signals received by the sound wave receiving device are analyzed and processed based on the time delay algorithm in the time difference positioning algorithm; an underwater three-dimensional space model is established, and the position information of the underwater target hull is determined according to the array topology structure; according to the position information of the underwater target hull, cluster analysis is performed to identify the hull type; it includes:

[0047] Step S1: Acquire image data of the underwater target hull, emit sound waves for detection, and receive echoes; obtain image data of the underwater target hull by shooting with a camera, use a sound wave transmitting device to detect the underwater target hull, obtain hull depth information, and use a sound wave receiving device to receive the sound wave signal reflected back from the surface of the underwater target hull, wherein the camera can be a wide-angle camera.

[0048] Step S2: Analyze and process the sound wave signal received by the sound wave receiving device based on the time delay algorithm in the time difference positioning algorithm.

[0049] The sound wave receiving device is provided with a microphone array along a uniformly distributed straight line. The sound wave receiving device is used to determine the distance difference Δd between the sound source signal and the microphone array element. The relative time difference between the sound wave signal and the microphone array element in the sound wave receiving device is analyzed to obtain the time delay between the corresponding signal waveforms. The microphone array element time difference Δt is extracted to obtain the distance difference between the sound source signal and the microphone array element:

[0050] Δd=v*Δt;

[0051] Among them, Δd is the distance difference between the sound source and the microphone array element; v is the propagation speed of underwater ultrasound; Δt is the time difference of the microphone array element.

[0052] Set the first microphone array element in the sound wave receiving device as the reference point, and obtain the sound wave signal received by the nth microphone array element at time k:

[0053]

[0054] Among them, y n (k) is the signal finally received by the nth array element at time k; α n (n=1,2,...,N) is the attenuation of the signal during propagation; s is the sound source signal; k is the time parameter; t is the propagation time from the sound source to the first array element; τ n1 is the signal delay difference received by the first microphone array element and the second microphone array element; v n (k) is the additive noise received on the nth array element; F n (τ) is the signal delay function between the nth array element and the first array element; x n (k) is the amount by which the nth array element changes with time k.

[0055] Step S3: Establish an underwater three-dimensional space model and determine the position information of the underwater target hull according to the array topology structure.

[0056] According to the geometric relationship between the sound source signal and the array obtained in step S2, the direction angle and distance of the sound wave signal are determined, the axial direction of the array is set as the reference direction, and the angle formed by the sound source signal, the line connecting the center of the array and the axial direction of the array is calculated and used as the direction angle of the sound wave signal; the distance L of the underwater target hull is obtained by using the distance formula between two points in space:

[0057]

[0058] Among them, L is the distance of the underwater target hull; x0 is the horizontal coordinate of the array center; y0 is the vertical coordinate of the array center; z0 is the vertical coordinate of the array center; x is the horizontal coordinate of the sound source signal; y is the vertical coordinate of the sound source signal; z is the vertical coordinate of the sound source signal.

[0059] Step S4: According to the position information of the underwater target hull identified in step S3, the laser radar 211 is used to scan the water area where the underwater target hull is located to obtain water area point cloud data, and after noise elimination and coordinate conversion, the K-Means algorithm is used to perform cluster analysis on the water area point cloud data, and the hull type is identified, and the obtained underwater target hull data is sent to the detection center subsystem. The K-Means algorithm is used to perform cluster analysis on the water area point cloud data, specifically: the point cloud data or image feature data of the laser radar 211 is used as the data points to be clustered, and the data points with similar features are aggregated together according to the distance similarity metric standard, so as to classify the underwater target hull.

[0060] The second aspect of the embodiment of the present invention proposes an underwater hull positioning system based on a time delay and array topology underwater hull positioning method, such as Figure 2 The figure shows a schematic diagram of the structure of the underwater hull positioning system of the present invention; it comprises: a central processing subsystem 1, a target detection and positioning subsystem 2, a wireless transmission subsystem 3 and a detection center subsystem 4.

[0061] The input end of the central processing subsystem 1 is electrically connected to the output end of the target detection and positioning subsystem 2 through a wire; the output end of the central processing subsystem 1 is electrically connected to the input end of the wireless transmission subsystem 3 through a wire, and the wireless transmission subsystem 3 is bidirectionally connected to the detection center subsystem 4 through wireless. The central processing subsystem 1 is referred to as CPU, which is the computing core and control core of a computer and the final execution unit of information processing and program operation.

