3D fused deposition modeling of complex models

Abstract

This invention discloses a three-dimensional fused deposition modeling method for complex models, which includes creating a three-dimensional model of the complex model, obtaining UV lines on the layer transition surfaces of the complex model based on the three-dimensional model, determining specific positions on the layer transition surfaces, determining V lines corresponding to specific positions on the UV lines, printing the complex model based on the print trajectory, and designating multiple points on the V lines as layer transition points in the print trajectory of the complex model.

Description

Technical Field

[0001] The present application claims priority to the Chinese patent application with application number 202311699990.8 filed with the China National Intellectual Property Administration on December 12, 2023, and the entire content of said application is incorporated herein by reference.

[0002] The present application relates to the technical field of building construction, for example, to three-dimensional fused deposition modeling of complex models. Background Art

[0003] Fused Deposition Modeling (FDM) technology is one type of 3D printing technology. Its principle is that after a thermoplastic material (for example, Acrylonitrile Butadiene Styrene (ABS), Poly Lactic Acid (PLA), etc.) is thermally melted by a high-temperature extrusion nozzle, the nozzle moves along the path recorded in the file data and simultaneously extrudes the material at a constant speed. After the extruded material solidifies on the printer platform, it forms one "layer" of the model; each time one layer is completed, the nozzle rises by a certain height, and this process continues to form the next layer until the printing of the model is completed.

[0004] The layer switching point of a 3D printing trajectory refers to the end point of the printing trajectory of each layer and the start point of the printing trajectory of the next layer set during trajectory planning. There are currently two commonly used planning methods for trajectory layer switching points: the first is to take a certain point on the printing trajectory line closest to the set point as the trajectory layer switching point, and the second is to take the break point of the curve of the printing trajectory of the current layer as the trajectory layer switching point.

[0005] In the case of complex models, the irregular shape of the model can cause the layer transition points to appear on the front of the model, resulting in visible protrusions at the layer transition points after printing is complete. This leads to defects in the appearance of the front of complex models. Furthermore, the layer transition point planning methods in related technologies cannot control the position of the layer transition points for irregular models. As a result, the material is at risk of warping and cracking due to its fragility at the connection points of the layer transitions, affecting the molding quality of the model.

[0006] Therefore, a three-dimensional fused deposition modeling method for complex models is urgently needed to solve the above problems. [Overview of the project] [Problems that the invention aims to solve]

[0007] This invention provides a three-dimensional fused deposition modeling method for complex models that allows for more flexible setting of layer transition points, minimizes appearance defects, and reduces the risk of warping and cracking as much as possible. [Means for solving the problem]

[0008] This application proposes the following technical solutions.

[0009] Creating a 3D model of a complex model, Obtaining UV lines from layer transition surfaces of complex models based on a 3D model, This includes determining specific positions on the layer transition plane, determining V lines corresponding to specific positions on the UV lines, printing a complex model based on the print trajectory, using multiple points on the V lines of the layer transition plane of the complex model as layer transition points in the print trajectory of the complex model, and ensuring that the multiple layer transition points correspond one-to-one with multiple slices of the complex model. This provides a three-dimensional fused deposition modeling method for complex models.

[0010] Before printing a complex model based on the print path, The complex model and V-lines are input into the slicing module, the complex model is divided into multiple slices, the V-lines are divided into multiple segments, and each segment's V-line corresponds to at least one slice. This further includes determining a point in the V-line segment corresponding to each slice based on the slice height of each slice, and obtaining the layer switching point for each slice.

[0011] The complex model includes an outer contour, and the outer contour forms multiple first contour lines that are sequentially stacked along the extension direction of the V-line after slicing the complex model, and each of the multiple first contour lines corresponds to one of the multiple slices of the complex model. Before printing a complex model based on the print path, the process further includes printing the outer contour corresponding to each slice, with the first contour line corresponding to each slice serving as the print path for the outer contour corresponding to each slice. Obtaining the layer switching point for each slice is possible. This includes defining the intersection of the first contour line corresponding to each slice and the V line as the layer switching point of the outer contour of each slice.

