Point cloud data-based submarine cable exposed pipe section detection method and system

Abstract

The invention discloses a submarine cable exposed pipe section detection method and system based on point cloud data, and relates to a submarine cable detection method. At present, the method for detecting the exposed pipe section of the submarine cable lacks an efficient automatic quantitative analysis means, depends on manual analysis, is complex in processing process, and is difficult to realize real-time monitoring and accurate evaluation. The method comprises the following steps: firstly, separating a submarine cable part and a seabed part from seabed point cloud data; performing profile processing on the point cloud; for the submarine cable part, extracting the center of a continuous submarine cable pipe section, calculating the trend of the submarine cable, and extracting the height of the submarine cable; for the seabed part, the seabed height is extracted after seabed reconstruction and is compared with the submarine cable height, and the occurrence condition is quantitatively calculated. According to the technical scheme, a submarine cable point cloud data processing method, a submarine cable section fitting method and a quantitative occurrence state calculation method are provided, the abnormal states of submarine cable exposure, suspension, displacement and the like can be detected, and key technical support is provided for submarine cable detection automation and intellectualization.

Description

Technical Field

[0001] The invention relates to a method for detecting submarine cables, and in particular to a method for detecting exposed submarine cable sections based on point cloud data. Background Art

[0002] As an important part of power transmission in offshore wind farms, the safe and reliable operation of submarine cables is crucial to ensuring the stability of offshore wind farm systems. Submarine cables are usually buried or laid deep in the seabed, directly undertaking the task of transmitting electricity from offshore wind turbines to land. Due to the complex working environment of submarine cables and full of unpredictable factors, such as changes in seabed geology, seawater flow, and seabed animal activities, submarine cables are very prone to damage, exposure, or displacement. These problems may directly lead to cable damage or power transmission interruption, thereby affecting the stable operation of the entire wind farm. Therefore, how to effectively monitor the operation of submarine cables, especially when the cables are exposed or in abnormal conditions, timely detection and taking measures are the key to ensuring the safe operation of submarine cables.

[0003] At present, the technology for detecting the exposed pipe section of submarine cables generally uses underwater three-dimensional sonar, multi-beam depth sounding sonar and other equipment. These devices can obtain three-dimensional point cloud data of the seabed and submarine cables by scanning the seabed area. These point cloud data provide basic information for detecting submarine cables. Based on these point cloud data, traditional submarine cable detection methods usually identify the exposed pipe sections of cables through manual analysis or simple qualitative evaluation. However, this method has many problems, which are mainly reflected in the following aspects: 1. Qualitative detection is the main method, lacking quantitative analysis: Most existing methods use qualitative evaluation based on point clouds, which can only provide a rough judgment on the existence status of submarine cables (such as whether they are exposed, suspended, etc.), and lack precise quantitative calculations, which makes the detection of submarine cable status often not accurate enough.

[0004] 2. Strong dependence on manual analysis: Many current point cloud data-based detection methods rely on manual analysis of data segment by segment, which is labor-intensive, inefficient, and prone to human errors. Especially in complex seabed environments, the accuracy and real-time performance of manual analysis are difficult to guarantee.

[0005] 3. Low level of automation: Although some automated detection technologies have been proposed, most technologies are still in the preliminary stage and cannot process large amounts of point cloud data efficiently and accurately. Especially in the dynamically changing seabed environment, existing technologies are difficult to cope with complex situations.

[0006] Therefore, with the increasing application of submarine cables and the increasingly complex submarine environment, there is an urgent need for a new method for detecting exposed sections of submarine cables based on point cloud data, which can improve the accuracy and efficiency of automated detection, and can quantitatively evaluate the existence status of submarine cables, reduce manual intervention, provide more reliable monitoring results, and provide technical guarantee for the safe and stable operation of offshore wind farms. Summary of the invention

[0007] The technical problem to be solved and the technical task proposed by the present invention are to improve and perfect the existing technical solutions, and provide a method and system for detecting exposed pipe sections of submarine cables based on point cloud data, so as to achieve the purpose of efficient and automatic detection by quantitatively analyzing the occurrence state of submarine cables. To this end, the present invention adopts the following technical solutions.

[0008] A method for detecting exposed pipe sections of submarine cables based on point cloud data comprises the following steps: 1) Obtain seabed point cloud data P, and separate submarine cable point cloud data PC and seabed terrain point cloud data PG from the seabed point cloud data using the RANSAC method; 2) Slice the submarine cable point cloud data PC and the seabed terrain point cloud data PG to obtain the submarine cable profile set and the terrain profile set; 3) Perform ellipse fitting on the submarine cable point cloud profile data in the submarine cable profile set to extract the center of the submarine cable (x c ,y c ) and the cable height h pipe ; Perform polynomial fitting on the seafloor topography point cloud profile data in the topographic profile set to obtain the seafloor height h seabed ; 4) According to the height h of the submarine cable pipe and seafloor height h seabed The difference E of the cable is used to quantitatively calculate the existence status of the submarine cable. If E≤D, it means that the submarine cable is exposed or completely exposed. If E>D, it means that the submarine cable is suspended, where D is the diameter of the submarine cable.

[0009] This technical solution can quantitatively calculate the existence state of the submarine cable by performing profile slicing, ellipse fitting and polynomial fitting on the point cloud data of the submarine cable and the seabed, overcoming the limitations of traditional qualitative analysis and providing more accurate and reliable detection results. It greatly improves the automation level of submarine cable detection, reduces the dependence on manual analysis, can quickly and efficiently process large-scale point cloud data, and improves the efficiency and accuracy of detection. By ellipse fitting the submarine cable profile data and polynomial fitting the seabed terrain data, the geometric characteristics of the submarine cable and the height information of the seabed can be accurately extracted, especially when dealing with curved or complex submarine cables, with excellent fitting accuracy. It can accurately identify abnormal states such as exposure, suspension or displacement of the submarine cable, timely discover potential safety hazards, and ensure the safety and stability of the submarine cable. This method can adapt to complex submarine environments. In the monitoring of submarine cables, it can effectively cope with different submarine terrains and submarine cable configurations, and has a wide range of application scenarios.

