Customized three-dimensional structure rapid manufacturing method and system based on thermal shrinkage material and crocheting technology

Abstract

The invention discloses a customized three-dimensional structure rapid manufacturing method and system based on a heat shrinkage material and a crocheting technology, and the method comprises the following steps: 1), designing and generating a bottom plate based on a computer-aided system, generating a preset crocheting path, carrying out the parameter optimization adjustment according to a previewed deformation effect, and determining the crocheting path; 2) cutting the thermal shrinkage material according to the generated bottom plate structure to obtain a bottom plate, and finishing knitting on the bottom plate by adopting a chain stitch method according to the crocheting path; and (3) heating the woven fabric and bottom plate integrated structure, and controlling the shape of the fabric and bottom plate integrated structure by virtue of a thermal shrinkage effect. According to the method, a computer aided design tool is combined with a basic crocheting stitch method, the technical threshold of manual knitting and modeling design of a manufacturer is remarkably reduced, that is, conversion from a two-dimensional fabric to a three-dimensional form can be efficiently achieved through simple heating operation, and the form customizability and design flexibility of a three-dimensional crocheting work are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the interdisciplinary technical field of digital manufacturing and textile technology, and relates to a three-dimensional structure forming method that integrates traditional crocheting technology with digital manufacturing, and in particular to a method and system for rapid production of customized three-dimensional structures based on heat shrinkable materials and crocheting technology. Background Art

[0002] Crochet, as a traditional hand-woven textile craft, is popular for its unique texture expression and complex three-dimensional shapes. However, traditional crochet methods still have the following shortcomings:

[0003] 1. Reproducibility: The traditional crocheting process relies heavily on the maker's experience and skill. Variations in stitch strength and inconsistencies in stitch technique often lead to discrepancies between the finished product and the intended design. Furthermore, learning multiple complex stitches, calculating and flexibly combining stitches, and other complex techniques place high demands on the crocheter, hindering production efficiency and making it difficult to reproduce designs or produce standardized crocheted products.

[0004] 2. Innovative Design: The control of complex shapes in crochet works places high demands on the maker's craftsmanship and ability to grasp spatial form. For non-professional enthusiasts, quickly learning or independently designing and producing complex three-dimensional crochet works is challenging, thus limiting the diversity and innovation of fabric design.

[0005] To address the above issues, the present invention proposes a method for rapidly fabricating customized three-dimensional structures based on heat-shrinkable materials and crochet technology. By utilizing the physical properties of heat-shrinkable materials and combining them with computer-aided design (CAD), the maker can directly transform a flat fabric into the desired three-dimensional form through heating. This method significantly simplifies the stitching and craftsmanship required for crochet production, enabling beginners to easily create complex three-dimensional crochet pieces. Furthermore, the accompanying software tools provide design assistance and morphology simulation capabilities, further enhancing the personalization and interest of the designs. This method not only lowers the technical threshold for crochet creation but also provides a convenient and efficient way for users to explore personalized designs, opening up new possibilities for the art of crochet. Summary of the Invention

[0006] This invention aims to address the high manual skill required to create complex three-dimensional shapes in existing crochet techniques. It provides a method and system for rapidly creating customized three-dimensional structures using heat-shrinkable materials and crochet technology. Specifically, this method draws inspiration from the fundamental stitches of two traditional crafts, embroidery and crocheting, cleverly integrating the creative concepts of embroidery with the tools and materials of crocheting. In traditional embroidery, stitches are layered onto fabric to create flat or bas-relief decorative effects. In contrast, the innovative technology proposed by this invention transforms the base material from merely a flat carrier for the pattern to a medium for constructing three-dimensional structures. Users apply crochet techniques (particularly a single embroidery stitch, the chain stitch) onto heat-shrinkable film, connecting each stitch to the previous one to form a chain-like pattern. This method creatively utilizes the deformation properties of heat-shrinkable film upon heating, allowing the originally two-dimensional fabric to automatically transform into a predetermined three-dimensional form. This method not only imparts the unique texture and three-dimensional appearance of crocheted products but also revolutionizes the traditional artisanal approach to creating three-dimensional textile structures, achieving a transition from two-dimensional to three-dimensional. Users can create unique three-dimensional textiles without complex production techniques or extensive experience. To enhance practicality, this method also provides a complete shape deformation library (hereinafter referred to as the "deformation library") and user-friendly software tools, covering the entire process from design to manufacturing, with high flexibility and customization capabilities.

[0007] The technical solution adopted by the present invention comprises the following steps:

[0008] A method for rapidly producing a customized three-dimensional structure based on heat shrinkable materials and crochet technology, the method comprising the following steps:

[0009] 1) Generate a base plate based on computer-aided system design and generate a preset crochet path, optimize and adjust parameters based on the previewed deformation effect, and determine the crochet path;

[0010] 2) cutting the heat shrinkable material according to the generated bottom plate structure to obtain a bottom plate, and knitting the bottom plate using a crochet technique according to the crochet path;

[0011] 3) The woven fabric base plate integrated structure is subjected to a heat treatment, and the shape of the fabric base plate integrated structure is controlled by means of a heat shrinkage effect.

[0012] Furthermore, the step 1) specifically includes:

[0013] Determine the shape of the base plate in a computer-aided system, design and form a number of holes on the base plate for subsequent crocheting, and control the distribution of the holes by adjusting the size and spacing of the holes;

[0014] A simulation module is provided in the computer-aided system for simulating and displaying the deformation effect of the base plate after the thermal shrinkage effect of the base plate under a preset crocheting path according to the layout of the base plate and the holes thereon, and the type of thermal shrinkage material corresponding to the selected base plate.