[0012] The complex model further comprises an internal grid provided within the outer contour, the internal grid including a plurality of second contour lines formed after slicing the complex model and sequentially stacked along the extending direction of the V lines, each of the plurality of second contour lines corresponding one-to-one with each of the plurality of first contour lines, and each of the plurality of second contour lines corresponding to each of the plurality of slices of the complex model. Before printing a complex model based on the print trajectory, the process further includes printing the internal grid corresponding to each slice, with the second contour line corresponding to each slice serving as the print trajectory for the internal grid corresponding to each slice. Obtaining the layer switching point for each slice is possible. This includes defining the intersection of the second contour line and the V line of the internal grid corresponding to each slice as the layer switching point of the internal grid corresponding to each slice.

[0013] After dividing a complex model into multiple slices, For each slice, a cutting circle is created centered on the layer switching point in the first contour line, the cutting circle intersects the second contour line at least partially, the first and second contour lines within the cutting circle are removed, and the print start and end points of the first contour line and the print start and end points of the second contour line are formed. The print endpoint of the first contour of the nth layer, the print start point of the second contour of the nth layer, the print endpoint of the second contour of the nth layer, and the print start point of the first contour of the (n+1)th layer are joined together at the layer transition point of the first contour of the (n+1)th layer, wherein the layer transition point of the first contour of the (n+1)th layer is the layer transition point between the print trajectory of the nth layer of the complex model and the print trajectory of the (n+1)th layer, and this is continued until the print trajectories of all slices of the complex model are obtained, and all slices of the complex model are printed, where n ≥ 1, and the print trajectory of each slice includes the print trajectory of the outer contour corresponding to each slice and the print trajectory of the inner grid corresponding to each slice.

[0014] A complex model includes multiple model segments, and printing a complex model is difficult. This involves printing multiple model segments individually, joining the printed model segments together, and forming a complex model.

[0015] The V-line of each model segment is used as an alignment line when joining two adjacent model segments of that model segment.

[0016] UV lines are obtained based on the UV map axes of a complex model.

[0017] The V-line is located on the unused surface of the complex model.

[0018] Unused surfaces include the bottom or back of complex models. [Brief explanation of the drawing]

[0019] [Figure 1]It is a flowchart of a three-dimensional hot melt additive manufacturing method for a complex model according to an exemplary embodiment of the present application. [Figure 2] It is a first structural schematic diagram of a complex model according to an exemplary embodiment of the present application. [Figure 3] It is a second structural schematic diagram of a complex model according to an exemplary embodiment of the present application. [Figure 4] It is a third structural schematic diagram of a complex model according to an exemplary embodiment of the present application. [Figure 5] It is a structural schematic diagram of a model segment of a complex model according to an exemplary embodiment of the present application. [Figure 6] It is a diagram of a first step of acquiring a print trajectory of a complex model according to an exemplary embodiment of the present application. [Figure 7] It is a diagram of a second step of acquiring a print trajectory of a complex model according to an exemplary embodiment of the present application. [Figure 8] It is a diagram of a third step of acquiring a print trajectory of a complex model according to an exemplary embodiment of the present application. Description of Reference Numerals

[0020] 1 Model segment 2 V-line 3 Layer switching point 4 Cutting circle 11 Outer contour 12 Internal grid 111 First contour line 121 Second contour line Mode for Carrying Out the Invention

[0021] Furthermore, in the description of this application, the directions or positional relationships indicated by terms such as "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the directions or positional relationships shown in the drawings and are merely for the purpose of simplifying and facilitating the description of this application. They do not indicate or imply that the device or element being referred to necessarily has a specific direction or must be constructed and operated in a specific direction, and therefore should not be understood as limiting this application. In addition, terms such as "first" and "second" are merely for explanatory purposes and should not be understood as indicating or implying relative importance. Here, the terms "first position" and "second position" refer to two different positions.

