3D model printing methods, apparatus, electronic devices and readable storage media

Abstract

This application relates to a method, apparatus, and electronic device for printing three-dimensional models. The method includes: acquiring three-dimensional model data; determining cavity data from the three-dimensional model data; and scheduling a corresponding printing strategy based on the cavity data for printing. The printing strategy includes at least one of adjusting the liquid level, controlling the waiting time, controlling the discharge height, controlling the motion parameters of the forming platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity. This application allows the user to automatically adjust the printing strategy adaptively based on the slice structure of the model without changing the model structure, adjusting the model's orientation, or modifying the printing parameters. This avoids edge defects in the printed model with cavity structures, improves printing quality, and increases printing efficiency.

Description

Technical Field

[0001] This application relates to the field of 3D printing technology, and in particular to a method, apparatus, electronic device and computer-readable storage medium for printing three-dimensional models. Background Technology

[0002] In photopolymer 3D printing, the presence of cavities (or inverted cup-like structures) in the printed part can affect print quality, leading to poor surface quality or even damage. For example... Figure 1 As shown, if a 3D model includes an inverted cup-shaped structure in its printed portion, during the printing process, the printed part adheres layer by layer to the molding platform. After each layer is printed, the molding platform first rises, then falls, and then contacts the resin surface. The cavity of the printed part and the molding area of ​​the material tray form a closed cavity. As the printed part descends, the gas inside the cavity forces the liquid below to flow outwards. When the printed part falls to a depth of one layer from the molding area of ​​the material tray, exposure begins. At this point, because some liquid continues to flow outwards, incompletely cured material is formed, resulting in a large amount of residue and causing defects on the surface of the printed part.

[0003] To address these issues, common solutions include altering the design of the original 3D model, such as opening holes in closed cavities to allow liquid to drain out; changing the model's orientation to avoid forming closed cavities; or, once a cavity is identified, printing the entire model at a low speed to avoid printing defects in the cavity area.

[0004] The methods described above require users to have some understanding and experience with photopolymer 3D printing, and these methods also have certain limitations. For example, creating openings can damage the original model structure; changing the model's orientation requires additional support and increases material consumption; and it may not completely avoid the inverted cup rim structure. Printing the entire model at a low speed will severely impact printing time and efficiency.

[0005] In summary, due to the technical barriers and shortcomings of industry solutions to this problem, most users are aware of the problem but are unable to solve it. Users who are aware of the aforementioned industry solutions need to spend a lot of time adjusting the model structure, resulting in excessively long printing times and significantly reducing the convenience of printing. Summary of the Invention

[0006] In view of this, in order to solve some or all of the above-mentioned technical problems, embodiments of this application provide a three-dimensional model printing method, apparatus, electronic device, and computer-readable storage medium.

[0007] In a first aspect, embodiments of this application provide a three-dimensional model printing method applied to a 3D printing device, the 3D printing device including a molding platform, characterized in that the method includes: acquiring three-dimensional model data; determining cavity data from the three-dimensional model data; scheduling a corresponding printing strategy according to the cavity data for printing; wherein the printing strategy includes at least one of adjusting liquid level, controlling waiting time, controlling drainage height, controlling molding platform motion parameters, adjusting exposure strategy, and adjusting image data corresponding to the cavity.

[0008] Secondly, embodiments of this application provide a three-dimensional model printing device, applied to a 3D printing equipment, the 3D printing equipment including a molding platform, characterized in that the device includes: an acquisition module for acquiring three-dimensional model data; a first determination module for determining cavity data from the three-dimensional model data; and a printing module for scheduling a corresponding printing strategy based on the cavity data to perform printing; wherein the printing strategy includes at least one of adjusting liquid level, controlling waiting time, controlling discharge height, controlling molding platform motion parameters, adjusting exposure strategy, and adjusting image data corresponding to the cavity.

[0009] Thirdly, embodiments of this application provide an electronic device, including: a memory for storing a computer program; and a processor for executing the computer program stored in the memory, wherein when the computer program is executed, it implements the method of any embodiment of the three-dimensional model printing method of the first aspect of this application.

[0010] Fourthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the method of any embodiment of the three-dimensional model printing method of the first aspect described above.

[0011] Fifthly, embodiments of this application provide a computer program including computer-readable code that, when executed on a device, causes a processor in the device to implement the method of any embodiment of the three-dimensional model printing method of the first aspect described above.

[0012] The three-dimensional model printing method, apparatus, electronic device, and computer-readable storage medium provided in this application determine cavity data from the three-dimensional model data to be printed, and schedule corresponding printing strategies for printing based on the cavity data. The printing strategies include at least one of adjusting liquid level, controlling waiting time, controlling drainage height, controlling molding platform motion parameters, adjusting exposure strategy, and adjusting image data corresponding to the cavity. This allows the user to automatically adjust the printing method adaptively based on the slice structure of the model without changing the model structure, adjusting the model's orientation, or modifying the printing parameters. This avoids edge defects in the printed model with cavity structure, improves printing quality, and increases printing efficiency. Attached Figure Description

[0013] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0016] Figure 1 A schematic diagram of the printing process for a closed cavity;

[0017] Figure 2 A schematic diagram of an optional 3D printing device provided for an embodiment of this application;

[0018] Figure 3 A schematic diagram of another optional 3D printing device provided for an embodiment of this application;

[0019] Figure 4A -B is a slice diagram of a three-dimensional model forming a closed cavity provided in an embodiment of this application;

[0020] Figure 4C-4F A schematic diagram of a three-dimensional model forming a closed cavity provided in an embodiment of this application;

[0021] Figure 5 A flowchart illustrating a three-dimensional model printing method provided in this application embodiment;

[0022] Figure 6 A flowchart illustrating another three-dimensional model printing method provided in this application embodiment;

[0023] Figure 7A A schematic diagram of a three-dimensional model of a cavity formed during printing, provided for an embodiment of this application;

[0024] Figure 7B A schematic diagram of a cavity image provided in an embodiment of this application;

[0025] Figure 8 A flowchart illustrating another three-dimensional model printing method provided in this application embodiment;

[0026] Figure 9 A schematic diagram of a three-dimensional model including a small through hole, provided for an embodiment of this application;

[0027] Figure 10 A flowchart illustrating another three-dimensional model printing method provided in this application embodiment;

[0028] Figure 11 A flowchart illustrating another three-dimensional model printing method provided in this application embodiment;

[0029] Figure 12 A schematic diagram of a slice of a three-dimensional model provided in an embodiment of this application;

[0030] Figure 13A A schematic diagram of a cavity with a relatively large wall thickness provided for an embodiment of this application;

[0031] Figure 13B A schematic diagram of the split filled area image provided in an embodiment of this application;

[0032] Figure 13C A schematic diagram of the segmented contour region image provided in an embodiment of this application;

[0033] Figure 14 This is a schematic diagram of the structure of a three-dimensional model printing device provided in an embodiment of this application;

[0034] Figure 15 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0035] The above figures include the following reference numerals:

[0036] 11- Molding platform; 12- Material tray; 13- Light source mechanism; 14- Printed part; 15- Resin liquid surface; 16- Molding area; 17- Structural surface. Detailed Implementation

[0037] Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0038] Those skilled in the art will understand that the terms "first" and "second" in the embodiments of this application are only used to distinguish different steps, devices or modules, and do not represent any specific technical meaning, nor do they indicate the logical order between them.

[0039] It should also be understood that in this embodiment, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0040] It should also be understood that any component, data or structure mentioned in the embodiments of this application can generally be understood as one or more unless explicitly defined or given contrary guidance in the context.

[0041] Furthermore, the term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "or" relationship.

[0042] It should also be understood that the description of the various embodiments in this application emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0043] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0044] Techniques, circuits, and devices known to a person skilled in the art may not be discussed in detail, but where appropriate, such techniques, circuits, and devices should be considered part of the specification.

