Automatic parametric modeling method and device for three-dimensional groove model and medium
By employing an automated parametric modeling method and utilizing offset, stretching, and ruled surface generation techniques, the problems of high cost and low accuracy in creating 3D bevel models have been solved, achieving efficient and accurate 3D bevel model construction.
Patent Information
- Application Number
- CN202510830242.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-20
- Publication Date
- 2025-11-11
AI Technical Summary
In existing technologies, the creation of 3D models of bevels relies on manual modeling, which is costly and has low accuracy, failing to balance efficiency and quality.
An automatic parametric modeling method is adopted to construct a three-dimensional model of the bevel by using preset parameters such as reference plane, shell thickness, and bevel position for offset, stretching, intersection and ruled surface generation.
It improves modeling efficiency and quality, ensures the accuracy and precision of the 3D model of the bevel, and saves modeling time and costs.
Smart Images
Figure CN120930312A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of parametric modeling technology, and in particular to an automatic parametric modeling method, device and medium for bevel 3D models. Background Technology
[0002] Parametric modeling is a computer-aided design method that emerged in the late 1980s and gradually gained dominance. PTC proposed the parametric modeling method and pioneered its introduction in Pro / E. SDRC proposed the variable design method and applied it in I-DEAS. Although the two systems have different names and differ in how they handle the underlying constraints, they are essentially both about model parameterization. Parametric modeling involves creating a sketch at the beginning of the design process, then gradually applying geometric and dimensional constraints to the sketch according to the design requirements, and driving model changes based on these constraints. Therefore, parametric design is "constraint-based" design that allows dimensions to drive model changes.
[0003] Bevel modeling has evolved from relying entirely on manual drawing to semi-automatic and fully automated modeling. Semi-automatic bevel modeling involves manually creating bevel models after categorizing and numbering them, then controlling the placement of specific numbered bevels in specific locations, which only saves manpower to a certain extent. Fully automated modeling relies entirely on parameter-driven primitives to build 2D bevel models, greatly saving manpower and facilitating standardized annotation; however, the resulting model is only a 2D schematic and cannot be used for machining simulation.
[0004] There are two main methods for parametric modeling: parametric modeling using basic features and parametric modeling using sketches. Parametric modeling using basic features first requires shape analysis of the model, decomposing it into basic geometric elements such as cuboids, cylinders, cones, and spheres. These basic geometric elements can serve as principal features; other features cannot serve as principal features but can only have dependent or reference relationships with them. Datum features include datum planes, datum axes, and datum coordinate systems. These features serve as positioning datums between principal and auxiliary features, and can be parameter-driven during the modeling process. Features such as extrusion, rotation, sweep, ruled lines, and tubes manipulate basic curves and surfaces and can be combined with sketches for parametric modeling. Parametric modeling using sketches involves creating a two-dimensional graphic that is associated with the solid model. Dimensions can drive changes in the sketch plane, and modifications to the constraints added to the sketch object or their values can change the design parameters, thereby altering the object's characteristics. Parametric solid models are generated by performing operations such as stretching, rotating, and sweeping on the cross-sectional curves created on the sketch. This allows for the extraction of parameters from the cross-sectional curves and stretching parameters to drive the overall model's dimensions. During the modeling process, only one master feature exists, and all other features are attached to the master feature, positioned using the master feature's reference points, and maintain a fixed positional relationship with the master feature.
[0005] The aforementioned techniques have not yet been applied to the creation of 3D models of bevels. While the creation of 2D bevel annotation diagrams primarily utilizes dimension-driven 2D primitives, the feasibility of these techniques in creating 3D bevel models has been discussed. However, the characteristics of 3D bevel models are more complex and require further summarization and analysis.
[0006] Currently, the creation of 3D models of bevels mainly adopts a step-by-step manual modeling method, which has many drawbacks. Firstly, it fails to summarize the characteristics of bevels, resulting in a lack of focus during the modeling process. Secondly, it lacks reasonable constraints, making it impossible to achieve efficient and rapid batch creation of bevel models. More importantly, this method cannot guarantee the accuracy of the bevel model's dimensions and topology. Therefore, existing technologies cannot balance efficiency and quality, leading to persistently high costs. Summary of the Invention
[0007] Therefore, the technical problem to be solved by the present invention is to overcome the problem that the creation of three-dimensional models of bevels in the prior art relies on manual modeling, which is costly and has low accuracy.
