Anchor position detection method based on traversal algorithm and data set optimization algorithm and its application

Abstract

The present invention provides an anchor detection method based on a traversal algorithm and a data set optimization algorithm, and its application. Using an anchored vessel anchoring area detection model, the method sequentially calculates a set of anchorage obstacle coordinates and a set of anchor point coordinates generated using a Monte Carlo random algorithm to simulate the anchoring site of a vessel to be moored. This method obtains a two-dimensional coordinate set of the anchoring site that meets the ship safety spacing value. A traversal operation is then performed on the points within the anchor circle using a data set optimization algorithm. The traversal results are then compared with the draft and depth values ​​of the vessel to be moored, thereby obtaining an anchor point that meets both two-dimensional and three-dimensional water depth requirements. This method can achieve three-dimensional detection of the ship's anchor position by limiting the water depth while meeting the two-dimensional safety spacing limit. This method provides the operator with anchor point data that meets the water depth limit while meeting the planar safety spacing limit, significantly improving the accuracy and safety of ship anchor detection and selection during actual mooring operations.

Description

[0001] This application is a divisional application of the Chinese invention patent with application date of "2024.07.03", application number "202410883588.3", and invention name "3D anchor detection method based on traversal algorithm and data set optimization algorithm". Technical Field

[0002] The present invention relates to the technical field of ship anchoring, and in particular to an anchor position detection method based on a traversal algorithm and a data set optimization algorithm and an application thereof. Background Art

[0003] Currently, the development of various types of intelligent ship technologies is booming, gradually becoming a driving force for economic development in the shipping industry and a breakthrough in digital shipping technology. Intelligent anchor detection is a key technology essential for intelligent navigation. In recent years, the Chinese government has placed significant attention and support on the development of various types of intelligent ship technologies, prioritizing the promotion of marine engineering equipment and high-tech ships as key areas of development. Therefore, intelligent ships have become a trend in the development of maritime transportation and a key breakthrough point. my country is also actively developing research into core technologies for intelligent ships. In practice, ships must possess anchor detection capabilities at ports of origin, destination, and near routes to meet emergency response needs, cargo loading and unloading, crew embarkation and disembarkation, and berthing requirements. However, due to the lack of scientific anchor detection methods, operators typically rely on external information such as surface obstacles and ship distribution, as well as their own experience, to select anchorages. However, in practice, larger anchoring radiuses are often selected to ensure safe anchoring, resulting in a waste of anchorage resources. Conversely, if a ship chooses an anchoring radius that is too small, it can pose a safety hazard. Therefore, whether a ship can rationally plan and select anchoring locations and maintain safety during anchoring operations is a major challenge facing intelligent ship detection technology. Therefore, an intelligent anchoring detection technology that balances high efficiency and good safety performance is a key technology that urgently needs to be researched in the field of intelligent ships.

[0004] Zhang Chunyu used a ship anchoring safety distance model that takes wind factors into account to calculate the anchoring safety distances for three types of ships, optimized the navigation mode of single-anchored ships, and improved the safety of ship anchoring. At the same time, combined with the anchoring statistical data of Tianjin Port, he carried out safety planning for the anchorage waters and solved the problem of uneven utilization of anchorage resources.

[0005] Xie Si et al. proposed an improved ship anchor circle radius model, used the Monte-Carlo random algorithm to simulate the target ship to be moored, and used the improved ship anchor circle radius model to realize the ship anchor position detection in two-dimensional space on the water surface, solving the problem of two-dimensional plane anchor position detection.

[0006] Zhang Hongchi proposed a method for selecting single anchoring positions for unmanned ships based on a decision tree algorithm. He combined the decision tree algorithm with raster processing technology and preliminarily applied water depth information and bottom analysis to the intelligent anchoring position selection of unmanned ships.

[0007] Madadi, Bahman, et al. considered how to dynamically program the placement of ships arriving and departing from an anchorage within a polygonal anchorage. This study specifically considered the objectives of anchorage area utilization, ship collision risk, and fuel consumption performance. These three objectives defined the objective function as a weighted sum, and a spatiotemporal approach to this multi-objective anchorage planning problem was proposed. Monte Carlo simulation was used to measure the impact of any specific combination of planning metrics (measured in real time for incoming ships) on the objective function (measured in steady state). The perturbed stochastic approximation (SPSA) algorithm was also employed to determine the linear combination of planning metrics that optimizes the objective function.

[0008] Malekipirbazari et al. optimized the algorithm when studying the anchorage allocation problem and introduced a heuristic algorithm to correct the MHDF algorithm, taking into account the unevenness of the anchorage water depth. The algorithm is called the non-uniform maximum voidness first algorithm (NU-MHDF), and experimental comparisons have verified that its effect is better than the MHDF algorithm.

[0009] Huang believes that the availability of an anchorage depends on the actual anchoring locations chosen by ships. This study modeled the anchorage allocation problem using a disk-filling algorithm and proposed a maximum hole-first (MHDF) algorithm to solve it. An anchor simulation tool was designed to evaluate the algorithm's performance, which was also used in Singapore's ship traffic simulation system.

[0010] Oz et al. first considered anchor safety in the anchorage allocation problem. To maximize anchorage utilization and minimize accident risks, they proposed a multi-objective optimization anchorage allocation strategy. This study employed a Monte Carlo simulation algorithm to establish a simulation system for solution and verification.

