An efficient analysis method for flexible connectors between complex floating body modules

Abstract

The application discloses a kind of high-efficiency complex configuration flexible connector analysis method between floating body module, comprising the following steps: respectively obtaining the total load of rubber pad and cable, and sum processing is carried out, obtains connector total load;Obtain wave excitation force, based on the connector total load and wave excitation force constructs floating platform dynamics control equation;Based on the floating platform dynamics control equation, the hydrodynamic response of connector is obtained;Based on the hydrodynamic response of connector, the optimization of connector key parameter is carried out.The application efficiently extracts the equivalent linear stiffness matrix of flexible connector of multi-module floating platform under multi-parameter condition, and substitutes into the technical means of joint response solution carried out in multi-module floating platform dynamics equation, reaches the technical effect that both guarantee the mechanical simulation accuracy of flexible connector is in reliable range, and also gives consideration to calculation efficiency, to provide model support for the parameter optimization design of complex configuration flexible connector.

Description

Technical Field

[0001] This invention belongs to the field of flexible connector design technology between floating bodies of ultra-large offshore floating platforms, and in particular relates to an efficient analysis method for flexible connectors between modules of complex floating bodies. Background Technology

[0002] Very Large Floating Structures (VLFSs) differ from traditional hundred-meter-class ships and offshore platforms; they are giant marine engineering equipment with dimensions reaching thousands of meters. VLFSs can be widely used in many engineering fields such as floating sea and air ports, floating cities, floating hotels, and offshore military bases, and can be deployed in nearshore, offshore, or near islands and reefs. Due to the enormous size of VLFS structures, using a single continuous structure would result in a huge structural load, seriously affecting the platform's safety and making it difficult to manufacture and install. Therefore, VLFS should adopt a modular design, with modules connected by connectors.

[0003] Modularly assembled ultra-large offshore floating platforms form a multi-oscillator network system with rigid-flexible-fluid coupling. Flexible connectors arranged between modules play a crucial role in maintaining the stability and safety of the overall system. Parameters such as the structural stiffness and material elastic modulus of the flexible connectors significantly influence the motion response and connection load of the floating body system. Reasonable connector parameter design can effectively improve the overall system's response characteristics. While there is considerable research on the key parameters of flexible connectors, much of it focuses on point-contact connectors, simplifying them into multi-point spring connection models, which deviates significantly from real-world results and is ineffective for surface-contact flexible connectors. Some researchers have coupled a refined finite element mechanical model of surface-contact connectors with a floating platform dynamics model to conduct full-time-domain dynamic calculations and analyses. The results show that surface-contact connectors have significant advantages in alleviating stress levels and preventing local stress concentration. Furthermore, tank tests verified the reliability of the numerical analysis conclusions. However, the refined analysis model is time-consuming, which is not conducive to practical engineering applications. Summary of the Invention

[0004] The purpose of this invention is to provide an efficient analysis method for flexible connectors between complex floating body modules. This method analyzes the dynamic response characteristics of flexible connectors and uses Python-Abaqus secondary development to establish an efficient calculation model of the system hydrodynamic response under different connector structural stiffness and material elastic modulus conditions. This supports the multi-parameter optimization and selection design of flexible connectors, thereby solving the problems existing in the prior art.

[0005] To achieve the above objectives, this invention provides an efficient method for analyzing flexible connectors between modules of complex floating bodies, comprising the following steps:

[0006] The total loads of the rubber pad and the cable are obtained separately, and then summed to obtain the total load of the connector.

[0007] Obtain the wave excitation force, and construct the dynamic control equations of the floating platform based on the total load of the connector and the wave excitation force;

[0008] The hydrodynamic response of the connector is obtained based on the dynamic control equations of the floating platform.

[0009] The key parameters of the connector are optimized based on the hydrodynamic response of the connector.