[0008] To address the aforementioned technical problems, this invention provides an automatic parametric modeling method for three-dimensional bevel models, comprising: Preset reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter; The reference plane is used as the outer surface of the shell; Using the opening direction as the offset direction and the shell thickness as the offset distance, the reference plane is offset to obtain the inner surface of the shell; Using the opening direction as the offset direction and the outer edge depth of the bevel as the offset distance, the reference plane is offset to obtain the surface where the inner contour of the outer bevel is located. Based on the preset size classification benchmark and the inner diameter of the opening, the inner side of the shell or the inner contour of the outer bevel is selected for offset to obtain the inner contour of the inner bevel. Based on the bevel location and opening direction, obtain a two-dimensional sketch of the bevel; on the two-dimensional sketch of the bevel, obtain the outline of the bottom hole based on the dimensional parameters of the bottom hole shape, and extrude it to obtain the initial bottom hole cylindrical surface; Intersect the initial bottom hole cylindrical surface with the inner contour surface of the inner bevel and the inner contour surface of the outer bevel respectively to obtain the corresponding inner contour model of the inner bevel and the inner contour model of the outer bevel. Enlarge the bottom hole outline by a specific factor and stretch it to obtain the enlarged bottom hole cylindrical surface; intersect the enlarged bottom hole cylindrical surface with the inner side and outer side of the shell respectively to obtain the corresponding inner bevel outer contour model and outer bevel outer contour model. A ruled surface is generated based on the inner contour model of the inner bevel and the inner contour model of the outer bevel, which serves as the connecting surface; a ruled surface is generated based on the inner contour model of the inner bevel and the outer contour model of the inner bevel to obtain the inner bevel; a ruled surface is generated based on the inner contour model of the outer bevel and the outer contour model of the outer bevel to obtain the outer bevel. The connecting surface, inner bevel, and outer bevel are stitched together to obtain a three-dimensional model of the bevel.
[0009] Preferably, based on a preset size classification benchmark and the inner diameter of the opening, the inner surface of the shell or the inner contour of the outer bevel is selected for offset to obtain the inner contour of the inner bevel, including: If the inner diameter of the opening is smaller than the preset size classification benchmark, the opposite direction of the opening direction is used as the offset direction, and the inner depth of the bevel is used as the offset distance to offset the inner side of the shell and obtain the surface where the inner contour of the inner bevel is located. If the inner diameter of the opening is not less than the preset size classification benchmark, then the opening direction is used as the offset direction, and the preset offset distance is used to offset the surface where the inner contour of the outer bevel is located, so as to obtain the surface where the inner contour of the inner bevel is located.
[0010] Preferably, the preset offset distance is a fixed root retention distance.
[0011] Preferably, the dimensional parameters of the bottom hole shape include: When the bottom hole is circular, the dimensional parameter is the diameter of the circle; When the bottom hole is square, the dimensional parameters include the length, width, rounding radius, and orientation of the long side of the square. When the bottom hole is waist-shaped, the dimensional parameters include the length and width of the waist and the orientation of the waist axis.
[0012] Preferably, the inner diameter of the opening includes: When the bottom hole is circular, the inner diameter of the opening is the diameter of the circle; When the bottom hole is square, the inner diameter of the opening is the larger of the length and width of the square. When the bottom hole is waist-shaped, the inner diameter of the opening is the larger of the length and width of the waist.
[0013] Preferably, the specific factor by which the bottom hole profile is enlarged is: times, Indicates the inner diameter of the opening. Indicates the bevel width.
[0014] Preferably, the ruled surface is constructed using a dot-ruled method, including: Discretize the first contour and the second contour into a first ordered set of discrete points and a second ordered set of discrete points of equal number; Take any discrete point in the first ordered discrete point set and the discrete point with the smallest distance in the second ordered discrete point set as a pair of connection points; Connect a pair of connection points with straight line segments to obtain the straight line segments corresponding to each pair of connection points, forming a ruled surface.
[0015] Preferably, the reference surface is initialized and biased using a surface STP model.