[0011] In summary, despite some progress in intelligent anchor detection technology, continued innovation and improvement are still needed. Existing technologies typically rely on traditional two-dimensional observation methods, ignoring the impact of water depth on anchoring safety. This makes it difficult for crew members and shore-based management to effectively assess the selected anchoring waters. Consequently, actual anchoring operations can result in low anchoring accuracy and significant safety risks.

[0012] The above-mentioned record of background technology knowledge is intended to help ordinary technicians in this field understand the existing technology that is relatively close to the present invention, and at the same time facilitate the understanding of the inventive concept and technical solution of the present invention. It should be clear that in the absence of clear evidence that the above-mentioned content has been disclosed before the filing date of this patent application, the above-mentioned background technology should not be used to evaluate the novelty of the technical solution of this application. Summary of the Invention

[0013] Technical issues

[0014] In order to solve the above problems, it was found in the process of detecting 3D anchor positions by combining the Monte Carlo algorithm with the traversal algorithm that there are a large number of repeated operations in the water depth anchor position detection process, which need to be optimized. Therefore, the purpose of the present invention is to provide a 3D anchor position intelligent detection method that combines a Monte-Carlo random plane anchor position detection algorithm, a traversal algorithm and a data set optimization algorithm, which optimizes the large number of repeated operations in the traversal algorithm, can reduce the amount of calculation in the water depth detection part of the anchor position detection process by about 60%, and significantly improve the detection efficiency.

[0015] Technical Solution

[0016] In order to achieve the above-mentioned objectives, the inventors of the present application have conducted in-depth research and provided a three-dimensional anchor position intelligent detection method that combines the Monte-Carlo random plane anchor position detection algorithm, the traversal algorithm and the data set optimization algorithm. The method takes into account the water depth information in the anchor detection and can realize three-dimensional detection of the ship anchor position through the water depth restriction on the basis of satisfying the two-dimensional safety spacing restriction. Compared with the existing technology, both the observation accuracy and the anchor position selection safety are significantly improved, and the application of the data set optimization algorithm further improves the computing efficiency.

[0017] That is, the present invention is:

[0018] The 3D anchor detection method based on the traversal algorithm and the dataset optimization algorithm includes:

[0019] Using the anchoring area detection model of anchored ships shown in formula (6), the two-dimensional coordinate set S of the anchorage obstacles is b and the coordinate set S randomly generated by the Monte Carlo random algorithm to simulate the anchoring location m Perform successive calculations to obtain the two-dimensional coordinate set of the anchoring position that meets the safety distance value of the ship ;

[0020] (6)

[0021] In formula (6), Indicates the actual distance between ships; express The minimum value of ( Indicates the position of existing ships or other objects that hinder anchoring operations in the anchorage in the plane rectangular coordinate system; point ( Is the value of the safe distance between anchored ships Anchor site;

[0022] by The anchor point in the circle is the center and the anchor radius is the radius to draw the anchor circle. Within the anchor circle, the origin is Solstice Perform traversal operations in sequence, combine traversal operations with data set optimization algorithms, start from the starting point, and after the first traversal, add a data dimension to the water depth verification result of the point to indicate whether the water depth meets the requirements. Indicates that the safety water depth limit is met. It means that the safety depth limit cannot be met. Represents the traversal point, and includes the data that meets the water depth verification operation into the set ; In the second traversal, the traversal point coordinates and Compare the data points in the set. If there is such a data point, directly obtain the water depth verification data. Points without data will have their data values ​​added to the set after depth verification. By traversing the path from top to bottom and left to right at regular step intervals, the traversal results are compared with the draft and water depth of the vessel to be moored, resulting in an anchorage location that meets both 2D and 3D depth requirements. The process of detecting anchorage depth using a traversal algorithm inevitably involves a large amount of repeated operations, which require optimization. Therefore, a water depth detection method combining a traversal algorithm with a dataset optimization algorithm is proposed. This optimizes the numerous repeated operations in the traversal algorithm, reducing the amount of computation required for water depth detection by at least 60%, significantly improving detection efficiency.

[0023] Furthermore, if all points traversed within the anchor circle of the anchor point meet the water depth requirement, then the anchor point is an anchor point for a ship to be moored that meets the two-dimensional plane and three-dimensional water depth requirements.

[0024] Furthermore, if during the traversal process, the water depth verification result finds that any point in the anchor circle at the anchor point does not meet the water depth restriction condition, the water depth detection within the anchor circle is skipped, and the anchor point does not meet the requirements of the anchor point for the ship to be berthed that meets the two-dimensional plane and three-dimensional water depth requirements, and the point is eliminated.

[0025] Furthermore, the step interval is selected from any value between 0.1m and 10m.

[0026] Furthermore, the draft depth value of the ship to be moored is obtained by the draft detection model of the ship to be moored shown in formula (7):

[0027] (7)

[0028] In formula (7), Indicates the safe anchoring depth required for the ship to be moored; Indicates the ship's draft when at anchor; represents the reference coefficient; Indicates the excess depth of waves; Indicates the simulated draft of the ship to be moored.