[0010] Optionally, the expression for the dynamic control equation of the floating platform is:

[0011]

[0012] Among them, X i =[x i ,y i ,z i ,α i ,β i ,γ i ] T M represents the displacement response matrix of a floating body with six degrees of freedom. i S represents the quality matrix of module i. i Let A represent the still water restoring stiffness matrix. ij B ij and φ represents the hydrodynamic coefficients, additional mass, additional damping, and wave excitation force, respectively. ij G(X) represents an element of the connection topology matrix φ. i ,X j ) represents the mechanical model of the connector.

[0013] Optionally, the connector mechanical model G(X) i ,X j The expression for ) is:

[0014] G(X i ,X j )=G1(X i ,X j )+G2(X i ,X j )

[0015] Among them, G1(X) i ,X j ) and G2(X i ,X j ) represent the total loads exerted on the centroid of module i by the cable and rubber pad between module i and module j, respectively.

[0016] Optionally, the process of obtaining the total load of the cable acting on the centroid of module i includes: obtaining the cable force at a point on the connecting end face of module i based on the distance between the two ends of the cable, the initial length of the cable when it is not stretched, the tensile stiffness of the cable, and the unit direction vector of the cable; obtaining the lever arm vector from the point on the connecting end face of module i to the centroid of module i; obtaining the bending moment generated by the centroid of module i based on the lever arm vector and the cable force; and summing the cable force and bending moment of all cables between module i and module j to obtain the total load of the cable acting on the centroid of module i.

[0017] Optionally, the process of obtaining the distance between the two ends of the cable includes: based on the initial position of the module's centroid in the global coordinate system, the translational and rotational displacements of the module in the local coordinate system, the positions of the points on the module's connecting end faces in the ship's coordinate system, and the rotation-position transformation matrix, obtaining the new positions of the corresponding points on the connecting end faces of module i and module j in the global coordinate system, and subtracting the new positions of the corresponding points on the connecting end faces of module i and module j in the global coordinate system to obtain the distance between the two ends of the cable.

[0018] Optionally, the process of obtaining the total load of the rubber pad acting on the center of mass of module i includes: applying unit relative displacements to the two floating modules connected by the rubber pad in six degrees of freedom directions respectively, and extracting the support reaction forces acting on the center of mass of the two floating modules respectively, thereby obtaining the equivalent stiffness matrix of the rubber pad; based on the equivalent stiffness matrix and the coordinate transformation matrix from the global coordinate system to the local coordinate system of the connecting system, obtaining the total load of the rubber pad acting on the center of mass of module i.

[0019] Optionally, the process of obtaining wave excitation force includes: obtaining the wave incident angle and wave frequency, and obtaining the wave excitation force based on the wave incident angle and wave frequency using linear wave theory.

[0020] Optionally, the process of obtaining the hydrodynamic response of the connector includes: embedding the dynamic control equation of the floating platform into the feedback solution program of the finite element stress analysis to obtain the hydrodynamic response results. The hydrodynamic response results include at least the time series, the displacement response time series of each float, the relative displacement response time series of each float, the cable tension response time series, the relative displacement time series of the truncated float, the displacement response amplitude of each float, the tension response amplitude of each cable, the relative displacement response amplitude of each float, the short-term predicted value of the relative displacement of each adjacent float, the short-term predicted value of the displacement of each float, the short-term predicted value of the tension of each cable, and the short-term predicted value of the maximum tension of the cable.

[0021] The technical effects of this invention are as follows:

[0022] This invention utilizes the Python scripting language to control ABAQUS simulation calculations to efficiently extract the equivalent linear stiffness matrix of a flexible connector for a multi-module floating platform under multiple parameter conditions, and substitutes it into the dynamic equations of the multi-module floating platform to perform joint response solving. This achieves the technical effect of ensuring that the mechanical simulation accuracy of the flexible connector is within a reliable range while also taking into account computational efficiency, thereby providing model support for the parameter optimization design of flexible connectors with complex configurations. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0024] Figure 1 This is a schematic diagram of the analysis method for efficient flexible connectors between complex configuration floating body modules in an embodiment of the present invention;