[0045] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0046] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. To facilitate understanding of the embodiments of this application, the application will be described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0047] To address the technical problem of poor printing quality of models with closed cavity structures in existing technologies, this application provides a three-dimensional model printing method that can adaptively adjust the printing method for models with closed cavity structures, thereby improving printing quality and efficiency.

[0048] Figure 5This is a flowchart illustrating a three-dimensional model printing method provided in an embodiment of this application. This method can be applied to a 3D printing device, which includes a forming platform. The executing entity of this method can be the 3D printing device itself, or one or more electronic devices such as a laptop, desktop computer, portable computer, or server. These electronic devices can communicate with the 3D printing device to execute the method and control the 3D printing device to perform printing. Furthermore, the executing entity of this method can be hardware or software. When the executing entity is hardware, it can be one or more of the aforementioned electronic devices. For example, a single electronic device can execute this method, or multiple electronic devices can cooperate with each other to execute this method. When the executing entity is software, this method can be implemented as multiple software programs or software modules, or as a single software program or software module. No specific limitations are made here.

[0049] When 3D printing, you can first create a 3D model of the part to be printed, and then slice the 3D model of the part to be printed layer by layer. When printing, you can start from the first slice model. Based on the previous slice model that has been successfully printed, you can print each slice model in turn, and finally get a complete 3D model of the part to be printed. The part to be printed is the object to be printed in 3D printing. Figure 2 This is a schematic diagram of an optional 3D printing device provided according to an embodiment of this application, commonly referred to as under-projection technology. Figure 2 As shown, this is an optional 3D printing device provided in the embodiments of this application. When printing each layer of the slice model, a projection image can be generated according to the shape of the slice model. The projection image is sent to the light source mechanism 13, such as an optical engine, LCD, etc. The light source mechanism is the light source device. The light source mechanism 13 can project the projection image onto the molding area 16 in the material tray 12 filled with polymerizable liquid (such as photosensitive material), that is, onto the structural surface 17, that is, the surface of the bottom of the material tray in contact with the resin. The polymerizable liquid on the molding area will solidify between the molding platform 11 and the structural surface 17 under the irradiation of the light emitted by the light source mechanism 13 to form a solid or semi-solid polymer. At this time, the molding platform 11 can be controlled to move so that the solid or semi-solid polymer separates from the structural surface 17 layer by layer. This process of layer-by-layer solidification-separation-solidification-separation is repeated to finally form a model that matches the projection image, that is, the printed part 14.

[0050] Figure 3 This is a schematic diagram of another optional 3D printing device provided according to an embodiment of this application, commonly referred to as top projection technology. For example... Figure 3As shown, this is an optional 3D printing device provided in the embodiments of this application. When printing each layer of the slice model, a projection image can be generated according to the shape of the slice model. The projection image is sent to the light source mechanism 13, such as an optical engine. The light source mechanism is the light source device. The light source mechanism 13 can project the projection image onto the molding area 16 in the material tray 12 filled with polymerizable liquid (such as photosensitive material), that is, onto the construction surface 17, that is, onto the surface of the resin at the top of the material tray. The polymerizable liquid on the molding area 16 will solidify between the molding platform 11 and the construction surface 17 under the irradiation of the light emitted by the light source mechanism 13 to form a solid or semi-solid polymer. At this time, the molding platform 11 can be controlled to move so that the solid or semi-solid polymer separates from the construction surface layer by layer. This process of layer-by-layer solidification-separation-solidification-separation is repeated to finally form a model that matches the projection image, that is, the printed part 14.

[0051] The cavity mentioned in this application refers to a cavity within a 3D model (3D object), such as a vase, bowl, cup, dental mold, parts, toy, or headphone shell. Since these objects have internal cavities, their 3D models inevitably also contain cavities. In the 3D printing process, the 3D model of the object is first sliced ​​to obtain a collection of slices, which are then printed layer by layer to complete the 3D printing. In the 3D model, if the nth layer of the slice is a complete solid cross-section, and from the (n+1)th layer to the (n+m)th layer is a ring-shaped wall cross-section, then a cavity is determined to exist. The solid cross-section of the nth layer, the wall cross-section of the (n+m)th layer, and the structural surface of the forming area form a closed cavity. This can cause the resin inside the cavity to be unable to escape during printing, or the gas inside the cavity to force the liquid below to flow outwards. When the next layer begins to be exposed, some liquid continues to flow outwards, forming incompletely cured material, which in turn produces a large amount of residue, causing defects on the surface of the printed part and potentially leading to warping.

[0052] Figures 4A-4F This is a schematic diagram of a three-dimensional model of a cavity formed according to an embodiment of this application, as shown below. Figure 4A As shown, the nth layer is a complete solid cross-section. From the (n+1)th layer to the (n+m)th layer, there are annular wall cross-sections. The (n+m+1)th layer is again a complete solid cross-section. At this point, the 3D model has a closed cavity inside, such as a hollow sphere model. Figure 4B As shown, the nth layer is a complete solid cross-section, and from the (n+1)th layer to the (n+m)th layer, they are annular wall cross-sections. At this point, the 3D model is an open cavity, such as a water glass or a vase. For this type of model, the bottom wall, side walls, and the structural surfaces of the molding area form a closed cavity, i.e., a closed cavity.

[0053] like Figure 4C-4FAs shown in the figure, A1, A2, A3, B1, B2, B3, and C1 are cavity regions. A 3D model may contain one or multiple cavities. The location, shape, volume, wall thickness, and number of cavities may be the same or different. The number of slice layers containing cavities, as well as the area, location, shape, wall thickness, and number of cross-sections of each slice layer containing cavities, may also be the same or different. Furthermore, the area, location, shape, wall thickness, and number of cavities within the cross-sections may also be the same or different. Therefore, it is necessary to identify cavity information in order to schedule appropriate printing strategies.

[0054] like Figure 5 As shown, the method specifically includes:

[0055] Step 501: Obtain 3D model data.

[0056] In this embodiment, the three-dimensional model data refers to various data of the three-dimensional model to be printed by the 3D printing equipment, such as the size, wall thickness, and position of the three-dimensional model.

[0057] Step 502: Determine the cavity data from the 3D model data.

[0058] In this embodiment, cavity data refers to the relevant data of cavities in the three-dimensional model. For example, cavity data includes data such as the location, shape, wall thickness, and number of cavities.

[0059] Step 503: Based on the cavity data, schedule the corresponding printing strategy to perform printing.

[0060] In this embodiment, the printing strategy includes at least one of the following: adjusting the liquid level, controlling the waiting time, controlling the liquid discharge height, controlling the motion parameters of the molding platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity.

[0061] Specifically, when the 3D model includes cavity areas, the printing process for these cavities presents problems as described in the background section. Therefore, a printing strategy can be set for the cavity areas. The aforementioned adjustment of the liquid level refers to timely replenishment of liquid printing material into the tray to prevent air from entering the cavity areas of the model. Figure 2 and Figure 3As shown, as printing progresses, the printing material (e.g., resin) is continuously consumed, and the resin level 15 will drop. It is necessary to replenish the printing material promptly to maintain the liquid level at a certain height, preventing air from entering the cavity area of ​​the model. The aforementioned control waiting time refers to the period during which the molding platform, carrying the bottom (or top) of the printed part, descends / rises to a certain distance from the molding area, and then waits for the liquid to stop flowing, allowing the resin in the molding area to stabilize. The distance between the bottom (or top) of the printed part and the molding area during this waiting time is the discharge height. The aforementioned molding platform motion parameters include motion speed and motion distance. The aforementioned exposure strategy includes segmented exposure and different exposure times. The aforementioned adjustment of the image data corresponding to the cavity refers to dividing the sliced ​​image and printing the printing section into multiple parts sequentially to eliminate defects at the cavity edges.