[0029] Furthermore, the 3D anchor detection method based on the traversal algorithm and the data set optimization algorithm specifically includes:

[0030] Step 1: Obtain the three-dimensional coordinates of each point on the bottom of the anchorage , whose coordinate set is recorded as ; and It represents the coordinates of a two-dimensional rectangular coordinate system, and can also represent the points on the water surface of the anchorage. Indicates points on the water surface the depth of water;

[0031] Step 2: Obtain the 2D coordinates of the anchorage obstacle , whose coordinate set is recorded as ;

[0032] Step 3: Construct the anchorage point conversion model shown in formula (3) to convert the two-dimensional coordinates of the anchorage obstacle in step 2 into the anchorage point of the existing anchored ship. , whose coordinate set is recorded as ;

[0033] (3)

[0034] In formula (3), Indicates the distance between the anchoring point of the existing anchored ship and the point actually recorded by the ship. ≈Ship length + Ship anchor chain length; Indicates the angle between the bow direction and the abscissa in the coordinate system;

[0035] Step 4: Set the safety radius R with the two-dimensional coordinates of the anchorage obstacle in step 2 as the center of the circle. d The restricted waters, whose coordinate set is S d ; and construct the safety distance model shown in formula (4);

[0036] (4)

[0037] In formula (4), Indicates the safe distance value between ships; and The captains of the existing anchored vessels and the vessels waiting to be anchored are respectively; and Respectively represent the anchor chain length of the existing anchored ship and the ship to be anchored (m); and The radius of the anchorage circle of the existing anchored ship and the ship to be anchored (m); The ship type coefficients of the existing anchored ship and the ship to be anchored respectively;

[0038] Step 5: Import the relevant information such as the length of the existing anchored ship and the length of the anchored chain into the safety distance model shown in formula (4) to calculate the anchor circle radius of the existing anchored ship and the safety distance value of the ship to be anchored ;

[0039] Step 6: Generate random numbers using the Monte Carlo random algorithm Two-dimensional coordinates , whose coordinate set is denoted as S m , used to simulate the selection of anchoring sites for ships to be moored;

[0040] Step 7: Construct the anchoring area detection model of the anchored ship shown in formula (6):

[0041] (6)

[0042] In formula (6), Indicates the actual distance between ships; express The minimum value of ( Indicates the position of existing ships or other objects that hinder anchoring operations in the anchorage in the plane rectangular coordinate system; point ( Is the value of the safe distance between anchored ships Anchor site;

[0043] Step 8: Using the anchoring area detection model of anchored ships shown in formula (6), the coordinate set S b and S m Perform calculations one by one to obtain the two-dimensional coordinates of the anchoring point that meets the ship safety distance value in step 7 , whose coordinate set is ;

[0044] Step 9: Construct the draft detection model of the ship to be moored as shown in formula (7):

[0045] (7)

[0046] In formula (7), Indicates the safe anchoring depth required for the ship to be moored; Indicates the ship's draft when at anchor; represents the reference coefficient; Indicates the excess depth of waves; Indicates the simulated draft of the ship to be moored;

[0047] Step 10: The anchor point in the circle is the center and the anchor radius is the radius to draw the anchor circle. Within the anchor circle, the origin is Solstice Perform traversal operations in sequence, combine traversal operations with data set optimization algorithms, start from the starting point, and after the first traversal, add a data dimension to the water depth verification result of the point to indicate whether the water depth meets the requirements. Indicates that the safety water depth limit is met. It means that the safety depth limit cannot be met. Represents the traversal point, and includes the data that meets the water depth verification operation into the set ; In the second traversal, the traversal point coordinates and Compare the data points in the set. If there is such a data point, directly obtain the water depth verification data. Points without data will have their data values ​​added to the set after depth verification. By traversing the path from top to bottom and from left to right at a certain step interval, the traversal result is checked with the draft and water depth of the ship to be moored, and the anchoring point of the ship to be moored that meets the requirements of the two-dimensional plane and three-dimensional water depth is obtained. The point set is recorded as , judge by The coordinate points inside the anchor circle drawn by the center of the circle will not be in the point set The set of points inside is denoted as , whose coordinates are marked as ( ;

[0048] Step 11: Construct the anchor point conversion model shown in formula (9):

[0049] (9)

[0050] In formula (9), Indicates the distance between the anchor point of the ship to be anchored and the point actually recorded by the ship. ≈1.5×(ship length + ship anchor chain length); It is approximately expressed as the angle between the wind flow resultant force and the horizontal coordinate in the coordinate system; It is the set in step 10 Anchor point within The anchor points that meet the safety distance and water depth limit are obtained through calculation. The point set is recorded as .

[0051] Furthermore, in step 1, the third dimension data in the three-dimensional coordinates of the anchorage is the water depth of the location composed of the first two dimensions data.

[0052] Furthermore, in step 2, the anchorage obstacles include obstacles that cannot be moored and existing anchored ships.

[0053] Furthermore, in step 4, R d Set to 0.5 NM, 1 NM, or 2 NM.

[0054] Furthermore, in step 4, When the ship is an ordinary cargo ship, the lower limit is taken; when the ship is an oil, liquefied gas or chemical tanker, the upper limit is taken.

[0055] Furthermore, in step 9, the reference coefficient Take 1.2 when there is no surge or good shielding, and take 1.5 when there is surge or poor shielding.

[0056] The aforementioned 3D anchor position detection method based on the traversal algorithm and the data set optimization algorithm is applied in assisting ship anchoring operations.

[0057] Furthermore, the application includes sending a set of anchoring points that meet the safety spacing and water depth restrictions obtained according to the 3D anchor position detection method based on the traversal algorithm and the data set optimization algorithm to the ship to be moored to assist in anchoring.