[0025] Figure 2 This is a coordinate diagram of a multi-module connected floating platform in an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of a surface contact connector concept model in an embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the Python-Abaqus secondary development parameter optimization process in an embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of a hexagonal platform test case in an embodiment of the present invention;

[0029] Figure 6 The following are schematic diagrams of the hexagonal platform response under three wave heights in the embodiments of the present invention, wherein (a) is a schematic diagram of module sway, (b) is a schematic diagram of module transverse sway, (c) is a schematic diagram of module heave, (d) is a schematic diagram of single cable tension, and (e) is a schematic diagram of single rubber pad stress.

[0030] Figure 7 This is a schematic diagram of the maximum response characteristics of the hexagonal platform as a function of wave direction angle in an embodiment of the present invention, wherein (a) is a schematic diagram of the maximum load of the connector and (b) is a schematic diagram of the maximum displacement of the floating module. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0033] Example 1

[0034] This embodiment provides an efficient analysis method for flexible connectors between modules of a complex floating platform. The modularly assembled offshore floating platform connects the modules via flexible connectors. As a key component of a multi-module floating platform, the appropriate material selection and structural design of the flexible connector play a crucial role in the stability and safety of the overall system. The surface contact connector design utilizes rubber pads and cables, where the rubber pads can withstand tension, compression, bending, and shear, while the cables can only withstand tensile force.

[0035] This embodiment uses linear wave theory to derive the wave excitation force, and employs the Python-Abaqus secondary development tool to perform finite element simulation on the rubber pad, obtaining its equivalent stiffness. Combined with cable stiffness and the effect of floating body size, the connector load expression is derived. Finally, Newton's second law is used to establish the dynamic control equations for the surface contact connection multi-module floating platform, and the hydrodynamic response and connector load under different connector parameter conditions are calculated, thus providing a basis for the optimal selection of connector parameters. The specific establishment process is as follows... Figure 1 As shown.

[0036] The process of establishing the dynamic control equations for a floating platform:

[0037] Figure 2 This is a schematic diagram of the coordinates of a multi-module connected floating platform, where OXYZ is the global coordinate system, and the XOY plane is located at the free surface. i x i y i z i Let i be a local coordinate system, with the origin located at the centroid of the module, and x... i o i y i The plane is parallel to the XOY plane. ψ represents the wave incident angle.

[0038] According to network dynamics, the dynamic equations of a multi-floating body system composed of N modules connected by inter-module connectors can be expressed as:

[0039]

[0040] Among them, X i =[x i ,y i ,z i ,α i ,β i,γ i ] T M represents the array of six-degree-of-freedom displacement responses (sway, roll, heave, pitch, pitch, bow) of a floating body. i S represents the quality matrix of module i. i This represents the still water restoring stiffness matrix. A ij B ij and The hydrodynamic coefficients, including added mass, added damping, and wave excitation force, are obtained using linear wave theory. φ ij Let G(X) be an element of the connection topology matrix φ. A value of 0 indicates that modules i and j are not connected, while a value of 1 indicates that modules i and j are connected. i ,X j ) represents the mechanical model of the connector, and its expression is related to the connector configuration.

[0041] Construction of the mechanical model of a surface contact connector:

[0042] Surface contact connectors typically have the following configurations: Figure 3 As shown, the flexible pad is used to constrain the compression, bending, and shearing movements between modules, and the cable is used to constrain the separation movements between modules.