[0062] As an example, a printing strategy could include: controlling the forming platform to descend to a distance of one layer thickness from the bottom (or top) of the tray and then stopping its movement, waiting for a certain period of time (e.g., 10 seconds) until the liquid stops flowing, before resuming printing in the normal manner. Another example is that a printing strategy could include: controlling the liquid replenishment device to ensure that the liquid level of the printing material in the tray is higher than a preset height, ensuring that no air enters the sealed cavity during printing.

[0063] It should be noted that the above printing strategy can be applied to the entire 3D model, that is, the same strategy is used when printing the entire 3D model to eliminate printing defects caused by closed cavities; or different printing strategies can be set for different parts of the 3D model, for example, a cavity-specific printing strategy can be set for cavity parts, and a conventional printing strategy can be used for non-cavity parts.

[0064] The 3D model printing method provided in this application determines cavity data from the 3D model data to be printed, and schedules a corresponding printing strategy for printing based on the cavity data. The printing strategy includes at least one of adjusting the liquid level, controlling the waiting time, controlling the discharge height, controlling the motion parameters of the forming platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity. This allows the user to automatically adjust the printing method adaptively based on the slice structure of the model without changing the model structure, adjusting the model's orientation, or modifying the printing parameters. This avoids edge defects in the printed model with cavity structure, improves printing quality, and increases printing efficiency.

[0065] In some optional implementations of this embodiment, such as Figure 6 As shown, step 503 above includes:

[0066] Step 5031: Based on the cavity data, determine the cavity and non-cavity parts of the three-dimensional model.

[0067] In this context, the cavity portion of the 3D model refers to the closed cavity formed between the structural surface of the printing material forming area and the printed part during the printing process; the other portions are the non-cavity portions. Electronic devices can horizontally segment the 3D model based on the cavity structural features represented by the cavity data; the segmentation section is the boundary between the cavity and non-cavity portions. It should be understood that the number of cavity and non-cavity portions can each be at least one.

[0068] Step 5032: For the cavity part, schedule the corresponding cavity printing strategy for printing; for the non-cavity part, schedule the corresponding non-cavity printing strategy for printing.

[0069] The cavity printing strategy may include at least one of the following strategies for the cavity portion: adjusting the liquid level, controlling the waiting time, controlling the discharge height, controlling the motion parameters of the molding platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity. The non-cavity printing strategy may include at least one of the following strategies for the non-cavity portion: adjusting the liquid level, controlling the waiting time, controlling the discharge height, controlling the motion parameters of the molding platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity.

[0070] As an example, for hollow sections, strategies such as setting a longer drainage waiting time, a higher drainage height, and dividing the slice image data into filled and outline areas for sequential printing can be used. For non-hollow sections, strategies such as setting a shorter drainage time, a lower drainage height, and printing directly without adjusting the slice image can be used.

[0071] This embodiment achieves targeted application of cavity printing strategies and non-cavity printing strategies for the cavity parts of the 3D model to eliminate printing defects caused by closed cavities formed during printing, and applies non-cavity printing strategies to the non-cavity parts to improve printing speed, thereby balancing printing quality and printing efficiency.

[0072] In some optional implementations of this embodiment, step 502 may include at least one of the following two implementations:

[0073] Method 1: First, identify the entire 3D model to obtain 3D data.

[0074] The three-dimensional data includes at least one of the following: model three-dimensional position information, model shape, model volume, model wall thickness, and number of sub-models. The number of sub-models refers to the number of sub-models included in the overall three-dimensional model. The model three-dimensional position information includes the three-dimensional coordinates of each component of the model. The model shape can be represented by the coordinates of each point on the model's outline. The model wall thickness is the wall thickness of each component of the model. The model volume is the overall volume of the model and the volume of each component.

[0075] Then, the cavity data is determined from the three-dimensional data.

[0076] The cavity data includes at least one of the following: three-dimensional location information of the cavity, cavity shape, cavity volume, cavity wall thickness, and number of cavities. Specifically, the electronic device can analyze the overall three-dimensional data of the model to determine the relevant data of cavities isolated from the outside world, or it can set a through-hole size threshold to determine cavities containing through-holes smaller than the through-hole size threshold from non-closed cavities as closed cavities.

[0077] The three-dimensional model is sliced, and the slices containing cavities in the three-dimensional model are identified as a cavity slice set; each slice in the cavity slice set is identified to obtain cavity data, wherein the cavity data includes at least one of the following: the area, location, shape, wall thickness, and number of the slice cross section, and at least one of the following: the area, location, shape, wall thickness, and number of cavities in the slice cross section.

[0078] Method 2: First, slice the 3D model and identify the slices containing cavities in the 3D model as a set of cavity slices.

[0079] Specifically, the slice thickness can be preset, and the three-dimensional model can be sliced ​​according to the slice thickness to obtain a slice set. Based on the three-position information of the cavity, the slices that coincide with the cavity position are determined from the slice set as the cavity slice set.

[0080] Then, each slice in the cavity slice set is identified to obtain cavity data.

[0081] The cavity data includes at least one of the following: the area, location, shape, wall thickness, and number of the slice cross section, and at least one of the following: the area, location, shape, wall thickness, and number of cavities in the slice cross section.

[0082] This embodiment improves the accuracy of identifying enclosed cavity regions by setting two methods for determining cavity data: overall cavity identification and cavity identification based on slices. The two methods can be used simultaneously or separately, and the specific method can be adapted to the actual application and scenario.

[0083] In some optional implementations of this embodiment, such as Figure 6 As shown, in Method 2 above, each slice in the cavity slice set can be identified by following these steps to obtain cavity data:

[0084] Step 5021: Generate a two-dimensional slice image of each slice in the slice set to obtain a two-dimensional slice image set.

[0085] In this embodiment, the electronic device can import a 3D model of an item that the user wants to print, and then slice the 3D model. Specifically, the slice thickness can be preset, and the 3D model can be sliced ​​according to the slice thickness. The cross-sectional image of each slice is the corresponding 2D slice image.

[0086] Step 5022: Determine the cross-sectional geometric information of each two-dimensional slice image in the set of two-dimensional slice images.

[0087] In this embodiment, the electronic device can identify the two-dimensional slice images of each slice to determine the geometric information of the cross-sectional contour of the three-dimensional model. The cross-sectional geometric information may include information such as the area, position, shape, and cavity wall thickness of the cross-section.

[0088] Step 5023: Determine the cavity data based on the cross-sectional geometric information.

[0089] Among them, cross-sectional geometric information can represent the geometric features of the cavity. Therefore, data representing the cavity can be extracted from the cross-sectional geometric information as cavity data. Cavity data may include, but is not limited to, at least one of the following: cavity shape, number of cavities, cavity wall thickness, etc.

[0090] This embodiment determines the cross-sectional geometric information of each two-dimensional slice image, and then determines the cavity data based on the cross-sectional geometric information, realizing two-dimensional geometric features based on cavities. The cavity data can be determined after slicing the model, which helps to improve the efficiency of determining cavity data.

[0091] In some optional implementations of this embodiment, such as Figure 6 As shown, step 503 includes:

[0092] Step 5031: Based on the cross-sectional geometric information, determine the cavity image subset corresponding to the cavity region from the set of two-dimensional slice images.

[0093] In this embodiment, the electronic device can determine a subset of two-dimensional slice images corresponding to the closed cavity region from a set of two-dimensional slice images based on the geometric features of the cavity. For example... Figure 7A As shown, three models were printed simultaneously, each sliced ​​into 2000 layers, resulting in 2000 two-dimensional slice images. Two of the models include a cavity layer, i.e., an inverted cup rim layer. When the bottom of the inverted cup rim layer contacts the liquid surface in the tray, it forms a closed cavity region. The other model, due to an opening at the top, does not include an inverted cup rim layer. Figure 7B As shown, it displays two-dimensional slice images corresponding to layers 127-954 of the three models. These images constitute a subset of cavity images, corresponding to the closed cavity regions of the two models.