[0010] As a preferred technical means: in step 2), by setting the slicing plane and the auxiliary plane, the section point cloud set is obtained by using the intersection of the point cloud and the slicing plane, and the section point cloud is projected to obtain the section data point set corresponding to the slicing plane.

[0011] By setting auxiliary planes and adjusting the slice thickness, this technical solution can effectively increase the point cloud density of each slice, avoid incomplete profile data or large errors caused by sparse point clouds, and thus improve the accuracy and reliability of profile point cloud data. Compared with traditional methods, the combination of slicing planes and auxiliary planes can more accurately obtain profile point cloud sets, avoid data omissions or errors that may be caused by a single slicing plane, and ensure that the profile data is more in line with the actual submarine cable and submarine structure morphology. Through projection processing, the error of profile data in three-dimensional space can be reduced, making the profile data smoother and more consistent, avoiding interference caused by factors such as undulating submarine terrain and changes in submarine cable morphology, and improving the stability and reliability of detection. Through projection processing of profile point clouds, this method allows different submarine terrains and submarine cable configurations to be more accurately expressed, can adapt to different environmental changes, and has greater flexibility and universality. This technical solution uses the strategy of slicing planes and auxiliary planes to make the slicing and processing of point cloud data more efficient, reduce a large amount of unnecessary data calculations, and improve the efficiency of overall data processing, especially in the processing of large-scale point cloud data. It has obvious advantages.

[0012] As a preferred technical means: the slicing process of step 2) includes the following: 2.1) Given point cloud data P{P i |i=1,2,3,...,n} and a set of slice planes {S i |i=1,2,3,...,m}, for each slice plane Si Generate two symmetrical auxiliary planes S i ' and S i ", the distance between the two auxiliary planes is the slice thickness σ, and S i ' and S i The point between them is taken as the slice plane S i The corresponding contour point cloud set; 2.2) According to the slice plane S i The normal vector and plane equation of the point cloud data P are traversed to determine the points on the slice plane S. i The set of points on ; 2.3) Set the slice plane S i The point set on the slice plane is projected onto the slice plane to obtain the slice plane S i The corresponding profile data point set.

[0013] By providing each slice plane S i Generate two symmetrical auxiliary planes S i ' and S i ", and select point cloud data between them as the contour point cloud set, which can effectively improve the resolution of point cloud data. The use of auxiliary planes ensures the controllability of the slice thickness σ, making the capture of details more accurate, thereby providing higher quality data for subsequent fitting and analysis. The double-layer screening strategy of slice planes and auxiliary planes can ensure that each slice can obtain richer and more accurate point cloud data, avoid potential data loss or errors caused by only a single slice plane, and ensure that each profile can fully represent the actual submarine cable or submarine terrain characteristics. In step 2.1), by controlling the slice thickness σ and the distance between the auxiliary planes, it can be flexibly adjusted for different submarine terrains, submarine cable structures and environmental changes to meet different actual needs, so that the scheme can be widely adapted to different detection scenarios, whether in flat seabed or complex seabed terrain, it can be stably and effectively executed. Step The slicing plane and point cloud projection method in steps 2.2) and 2.3) simplifies the point cloud processing process, avoids the complex three-dimensional space calculations that may be required in traditional methods, and can significantly reduce the computational burden while ensuring data accuracy, improve processing efficiency, and effectively save computing resources and time, especially when processing large-scale point cloud data. By projecting the point set on the slicing plane, the uncertainty caused by point cloud data noise, irregular seabed topography, etc. can be eliminated, the stability of the profile data can be improved, and the morphology of the submarine cable and the seabed topography can be more accurately reflected in the profile data, thereby ensuring the reliability of the analysis results. Through projection processing, not only can the point cloud be accurately mapped to the slicing plane, but also its structural information in the slicing plane can be better preserved, the details of the profile data can be enhanced, and the quantitative analysis of the occurrence of submarine cables, seabed morphology, etc. can be more accurate and comprehensive.

[0014] As a preferred technical means: in step 2.2), according to the slice plane S i The normal vector , plane equation n1x+n2y+n3z+n0=0, traverse each point P in the point cloud i , if satisfied , which means that the point is on the slice plane, and the slice plane S is obtained. i Point set on ; In step 2.3), the point set on the slice plane is projected into the slice plane. For any P i,j , let its projection point in the slice plane be ,use With the slice plane S i The vertical projection relationship is given by the following formula:

[0015] Calculate the slice plane S i The corresponding profile data point set {q i,j |j=1,2,...,N}; where It is a pointer To its projection point Vector.

[0016] In step 2.2), the slice plane S i The relationship between the normal vector of the point cloud data and each point Pi can accurately determine which points are on the slice plane. To determine whether a point belongs to the slice plane, we can ensure that only qualified points are selected, effectively filter out the noise data that does not meet the conditions, and ensure the accuracy and reliability of the data. By traversing the point cloud data and screening the points according to the plane equation, step 2.2) simplifies the point cloud selection process in the traditional method, improves the calculation efficiency, and can quickly locate the point set on the slice plane without relying on complex spatial analysis or lengthy calculation processes.

[0017] Step 2.3) projects the point set on the slice plane into the slice plane, and uses a projection relationship perpendicular to the slice plane to process the point cloud, ensuring the accuracy of the projection result, while avoiding errors caused by the complexity or noise of the point cloud, and efficiently and accurately mapping each point into the slice plane, thereby ensuring the quality of the profile data point set. Using the projection relationship between the slice plane and the point cloud point, the geometric projection formula is used in step 2.3), which simplifies the traditional three-dimensional data conversion process, can quickly obtain the projection result of each point, significantly reduces the amount of calculation, and is particularly suitable for processing large-scale point cloud data, which helps to improve the efficiency of data processing. By using a clear mathematical formula to describe the relationship between the slice plane and the point cloud point, the projection result of the point cloud data on the slice plane is more stable and reliable, ensuring that in a complex submarine environment, no matter how the submarine cable or submarine topography changes, step 2.3) can obtain a high-quality profile data point set, thereby improving the accuracy of subsequent analysis results. This method can flexibly adapt to different types of submarine environments, including the undulating changes of the submarine topography, the different layout of the submarine cable, etc. No matter how the submarine environment changes, the processing method based on the slice plane and the projection relationship can ensure data accuracy and has strong adaptability. The profile data point set obtained in step 2.3) can be used to easily carry out subsequent fitting, analysis and detection, such as submarine cable status assessment, seabed topography analysis, etc. The accuracy and completeness of the profile data point set provide a reliable data basis for subsequent quantitative analysis and judgment.