[0058] A computer device comprising a memory, a processor, a communication interface, and a communication bus; wherein the memory, processor, and communication interface communicate with each other via the communication bus; the memory is used to store computer programs; the processor is used to execute the computer programs stored in the memory, and when the processor executes the computer program, it implements at least one step of the aforementioned 3D anchor detection method based on the traversal algorithm and the data set optimization algorithm.

[0059] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements at least one step of the above-mentioned 3D anchor detection method based on the traversal algorithm and the data set optimization algorithm.

[0060] On the basis of conforming to the common sense in this field, the above-mentioned preferred conditions can be combined with each other to obtain a specific implementation method.

[0061] Beneficial effects

[0062] According to the present invention, by combining the Monte-Carlo random plane anchor position detection algorithm with the traversal algorithm, three-dimensional detection of the ship anchor position can be achieved through water depth restriction on the basis of satisfying the two-dimensional safety distance restriction. The three-dimensional anchoring intelligent detection technology considering the water depth conditions proposed in the present invention will undoubtedly make the actual anchoring operation safer, and provide the driver with a method of satisfying the water depth limit while satisfying the plane safety distance.

[0063] Combining the dataset optimization algorithm during traversal can greatly improve computational efficiency, thereby optimizing a large number of repetitive operations in the 3D anchor detection algorithm. It can reduce the amount of computation in the water depth detection part of the anchor detection process by at least 60%, significantly improving the efficiency of the 3D anchor detection algorithm and helping ships to anchor promptly and quickly.

[0064] The generated anchorage data greatly improves the accuracy and safety of anchorage detection and selection during actual anchoring operations. This method takes into account the draft parameters of different ship types under different loading conditions. This method can provide operators with more accurate and applicable reference data during actual anchoring operations, allowing ship operators to select safe and controllable anchorages as needed during normal operation or emergency situations. In practical applications, the algorithm can be deployed on ship-related equipment, and the detected three-dimensional anchorage area can be intuitively displayed on the ECDIS system or other information systems, allowing ship operators to select safe and controllable three-dimensional anchorages during normal operation or emergency situations.

[0065] The present invention adopts the above technical solution to achieve the above purpose, which makes up for the shortcomings of the existing technology and has reasonable design and convenient operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to make the above-mentioned and / or other purposes, features, advantages and examples of the present invention more obvious and easy to understand, the following is a brief introduction to the drawings required for use in the specific embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0067] Figure 1 A technical roadmap of the 3D anchor detection method of the present invention is shown;

[0068] Figure 2 It shows the simulation diagram of No.1 anchorage;

[0069] Figure 3 It shows the simulation diagram of anchorage No.2;

[0070] Figure 4 Schematic diagram of randomly generated anchor points in the MATLAB platform;

[0071] Figure 5 A schematic diagram showing the anchoring locations that meet the safety spacing values;

[0072] Figure 6 A schematic diagram showing the path of the traversal algorithm operation;

[0073] Figure 7 Schematic diagram showing the simulation results of the anchoring point for a general cargo ship that meets the conditions at anchorage No. 1;

[0074] Figure 8 Schematic diagram showing the simulation results of the anchoring point where the tanker meets the conditions at anchorage No. 1;

[0075] Figure 9 Schematic diagram showing the simulation results of the chemical tanker's anchoring point meeting the conditions at anchorage No. 1;

[0076] Figure 10 Schematic diagram showing the simulation results of the container ship's anchoring point meeting the conditions at anchorage No. 1;

[0077] Figure 11 Schematic diagram showing the simulation results of the anchoring point for a general cargo ship that meets the conditions at anchorage No. 2;

[0078] Figure 12 Schematic diagram showing the simulation results of the anchoring point where the oil tanker meets the conditions at anchorage No. 2;

[0079] Figure 13 Schematic diagram showing the simulation results of the chemical tanker's anchoring point meeting the conditions at anchorage No. 2;

[0080] Figure 14 Schematic diagram showing the simulation results of the container ship's anchoring point that meets the conditions at anchorage No. 2.

[0081] Description of reference numerals: Figure 5 In the figure, pink represents the anchor points that meet the two-dimensional safety spacing; Figures 7 to 14 In the figure, purple points represent anchoring points that meet the two-dimensional conditions and the water depth limit in the ballast state. Yellow points represent anchoring points that meet the water depth limit in the fully loaded state based on the purple points. Green points are anchoring points that meet the requirements of the water depth generated within the anchoring circle based on the yellow points. It can be seen that there is no anchoring point that meets the water depth conditions in the 0-19.99m anchorage for container ships. DETAILED DESCRIPTION

[0082] Those skilled in the art may refer to the contents herein and appropriately substitute and / or modify the process parameters to achieve the desired effect. However, it should be noted that all such substitutions and / or modifications are obvious to those skilled in the art and are considered to be included in the present invention. The products and preparation methods described herein have been described through preferred embodiments. It is obvious that those skilled in the art can modify or appropriately change and combine the products and preparation methods described herein to implement and apply the technology of the present invention without departing from the content, spirit, and scope of the present invention.

[0083] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The present invention utilizes the methods and materials described herein; however, other suitable methods and materials known in the art may also be used. The materials, methods, and examples described herein are illustrative only and are not intended to be limiting. All publications, patent applications, patents, provisional applications, database entries, and other references mentioned herein are incorporated herein by reference in their entirety. In the event of a conflict, the present specification, including definitions, will control.

