Simulation method and system applicable to fishing rod action curve calculation

Abstract

This invention discloses a simulation method and system suitable for calculating the action curve of fishing rods. The simulation method includes acquiring input information, which includes at least one of the following: material information, mold information, layup information, and load information of the target fishing rod; performing equivalence based on the input information, converting the variable cross-section structure of the target fishing rod into multiple segments of sequentially arranged constant cross-section structures, and simultaneously acquiring the geometric dimensions and stiffness information of each constant cross-section structure; calculating the deformation displacement of different parts of the target fishing rod to obtain the simulation result of the action curve of the target fishing rod. The simulation method of this invention is simple and efficient, and can effectively and quickly simulate the action curve of fishing rods, thereby improving the accuracy and efficiency of fishing rod performance verification.

Description

Technical Field

[0001] This invention relates to simulation methods, and more particularly to a simulation method and system suitable for calculating the action curve of a fishing rod. Background Technology

[0002] The action curve refers to the bending line formed by a fishing rod when subjected to a vertical load at its end. The action curve can be used to evaluate the magnitude of a fishing rod's action. Currently, research on action curves mainly employs the finite element method and the deflection curve governing equation solution method. Fishing rod manufacturers primarily rely on performance testing to adjust and obtain a suitable action curve. Finite element method analysis involves a series of fixed processes, including modeling, defining and assigning material properties, mesh generation, defining analysis steps, defining loads and boundary conditions, and defining assembly and interaction relationships. This process is time-consuming, cumbersome, and requires highly skilled designers. While experimental verification of the action curve obtained using this method yields accurate curves, the need for rod manufacturing significantly increases costs related to molds, design, and materials. Furthermore, the obtained action curves often do not quickly meet design requirements, necessitating repeated iterative testing, resulting in substantial waste of time, manpower, and resources, and low efficiency.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a simulation method and system suitable for calculating the action curve of fishing rods. The simulation results are accurate and easy to use, providing a design basis for the layering and structural design of fishing rods, simplifying the design process and saving design costs.

[0005] To achieve the above objectives, embodiments of the present invention provide a simulation method suitable for calculating the action curve of a fishing rod, including acquiring input information, which includes at least one of the following: material information, mold information, layup information, and load information of the target fishing rod; performing equivalence based on the input information, converting the variable cross-section structure of the target fishing rod into multiple segments of sequentially arranged constant cross-section structures, and acquiring the geometric dimensions and stiffness information of each segment of the constant cross-section structure; calculating the deformation displacement of different parts of the target fishing rod, and obtaining the simulation result of the action curve of the target fishing rod.

[0006] In one or more embodiments of the present invention, the material information includes at least one of the following: material serial number, material name, axial elastic modulus E1, transverse elastic modulus E2, and Poisson's ratio ν. 21 Shear modulus G 12 Single layer thickness t.

[0007] In one or more embodiments of the present invention, the mold information includes at least any of the following: serial number / number of fishing rod sections, first fine end diameter dm1 and section length lm1, second fine end diameter dm2 and section length lm2, third fine end diameter dm3, total length Lm, front cut length Qq, material length Lsc, and fitting length Qh.

[0008] In one or more embodiments of the present invention, the layup information includes at least any of the following: layup number, material name, material number, number of fishing rod sections, front width B1, rear width B2, first length L1, and second length L2.

[0009] In one or more embodiments of the present invention, the load information includes at least the fishing weight. The fishing weight here can be a simulated fishing weight from an experiment, or an actual load such as the weight of a fish or a weight.

[0010] In one or more embodiments of the present invention, the equivalent multi-segment, sequentially arranged constant cross-section structure forms an inner and outer diameter matrix Elm as follows:

[0011]

[0012] Where m is the number of layers in the first section of the fishing rod, n is the number of units in the first section of the fishing rod, s is the number of sections, e is the number of layers in the s-th section of the fishing rod, and w is the number of units in the s-th section of the fishing rod.

[0013] 10. In one or more embodiments of the present invention, the stiffness information is calculated based on the geometric dimensions and material modulus information of the constant cross-section structure, thus obtaining the bending stiffness EI of each constant cross-section structure. Therefore, the calculation expression for the bending stiffness EIi of the i-th constant cross-section beam element is:

[0014]

[0015] Among them, E 等效i Let I be the equivalent modulus of the i-th constant cross-section beam element. zi Let D be the moment of inertia of the i-th constant cross-section beam element about the neutral axis z. i Let d be the outer diameter of the beam element. i Let y be the inner diameter of the beam element, and y be the vertical displacement of the element node.

[0016] In one or more embodiments of the present invention, the target fishing rod is made of carbon fiber.

