Preparation method of 3D printed shoes

Abstract

The invention discloses a preparation method of 3D printing shoes, and belongs to the technical field of 3D printing, and the preparation method comprises the following steps: 1, digital modeling: 2, obtaining a complex shoe geometric model with optimal structural performance by optimizing material distribution under given design space, boundary conditions and load conditions according to the mechanical requirements of the shoes; 3, slicing treatment; 4, 3D printing; and 5, adhering ornaments on the shoes by adopting a dual-curing mechanism. In this way, the optimal complex shoe geometric model is generated through digital modeling, under the same load, the sum of the total stress sigma of the 3D printing shoe and the total stress of the entity shoe is the same and is lower than the yield strength sigma y of the material, and the yield strength of the 3D printing shoe is equivalent to that of the entity shoe. According to the method, a complex shoe geometric model with optimal structural performance can be obtained by optimizing material distribution under given design space, boundary conditions and load conditions according to mechanical requirements of shoes.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing, and in particular to a method for preparing 3D printed shoes. Background Art

[0002] In the traditional shoe manufacturing process, the soles are generally made by injection molding, vulcanization and other processes. This results in certain limitations in material selection, structural design, and production efficiency, making it difficult to achieve precise manufacturing of complex structures, and the limited range of material selection makes it difficult to meet consumers' demands for comfort, durability, and personalization.

[0003] With the development of 3D printing technology, 3D printing technology has gradually been applied in the field of high-end customized shoes. For example, Chinese patent CN112690536A discloses a method for making high-end customized shoes based on 3D scanning and 3D printing technology, including: 3D scanning equipment scans feet; other relevant data are measured; a 3D model of the foot is formed; a 3D model of the sole, insole and upper is established; materials for the sole, insole and upper are prepared; the sole, insole and upper are 3D printed; a 3D gluing and laminating device is used to gluing and laminating the joints of the sole and the upper to form the shoe; and the insole is placed inside the formed shoe.

[0004] However, it does not design lattice structures with different densities and shapes in different areas according to the mechanical requirements of the shoe.

[0005] Based on this, the present invention designs a method for preparing 3D printed shoes to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a method for preparing 3D printed shoes.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A method for preparing 3D printed shoes comprises the following steps:

[0009] 1. Digital Modeling

[0010] 1.1. Generate TPMS lattice structure model;

[0011] 1.2. Use deep learning technology to extract features and train models for design data, and establish a mapping relationship between complex geometric shapes and design parameters;

[0012] 1.3. Input the user's parameters, generate a preliminary shoe model, and optimize the structural details through adaptive adjustment;

[0013] 1.4. The user can adjust and optimize the preliminary model in real time through the interactive design platform to obtain a complex shoe geometry model that meets the requirements;

[0014] 1.5. Use optimization algorithms (genetic algorithms) that simulate natural selection and genetics principles to find the best solution by simulating the biological evolution process and generate the best complex shoe geometry model;

[0015] 1.6. Generate the best complex shoe geometry model using genetic algorithm;

[0016] Second, according to the mechanical requirements of the shoe, under the given design space, boundary conditions and load conditions, the complex shoe geometric model with the best structural performance is obtained by optimizing the material distribution; the specific method is as follows:

[0017] 2.1. Optimize the mechanical properties and aesthetics of the shoes by adjusting the parameters of the TPMS lattice structure model;

[0018] 2.2. Design lattice structures of different densities and shapes in different areas according to the functional requirements of the shoes;

[0019] 3. Slice Processing

[0020] 4. 3D printing;

[0021] 5. Use a dual curing mechanism to bond decorations to shoes.

[0022] Furthermore, step three is as follows: use slicing software to perform high-precision slicing on complex shoe geometry models; select a slicing layer thickness of 5-20 microns; use an intelligent support generation algorithm to optimize the support structure; and use different slicing strategies for different areas of the shoe.

[0023] Furthermore, step four is specifically as follows: using 3D printing equipment for printing; dynamically adjusting the laser power and scanning speed according to the functional requirements of different areas of the shoe; real-time monitoring and adjusting the temperature during the printing process; and adding nano-scale additives to the printing substrate.

[0024] Furthermore, the nanoscale additive is a combination of one or more of carbon nanotubes and graphene.

[0025] Furthermore, nanoscale additives account for 8-15% of the total printing material mass.