[0018] As a preferred technical means: Step 3) includes: 3.1) Ellipse fitting of submarine cable point cloud profile data: Assuming that the cross section of the submarine cable is approximately an ellipse, the cross section point set of the submarine cable {q i (x i ,y i )|i=1,2,...,N} is the slice plane data of the submarine cable point cloud; The fit is done using the general form of the equation of an ellipse, which is as follows:

[0019] Among them, A, B, C, D, E, and F are fitting parameters, and Δ is the discriminant; For each point (x i ,y i ), calculate its algebraic distance d(x,y) to the ellipse, which is:

[0020] Use the least squares method to fit the parameters of the ellipse, with the goal of minimizing the sum of the algebraic distances of all points:

[0021] in, , is the parameter vector of the ellipse equation; , for the point (x i ,y i )’s feature vector; Solve the geometric parameters of the ellipse, including the semi-major axis a, the semi-minor axis b, the coordinates of the center of the ellipse (x c ,y c ), the angle between the major axis and the minor axis; the calculation formulas for these parameters are as follows:

[0022] Calculating the height of a submarine cable , which is the longitudinal coordinate of the center of the cable section plus the length of the semi-minor axis; 3.2) Polynomial fitting of terrain point cloud profile data: Perform polynomial fitting on the terrain profile point cloud data near the submarine cable; select the highest point of the fitting segment from the fitted polynomial as the seabed height h seabed , which is used for the subsequent calculation of the submarine cable existence status.

[0023] Step 3.1 assumes that the cross section of the submarine cable is approximately an ellipse, and uses the ellipse equation for fitting, which can accurately describe the geometric shape of the submarine cable. This assumption is often applicable in practical applications, especially since submarine cables are usually cylindrical and their cross sections are approximately elliptical; through least squares fitting, the precise geometric parameters of the submarine cable can be obtained, such as the semi-major axis, semi-minor axis, center coordinates, and the inclination angle of the ellipse. By minimizing the sum of algebraic distances, the accuracy of the fitting can be effectively improved and the error can be reduced; this makes the fitting results more consistent with the geometric characteristics of the actual submarine cable and improves the accuracy of the detection.

[0024] The fitted ellipse geometric parameters (such as semi-major axis, semi-minor axis, ellipse center, angle, etc.) can accurately describe the geometric shape of the submarine cable; the calculated parameters ensure that the calculation of the submarine cable height is more accurate, and provide reliable data for the subsequent analysis of the submarine cable's existence status. Using the least squares method to optimize the fitting process can effectively avoid error accumulation, and by optimizing the cost function, the geometric model of the submarine cable is more consistent with the actual situation, improving the fitting accuracy.

[0025] Step 3.2 uses polynomial fitting to model the seabed topography, which can better reflect the complex undulations of the seabed; polynomial fitting can flexibly adjust parameters to adapt to different types of terrain features and improve the accuracy of the seabed height. By selecting the highest point in the fitting polynomial as the seabed height, the seabed height at the location of the submarine cable can be accurately represented, effectively avoiding interference from factors such as local depressions on the seabed, and ensuring that the judgment of the submarine cable's existence status is more reliable.

[0026] This method reduces the need for manual analysis, improves detection efficiency, and avoids the possibility of human misjudgment through automated fitting and calculation. Especially when faced with a large amount of point cloud data, automated processing can significantly improve processing speed and accuracy. Regardless of the complexity of the seabed terrain, this method can automatically adapt and fit, allowing the solution to work reliably in different sea environments and adapt to different submarine cable layouts and terrain conditions.

[0027] By using mathematical models and optimization algorithms, large-scale point cloud data can be effectively processed; seabed point cloud data is usually huge in size. The use of this solution can ensure the accuracy of the processing results while maintaining computing efficiency and adapt to the processing needs of large-scale data sets.

[0028] By accurately calculating the difference E between the height of the submarine cable and the height of the seabed, the existence status of the submarine cable can be quantitatively judged, providing quantitative data with more reference value than traditional qualitative analysis; making the detection results more objective and scientific, and providing data support for subsequent maintenance and management.

[0029] The precise submarine cable geometric parameters and seabed height information provided by this solution can provide reliable data support for subsequent intelligent decision-making systems; for example, the system can automatically identify whether the submarine cable needs to be reinforced, repaired or re-laid based on the calculated state data, thereby improving the intelligence level of submarine cable management.

[0030] Another object of the present invention is to provide a submarine cable exposed pipe section detection system based on point cloud data, the system applying the aforementioned submarine cable exposed pipe section detection method based on point cloud data, the system comprising: Point cloud data acquisition module, used to acquire seabed point cloud data; A point cloud separation module is used to separate the submarine cable point cloud data PC and the seabed terrain point cloud data PG from the seabed point cloud data by using the RANSAC method; The slicing module is used to slice the submarine cable point cloud data PC and the seabed terrain point cloud data PG to obtain the submarine cable profile set and the terrain profile set; Fitting module for: Perform ellipse fitting on the submarine cable point cloud profile data in the submarine cable profile set to extract the center of the submarine cable (x c ,y c ) and the cable height h pipe ; Perform polynomial fitting on the seafloor topography point cloud profile data in the topographic profile set to obtain the seafloor height h seabed ; The existence state calculation module is used to calculate the cable height h seabed and seafloor height h seabedThe difference E is used to quantitatively calculate the existence status of the submarine cable and determine whether the submarine cable is exposed or suspended.