[0022] In this description, unless otherwise specified or limited, the terms “attachment,” “connection,” and “connection” should be interpreted broadly. For example, these may be fixed connections, detachable connections, mechanical connections, electrical connections, direct connections, indirect connections via an intermediate medium, or internal communication between two elements. A person skilled in the art will be able to understand the specific meaning of these terms in this application depending on the specific circumstances.

[0023] As shown in Figure 1, this embodiment provides a three-dimensional fused deposition modeling method for complex models, and includes the following steps.

[0024] In S1, a 3D model of a complex model is created.

[0025] In S2, during the process of creating a 3D model, UV lines are obtained for the layer transition surfaces of the complex model.

[0026] In S3, a specific position is determined on the layer transition surface, a V line corresponding to a specific position on the UV line is determined, and a complex model is printed based on the print trajectory. Here, multiple points on the V line 2 of the layer transition surface of the complex model are defined as layer transition points 3 of the print trajectory of the complex model, and these multiple layer transition points 3 correspond one-to-one to multiple layers of the complex model.

[0027] Here, in step S2, the layer transition surface is the surface where multiple layer transition points 3 are located after the complex model has been formed. If it is desired that the layer transition points 3 be located on the back of the complex model, a V line corresponding to a specific U position on the back of the complex model is obtained. In the three-dimensional fused deposition modeling method for complex models according to this embodiment, the points on the V line 2 in the UV line of the layer transition surface of the complex model are used as layer transition points 3 during 3D printing. As a result, all layer transition points 3 of each layer of the printed complex model are located on the V line 2, meaning that multiple layer transition points 3 form a continuous line. This improves the appearance quality after the complex model has been formed and avoids the situation where there are many appearance defects due to inconsistencies in layer transition points 3 during the printing process of large components such as complex models. Furthermore, by using the point on line V2 as the layer transition point 3, the selection of the layer transition point 3 becomes more free and flexible. In particular, in the case of irregularly shaped and complex models, this three-dimensional fused deposition modeling method can ensure the appearance molding quality of complex models, minimize warping and cracking of the material due to weak points at the location of the layer transition point 3, and increase the structural strength of complex models after molding.

[0028] In this embodiment, referring to Figures 2 and 3, a complex model includes multiple model segments 1, each model segment 1 is printed individually, and the multiple printed model segments 1 are joined together to form the complex model. In the case of large components, it is difficult to achieve this in a single print molding, so the complex model can be divided into multiple model segments 1, and each model segment 1 can be printed individually, reducing the difficulty of printing, which is advantageous for subsequent transportation and improves ease of installation.

[0029] Printing complex models is This involves printing multiple model segments individually, joining the printed model segments together, and forming a complex model.

[0030] The V-lines 2 of each model segment 1 are used as alignment lines when joining two adjacent model segments 1. That is, after 3D printing is complete, the V-lines 2 formed at multiple layer transition points 3 on each model segment 1 can be used as positioning lines when joining the model segments 1. As shown in Figures 4 and 5, the ends of the V-lines 2 of two adjacent model segments 1 face each other, and this arrangement is advantageous for subsequent joining and assembly operations, prevents misalignment of the joints, and further improves the appearance quality of complex models after molding.

[0031] In step S2, UV lines are obtained based on the UV map axes of the complex model. The UV map axes refer to the UV map axes corresponding to the 2D mapping of a 3D model, where U is horizontal and V is vertical. The UV map axes are coordinate mapping axes that extend a 3D model into 2D, introduced to make one 2D texture map correspond to one 3D model.

[0032] In step S3, line V2 is located on the unused surface of the complex model. That is, the layer transition surface may be the unused surface of the complex model. With this placement, after printing, the seam that appears at the layer transition point 3 can be hidden on the unused surface of the complex model, without affecting the smoothness of the usable surface of the complex model and ensuring appearance quality.