[0026] Furthermore, step five specifically includes the following steps:

[0027] 5.1. Use dual-curing resin to form the basic structure of the shoe after light curing, while retaining some uncured

[0028] 5.2. Apply uncured dual-curing resin between the shoe body and the decoration to be inlaid, and perform preliminary light-curing bonding by irradiation;

[0029] 5.3. Post-curing the entire shoe to ensure that all adhesive surfaces are firmly bonded.

[0030] Furthermore, a post-processing process is also included.

[0031] Furthermore, the post-processing process includes the following steps:

[0032] 6.1. Use automated support removal equipment to remove the support, ensuring that the surface of the shoe is not damaged;

[0033] 6.2. Use high-energy laser beams to etch and cut the surface of the shoes, and engrave personalized patterns and texts on the surface or inside of the shoes.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The present invention generates an optimal complex shoe geometric model through digital modeling, and under the same load, the total stress σtotal of the 3D printed shoe is the same as the total stress of the solid shoe, and both are lower than the yield strength σy of the material, and the yield strength of the 3D printed shoe is equivalent to that of the solid shoe. The present invention can obtain a complex shoe geometric model with optimal structural performance by optimizing material distribution under given design space, boundary conditions and load conditions according to the mechanical requirements of the shoe. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 This is a geometric model of the sole of a 3D printed shoe of the present invention. The design method of other parts of the shoe is similar. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Embodiment 1

[0040] In some embodiments, please refer to the attached instructions. Figure 1 , a method for preparing 3D printed shoes, comprising the following steps:

[0041] 1. Digital Modeling

[0042] 1.1. Use the design software Grasshopper and the 3D modeling software Rhinoceros for parametric design. Use Python, JavaScript, C / C++ and other computer programming languages, combine multi-level topology optimization and machine learning technology, perform rough and detailed topology optimization, and divide the structure into many small units for discretization. Use the finite element method to calculate the physical quantity of each unit (such as stress, displacement, etc.). Use optimization algorithms (such as genetic algorithms, gradient descent methods, etc.) to find the optimal material distribution solution and generate a TPMS (three-periodic minimum surface) lattice structure model.

[0043] 1.2. Use deep learning technology to extract features and train models for a large amount of design data, and establish a mapping relationship between complex geometric shapes and design parameters; the specific design parameters are as follows:

[0044] 1.2.1. Geometric parameters:

[0045] (1) Dimensional parameters: including length, width, height, diameter, etc. These are the most basic geometric dimensions that directly determine the shape of the object.

[0046] (2) Shape parameters: such as curvature, angle, inclination, etc. These parameters describe the detailed characteristics of the shape of the object and are particularly important for complex geometric shapes.

[0047] (3) Topological structural parameters: In topological optimization, these parameters describe the distribution of materials in the design area, such as the location, size, and shape of holes, which are of great significance for achieving lightweight design.

[0048] 1.2.2 Material property parameters:

[0049] (1) Elastic modulus: describes the material's ability to resist deformation.

[0050] (2) Density: affects the mass and inertial properties of an object.

[0051] (3) Strength: the maximum load-bearing capacity of a material.

[0052] (4) Other physical properties such as thermal conductivity and electrical conductivity are selected according to the specific application scenario.

[0053] 1.2.3 Boundary conditions and loading parameters:

[0054] (1) Constraints: such as fixed constraints and sliding constraints, which describe the movement restrictions of an object in a specific direction.

[0055] (2) Loading conditions: including external effects such as force, torque, temperature field, and electromagnetic field. These conditions determine the stress and deformation state of the object.

[0056] 1.2.4 Design and manufacturing parameters:

[0057] (1) Manufacturing process parameters: such as processing accuracy, surface roughness, etc. These parameters affect the final quality and performance of the product.

[0058] (2) Cost parameters: including material cost, processing cost, assembly cost, etc., which have an important impact on the economic efficiency and market competitiveness of the product.

[0059] 1.2.5 Performance evaluation parameters:

[0060] (1) Mechanical properties: such as strength, stiffness, stability, etc. These parameters directly reflect the product's load-bearing capacity and safety of use.

[0061] (2) Dynamic performance: such as vibration characteristics and dynamic response, which are particularly important for products that require high-speed movement or withstand dynamic loads.

[0062] (3) Other performance parameters such as thermal properties and electromagnetic properties are selected according to specific application scenarios.

[0063] 1.2.6. Deep learning related parameters

[0064] (3) Network structure parameters: such as the number of layers, convolution kernel size, step size, etc. of the convolutional neural network. These parameters determine the complexity and learning ability of the network.

