A mold profile compensation design method and device

Abstract

This invention relates to the field of mold surface technology, and in particular to a mold surface compensation design method and apparatus. The method includes: S100 obtaining the initial deviation displacement H. k,0 S200 obtains the deviation displacement H k S300 obtains dimensionless parameter F obj S400 obtains the optimal compensation factor. This invention replaces previous experimental measurements, eliminates the need to reconstruct the mold surface, and reduces post-demolding shape deviation displacement by over 90%, saving significant funds and time.

Description

Technical Field

[0001] This invention relates to the field of mold surface technology, and in particular to a mold surface compensation design method and device. Background Technology

[0002] In practical engineering, engineers often use the theoretical shape of composite material components as the mold surface. However, after demolding, the actual shape of the composite material component often differs from the theoretical shape. Due to the good stiffness of composite material components, even small shape deviations often require extremely large forced assembly loads. However, such prestressed forced assembly is strictly prohibited in aircraft assembly specifications. Therefore, curing deformation poses a challenge to the manufacturing and assembly of composite material components. To obtain composite material components with high shape accuracy, domestic and foreign composite material manufacturers mainly use the method of modifying the mold surface. However, due to the lack of numerical analysis methods for composite material curing deformation, the compensation amount of the mold surface is currently mainly estimated by empirical rules. When the shape of the composite material component is relatively simple, the above method may be feasible and can meet basic engineering requirements. However, the structures used in aircraft usually have more complex shapes, not simple flat plates or single-curvature curved plates, but combinations of these shapes. Therefore, the deformation modes of composite material components after demolding include not only springback deformation and warping deformation, but also torsional deformation. In this case, the above empirical method becomes unreliable and high-risk.

[0003] Currently, the patent "A molding method for controlling the curing deformation of hyperboloid skin of composite materials" (CN111923452A) proposes to reduce process deformation by cutting and splicing the R-zone of the layup, but the effect of this method on deformation control is usually limited. The patent "A method for predicting the springback angle of curing deformation of L-shaped composite parts" (CN113221398) first predicts the deformation amount and then eliminates the deformation by overhauling the mold once. However, the result of a single deformation prediction cannot directly obtain the mold surface, because if the mold surface is modified, the initial shape of the part will also change, and the deformation result will definitely be different from the deformation result with the initial shape. Therefore, the model surface design requires an iterative process. The patent "A method for designing the surface of a tooling for thermoforming composite component autoclaves based on finite element analysis" (CN102567582B) improves upon the methods described in the above patents by adding repeated finite element analysis and judgment processes until a tooling surface that meets the accuracy requirements is obtained. However, this method brings a new problem: each repeated finite element analysis not only requires reconstructing the finite element model, but also requires reconstructing the mold surface based on the deformation in the previous step. Reconstructing the finite element model and reconstructing the mold surface greatly increases the difficulty and workload. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a mold surface compensation design method and device.

[0005] To achieve the above and other related objectives, the present invention provides a mold surface compensation design method, comprising the following steps:

[0006] S100 obtains the initial demolded component shape M0 by translating the initial deformation vector D0 based on the initial mold surface S0. The initial deviation displacement H between the initial mold surface S0 and the initial deformation vector D0 is then obtained. k,0 ;

[0007] S200 obtains a compensation vector D1 by inversely multiplying the initial deformation vector D0 by the compensation factor μ, and then translates the initial mold surface S0 by the compensation vector D1 to obtain the compensated model surface S1; the compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component; the deviation displacement H between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. k ;

[0008] S300 based on deviation displacement H k and initial deviation displacement H k,0 Obtain the dimensionless parameter F to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. obj ;

[0009] S400 with F obj The optimal compensation factor is calculated by minimizing the target value.

[0010] In any embodiment of the present invention, in step S100, the coordinates of any node i on the initial mold surface S0 are represented as (x... i ,y i ,z i The initial deformation vector D0 is represented as (Δx) i ,Δy i ,Δz i ), initial deviation displacement H k,0 The model is: In the formula, k is the number of the comparison point, and Δx k ,Δy k ,Δz k This represents the deformation of the comparison point k in the x, y, and z directions.