[0062] like Figure 3 The structure diagram of the target detection and positioning subsystem of the present invention is shown; the target detection and positioning subsystem 2 includes a detection unit 21 and a data processing unit 23; the detection unit 21 includes a sound wave transmitting device and a sound wave receiving device, the output end of the detection unit 21 is electrically connected to the input end of the serial communication module 22 through a wire, and the output end of the serial communication module 22 is electrically connected to the input end of the data processing unit 23 through a wire; the output end of the data processing unit 23 is electrically connected to the input end of the feedback module 24 through a wire.

[0063] like Figure 4 It is a schematic diagram of the structure of the detection unit of the present invention; the detection unit 21 includes a laser radar 211, a camera 212 and a transmitting transducer 214, and the output end of the laser radar 211 is electrically connected to the input end of the clustering module 213 through a wire.

[0064] like Figure 5The data processing unit 23 of the present invention is shown as a structural schematic diagram. The data processing unit 23 includes a microprocessor 231, the input end of the microprocessor 231 is electrically connected to the output end of the depth information acquisition module 232 through a wire; the input end of the microprocessor 231 is electrically connected to the input end of the underwater acoustic signal processor 234 through a wire, and the input end of the underwater acoustic signal processor 234 is electrically connected to the output end of the signal processor 235 through a wire; the output end of the microprocessor 231 is electrically connected to the input end of the positioning calculation module 237 through a wire, and the output end of the positioning calculation module 237 is electrically connected to the input end of the distance acquisition module 239 through a wire, and the output end of the positioning calculation module 237 is electrically connected to the input end of the coordinate positioning module 238 through a wire.

[0065] The input end of the signal processor 235 is electrically connected to the output end of the sound wave receiving device 236 through a wire. The input end of the depth information acquisition module 232 is electrically connected to the output end of the radar data analysis module 233 through a wire; the sound wave receiving device is provided with a uniformly distributed linear microphone array, including a total of n microphone array elements.

[0066] The beneficial effects of the present invention are as follows: the embodiment of the present invention detects the underwater target hull through sound waves, and uses the delay algorithm and array topology structure in the time difference positioning algorithm to determine the position information of the underwater target hull; finally, cluster analysis is performed by using the K-Means algorithm to identify the hull type; the underwater target hull is identified and scanned by a laser radar, a camera, a transmitting transducer and an underwater acoustic signal processor to obtain the underwater target position data, and a two-way connection is achieved through wireless and a detection center subsystem, and the specific positioning data information of the target is sent to the detection center subsystem, which reduces the workload of personnel and provides guarantee for subsequent underwater maintenance operations.

[0067] The embodiments described above are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for underwater hull positioning based on time delay and array topology, characterized in that: It includes: S1: Acquire image data of underwater target hull, transmit sound waves for detection, and receive echoes; The image data of the underwater target ship hull is obtained by shooting with a camera, the underwater target ship hull is detected by an acoustic wave transmitting device to obtain the depth information of the hull, and the acoustic wave receiving device is used to receive the acoustic wave signal reflected back from the surface of the underwater target ship hull; S2: Analyze and process the sound wave signal received by the sound wave receiving device based on the time delay algorithm in the time difference positioning algorithm; The sound wave receiving device is used to determine the distance difference Δd from the sound source signal to the microphone array element. The first microphone array element in the sound wave receiving device is set as the reference point, and the sound wave signal received by the nth microphone array element at time k is obtained as follows: y n (k)=a n s(kt-τ n1 )+v n (k) =α n s[k-t-F n (τ)]+v n (k) =x n (k)+v n (k) Among them, y n (k) is the signal finally received by the nth array element at time k; α n (n=1,2,...,N) is the attenuation of the signal during propagation; s is the sound source signal; k is the time parameter; t is the propagation time from the sound source to the first array element; τ n1 is the signal delay difference received by the first microphone array element and the second microphone array element; v n (k) is the additive noise received on the nth array element; F n (τ) is the signal delay function between the nth array element and the first array element; x n (k) is the amount of change of the nth array element over time k; S3: Establish an underwater three-dimensional space model and determine the position information of the underwater target hull according to the array topology structure; Determine the direction angle and distance of the sound wave signal according to the geometric relationship between the sound source signal and the array obtained in step S2, set the axial direction of the array as the reference direction, calculate the angle formed by the sound source signal, the line connecting the center of the array and the axial direction of the array, and use it as the direction angle of the sound wave signal; S4: According to the position information of the underwater target hull identified in step S3, the water area where the underwater target hull is located is scanned by a laser radar to obtain water area point cloud data. After noise elimination and coordinate conversion, the K-Means algorithm is used to perform cluster analysis on the water area point cloud data to identify the hull type, and the obtained underwater target hull data is sent to the detection center subsystem.