[0065] (4) Optimize algorithm parameters: such as learning rate, batch size, number of iterations, etc. These parameters affect the training efficiency and convergence of the model.

[0066] (5) Regularization parameters: such as L1 regularization and L2 regularization, which are used to prevent model overfitting.

[0067] In practical applications, these parameters need to be reasonably selected and designed according to specific design goals and constraints to obtain the best design effect and performance.

[0068] 1.3. Input the user's parameters to generate a preliminary shoe model, and adaptively adjust the deep learning model by using deep learning models, such as generative adversarial networks (GANs) and variational autoencoders (VAEs), to automatically adjust model parameters and structures during the training process. These models can generate preliminary shoe models based on the parameters input by the user (such as size, style, functional requirements, etc.). During the generation process, the model will continuously and automatically adjust the internal parameters and structure based on the training data and feedback information to optimize the generated model. For example, by adjusting the size, number, or number of network layers of the convolution kernel, the generation effect of the model can be improved. Optimize structural details to ensure the innovation and practicality of the model;

[0069] 1.4. The user can adjust and optimize the preliminary model in real time through the interactive design platform to obtain a complex shoe geometry model that meets the requirements;

[0070] 1.5. Using an optimization algorithm (genetic algorithm) that simulates the principles of natural selection and genetics, we simulate the biological evolution process to find the best solution and generate the best complex shoe geometry model. The specific steps are as follows:

[0071] 1.5.1. Initialize the population:

[0072] Define the encoding method: First, the geometric model parameters of the shoe (such as size, shape, material distribution, etc.) need to be encoded into a genotype (usually a binary string, integer array or floating point array) that the genetic algorithm can process.

[0073] Generate initial population: Randomly generate a certain number of individuals (i.e. shoe design solutions) as the initial population. Each individual represents a possible solution and contains a specific set of genotypes.

[0074] 1.5.2. Evaluate fitness:

[0075] Define the fitness function: According to the design goals (such as comfort, aesthetics, functionality, etc.), define a fitness function to evaluate the pros and cons of each individual. The fitness function converts the individual's genotype into a fitness value. The higher the fitness value, the better the design scheme.

[0076] Calculate fitness: Evaluate each individual in the initial population and calculate its fitness value.

[0077] 1.5.3. Select operation:

[0078] Roulette selection: Based on the fitness value of the individual, a roulette selection method (or other selection methods) is used to select a certain number of individuals from the current population as parents. Individuals with higher fitness values ​​have a greater probability of being selected.

[0079] Elite retention strategy: In order to avoid the loss of excellent individuals during the evolution process, an elite retention strategy can be adopted, that is, the individuals with the highest fitness are directly copied to the next generation population.

[0080] 1.5.4, Crossover (hybridization) operation:

[0081] Define the crossover method: According to the encoding method, define the appropriate crossover method (such as single-point crossover, multi-point crossover, uniform crossover, etc.). The crossover operation simulates the gene recombination process in biological evolution.

[0082] Perform crossover: Perform crossover operation on the selected parent individuals to generate new offspring individuals. The crossover operation helps to explore new areas in the solution space and increase the diversity of the population.

[0083] 1.5.5, mutation operation:

[0084] Define mutation probability and method: Set a smaller mutation probability and define the mutation method (such as bit flipping, random replacement, etc.). The mutation operation simulates the gene mutation process in biological evolution.

[0085] Perform mutation: Randomly mutate certain genes in the offspring individuals to generate new genotypes. The mutation operation helps to jump out of the local optimal solution and increase the globality of the search.

[0086] 1.5.6. Generate a new population:

[0087] The offspring individuals generated after crossover and mutation are merged with the elite retained individuals to form a new population.

[0088] If the number of the new population exceeds the set population size, it is sorted according to the fitness value and the individuals with the highest fitness are selected to form a new population.

[0089] 1.5.7, Iterative Evolution:

[0090] The process of selection, crossover, mutation and generation of new populations is repeated until the termination condition is met (such as reaching the maximum number of iterations, the fitness value reaches a preset threshold, or the change in the solution is less than a preset threshold, etc.).

[0091] 1.5.8. Output the best solution:

[0092] After the evolution process is over, the individual with the highest fitness is selected from the final population as the best solution. The shoe geometry model represented by this individual is the optimal design searched by the genetic algorithm.

[0093] Genetic algorithms can be used to efficiently search for optimal solutions in complex shoe design spaces. This approach can not only handle a large number of design parameters and constraints, but also discover novel and practical design solutions by simulating the biological evolution process.