[0084] Unless otherwise specified, the materials, methods, and examples described herein are illustrative only and not limiting. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described herein.

[0085] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. At the same time, the embodiments in this application and the features in the embodiments can be combined with each other unless there is a conflict.

[0086] The present invention is described in detail below

[0087] Example 1:

[0088] like Figure 1 The technical route shown in this embodiment provides a 3D anchor position detection method based on a traversal algorithm and a data set optimization algorithm. A three-dimensional anchorage sea area is constructed in the matlab simulation software for 3D anchor position detection, which specifically includes the following steps.

[0089] Step S1: Construct a three-dimensional anchorage area of ​​n nautical miles x n nautical miles in MATLAB simulation software. The plane matrix model is constructed as shown in Equation (1); the anchorage depth model is constructed as shown in Equation (2). This simulation experiment uses a 3 nautical mile x 3 nautical mile chart scale.

[0090] (1)

[0091] In formula (1), is the matrix data generated by the meshgrid function, where The points contained in correspond to the coordinate axes The coordinates of the axis are denoted as , The points contained in correspond to the coordinate axes The coordinates of the axis are denoted as ,exist In the range of step size Divide and generate the corresponding grid matrix.

[0092] (2)

[0093] In formula (2), and is the coordinate of the two-dimensional rectangular coordinate system, The coordinates of each bottom point in the anchorage are constructed by the coordinate points generated by the above-mentioned model (1) and the model (2): The third dimension is the water depth of the location composed of the first two dimensions, and the coordinates of each point on the bottom of the water surface in the anchorage constitute the coordinate set .

[0094] In this simulation experiment, the water depth is divided into two intervals: This algorithm is also applicable to water depths above 45 m, but deep-water anchoring does not require much anchor position detection methods, so no relevant simulation experiments were conducted.

[0095] Step S2: Based on step S1, set the following anchorage:

[0096] Construct the No.1 anchorage with a water depth of 0 to 19.99 m at 3 nautical miles x 3 nautical miles, such as Figure 2 shown.

[0097] Construct the No.2 anchorage with a water depth of 20 to 39.99 meters at 3 nautical miles x 3 nautical miles, such as Figure 3 shown.

[0098] Step S3: Mark the obstacle information and the two-dimensional coordinates of the existing anchored ship collected or obtained by the ship's AIS equipment or radar equipment as , whose coordinate set is .

[0099] Step S4: Construct the anchor point conversion model shown in formula (3) to convert the two-dimensional coordinates of the anchorage obstacle in step S3 into the anchor point of the existing anchored ship , whose coordinate set is recorded as ;

[0100] (3)

[0101] In formula (3), Indicates the distance between the anchoring point of the existing anchored ship and the point actually recorded by the ship. ≈Ship length + Ship anchor chain length; Indicates the angle between the bow direction and the horizontal coordinate in the coordinate system; The anchoring points of existing ships in the anchorage are calculated, and their coordinates are recorded as S c .point is the two-dimensional coordinate of the existing ship recorded in step S3.

[0102] Step S5: Set the safety radius R with the two-dimensional coordinates of the anchorage obstacle in step S4 as the center of the circle. d The restricted waters, whose coordinate set is S d According to the actual situation of risk, R d Set to 3 levels: 0.5 nautical miles, 1 nautical mile, and 2 nautical miles.

[0103] Step S6: construct the safety distance model shown in formula (4);

[0104] (4)

[0105] In formula (4), Indicates the safe distance value between ships; and The captains of the existing anchored vessels and the vessels waiting to be anchored are respectively; and Respectively represent the anchor chain length of the existing anchored ship and the ship to be anchored (m); and The radius of the anchorage circle of the existing anchored ship and the ship to be anchored (m); The ship type coefficients of the existing anchored ship and the ship to be anchored respectively; When the ship is an ordinary cargo ship, the lower limit is taken; when the ship is an oil, liquefied gas or chemical tanker, the upper limit is taken.

[0106] Step S7: Import the relevant information such as the length of the existing ship and the length of the anchor chain into the safety distance model shown in formula (4) to calculate the anchor circle radius of the existing anchored ship. The static information of the ship used in this simulation experiment is shown in Table 1.

[0107] Table 1 - Ship type parameters selected for simulation experiment (m)

[0108]

[0109] Based on the ship parameters in Table 1, a MATLAB program was used to perform anchorage area inspection tests. The existing and pending vessels in the anchorage all belonged to the four types mentioned above, and the spacing between existing vessels in the anchorage met the safety spacing requirements for anchored vessels. The water depths in the anchorages were 0–19.99 m and 20–39.99 m, respectively.

[0110] Step S8: Based on steps S6 and S7, the safe distance value of the ship to be moored is calculated according to the safe distance model. ,The experimental data contains two categories and a total of 4 groups, as shown in Tables 2 to 5.