[0011] In any embodiment of the present invention, in step S200, the coordinates of node i on the compensated model surface S1 are: Where, x′ i ,y′i ,z′ i D1 represents the coordinates of node i on the compensated mold surface S1; D2 represents (Δx′) i ,Δy′ i ,Δz′ i The deviation displacement H k The model is: In the formula, k is the number of the comparison point, (Δx′) k -μΔx k ), (Δy′ k -μΔy k ), (Δz′ k -μΔz k The value represents the deformation of the comparison point k in the x, y, and z directions.

[0012] In any embodiment of the present invention, in step S300, the dimensionless parameter F obj The model is: In the formula, N H This represents the number of comparison points.

[0013] In any embodiment of the present invention, in step S400, F obj The model that minimizes the optimization objective to obtain the corresponding optimal compensation factor is as follows:

[0014] Find(μ);

[0015]

[0016] st0 < μ < 1.5.

[0017] In any embodiment of the present invention, based on the compensation factor μ and F obj The correlation between them is fitted to obtain a model: F obj =aμ 2 +bμ+c, where a, b, and c are coefficients.

[0018] Another aspect of the present invention provides a mold surface compensation device, comprising:

[0019] Initial deformation calculation module: used to obtain the initial deviation displacement H k,0 The initial demolded component shape M0 is obtained by translating the initial mold surface S0 and the initial deformation vector D0. The initial deviation displacement H between the initial mold surface S0 and the initial deformation vector D0 is then obtained. k,0 ;

[0020] Post-compensation deformation calculation module: used to obtain the deviation displacement H. kBased on the inverse of the product of the initial deformation vector D0 and the compensation factor μ, the compensation vector D1 is obtained. The initial mold surface S0 is translated by the compensation vector D1 to obtain the compensated model surface S1. The compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component. The deviation displacement H between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. k ;

[0021] Dimensionless parameter calculation module: used to obtain the dimensionless parameter F obj According to the deviation displacement H k and initial deviation displacement H k,0 Obtain the dimensionless parameter F to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. obj ;

[0022] Optimal Compensation Factor Calculation Module: Used to obtain the optimal compensation factor, denoted as F. obj The optimal compensation factor is calculated by minimizing the target value.

[0023] In any embodiment of the present invention, in the initial deformation calculation module, the coordinates of any node i on the initial mold surface S0 are represented as (x... i ,y i ,z i The initial deformation vector D0 is represented as (Δx) i ,Δy i ,Δz i ), initial deviation displacement H k,0 The model is: In the formula, k is the number of the comparison point, and Δx k ,Δy k ,Δz k This represents the deformation of the comparison point k in the x, y, and z directions.

[0024] In any embodiment of the present invention, in the post-compensation deformation calculation module, the coordinates of node i on the post-compensation model surface S1 are: Where, x′ i ,y′ i ,z′ i D1 represents the coordinates of node i on the compensated mold surface S1; D2 represents (Δx′) i ,Δy′ i ,Δz′ i The deviation displacement H k The model is: In the formula, k is the number of the comparison point, (Δx′) k -μΔx k ), (Δy′k -μΔy k ), (Δz′ k -μΔz k The value represents the deformation of the comparison point k in the x, y, and z directions.

[0025] In any embodiment of the present invention, in the dimensionless parameter calculation module, the dimensionless parameter F obj The model is: In the formula, N H This represents the number of comparison points.

[0026] In any embodiment of the present invention, in the optimal compensation factor calculation module, F obj The model that minimizes the optimization objective to obtain the corresponding optimal compensation factor is as follows:

[0027] Find(μ);

[0028]

[0029] st0 < μ < 1.5.

[0030] In any embodiment of the present invention, based on the compensation factor μ and F obj The correlation between them is fitted to obtain a model: F obj =aμ 2 +bμ+c, where a, b, and c are coefficients.

[0031] Another aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the present invention.

[0032] Another aspect of the present invention provides a mold surface compensation device, the device comprising: a memory and a processor; the memory storing a computer program thereon; the processor being used to execute the computer program stored in the memory, wherein the program, when executed, implements the method described in the present invention.

[0033] The present invention achieves the following beneficial effects:

[0034] 1) The curing deformation of composite material structural parts is predicted based on finite element numerical simulation technology, which replaces the previous experimental measurement and saves a lot of money and time.