[0031] This technical solution can efficiently and accurately detect exposed sections of submarine cables through automated data processing, precise fitting algorithms, and quantitative occurrence state assessment. The system has high adaptability, low error rate, and good scalability, providing reliable technical support for the monitoring and maintenance of submarine cables. Specifically: Through the automated collaboration of multiple modules, the system automatically completes everything from data acquisition to occurrence state calculation, greatly reducing manual intervention; it not only improves detection efficiency, but also avoids errors that may be caused by human operation. The system can efficiently process a large amount of point cloud data, supports large-scale data set processing, and is suitable for submarine cable detection tasks of different scales.

[0032] The RANSAC method is used to accurately separate the submarine cable point cloud data and the seabed terrain point cloud data, ensuring that subsequent analysis only targets relevant data, thereby improving the accuracy of the analysis; the submarine cable profile data can be accurately described by ellipse fitting, especially when the submarine cable is in a cylindrical shape. This method can ensure the accuracy of height calculation; polynomial fitting of the seabed terrain point cloud data can better adapt to the complex and undulating seabed terrain, thereby obtaining a more accurate seabed height hseabed.

[0033] The system can quantitatively evaluate the existence status of submarine cables by calculating the difference between the height of the submarine cable and the height of the seabed; compared with the traditional qualitative analysis method, this quantitative method is more scientific and objective, and can provide reliable data support for the subsequent maintenance and management of submarine cables. By setting the threshold of the difference E and the diameter D of the submarine cable, the system can automatically determine whether the submarine cable is exposed or suspended, providing accurate decision support.

[0034] The system automatically completes the fitting of submarine cables and seabed topography and the calculation of the occurrence state through algorithms, reducing manual intervention and possible errors in the analysis process, and improving the accuracy and reliability of detection. By optimizing the ellipse fitting and polynomial fitting by the least squares method, the system can obtain more accurate geometric parameters, further improving the accuracy of the occurrence state calculation.

[0035] Regardless of the complexity of the seabed terrain, the system can automatically adapt through different fitting methods, can operate stably in a variety of seabed environments, and has strong adaptability.

[0036] The data provided by this system can not only be used for submarine cable existence status detection, but also for intelligent decision support systems. By combining with other monitoring systems, it can realize automatic monitoring, early warning and maintenance of submarine cables. The system can process point cloud data in real time and generate detection results. For exposed or suspended submarine cables, the system can quickly issue early warnings and provide timely decision support for subsequent repairs and maintenance.

[0037] Automated testing replaces the traditional manual testing process, greatly reducing labor costs, and can process large amounts of data in a short period of time, improving work efficiency. By reducing the number of manual on-site inspections of submarine cables, the safety risks caused by manual intervention are reduced, ensuring the safety of staff.

[0038] The system is capable of processing large-scale submarine cable point cloud data, adapting to submarine cable monitoring tasks of different scales, with high efficiency and high precision, and can operate stably in complex environments such as large offshore wind farms.

[0039] As a preferred technical means: the slicing module further includes: The contour point cloud set generating unit, given the point cloud data and a set of slice planes, generates two symmetrical auxiliary planes for each slice plane, and uses the points between the two auxiliary planes as the contour point cloud set corresponding to the slice plane; A point set determination unit, which traverses each point in the point cloud data according to the normal vector and plane equation of the slice plane, and determines the point set located on the slice plane; The projection processing unit projects the point set on the slice plane into the slice plane to obtain the section data point set corresponding to the slice plane.

[0040] Through the refined slicing module design, the system has higher accuracy and efficiency when processing submarine point cloud data. The refined processing of each submodule ensures the accurate extraction and processing of data, thereby improving the accuracy, robustness and efficiency of the entire detection system, and enhancing the scalability and adaptability of the system. These advantages enable this technical solution to better meet the needs of submarine cable exposed pipe section detection in complex submarine environments.

[0041] As a preferred technical means: the point set determination unit traverses each point in the point cloud according to the normal vector and plane equation of the slice plane. If a specific condition is met, it means that the point is on the slice plane, thereby obtaining the point set on the slice plane; the projection processing unit uses the vertical projection relationship to calculate the profile data point set corresponding to the slice plane through a specific formula.

[0042] This technical solution not only improves the accuracy of data processing through point screening and projection processing, but also enhances the efficiency, robustness and scalability of the system. Through this solution, effective information can be extracted and processed from point cloud data efficiently and accurately, improving the accuracy and automation level of submarine cable exposed pipe section detection.

[0043] As a preferred technical means: the fitting module further includes: The ellipse fitting unit assumes that the cross section of the submarine cable is approximately an ellipse, uses the general form of the ellipse equation to fit, solves the geometric parameters of the ellipse, and calculates the height of the submarine cable; The polynomial fitting unit performs polynomial fitting on the seabed topography point cloud profile data, and selects the highest point of the fitting segment from the fitted polynomial as the seabed height for the subsequent calculation of the submarine cable existence status.

[0044] By using the ellipse fitting unit and the polynomial fitting unit together, the system can efficiently and accurately complete the analysis of submarine cables and seabed topography. This technical solution not only improves the calculation accuracy, automation level and robustness, but also simplifies the data processing process, enhances the adaptability and scalability of the system, and provides strong technical support for the detection of exposed sections of submarine cables.

[0045] As a preferred technical means: it also includes an output module for outputting visual detection results and displaying the specific location and related parameters of the exposed pipe section of the submarine cable.

[0046] This technical solution provides an intuitive, convenient and efficient visualization method for the detection of exposed submarine cable sections. It not only enhances the readability of the test results, improves the timeliness and accuracy of decision-making, but also provides important support for subsequent monitoring, data analysis and report generation. Combined with other modules, the output module further enhances the overall performance of the system and promotes the automation, intelligence and precision of submarine cable monitoring. Specifically: The output module can display the test results in a graphical form, making the specific location and related parameters of the exposed cable section clear at a glance. Through intuitive charts or three-dimensional views, users can quickly understand the test results without complex numerical analysis or processing, which greatly improves the user experience. The visual interface clearly displays the location and other important information of the exposed cable section (such as cable height, seabed height difference, occurrence status, etc.) through colors, icons or marks, allowing relevant personnel to quickly identify problem areas and respond in a timely manner.