[0043] Currently, research has proposed the concept of rubber-steel cable surface contact connectors and applied them to the connection of linearly connected modular floating airports. To simplify calculations, the steel cable and rubber are considered as linear elastic elements with different stiffness coefficients, and a simplified model considering only the two degrees of freedom of the module's sway and heave is constructed to study related dynamic response characteristics. Other researchers, to further evaluate the superior mechanical performance of surface contact connectors, have established a refined mechanical model of the connector using the finite element method. In this model, the flexible pad is divided into several eight-node hexahedral elements, the cable is considered as a tension spring, and a full-time-domain dynamic model is constructed by coupling it with the rigid module's rigid body dynamics model. The load on the surface contact connector is obtained by dynamically updating the node coordinates connected to the floating body end face, which results in extremely slow calculation speed for subsequent overall system dynamic analysis. Furthermore, the rubber pad can only consider one layer of mesh elements, making it difficult to guarantee simulation accuracy. Clearly, for multi-directional layout surface contact connectors with a rapidly increasing number of connected floating bodies and complex connection methods, using a refined finite element mechanical model for time-domain calculations is almost impossible for solving large-scale cases, severely restricting its engineering design and performance evaluation capabilities.

[0044] This embodiment proposes a simplified mechanical modeling method for multi-directional surface contact connectors. By introducing the PYTHON-ABAQUS co-simulation method, the equivalent stiffness matrix of the flexible pad under different material parameter conditions is extracted and can be dynamically imported into the network dynamics model of a multi-module floating platform for efficient time-domain dynamic solution. Furthermore, the platform displacement response can be fed back in real time for dynamic stress and tension analysis of the flexible pad and cable. For the cable, considering that the tension in its stretched state is always along the cable axis, it is treated as a spring model that can only withstand axial tension, which has little impact on the accuracy of the response solution. Therefore, when modules i and j are connected through the surface contact connector, the connector mechanical model G(X) i ,X j This can be represented as:

[0045] G(X i ,X j )=G1(X i ,X j )+G2(X i ,X j (2)

[0046] Where G1(X) i ,X j ) and G2(X i ,X j ) represent the total loads exerted on the centroid of module i by the cable and rubber pad between modules i and j, respectively.

[0047] First, for a single cable, assuming its two ends are connected to point p on the connecting end face of module i and point q on the connecting end face of module j respectively, when module i is displaced, point p will move to a new position in the global coordinate system OXYZ:

[0048]

[0049] Where X i,0 =[X i,0 ,Y i,0 Z i,0 ] T This represents the initial position of the centroid of module i in the global coordinate system, X. i,1 =[x i ,y i ,z i ] T and X i,2 =[α i ,β i ,γ i ] T Representing module i in its local coordinate system o i x i y i zi Translational and rotational displacements. This indicates that point p is in the ship's coordinate system o of module i. mi x mi y mi z mi The position within the module. T(·) represents the angle-position transformation matrix, used to calculate the position change of local points on the module caused by the module's angle movement. Its expression is as follows:

[0050]

[0051] Similarly, the new position of point q on the connecting end face of module j in the global coordinate system can be obtained. Therefore, the distance between the two ends of the cable can be obtained by the following formula:

[0052]

[0053] Because the cable can only withstand tensile force, its stiffness exhibits piecewise nonlinear characteristics in the local coordinate system o. i x i y i z i In the diagram, the force exerted by the cable on point p on the connecting end face of module i can be expressed as:

[0054] f ij,p =max(0,k) c (L ij,pq -L0))n ij,pq (6)

[0055] Where L0 is the initial length of the cable when it is not stretched. k c This indicates the tensile stiffness of the cable. ij,pq The unit direction vector of the cable can be obtained by the following formula:

[0056]

[0057] Since the cable force acts directly on the connection end face of the module as a concentrated load, it will generate a bending moment at the center of mass of the module:

[0058] m ij,p =r i,p ×f ij,p (8)

[0059] Where r i,p The lever arm vector representing the distance from point p to the centroid of module i is expressed as:

[0060]

[0061] Assuming there are M cables arranged between modules i and j, the total load acting on the center of mass of module i can be obtained by summing them up:

[0062]

[0063] For rubber pads (flexible pads), it is difficult to characterize their surface contact characteristics using the previously simplified spring model. Furthermore, coupling the finite element simulation model with the floating body model for time-domain solutions leads to significant computational overhead, making it unsuitable for practical engineering applications. This embodiment establishes an equivalent mechanical model of the flexible pad based on the Python-Abaqus-Matlab co-simulation method and couples it into a complex configuration platform network dynamics model for efficient time-domain dynamic solutions.