[0094] 1.6. Using optimization algorithms (genetic algorithms) that simulate the principles of natural selection and genetics, we can find the best solution by simulating the biological evolution process and generate the best complex shoe geometry model;

[0095] Second, according to the mechanical requirements of the shoe, under the given design space, boundary conditions and load conditions, the complex shoe geometric model with the best structural performance is obtained by optimizing the material distribution; the goal is to find the optimal layout of material distribution so that the structure has the best combination of maximum stiffness, minimum weight or other performance indicators while meeting specific functions and constraints, ensuring the optimal distribution of the internal structure. The specific methods are as follows:

[0096] 2.1 Verification Experiment

[0097] Assumptions:

[0098] The sole area of ​​the shoe is A = 250 cm 2 (25000mm 2 );

[0099] The total load on the shoe is F = 800N (about 80kg body weight);

[0100] The thickness of the shoe is h = 10 mm;

[0101] The width of the shoe is b = 90 mm;

[0102] The length of the shoe is l = 300 mm;

[0103] Young's modulus of the material E = 200 Gpa;

[0104] The yield strength of the material is σy = 300Mpa;

[0105] but:

[0106] According to the Cauchy stress formula: σ=F / A=800 / 25000=0.032Mpa;

[0107] Assume that the bending moment M on the shoe is generated by the load applied to the middle of the shoe:

[0108] M=F*l / 4=800*300 / 4=60000Nmm;

[0109] I=b*h 3 / 12=90*10 3 / 12=90*1000 / 12=7500mm 4 ;

[0110] c = h / 2 = 10 / 2 = 5 mm;

[0111] Calculate σbend, σbend = M*c / I = 60000*5 / 7500 = 40Mpa;

[0112] σ total=σ+σ bend=0.032+40=40.032Mpa;

[0113] σtotal≤σy(300Mpa);

[0114] Under the same load, the total stress σtotal of the 3D printed shoes and the total stress of the physical shoes (the physical shoes were printed and the stress of the physical shoes was detected to be 40.032Mpa) are the same, and both are lower than the yield strength σy of the material; therefore, the yield strength of the 3D printed shoes and the physical shoes are equivalent.

[0115] 2.2. Optimize the mechanical properties and aesthetics of the shoe by adjusting the parameters of the TPMS (three-periodic minimum surface) lattice structure model (such as period, amplitude, phase, etc.);

[0116] 2.3. Design lattice structures of different densities and shapes in different areas according to the user's functional requirements for shoes;

[0117] Preferably, the design software Grasshopper is used to perform parametric design of the lattice structure to accurately control the size, shape and distribution of the lattice;

[0118] 3. Slice Processing

[0119] 3.1. Use Materialise Magics, Netfabb or other slicing software to perform high-precision slicing on complex shoe geometry models to ensure printing accuracy;

[0120] 3.2. Select a slice thickness of 5-20 microns to improve printing resolution and detail performance;

[0121] 3.3. Adopt intelligent support generation algorithm, drawing on the literature "Establishment and discussion of comparative experiments in artificial intelligence algorithms - taking genetic algorithm as an example", to optimize the support structure for subsequent removal and reduce material waste;

[0122] 3.4. Automatically adjust slice thickness according to geometric shape and complexity to balance printing speed and quality;

[0123] 3.5. Use different slicing strategies for different areas of the shoe, such as the sole area. The sole is the part of the shoe that bears the most pressure and needs to have high wear resistance, skid resistance and stability. At the same time, the design of the sole often contains complex textures and concave-convex structures.

[0124] Take the sole as an example, the same applies to other parts of the shoe:

[0125] Slicing strategy:

[0126] Layer thickness selection: Since the sole part has a relatively simple structure and does not require extremely high precision (compared to the upper), a larger layer thickness can be used for slicing to improve printing efficiency and material utilization.

[0127] Support structures: Additional support structures may need to be added to the bottom of the sole to ensure stability during printing, especially when printing soles with overhanging structures. Support structures should be designed to be easily removed and not affect the appearance and function of the final product.

[0128] Filling pattern: To increase the strength and stability of the sole, a honeycomb or other efficient filling pattern can be used to provide adequate support while maintaining lightweight.

[0129] Ensure the best printing effect in every area.