[0015] Furthermore, the design method of the simulation module includes the following:

[0016] (1) Experimental measurement: Select heat-shrinkable materials and crochet wires, and design and prepare flat knitted specimens with different knitting densities, stitch types, and wire tensions. For each set of specimens, a constant temperature heating experiment is performed, with multiple temperature levels and different heating times set. The deformation parameters of the specimens, including length shrinkage, area shrinkage, local thickness change, and deformation curvature, are recorded in real time to form a multivariate heat shrinkage response dataset.

[0017] (2) Data fitting: The experimental data in the thermal shrinkage response data set are cleaned and statistically processed to remove outliers. The average value of multiple sets of data under the same working conditions is taken to reduce experimental errors. The relationship between each deformation parameter and temperature, time, braiding density and wire tension factors is fitted using a machine learning method to obtain a continuous prediction model describing the shrinkage behavior to express the trend and amplitude of the deformation of the braided structure driven by the thermal shrinkage material under different process parameters.

[0018] (3) Simulation verification: The fitted model is embedded into the simulation solution software in the form of a function or equation, and the geometric constraints and wire connection conditions are combined to jointly construct a physical simulation framework for thermal deformation. During the simulation process, the solver solves the dynamic position evolution of the braided particles under the thermal shrinkage constraint in real time and outputs the three-dimensional morphological changes caused by shrinkage. By comparing the three-dimensional morphology output by the simulation with the actual morphology after heat treatment, the accuracy of the model is verified and the error is corrected until the deviation between the simulation prediction value and the experimental result is within an acceptable range.

[0019] Furthermore, the simulation module is based on the Kangaroo solver as the simulation core, and describes the geometric or mechanical requirements that the entire system needs to meet by establishing targets containing multiple physical constraints. The targets include: targets for fixing the position of a specified particle at a preset coordinate, targets for constraining or adjusting the length of a line segment, and targets for applying a directional external force to the particle; each target is defined as a corresponding potential energy function. When the target state reaches the expected value, the energy is minimized or zero. The solver uses the particle as the basic calculation unit, explicitly integrates the motion state of the particle in continuous time, and iteratively updates the position and velocity of the particle until the system kinetic energy is less than the set threshold and reaches an overall equilibrium state; the simulation module automatically generates a discretized grid that matches the size of the base plate based on the spatial arrangement of the base plate and the holes, and inputs the grid nodes as particles into the solver to achieve real-time morphological evolution and adaptive optimization of the base plate and the hole structure thereon under external forces and geometric constraints.

[0020] Furthermore, the heat shrinkable material is a copolyolefin heat shrinkable film, and the crocheting technology is to use the chain stitch method in the embroidery process for crocheting.

[0021] Furthermore, the heating treatment uses a hot air gun, a hair dryer or a hot air blower to make the surface temperature of the fabric base plate integrated structure reach the deformation driving temperature of the heat shrinkable material.

[0022] Furthermore, after chain stitching, the heat shrinkage drives the fabric base plate integrated structure to deform based on the following two basic deformation modes:

[0023] Bending deformation: When the holes are evenly distributed, the chain stitch method makes the wire arrangement density on the front and back of the base plate different, with the front being dense and the back being loose. The heat shrinkage drives the integrated structure of the fabric base plate to bend towards the back.

[0024] Folding deformation: If the spacing between two columns in the hole array is within a preset spacing range and the spacing between other columns is larger than the preset spacing range, the heat shrinkage-driven fabric base plate integrated structure will show a folding effect by bending along the two columns of holes.

[0025] Furthermore, the computer-aided system is also provided with a deformation library consisting of several base plate styles. The shapes, hole distributions, and crochet paths of these base plate styles are all known, and the deformation effects after heat shrinkage occurs under the selected heat shrinkage material are also known. Users can directly select a specific base plate style to achieve the desired deformation effect.

[0026] Furthermore, the deformation library includes:

[0027] The geometry sub-library: After deformation, its base plate style is a basic geometric shape, including at least a cylinder, a frustum, and a hemisphere. The base plate style of the cylinder is a square base plate with evenly distributed holes, and a crochet path is filled in a filling manner. The base plate style of the frustum is a circular base plate with evenly distributed holes radially, and the crochet plane is filled in a continuous "J" pattern. The base plate style of the hemisphere is a circular base plate with evenly distributed holes in a combination of radial and spiral patterns. The radial holes are filled in a filling manner, and the spiral holes are crocheted in a spiral pattern.

[0028] Folding sub-library: After the base plate style is deformed, the folding forms include at least single folding and triangular folding. The single folding base plate style has holes unevenly distributed on the square base plate, the spacing between two columns is smaller than the spacing between other columns, and an S-shaped crocheting path is used. The triangular folding base plate style has holes unevenly distributed on the triangular base plate, the spacing between the holes on the line connecting the triangle vertices to the center is smaller than the spacing between other columns, the portion with larger spacing holes uses a filling crocheting path on the front side, and the portion with smaller spacing holes uses a filling crocheting path on the back side.

[0029] Wave sub-library: The deformed shape of its base plate style includes at least curling, large waves, and skirts. The curled base plate style is to evenly distribute holes on the rectangular base plate, and adopt a filling-type crocheting path along the inclination of 45 degrees to 60 degrees to the long side. The large wave base plate style is to evenly distribute holes on the circular base plate, and adopt a spiral crocheting path; the base plate style of the skirt is that the holes are radially evenly distributed on a complete or incomplete circle. When crocheting, it is necessary to constantly alternate between the front and back sides, and adopt a filling-type crocheting path.

[0030] Concave-convex sub-base: After deformation, the base plate has at least concave-convex shapes inside and outside. The base plate has holes evenly distributed on the elliptical base plate. The middle elliptical part adopts a spiral crocheted path on the front side, and the outer elliptical part adopts a spiral crocheted path on the back side.

[0031] Hollow sub-library: After the base plate is deformed, it includes at least middle hollowing and spanning hollowing. The middle hollowing base plate style is to cut off part of the base plate in the part that needs to be hollowed out, and the holes are evenly distributed in the remaining part, using a filling-type crocheting path. The spanning hollowing base plate style is to not cut holes in the part that needs to be hollowed out, and the holes are evenly distributed in the remaining part, using a filling-type crocheting path.