[0094] Step 5032: For each cavity image in the cavity image subset, determine whether the cavity image meets the optimized printing conditions based on the cross-sectional geometric information of the cavity image; if it meets the optimized printing conditions, determine the target cavity printing strategy corresponding to the cavity image, and print the 3D model slice corresponding to the cavity image based on the target cavity printing strategy.

[0095] In this embodiment, the aforementioned optimized printing conditions can be preset conditions indicating that the printing strategy needs to be adjusted because the current 3D model slice to be printed contains closed cavities. That is, when the optimized printing conditions are met, printing defects may occur due to the presence of closed cavities. As an example, the cross-section set information includes information such as cavity area and cavity wall thickness. If the cavity area is greater than a preset area and / or the cavity wall thickness is less than a preset wall thickness, it can be determined that the printing optimization conditions are met.

[0096] When printing optimization conditions are met, a target cavity printing strategy can be executed based on preset printing parameters. For example, a target cavity printing strategy might include: controlling the forming platform to descend to a distance of one layer thickness from the bottom (or top) of the material tray and then stopping its movement, waiting for a certain period (e.g., 10 seconds) until the liquid stops flowing, and then resuming printing in the normal manner. Another example is controlling the liquid replenishment device to ensure the liquid level of the printing material in the tray is higher than a preset height, ensuring that no air enters the sealed cavity during printing.

[0097] It should be noted that step 5032 is performed for each cavity image in the cavity image subset, that is, the same steps are repeated for each cavity image to complete the printing of the 3D model slices corresponding to each cavity image.

[0098] It should be understood that if the cavity image does not meet the optimized printing conditions, the corresponding 3D model slice will be printed according to the conventional process.

[0099] This embodiment determines a subset of cavity images corresponding to the closed cavity region from a set of two-dimensional slice images. Then, based on the cross-sectional geometry of each cavity image, it determines whether the cavity image meets the optimized printing conditions. If it does, it determines the target cavity printing strategy corresponding to the cavity image and prints the corresponding three-dimensional model slice based on the target cavity printing strategy. This allows the user to automatically adjust the printing method adaptively according to the slice structure of the model without changing the model structure, adjusting the model's orientation, or modifying the printing parameters. This avoids edge defects in the printed cavity structure model, improves printing quality, and increases printing efficiency.

[0100] In some optional implementations of this embodiment, such as Figure 8 As shown, step 5031 includes:

[0101] Step 50311: For each two-dimensional slice image in the set of two-dimensional slice images, based on the cross-sectional geometric information of the two-dimensional slice image, determine the difference between the cavity area in the two-dimensional slice image and the cavity area in the previous layer of two-dimensional slice image.

[0102] Specifically, the cross-sectional information of a two-dimensional slice image can include information related to the cross-sectional contour. Based on this information, it can be determined whether the two-dimensional slice image includes cavities (the included cavities are not necessarily closed cavities, but may also be through holes), and the cavity area can be determined. When the two-dimensional slice image includes multiple cavities, the cavity area can be the sum of the areas of the multiple cavities.

[0103] Step 50312: If the difference meets the cavity determination condition and it is determined that the two-dimensional slice image contains a through hole, determine the size of the through hole.

[0104] The above cavity determination condition is to determine whether the current two-dimensional slice image corresponds to a closed cavity.

[0105] Optionally, the cavity determination criteria may include: the difference mentioned above is greater than or equal to a preset value. For example, if the cavity area changes from 0 in the previous slice to a non-zero value in the current slice, a closed cavity is determined to exist, and the two-dimensional slice image corresponding to this slice is a cavity image.

[0106] Specifically, if a cavity appears in a two-dimensional slice image, it can be determined whether the cavity is a through-hole based on the cavity information of the slices preceding that slice. For example, if multiple cavities with overlapping areas appear consecutively starting from the first slice, then the cavity is determined to be a through-hole. Based on the cross-sectional geometry information of each slice, the size of the through-hole can be determined.

[0107] Step 50313: If the size of the through hole is less than or equal to the preset size, the two-dimensional slice image is determined to be a cavity image.

[0108] When the size of the through hole is less than or equal to the preset size, the exhaust speed after the model contacts the liquid surface is low, which will still create a similar effect to a closed cavity, affecting the printing quality. Therefore, the two-dimensional slice image can be identified as a cavity image and printed according to the printing strategy for closed cavities.

[0109] like Figure 9 As shown, it illustrates a schematic diagram of a three-dimensional model. The area indicated by the rectangle in the figure is a gap, which is equivalent to a through hole. Since the size of the gap is small, this area can be identified as a closed cavity region. The corresponding two-dimensional slice image of this area is the cavity image.

[0110] This embodiment improves the accuracy of cavity image determination by setting cavity determination conditions and determining whether a two-dimensional slice image is a cavity image based on the through-hole size. This is achieved by fully considering the actual printing scenario based on the structural characteristics of the closed cavity. As a result, the printing strategy for closed cavities is more adapted to the actual printing scenario, thus improving the printing quality.

[0111] In some optional implementations of this embodiment, such as Figure 10 As shown, in step 5032, for each cavity image in the cavity image subset, the following steps can also be performed:

[0112] Step 50321: Based on the cross-sectional geometric information of the cavity image, determine the ratio of the cavity area to the cross-sectional area of ​​the cavity image.

[0113] Among them, the cross-sectional area is the total area of ​​the cross section of the 3D model in the current slice, and the cavity area is the total area of ​​the closed region without openings enclosed within the cross section.

[0114] Step 50322: If the ratio is greater than or equal to a preset ratio threshold, determine the cavity printing difficulty value of the cavity image based on the cross-sectional geometric information of the cavity image.

[0115] Among them, the cavity printing difficulty value is a quantitative reference parameter when printing a closed cavity area. The higher the cavity printing difficulty value, the greater the impact on the quality of model forming when printing the cavity, and the greater the possibility of quality defects.

[0116] As an example, the printing difficulty value can be calculated based on parameters such as the area, location, shape, and wall thickness of the cavity. For instance, a weight can be set for each parameter, and a weighted sum can be performed to obtain the printing difficulty value. Generally, the rules for calculating the printing difficulty value may include: the larger the area of ​​the closed cavity, the greater the printing difficulty value; the smaller the minimum wall thickness of the closed cavity, the greater the printing difficulty value; and the closer the closed cavity is to other cross-sections, the greater the printing difficulty value.

[0117] Step 50323: If the cavity printing difficulty value is greater than or equal to the preset difficulty threshold, determine that the cavity image meets the optimized printing conditions.

[0118] The preset difficulty threshold can be set in advance according to the actual printing scenario. When the cavity printing difficulty value is greater than or equal to the preset difficulty threshold, it means that when printing in the conventional printing method, the possibility of printing defects in the cavity area is greater, and a targeted cavity printing strategy needs to be set (e.g., increasing the waiting time below the liquid surface).

[0119] This embodiment determines the cavity printing difficulty value when the ratio of cavity area to cross-sectional area is greater than a preset ratio threshold, thereby quantifying the printing difficulty of the cavity. Based on the printing difficulty value, the possibility of printing quality problems when printing a closed cavity can be more accurately reflected, so that the printing method can be adjusted more specifically, further improving the printing quality.

[0120] In some optional implementations of this embodiment, such as Figure 10 As shown, after step 50321, the method further includes:

[0121] Step 50324: If the ratio is less than the preset ratio threshold, it is determined that the cavity image does not meet the optimized printing conditions.

[0122] Specifically, when the above ratio is less than the preset ratio threshold, it means that the printing time of the cavity area is shorter and the printing time of the current slice as a whole is longer than the printing time of the cavity area. Therefore, during the overall printing time, the liquid in contact with the closed cavity can flow fully, and the liquid remains relatively still when printing the cavity area. At this time, there is no need to adjust the printing strategy specifically for the closed cavity, and the problems that may occur when printing the closed cavity can be avoided.

