A manufacturing system and method for soft material multi-scale structures

Abstract

The application discloses a kind of manufacturing systems of soft material cross-scale structure, including extrusion deposition module, projection module, laser etching module, suspension medium container, rotating table, moving module, optical adjustment module and control system;The application is based on embedded extrusion printing, volume printing and laser etching technology to realize the cross-scale manufacturing of biological soft material, the manufacturing of macrostructure (sub-millimeter level) is realized by pre-deposition of multiple soft materials, one-time volume solidification, and the manufacturing of microstructure (micron level) is realized by fixed-point etching of soft material.

Description

Technical Field

[0001] This invention belongs to the field of biomanufacturing technology, and in particular relates to a manufacturing system and method for soft material multiscale structures. Background Technology

[0002] Bioprinting is a method for manufacturing biological functional structures by mixing native biological units such as cells and growth factors with biomaterials (such as hydrogels) and then customizing their arrangement with reference to biomimetic principles and the cellular microenvironment. When using bioprinting to construct biomimetic structures, it is necessary to simulate the macroscopic structures (branching blood vessels, intestinal folds, etc.) and microscopic structures (capillaries, intestinal villi, etc.) within the organism as closely as possible to fully replicate the cellular environment and improve the structural simulation accuracy. Currently, embedded extrusion bioprinting is one of the commonly used printing processes. The yield stress of the suspended medium during its manufacturing process can provide support for the structure, making this method suitable for bioprinting with low-stiffness bio-inks or unsupported structures. Volumetric printing, as a novel bioprinting technology, projects a three-dimensional pattern containing model slice information and adjusts the light dose distribution to rapidly aggregate and print the substrate. This overcomes the geometric limitations of traditional 3D printing's layer-by-layer stacking and avoids delamination effects. However, the bio-ink used in volumetric printing must be pre-placed in the forming cavity, making it difficult to precisely control the spatial distribution of different materials when manufacturing multi-material parts.

[0003] Furthermore, the forming accuracy of the aforementioned 3D printing processes is limited by the extruded filament diameter and projected light resolution, making it difficult to systematically construct macro- and micro-scale structures while maintaining manufacturing efficiency. Currently, a common solution is to use porous soft materials for cell-containing printing and induce the generation of microvascular structures. However, the microstructures constructed using this approach are disordered and cannot be customized, which limits the functionalization of the constructed models. Summary of the Invention

[0004] The summary section of this application is intended to provide a brief overview of the concepts, which will be described in detail in the detailed description section below. This summary section is not intended to identify key or essential features of the claimed technical solutions, nor is it intended to limit the scope of the claimed technical solutions.

[0005] In order to overcome the shortcomings of the prior art, the present invention provides a manufacturing system and method for soft material multi-scale structures.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a manufacturing system for soft material multi-scale structures, comprising: an extrusion deposition module including multiple nozzles; a first moving module for loading the extrusion deposition module and driving it to move in three-dimensional space; a suspension medium container located below the extrusion deposition module for filling with suspension medium; a projection module for projecting pattern light containing model slice information onto the suspension medium container, providing curing energy and information for the printing substrate; a laser etching module for emitting laser light and etching the workpiece within the suspension medium container to construct a microstructure; a turntable for supporting the suspension medium container and driving it to rotate 360 ​​degrees; an optical adjustment module located between the projection module and the suspension medium container for adjusting the optical path, projection area size, geometric aberrations, and resolution optical parameters of the pattern light projected by the projection module; a control system for coordinating and controlling the spatial movement, process sequence, and parameter design of the extrusion deposition module, projection module, and laser etching module; and a second moving module on which the laser etching module is located and moves together.

[0007] Furthermore, the number of nozzles is greater than or equal to two, the nozzles are filled with soft biological material, and the top of the nozzle is connected to an air supply pipe.

[0008] Furthermore, the spatial movement speed of the nozzle ranges from 1 to 30 mm / s, and the nozzle needle is a capillary or ordinary needle with an outer diameter of 0.1 mm to 1 mm.

[0009] Furthermore, bio-soft materials include silk fibroin, collagen, methacrylamide gelatin bio-ink, or hydrogels with photosensitive properties.

[0010] Furthermore, the optical adjustment module includes optical feature components and optical elements. The transmittance of the optical adjustment module in the projection light wavelength range is greater than or equal to 90%. The optical parameters of the optical adjustment module are matched with the optical parameters of the printing ink and the suspension medium container, which can convert the projection light emitted by the projection module into parallel light or near-parallel light, and then incident on the suspension medium container to achieve the curing of the bio-soft material.