[0035] 2) To address the problem of mold surface compensation, a mathematical optimization method is introduced, and a mold surface compensation design method based on compensation factors is proposed.

[0036] 3) The mold surface compensation design method based on compensation factors replaces the previous iterative process with compensation factors, thus eliminating the need to reconstruct the mold surface and saving a significant amount of computation time.

[0037] 4) Typical calculation examples show that the mold surface compensation design method based on compensation factor proposed in this patent solves the problem of poor shape accuracy of composite material components after demolding, completes the mold surface optimization design of composite material U-beam, and reduces the shape deviation displacement after demolding by more than 90%. Attached Figure Description

[0038] Figure 1 This diagram shows the relationship between the theoretical shape, the mold surface, and the shape of the components before and after demolding. Figure 1 In the diagram, 1 represents the three-dimensional theoretical model of the composite material component, 11 represents the theoretical shape, 2 represents the mold, 21 represents the mold surface, 3 represents the composite material component after demolding, and 31 represents the deformed shape of the component after demolding.

[0039] Figure 2 This demonstrates the basic idea behind the mold surface compensation design method.

[0040] Figure 3 The diagram shows the calculation flow for curing deformation in the initial state.

[0041] Figure 4 The diagram shows the calculation flow for curing deformation under compensated conditions.

[0042] Figure 5 This is a flowchart illustrating the mold surface compensation design method. Detailed Implementation

[0043] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0044] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0045] This invention describes and explains the theoretical shape 11, mold surface 21, component shape before curing, and component shape 31 after demolding of composite material components. The mold process type determines the selection of the theoretical shape of the composite material component. Taking a composite U-shaped beam as an example, when using a male mold process, the inner surface of the three-dimensional theoretical model of the U-shaped beam is taken as the theoretical shape 21; when using a female mold process, the outer surface is taken as the theoretical shape. Figure 1 As shown. According to existing manufacturing processes, the mold surface 21 is usually based on the theoretical shape 11 of the component, so the mold surface 21 generally maintains the same shape as the theoretical shape 11. Before curing, the composite prepreg is laid layer by layer on the mold surface, and the prepreg adheres to the mold surface, so the shape of the component before curing is consistent with the mold surface. Due to the influence of factors such as thermal shrinkage, chemical shrinkage, and mold action during the curing process, the shape of the component will deform after demolding, so the shape of the component after demolding is inconsistent with the mold surface. The relationship between the mold surface and the component shape is as follows. Figure 1 As shown.

[0046]

[0047] As the above analysis shows, if the theoretical shape of the composite component is directly used as the mold surface, due to the inevitable curing deformation of the composite material, there will often be a certain deviation between the demolded component's shape and the theoretical shape. To improve the shape accuracy of the demolded component, this invention proposes a mold surface compensation design method based on a compensation factor. The ultimate goal of this method is to find a target shape that pre-considers the influence of curing deformation, enabling a smaller deviation between the demolded component's shape and the theoretical shape. Figure 2 As shown, where Figure 2 (a) The theoretical shape is used as the mold surface. Figure 2 (b) The target shape is used as the mold surface. Based on this, the present invention was completed.

[0048] See Figure 5 This invention provides a mold surface compensation design method, comprising the following steps:

[0049] S100 obtains the initial demolded component shape M0 by translating the initial deformation vector D0 based on the initial mold surface S0. The initial deviation displacement H between the initial mold surface S0 and the initial deformation vector D0 is then obtained. k,0 ;

[0050] S200 obtains a compensation vector D1 by inversely multiplying the initial deformation vector D0 by the compensation factor μ, and then translates the initial mold surface S0 by the compensation vector D1 to obtain the compensated model surface S1; the compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component; the deviation displacement H between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. k ;

[0051] S300 based on deviation displacement H k and initial deviation displacement H k,0 Obtain the dimensionless parameter F to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. obj ;

[0052] S400 with F obj The optimal compensation factor is calculated by minimizing the target value.