[0123] This embodiment determines that the cavity image does not meet the optimized printing conditions when the ratio of the closed cavity area to the cross-sectional area of ​​the cavity image is small. Then, it prints model slices according to the conventional printing method. This simplifies some printing methods for closed cavities based on the actual structure of the printed part, thereby helping to improve printing efficiency.

[0124] In some optional implementations of this embodiment, such as Figure 11 As shown, step 50322 includes:

[0125] Step 503221: Determine the cavity degree value of the cavity image based on the cross-sectional geometric information of the cavity image.

[0126] The cross-sectional geometric information may include, but is not limited to, at least one of the following parameters: the area, location, shape, and wall thickness of the cavity. For example... Figure 12As shown, the area, location, shape, and wall thickness of cavities may be the same or different in different slice layers; similarly, the area, location, shape, and wall thickness of cavities may also be the same or different in the same slice layer. Therefore, it is necessary to calculate the cavity severity value of the cavity image based on at least one of the following: cavity wall thickness, number of cavities, cavity area, cavity shape, and influencing factors between cavities, according to the cross-sectional geometric information of the cavity image. This cavity severity value is then used to determine the printing difficulty value and to schedule appropriate printing strategies. Typically, a weight can be set for each parameter, and the parameters can be summed to obtain the cavity severity value. The rules followed in calculating the cavity severity value may include: the larger the cavity area, the larger the cavity severity value; the smaller the minimum wall thickness of the cavity, the larger the cavity severity value; and the closer the cavity is to other cross-sections, the larger the cavity severity value.

[0127] Step 503222: Obtain the material parameters of the printing material for the 3D model.

[0128] The material parameters may include, but are not limited to, at least one of the following: viscosity, hardness, tensile strength, flexural strength, etc.

[0129] Step 503223: Based on the cavity degree value and material parameters, determine the cavity printing difficulty value of the cavity image.

[0130] Specifically, different weights can be set for different material parameters, as well as a weight for the cavity degree value. A weighted sum of the material parameters and the cavity degree value is then performed to obtain the cavity printing difficulty value. For example, the higher the viscosity, the lower the hardness, the lower the tensile strength, and the lower the flexural strength of the printing material, the higher the calculated cavity difficulty value.

[0131] This embodiment calculates the cavity printing difficulty value by comprehensively considering material parameters and cavity degree values, thereby obtaining data from more aspects to reflect the magnitude of cavity printing difficulty. By combining printing material characteristics and structural features, a high-precision printing difficulty value is obtained, which helps to further adjust the printing method accurately according to the printing difficulty value and improve the printing quality of closed cavities.

[0132] In some optional implementations of this embodiment, step 503221 can be performed as follows:

[0133] Based on at least one of the cross-sectional geometric information of the cavity image, including cavity wall thickness, number of cavities, cavity area, cavity shape, and influence factors between cavities, calculate the cavity degree value of the cavity image.

[0134] The aforementioned cross-sectional geometric information includes all items that can be quantified. By setting the weight of each parameter, the degree of cavity can be calculated. The weights can be set according to the actual printing scenario, and the setting principles can follow these rules:

[0135] The cavity wall thickness mentioned above includes the minimum wall thickness of each cavity. The smaller the minimum wall thickness, the higher the cavity degree value. The more cavities mentioned above, the higher the cavity degree value. The larger the cavity area, the higher the cavity degree value.

[0136] The shape of a cavity can be represented by at least one of the following parameters: the size of the envelope rectangle of each cavity, the size of the minimum circumscribed circle, and the dispersion value of the cavity edge. These parameters representing the shape of a closed cavity can indicate the degree of deviation of the cross-sectional shape of the closed cavity from a predetermined shape (e.g., a circle). For example, the envelope rectangle and the minimum circumscribed circle can be used to describe the similarity between the cross-sectional shape of the closed cavity and the predetermined shape, respectively. The dispersion value can be used to indicate the deviation of a point on the edge of the closed cavity's cross-section from the center point of the cross-section; therefore, the dispersion value can be used to indicate whether the slice cross-section is a regular geometric shape. Figure 12 As shown, the area, location, shape, and wall thickness of cavities may be the same or different in different slice layers; similarly, the area, location, shape, and wall thickness of cavities may also be the same or different in the same slice layer. Therefore, it is necessary to calculate the cavity severity value of the cavity image based on at least one of the following: cavity wall thickness, number of cavities, cavity area, cavity shape, and influencing factors between cavities, according to the cross-sectional geometric information of the cavity image. This cavity severity value is then used to determine the printing difficulty value and to schedule appropriate printing strategies. Typically, each parameter can be multiplied by its corresponding coefficient and then summed to obtain a value representing the degree of deviation from the regular geometric shape; the larger this value, the higher the cavity severity value.

[0137] The influencing factors between cavities may include, but are not limited to, at least one of the following: the minimum distance between each closed cavity, the relative area ratio between each closed cavity, the proportion of the area of ​​the envelope rectangle of each closed cavity to the entire slice cross-section, and the proportion of the area of ​​the smallest circumscribed circle of each closed cavity to the entire slice cross-section. The larger the influencing factor, the higher the cavity degree value.

[0138] It should be understood that when the cavity image contains cross-sections of multiple closed cavities, the cavity degree value corresponding to each closed cavity can be calculated separately according to the above parameters and rules. Then, the cavity degree value corresponding to the cavity image can be calculated by weighted summation, averaging, etc.

[0139] This embodiment calculates the cavity degree value based on parameters from multiple dimensions of the cross-sectional geometry information, thereby making the calculated cavity degree value more accurately reflect the difficulty of printing a closed cavity and thus improving the quality of printing a closed cavity.

[0140] In some optional implementations of this embodiment, in the above... Figure 10Based on the corresponding embodiment, step 504 can be further performed as follows:

[0141] Based on the pre-defined correspondence between cavity printing strategies and cavity printing difficulty values, at least one cavity printing method corresponding to the cavity printing difficulty value of the cavity image is determined as the target cavity printing strategy from at least two cavity printing strategies included in the pre-defined cavity printing strategies.

[0142] In this case, each of the at least two cavity printing strategies can be obtained by setting different printing parameters. For example, the greater the cavity printing difficulty value, the longer the printed part can stay at the minimum distance from the bottom of the tray.

[0143] This embodiment sets up multiple cavity printing strategies and selects the target cavity printing strategy that corresponds to the calculated cavity printing difficulty value. This achieves adaptive adjustment of the printing strategy based on the structural characteristics of the current 3D model, so that the current target cavity printing strategy can better match the closed cavity structure of the current model slice, thereby further improving the printing quality of the model.

[0144] In some optional implementation strategies of this embodiment, the above-mentioned at least two cavity printing strategies include at least two of the following:

[0145] Method 1: When the liquid level of the printing material is lower than the preset height, control the liquid replenishment device to replenish the printing material to the tray so that the liquid level of the printing material is kept higher than the rising height of the forming platform.

[0146] The amount of printing material added to the tray can be set arbitrarily, as long as the liquid level of the printing material is kept higher than the rising height of the forming platform.

[0147] Method 2: When the forming platform descends, at a layer thickness that is a first preset multiple of the bottom of the material tray, the forming platform is controlled to stop moving. After waiting for a first preset time, the forming platform is controlled to continue descending to a layer thickness that is a second preset multiple of the bottom of the material tray, and the printing operation is started. The first preset multiple is greater than the second preset multiple.

[0148] Typically, the first preset multiplier can be set to any value within the range of 1x layer thickness to 10x layer thickness. Specifically, it can be 1x, 1.5x, 2x, 2.5x, 3x, 3.5x, 4x, 4.5x, 5x, 5.5x, 6x, 6.5x, 7x, 7.5x, 8x, 8.5x, 9x, 9.5x, 10x, and ranges between these values. The second preset multiplier can be set to 1x layer thickness, and the first preset duration can be set to any value within the range of 0.5 seconds to 10 seconds. The printing time can be 0.5 seconds, 1 second, 1.5 seconds, 2 seconds, 2.5 seconds, 3 seconds, 3.5 seconds, 4 seconds, 4.5 seconds, 5 seconds, 5.5 seconds, 6 seconds, 6.5 seconds, 7 seconds, 7.5 seconds, 8 seconds, 8.5 seconds, 9 seconds, 9.5 seconds, 10 seconds, and the range between these values. That is, the forming platform descends to a greater distance from the bottom of the material tray, allowing the liquid to flow out quickly from the bottom of the printed part. After waiting for a period of time, it descends again to 1 layer thickness, and then the layer slice is printed according to the normal printing process.