[0011] Furthermore, the suspended medium container is a columnar transparent container with equal curvature, and has a transmittance of greater than or equal to 90% in the projection wavelength range of the projected light.

[0012] Furthermore, the suspension medium includes a mixture of carbomer or poloxamer 127 and hydroxypropyl methylcellulose.

[0013] Furthermore, the moving module includes multiple guide rails and multiple linear motors, with the multiple guide rails in different directions being perpendicular to each other in space.

[0014] In another aspect, this application also discloses a method for manufacturing soft material multi-scale structures using the manufacturing system for soft material multi-scale structures as described above, comprising the following steps:

[0015] Step 1: Design the structure according to the required performance, model the designed structure using 3D software, slice the 3D model to be printed and generate a printing path file, optimize and process the slice data based on tomographic imaging technology, organize and convert it into image data, and load it into the control module.

[0016] Step 2: Configure the number of nozzles according to the required material type, adjust the air pressure to make the nozzles stably extrude the bio-soft material, adjust the moving device to make one nozzle descend and immerse itself in the suspension medium. While the nozzle moves in the suspension medium, it extrudes the bio-soft material. The extruded bio-soft material forms filaments as the nozzle moves.

[0017] Step 3: When the designed structure contains multiple materials, the first moving module switches the extrusion nozzle during the printing process, so that the original nozzle returns to the initial point, and the new nozzle extrudes the new material to continue printing;

[0018] Step 4: After printing one layer of structure, the printhead is raised according to the printing layer height, and the process of Step 2 and Step 3 above is repeated until the pre-printing work is completed;

[0019] Step 5: Adjust the projection module to output image sequences based on the information of the designed 3D model to form a 3D pattern light. The illumination intensity of the projection module is between 500mW / cm2 and 2000mW / cm2. Adjust the optical adjustment module to convert the adjusted projection light into parallel light or near-parallel light.

[0020] Step 6: Start the turntable and adjust the projection module according to the turntable speed so that the preloaded image sequence is projected into the molding cavity according to the turntable speed. The pre-deposited bio-soft material is gradually irradiated by the three-dimensional area and solidifies until the three-dimensional model is solidified. Then, stop the turntable and turn off the projection module.

[0021] Step 7: Start the laser etching module. Based on the designed structure of the model, adjust the angle using the turntable, move the laser emitter to align with the small-sized structure, and begin laser etching to generate the customized structure until all structures are manufactured. Preferably, the laser power is 5~50W, and the etching speed is 20~80mm / s.

[0022] Step 8: Clean up and recycle the uncured biomaterial, remove the printed parts, and perform post-processing to bring the printed parts to the required shape specifications.

[0023] The advantages of this invention are:

[0024] 1. This invention enables cross-scale manufacturing of bio-soft materials based on embedded extrusion printing, volumetric printing, and laser etching technologies. It achieves the manufacturing of macroscopic structures (sub-millimeter scale) through pre-deposition and one-time volumetric solidification of various soft materials, and the manufacturing of microstructures (micrometer scale) through point etching of soft materials.

[0025] 2. This invention utilizes embedded multi-material extrusion printing technology and volumetric printing technology to achieve integrated fabrication of various soft material structures, avoiding the effects of delamination.

[0026] 3. This invention has extensive applicability. By changing the composition of the photosensitive bio-soft material and the composition of the suspension medium, the local mechanical properties of the prepared components can be specialized, and it can be further widely used in the construction of gradient environments in biological tissues. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application.

[0028] Furthermore, throughout the accompanying drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the elements are not necessarily drawn to scale.

[0029] In the attached diagram:

[0030] Figure 1 This is a schematic diagram of the printing process of a manufacturing system and method for a soft material multi-scale structure according to the present invention.

[0031] Figure 2 This is a flowchart illustrating the printing process of a method for manufacturing a soft material multi-scale structure according to the present invention.

[0032] Figure 3 This is a schematic diagram of the manufacturing system device for a soft material multi-scale structure according to the present invention.

[0033] Figure 4 This is a front view of a component with macroscopic and microscopic structures printed according to the present invention.

[0034] Figure 5 This is a cross-sectional view at point AA of a component with macroscopic and microscopic structures printed for this invention.

[0035] Figure 6 This is a cross-sectional view at the CC section of a component with macro- and micro-structures printed according to the present invention.