[0064] Assuming minimal relative angular motion between the floating modules, unit relative displacements are applied sequentially to the two floating modules connected by the flexible pad in each of the six degrees of freedom. The support reactions acting at the center of mass of each module are then extracted, yielding the equivalent stiffness matrix of the flexible pad. Coupled with the equivalent stiffness extraction process of the flexible pad into the network dynamics analysis program, and embedding a feedback solver that calls ABAQUS finite element stress analysis, real-time evaluation of the floating module motion, cable tension, and rubber pad stress can be performed. It is worth noting that due to the angle θ between the local and global coordinate systems of the connection system around the Z-axis... ij Therefore, the mechanical model of the flexible pad between modules i and j can be expressed in the following form:

[0065]

[0066] Where T ij From the global coordinate system OXYZ to the local coordinate system o of the connecting system ij x ij y ij z ij The coordinate transformation matrix can be represented as:

[0067]

[0068] Where θ ij To connect the system's local coordinate system o ij x ij y ij z ij The rotation angle around the Z-axis relative to the global coordinate system OXYZ is positive when it is counterclockwise.

[0069] Programming:

[0070] Program for extracting the equivalent stiffness matrix of flexible pads:

[0071] Abaqus, a powerful and widely used finite element analysis software, can simulate various engineering environments and material properties, and solve structural stress and displacement problems. However, performing simulations within the Abaqus software interface typically requires manually adjusting various simulation parameters before submitting the calculation, consuming significant manual and computational time and hindering post-processing optimization and evaluation. Python, as the scripting language for Abaqus, allows for control over Abaqus finite element modeling and simulation calculations, and is supplemented by numerous third-party libraries, including efficient mathematical calculation libraries, data visualization libraries, and optimization analysis libraries. By editing Abaqus scripts (Python files), various simulation parameters of the structure can be directly controlled, reducing unnecessary repetitive calculations and efficiently extracting evaluation indicators such as stress and displacement from the Abaqus finite element calculation post-processing files. Furthermore, adding loops to the Python scripts allows for optimal structural parameter design. The Python-Abaqus secondary development parameter optimization process is as follows: Figure 4 As shown, assuming the key parameters of the flexible connector to be optimized include a, b, c, etc., firstly, the key parameters within the initial setting range are iterated in the Python scripting language according to a certain step size, and then imported into ABAQUS for continuous simulation calculation; then the equivalent linear stiffness matrix and the maximum stress and tension of the connector under the multi-parameter conditions obtained by the simulation calculation are saved to an Excel file; finally, the user can select the appropriate key parameter ratio according to the calculation results.

[0072] Considering that the equivalent stiffness matrix of the flexible pad needs to be obtained by applying unit displacements to adjacent modules in each of the six degrees of freedom and performing finite element analysis, and that extracting the equivalent stiffness matrix of the flexible pad from a large number of elastic modulus indices within a certain range is also necessary for optimal selection of the flexible pad's characteristic parameters, directly performing successive finite element simulations and data recording of the flexible pad within the Abaqus software interface is clearly impractical. Therefore, a program for extracting the equivalent stiffness matrix of the flexible pad needs to be designed using the Python language.

[0073] First, when running the Python program in the file directory "D:\Face-contact\Cushionanalysis" to extract the equivalent stiffness matrix of the flexible pad, you need to set the calculation interval and calculation step size of the elastic modulus of the flexible pad in the program. Then, it is recommended to run the Python program for extracting the equivalent stiffness matrix of the flexible pad in the following way: Open the Abaqus software, click File - Run Script, select the Python file in the folder of the equivalent stiffness extraction program for the flexible pad, and the calculation will start immediately.

[0074] After the calculation is complete, create a new file named KK.xlsx in the directory of the dynamic response calculation program files "D:\Face-contact". Copy the contents of the file Kmatrix.txt in the directory "D:\Face-contact\Cushionanalysis" to the KK.xlsx file for later use.