[0033] Unused surfaces include the bottom or back of complex models. Exemplarily, as shown in Figures 2, 3, and 4, the complex model is a model of a landscape bench in a construction project, where line V2 is on the bottom of the landscape bench model, allowing the seams after printing to be completely hidden on the bottom of the landscape bench. After the landscape bench is installed, the seams are not visible from the outside, resulting in a better appearance.

[0034] Referring to Figure 1, the following steps are further included before printing a complex model based on the print trajectory.

[0035] In S301, the model is sliced, and the complex model and its corresponding V-line 2 are input to the slicing program (slicing module). The complex model is divided into multiple slices, and the V-line 2 is divided into multiple segments. Each segment's V-line corresponds to at least one slice, and the corresponding point in the V-line 2 is obtained from the V-line 2 of each segment based on the slice height of each slice of the complex model, thereby obtaining the layer switching points 3 for each layer of the complex model. The slicing module is a related technology and is configured to divide the created 3D model into multiple slices.

[0036] In this embodiment, referring to Figures 5, 7, and 8, the complex model includes an outer contour 11, which forms a plurality of first contour lines 111 formed by sequentially stacking the complex model along the extending direction of the V line 2 after slicing the complex model. The plurality of first contour lines 111 correspond to multiple layers of the complex model, and the intersection of each first contour line 111 and the V line 2 is the layer switching point 3 of the corresponding layer of the complex model. The first contour lines 111 are the print trajectory of the outer contour 11. The shape of the outer contour 11 is the outer shape of the complex model, and the number of first contour lines 111 is the number of layers of the complex model during printing.

[0037] The three-dimensional fused deposition modeling method for complex models according to this embodiment further includes printing the outer contours corresponding to each slice, using a first contour line corresponding to each slice as the print trajectory of the outer contour corresponding to each slice, before printing the complex model based on the print trajectory.

[0038] Obtaining the layer switching point for each slice is possible. This includes defining the intersection of the first contour line corresponding to each slice and the V line as the layer switching point of the outer contour of each slice.

[0039] The complex model further comprises an internal grid 12 provided within the outer contour 11, the internal grid 12 including a plurality of second contour lines 121 formed after slicing the complex model and sequentially stacked along the extending direction of the V line 2, the plurality of second contour lines 121 correspond one-to-one with a plurality of first contour lines 111, the plurality of second contour lines 121 correspond to a plurality of slices of the complex model, and the second contour lines 121 are the print trajectories of the internal grid 12. The internal grid 12 is used to increase the structural strength of the complex model and to give the molded model a certain load-bearing capacity.

[0040] The three-dimensional fused deposition modeling method for complex models according to this embodiment further includes printing the internal grid corresponding to each slice, using the second contour line corresponding to each slice as the print trajectory of the internal grid corresponding to each slice, before printing the complex model based on the print trajectory.

[0041] Obtaining the layer switching point for each slice is possible. This includes defining the intersection of the second contour line and the V line of the internal grid corresponding to each slice as the layer switching point of the internal grid corresponding to each slice.

[0042] Referring to Figures 1, 6, 7, and 8, the following steps are further included after step S301.

[0043] In S302, the print trajectory of the complex model is obtained, and for each slice, a cutting circle 4 is created centered on the layer switching point 3 in the first contour line 111. The cutting circle 4 intersects the second contour line 121 at least partially, and the first contour line 111 and the second contour line 121 within the cutting circle 4 are removed, forming the print start and end points of the first contour line 111 and the print start and end points of the second contour line 121.

[0044] The print endpoint of the first contour line 111 of the nth layer, the print start point of the second contour line 121 of the nth layer, the print endpoint of the second contour line 121 of the nth layer, and the print start point of the first contour line 111 of the (n+1)th layer are joined together at the layer transition point 3 of the first contour line 111 of the (n+1)th layer, and this point is the layer transition point 3 between the print trajectory of the nth layer and the print trajectory of the (n+1)th layer of the complex model, and this is continued until the print trajectories of all layers of the complex model are obtained, printing all slices of the complex model, where n ≥ 1. The print trajectory of each slice includes the print trajectory of the outer contour corresponding to each slice and the print trajectory of the inner grid corresponding to each slice. The print trajectories of multiple layers form the entire complete continuous print trajectory of the complex model by connecting the corresponding multiple layer transition points 3.