[0111] Table 2 - Safety distance data for ships in water depth of 19.99m and wind force ≤ 7 (m)

[0112] Serial number Captain of Ship 1 Chain length Safety radius Captain of Ship 2 Chain length Safety radius Safety distance 1 135 150 285 185 150 335 687 2 135 150 285 346 150 496 781 3 135 150 285 160 150 310 657 4 185 150 335 346 150 496 898 5 346 150 496 160 150 310 868 6 185 150 335 160 150 310 774

[0113] Table 3 - Safety distance data for ships in water depth of 19.99m and wind force > 7 (m)

[0114]

[0115] Table 4 - Safety distance data for ships in water depth of 39.99m and wind force ≤ 7 (m)

[0116]

[0117] Table 5 - Safety distance data for ships in water depth of 39.99m and wind force > 7 (m)

[0118]

[0119] Step S9: Generate randomly using Monte Carlo random algorithm Two-dimensional coordinates , whose coordinate set is denoted as S m , used to simulate the selection of anchoring sites for ships to be moored. This simulation experiment randomly generates 5000 random points, as shown in the schematic diagram. Figure 4 shown.

[0120] Step S10: construct the anchoring area detection model of the anchored ship shown in formula (6):

[0121] (6)

[0122] In formula (6), Indicates the actual distance between ships; express The minimum value of ( Indicates the position of existing ships or other objects that hinder anchoring operations in the anchorage in the plane rectangular coordinate system; point ( Is the value of the safe distance between anchored ships anchor point.

[0123] Step S11: Using the anchoring area detection model of the anchored ship shown in equation (6) of step S10, the coordinate set S of step S3 is b and the coordinate set S of step S9 m Perform calculations one by one to obtain the two-dimensional coordinates of the anchoring position that meets the ship safety distance value D in step S8 , whose coordinate set is , its schematic diagram is as follows Figure 5 As shown, Figure 5 In the figure, pink represents the anchor points that meet the two-dimensional safety distance.

[0124] Step S12: Constructing the draft detection model of the ship to be moored shown in formula (7):

[0125] (7)

[0126] In formula (7), Indicates the safe anchoring depth required for the ship to be moored; Indicates the ship's draft when at anchor; Indicates the reference coefficient, which is 1.2 when there is no surge or good shielding, and 1.5 when there is surge or poor shielding; Indicates the excess depth of waves; The relevant parameters of the ship in the simulation experiment are shown in Table 6.

[0127] Table 6-Simulation experiment ship parameters (m)

[0128] Ship name Ship Type Theoretical fully loaded draft of the ship Theoretical ballast draft of the ship Shielding factor Wave excess depth Actual full load water depth Actual ballast water depth Ship 1 general cargo ship 8.5 4.3 1.5 1.7 14.5 8.2 Ship 2 tanker 12 6 1.5 2.4 20.4 11.4 Ship 3 Chemical tanker 9.8 4.9 1.5 2.0 16.7 9.4 Ship 4 container ship 14.5 7.3 1.5 2.9 24.7 13.9

[0129] To increase the safety of anchorage selection, the shielding factor The upper limit helps to fully consider the safety risks caused by adverse conditions such as poor shielding, ship pitching, and surge in subsequent simulation tests. The wave margin depth is based on the UK "Offshore Structures" and is 20% of the ship's maximum draft.

[0130] Step S13:

[0131] Step S1301: Set the initial state: Draw an anchor circle with the anchor point in the center as the circle center and the anchor radius as the radius;

[0132] Step S1302: Determine the loop condition: within the anchor circle, from the origin Solstice Perform traversal operations in sequence;

[0133] Step S1303: Simulation operation: Starting from the starting point, traverse the path from top to bottom and from left to right with a step length of 1m. Figure 6 As shown, the result of the traversal operation is checked with the model water depth value shown in formula (7). If all the points traversed within this anchor circle meet the water depth requirements, then the anchor point is the anchor point to be moored that meets the two-dimensional plane and three-dimensional water depth requirements. If, during the traversal process, any point in the water depth verification result is found to not meet the water depth restriction condition, the water depth detection within the anchor circle where the center of the anchor point is located is skipped. This point does not meet the requirements of the anchor point to be moored that meets the two-dimensional plane and three-dimensional water depth requirements, and the point is eliminated. Finally, after traversing all the center points of the two-dimensional plane anchor circle, the anchor point to be moored that meets the two-dimensional plane and three-dimensional water depth requirements is obtained.

[0134] Step S1304: Dataset optimization: Traversing all points will inevitably result in a large number of repeated operations and reduce efficiency. Therefore, the traversal operation is combined with the data set optimization algorithm. Specifically, after the first traversal, a new data dimension is added to the water depth verification result of the traversed point to indicate whether the water depth meets the requirements. Indicates that the safety water depth limit is met. It means that the safety depth limit cannot be met. Represents the traversal point, and includes the data that meets the water depth verification operation into the set . In the second traversal, the traversal point coordinates and Compare the data points in the set. If there is such a data point, directly obtain the water depth verification data. Points without data will have their data values ​​added to the set after depth verification. By traversing the path from top to bottom and from left to right at a certain step interval, the traversal result is checked with the draft and water depth of the ship to be moored, and the anchoring point of the ship to be moored that meets the requirements of the two-dimensional plane and three-dimensional water depth is obtained. The point set is recorded as The step size of this simulation experiment can be any value between 0.1 and 10m, that is, to ensure the accuracy, it can be reduced to 0.5m, 0.1m or even smaller, but the amount of calculation will be greater.