[0032] Furry sub-library: Its base plate style is a circular base plate with evenly distributed holes. The diameter of the holes is set smaller than the minimum hole diameter Dmin = 0.56d + 1.02mm, where d is the actual thickness of the braided wire, and a spiral crocheted path is used.

[0033] The present invention also provides a system for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology, comprising:

[0034] The deformation library adjustment module integrates a variety of baseboard styles and patterns with known deformation effects for users to choose and fine-tune parameters;

[0035] The personalized customization module allows users to input custom edge tracks to design the base plate shape, design the hole distribution on the base plate by hole size and spacing, and select different path combinations to form preset crochet tracks to achieve personalized base plate design;

[0036] The simulation module is used to display the completed base plate and preset crochet trajectory, and at the same time display the predicted deformation effect in real time to facilitate user adjustment and optimization;

[0037] The pattern output module is used to output the base plate design that determines the crocheting path and generate a target model output for subsequent cutting processing and knitting according to the crocheting path.

[0038] The beneficial effects of the present invention are:

[0039] The method and system of the present invention are applicable to various types of fabric threads. Users can weave threads along specific paths on heat-shrinkable material and create complex fabric shapes through heating. The entire process does not require specialized materials, customized cutting equipment, or additional processing and manufacturing processes, offering the advantages of low manual effort and highly customizable shapes. Fabrics produced using this method have a wide range of applications, including daily necessities, installation art, clothing design, electronic fabric design, and interactive fabric design. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of a method for rapidly producing a customized three-dimensional structure according to an embodiment of the present invention;

[0041] Figure 2 A schematic diagram of a base plate designed by a computer-aided system based on a deformation library in an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a base plate designed using a computer-aided system in a custom mode according to an embodiment of the present invention;

[0043] Figure 4 Schematic diagram of deformation basic unit and deformation library of computer-aided system in an embodiment of the present invention;

[0044] Figure 5 This is a schematic diagram of the chain stitch method;

[0045] Figure 6Schematic diagram of the experimental process and fitting results for simulating specific parameters in deformation in an embodiment of the present invention; the figure is a study of the hole size and hole spacing range suitable for wires of different thicknesses: (a) parameter diagram,

[0046] (b) The fit between the thickness of different types of wire (Lace-0.6mm, Super fine-1.2mm, Fine-1.65mm, Medium-3.0mm, Bulky-5.36mm) and the hole diameter (the fit is too tight, appropriate, and too loose, respectively); (c) The bending angles of different wire thicknesses (0.6, 1.65, 3.0, 5.36 / mm) at different numbers of rows; (d) The bending angles of different wire types (Lace, Fine, Medium) at different spacings; (e) The bending angles of different wire thicknesses (0.6, 1.2, 1.65, 3.0, 5.36 / mm) at various numbers of rows are consistent.

[0047] Figure 7 Schematic diagram of post-processing techniques in an embodiment of the present invention;

[0048] Figure 8 This is a specific example of a fashion design based on the method of the present invention: a design with rich shapes and textures. (a1) Baseboard shape and knitting path, (a2) Fabric before heating, (a3) ​​Fabric folded after heating, (b) Scarf made using the folding library, showcasing a variety of shapes and wearable styles.

[0049] Figure 9 Another specific embodiment of the method of the present invention: a complex curved art installation. (a1) Baseboard shape and weaving path, (a2) Fabric before heating, using a thread-changing technique to weave different colors, (a3) ​​Fabric after heating, forming a wavy curve, and (b) Assembling modular units to create the art installation.

[0050] Figure 10 Another specific embodiment of the method of the present invention is a spherical lampshade assembled from a modular deformation library. (a1) Base plate shape and weaving path, (a2) Fabric before heating, (a3) ​​Fabric formed into a hyperboloid shape after heating, (a4) Sewing two base units, and (b) Assembling the modular units to produce a spherical lampshade.

[0051] Figure 11 Another specific embodiment of the method of the present invention: a children's picture book with 4D interactive functionality. (a1, a4) Baseboard shape and weaving path; (a2, a3, a5, a6) Close-ups of the fabric deformation before and after heating; (b) Comparison of the children's picture book before and after heating conditions are triggered.

[0052] Figure 12 Another specific embodiment of the present invention is a customizable smart cushion that adjusts lighting based on the user's sitting posture. (a) The base plate shape and circuit layout. (b) The user's leaning back stretches the conductive yarn, causing a change in resistance. The smart cushion detects this behavior and controls the lighting. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific examples.

[0054] According to a specific embodiment of the present invention, a method for quickly making a customized three-dimensional structure based on heat shrinkable materials and crochet technology includes the following steps (see Figure 1 ):

[0055] S1 computer-aided design baseplate. Using computer-aided design software, a detailed 2D baseplate path diagram is created, and the software's simulation function is used to preview the deformation effect and weaving path. Once the design is complete, the user needs to export the design to DXF format (or SVG format) for cutting.

[0056] S2: Baseboard cutting. Select a suitable heat-shrinkable material as the baseboard material, such as POF film or organza. Use digital manufacturing methods (such as laser cutting) to process this material into the baseboard.

[0057] S3 weaves along the base plate. The weaving process follows a pre-set pattern, passing the wires through the holes in the film base plate along the designed weaving path to form a multi-layer composite fabric structure.

[0058] S4 heats the fabric. The composite fabric structure is treated by heating so that the heat shrinkable layer shrinks, thereby controlling the deformation of the fabric and forming a desired three-dimensional shape.

[0059] S5 Fabric Post-Processing. After the fabric is heated and reaches the desired shape, it is allowed to cool at room temperature. Alternatively, further post-processing operations such as stitching and cutting can be performed as needed to further enhance the fabric's shape. Ultimately, the desired complex fabric shape is achieved.