[0075] Multi-module floating surface contact connector dynamic response calculation program:

[0076] The dynamic analysis program was written in Matlab (program files directory "D:\Face-contact"). Solving the dynamic equations utilizes Matlab's built-in ode45 function; details can be found in the source code. Before running the program, relevant simulation parameters must be input in the main program "Solve_Response.m", primarily including the calculation range for the elastic modulus ee of the flexible pad and the calculation step size.

[0077] After the above feature parameters are input, the number of parameter loops can be determined according to the requirements.

[0078] Once the loop parameters are selected, the main program can be started. During the calculation, the Matlab command line window will display the calculation completion status and completion time under different loop sizes.

[0079] After the dynamic response calculation is completed, the short-term predicted values ​​of displacement response (ExtreRX), short-term predicted values ​​of relative displacement between adjacent floats (ExtreRdx), short-term predicted values ​​of tension in each cable (ExtreRopeForce), and the time series of relative displacement of the truncated float (dx1) will be generated. These are all saved in the result file “D:\Face-contact\Getcushionstress\E?-K?-Ang=?.mat”. The time series (t) corresponding to different wave frequencies, the time series of float displacement response (x), the time series of relative float displacement response (dx), and the time series of tension in each cable (RopeForce) are also saved in the result file “D:\Face-contact\E=?K=?-Ang=?-Fre=?.mat”, which users can view. Table 1 shows the variable table of the result file generated by the dynamic response calculation program.

[0080] Table 1

[0081] t Time series x Displacement response time series of each floating body dx Time series of relative displacement response of each floating body RopeForce Cable tension response time series dx1 Time series of relative displacement of the buoy after truncation ampXModule Displacement response amplitude of each floating body ampRopeForce Tension response amplitude of each cable ampdx Relative displacement response amplitude of each floating body ExtreRdx Short-term forecast values ​​of relative displacement between adjacent floating bodies ExtreRX Short-term forecast values ​​of displacement of each floating body ExtreRopeForce Short-term forecast values ​​of tension in each cable MaxExtreRopeForce Short-term forecast of maximum tension of cable

[0082] Note that, in order to reduce the time consumption of post-processing analysis of the flexible pad stress, the last cycle of the steady-state part will be extracted from the relative displacement time series of adjacent modules, and 20 sample points will be taken at equal intervals within this cycle. These samples will be fed back to Abaqus for finite element post-processing analysis to calculate the steady-state response of the maximum stress of the flexible pad.

[0083] Module floating body surface contact connector flexible pad stress feedback program:

[0084] After the above dynamic response calculations are completed, all results are automatically saved as files named "E?-K?-Ang=?.mat" in the flexible pad stress feedback program folder "D:\Face-contact\Getcushionstress". When running the Python program to calculate the steady-state stress response of the flexible pad of the multi-module floating surface contact connector, the input to the Python program needs to be modified accordingly based on the selected values ​​of elastic modulus, cable stiffness, and wave incident angle from the previous step.

[0085] Then, it is recommended to run the Python program for stress feedback of the flexible pad of the multi-module floating body surface contact connector as follows: Open the Abaqus software, click File - Run Script, select the Python file in the Multi-module Floating Body Surface Contact Connector Flexible Pad Stress Feedback Program folder, and the calculation will begin immediately.

[0086] After the program completes the calculation, the stress response time series of the flexible pad will be saved in the file directory "D:\Face-contact\Getcushionstress" as "stressE?.txt". You can directly copy it to an Excel file to plot and view it.