[0135] For step S1304, if you directly The anchor point in the circle is the center and the anchor radius is the radius of the anchor circle. Solstice Performing the traversal operations sequentially took 20.6 seconds. However, incorporating the dataset optimization algorithm during the traversal reduced the time to just 6.5 seconds. This demonstrates that incorporating the dataset optimization algorithm during the traversal significantly improves computational efficiency, thereby optimizing the numerous repetitive operations in the 3D anchor detection algorithm. This reduces the computational load in the depth detection portion of the anchor detection process by at least 60%, significantly improving the efficiency of the 3D anchor detection algorithm and helping ships to anchor promptly and quickly.

[0136] Step S14: Determine The coordinate points inside the anchor circle drawn by the center of the circle will not be in the point set The set of points inside is denoted as , whose coordinates are marked as ( .

[0137] Step S15: Construct the anchor point conversion model shown in formula (9):

[0138] (9)

[0139] In formula (9), Indicates the distance between the anchor point of the ship to be anchored and the point actually recorded by the ship. ≈1.5×(ship length + ship anchor chain length); It is approximately expressed as the angle between the wind flow resultant force and the horizontal coordinate in the coordinate system; is the set in step S14 Anchor point within The anchor points that meet the safety distance and water depth limit are obtained through calculation. The point set is recorded as .

[0140] Step S16: Draw the anchor points of each reference ship that meet the safety distance and water depth limit through simulation. Figures 7 to 14 As shown, Figures 7-10 The simulation results of anchoring points that meet the conditions for general cargo ships, oil tankers, chemical tankers and container ships at the No.1 anchorage are shown. Figures 11-14 The simulation results of anchoring points that meet the conditions for general cargo ships, oil tankers, chemical tankers and container ships at the No.2 anchorage are shown. Figures 7 to 14 In the figure, the purple points represent the anchoring points that meet the two-dimensional conditions and the water depth limit in the ballast state. The yellow points represent the anchoring points that meet the water depth limit in the fully loaded state based on the purple points. The green points are the anchoring points that meet the requirements of being generated within the anchor circle and having a water depth that meets the requirements based on the yellow points. Figures 7 to 14It can be seen that the method of the present invention combines the Monte-Carlo random plane anchor detection algorithm, the traversal algorithm and the data set optimization algorithm to achieve more efficient three-dimensional detection of the ship anchor position by limiting the water depth on the basis of meeting the two-dimensional safety spacing limit. The three-dimensional anchoring intelligent detection technology considering the water depth condition will undoubtedly make the actual anchoring operation safer. In practical application, the algorithm can be arranged on ship-related equipment to assist the ship in anchoring. Figure 10 It can be seen that there is no anchorage point that meets the water depth requirements for container ships in the 0-19.99m anchorage.

[0141] Step S17: Send the result of step S16 to the electronic nautical chart or other relevant equipment to facilitate the ship to be moored to perform anchoring operations at this location; the ship to be moored selects a suitable anchoring point or ship position for anchoring operations according to actual needs.

[0142] Example 2:

[0143] A computer-readable storage medium is also provided, which stores a computer program that can be executed by a processor. When the computer program is executed by the processor, it runs at least one step of the aforementioned 3D anchor detection method based on the traversal algorithm and the data set optimization algorithm, and can achieve the same technical effect. To avoid repetition, this embodiment will not be described in detail.

[0144] Example 3:

[0145] A computer device, comprising a memory, a processor, a communication interface, and a communication bus; wherein the memory, processor, and communication interface communicate with each other via the communication bus; the memory is used to store computer programs; the processor is used to execute the computer programs stored in the memory, and when the processor executes the computer program, it implements at least one step of the aforementioned 3D anchor detection method based on the traversal algorithm and the data set optimization algorithm, and can achieve the same technical effect. To avoid repetition, this embodiment will not be described in detail.

[0146] Computer-readable media include permanent and non-permanent, removable and non-removable media, and can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0147] The conventional techniques in the above embodiments are prior arts known to those skilled in the art, and thus will not be described in detail here.

[0148] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope defined by the appended claims.

[0149] Although the present invention has been described in detail and certain specific embodiments have been cited, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

[0150] Although the above-mentioned specific embodiments have shown, described and pointed out the novel features applied to various embodiments, it should be understood that various omissions, replacements and changes can be made to the form and details of the described devices or methods without departing from the spirit of the present disclosure. In addition, the various features and methods described above can be used independently of each other, or can be combined in various ways. All possible combinations and sub-combinations are intended to fall within the scope of the present disclosure. Many of the above-mentioned embodiments include similar components, and therefore, these similar components are interchangeable in different embodiments. Although the present invention has been disclosed in the context of certain embodiments and examples, it should be understood by those skilled in the art that the present invention can extend beyond the specifically disclosed embodiments to other alternative embodiments and / or applications and their obvious modifications and equivalents. Therefore, the present invention is not intended to be limited by the specific disclosure of the preferred embodiments herein.

[0151] Matters not covered in the present invention are all known technologies.