[0060] According to a specific embodiment of the present invention, Figure 2 、 Figure 3The computer-aided system designed in S1 is shown. In this computer-aided system, the user determines the shape of a base plate and designs a number of holes on the base plate for subsequent crocheting. The hole distribution is controlled by adjusting the hole size and spacing. The computer-aided system includes a simulation module for simulating and displaying the deformation effect of the base plate after the base plate heat shrinks under a preset crocheting path based on the layout of the base plate and its holes, as well as the type of heat shrinkable material selected for the base plate. The computer-aided system pre-provides a deformation library containing base plate styles with known target shaping effects. These base plate styles have known shapes, hole distributions, and crocheting paths. The user can directly select a specific base plate style to achieve the desired deformation effect.

[0061] The user can perform any of the following operations through the computer-assisted system:

[0062] 1. Select the type in the deformation library: users can create fabric shapes with rich geometric shapes and textures by pre-designing the base plate path. According to a specific embodiment of the present invention, the system has built-in five types of deformation sub-libraries for users to refer to and select. In the deformation library selection interface, there is a schematic diagram of the deformation effect under each deformation unit category. Users only need to click on the required deformation unit to see the preset base plate design and related parameters in the interface. The five types of deformation sub-libraries are: geometric, folded, wavy, concave and convex, hollow and fur. Each deformation sub-library also contains multiple deformation units (such as Figure 4 ):

[0063] Geometric sub-library: its base plate style is a basic geometric shape after deformation, including at least a cylinder, a frustum, and a hemisphere. In addition, there can also be some complex hyperbolic shapes. Among them, the base plate style of the cylinder is to evenly distribute holes on the square base plate, and adopt a crochet path of filling method. To fill these holes, it is necessary to crochet continuously row by row or column by column according to the arrangement of the holes. The base plate style of the frustum is to evenly distribute holes radially on the annular base plate, and adopt a continuous "J"-shaped method to fill the crochet plane path. The base plate style of the hemisphere is to evenly distribute holes radially and spirally on the circular base plate, and adopt the holes of the radial part to fill the path and the holes of the spiral part to crochet the path in a spiral shape. Figure 4 In the example, the geometry library displays the following: frustum, hemisphere, cone, hyperboloid 1, hyperboloid 2, donut, and cylinder.

[0064] Folding sub-library: The folding form after the base plate style is deformed includes at least single folding and triangular folding, wherein the base plate style of the single folding is unevenly distributed holes on the square base plate, the spacing between two columns is smaller than the spacing between other columns, and an S-shaped crocheting path is adopted; the base plate style of the triangular folding is unevenly distributed holes on the triangular base plate, the spacing between the holes on the line connecting the triangle vertex to the center is smaller than the spacing between other columns, the part with larger spacing holes adopts a filling crocheting path on the front side, and the part with smaller spacing holes adopts a filling crocheting path on the back side; Figure 4 In the example, single folding, triangular folding and multi-mode folding formed by combining these two methods are shown in sequence.

[0065] Wave sub-library: The deformed forms of its base plate include at least curling, large waves, and skirts. The curled base plate style is to evenly distribute holes on the rectangular base plate, and adopt a filling-type crocheting path along the 45-60 degree inclination to the long side. The large wave base plate style is to evenly distribute holes on the circular base plate, and adopt a spiral crocheting path. The skirt base plate style is to evenly distribute holes radially on a complete or incomplete circle, and alternately adopt a filling-type crocheting path on the front and back. Figure 4 In the example, curls, big waves, hems, and big waves in both directions are shown in order.

[0066] Concave-convex sub-base: The deformed form of the base plate includes at least one concave-convex texture design. The base plate style is an elliptical base plate with evenly distributed holes. The middle elliptical part adopts a spiral crocheted path on the front, and the outer elliptical part adopts a spiral crocheted path on the back. Figure 4 As shown in .

[0067] Hollowing sub-library: Contains two hollowing design methods: one is to plan the internal hollowing in advance during the base plate design stage, that is, the middle hollowing; the other is to skip part of the base plate during the knitting process to form a hollowing effect, that is, the cross-hollowing. The base plate style of the middle hollowing is to cut off part of the base plate in the part that needs to be hollowed, and the holes are evenly distributed in the rest of the part, using a filling-type crocheting path. The base plate style of the cross-hollowing is to not cut holes in the part that needs to be hollowed, and the holes are evenly distributed in the rest of the part, using a filling-type crocheting path. Figure 4 In the example, the middle hollowing and the spanning hollowing are shown in sequence.

[0068] The Fuzzy Sub-Library is a fabric that weaves coils over the holes in the base plate. After heating, the base plate is tightened to secure the wire, creating a fuzzy texture. Alternatively, the coils can be cut to create a different kind of fuzzy texture. By controlling the size of the coils, the user can adjust the length of the fuzz. The base plate features evenly distributed holes on a circular shape, with a hole diameter set to less than the minimum hole diameter (Dmin = 0.56d + 1.02mm), where d is the actual thickness of the braided wire. A spiral weaving path is used. Figure 4 The examples show the fuzz formed by the coil and the fuzz formed after the coil is cut.

[0069] 2. Customizable Deformation Unit Parameters: Each deformation unit can be customized to achieve different deformation effects. For example, in the "Donut" deformation unit, the relevant parameters include the inner and outer radius of the ring base, the number of concentric circles, the hole spacing, and the hole radius. Users can adjust these parameters by dragging sliders on the interface and view the updated base effect in real time. The hole size and hole spacing suitable for wires of different thicknesses can be determined through experimental testing.

[0070] 3. Custom Plate Design: Users can select desired points and multiple plates by clicking the "Select Points" and "Select Plates" buttons, respectively. The system will automatically calculate and remove overly close points, merging them into a single plate. Additionally, users can import custom curves. Click the "Select Points" and "Select Outline" buttons to select the desired points and the curve, respectively. The system will automatically remove points outside the curve and use the curve as the plate's outer contour. This feature provides users with a greater degree of freedom in plate design, helping them achieve better creative results.