[0047] The output module helps operators quickly locate potential risk areas by displaying the specific location of exposed cable sections, thereby improving decision-making efficiency. During the inspection, maintenance and monitoring of submarine cables, it is possible to accurately understand which areas have potential safety hazards and formulate more targeted emergency plans. Visual detection results not only help decision makers identify current problems, but also provide data support for subsequent analysis and reporting. By displaying relevant parameters (such as cable height, seabed height, occurrence status, etc.), submarine cables at different locations can be further monitored and trend analyzed to ensure long-term safety and reliability.

[0048] The output module can automatically generate visual reports, reducing the time for manual processing and analysis. This is particularly important for regular inspections of submarine cables, as it can complete data analysis, report generation and visual display in a very short time, greatly improving work efficiency. By displaying the test results in real time, the output module can provide instant feedback to the monitoring system, allowing staff to take quick action when the submarine cable status is abnormal. For example, if the submarine cable is exposed or hanging in the air, the system can quickly notify the operator and display the specific location to ensure that the problem is handled in a timely manner.

[0049] The output module can display multi-dimensional detection results, such as the specific location of the submarine cable, changes in the height of the seabed, changes in the occurrence state, etc. The multi-angle presentation of these data helps to comprehensively evaluate the safety status of the submarine cable. It can help monitoring personnel gain a deeper understanding of the detection results and conduct a more comprehensive risk analysis than a single numerical report. By displaying the specific location and related parameters of the exposed section of the submarine cable, the output module helps inspectors grasp the status of the submarine cable as a whole, and can more effectively discover potential problem areas and avoid missing possible risk points.

[0050] The output module can also display historical monitoring data and compare it with the current test results. This function helps to determine whether the status of the submarine cable has changed and whether the detection trend is deteriorating. Historical data comparison can also help determine whether there are new potential risk areas and whether additional maintenance work is required. The output module can support long-term monitoring. Through the visualization of multiple test data, a trend chart with a long span is formed to help managers monitor the overall health of the submarine cable, discover potential risks and changing trends, and take measures in advance.

[0051] Visual inspection results are not only easy for operators to understand and process, but also suitable for communication with relevant departments or teams. Through charts, markings, data summaries, etc., the inspection situation can be reported to decision makers, management or related parties in a concise and clear manner, helping higher-level decision makers to grasp the information. This visual output module can be used as basic data for multi-party collaboration, making it easier for different teams or departments to share results and conduct subsequent joint analysis and work deployment. For example, the maintenance team of the submarine cable can quickly understand which areas need to be prioritized based on the visual data to ensure a quick response.

[0052] The output module can generate standardized test reports in a unified manner, reduce manual intervention, and ensure the standardization and consistency of reports. This is especially important for long-term and large-scale monitoring, which helps to ensure the quality of testing and the accuracy of reports. Automatically generated test reports are not only convenient for immediate viewing, but can also be archived for a long time for easy viewing and management in the future. The digital format of the report helps to improve the efficiency of data storage and management, and facilitates the retrieval and analysis of historical data in the future.

[0053] Beneficial effects: This technical solution significantly improves the detection accuracy and speed of exposed submarine cable sections through precise quantitative analysis and efficient automated detection, and is a key technological breakthrough in the field of submarine cable detection. 1. Through the processing of cross-section slicing, ellipse fitting and polynomial fitting of the point cloud data of the submarine cable and the seabed, the existence status of the submarine cable can be quantitatively calculated, overcoming the limitations of traditional qualitative analysis and providing more accurate and reliable detection results.

[0054] 2. This method greatly improves the automation level of submarine cable detection, reduces dependence on manual analysis, can quickly and efficiently process large-scale point cloud data, and improves the efficiency and accuracy of detection.

[0055] 3. By fitting the cable profile data with an ellipse and fitting the seabed topography data with a polynomial, the geometric characteristics of the cable and the height information of the seabed can be accurately extracted, especially when dealing with curved or complex cables, with excellent fitting accuracy.

[0056] 4. It can accurately identify abnormal conditions such as exposure, suspension or displacement of submarine cables, timely discover potential safety hazards, and ensure the safety and stability of submarine cables.

[0057] 5. This method can adapt to complex submarine environments. In the monitoring of submarine cables, it can effectively cope with different submarine terrains and submarine cable configurations and has a wide range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 is a flow chart of the present invention; Figure 2A schematic diagram of the existence status of a submarine cable detected by the present invention; Figure 3 A schematic diagram of the suspended section and exposed section of the submarine cable detected by the present invention; Figure 4 It is a schematic diagram of the principle of submarine cable point cloud slicing with thickness in the present invention; Figure 5 This is the point cloud processing effect of the submarine cable. DETAILED DESCRIPTION

[0059] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0060] Embodiment 1: like Figure 1 The figure shows a flow chart of a method for detecting exposed submarine cable sections based on point cloud data of the present invention. First, on the basis of obtaining the submarine point cloud data P, the submarine point cloud data P in the point cloud data is separated into submarine cable data PC and submarine terrain data PG by the RANSAC method; then, the submarine cable point cloud PC and the terrain point cloud PG are sliced ​​respectively to obtain the submarine cable profile set {qi} and the terrain profile set {g i Then, the fitting expression of the profile data points is completed to obtain the profile geometric parameters of the submarine cable and the ground approximate results, from which the set of submarine cable centers is calculated {C i}、The set of submarine cable heights {H i}、The collection of seafloor heights {G i}; Finally, the set of fitted submarine cable centers {C i}, which is the direction of the submarine cable; according to the set of submarine cable heights {H i}、The collection of seafloor heights {G i}The relationship between the two, quantitative detection of the occurrence status. Specifically includes the following steps: S1: Based on the seabed point cloud data P, the seabed point cloud data P in the point cloud data is separated into submarine cable data PC and seabed terrain data PG by the RANSAC method.