[0053] Step S100 involves translating the initial deformation vector D0 based on the initial mold surface S0 to obtain the initial demolded component shape M0, and then obtaining the initial deviation displacement H between the initial mold surface S0 and the initial deformation vector D0. k,0 In a specific embodiment, the theoretical shape is used as the initial mold surface S0. The initial mold surface S0 represents the shape of the component before curing. The initial deformation vector D0 and the deformed shape M1 of the component after demolding can be calculated using finite element analysis (FEA). Specifically, finite element analysis (FEA) uses mathematical approximation methods to simulate real physical systems (geometry and load conditions). Using simple yet interacting elements (i.e., units), a real system with an infinite number of unknowns can be approximated with a finite number of unknowns. Existing software can be used for finite element analysis (FEA). See [link to relevant documentation]. Figure 3 In finite element analysis, the initial mold surface and the shape of the component are represented by discretized node coordinates in a global coordinate system. The coordinates of any node i on the initial mold surface S0 are represented as (x... i ,y i ,z i The initial deformation vector D0 is represented as (Δx) i ,Δy i ,Δz i Several key nodes were selected as comparison points, and their initial deviation displacement H was determined. k,0 for:

[0054]

[0055] In equation (1), k represents the number of the comparison point. Δxk ,Δy k ,Δz k This represents the deformation of the comparison point k in the three principal directions of x, y, and z.

[0056] In steps S200–S400, a surrogate model is established using the compensation factor as the design variable. Specifically:

[0057] Step S200 involves obtaining a compensation vector D1 by inversely multiplying the initial deformation vector D0 by the compensation factor μ; translating the initial mold surface S0 by the compensation vector D1 to obtain the compensated model surface S1; translating the compensated model surface S1 by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component; and obtaining the deviation displacement H between the deformed shape M1 of the demolded component and the initial mold surface S0. k In a specific embodiment, the initial mold surface is first compensated. The compensation vector D1 is defined as follows: D1 is equal to the inverse of the product of the compensation factor μ and the initial deformation vector D0, i.e.

[0058] D1=D0×μ (2)

[0059] Then, the compensation vector D1 is superimposed on the initial mold surface S0 to obtain the compensated mold surface S1. See [link to relevant documentation]. Figure 4 According to equation (2), the coordinates of node i on the compensated mold surface S1 are:

[0060]

[0061] In equation (3), x′ i ,y′ i ,z′ i This represents the coordinates of node i on the compensated mold surface S1. See also... Figure 4 Using the compensated mold surface S1 as the shape of the component before curing, the deformed shape M1 of the component after demolding is obtained through curing deformation FEA. The deformation vector at this time is called the compensated deformation vector D2, denoted as (Δx′). i ,Δy′ i ,Δz′ i In some embodiments, the compensated mold surface S1 can be used as the shape of the component before curing. Based on the compensated deformation vector D2, the deformed shape M1 of the component after demolding can be obtained through FEA. Alternatively, the compensated mold surface S1 can be used as the shape of the component before curing. Based on the deformed shape M1 of the component after demolding, the compensated deformation vector D2 can be obtained through FEA.

[0062] Further obtain the deviation displacement H k The deviation displacement H kLet H be the deviation displacement between the deformed shape M1 of the demolded component and the initial mold surface S0. H is the deviation displacement H of the comparison point k on the deformed shape M1 of the demolded component relative to the theoretical shape. k for:

[0063]

[0064] In equation (4), k is the number of the comparison point, (Δx′) k -μΔx k ), (Δy′ k -μΔy k ), (Δz′ k -μΔz k The value represents the deformation of the comparison point k in the x, y, and z directions.

[0065] Step S300 is based on the deviation displacement H k and initial deviation displacement H k,0 Obtain the dimensionless parameter F to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. obj In a specific embodiment, the initial mold surface S0 is the theoretical shape T. obj The definition can comprehensively reflect the degree of deviation between the deformed shape M1 of the component after demolding and the theoretical shape, that is:

[0066]

[0067] In equation (5), N H The number of comparison points. Parameter F obj It can characterize the degree of deviation between the deformed shape M1 and the theoretical shape T of the component after demolding, when F obj A smaller value indicates a smaller deviation between M1 and T; conversely, a larger value indicates a larger deviation between M1 and T.