[0071] 4. Preview the baseplate and simulated deformation effects: Simply toggle the simulation interface on to preview the current baseplate after knitting and heating. Users can also adjust parameters and click the "Refresh" button to update the simulation results. This feature allows users to quickly iterate baseplate designs until they achieve the desired result.

[0072] 5. Generate Curves and Cutting Files: After completing the design, click the "Generate" button to import the curves into Rhino and export the resulting file as a DXF file for laser cutting. Alternatively, click the "Path Display" button, and the system will automatically generate a path to guide the knitting sequence.

[0073] In the present invention, the core of building a computer-aided system is to implement the simulation module, which can simulate the shrinkage behavior of the heat-shrinkable material under a specific base plate structure and weaving path. In order to achieve the predictability of the morphological change of the material during the heat treatment process, the shrinkage behavior of the heat-shrinkable material needs to be experimentally measured, data fitting and simulation verification. Specifically, the following steps are included:

[0074] First, a heat-shrinkable material consistent with actual processing (typically a multilayer co-polyolefin heat-shrinkable film, or POF film, in this case) and a typical crochet yarn were selected to design and prepare flat knitted specimens with varying weave densities, stitch types, and yarn tensions. For each set of specimens, a constant-temperature heating experiment was performed, using multiple temperature settings (e.g., 60°C, 80°C, 100°C, and 120°C) and varying heating durations. Parameters such as the specimen's length shrinkage, area shrinkage, local thickness change, and deformation curvature were recorded in real time to generate a multivariate heat shrinkage response dataset.

[0075] Secondly, the collected experimental data are cleaned and statistically processed to remove outliers, and the average of multiple sets of data under the same working conditions is taken to reduce experimental errors. In view of the relationship between shrinkage rate and factors such as temperature, time, braiding density and wire tension, machine learning methods such as multivariate nonlinear regression, support vector machine regression or neural network are used to fit and obtain a continuous prediction model that describes the shrinkage behavior. This model can accurately express the trend and amplitude of the deformation of the braided structure driven by heat shrinkage materials under different process parameters. Figure 6 A specific experimental test and fitting process is shown in FIG.

[0076] The fitted model is then embedded into the simulation software as a function or equation. This paper preferably uses the Kangaroo solver in the Grasshopper platform as the simulation core, describing the aforementioned thermal shrinkage behavior as one of the input conditions for a custom Goal. This, combined with the geometric constraints of the chain stitch and the wire connection conditions, creates a physical simulation framework for thermally induced deformation. During the simulation, the solver calculates the dynamic positional evolution of the knitted particles under thermal shrinkage constraints in real time, outputting the three-dimensional morphological changes caused by the shrinkage.

[0077] Finally, by comparing the simulated 3D shape with the actual shape after heat treatment, the model's accuracy is verified and errors are corrected until the deviation between the simulation predictions and the experimental results is within an acceptable range. This simulation method allows users to quickly preview the corresponding shrinkage shapes for different baseboard patterns and weaving parameters during the baseboard design phase, significantly improving the controllability of 3D structure design and the success rate of one-shot molding.

[0078] According to a specific embodiment of the present invention, based on the Rhinoceros 7 design environment, Grasshopper (Rhinoceros's visual programming language) and Human UI (a Grasshopper plug-in) are used to implement a visual interactive interface. The Kangaroo solver (a Grasshopper plug-in) is used for simulation and baseplate optimization. The solver defines different energy forms that are zero under specific geometric conditions by establishing various goals (Goals) containing multiple physical constraints. Each goal is defined as a corresponding potential energy function. When the target state reaches the desired value, the energy is minimized or zero. The solver performs simulation by moving points to minimize the total energy experienced by all points in the system. The system defines multiple energy types as input for the solver, such as Anchor goals for fixed points, Length (Line) goals for line segment contraction, and Load goals for simulating Z-axis forces. Simulations are synchronized in real time with user adjustments to baseplate parameters: the mesh size used in the simulation matches the baseplate size, and the Strength parameter (Strength) of Length (Line) is proportional to the hole spacing. The system generates corresponding grids according to the layout of the base plate and holes, and performs deformation simulation through predefined targets. Specifically. The user inputs design parameters such as the outer contour size, internal hole layout, hole diameter and hole spacing of the base plate through the Human UI interface. The software automatically generates a model grid based on user input, and uses the Kangaroo Solver to iteratively update the discrete points in the simulation grid, calculates the force and velocity changes of the points in real time, and continuously adjusts the node position to minimize the total energy of the system. During the simulation process, the software directly binds the input base plate parameters (such as hole position, spacing, path curvature, etc.) to the generated cutting path through a data tree structure. If the user adjusts the parameters in the interface, the simulation grid and the cutting path will be updated synchronously to ensure that the morphological changes are consistent with the path geometry in real time.

[0079] In step S2, the method for making the base plate includes but is not limited to:

[0080] (1) Digital manufacturing using laser cutting. Output the DXF format file using a computer-aided system and set the cutting parameters in the LightBurn system. When using a 0.04mm thick POF film as the base material, the laser cutting machine is set to 12.5% ​​standard power and a cutting speed of 80mm / s is preferred. It is worth noting that excessive or insufficient laser cutting power will affect the cutting effect of the base. Excessive power will cause the heat shrink film to be burned and the holes to be deformed. Excessive power will cause the holes to be not cut in place, which will cause inconvenience in the weaving process on the base.

[0081] (2) Digital manufacturing using a low-cost paper cutter. Import the base plate file into the corresponding software and then place the material to be cut on the cutting table. When using this method, the SVG format file must be output using a computer-aided system and the cutting operation is completed in the Cricut Design Space system. This method can cut the target pattern more accurately, but the cutting efficiency is relatively low.