[0087] Hexagonal Platform Test Case:

[0088] like Figure 5 As shown, this embodiment applies a surface contact connector composed of cables and rubber pads to a hexagonal platform, and performs dynamic analysis on the multi-directional layout surface contact connector of the complex platform based on a high-efficiency performance analysis system for multi-module floating surface contact connectors. Some of the calculation results are shown below. Figure 6 and Figure 7 As shown in the figure. The results show that if the finite element model of the flexible connector is combined with the time-domain dynamic model of the floating platform to carry out real-time dynamic response calculation, the required computational resources and computation time will be unsustainable. At the same time, if the mesh of the connector finite element model is not fine enough, the calculation results will be very unreliable. This further demonstrates the superiority of the proposed method.

[0089] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A highly efficient method for analyzing flexible connectors between modules of complex floating bodies, characterized in that, Includes the following steps: The total loads of the rubber pad and the cable are obtained separately, and then summed to obtain the total load of the connector. Obtain the wave excitation force, and construct the dynamic control equations of the floating platform based on the total load of the connector and the wave excitation force; The hydrodynamic response of the connector is obtained based on the dynamic control equations of the floating platform. The key parameters of the connector are optimized based on the hydrodynamic response of the connector. The expression for the dynamic control equation of the floating platform is: ； in, This represents the displacement response matrix of a floating body with six degrees of freedom. Representation module The mass matrix, This represents the still water restoring stiffness matrix. and These represent the hydrodynamic coefficients, additional mass, additional damping, and wave excitation force, respectively. Represents the connection topology matrix One of the elements, Represents the mechanical model of the connector; The connector mechanical model The expression is: ； in, and Representing modules respectively Module The cables and rubber pads between the modules act as a support. Total load on the center of mass; Cables act on the module The process of obtaining the total load at the center of mass includes: based on the distance between the two ends of the cable, the initial length of the cable when unstretched, the tensile stiffness of the cable, and the unit direction vector of the cable, obtaining the module. Cable force at the connection point; acquisition module Point-to-module connection on the end face The lever arm vector of the center of mass, based on the lever arm vector and the cable force, yields the module. Bending moment generated by the center of mass; module and modules The cable forces and bending moments of all cables are summed to obtain the cable force acting on the module. Total load on the center of mass; The process of obtaining the distance between the two ends of the cable includes: based on the initial position of the module's centroid in the global coordinate system, the translational and rotational displacements of the module in the local coordinate system, the positions of points on the module's connecting end face in the ship's coordinate system, and the rotation-position transformation matrix, the distance between the two ends of the module is obtained. and modules The new position of the corresponding point on the connecting end face in the global coordinate system will move the module. and modules The distance between the two ends of the cable is obtained by subtracting the new positions of the corresponding points at the connection end in the global coordinate system. Rubber pads act on the module The process of obtaining the total load at the center of mass includes: applying unit relative displacements to the two floating modules connected by the rubber pad in six degrees of freedom directions, and extracting the support reactions acting at the center of mass of the two floating modules respectively, thereby obtaining the equivalent stiffness matrix of the rubber pad; based on the equivalent stiffness matrix and the coordinate transformation matrix from the global coordinate system to the local coordinate system of the connecting system, obtaining the load on the module caused by the rubber pad. Total load on the center of mass.

2. The method for analyzing flexible connectors between complex-configuration floating body modules according to claim 1, characterized in that, The process of obtaining wave excitation force includes: obtaining the wave incident angle and wave frequency, and obtaining the wave excitation force based on the wave incident angle and wave frequency using linear wave theory.

3. The method for analyzing flexible connectors between complex-configuration floating body modules according to claim 1, characterized in that, The process of obtaining the hydrodynamic response of the connector includes: embedding the dynamic control equation of the floating platform into the feedback solution program of the finite element stress analysis, thereby obtaining the hydrodynamic response results. The hydrodynamic response results include at least the time series, the displacement response time series of each float, the relative displacement response time series of each float, the cable tension response time series, the relative displacement time series of the truncated float, the displacement response amplitude of each float, the tension response amplitude of each cable, the relative displacement response amplitude of each float, the short-term predicted value of the relative displacement of each adjacent float, the short-term predicted value of the displacement of each float, the short-term predicted value of the tension of each cable, and the short-term predicted value of the maximum tension of the cable.

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