[0149] Method 3: When the forming platform descends to a layer thickness that is a third preset multiple from the bottom of the material tray, control the forming platform to stop moving, wait for a second preset time, and then control the forming platform to rise to a layer thickness that is a second preset multiple from the bottom of the material tray to start the printing operation. The third preset multiple is less than the second preset multiple.

[0150] Typically, the third preset multiplier can be set to any value within the range of 0.1 times the layer thickness to 0.9 times the layer thickness. Specifically, it can be 0.1 times, 0.2 times, 0.3 times, 0.4 times, 0.5 times, 0.6 times, 0.7 times, 0.8 times, 0.9 times, and the range between these values. The second preset duration can be set to a smaller value, for example, it can be set to 0. That is, when it descends to 0.1 times to 0.9 times the layer thickness from the bottom of the tray, it immediately rises to 1 times the layer thickness from the bottom of the tray, so that most of the liquid at the bottom of the printed part flows out to the surroundings. Then the forming platform is raised to offset the flow of liquid, and then the layer slice is printed according to the normal printing process.

[0151] Method 4: When the forming platform descends to a layer thickness that is a second preset multiple of the bottom of the material tray, control the forming platform to stop moving and wait for a third preset time before starting the printing operation.

[0152] Typically, the third preset duration can be set to any value within the range of 1 to 20 seconds. That is, when the forming platform descends to a distance of 1 layer thickness from the bottom of the material tray, a longer period of time is waited for the liquid at the bottom of the printed part to settle before printing the slice of that layer according to the normal printing process.

[0153] In some optional implementation strategies of this embodiment, the above-mentioned at least two cavity printing strategies include at least two of the following:

[0154] Method 5: When the forming platform descends, at a layer thickness that is a first preset multiple of the liquid surface at the top of the material tray, control the forming platform to stop moving, wait for a first preset time, and then control the forming platform to continue descending to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and start the printing operation. Here, the first preset multiple is less than the second preset multiple.

[0155] Method 6: When the forming platform descends to a layer thickness that is a third preset multiple of the liquid surface at the top of the material tray, control the forming platform to stop moving, wait for a second preset time, and then control the forming platform to rise to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and start the printing operation. The third preset multiple is greater than the second preset multiple.

[0156] The adjustment method can be referred to Method 2 and Method 3 of the previous embodiment, and will not be repeated here.

[0157] It should be noted that, except for methods two and three, and methods five and six which cannot be superimposed due to conflicts in the control methods of the forming platform, the remaining printing methods can be arbitrarily superimposed according to the cavity printing difficulty value. For example, when the cavity printing difficulty value is in the lower first interval, method one can be selected; when it is in the higher second interval, methods one and two can be selected; when it is in the higher third interval, methods one and three can be selected; and when it is in the higher fourth interval, methods one, two, and four can be selected, and so on. Top projection technology can be based on superimposed processing of methods one, four, five, and six.

[0158] It should also be noted that the preset duration, preset height, preset multiplier and other parameters mentioned above can be set according to various parameters such as the degree of cavity and material properties in the actual printing scenario. The duration, multiplier and other parameters listed in this embodiment are merely exemplary and do not constitute the protection scope limited by the embodiments of this application.

[0159] The six cavity printing methods provided in this embodiment allow for flexible selection of at least one cavity printing method when the cavity printing difficulty is high, further improving the operational accuracy when printing cavities and thus improving the printing quality.

[0160] In some optional implementations of this embodiment, step 5032 is further used for:

[0161] If the wall thickness of the closed cavity in the cavity image is greater than or equal to the preset wall thickness, the closed cavity wall in the cavity image is divided into a filling area and a contour area, and the filling area and the contour area are printed in sequence.

[0162] like Figure 13A As shown, it displays the original cavity image. Figure 13B The image of the split filled area is shown. Figure 13CThe image shows the split contour area. During printing, the fill area can be printed first to prevent the liquid inside the cavity from flowing outwards, and then the contour area can be printed to refine the area around the fill area, thus producing a smooth surface. It should be understood that... Figure 13B The filled area image shown is just an example. In actual printing, the pattern of the filled area can be set arbitrarily, such as solid pattern, grid pattern, honeycomb pattern, etc.

[0163] It should be noted that the printing method provided in this embodiment can be used alone or in any combination with the four cavity printing methods provided in the above embodiments, thereby further reducing the risk of residue generation when printing closed cavities and thus improving printing quality to a greater extent.

[0164] Figure 14 This application provides a three-dimensional model printing apparatus, applied to a 3D printing device, which includes a molding platform. Specifically, the apparatus includes: an acquisition module 1401 for acquiring three-dimensional model data; a first determination module 1402 for determining cavity data from the three-dimensional model data; and a printing module 1403 for scheduling a corresponding printing strategy based on the cavity data to perform printing. The printing strategy includes at least one of adjusting the liquid level, controlling the waiting time, controlling the discharge height, controlling the motion parameters of the molding platform, adjusting the exposure strategy, and adjusting the image data corresponding to the cavity.

[0165] In some optional implementations of this embodiment, the printing module includes: a first determining unit, used to determine the cavity part and non-cavity part of the three-dimensional model based on the cavity data; and a scheduling unit, used to schedule the corresponding cavity printing strategy for printing the cavity part and the corresponding non-cavity printing strategy for printing the non-cavity part.

[0166] In some optional implementations of this embodiment, the first determining module includes: a first identification unit, used to identify the entire three-dimensional model to obtain three-dimensional data, wherein the three-dimensional data includes at least one of the following: three-dimensional position information of the model, model shape, model volume, model wall thickness, and number of sub-models; determining cavity data from the three-dimensional data, wherein the cavity data includes at least one of the following: three-dimensional position information of cavities, cavity shape, cavity volume, cavity wall thickness, and number of cavities; and / or, a second identification unit, used to slice the three-dimensional model and identify the slices in which the cavities in the three-dimensional model are located as a cavity slice set; identifying each slice in the cavity slice set to obtain cavity data, wherein the cavity data includes at least one of the following: area, position, shape, wall thickness, and number of slice cross sections, and at least one of the following: area, position, shape, wall thickness, and number of cavities in the slice cross sections.

[0167] In some optional implementations of this embodiment, the second identification unit includes: a generation subunit, used to generate a two-dimensional slice image of each slice in the slice set, to obtain a two-dimensional slice image set; a first determination subunit, used to determine the cross-sectional geometric information of each two-dimensional slice image in the two-dimensional slice image set; and a second determination subunit, used to determine cavity data based on the cross-sectional geometric information.

[0168] In some optional implementations of this embodiment, the printing module includes: a second determining unit, configured to determine a subset of cavity images corresponding to the cavity region from a set of two-dimensional slice images based on cross-sectional geometric information; and a printing unit, configured to determine, for each cavity image in the cavity image subset, whether the cavity image meets the optimized printing conditions based on the cross-sectional geometric information of the cavity image; if the optimized printing conditions are met, to determine the target cavity printing strategy corresponding to the cavity image, and to print the three-dimensional model slice corresponding to the cavity image based on the target cavity printing strategy.