[0082] (3) Use a low-threshold punching tool to manually punch holes. You can choose two engraving knives and a punch for paper perforation purchased from an offline stationery store. Print the baseboard drawing using a home printer, then cover the baseboard material on the paper with the printed pattern. Use a cutting tool to cut the material and paper simultaneously along the pattern to obtain the baseboard material with holes.

[0083] In step S3, the crocheting technique involved in the embodiment of the present invention is mainly the chain stitch, which is a common and flexible embroidery stitch. Figure 5 As shown in the figure, its characteristic is that each stitch is connected to the previous stitch to form a chain-like stitch. In specific operation, the embroidery needle is passed through the back of the material to form a small loop, and then the needle is passed through the small loop again at the next stitch, and the thread is tightened to fix the stitch, and this is repeated to form a continuous chain effect. There are two strands of thread on the front of the base, and only one strand of thread on the back. This stitch method can create smooth lines and patterns on the fabric. The specific method of weaving follows the following four steps (see Figure 5 ): (1) Hold the crochet hook in your right hand and insert it into the hole to be hooked; (2) Use your left hand to guide the thread and wrap the thread around the crochet hook; (3) Pull out the crochet hook and pull the formed loop out of the hole; (4) Insert the crochet hook into the next hole. The user only needs to repeat this knitting step until all the holes are filled to complete the entire knitting process. If you need to switch between forward and reverse stitches, you can operate on the edge of the base plate: when the crochet hook stays on the loop of the last stitch on the front, flip the base plate and the crochet hook, adjust the needle insertion direction, so that the crochet hook enters from the hole of the first stitch on the back, and wrap the thread around the crochet hook, pulling out the loop while passing through the original loop on the crochet hook. This completes the switch between forward and reverse stitches, and you can continue to repeat the knitting steps.

[0084] In step S4, the fabric can be heated using a hot air gun, with different temperatures set depending on the selected base material. A multilayer co-polyolefin heat shrinkable film (POF film) with a thickness of 0.04 mm is used. The driving temperature of the film is about 65°C, and the shrinkage ratio can reach about 75%. When heating the POF film, it is more appropriate to set the temperature at 120-130 degrees Celsius. At this time, the temperature of the fabric surface is about 60 degrees Celsius, and the heat shrinkable film will show a significant shrinkage effect. It is worth noting that when the heating temperature exceeds 150 degrees Celsius, the middle layer will crack. For organza and nylon fabrics, it is recommended to set the hot air gun temperature at around 230 degrees Celsius, at which time the temperature of the fabric surface is about 90 degrees Celsius. When heating, it is preferred that the hot air gun be 5-10 cm away from the fabric, and the heat can be heated in a circular motion. Try to avoid concentrated heating of one place for a long time to prevent the middle layer material from cracking. In addition, the fabric can also be heat-treated using common heating devices in life such as hair dryers. Upon heating, the POF film shrinks, driving the wires together and deforming the fabric into the desired three-dimensional shape. The forming process relies primarily on two basic deformation units: (1) Bending: When the wires are properly spaced and evenly distributed, the wires will move closer together due to the shrinkage of the heat shrink film. Because the wires are arranged at different densities on the front and back of the fabric, the wires on the front are denser, resulting in less noticeable shrinkage; while the wires on the back are relatively sparse, they are significantly closer together under the action of the heat shrink film, giving the fabric a curved appearance. (2) Folding: If only appropriate spacing is maintained between certain columns, while the spacing between other columns is excessive, when the heat shrink film reaches its shrinkage limit, these excessive spacings will prevent the various fabric sections from fully approaching each other, preventing the desired bending effect. (For example, for lace threads, this spacing is typically between 2.4mm and 2.6mm, and the specific spacing can be determined experimentally based on the wire material). In this case, only the column with the appropriate spacing can bend, resulting in a folded effect overall. This differentiated shrinkage and convergence mechanism gives the fabric its unique three-dimensional shape.

[0085] The yarn involved in this example is crocheting yarn commonly used on the market, with the main components being 60% cotton and 40% acrylic. Its heat deformation temperature is about 150 degrees Celsius, and heating with a hot air gun will not have any adverse effects on it.

[0086] In the steps S3, S4 and S5, the weaving process and the fabric post-processing process can also use the manufacturing techniques to make the deformed fabric obtain a richer morphological effect (such as Figure 7 ), including two types of morphological control techniques and additional techniques:

[0087] Shape control skills are key skills in the process of making fabrics, which are divided into the following categories:

[0088] 1. Front-Back Combined Weaving: Weaving the front and back of a baseboard changes the distribution of the wires on both sides of the baseboard. This shift in the front and back of the wires influences the direction of the fabric's deformation after heating, achieving a predetermined geometric shape. This technique visually creates a richer sense of layering and texture.

[0089] 2. Heat the front and back sides separately: The side with denser threads is defined as the front. When the front side faces the heat source, the fabric contracts into a flat surface and no longer bends. When the back side faces the heat source, the fabric bends as intended. This technique allows deformable fabrics to function as flat sheets.

[0090] Additional techniques are optional and can be used to expand the design space during fabric production. They fall into the following categories: 1. Wire Switching: Utilizing the constraints imposed by the holes in the baseplate after heating and shrinking, wire switching can be accomplished based on the holes. This technique, by combining different wires, not only changes the appearance of the fabric but also creates unique textures.

[0091] 2. Pulling: Arrange wires at specific locations to locally pull the fabric into the desired shape. For example, a sphere can be broken down into multiple curved surfaces, with holes placed at the top. This allows the wires to pass through the holes and bring the surfaces together at a single vertex, ultimately forming a complete sphere. This technique offers the potential for more flexible interaction between the fabric and the user.

[0092] 3. Trimming: Under the constraints of the base plate, the fabric can be trimmed arbitrarily and continuously without causing the threads to become loose. This technique increases the flexibility of fabric modification.