[0036] Figure 7 An isometric side view of a component with macro- and micro-structures is printed for this invention.

[0037] The meanings of the reference numerals in the figure are as follows: Detailed Implementation

[0038] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0039] It should also be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other.

[0040] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0041] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0042] The names of messages or information exchanged between multiple devices in the embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of such messages or information.

[0043] This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0044] like Figure 3 As shown, a manufacturing system for a soft material multi-scale structure includes:

[0045] Optical adjustment module 1: It consists of components or optical elements with optical characteristics, located between the projection module 10 and the suspension medium container 2, and is used to adjust the optical path, projection area size, geometric aberration, and resolution optical parameters of the pattern light projected by the projection module 10.

[0046] Suspended medium container 2: It is a columnar transparent container with equal curvature, and should have a light transmittance of greater than or equal to 90% in the projection wavelength range of the projected light. It is filled with suspended medium to support the pre-deposited material and the components that have been deposited.

[0047] Extrusion deposition module 4: It is fixed to the corresponding first moving module 3 and includes multiple nozzles 5 with the same structure. The nozzles 5 are filled with different soft materials. The materials required for extrusion according to the model can be deposited in the suspension medium container 2 to achieve pre-deposition of the component. Among them, the bio-soft materials refer to viscoelastic materials with an elastic modulus of less than 5 kPa. The preferred bio-soft materials in this system are: silk fibroin, collagen, methacrylamide gelatin bio-ink and other hydrogels with photosensitive properties.

[0048] Laser etching module 8: It is fixed to the corresponding second moving module 7 and contains a laser generator. It uses femtosecond lasers to etch materials at the micrometer scale to construct customized microstructures.

[0049] Turntable 9: It is used to support the suspended medium container 2 and can rotate 360 ​​degrees to ensure that curing energy and information are evenly transferred to the printing substrate from all sides;

[0050] Projection module 10: It can project three-dimensional pattern light containing model slice information onto the suspended medium container 2 and adjust the light dose distribution to provide curing energy and information for the printing substrate, thereby realizing the rapid forming of soft materials;

[0051] like Figure 1 , Figure 2 As shown, as another aspect of this application, this application also discloses a method for manufacturing soft material multi-scale structures using the aforementioned soft material multi-scale structure manufacturing system, specifically including the following steps:

[0052] Step 1: Design the structure according to the required performance, model the designed structure using 3D software, slice the 3D model to be printed and generate a printing path file, optimize and process the slice data based on tomographic imaging technology, organize and convert it into image data, and load it into the control system.

[0053] Step 2: Configure the number of nozzles 5 according to the required material type, adjust the air pressure to make the nozzles stably extrude the bio-soft material, adjust the moving device 3 to make one nozzle 5 descend and immerse itself in the suspension medium, and extrude the bio-soft material while the nozzle 5 moves in the suspension medium. The extruded bio-soft material forms filaments as the nozzle 5 moves.

[0054] Step 3: When the designed structure contains multiple materials, the first moving module 3 switches the extrusion nozzle 5 during the printing process, so that the original nozzle 5 returns to the initial point, and the new nozzle 5 extrudes the new material to continue printing;

[0055] Step 4: After printing one layer of structure, the printhead 5 is raised according to the printing layer height, and the process of Step 2 and Step 3 above is repeated until the pre-printing work is completed;

[0056] Step 5: Adjust the projection module 10 to output image sequence according to the information of the designed 3D model to form a 3D pattern light. The light intensity of the projection module 10 is between 500mW / cm2 and 2000mW / cm2. Adjust the optical adjustment module 1 to convert the adjusted projection light into parallel light or near-parallel light.

[0057] Step 6: Start the turntable 9 and adjust the projection module 10 according to the turntable speed so that the preloaded image sequence is projected into the molding cavity according to the turntable 9 speed. The pre-deposited bio-soft material is gradually irradiated by the three-dimensional area and solidifies until the three-dimensional model is solidified. Then, stop the turntable and turn off the projection module.

[0058] Step 7: Activate laser etching module 8. Based on the designed structure of the model, adjust the angle using turntable 9, move the laser emitter to align with the small-sized structure, and initiate laser etching to generate the customized structure until all structures are manufactured. Preferably, the laser power is 5~50W, and the etching speed is 20~80mm / s.

[0059] Step 8: Clean up and recycle the uncured biomaterial, remove the printed parts, and perform post-processing to bring the printed parts to the required shape specifications.