[0169] In some optional implementations of this embodiment, the second determining unit includes: a third determining subunit, configured to, for each two-dimensional slice image in the set of two-dimensional slice images, determine the difference between the cavity area in the two-dimensional slice image and the cavity area in the previous layer of two-dimensional slice image based on the cross-sectional geometric information of the two-dimensional slice image; if the difference meets the cavity determination condition and it is determined that the two-dimensional slice image contains a through hole, determine the size of the through hole; and a fourth determining subunit, configured to, if the size of the through hole is less than or equal to a preset size, determine that the two-dimensional slice image is a cavity image.

[0170] In some optional implementations of this embodiment, the printing unit includes: a fifth determining subunit, used to determine the ratio of the cavity area to the cross-sectional area of ​​the cavity image based on the cross-sectional geometric information of the cavity image; a sixth determining subunit, used to determine the cavity printing difficulty value of the cavity image based on the cross-sectional geometric information of the cavity image if the ratio is greater than or equal to a preset ratio threshold; and a seventh determining subunit, used to determine that the cavity image meets the optimized printing conditions if the cavity printing difficulty value is greater than or equal to a preset difficulty threshold.

[0171] In some optional implementations of this embodiment, the device further includes: a second determining module, used to determine that the cavity image does not meet the optimized printing conditions if the ratio is less than a preset ratio threshold.

[0172] In some optional implementations of this embodiment, the sixth determining subunit is further configured to: determine the cavity degree value of the cavity image based on the cross-sectional geometric information of the cavity image; obtain the material parameters of the printing material of the three-dimensional model; and determine the cavity printing difficulty value of the cavity image based on the cavity degree value and the material parameters.

[0173] In some optional implementations of this embodiment, the sixth determining subunit is further configured to: calculate the cavity degree value of the cavity image based on at least one of the cross-sectional geometric information of the cavity image, including cavity wall thickness, number of cavities, cavity area, cavity shape, and influence factors between cavities.

[0174] In some optional implementations of this embodiment, the printing unit is further configured to: based on the correspondence between a preset cavity printing strategy and a cavity printing difficulty value, determine at least one cavity printing strategy corresponding to the cavity printing difficulty value of the cavity image as the target cavity printing strategy from at least two cavity printing strategies included in the preset cavity printing strategy.

[0175] In some optional implementations of this embodiment, the 3D printing equipment also includes a material tray, and at least two cavity printing strategies include at least two of the following: Method 1: When the liquid level of the printing material is lower than a preset height, the liquid replenishment device is controlled to replenish the printing material to the material tray so that the liquid level of the printing material remains higher than the rising height of the forming platform; Method 2: When the forming platform descends, at a layer thickness of a first preset multiple from the bottom of the material tray, the forming platform is controlled to stop moving, waits for a first preset time, and then continues to descend to a layer thickness of a second preset multiple from the bottom of the material tray, and the printing operation is started, wherein the first preset multiple is greater than the second preset multiple; Method 3: When the forming platform descends to a layer thickness of a third preset multiple from the bottom of the material tray, the forming platform is controlled to stop moving, waits for a second preset time, and then rises to a layer thickness of a second preset multiple from the bottom of the material tray, and the printing operation is started, wherein the third preset multiple is less than the second preset multiple; Method 4: When the forming platform descends to a layer thickness of a second preset multiple from the bottom of the material tray, the forming platform is controlled to stop moving, waits for a third preset time, and then the printing operation is started.

[0176] In some optional implementations of this embodiment, at least two cavity printing strategies include at least two of the following: Method 5: When the forming platform descends, at a layer thickness that is a first preset multiple of the liquid surface at the top of the material tray, the forming platform is controlled to stop moving, and after waiting for a first preset time, the forming platform is controlled to continue descending to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and the printing operation is started, wherein the first preset multiple is less than the second preset multiple; Method 6: When the forming platform descends to a layer thickness that is a third preset multiple of the liquid surface at the top of the material tray, the forming platform is controlled to stop moving, and after waiting for a second preset time, the forming platform is controlled to rise to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and the printing operation is started, wherein the third preset multiple is greater than the second preset multiple.

[0177] In some optional implementations of this embodiment, the printing unit is further configured to: if the cavity wall thickness in the cavity image is greater than or equal to a preset wall thickness, divide the closed cavity wall in the cavity image into a filling area and a contour area, and print the filling area and the contour area in sequence.

[0178] The 3D model printing device provided in this embodiment can be as follows: Figure 14 The 3D model printing device shown can execute all the steps of the above 3D model printing methods, thereby achieving the technical effects of the above 3D model printing methods. For details, please refer to the relevant descriptions above. For the sake of brevity, it will not be elaborated here.

[0179] Figure 15 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 15 The illustrated electronic device 1500 includes at least one processor 1501, a memory 1502, at least one network interface 1504, and other user interfaces 1503. The various components in the electronic device 1500 are coupled together via a bus system 1505. It is understood that the bus system 1505 is used to implement communication between these components. In addition to a data bus, the bus system 1505 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in… Figure 11 The general labeled all buses as Bus System 1505.

[0180] The user interface 1503 may include a display, keyboard, or clicking device (e.g., mouse, trackball, touchpad, or touchscreen).

[0181] It is understood that the memory 1502 in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous DRAM (SDRAM), Double Data Rate Synchronous DRAM (DDRSDRAM), Enhanced Synchronous DRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memory 1502 described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0182] In some implementations, memory 1502 stores elements, executable units or data structures, or subsets thereof, or extended sets thereof: operating system 15021 and application program 15022.

[0183] The operating system 15021 includes various system programs, such as the framework layer, core library layer, and driver layer, used to implement various basic business functions and handle hardware-based tasks. The application program 15022 includes various applications, such as a media player and a browser, used to implement various application functions. Programs implementing the methods of this application embodiment can be included in application program 15022.

[0184] In this embodiment, by calling the program or instructions stored in memory 1502, specifically the program or instructions stored in application program 15022, processor 1501 executes the method steps provided in each method embodiment, including, for example:

[0185] Acquire 3D model data; determine cavity data from the 3D model data; schedule the corresponding printing strategy according to the cavity data for printing; wherein the printing strategy includes at least one of adjusting liquid level, controlling waiting time, controlling drainage height, controlling molding platform motion parameters, adjusting exposure strategy, and adjusting image data corresponding to the cavity.

[0186] The methods disclosed in the embodiments of this application can be applied to or implemented by the processor 1501. The processor 1501 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware or by instructions in the form of software in the processor 1501. The processor 1501 may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or can be executed by a combination of hardware and software units in the decoding processor. The software units may be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 1502. Processor 1501 reads the information in memory 1502 and, in conjunction with its hardware, completes the steps of the above method.

[0187] It is understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, microcode, or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described above in this application, or combinations thereof.

[0188] For software implementation, the techniques described herein can be implemented by units that perform the functions described above. The software code can be stored in memory and executed by a processor. The memory can be implemented within the processor or external to the processor.

[0189] The electronic device provided in this embodiment may be as follows: Figure 15 The electronic device shown can execute all the steps of the three-dimensional model printing methods described above, thereby achieving the technical effects of the three-dimensional model printing methods described above. For details, please refer to the relevant descriptions above. For the sake of brevity, it will not be elaborated here.

[0190] This application also provides a storage medium (computer-readable storage medium). This storage medium stores one or more programs. The storage medium may include volatile memory, such as random access memory; it may also include non-volatile memory, such as read-only memory, flash memory, hard disk, or solid-state drive; and it may also include combinations of the above types of memory.

[0191] One or more programs in the storage medium can be executed by one or more processors to implement the above-described three-dimensional model printing method executed on the electronic device side.

[0192] The processor described above is used to execute programs stored in memory to implement the following steps of a 3D model printing method executed on the electronic device side:

[0193] Acquire 3D model data; determine cavity data from the 3D model data; schedule the corresponding printing strategy according to the cavity data for printing; wherein the printing strategy includes at least one of adjusting liquid level, controlling waiting time, controlling drainage height, controlling molding platform motion parameters, adjusting exposure strategy, and adjusting image data corresponding to the cavity.