[0093] 4. Post-production stitching: stitching multiple modular fabrics together to form complex surfaces. This technique can give the resulting fabric special properties, such as combining two identical surfaces to form a multi-stable fabric.

[0094] 5. Weaving Multiple Films Together: Combine and separate multiple layers of fabric. Design the same path in the desired merging areas, allowing the same strand of yarn to pass through the multiple layers, integrating them together. Wherever you wish to separate, weave each layer separately. This technique can create a richer form.

[0095] It is also possible to: (1) Process the wires during the weaving process: replace different types of wires during the weaving process to achieve a variety of visual effects; use a combination of front and back weaving methods to form a complex texture effect; combine multiple films to weave at the same time to achieve a complex three-dimensional shape. (2) Control during the heating process: During the heating process, the side with sparser wires can be selectively heated to achieve a sharp bending effect; heating the side with denser wires can produce a smoother finished product. (3) Fabric processing after heating: sew multiple pieces of fabric to form a complex large-volume fabric structure; pull the wires to create a more three-dimensional shape; trim the edges of the fabric to generate irregular curves and increase the expressiveness of the work.

[0096] In addition, the present invention also provides a system for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology. According to a specific embodiment of the present invention, the system includes:

[0097] The deformation library adjustment module integrates a variety of baseboard styles and patterns with known deformation effects for users to choose and fine-tune parameters;

[0098] The personalized customization module allows users to input custom edge tracks to design the base plate shape, design the hole distribution on the base plate by hole size and spacing, and select different path combinations to form preset crochet tracks to achieve personalized base plate design;

[0099] The simulation module is used to display the completed base plate and preset crochet trajectory, and at the same time display the predicted deformation effect in real time to facilitate user adjustment and optimization;

[0100] The pattern output module is used to output the base plate design that determines the crocheting path and generate a target model output for subsequent cutting processing and knitting according to the crocheting path.

[0101] like Figure 8 The figure shows a specific embodiment of the method of the present invention. This invention provides a rich variety of morphological possibilities for fashion design, imparting a certain stiffness to fabrics, enabling them to create more three-dimensional shapes. Textures such as concave, convex, and folded patterns also create unique organic forms for fashion design.

[0102] like Figure 9 、 Figure 10 The figure shows a specific embodiment of the method of the present invention. This invention also provides a more convenient way for people to create aesthetic objects in their daily lives. Users can assemble organic shapes such as waves and hyperboloids from the deformation library into aesthetically pleasing objects such as decorative paintings and spherical lampshades.

[0103] like Figure 11The figure shows a specific embodiment of the method of the present invention. The present invention integrates the deformed elements into the physical storybook, which can add more sensory elements to the narrative, give readers a stronger appeal, make the story vivid and have certain educational significance.

[0104] like Figure 12 The figure shows a specific embodiment of the method of the present invention. Using the support of a baseboard, the maker can pre-lay out circuits within the baseboard, thereby customizing everyday items with electronic functions. Part of this circuitry can be incorporated into the fabric. In the illustrated example, a cushion is used. When the user sits upright, the cushion is not pressed against, and the electronic fabric is in an unstretched state. However, when the user rests against the chair back, the electronic fabric woven into the cushion stretches, causing a change in resistance and, consequently, a change in the circuit output state.

[0105] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology, characterized in that: The method comprises the following steps: 1) Generate a base plate based on computer-aided system design and generate a preset crochet path, optimize and adjust parameters based on the previewed deformation effect, and determine the crochet path; 2) cutting the heat shrinkable material according to the generated bottom plate structure to obtain a bottom plate, and knitting the bottom plate using a crochet technique according to the crochet path; 3) The woven fabric base plate integrated structure is subjected to a heat treatment, and the shape of the fabric base plate integrated structure is controlled by means of a heat shrinkage effect.

2. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 1, characterized in that: The step 1) specifically includes: Determine the shape of the base plate in a computer-aided system, design and form a number of holes on the base plate for subsequent crocheting, and control the distribution of the holes by adjusting the size and spacing of the holes; A simulation module is provided in the computer-aided system for simulating and displaying the deformation effect of the base plate after the thermal shrinkage effect of the base plate under a preset crocheting path according to the layout of the base plate and the holes thereon, and the type of thermal shrinkage material corresponding to the selected base plate.

3. The method for rapidly producing a customized three-dimensional structure based on heat shrinkable materials and crochet technology according to claim 2, characterized in that: The design method of the simulation module includes the following steps: (1) Experimental measurement: Select heat-shrinkable materials and crochet wires, and design and prepare flat knitted specimens with different knitting densities, stitch types, and wire tensions. For each set of specimens, a constant temperature heating experiment is performed, with multiple temperature levels and different heating times set. The deformation parameters of the specimens, including length shrinkage, area shrinkage, local thickness change, and deformation curvature, are recorded in real time to form a multivariate heat shrinkage response dataset. (2) Data fitting: The experimental data in the thermal shrinkage response data set are cleaned and statistically processed to remove outliers. The average value of multiple sets of data under the same working conditions is taken to reduce experimental errors. The relationship between each deformation parameter and temperature, time, braiding density and wire tension factors is fitted using a machine learning method to obtain a continuous prediction model describing the shrinkage behavior to express the trend and amplitude of the deformation of the braided structure driven by the thermal shrinkage material under different process parameters. (3) Simulation verification: The fitted model is embedded into the simulation solution software in the form of a function or equation, and the geometric constraints and wire connection conditions are combined to jointly construct a physical simulation framework for thermal deformation. During the simulation process, the solver solves the dynamic position evolution of the braided particles under the thermal shrinkage constraint in real time and outputs the three-dimensional morphological changes caused by shrinkage. By comparing the three-dimensional morphology output by the simulation with the actual morphology after heat treatment, the accuracy of the model is verified and the error is corrected until the deviation between the simulation prediction value and the experimental result is within an acceptable range.