[0017] In one or more embodiments of the present invention, a system is used to run the simulation method described above for calculating the action curve of a fishing rod.

[0018] Compared with existing technologies, the simulation method and system for calculating the action curve of fishing rods according to embodiments of the present invention can provide a theoretical design foundation in the early stages of design, prevent blind experimentation, reduce the number of trial and error, thereby reducing testing and design costs, shortening the R&D cycle, and improving R&D efficiency. Compared with finite element simulation, this simulation method does not require the installation and debugging of large-scale finite element simulation software, has low hardware requirements, and because this simulation method is specifically designed for fishing rod design, it uses parameters and settings commonly used in the fishing rod design process, making it simple and quick to learn. It avoids the need for professional training in large-scale finite element simulation software, has lower requirements for advanced professional skills of designers, and is more convenient to use. Using finite element software to perform simulation analysis of a fishing rod, from modeling, assigning material and cross-sectional properties, meshing, to submitting calculations and post-processing, takes about 2 hours in total. However, using the fishing rod action curve simulation method of the present invention, it only takes 8 minutes, including 3 minutes for inputting information in the input module and 5 minutes for submitting calculations and the calculation process, effectively demonstrating the high efficiency of the present invention. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the material information portion of the input module of a simulation method according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the mold information portion of the input module of the simulation method according to an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the layup information portion of the input module of the simulation method according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the load information portion of the input module of the simulation method according to an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure corresponding to each parameter of the mold information in the simulation method according to an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the structure corresponding to each parameter of the layup information in the simulation method according to an embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of the structure corresponding to each parameter of the inner and outer diameter data matrix of a constant cross-section beam element according to a simulation method of an embodiment of the present invention.

[0026] Figure 8 This is a schematic cross-sectional view of a constant cross-section beam element according to a simulation method of an embodiment of the present invention.

[0027] Figure 9This is a schematic cross-sectional view of a constant cross-section beam element according to a simulation method of an embodiment of the present invention.

[0028] Figure 10 This is a tone curve diagram of the output module according to an embodiment of the present invention;

[0029] Figure 11 This is a layup information diagram of an output module according to an embodiment of the present invention;

[0030] Figure 12 This is a bending stiffness curve of the output module according to an embodiment of the present invention. Detailed Implementation

[0031] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0032] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0033] like Figures 1 to 12 As shown, a simulation method and system for calculating the action curve of a fishing rod according to a preferred embodiment of the present invention are as follows:

[0034] In the implementation of the fishing rod action curve simulation method, the operating system can include an input module, a calculation module, and an output module. After inputting material data, mold data, and layup data, the calculation module will process the variable cross-section beam (i.e., variable cross-section structure, hereinafter the same) of the target fishing rod into multiple constant cross-section beam elements (i.e., constant cross-section structure, hereinafter the same) based on the input information, and obtain the geometric dimensions and equivalent stiffness information of each constant cross-section beam element. Through the large deflection cantilever beam theory, the deformation displacement of different parts of the fishing rod is obtained. Finally, the output module plots the calculated displacement values ​​to obtain the action curve of the fishing rod.

[0035] In the simulation of fishing rod action curves, the input module can include four parts: material information, mold information, layup information, and load information. The material information section is shown below. Figure 1 This includes the material serial number, material name, axial elastic modulus E1, transverse elastic modulus E2, Poisson's ratio ν21, shear modulus G12, and single-layer thickness t. The mold information section is shown as follows: Figure 2 This includes the serial number / number of fishing rod sections, the diameter of the first thin end (dm1) and the section length (lm1), the diameter of the second thin end (dm2) and the section length (lm2), the diameter of the third thin end (dm3), the total length (Lm), the front cut length (Qq), the material length (Lsc), and the fitting length (Qh). For the meaning of each parameter, please refer to [link / reference]. Figure 5 The ply information is shown in the following section. Figure 3 It includes the ply number, material name, material number, number of fishing rod sections, front width B1, rear width B2, first length L1, and second length L2. For details on the meaning of each parameter, please refer to [link / reference]. Figure 6 The load information section is shown as follows: Figure 4 It includes the fishing weight.

[0036] The calculation principle of the computation module in the fishing rod action curve simulation method is as follows:

[0037] Step 1: Based on the mold size, single layer thickness and ply information data, determine the number of ply layers and inner and outer diameters of each ply layer at the front and rear ends of each section of the fishing rod, and use the linear interpolation method to determine the inner and outer diameters of each ply layer of each constant cross-section beam unit.