[0194] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different circuits to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0195] The steps of the circuits or algorithms described in connection with the embodiments disclosed herein can be implemented in hardware, software modules executed by a processor, or a combination of both. The software modules can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the art.

[0196] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also mean including the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The circuit steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of execution is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0197] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for printing a three-dimensional model, applied to a 3D printing device, the 3D printing device comprising a forming platform, characterized in that, The method includes: Obtain 3D model data; Determining cavity data from the three-dimensional model data includes: - Slice the 3D model to obtain a predetermined slice; determine the cross-sectional geometry of the predetermined slice; based on the cross-sectional geometry of the predetermined slice, determine whether the predetermined slice meets the optimized printing conditions; if it meets the optimized printing conditions, determine the target cavity printing strategy for the predetermined slice. Based on the cavity data, the target cavity printing strategy is scheduled for printing; wherein, the target cavity printing strategy includes at least one of adjusting the liquid level, controlling the waiting time, controlling the liquid discharge height, controlling the motion parameters of the molding platform, and adjusting the image data corresponding to the cavity; The optimized printing conditions include any one of the following: - The ratio of the cavity area to the cross-sectional area of ​​the predetermined slice is greater than or equal to a preset ratio threshold, and the cavity printing difficulty value determined based on the cross-sectional geometry information of the predetermined slice is greater than or equal to a preset difficulty threshold. - The cavity area of ​​the cavity image of the predetermined slice is greater than the preset area; - The cavity wall thickness of the cavity image of the predetermined slice is less than the preset wall thickness; Furthermore, the image data corresponding to the adjusted cavity includes: - When the cavity wall thickness of the cavity image of the predetermined slice is greater than or equal to the predetermined wall thickness, the cavity wall in the cavity image is split into a filling area and a contour area for sequential printing of the filling area and the contour area.

2. The method according to claim 1, characterized in that, Based on the cavity data, the target cavity printing strategy is scheduled for printing, including: Based on the cavity data, the cavity and non-cavity parts of the three-dimensional model are determined; For the cavity portion, the corresponding cavity printing strategy is scheduled for printing; for the non-cavity portion, the corresponding non-cavity printing strategy is scheduled for printing.

3. The method according to claim 1, characterized in that, Determining cavity data from the three-dimensional model data includes: The entire 3D model is identified to obtain 3D data, wherein the 3D data includes at least one of the following: 3D position information of the model, model shape, model volume, model wall thickness, and number of sub-models; from the 3D data, cavity data is determined, wherein the cavity data includes at least one of the following: 3D position information of the cavity, cavity shape, cavity volume, cavity wall thickness, and number of cavities; and / or, The three-dimensional model is sliced, and the slices containing cavities in the three-dimensional model are identified as a cavity slice set; each slice in the cavity slice set is identified to obtain the cavity data, wherein the cavity data includes at least one of the following: the area, position, shape, wall thickness, and number of the slice cross section, and at least one of the following: the area, position, shape, wall thickness, and number of cavities in the slice cross section.

4. The method according to claim 3, characterized in that, Each slice in the cavity slice set is identified to obtain the cavity data, including: Generate a two-dimensional slice image for each slice in the slice set to obtain a two-dimensional slice image set; Determine the cross-sectional geometric information of each two-dimensional slice image in the set of two-dimensional slice images; Based on the cross-sectional geometric information, the cavity data is determined.

5. The method according to claim 4, characterized in that, Based on the cavity data, the target cavity printing strategy is scheduled for printing, including: Based on the cross-sectional geometric information, a subset of cavity images corresponding to the cavity region is determined from the set of two-dimensional slice images; For each cavity image in the cavity image subset, based on the cross-sectional geometry information of the cavity image, it is determined whether the cavity image meets the optimized printing conditions; if it meets the optimized printing conditions, the target cavity printing strategy corresponding to the cavity image is determined, and based on the target cavity printing strategy, the three-dimensional model slice corresponding to the cavity image is printed.

6. The method according to claim 5, characterized in that, Based on the cross-sectional geometric information, a subset of cavity images corresponding to the cavity region is determined from the set of two-dimensional slice images, including: For each two-dimensional slice image in the set of two-dimensional slice images, based on the cross-sectional geometric information of the two-dimensional slice image, the difference between the cavity area in the two-dimensional slice image and the cavity area in the previous layer of two-dimensional slice image is determined; if the difference meets the cavity determination condition and it is determined that the two-dimensional slice image contains a through hole, the size of the through hole is determined. If the size of the through hole is less than or equal to the preset size, the two-dimensional slice image is determined to be a cavity image.

7. The method according to claim 1, characterized in that, The method further includes: If the ratio is less than a preset ratio threshold, the cavity image is determined to not meet the optimized printing conditions.

8. The method according to claim 1, characterized in that, The cavity printing difficulty value is determined according to the following steps: Based on the cross-sectional geometry information of the predetermined slice, the cavity degree value of the predetermined slice is determined; Obtain the material parameters of the printing material for the 3D model; Based on the cavity degree value and the material parameters, the cavity printing difficulty value of the predetermined slice is determined.

9. The method according to claim 8, characterized in that, Based on the cross-sectional geometry information of the predetermined slice, the cavity degree value of the predetermined slice is determined, including: Based on at least one of the cross-sectional geometric information of the predetermined slice, including cavity wall thickness, number of cavities, cavity area, cavity shape, and influence factors between cavities, the cavity degree value of the predetermined slice is calculated.

10. The method according to claim 5, characterized in that, Determine the target cavity printing strategy corresponding to the cavity image, including: Based on the pre-defined correspondence between cavity printing strategies and cavity printing difficulty values, at least one cavity printing strategy corresponding to the cavity printing difficulty value of the cavity image is determined from at least two cavity printing strategies included in the pre-defined cavity printing strategies as the target cavity printing strategy.

11. The method according to claim 10, characterized in that, The 3D printing equipment also includes a material tray, and the at least two cavity printing strategies include at least two of the following: Method 1: When the liquid level of the printing material is lower than the preset height, the liquid replenishment device is controlled to replenish the printing material to the tray so that the liquid level of the printing material is kept higher than the rising height of the forming platform; Method 2: When the forming platform descends, at a layer thickness that is a first preset multiple of the bottom of the material tray, the forming platform is controlled to stop moving. After waiting for a first preset time, the forming platform is controlled to continue descending to a layer thickness that is a second preset multiple of the bottom of the material tray, and the printing operation is started. The first preset multiple is greater than the second preset multiple. Method 3: When the forming platform descends to a layer thickness that is a third preset multiple of the bottom of the material tray, the forming platform is controlled to stop moving. After waiting for a second preset time, the forming platform is controlled to rise to a layer thickness that is a second preset multiple of the bottom of the material tray, and the printing operation is started. The third preset multiple is less than the second preset multiple. Method 4: When the forming platform descends to a layer thickness that is a second preset multiple of the bottom of the material tray, the forming platform is controlled to stop moving, and the printing operation is started after a third preset time.

12. The method according to claim 10, characterized in that, The 3D printing equipment also includes a material tray, and the at least two cavity printing strategies include the following two: Method 5: When the forming platform descends, at a layer thickness that is a first preset multiple of the liquid surface at the top of the material tray, the forming platform is controlled to stop moving. After waiting for a first preset time, the forming platform is controlled to continue descending to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and the printing operation is started. Here, the first preset multiple is less than the second preset multiple. Method 6: When the forming platform descends to a layer thickness that is a third preset multiple of the liquid surface at the top of the material tray, the forming platform is controlled to stop moving. After waiting for a second preset time, the forming platform is controlled to rise to a layer thickness that is a second preset multiple of the liquid surface at the top of the material tray, and the printing operation is started. The third preset multiple is greater than the second preset multiple.

13. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor is configured to execute a computer program stored in the memory, wherein when the computer program is executed, it implements the three-dimensional model printing method according to any one of claims 1-12.

14. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the three-dimensional model printing method according to any one of claims 1-12.

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