[0068] Step S400 is F obj Minimize the corresponding optimal compensation factor to optimize the process. More specifically, since the value of the compensation factor determines the quality of the component's shape accuracy after demolding, the mold surface compensation problem is transformed into a problem with the compensation factor μ as the design variable and F as the optimization factor. obj An optimization problem with the objective of minimizing. Based on F... obj The mathematical model for minimizing the optimization objective to obtain the corresponding optimal compensation factor is as follows:

[0069]

[0070] To improve solution efficiency, a surrogate model technique is introduced to establish a surrogate model of compensation factor and objective function. A sample point set is selected from the design space of the compensation factor μ, and then solidification deformation FEA calculations are performed sequentially. The objective function F is obtained from the calculation results. obj Numerical analysis revealed that the surrogate model built using a second-order polynomial achieved a better fit in practical applications.

[0071] Therefore, based on the compensation factor μ and F obj The correlation between them was used to fit a model between them:

[0072] F obj =aμ 2 +bμ+c (7)

[0073] In equation (7), a, b, and c are the undetermined coefficients of the quadratic polynomial. By finding the minimum value of the quadratic polynomial, the optimal compensation factor can be obtained. Substituting the optimal compensation factor into equation (3), the optimal compensation profile can be obtained.

[0074] This invention also provides a mold surface compensation device, comprising:

[0075] Initial deformation calculation module: used to obtain the initial deviation displacement H k,0 The initial demolded component shape M0 is obtained by translating the initial mold surface S0 and the initial deformation vector D0. The initial deviation displacement H between the initial mold surface S0 and the initial deformation vector D0 is then obtained. k,0 ;

[0076] Post-compensation deformation calculation module: used to obtain the deviation displacement H. k Based on the inverse of the product of the initial deformation vector D0 and the compensation factor μ, the compensation vector D1 is obtained. The initial mold surface S0 is translated by the compensation vector D1 to obtain the compensated model surface S1. The compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component. The deviation displacement H between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. k ;

[0077] Dimensionless parameter calculation module: used to obtain the dimensionless parameter F obj According to the deviation displacement H k and initial deviation displacement H k,0 Obtain the dimensionless parameter F to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. obj ;

[0078] Optimal Compensation Factor Calculation Module: Used to obtain the optimal compensation factor, denoted as F. objThe optimal compensation factor is calculated by minimizing the target value.

[0079] Specifically, in the initial deformation calculation module, the theoretical shape is used as the initial mold surface S0. The initial mold surface S0 represents the shape of the component before curing. The initial deformation vector D0 and the deformed shape M1 of the component after demolding can be calculated using finite element analysis (FEA). Finite element analysis (FEA) uses mathematical approximation methods to simulate real physical systems (geometry and load conditions). Using simple yet interacting elements (i.e., units), a real system with an infinite number of unknowns can be approximated with a finite number of unknowns. Existing software can be used for finite element analysis (FEA). See also... Figure 3 In finite element analysis, the initial mold surface and the shape of the component are represented by discretized nodal coordinates in the global coordinate system. The coordinates of any node i on the initial mold surface S0 are represented as (x... i ,y i ,z i The initial deformation vector D0 is represented as (Δx) i ,Δy i ,Δz i Several key nodes were selected as comparison points, and their initial deviation displacement H was determined. k,0 for:

[0080]

[0081] In equation (1), k represents the number of the comparison point. Δx k ,Δy k ,Δz k This represents the deformation of the comparison point k in the three principal directions of x, y, and z.

[0082] In the compensation deformation calculation module, dimensionless parameter calculation module, and optimal compensation factor calculation module, a surrogate model with the compensation factor as the design variable is established. Specifically:

[0083] In a specific embodiment of the post-compensation deformation calculation module, the initial mold surface is first designed for compensation. The compensation vector D1 is defined as: D1 is equal to the inverse of the product of the compensation factor μ and the initial deformation vector D0, i.e.

[0084] D1=D0×μ (2)

[0085] Then, the compensation vector D1 is superimposed on the initial mold surface S0 to obtain the compensated mold surface S1. See [link to relevant documentation]. Figure 4 According to equation (2), the coordinates of node i on the compensated mold surface S1 are:

[0086]

[0087] In equation (3), x′ i ,y′ i ,z′ i This represents the coordinates of node i on the compensated mold surface S1. See also... Figure 4 Using the compensated mold surface S1 as the shape of the component before curing, the deformed shape M1 of the component after demolding is obtained through curing deformation FEA. The deformation vector at this time is called the compensated deformation vector D2, denoted as (Δx′). i ,Δy′ i ,Δz′ i In some embodiments, the compensated mold surface S1 can be used as the shape of the component before curing. Based on the compensated deformation vector D2, the deformed shape M1 of the component after demolding can be obtained through FEA. Alternatively, the compensated mold surface S1 can be used as the shape of the component before curing. Based on the deformed shape M1, the compensated deformation vector D2 can be obtained through FEA.