[0016] This embodiment provides a modeling device based on the automatic parametric modeling method for bevel 3D models as described above, including: The parameter input module allows input of the reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. The modeling module uses a reference plane as the outer surface of the shell; it offsets the reference plane with the opening direction as the offset direction and the shell thickness as the offset distance to obtain the inner surface of the shell; it offsets the reference plane with the opening direction as the offset direction and the outer depth of the bevel as the offset distance to obtain the surface containing the inner contour of the outer bevel; based on a preset size classification reference and the inner diameter of the opening, it selects either the inner surface of the shell or the surface containing the inner contour of the outer bevel for offset to obtain the surface containing the inner contour of the inner bevel; based on the bevel position and the opening direction, it obtains a 2D sketch of the bevel; on the 2D sketch of the bevel, based on the size parameters of the bottom hole shape, it obtains the bottom hole contour and extrudes it to obtain the initial bottom hole cylindrical surface; it then connects the initial bottom hole cylindrical surface with the inner wheel of the inner bevel. The inner contour of the inner bevel and the outer bevel intersect to obtain the corresponding inner bevel inner contour model and outer bevel inner contour model; the bottom hole contour is enlarged by a specific factor and stretched to obtain the enlarged bottom hole cylindrical surface; the enlarged bottom hole cylindrical surface intersects with the inner side and outer side of the shell to obtain the corresponding inner bevel outer contour model and outer bevel outer contour model; a ruled surface is generated based on the inner bevel inner contour model and the outer bevel inner contour model as a connecting surface; a ruled surface is generated based on the inner bevel inner contour model and the inner bevel outer contour model to obtain the inner bevel; a ruled surface is generated based on the outer bevel inner contour model and the outer bevel outer contour model to obtain the outer bevel; the connecting surface, the inner bevel, and the outer bevel are stitched together to obtain the bevel 3D model.
[0017] This embodiment provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it implements the steps of the automatic parametric modeling method for bevel 3D models as described above.
[0018] Compared with the prior art, the above-described technical solution of the present invention has the following advantages: The automatic parametric modeling method for three-dimensional bevel models described in this invention presets the shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. It then offsets the reference plane to obtain the corresponding inner surface of the shell, the surface containing the inner contour of the outer bevel, and the surface containing the inner contour of the inner bevel. Based on a traditional two-dimensional bevel sketch, it constructs the bottom hole contour, performs extrusion and enlargement extrusion to obtain the initial bottom hole cylindrical surface and the enlarged bottom hole cylindrical surface. These intersect with the contour surface to obtain the corresponding inner bevel inner contour model, outer bevel inner contour model, inner bevel outer contour model, and outer bevel outer contour model. Finally, it uses ruled surface generation to construct the connecting surface, inner bevel, and outer bevel. The connecting surface, inner bevel, and outer bevel are then stitched together to obtain the three-dimensional bevel model. This invention is based on bevel features, analyzes the basic and benchmark features of bevels, and sets reasonable size parameters. Users only need to input preset parameters and perform operations such as offsetting, stretching, intersection, stringing, and stitching to obtain the corresponding 3D model of the bevel, saving modeling time and improving modeling efficiency and quality.
[0019] This invention discretizes two contours into two sets of discrete points of the same number, and sorts the discrete points in the set of discrete points to form a straight-lined surface. This solves the problem of inconsistent number of broken edges, inconsistent edge directions, and uneven edge lengths in the contours obtained after intersection, which causes the straight-lined surface to bend and twist. This improves the modeling accuracy of the connecting surface, inner bevel and outer bevel, and thus improves the accuracy of the three-dimensional model of the bevel. Attached Figure Description
[0020] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 This is a flowchart of the automatic parametric modeling method for bevel 3D models of the present invention; Figure 2 These are schematic diagrams of the bevel models corresponding to three different bottom hole shapes; Figure 3 This is a schematic diagram of a bevel modeling for a hole with an inner diameter smaller than a preset size classification benchmark. Figure 4 This is a schematic diagram of a bevel modeling for a hole with an inner diameter not less than a preset size classification benchmark. Figure 5 This is a flowchart of bevel modeling; Figure 6 This is a schematic diagram of the parametric modeling window; Figure 7(a) is a schematic diagram of the input parameters for bevel modeling of a circular bottom hole with an inner diameter of less than 110 mm, and Figure 7(b) is a diagram of the bevel modeling result of a circular bottom hole with an inner diameter of less than 110 mm. Figure 8(a) is a schematic diagram of the input parameters for bevel modeling of a waist-shaped bottom hole with an inner diameter greater than 110 mm, and Figure 8(b) is a diagram of the bevel modeling result of a waist-shaped bottom hole with an inner diameter greater than 110 mm. Figure 9(a) is a schematic diagram of the input parameters for bevel modeling of a square bottom hole with an inner diameter of less than 110 mm, and Figure 9(b) is a diagram of the bevel modeling result of a square bottom hole with an inner diameter of less than 110 mm. Detailed Implementation
[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.