[0061] S2: Slice the submarine cable point cloud PC and the terrain point cloud PG respectively to obtain a submarine cable profile set and a terrain profile set.

[0062] The specific point cloud slicing method is: S2.1 Given point cloud data P{P i |i=1,2,3,...,n} and a set of slice planes {S i |i=1,2,3,...,m}, the distance between the slice planes is d, such as Figure 4 As shown; Since the actual points have no size, the point cloud density on the slice plane obtained by intersecting the point cloud and the slice plane is too small. This method introduces the slice width and increases the slice plane Si Generate two relative S on both sides i Auxiliary plane of symmetry S i ' and S i ". The distance between the two auxiliary planes is the slice thickness σ w , S i ' and S i The point between them is taken as the tangent plane S i The contour point cloud set in .

[0063] S2.2 Known slice plane S i The normal vector , plane equation ; Traverse each point P in the point cloud i , if satisfied , which means that the point is on the slice plane, and the slice plane S can be obtained. i Point set on .

[0064] S2.3 Project the point set on the slice plane into the slice plane: For any P i,j , let its projection point in the slice plane be ,use The vertical projection relationship with the slice plane Si can give the solution formula:

[0065] From this we can get the slice plane S i The corresponding profile data point set {q i,j |j=1,2,...,N}; where It is a pointer To its projection point Vector.

[0066] S3: Complete the fitting expression of the profile data points: For the profile data of the submarine cable point cloud, perform elliptic curve fitting and obtain the submarine cable center (x c ,y c )、Submarine cable height h pipe ; For the close-range ground profile data of the submarine cable, polynomial curve fitting is performed to obtain the seabed height h seabed .

[0067] The specific process of processing the profile point cloud in S3 is as follows: First, the slicing plane of the submarine cable point cloud is processed. The submarine cable can be approximated as a cylinder, and its slicing plane is approximately an ellipse. Therefore, an ellipse model is used for fitting. The general expression of the ellipse equation is:

[0068] The algebraic distance from any point (x, y) to the ellipse is d(x, y), then its expression is

[0069] make

[0070]

[0071] Then the ellipse equation can be expressed as ax = 0. Assume that the cable profile point set {q i (x i ,y i )|i=1,2,...,N}, the best fitting ellipse should be such that

[0072] In order to ensure that the result conforms to the elliptic equation, corresponding constraints need to be added when solving it using the least squares method. At this time, the general equation of the ellipse is solved. In order to analyze the submarine cable, the geometric parameters of the ellipse fitted to the cross-section surface need to be calculated, including the semi-major axis a, the semi-minor axis b, the coordinates of the center of the ellipse (x c ,y c ), the angle between the major axis and the minor axis, the specific solution formula is:

[0073] The height of the submarine cable .

[0074] Secondly, in order to analyze the existence of submarine cables, it is necessary to fit the ground profile data near the submarine cables to predict the estimated ground height. Here, a polynomial is used for fitting, and the highest point of the fitting segment is selected as the highest point of the seabed h seabed .

[0075] like Figure 5 As shown, the processing effect of the submarine cable point cloud processed by the present invention is shown, that is, elliptic curve fitting is performed on the profile data of the submarine cable point cloud; and polynomial curve fitting is performed on the close-range ground profile data of the submarine cable.

[0076] S4: Fit the coordinates of the center of the ellipse of each cable profile, which is the direction of the cable; according to the cable height h pipe 、Seafloor height h seabed , the existence state of the submarine cable can be quantitatively calculated, and E=h pipe -h seabed Assuming that the diameter of the submarine cable is D, when E<=D, it means that the submarine cable is partially or completely exposed. i >D, it means the submarine cable is suspended in the air.

[0077] like Figure 2 , Figure 3 As shown, it is a schematic diagram of the existence state of the submarine cable detected by the present invention, wherein a small part of the submarine cable exposed is the exposed pipe section, and the bottom of the submarine cable off the ground is the suspended pipe section.

[0078] Embodiment 2: A submarine cable exposed pipe section detection system based on point cloud data is provided. The system applies the aforementioned submarine cable exposed pipe section detection method based on point cloud data. The system comprises: 1. Point cloud data acquisition module, used to obtain seabed point cloud data.

[0079] 2. Point cloud separation module, used to separate submarine cable point cloud data PC and seabed terrain point cloud data PG from the seabed point cloud data through the RANSAC method.

[0080] 3. Slicing module, used to slice the submarine cable point cloud data PC and the seabed terrain point cloud data PG to obtain the submarine cable profile set and the terrain profile set.

[0081] The slicing module further comprises: The contour point cloud set generating unit, given the point cloud data and a set of slice planes, generates two symmetrical auxiliary planes for each slice plane, and uses the points between the two auxiliary planes as the contour point cloud set corresponding to the slice plane; The point set determination unit traverses each point in the point cloud data according to the normal vector and plane equation of the slice plane to determine the point set located on the slice plane; the point set determination unit traverses each point in the point cloud according to the normal vector and plane equation of the slice plane. If a specific condition is met, it means that the point is on the slice plane, thereby obtaining the point set on the slice plane; the projection processing unit uses the vertical projection relationship to calculate the profile data point set corresponding to the slice plane through a specific formula. Through point screening and projection processing, not only the accuracy of data processing is improved, but also the efficiency, robustness and scalability of the system are enhanced. Through this solution, effective information can be extracted and processed from point cloud data efficiently and accurately, and the accuracy and automation level of detection of exposed pipe sections of submarine cables can be improved.

[0082] The projection processing unit projects the point set on the slice plane into the slice plane to obtain the section data point set corresponding to the slice plane.

[0083] Through the refined slicing module design, the system has higher accuracy and efficiency when processing submarine point cloud data. The refined processing of each submodule ensures the accurate extraction and processing of data, thereby improving the accuracy, robustness and efficiency of the entire detection system, and enhancing the scalability and adaptability of the system. These advantages enable this technical solution to better meet the needs of submarine cable exposed pipe section detection in complex submarine environments.