[0038] The inner and outer diameter data matrix for each constant cross-section beam element is as follows:

[0039]

[0040] Where m is the number of layers in the first section of the fishing rod, n is the number of units in the first section of the fishing rod, s is the number of sections, e is the number of layers in the s-th section of the fishing rod, and w is the number of units in the s-th section of the fishing rod.

[0041] Then we have d1 11 d1 is the inner diameter of the first unit of the first layer of the first section. 1n d1 is the inner diameter of the nth unit of the first layer of the first section. m1 d1 is the inner diameter of the first unit of the m-th layer in the first section. mn d1 is the inner diameter of the nth unit in the mth layer of the first section. (m+1)1 Let d1 be the outer diameter of the first unit in the m-th layer of the first section. (m+1)n ds is the outer diameter of the nth unit in the mth layer of the first section; 11 ds is the inner diameter of the first unit of the first layer of the first ply in section s. 1w Let ds be the inner diameter of the w-th unit of the first layer of the s-th section. e1 ds is the inner diameter of the first unit of the e-th layer in section s. ew Let ds be the inner diameter of the w-th unit in the e-th layer of the s-th section. (e+1)1 ds is the outer diameter of the first unit in the e-th layer of the s-th section. (e+1)w Let w be the outer diameter of the w-th unit in the e-th layer of the s-th section. See details. Figure 7 .

[0042] Step 2: Combine the inner and outer diameters and material modulus information of each ply of the obtained constant cross-section beam element, and obtain the bending stiffness EI of each constant cross-section beam element by calculating the equivalent modulus E and the moment of inertia Iz about the center plane.

[0043] The formula for calculating the flexural stiffness EIi of the i-th constant section beam element is:

[0044]

[0045] Among them, E 等效i Let I be the equivalent modulus of the i-th constant cross-section beam element. zi Let be the moment of inertia of the i-th constant section beam element about the neutral axis z (see...) Figure 8 Di is the outer diameter of the beam element, and di is the inner diameter of the beam element.

[0046] Step 3: Based on the fishing weight information input in the load information section, obtain the bending moment value at the base of the fishing rod, and use the cantilever beam large deformation theory to iteratively calculate the deformation of each constant section beam element, and finally obtain the final horizontal and vertical deformation of each element.

[0047] The formula for calculating the deformation of an n-segment large deformation cantilever beam is as follows:

[0048]

[0049] Where y is the vertical displacement of the element node, x is the horizontal displacement of the element node, ρ is the radius of curvature of the element, and α is the angle between the tangent of the element node and the x-axis.

[0050] In the above formula, ρ and α are both unknowns, and ρ and α must satisfy the following requirement:

[0051]

[0052] Where M is the bending moment of the element, F is the concentrated load on the free end of the beam, l is the element length, L is the total length of the fishing rod, X is the horizontal displacement caused by the concentrated load on the end of the fishing rod, c is the distance from the element node to the fixed end when the fishing rod is not deformed, and c' is the horizontal position of the node where c is located after deformation. The geometric meaning of each parameter is given in [reference needed]. Figure 9 As shown.

[0053] Therefore, the unknown quantity in the calculation formula is X. The solution to cn' in the above formula is a loop structure and cannot be solved directly. Therefore, an approximation is used here, the approximation being as follows:

[0054]

[0055] The X value cannot be directly obtained. It can be adapted based on the condition that the free end bending moment is 0. An initial X value is selected for iterative calculation, so that the calculated free end bending moment value gradually approaches 0. The response X value that makes the free end bending moment value sufficiently close to 0 is selected as the final calculation value. Substitute it into the previous calculation formula to obtain the horizontal and vertical displacement values ​​of all unit nodes of the fishing rod.

[0056] The output module of the fishing rod action curve simulation method includes an action curve graph; see details. Figure 9 .

[0057] Based on the above, in order to facilitate the rapid assignment of material properties, some engineering constant data of commonly used materials are preset (such as: material performance data of T300 grade carbon fiber unidirectional prepreg, material performance data of M40J grade carbon fiber unidirectional prepreg, etc.), and a custom material property function is added. A material property retrieval module is added to the layup data information, so that existing or custom engineering constant data can be directly retrieved when assigning layup information, thereby improving the assignment efficiency.

[0058] Building upon the foregoing, to more easily understand the deformation and stiffness information of the designed fishing rod, the output module's output information includes not only the tone curve (see...) but also... Figure 10 It also adds a layer information diagram (see) Figure 11 ) and bending stiffness curve (see Figure 12 The output includes a layer information graph that reflects the layer sequence and thickness of each section of the fishing rod, and a bending stiffness curve that reflects the overall bending stiffness of the fishing rod.