[0022] S101: Preset reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape and opening inner diameter; S102: Use the reference plane as the outer surface of the shell; S103: Using the opening direction as the offset direction and the shell thickness as the offset distance, offset the reference plane to obtain the inner surface of the shell; S104: Using the opening direction as the offset direction and the outer edge depth of the bevel as the offset distance, offset the reference plane to obtain the surface where the inner contour of the outer bevel is located. S105: Based on the preset size classification benchmark and the inner diameter of the opening, select the inner side of the shell or the inner contour of the outer bevel for offset to obtain the inner contour of the inner bevel. S106: Based on the bevel position and opening direction, obtain a two-dimensional sketch of the bevel; on the two-dimensional sketch of the bevel, based on the size parameters of the bottom hole shape, obtain the bottom hole outline, and extrude it to obtain the initial bottom hole cylindrical surface; S107: Intersect the initial bottom hole cylindrical surface with the inner contour surface of the inner bevel and the inner contour surface of the outer bevel respectively to obtain the corresponding inner contour model of the inner bevel and the inner contour model of the outer bevel. S108: Enlarge the bottom hole profile by a specific factor and stretch it to obtain the enlarged bottom hole cylindrical surface; intersect the enlarged bottom hole cylindrical surface with the inner side and outer side of the shell respectively to obtain the corresponding inner bevel outer profile model and outer bevel outer profile model. Specific multiples are times, Indicates the inner diameter of the opening. Indicates the bevel width; S109: Generate a ruled surface based on the inner contour model of the inner bevel and the inner contour model of the outer bevel, as a connecting surface; generate a ruled surface based on the inner contour model of the inner bevel and the outer contour model of the inner bevel to obtain the inner bevel; generate a ruled surface based on the inner contour model of the outer bevel and the outer contour model of the outer bevel to obtain the outer bevel. S110: Sew the connecting surface, inner bevel, and outer bevel together to obtain a three-dimensional model of the bevel.
[0023] Specifically, in step S105, when constructing the surface containing the inner contour of the inner bevel, the following is included: S105-1: If the inner diameter of the opening is smaller than the preset size classification benchmark, the opposite direction of the opening direction is used as the offset direction, and the inner depth of the bevel is used as the offset distance to offset the inner side of the shell to obtain the surface where the inner contour of the inner bevel is located. S105-2: If the inner diameter of the opening is not less than the preset size classification benchmark, then the opening direction is used as the offset direction, and the preset offset distance is used to offset the surface where the inner contour of the outer bevel is located, so as to obtain the surface where the inner contour of the inner bevel is located.
[0024] The preset offset distance is a fixed root retention distance. The fixed root retention distance is a default fixed parameter in the modeling software; the root retention refers to the un-beveled original material part retained at the root of the bevel (i.e., the innermost part of the bevel where it meets the base material). Retaining a certain thickness of root retention during welding can prevent the molten pool from burning through, and at the same time reduce the thermal deformation of the base material caused by excessive beveling, thus ensuring processing accuracy.
[0025] Specifically, refer to Figure 2 The diagram shows a bevel model corresponding to three different bottom hole shapes. The bottom hole shapes in this embodiment include circular, square, and oblong shapes. The dimensional parameters for different bottom hole shapes are as follows: when the bottom hole is circular, the dimensional parameter is the diameter of the circle; when the bottom hole is square, the dimensional parameters include the length, width, rounding radius, and orientation of the long side; when the bottom hole is oblong, the dimensional parameters include the length, width, and orientation of the oblong axis. The inner diameter of the opening for different bottom hole shapes is as follows: when the bottom hole is circular, the inner diameter is the diameter of the circle; when the bottom hole is square, the inner diameter is the larger of the length and width of the square; when the bottom hole is oblong, the inner diameter is the larger of the length and width of the oblong shape.