[0084] 4. Fitting module, used for: Perform ellipse fitting on the submarine cable point cloud profile data in the submarine cable profile set to extract the center of the submarine cable (x c ,y c ) and the cable height h pipe ; Perform polynomial fitting on the seafloor topography point cloud profile data in the topographic profile set to obtain the seafloor height h seabed ; The fitting modules include: The ellipse fitting unit assumes that the cross section of the submarine cable is approximately an ellipse, uses the general form of the ellipse equation to fit, solves the geometric parameters of the ellipse, and calculates the height of the submarine cable; The polynomial fitting unit performs polynomial fitting on the seabed topography point cloud profile data, and selects the highest point of the fitting segment from the fitted polynomial as the seabed height for the subsequent calculation of the submarine cable existence status.

[0085] By using the ellipse fitting unit and the polynomial fitting unit together, the system can efficiently and accurately complete the analysis of submarine cables and seabed topography. This technical solution not only improves the calculation accuracy, automation level and robustness, but also simplifies the data processing process, enhances the adaptability and scalability of the system, and provides strong technical support for the detection of exposed sections of submarine cables.

[0086] 5. Existence state calculation module is used to calculate the cable height h seabed and seafloor height h seabed The difference E is used to quantitatively calculate the existence status of the submarine cable and determine whether the submarine cable is exposed or suspended.

[0087] 6. Output module, used to output visual detection results, display the specific location and related parameters of the exposed cable section. It provides an intuitive, convenient and efficient visualization method for the detection of exposed cable sections. It not only enhances the readability of the detection results, improves the timeliness and accuracy of decision-making, but also provides important support for subsequent monitoring, data analysis and report generation. Combined with other modules, the output module further enhances the comprehensive performance of the system and promotes the automation, intelligence and precision of submarine cable monitoring.

[0088] This embodiment can efficiently and accurately detect exposed sections of submarine cables through automated data processing, precise fitting algorithms, and quantitative occurrence state assessment. The system has high adaptability, low error rate, and good scalability, providing reliable technical support for monitoring and maintenance of submarine cables.

[0089] It is understandable that the detailed functional implementation of each of the above modules can be found in the introduction of the aforementioned method embodiment, and no further elaboration is made here.

[0090] Embodiment three: The functions that can be realized by a submarine cable exposed pipe section detection system based on point cloud data can all be completed by a computer device, and the computer device includes one or more processors and one or more memories, and at least one program code is stored in the one or more memories. The program code is loaded and executed by the one or more processors to implement the wireless signal processing method.

[0091] The processor takes out instructions from the memory one by one, analyzes the instructions, and then completes the corresponding operations according to the instruction requirements, generating a series of control commands, so that the various parts of the computer can automatically, continuously and coordinately move to become an organic whole, realize the input of programs, the input of data, and the calculation and output of results. The arithmetic operations or logical operations generated in this process are all completed by the operator; the memory includes a read-only memory (ROM), which is used to store computer programs, and a protection device is provided outside the memory.

[0092] Exemplarily, the computer program may be divided into one or more modules, one or more modules are stored in a memory and executed by a processor to implement the present invention. One or more modules may be a series of computer program instruction segments capable of implementing specific functions, and the instruction segments are used to describe the execution process of the computer program in a terminal device.

[0093] Those skilled in the art will understand that the description of the above service equipment is merely an example and does not constitute a limitation on the terminal equipment. It may include more or fewer components than described above, or a combination of certain components, or different components, for example, it may include input and output devices, network access devices, buses, etc.

[0094] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DP), application-specific integrated circuits (AIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the terminal device, and uses various interfaces and lines to connect various parts of the entire user terminal.

[0095] The above-mentioned memory can be used to store computer programs and / or modules. The above-mentioned processor realizes various functions of the above-mentioned terminal device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as an information collection template display function, a product information release function, etc.), etc.; the data storage area can store data created according to the use of the berth status display system (such as product information collection templates corresponding to different product types, product information that needs to be released by different product providers, etc.). In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (martMediaCard, MC), a secure digital (secureDigital, D) card, a flash card (FlahCard), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0096] If the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable medium. Based on this understanding, the present invention implements all or part of the modules / units in the above-mentioned embodiment system, and can also be completed by instructing the relevant hardware through a computer program. The above-mentioned computer program can be stored in a computer-readable medium, and the computer program can realize the functions of the above-mentioned various system embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The storage medium can be a computer-readable medium, and the computer-readable medium can include: any entity or device capable of carrying computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, RandomAcceMemory), electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0097] The above-mentioned method and system for detecting exposed pipe sections of submarine cables based on point cloud data are specific embodiments of the present invention, which have embodied the substantial characteristics and progress of the present invention. According to actual use needs and under the guidance of the present invention, equivalent modifications in shape, structure, etc. can be made to the system, which are all within the protection scope of this scheme.

Claims

1. A method for detecting exposed sections of submarine cables based on point cloud data, characterized in that The following steps are involved: 1) Obtain seabed point cloud data P, and separate submarine cable point cloud data PC and seabed terrain point cloud data PG from the seabed point cloud data using the RANSAC method; 2) Slice the submarine cable point cloud data PC and the seabed terrain point cloud data PG to obtain the submarine cable profile set and the terrain profile set; 3) Perform ellipse fitting on the submarine cable point cloud profile data in the submarine cable profile set to extract the center of the submarine cable (x c ,y c ) and the cable height h pipe ; Perform polynomial fitting on the seafloor topography point cloud profile data in the topographic profile set to obtain the seafloor height h seabed ; 4) According to the height h of the submarine cable pipe and seafloor height h seabed The difference E of the cable is used to quantitatively calculate the existence status of the submarine cable. If E≤D, it means that the submarine cable is exposed or completely exposed. If E>D, it means that the submarine cable is suspended, where D is the diameter of the submarine cable.