[0059] Based on the above, in order to better reflect the influence of the connecting pads between rod sections on the stiffness of the fishing rod, angle information is added when inputting the layup information. An angle of 0 degrees indicates a pad with the grain, and an angle of 90 degrees indicates a pad with the grain. The pad size is input in the same way as the normal layup.

[0060] Building upon the aforementioned improvements, to enhance computational efficiency and reduce computation time, cell size information is added to the input module. This allows for adjustment of the cell size based on usage needs. Larger cell sizes are used for computational requirements that demand higher efficiency but lower precision, while smaller cell sizes are used for computational requirements that demand higher precision but lower efficiency. This enables optimization and adjustment based on actual usage requirements.

[0061] In the fishing rod action curve calculation and simulation system, the output module contains an action curve graph, which can be used to calculate and verify the performance of the target fishing rod.

[0062] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A simulation method suitable for fish rod tuning curve calculation, characterized by, The method comprises the following steps: acquiring input information, the input information including one of material information, mold information, layer information and load information of a target fishing rod; equivalent according to the input information, equivalent the variable cross-section structure of the target fishing rod into a plurality of constant cross-section structures arranged in sequence, and acquiring the geometric size and stiffness information of each constant cross-section structure; the inner and outer diameter matrix Elem formed by the plurality of constant cross-section structures arranged in sequence is: ； wherein m is the number of plies of the first section of the fishing rod, n is the number of units of the first section of the fishing rod, s is the number of nodes, e is the number of plies of the s-th section of the fishing rod, w is the number of units of the s-th section of the fishing rod, d1 11 is the inner diameter of the first unit of the first layer of the first section, d1 1n is the inner diameter of the n-th unit of the first layer of the first section, d1 m1 is the inner diameter of the first unit of the m-th layer of the first section, d1 mn is the inner diameter of the n-th unit of the m-th layer of the first section, d1 (m+1)1 is the outer diameter of the first unit of the m+1-th layer of the first section, d1 (m+1)n is the outer diameter of the n-th unit of the m+1-th layer of the first section; ds 11 is the inner diameter of the first unit of the first layer of the s-th section, ds 1w is the inner diameter of the w-th unit of the first layer of the s-th section, ds e1 is the inner diameter of the first unit of the e-th layer of the s-th section, ds ew is the inner diameter of the w-th unit of the e-th layer of the s-th section, ds (e+1)1 is the outer diameter of the first unit of the e+1-th layer of the s-th section, ds (e+1)w is the outer diameter of the w-th unit of the e+1-th layer of the s-th section; The rigidity information is used to calculate the bending stiffness EI of each constant cross-section structure according to the geometric size and material modulus information of the constant cross-section structure, and then the bending stiffness EI of the ith constant cross-section beam unit is calculated as follows: i The calculation expression of the bending stiffness EI of the ith constant cross-section beam unit is as follows: ； where E 等效i is the equivalent modulus of the ith constant cross-section beam element, I zi is the moment of inertia of the ith constant cross-section beam element about the neutral axis z-axis, D i is the outer diameter of the beam element, d i is the inner diameter of the beam element; according to the fishing weight information input by the load information, obtaining the bending moment value borne by the root of the fishing rod, and through the large deformation theory of cantilever beam, iteratively calculating the deformation of each constant cross-section beam unit, and obtaining the final horizontal and vertical deformation of each unit; obtaining the deformation displacement of different parts of the target fishing rod, and obtaining the simulation result of the tuning curve of the target fishing rod.

2. The simulation method for fish rod performance curve calculation according to claim 1, wherein, The material information at least includes any of the following: material serial number, material name, axial elastic modulus E1, transverse elastic modulus E2, Poisson's ratio v21, shear modulus G12, and single-layer thickness t.

3. The simulation method for fish rod performance curve calculation according to claim 1, wherein, The mold information at least includes any of the following: serial number / fishing rod node number, first thin end diameter dm1 and node length lm1, second thin end diameter dm2 and node length lm2, third thin end diameter dm3, total length Lm, front cutting length Qq, raw material length Lsc, and embedded length Qh.

4. The simulation method for fish rod performance curve calculation according to claim 1, wherein, The layer information at least includes any of the following: layer serial number, material name, material number, fishing rod node number, front end width B1, rear end width B2, first length L1, and second length L2.

5. The simulation method for fish rod performance curve calculation according to claim 1, wherein, The load information at least includes fishing weight.

6. The simulation method for fish rod performance curve calculation according to claim 1, wherein, The material of the target fishing rod is carbon fiber material.

7. A system for running the simulation method for calculating the tuning curve of the fishing rod according to any one of claims 1-6.

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