[0026] The automatic parametric modeling method for 3D bevel models described in this invention inputs shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. It then offsets a reference plane to obtain the corresponding inner shell surface, the surface containing the inner contour of the outer bevel, and the surface containing the inner contour of the inner bevel. Based on a traditional 2D bevel sketch, it constructs the bottom hole contour, performs extrusion and enlarged extrusion to obtain the initial bottom hole cylindrical surface and the enlarged bottom hole cylindrical surface. These intersect with the contour surface to obtain the corresponding inner bevel inner contour model, outer bevel inner contour model, inner bevel outer contour model, and outer bevel outer contour model. Using ruled surface generation, it constructs the connecting surface, inner bevel, and outer bevel. Finally, it stitches the connecting surface, inner bevel, and outer bevel together to obtain the 3D bevel model. This invention is based on bevel features, analyzes the basic and benchmark features of bevels, and sets reasonable size parameters. Users only need to input preset parameters and perform operations such as offsetting, stretching, intersection, stringing, and stitching to obtain the corresponding 3D model of the bevel, saving modeling time and improving modeling efficiency and quality.
[0027] Specifically, in this embodiment of the invention, the ruled surface is constructed using a dot-ruled method, including: Discretize the first contour and the second contour into a first ordered set of discrete points and a second ordered set of discrete points of equal number; Take any discrete point in the first ordered discrete point set and the discrete point with the smallest distance in the second ordered discrete point set as a pair of connection points; Connect a pair of connection points with straight line segments to obtain the straight line segments corresponding to each pair of connection points, forming a ruled surface.
[0028] In this embodiment, the inner contour model of the inner bevel is used as the first contour, and the inner contour model of the outer bevel is used as the second contour. A ruled surface is constructed using a dot-rubbing method as the connecting surface. In this embodiment, the inner contour model of the inner bevel is used as the first contour, and the outer contour model of the inner bevel is used as the second contour. A ruled surface is constructed using a dot-rubbing method as the inner bevel. In this embodiment, the inner contour model of the outer bevel is used as the first contour, and the outer contour model of the outer bevel is used as the second contour. A ruled surface is constructed using a dot-rubbing method as the outer bevel.
[0029] This invention discretizes two contours into two sets of discrete points of the same number, and sorts the discrete points in the set of discrete points to form a straight-lined surface. This solves the problem of inconsistent number of broken edges, inconsistent edge directions, and uneven edge lengths in the contours obtained after intersection, which causes the straight-lined surface to bend and twist. This improves the modeling accuracy of the connecting surface, inner bevel and outer bevel, and thus improves the accuracy of the three-dimensional model of the bevel.
[0030] Based on the above embodiments, in this embodiment of the invention, modeling is performed using the automatic parametric modeling method for three-dimensional bevel models provided by the present invention, including: S201: This invention analyzes and summarizes the characteristics of the bevel, clarifies the user input parameters, and designs a parameter interaction window; According to the shape of the bottom hole, the bevel types in this invention can be divided into three types: circular, oblong, and square.
[0031] To determine the bevel size constraints, the parameters that the user needs to determine include: the bevel face, shell thickness, bevel location, opening direction, depth and width of the inner and outer sides of the bevel, bottom hole shape, and the corresponding size parameters for each of the three shapes. The dimensional parameters corresponding to different shaped bottom holes include: When the bottom hole is circular, the dimension parameter is the diameter; When the bottom hole is square, the dimensional parameters include length, width, rounding radius, and orientation of the long side (the long side is horizontal or vertical relative to the reference axis). When the bottom hole is oblong, the dimensional parameters include the length, width and orientation of the oblong axis (the line connecting the centers of the two circles is horizontal or vertical relative to the reference axis).