[0060] In summary, by systematically adjusting the coordination between multiple processes during manufacturing, efficient manufacturing of components with multiple materials and cross-scale macro-micro structures can be achieved. By adjusting parameters such as nozzle movement speed, soft material mechanical properties, projection light intensity, and laser power during the printing process, the size, density, scale span, and forming rate of the printed structure can be adjusted. Therefore, this system and method can realize cross-scale manufacturing of complex heterogeneous structures.

[0061] like Figure 4-7 The image shows an embodiment of the manufacturing method proposed in this invention. This embodiment is a multi-material double-layer hollow straight tube, and its inner layer has a microporous structure (micrometer level). The manufacturing system and method proposed in this invention can accurately realize the manufacturing of this embodiment. The invention will be further described below through this embodiment.

[0062] A 3D model file of the part to be printed is created, and its structural features are analyzed. A path planning file for the required pre-deposited materials is created. According to the analysis, two types of pre-deposited materials are required in this embodiment, possessing macroscopic (centimeter-level) and microscopic (central micron-level pores) cross-scale structures. Structure layer 11 has 5 printing layers, and structure layer 12 has 5 printing layers. Pre-deposited slices are made for the structure layer models. The macroscopic structural features of the part to be printed are analyzed. Based on tomographic scanning technology, the slice data is optimized and processed, converted into image data, and the corresponding pattern light for the 3D model file is generated and loaded into the control system. A suspension medium is prepared by mixing poloxamer 127 and hydroxypropyl methylcellulose at 60°C in a 5:2 ratio to form a suspension. After cooling to room temperature, the suspension medium is transferred to a container for later use. The corresponding bio-soft materials collagen and 5% by mass of methacrylamide gelatin for structure layers 11 and 12 are respectively filled into the nozzle, ready for printing. According to the pre-deposited path planning, the printing air pressure is adjusted to approximately 1.5 bar at room temperature. Approximately r is used to stably extrude two types of biomaterials into filaments through the nozzle. The filament size matches the layer height of the slice, with a default value of 200 μm and an aspect ratio of 1. The moving module is adjusted, and the nozzle moving speed is set to 10 mm / s, causing one nozzle to descend into the suspension medium container. While moving in the suspension medium, the nozzle extrudes the biomaterial, which forms filaments as the nozzle moves. When one material is printed, the moving module switches the extrusion nozzle. The original nozzle returns to its origin, and the new nozzle replaces the original nozzle position, extruding new material and continuing printing. The printing sequence for each layer is from the inside out, from the center to the outer perimeter. After printing one layer, the nozzle is raised according to the printing layer height, and the above steps are repeated until the pre-printing work is completed. The projection module is adjusted to output an image sequence based on the information of the designed 3D model, forming a 3D pattern light. The light intensity of the projection module is set to 1000 mW / cm2. The optical adjustment module is slowly adjusted until the adjusted projection light is converted into parallel or near-parallel light. The turntable is activated, and the projection module is adjusted according to the turntable speed to project the pre-loaded image sequence into the molding cavity. The pre-deposited bio-soft material is gradually irradiated by the three-dimensional region, causing it to solidify. Once the three-dimensional model is solidified, the turntable is stopped, and the projection module is turned off, resulting in a multi-material tubular part with a macroscopic structure. The laser etching module is then activated. Based on the designed structure of the model, the turntable angle is adjusted, and the laser emitter is moved to align with the small-sized structure. Laser etching is then initiated to generate customized structures until all structures are manufactured. Preferably, the initial laser power is set to 30W, and the etching speed is 20mm / s, resulting in a multi-material part with a macro- and micro-scale cross-scale structure. The uncured bio-soft material is cleaned and recycled, the printed part is removed, and post-processing is performed to bring the printed part to the required shape specifications.

[0063] The above description is merely a selection of preferred embodiments of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in the embodiments of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of this disclosure.