Claims

1. A 3D anchor detection method based on a traversal algorithm and a dataset optimization algorithm, characterized by: Specifically include: Step 1: Obtain the three-dimensional coordinates of each point on the bottom of the anchorage , whose coordinate set is recorded as ; and Represents the coordinates of each point on the anchorage water surface in a two-dimensional rectangular coordinate system. Indicates points on the water surface the depth of water; Step 2: Obtain the 2D coordinates of the anchorage obstacle , whose coordinate set is recorded as ; Step 3: Construct the anchorage point conversion model shown in formula (3) to convert the two-dimensional coordinates of the anchorage obstacle in step 2 into the anchorage point of the existing anchored ship. , whose coordinate set is recorded as ; (3) In formula (3), Indicates the distance between the anchoring point of the existing anchored ship and the point actually recorded by the ship. ≈Ship length + Ship anchor chain length; Indicates the angle between the bow direction and the abscissa in the coordinate system; Step 4: Set the safety radius R with the two-dimensional coordinates of the anchorage obstacle in step 2 as the center of the circle. d The restricted waters, whose coordinate set is S d ; and construct the safety distance model shown in formula (4); (4) In formula (4), Indicates the safe distance value between ships; and The captains of the existing anchored vessels and the vessels waiting to be anchored are respectively; and Respectively represent the anchor chain lengths of the existing anchored ship and the ship to be anchored; and The radius of the anchorage circle for existing anchored ships and ships waiting to be anchored; The ship type coefficients of the existing anchored ship and the ship to be anchored respectively; Step 5: Import the relevant information of the length of the existing anchored ship and the anchor chain length into the safety distance model shown in formula (4) to calculate the anchor circle radius of the existing anchored ship and the safety distance value of the ship to be anchored ; Step 6: Generate random numbers using the Monte Carlo random algorithm Two-dimensional coordinates , whose coordinate set is denoted as S m , used to simulate the selection of anchoring sites for ships to be moored; Step 7: Construct the anchoring area detection model of the anchored ship shown in formula (6): (6) In formula (6), Indicates the actual distance between ships; express The minimum value of ( Indicates the position of existing ships or other objects that hinder anchoring operations in the anchorage in the plane rectangular coordinate system; point ( Is the value of the safe distance between anchored ships Anchor site; Step 8: Using the anchoring area detection model of anchored ships shown in formula (6), the coordinate set S b and S m Perform calculations one by one to obtain the two-dimensional coordinates of the anchoring point that meets the ship safety distance value in step 5. , whose coordinate set is S e ; Step 9: Construct the draft detection model of the ship to be moored as shown in formula (7): (7) In formula (7), Indicates the safe anchoring depth required for the ship to be moored; Indicates the ship's draft when at anchor; represents the reference coefficient; Indicates the excess depth of waves; Indicates the simulated draft of the ship to be moored; Step 10: The anchor point in the circle is the center and the anchor radius is the radius to draw the anchor circle. Within the anchor circle, the origin is Solstice Perform traversal operations in sequence, combine traversal operations with data set optimization algorithms, start from the starting point, and after the first traversal, add a data dimension to the water depth verification result of the traversal point to indicate whether the water depth meets the requirements. Indicates that the safety water depth limit is met. It means that the safety depth limit cannot be met. Represents the traversal point, and includes the data that meets the water depth verification operation into the set ; In the second traversal, the traversal point coordinates and Compare the data points in the set. If there is such a data point, directly obtain the water depth verification data. Points without data will have their data values ​​added to the set after depth verification. In the middle, the path is traversed from top to bottom and from left to right with a step interval of any value between 0.1m and 10m. The traversal result is checked with the draft and water depth of the ship to be moored, and the anchoring point of the ship to be moored that meets the requirements of the two-dimensional plane and three-dimensional water depth is obtained. The point set is recorded as ,judge The points in the anchor circle with the coordinate point inside as the center will not be in the point set The set of points inside is denoted as , and mark the coordinates as ( ; Step 11: Construct the anchor point conversion model shown in formula (9): (9) In formula (9), Indicates the distance between the anchor point of the ship to be anchored and the point actually recorded by the ship. ≈1.5×(ship length + ship anchor chain length); It is approximately expressed as the angle between the wind flow resultant force and the horizontal coordinate in the coordinate system; It is the set in step 10 Anchor point within The anchor points that meet the safety distance and water depth limit are obtained through calculation. The point set is recorded as .

2. The method according to claim 1, wherein: If all points traversed within the anchor circle of the anchor point meet the water depth requirements, then the anchor point is an anchor point for a ship to be moored that meets the two-dimensional plane and three-dimensional water depth requirements; If, during the traversal process, the water depth check result shows that any point in the anchor circle of the anchor point does not meet the water depth restriction condition, the water depth detection within the anchor circle is skipped, the anchor point does not meet the requirements of the anchor point to be berthed that meets the two-dimensional plane and three-dimensional water depth requirements, and the anchor point is eliminated.

3. The method according to claim 1, wherein: In step 2, the anchorage obstacles include obstacles that cannot be moored and existing anchored ships.

4. The method according to claim 1, wherein: In step 4, R d Set to 0.5 NM, 1 NM, or 2 NM.

5. The method according to claim 1, wherein: In the step 4, When the ship is an ordinary cargo ship, the lower limit is taken; when the ship is an oil, liquefied gas or chemical tanker, the upper limit is taken.

6. The method according to claim 1, wherein: In step 9, the reference coefficient Take 1.2 when there is no surge or good shielding, and take 1.5 when there is surge or poor shielding.

7. Application of the 3D anchor position detection method based on the traversal algorithm and the data set optimization algorithm as described in any one of claims 1 to 6 in assisting ship anchoring operations.

8. The use according to claim 7, characterized in that: The application includes sending a set of anchoring points that meet safety spacing and water depth restrictions obtained according to the 3D anchor position detection method based on the traversal algorithm and the data set optimization algorithm to the ship to be moored to assist in anchoring.

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