[0032] S202: The software constructs the outline; The inner and outer contours of the inner and outer bevels are obtained by offsetting the surface where the bevel is located according to the shell thickness and the inner and outer depths. The bottom hole profile is determined by the shape of the bevel bottom hole; the bottom hole profile is stretched to obtain the intersection of the cylindrical surface with the inner profile of the inner and outer bevels, thus obtaining the inner profile of the inner and outer bevels. The bottom hole profile is expanded by the bevel width, and a cylindrical surface is obtained by stretching. The cylindrical surface intersects with the outer profiles of the inner and outer bevels to obtain the outer profiles of the inner and outer bevels. S203: The software performs contour ruling, obtains the corresponding surfaces, and stitches them together to obtain the 3D model of the bevel. The inner bevel is obtained by running straight lines along its inner and outer contours; the outer bevel is obtained by running straight lines along its inner and outer contours; the inner and outer bevels are then joined together to form the connecting surface between the two bevels; the inner and outer bevels and the connecting surface between the two bevels are then sewn together to form the model. S204: Users design parameters based on bevel characteristics, including: S204-1: Reference surface parameters, including: The curved surface STP model uses this curved surface as the outer surface, that is, the surface where the outer contour of the outer bevel is located; Shell thickness, which is the distance between the inner and outer sides of the shell, is used to determine the surface where the inner bevel's inner contour is located; S204-2: Bottom hole parameters, including: When the bottom hole is square, it includes the length, width, corner radius and the orientation of the long side (horizontal / vertical). When the bottom hole is circular, the diameter is included; When the bottom hole is waist-shaped, it includes: length, width, and axis orientation (horizontal / vertical); where the width is the difference between the diameters of the two circles, and the axis is the line connecting the centers of the two circles; S204-3: Azimuth parameters, including: The position coordinates (x, y, z) represent the center position of the bevel; The opening direction (i,j,k) points from the outside of the shell to the inside of the shell. S204-4: Beveling parameters, including: The inner depth is the distance from the inner surface of the shell to the inner contour of the inner bevel; where the inner diameter of the bevel is not less than the preset size classification benchmark, the distance between the inner contour of the inner bevel and the inner contour of the outer bevel is 2mm. Outer depth: the distance from the outer surface of the shell to the inner contour of the outer bevel; Bevel width, the extension dimension of the outer contour bottom hole relative to the inner contour bottom hole; S205: Model creation using software, including: The bevel creation is divided into two categories based on the size of the opening's inner diameter: one category has an inner diameter greater than or equal to the preset size classification benchmark δmm, and the other category has an inner diameter less than the preset size classification benchmark δmm. For circular bevels, the diameter parameter is taken as the feature dimension; for square and oblong bevels, the maximum length and width parameters are taken as the feature dimensions.
[0033] Reference Figure 3 The image shown is a schematic diagram of a bevel modeling for an opening with an inner diameter smaller than a preset size classification benchmark; refer to... Figure 4 The figure shows a schematic diagram of bevel modeling for a hole with an inner diameter not less than a preset size classification benchmark. Reference Figure 5 The diagram shown is a flowchart of the bevel modeling process, and the specific steps include: S205-1: Read the step model and determine the reference plane, which is the outer side of the shell and also the plane where the outer contour of the outer bevel is located; S205-2: Offset the reference plane along the opening direction by a distance equal to the shell thickness to obtain the inner surface of the shell; S205-3: Offset the reference plane along the opening direction by an offset distance equal to the outer depth of the bevel, to obtain the surface containing the inner contour of the outer bevel; S205-4: Classification criteria for comparing the inner diameter of the opening with the preset size: If the inner diameter of the opening is smaller than the preset size classification benchmark, the inner side of the shell is offset along the opposite direction of the opening, and the offset distance is the inner depth of the bevel, so as to obtain the surface where the inner contour of the inner bevel is located. If the inner diameter of the opening is not less than the preset size classification benchmark, then the inner contour of the inner bevel is obtained by offsetting the outer bevel inner contour surface by 2mm along the opening direction. S205-5: Determine the sketch plane based on the bevel position and the opening direction, and determine the bottom hole outline based on the bottom hole shape and size parameters on this plane; S205-6: The bottom hole profile is stretched into a cylindrical surface, which intersects with the inner profile of the inner bevel to obtain the inner profile of the inner bevel, and intersects with the inner profile of the outer bevel to obtain the inner profile of the outer break. S205-7: Enlarge the outline of the bottom hole Stretch the profile to obtain a cylindrical surface, intersect it with the inner surface of the shell to obtain the inner bevel outer profile, and intersect it with the outer surface of the shell to obtain the outer bevel outer profile. Indicates the inner diameter of the opening. Indicates the bevel width; S205-8: Discretize the inner contour of the inner bevel and the inner contour of the outer bevel into two sets of points with the same number and the minimum distance between the two sets of points. Then, make the two sets of points into a straight line to obtain the bevel connection surface. Similarly, discretize and sort the inner contour of the inner bevel and its outer contour into a straight line to obtain the inner bevel. Discretize and sort the inner contour of the outer bevel and its outer contour into a straight line to obtain the outer bevel. S205-9: Sew the inner bevel, connecting surface, and outer bevel together to form a model.
[0034] In this embodiment, the two contours are discretized into two groups of equal numbers and arranged in order of the minimum relative distance to form straight lines. This solves the problem of the straight lines being deflected and distorted due to the inconsistent number of broken edges, inconsistent edge directions, and uneven edge lengths of the contours obtained after intersection.