[0130] 4. 3D printing:

[0131] 4.1. Use high-precision 3D printing equipment such as SLM (selective laser melting), EBM (electron beam melting) or Multi-Jet Fusion for printing to ensure the details and quality of the shoes;

[0132] 4.2. Dynamically adjust the laser power and scanning speed according to the functional requirements of different areas of the shoes to ensure the uniformity and density of printing;

[0133] 4.3. Real-time monitoring and adjustment of the temperature during printing (approximately 210-240°C) to reduce thermal stress and deformation;

[0134] 4.4. Add nano-scale additives (such as a combination of one or more of carbon nanotubes and graphene) to the printed substrate to enhance the strength, toughness and conductivity of the material. The nano-scale additives account for 8-15% of the total printed material mass.

[0135] 5. Use a dual curing mechanism to bond decorations to shoes

[0136] 5.1. Use dual-curing resin to form the basic structure of the shoe after light curing, while retaining some uncured components to increase the flexibility of the subsequent bonding process;

[0137] 5.2. Apply uncured dual-curing resin between the shoe body and the decoration to be inlaid, and perform preliminary light-curing bonding by irradiation;

[0138] 5.3. Post-curing the entire shoe to ensure that all adhesive surfaces are firmly bonded and the mechanical properties are improved;

[0139] 6. Post-processing

[0140] 6.1. Use automated support removal equipment to remove the support, ensuring that the surface of the shoe is not damaged;

[0141] 6.2. Use high-energy laser beams to etch and cut the surface of the shoes, and engrave personalized patterns and texts on the surface or inside of the shoes.

[0142] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing 3D printed shoes, characterized in that it comprises the following steps:

1. Digital Modeling 1.

1. Generate TPMS lattice structure model; 1.

2. Use deep learning technology to extract features and train models for design data, and establish a mapping relationship between complex geometric shapes and design parameters; 1.

3. Input the user's parameters, generate a preliminary shoe model, and optimize the structural details through adaptive adjustment; 1.

4. The user can adjust and optimize the preliminary model in real time through the interactive design platform to obtain a complex shoe geometry model that meets the requirements; 1.

5. Using optimization algorithms that simulate natural selection and genetics, we simulate the biological evolution process to find the best solution and generate the best complex shoe geometry model; 1.

6. Generate the best complex shoe geometry model using genetic algorithm; Second, according to the mechanical requirements of the shoe, under the given design space, boundary conditions and load conditions, the complex shoe geometric model with the best structural performance is obtained by optimizing the material distribution; the specific method is as follows: 2.

1. Optimize the mechanical properties and aesthetics of the shoes by adjusting the parameters of the TPMS lattice structure model; 2.

2. Design lattice structures of different densities and shapes in different areas according to the functional requirements of the shoes; 3. Slice Processing 4. 3D printing; 5. Use a dual curing mechanism to bond decorations to shoes.

2. The method for preparing 3D printed shoes according to claim 1, characterized in that: Step three is as follows: Use slicing software to perform high-precision slicing on complex shoe geometry models; select a slicing layer thickness of 5-20 microns; use an intelligent support generation algorithm to optimize the support structure; and use different slicing strategies for different areas of the shoe.

3. The method for preparing 3D printed shoes according to claim 2, characterized in that: Step four specifically includes: using 3D printing equipment for printing; dynamically adjusting the laser power and scanning speed according to the functional requirements of different areas of the shoe; real-time monitoring and adjusting the temperature during the printing process; and adding nano-scale additives to the printing substrate.

4. The method for preparing 3D printed shoes according to claim 3, characterized in that: The nanoscale additive is a combination of one or more of carbon nanotubes and graphene.

5. The method for preparing 3D printed shoes according to claim 4, characterized in that: Nanoscale additives account for 8-15% of the total printing material mass.

6. The method for preparing 3D printed shoes according to claim 5, characterized in that: Step 5 specifically includes the following steps: 5.

1. Use dual-cure resin to form the basic structure of the shoe after light curing, while retaining some uncured components; 5.

2. Apply uncured dual-curing resin between the shoe body and the decoration to be inlaid, and perform preliminary light-curing bonding by irradiation; 5.

3. Post-curing the entire shoe to ensure that all adhesive surfaces are firmly bonded.

7. The method for preparing 3D printed shoes according to claim 6, characterized in that: Also includes post-processing steps.

8. The method for preparing 3D printed shoes according to claim 7, characterized in that: Post-processing The following steps are involved: 6.

1. Use automated support removal equipment to remove the support, ensuring that the surface of the shoe is not damaged; 6.

2. Use high-energy laser beams to etch and cut the surface of the shoes, and engrave personalized patterns and texts on the surface or inside of the shoes.

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