2. The underwater hull positioning method based on time delay and array topology according to claim 1 is characterized in that: Using the distance formula between two points in space, the distance L of the underwater target hull is: Among them, L is the distance of the underwater target hull; x0 is the horizontal coordinate of the array center; y0 is the vertical coordinate of the array center; z0 is the vertical coordinate of the array center; x is the horizontal coordinate of the sound source signal; y is the vertical coordinate of the sound source signal; z is the vertical coordinate of the sound source signal.

3. The underwater hull positioning method based on time delay and array topology according to claim 1 is characterized in that: In step S2, a sound wave receiving device is used to determine the distance difference Δd from the sound source signal to the microphone array element, which is specifically: The relative time difference between the sound wave signal and the microphone array element in the sound wave receiving device is analyzed to obtain the time delay between the corresponding signal waveforms, and the microphone array element time difference Δt is extracted to obtain the distance difference between the sound source signal and the microphone array element: Δd=v*Δt Among them, Δd is the distance difference between the sound source and the microphone array element; v is the propagation speed of underwater ultrasound; Δt is the time difference of the microphone array element.

4. The underwater hull positioning method based on time delay and array topology according to claim 1 is characterized in that: In step S3, the K-Means algorithm is used to perform cluster analysis on the water point cloud data. Specifically, the point cloud data or image feature data of the lidar is used as the data points to be clustered, and the data points with similar features are aggregated together according to the distance similarity metric, so as to classify the underwater target hull.

5. An underwater hull positioning system according to the underwater hull positioning method based on time delay and array topology according to any one of claims 1 to 4, characterized in that: It includes: Central processing subsystem, target detection and positioning subsystem, wireless transmission subsystem and detection center subsystem; The input end of the central processing subsystem is electrically connected to the output end of the target detection and positioning subsystem through a wire; the output end of the central processing subsystem is electrically connected to the input end of the wireless transmission subsystem through a wire, and the wireless transmission subsystem realizes a bidirectional connection with the detection center subsystem through wireless; The target detection and positioning subsystem includes a detection unit and a data processing unit; the detection unit includes a sound wave transmitting device and a sound wave receiving device, the output end of the detection unit is electrically connected to the input end of the serial communication module through a wire, the output end of the serial communication module is electrically connected to the input end of the data processing unit through a wire; the output end of the data processing unit is electrically connected to the input end of the feedback module through a wire.

6. The underwater hull positioning system according to claim 5, characterized in that: The detection unit includes a laser radar, a camera and a transmitting transducer, and the output end of the laser radar is electrically connected to the input end of the clustering module through a wire.

7. The underwater hull positioning system according to claim 5, characterized in that: The data processing unit includes a microprocessor, and the input end of the microprocessor is electrically connected to the output end of the depth information acquisition module through a wire; The input end of the microprocessor is electrically connected to the input end of the underwater acoustic signal processor through a wire, and the input end of the underwater acoustic signal processor is electrically connected to the output end of the signal processor through a wire; The output end of the microprocessor is electrically connected to the input end of the positioning calculation module through a wire, the output end of the positioning calculation module is electrically connected to the input end of the distance acquisition module through a wire, and the output end of the positioning calculation module is electrically connected to the input end of the coordinate positioning module through a wire.

8. The underwater hull positioning system according to claim 7, characterized in that: The input end of the depth information acquisition module is electrically connected to the output end of the radar data analysis module through a wire.

9. The underwater hull positioning system according to claim 5, characterized in that: The input end of the signal processor is electrically connected to the output end of the sound wave receiving device through a wire.

10. The underwater hull positioning system according to claim 5, characterized in that: The sound wave receiving device is provided with a microphone array evenly distributed along a straight line, which comprises n microphone array elements in total.

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