Claims

1. A manufacturing system for soft material cross-scale structures, characterized by: The application relates to a 3D printing device and a 3D printing method. The device comprises: an extrusion deposition module comprising a plurality of nozzles; a first moving module for loading the extrusion deposition module and capable of moving the extrusion deposition module in a three-dimensional space; a suspension medium container below the extrusion deposition module for loading a suspension medium; a projection module for projecting pattern light containing model slice information to the suspension medium container to provide solidification energy and information of a printing substrate; a laser etching module for emitting laser and etching a workpiece in the suspension medium container to build a microstructure; a turntable for carrying the suspension medium container and capable of rotating the suspension medium container by 360 degrees; an optical adjustment module between the projection module and the suspension medium container for adjusting the light path, projection size, geometric aberration and resolution optical parameters of the pattern light projected by the projection module; a control system for coordinating and controlling the spatial movement, process timing and parameter design of the extrusion deposition module, the projection module and the laser etching module; a second moving module; 2. The system for manufacturing soft material cross-scale structures of claim 1, wherein: the laser etching module moves together with the second moving module.

3. The system for manufacturing soft material cross-scale structures of claim 2, wherein: The number of the nozzles is greater than or equal to two, the nozzles are filled with biological soft materials, and the top ends of the nozzles are connected with gas conveying pipes.

4. The system for manufacturing soft material cross-scale structures of claim 2, wherein: The space movement speed range of the nozzles is 1-30 mm / s, the needle heads of the nozzles are capillary tubes or common needle heads, and the outer diameters of the needle heads are 0.1 mm-1 mm.

5. The system for manufacturing soft material cross-scale structures of claim 1, wherein: The biological soft materials include silk fibroin, collagen, methacrylated gelatin biological ink or hydrogel with photosensitive properties.

6. The system for manufacturing soft material cross-scale structures of claim 1, wherein: The optical adjustment module comprises optical characteristic components and optical elements, the light transmittance of the optical adjustment module in the wavelength segment of the projection light is greater than or equal to 90%, the optical parameters of the optical adjustment module are matched with the optical parameters of the printing ink and the suspension medium container, the projection light emitted by the projection module can be converted into parallel light or near-parallel light, and the parallel light or near-parallel light is incident into the suspension medium container to realize the solidification of the biological soft materials.

7. The system for manufacturing soft material cross-scale structures of claim 1, wherein: The suspension medium container is an equal-curvature columnar light-transmitting container, and the light transmittance of the suspension medium container in the wavelength segment of the projection light is greater than or equal to 90%.

8. The system for manufacturing soft material cross-scale structures of claim 1, wherein: The suspension medium comprises a mixture of carbomer or poloxamer 127 and hydroxypropyl methyl cellulose.

9. A method of fabricating a soft material cross-scale structure using a system for fabricating soft material cross-scale structures as claimed in any one of claims 1-8, characterized by: The moving module comprises a plurality of guide rails and a plurality of linear motors, and the guide rails in different directions are perpendicular to each other in space. The method comprises the following steps: Step one: designing a structure according to required performance, modeling the designed structure through three-dimensional software, slicing a three-dimensional model to be printed and generating a printing path file, optimizing and processing slice data based on tomography technology, arranging and converting the slice data into image data, and loading the image data into a control module; Step two: configuring the number of nozzles according to required material types, adjusting air pressure to make the nozzles stably extrude biological soft materials, adjusting a moving device to make one nozzle descend into the suspension medium, extruding the biological soft materials while the nozzle moves in the suspension medium, and forming filaments with the biological soft materials along with the movement of the nozzle. Step three: when the designed structure has multiple materials, switch the extrusion nozzle by the first moving module during printing, so that the original nozzle returns to the initial point, the new nozzle extrudes new material, and the printing continues; Step four: after printing a layer of structure, the nozzle is lifted according to the printing layer height, and the above steps two and three are repeated until the pre-printing work is completed; Step five: adjust the projection module to output image sequence according to the information of the designed three-dimensional model to form three-dimensional pattern light, wherein the light intensity of the projection module is between 500mW / cm2 and 2000mW / cm2, and the optical adjustment module is adjusted so that the adjusted projection light is converted into parallel light or near parallel light; Step six: start the rotating table and adjust the projection module according to the rotating speed of the rotating table to project the preloaded image sequence into the forming cavity according to the rotating speed of the rotating table, wherein the pre-deposited biological soft material is subjected to gradually accumulated three-dimensional area irradiation and solidification until the three-dimensional model is solidified, then stop the rotating table and close the projection module; Step seven: start the laser etching module, adjust the angle of the rotating table according to the model design structure, move the laser emitter to align with the small size structure position, and open the laser etching to produce customized structure, until all the structures are manufactured, the laser power is 5~50W, and the etching speed is 20~80mm / s; Step eight: clean and recycle the un-solidified biological soft material, take out the printed part, and perform post-processing to make the printed part meet the required shape index.

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