2. The method for detecting exposed submarine cable sections based on point cloud data according to claim 1, characterized in that: In step 2), by setting the slice plane and the auxiliary plane, the section point cloud set is obtained by using the intersection of the point cloud and the slice plane, and the section point cloud is projected to obtain the section data point set corresponding to the slice plane.

3. The method for detecting exposed submarine cable sections based on point cloud data according to claim 2, characterized in that: The slicing process in step 2) includes the following: 2.1) Given point cloud data P{P i |i=1,2,3,...,n} and a set of slice planes {S i |i=1,2,3,...,m}, for each slice plane S i Generate two symmetrical auxiliary planes S i ' and S i ", the distance between the two auxiliary planes is the slice thickness σ, and S i ' and S i The point between them is taken as the slice plane S i The corresponding contour point cloud set; 2.2) According to the slice plane S i The normal vector and plane equation of the point cloud data P are traversed to determine the points on the slice plane S. i The set of points on ; 2.3) Set the slice plane S i The point set on the slice plane is projected onto the slice plane to obtain the slice plane S i The corresponding profile data point set.

4. The method for detecting exposed submarine cable sections based on point cloud data according to claim 3 is characterized in that: In step 2.2), according to the slice plane S i The normal vector , plane equation n1x+n2y+n3z+n0=0, traverse each point P in the point cloud i , if satisfied , which means that the point is on the slice plane, and the slice plane S is obtained. i The point set on ; In step 2.3), the point set on the slice plane is projected into the slice plane. For any P i,j , let its projection point in the slice plane be ,use With the slice plane S i The vertical projection relationship is given by the following formula: Calculate the slice plane S i The corresponding profile data point set {q i,j |j=1,2,...,N}; where It is a pointer To its projection point Vector.

5. The method for detecting exposed submarine cable sections based on point cloud data according to claim 4, characterized in that: Step 3) Include: 3.1) Ellipse fitting of submarine cable point cloud profile data: Assuming that the cross section of the submarine cable is approximately an ellipse, the cross section point set of the submarine cable {q i (x i ,y i )|i=1,2,...,N} is the slice plane data of the submarine cable point cloud; The fit is done using the general form of the equation of an ellipse, which is as follows: Among them, A, B, C, D, E, and F are fitting parameters, and Δ is the discriminant; For each point (x i ,y i ), calculate its algebraic distance d(x,y) to the ellipse, which is: Use the least squares method to fit the parameters of the ellipse, with the goal of minimizing the sum of the algebraic distances of all points: in, , is the parameter vector of the ellipse equation; , for the point (x i ,y i )’s feature vector; Solve the geometric parameters of the ellipse, including the semi-major axis a, the semi-minor axis b, the coordinates of the center of the ellipse (x c ,y c ), the angle between the major axis and the minor axis; the calculation formulas for these parameters are as follows: Calculating the height of a submarine cable , which is the longitudinal coordinate of the center of the cable section plus the length of the semi-minor axis; 3.2) Polynomial fitting of terrain point cloud profile data: Perform polynomial fitting on the terrain profile point cloud data near the submarine cable; select the highest point of the fitting segment from the fitted polynomial as the seabed height h seabed , which is used for the subsequent calculation of the submarine cable existence status.

6. A submarine cable exposed pipe section detection system based on point cloud data, characterized in that: A method for detecting exposed pipe sections of submarine cables based on point cloud data as described in any one of claims 1 to 5 is applied, wherein the system comprises: Point cloud data acquisition module, used to acquire seabed point cloud data; A point cloud separation module is used to separate the submarine cable point cloud data PC and the seabed terrain point cloud data PG from the seabed point cloud data by using the RANSAC method; The slicing module is used to slice the submarine cable point cloud data PC and the seabed terrain point cloud data PG to obtain the submarine cable profile set and the terrain profile set; Fitting module for: Perform ellipse fitting on the submarine cable point cloud profile data in the submarine cable profile set to extract the center of the submarine cable (x c ,y c ) and the cable height h pipe ; Perform polynomial fitting on the seafloor topography point cloud profile data in the topographic profile set to obtain the seafloor height h seabed ; The existence state calculation module is used to calculate the cable height h seabed and seafloor height h seabed The difference E is used to quantitatively calculate the existence status of the submarine cable and determine whether the submarine cable is exposed or suspended.

7. The submarine cable exposed pipe section detection system based on point cloud data according to claim 6 is characterized by: The slicing module further comprises: The contour point cloud set generating unit, given the point cloud data and a set of slice planes, generates two symmetrical auxiliary planes for each slice plane, and uses the points between the two auxiliary planes as the contour point cloud set corresponding to the slice plane; A point set determination unit, which traverses each point in the point cloud data according to the normal vector and plane equation of the slice plane, and determines the point set located on the slice plane; The projection processing unit projects the point set on the slice plane into the slice plane to obtain the section data point set corresponding to the slice plane.

8. The system for detecting exposed submarine cable sections based on point cloud data according to claim 7, characterized in that: The point set determination unit traverses each point in the point cloud according to the normal vector and plane equation of the slice plane. If a specific condition is met, it means that the point is on the slice plane, thereby obtaining the point set on the slice plane; the projection processing unit uses the vertical projection relationship to calculate the profile data point set corresponding to the slice plane through a specific formula.

9. The system for detecting exposed submarine cable sections based on point cloud data according to claim 6, characterized in that: The fitting module further comprises: The ellipse fitting unit assumes that the cross section of the submarine cable is approximately an ellipse, uses the general form of the ellipse equation to fit, solves the geometric parameters of the ellipse, and calculates the height of the submarine cable; The polynomial fitting unit performs polynomial fitting on the seabed topography point cloud profile data, and selects the highest point of the fitting segment from the fitted polynomial as the seabed height for the subsequent calculation of the submarine cable existence status.

10. The submarine cable exposed pipe section detection system based on point cloud data according to claim 6, characterized in that: It also includes an output module for outputting visual detection results to display the specific location and relevant parameters of the exposed pipe section of the submarine cable.

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