[0088] Furthermore, the deviation displacement H is obtained. k The deviation displacement H k Let H be the deviation displacement between the deformed shape M1 of the demolded component and the initial mold surface S0. H is the deviation displacement H of the comparison point k on the deformed shape M1 of the demolded component relative to the theoretical shape. k for:

[0089] In equation (4), k is the number of the comparison point, (Δx′) k -μΔx k ), (Δy′ k -μΔy k ), (Δz′ k -μΔz k The value represents the deformation of the comparison point k in the x, y, and z directions.

[0090] In a specific embodiment of the dimensionless parameter calculation module, the dimensionless parameter F is obtained. obj The dimensionless parameter F obj This characterizes the deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. The initial mold surface S0 is the theoretical shape T. obj The definition can comprehensively reflect the degree of deviation between the deformed shape M1 of the component after demolding and the theoretical shape, that is:

[0091]

[0092] In equation (5), N H The number of comparison points. Parameter F objIt can characterize the degree of deviation between the deformed shape M1 and the theoretical shape T of the component after demolding, when F obj A smaller value indicates a smaller deviation between M1 and T; conversely, a larger value indicates a larger deviation between M1 and T.

[0093] The compensation factor calculation module obtains the optimal compensation factor, with F as the key factor. obj Minimizing the corresponding optimal compensation factor is the optimization objective. Since the value of the compensation factor determines the accuracy of the component's shape after demolding, this chapter transforms the mold surface compensation problem into a problem where the compensation factor μ is the design variable, and F... obj An optimization problem with the objective of minimizing. Based on F... obj The mathematical model for minimizing the optimal compensation factor to obtain the corresponding optimal compensation factor is as follows:

[0094]

[0095] To improve solution efficiency, a surrogate model technique is introduced to establish a surrogate model of compensation factor and objective function. A sample point set is selected from the design space of the compensation factor μ, and then solidification deformation FEA calculations are performed sequentially. The objective function F is obtained from the calculation results. obj Numerical analysis revealed that the surrogate model built using a second-order polynomial achieved a better fit in practical applications.

[0096] Therefore, based on the compensation factor μ and F obj The correlation between them was used to fit a model between them:

[0097] F obj =aμ 2 +bμ+c (7)

[0098] In equation (7), a, b, and c are the undetermined coefficients of the quadratic polynomial. By finding the minimum value of the quadratic polynomial, the optimal compensation factor can be obtained. Substituting the optimal compensation factor into equation (3), the optimal compensation profile can be obtained.

[0099] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the mold surface compensation design method of this invention.

[0100] As will be understood by those skilled in the art, all or part of the steps of the above-described method embodiments can be implemented using computer program-related hardware. The aforementioned computer program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0101] This invention also provides a mold surface compensation device, the device comprising: a memory and a processor; the memory storing a computer program; the processor executing the computer program stored in the memory, wherein the program, when executed, implements the mold surface compensation design method of this invention.

[0102] The memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device.

[0103] The processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0104] In summary, the method and apparatus provided by this invention are as follows:

[0105] 1) The curing deformation of composite material structural parts is predicted based on finite element numerical simulation technology, which replaces the previous experimental measurement and saves a lot of money and time.

[0106] 2) To address the problem of mold surface compensation, a mathematical optimization method is introduced, and a mold surface compensation design method based on compensation factors is proposed.

[0107] 3) The mold surface compensation design method based on compensation factors replaces the previous iterative process with compensation factors, thus eliminating the need to reconstruct the mold surface and saving a significant amount of computation time.

[0108] 4) Typical calculation examples show that the mold surface compensation design method based on compensation factor proposed in this patent solves the problem of poor shape accuracy of composite material components after demolding, completes the mold surface optimization design of composite material U-beam, and reduces the shape deviation displacement after demolding by more than 90%.