[0045] As shown in Figure 6, a cutting circle 4 is created at the position corresponding to the layer switching point 3 in each first contour line 111. After removing the first contour line 111 and the second contour line 121 within the cutting circle 4, as shown in Figure 7, each first contour line 111 and the second contour line 121 becomes an open trajectory line. By sequentially connecting the first contour line 111 of the outer contour 11 and the second contour line 121 of the inner grid 12 layer by layer, a continuous layer switching trajectory of a complex model can be formed.

[0046] As shown in Figure 8, assuming that the bottommost first contour line 111 in Figure 8 is the first layer, the print starting point of the first contour line 111 of the first layer is the print starting point of the entire complex model (i.e., the layer switching point of the first layer). From this point, the print jet head moves along the trajectory of the first contour line 111 of the first layer to the print ending point of the first contour line 111 of the first layer and the print starting point of the second contour line 121 of the first layer (the print ending point of the first contour line 111 and the print starting point of the second contour line 121 are the same point), and continues to move along the trajectory of the second contour line 121 of the first layer to the print ending point of the second contour line 121 of the first layer. This point is the print starting point of the first contour line 111 of the second layer, and is also the layer switching point 3 between the first and second layers of the complex model.

[0047] From the layer transition point 3 between the first and second layers, the print jet head moves along the trajectory of the first contour line 111 of the second layer to the print endpoint of the first contour line 111 of the second layer and the print start point of the second contour line 121 of the second layer (the print endpoint of the first contour line 111 and the print start point of the second contour line 121 are the same point), and continues to move along the trajectory of the second contour line 121 of the second layer to the print endpoint of the second contour line 121 of the second layer, which is the print start point of the first contour line 111 of the third layer, and is also the layer transition point 3 between the second and third layers of the complex model. This process is continued until the printing of the complex model is complete.

[0048] The three-dimensional fused deposition modeling method for complex models in the embodiment of the present invention can be performed by a three-dimensional fused deposition modeling apparatus for complex models. In the three-dimensional fused deposition modeling method for complex models according to this embodiment, modeling software creates a three-dimensional model of the complex model, UV mapping software obtains UV lines on the layer transition surfaces of the complex model based on the three-dimensional model, a slicing module determines a specific position U on the layer transition surface and determines a V line corresponding to that specific position U in the UV line, and a 3D printing device prints the complex model based on the print trajectory.

[0049] This application further proposes a three-dimensional fused deposition modeling apparatus for complex models, comprising memory, a processor, and 3D printing equipment.

[0050] When a computer program is stored in memory and the processor executes the computer program, Steps to create a 3D model of a complex model, In the process of creating a 3D model, the step of obtaining UV lines from the layer transition surfaces of a complex model is realized.

[0051] 3D printing equipment prints complex models by using multiple points on the V-line of the layer transition surface as layer transition points in the print trajectory of the complex model.

[0052] A three-dimensional fused deposition modeling apparatus for complex models may further include assembly equipment, which is configured to join multiple model segments after printing based on a joining method to form a complex model.

[0053] Here, assembly equipment may include virtual reality (VR) and augmented reality (AR) equipment, laser measuring instruments, jigs and fixing devices, or robots, etc.

Claims

1. Creating a 3D model of a complex model, Based on the three-dimensional model, UV lines are obtained for the layer switching surfaces of the complex model. This includes determining a specific position on the layer switching surface, determining a V-line corresponding to the specific position on the UV line, printing the complex model based on the print trajectory, setting multiple points on the V-line as layer switching points on the print trajectory of the complex model, and ensuring that the multiple layer switching points correspond one-to-one with multiple slices of the complex model. Three-dimensional fused deposition modeling (FDM) for complex models.