[0035] Based on the above description, this embodiment summarizes the characteristics of bevels, analyzes their basic and datum features, designs reasonable dimensional parameters, and summarizes general modeling steps. The complex modeling process is completed by code, allowing users to obtain an accurate model simply by inputting the corresponding parameters, saving time and improving modeling efficiency and quality. Simultaneously, a suitable parameter input window is designed, enabling automatic generation of bevel models simply by inputting parameters or parameter files. Reference Figure 6 The image shown is a schematic diagram of the parametric modeling window; clicking "Parametric Modeling" will bring up a pop-up window as follows. Figure 6 In the dialog box shown, select the curved surface model as the reference plane, input the shell thickness, select the bottom hole shape, input the bottom hole size parameters according to the bottom hole shape, and then input parameters such as the inner and outer depth of the bevel, the bevel width, the bevel direction, and the bevel position. Click OK to create the model and attach it to the model tree.
[0036] Specifically, this paper categorizes bevels into waist-shaped, rectangular, and circular types based on their basic characteristics. The location and opening direction of the bevel are used to determine the reference plane of the sketch, and dimensional parameters are summarized to define the two-dimensional shape. A three-dimensional bevel model is then established using features such as offset, stretching, intersection, ruling, and stitching. In this embodiment, for a certain type of part, 110mm is used as the preset dimensional classification benchmark, dividing bevels into two categories: those greater than or equal to 110mm and those less than 110mm, and establishing corresponding bevel models.
[0037] Referring to Figure 7, Figure 7(a) is a schematic diagram of the input parameters for beveling a circular bottom hole with an inner diameter less than 110mm, and Figure 7(b) is a modeling result of beveling a circular bottom hole with an inner diameter less than 110mm; referring to Figure 8, Figure 8(a) is a schematic diagram of the input parameters for beveling a waist-shaped bottom hole with an inner diameter greater than 110mm, and Figure 8(b) is a modeling result of beveling a waist-shaped bottom hole with an inner diameter greater than 110mm; referring to Figure 9, Figure 9(a) is a schematic diagram of the input parameters for beveling a square bottom hole with an inner diameter less than 110mm, and Figure 9(b) is a modeling result of beveling a square bottom hole with an inner diameter less than 110mm.
[0038] Based on the above embodiments, the present invention provides an automatic parametric modeling device for three-dimensional bevel models, the specific device including: The parameter input module allows input of the reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. The modeling module uses a reference plane as the outer surface of the shell; it offsets the reference plane with the opening direction as the offset direction and the shell thickness as the offset distance to obtain the inner surface of the shell; it offsets the reference plane with the opening direction as the offset direction and the outer depth of the bevel as the offset distance to obtain the surface containing the inner contour of the outer bevel; based on a preset size classification reference and the inner diameter of the opening, it selects either the inner surface of the shell or the surface containing the inner contour of the outer bevel for offset to obtain the surface containing the inner contour of the inner bevel; based on the bevel position and the opening direction, it obtains a 2D sketch of the bevel; on the 2D sketch of the bevel, based on the size parameters of the bottom hole shape, it obtains the bottom hole contour and extrudes it to obtain the initial bottom hole cylindrical surface; it then connects the initial bottom hole cylindrical surface with the inner wheel of the inner bevel. The inner contour of the inner bevel and the outer bevel intersect to obtain the corresponding inner bevel inner contour model and outer bevel inner contour model; the bottom hole contour is enlarged by a specific factor and stretched to obtain the enlarged bottom hole cylindrical surface; the enlarged bottom hole cylindrical surface intersects with the inner side and outer side of the shell to obtain the corresponding inner bevel outer contour model and outer bevel outer contour model; a ruled surface is generated based on the inner bevel inner contour model and the outer bevel inner contour model as a connecting surface; a ruled surface is generated based on the inner bevel inner contour model and the inner bevel outer contour model to obtain the inner bevel; a ruled surface is generated based on the outer bevel inner contour model and the outer bevel outer contour model to obtain the outer bevel; the connecting surface, the inner bevel, and the outer bevel are stitched together to obtain the bevel 3D model.
[0039] The automatic parametric modeling device for bevel 3D models in this embodiment is used to implement the aforementioned automatic parametric modeling method for bevel 3D models. Therefore, the specific implementation of the automatic parametric modeling device for bevel 3D models can be found in the embodiment section of the automatic parametric modeling method for bevel 3D models mentioned above. For example, the parameter input module is used to implement step S101 in the above-mentioned automatic parametric modeling method for bevel 3D models; the modeling module is used to implement steps S102 to S109 in the above-mentioned automatic parametric modeling method for bevel 3D models. Therefore, its specific implementation can be referred to the description of the corresponding embodiments, and will not be repeated here.