[0109] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0110] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A mold surface compensation design method, characterized in that, Includes the following steps: S100 obtains the initial demolded component shape M0 by translating the initial deformation vector D0 based on the initial mold surface S0. The initial deviation displacement between the initial mold surface S0 and the initial deformation vector D0 is then obtained. ; S200 Obtains the compensation vector D1 based on the inverse of the product of the initial deformation vector D0 and the compensation factor μ. The initial mold surface S0 is translated by the compensation vector D1 to obtain the compensated model surface S1. The compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component. The deviation displacement between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. ; S300 Based on deviation displacement and initial deviation displacement Obtain dimensionless parameters to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. ; S400 Minimize the optimization objective to obtain the corresponding optimal compensation factor; In step S100, the coordinates of any node i on the initial mold surface S0 are represented as follows: The initial deformation vector D0 is represented as Initial deviation displacement The model is: In the formula, k is the number of the comparison point. This indicates the amount of deformation at comparison point k in the x, y, and z directions; In step S200, the coordinates of node i on the compensated model surface S1 are: ;in, D1 represents the coordinates of node i on the compensated mold surface S1; D2 is... The deviation displacement The model is: ； In the formula, k is the number of the comparison point, ( ), ( ), ( () indicates the deformation of the comparison point k in the x, y, and z directions; In step S300, the dimensionless parameter The model is: In the formula, N H This represents the number of comparison points.

2. The mold surface compensation design method as described in claim 1, characterized in that, In step S400, with The model that minimizes the optimization objective to obtain the corresponding optimal compensation factor is as follows: Find ; Min ; s.t. 。 3. The mold surface compensation design method as described in claim 1, characterized in that, Based on the compensation factor μ and The correlation between them was used to fit a model between them: , where a, b and c are coefficients.

4. A mold surface compensation device, characterized in that, include: Initial deformation calculation module: used to obtain initial deviation displacement. The initial demolded component shape M0 is obtained by translating the initial mold surface S0 and the initial deformation vector D0. The initial deviation displacement between the initial mold surface S0 and the initial deformation vector D0 is then obtained. ; Post-compensation deformation calculation module: used to obtain the deviation displacement. Based on the inverse of the product of the initial deformation vector D0 and the compensation factor μ, the compensation vector D1 is obtained. The initial mold surface S0 is translated by the compensation vector D1 to obtain the compensated model surface S1. The compensated model surface S1 is then translated by the compensation deformation vector D2 to obtain the deformed shape M1 of the demolded component. The deviation displacement between the deformed shape M1 of the demolded component and the initial mold surface S0 is obtained. ; Dimensionless parameter calculation module: used to obtain dimensionless parameters According to the deviation displacement and initial deviation displacement Obtain dimensionless parameters to characterize the degree of shape deviation between the deformed shape M1 of the component after demolding and the initial mold surface S0. ; Optimal compensation factor calculation module: Used to obtain the optimal compensation factor, in order to Minimize the optimization objective to obtain the corresponding optimal compensation factor; In the initial deformation calculation module, the coordinates of any node i on the initial mold surface S0 are represented as follows: The initial deformation vector D0 is represented as Initial deviation displacement The model is: In the formula, k is the number of the comparison point. This indicates the amount of deformation at comparison point k in the x, y, and z directions; In the compensation deformation calculation module, the coordinates of node i on the compensated model surface S1 are: ;in, D1 represents the coordinates of node i on the compensated mold surface S1; D2 is... The deviation displacement The model is: ； In the formula, k is the number of the comparison point, ( ), ( ), ( () indicates the deformation of the comparison point k in the x, y, and z directions; In the dimensionless parameter calculation module, the dimensionless parameter The model is: In the formula, N H This represents the number of comparison points.

5. The mold surface compensation device as described in claim 4, characterized in that, In the optimal compensation factor calculation module, with The model that minimizes the optimization objective to obtain the corresponding optimal compensation factor is as follows: Find ; Min ; s.t. 。 6. The mold surface compensation device as described in claim 4, characterized in that, Based on the compensation factor μ and The correlation between them was used to fit a model between them: , where a, b and c are coefficients.

7. A mold surface compensation device, characterized in that, The device includes: a memory and a processor; the memory stores a computer program thereon; the processor is configured to execute the computer program stored in the memory, wherein the program, when executed, implements the method as described in any one of claims 1 to 3.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1 to 3.

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