4. The method for rapidly producing a customized three-dimensional structure based on heat shrinkable materials and crochet technology according to claim 3, characterized in that: The simulation module is based on the Kangaroo solver as the simulation core. It describes the geometric or mechanical requirements that the entire system needs to meet by establishing targets containing multiple physical constraints. The targets include: targets for fixing the position of a specified particle at a preset coordinate, targets for constraining or adjusting the length of a line segment, and targets for applying a directional external force to the particle. Each target is defined as a corresponding potential energy function. When the target state reaches the expected value, the energy is minimized or zero. The solver uses the particle as the basic calculation unit, explicitly integrates the motion state of the particle in continuous time, and iteratively updates the position and velocity of the particle until the system kinetic energy is less than the set threshold and the overall equilibrium state is reached. The simulation module automatically generates a discretized grid that matches the size of the base plate based on the spatial arrangement of the base plate and the holes, and inputs the grid nodes as particles into the solver to achieve real-time morphological evolution and adaptive optimization of the base plate and the hole structure thereon under external forces and geometric constraints.

5. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 1, characterized in that: The heat shrinkable material is a copolyolefin heat shrinkable film, and the crocheting technology is to use the chain stitch method in the embroidery process for crocheting.

6. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 1, characterized in that: The heating treatment uses a hot air gun, a hair dryer or a hot air blower to make the surface temperature of the fabric base plate integrated structure reach the deformation driving temperature of the heat shrinkable material.

7. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 1, characterized in that: After chain stitching, the heat shrinkage-driven fabric base plate structure deforms in two basic modes: Bending deformation: When the holes are evenly distributed, the chain stitch method makes the wire arrangement density on the front and back of the base plate different, with the front being dense and the back being loose. The heat shrinkage drives the integrated structure of the fabric base plate to bend towards the back. Folding deformation: If the spacing between two columns in the hole array is within a preset spacing range and the spacing between other columns is larger than the preset spacing range, the heat shrinkage-driven fabric base plate integrated structure will show a folding effect by bending along the two columns of holes.

8. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 1, characterized in that: The computer-aided system also includes a deformation library consisting of several base plate styles. The shapes, hole distributions, and crochet paths of these base plate styles are all known, and the deformation effects after heat shrinkage occurs under the selected heat shrinkage material are also known. Users can directly select a specific base plate style to achieve the desired deformation effect.

9. The method for rapidly producing customized three-dimensional structures based on heat shrinkable materials and crochet technology according to claim 7, characterized in that: The deformation library includes: The geometry sub-library: After deformation, its base plate style is a basic geometric shape, including at least a cylinder, a frustum, and a hemisphere. The base plate style of the cylinder is a square base plate with evenly distributed holes, and a crochet path is filled in a filling manner. The base plate style of the frustum is a circular base plate with evenly distributed holes radially, and the crochet plane is filled in a continuous "J" pattern. The base plate style of the hemisphere is a circular base plate with evenly distributed holes in a combination of radial and spiral patterns. The radial holes are filled in a filling manner, and the spiral holes are crocheted in a spiral pattern. Folding sub-library: After the base plate style is deformed, the folding forms include at least single folding and triangular folding. The single folding base plate style has holes unevenly distributed on the square base plate, the spacing between two columns is smaller than the spacing between other columns, and an S-shaped crocheting path is used. The triangular folding base plate style has holes unevenly distributed on the triangular base plate, the spacing between the holes on the line connecting the triangle vertices to the center is smaller than the spacing between other columns, the portion with larger spacing holes uses a filling crocheting path on the front side, and the portion with smaller spacing holes uses a filling crocheting path on the back side. Wave sub-library: The deformed shape of its base plate style includes at least curling, large waves, and skirts. The curled base plate style is to evenly distribute holes on the rectangular base plate, and adopt a filling-type crocheting path along the inclination of 45 degrees to 60 degrees to the long side. The large wave base plate style is to evenly distribute holes on the circular base plate, and adopt a spiral crocheting path; the base plate style of the skirt is that the holes are radially evenly distributed on a complete or incomplete circle. When crocheting, it is necessary to constantly alternate between the front and back sides, and adopt a filling-type crocheting path. Concave-convex sub-base: After deformation, the base plate has at least concave-convex shapes inside and outside. The base plate has holes evenly distributed on the elliptical base plate. The middle elliptical part adopts a spiral crocheted path on the front side, and the outer elliptical part adopts a spiral crocheted path on the back side. Hollow sub-library: After the base plate is deformed, it includes at least middle hollowing and spanning hollowing. The middle hollowing base plate style is to cut off part of the base plate in the part that needs to be hollowed out, and the holes are evenly distributed in the remaining part, using a filling-type crocheting path. The spanning hollowing base plate style is to not cut holes in the part that needs to be hollowed out, and the holes are evenly distributed in the remaining part, using a filling-type crocheting path. Furry sub-library: Its base plate style is a circular base plate with evenly distributed holes. The diameter of the holes is set smaller than the minimum hole diameter Dmin = 0.56d + 1.02mm, where d is the actual thickness of the braided wire, and a spiral crocheted path is used.

10. A system for rapid production of customized three-dimensional structures based on heat shrinkable materials and crochet technology, characterized in that: include: The deformation library adjustment module integrates a variety of baseboard styles and patterns with known deformation effects for users to choose and fine-tune parameters; The personalized customization module allows users to input custom edge tracks to design the base plate shape, design the hole distribution on the base plate by hole size and spacing, and select different path combinations to form preset crochet tracks to achieve personalized base plate design; The simulation module is used to display the completed base plate and preset crochet trajectory, and at the same time display the predicted deformation effect in real time to facilitate user adjustment and optimization; The pattern output module is used to output the base plate design that determines the crocheting path and generate a target model output for subsequent cutting processing and knitting according to the crocheting path.

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