2. Before printing the complex model based on the aforementioned print trajectory, The complex model and the V-line are input into a slicing module, the complex model is divided into multiple slices, the V-line is divided into multiple segments, and the V-line of each segment corresponds to at least one slice. The process further includes determining a point in the V-line segment corresponding to each slice based on the slice height of each slice, and obtaining the layer switching point for each slice. A three-dimensional fused deposition modeling method for a complex model as described in claim 1.

3. The complex model includes an outer contour, and the outer contour forms a plurality of first contour lines that are sequentially stacked along the extending direction of the V-line after slicing the complex model, and each of the plurality of first contour lines corresponds to a plurality of slices of the complex model. Before printing the complex model based on the print trajectory, the method further includes printing the outer contour corresponding to each slice, using the first contour line corresponding to each slice as the print trajectory of the outer contour corresponding to each slice, Obtaining the layer switching point for each of the aforementioned slices is: This includes setting the intersection of the first contour line corresponding to each slice and the V line as the layer switching point of the outer contour of each slice. A three-dimensional fused deposition modeling method for complex models as described in claim 2.

4. The complex model further comprises an internal grid provided within the outer contour, the internal grid forming a plurality of second contour lines formed by sequentially stacking the complex model after slicing it along the extending direction of the V-line, the plurality of second contour lines corresponding one-to-one with the plurality of first contour lines, and the plurality of second contour lines each corresponding to a plurality of slices of the complex model. Before printing the complex model based on the print trajectory, the method further includes printing the internal grid corresponding to each slice, using the second contour line corresponding to each slice as the print trajectory of the internal grid corresponding to each slice, Obtaining the layer switching point for each of the aforementioned slices is: This includes setting the intersection of the second contour line of the internal grid corresponding to each slice and the V line as the layer switching point of the internal grid corresponding to each slice. A three-dimensional fused deposition modeling method for complex models as described in claim 3.

5. After dividing the aforementioned complex model into multiple slices, For each slice, a cutting circle is created centered on the layer switching point in the first contour line, the cutting circle intersects the second contour line at least partially, the first and second contour lines within the cutting circle are removed, and the print start and end points of the first contour line and the print start and end points of the second contour line are formed. The print endpoint of the first contour of the nth layer, the print start point of the second contour of the nth layer, the print endpoint of the second contour of the nth layer, and the print start point of the first contour of the (n+1)th layer are joined together at the layer switching point of the first contour of the (n+1)th layer, wherein the layer switching point of the first contour of the (n+1)th layer is the layer switching point between the print trajectory of the nth layer of the complex model and the print trajectory of the (n+1)th layer, and this is continued until the print trajectories of all slices of the complex model are obtained, and all slices of the complex model are printed, provided that n ≥ 1, and the print trajectory of each slice includes the print trajectory of the outer contour corresponding to each slice and the print trajectory of the inner grid corresponding to each slice, further comprising: A three-dimensional fused deposition modeling method for complex models as described in claim 4.

6. The aforementioned complex model includes multiple model segments, and printing the aforementioned complex model is This includes printing each of the plurality of model segments, joining the printed plurality of model segments together to form the complex model, A three-dimensional fused deposition modeling method for a complex model as described in claim 1.

7. The V-line of each model segment is used as an alignment line when joining two adjacent model segments of the same model segment. A three-dimensional fused deposition modeling method for complex models as described in claim 6.

8. The UV lines are obtained based on the UV map axes of the complex model. A three-dimensional fused deposition modeling method for complex models according to any one of claims 1 to 7.

9. The V-line is located on the unused surface of the complex model. A three-dimensional fused deposition modeling method for complex models according to any one of claims 1 to 7.

10. The unused surface includes the bottom or back of the complex model. A three-dimensional fused deposition modeling method for a complex model as described in claim 9.

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