[0040] Based on the above embodiments, this invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the automatic parametric modeling method for bevel 3D models as described above.
[0041] The automatic parametric modeling method for three-dimensional bevel models described in this invention presets the shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. It then offsets the reference plane to obtain the corresponding inner surface of the shell, the surface containing the inner contour of the outer bevel, and the surface containing the inner contour of the inner bevel. Based on a traditional two-dimensional bevel sketch, it constructs the bottom hole contour, performs extrusion and enlargement extrusion to obtain the initial bottom hole cylindrical surface and the enlarged bottom hole cylindrical surface. These intersect with the contour surface to obtain the corresponding inner bevel inner contour model, outer bevel inner contour model, inner bevel outer contour model, and outer bevel outer contour model. Finally, it uses ruled surface generation to construct the connecting surface, inner bevel, and outer bevel. The connecting surface, inner bevel, and outer bevel are then stitched together to obtain the three-dimensional bevel model. This invention is based on bevel features, analyzes the basic and benchmark features of bevels, and sets reasonable size parameters. Users only need to input preset parameters and perform operations such as offsetting, stretching, intersection, stringing, and stitching to obtain the corresponding 3D model of the bevel, saving modeling time and improving modeling efficiency and quality.
[0042] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0043] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0044] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0045] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0046] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. An automatic parametric modeling method for three-dimensional models of bevels, characterized in that, include: Preset reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape and opening inner diameter; The reference plane is used as the outer surface of the shell; Using the opening direction as the offset direction and the shell thickness as the offset distance, the reference plane is offset to obtain the inner surface of the shell; Using the opening direction as the offset direction and the outer edge depth of the bevel as the offset distance, the reference plane is offset to obtain the surface where the inner contour of the outer bevel is located. Based on the preset size classification benchmark and the inner diameter of the opening, the inner side of the shell or the inner contour of the outer bevel is selected for offset to obtain the inner contour of the inner bevel. Based on the bevel location and opening direction, obtain a two-dimensional sketch of the bevel; on the two-dimensional sketch of the bevel, obtain the outline of the bottom hole based on the dimensional parameters of the bottom hole shape, and extrude it to obtain the initial bottom hole cylindrical surface; Intersect the initial bottom hole cylindrical surface with the inner contour surface of the inner bevel and the inner contour surface of the outer bevel respectively to obtain the corresponding inner contour model of the inner bevel and the inner contour model of the outer bevel. Enlarge the bottom hole outline by a specific factor and stretch it to obtain the enlarged bottom hole cylindrical surface; intersect the enlarged bottom hole cylindrical surface with the inner side and outer side of the shell respectively to obtain the corresponding inner bevel outer contour model and outer bevel outer contour model. A ruled surface is generated based on the inner contour model of the inner bevel and the inner contour model of the outer bevel, which serves as the connecting surface; a ruled surface is generated based on the inner contour model of the inner bevel and the outer contour model of the inner bevel to obtain the inner bevel; a ruled surface is generated based on the inner contour model of the outer bevel and the outer contour model of the outer bevel to obtain the outer bevel. The connecting surface, inner bevel, and outer bevel are stitched together to obtain a three-dimensional model of the bevel.
2. The automatic parametric modeling method for three-dimensional bevel models according to claim 1, characterized in that, Based on a preset size classification benchmark and the inner diameter of the opening, the inner surface of the shell or the inner contour of the outer bevel is selected for offset to obtain the inner contour of the inner bevel, including: If the inner diameter of the opening is smaller than the preset size classification benchmark, the opposite direction of the opening direction is used as the offset direction, and the inner depth of the bevel is used as the offset distance to offset the inner side of the shell and obtain the surface where the inner contour of the inner bevel is located. If the inner diameter of the opening is not less than the preset size classification benchmark, then the opening direction is used as the offset direction, and the preset offset distance is used to offset the surface where the inner contour of the outer bevel is located, so as to obtain the surface where the inner contour of the inner bevel is located.
3. The automatic parametric modeling method for three-dimensional bevel models according to claim 2, characterized in that, The preset offset distance is a fixed root retention distance.
4. The automatic parametric modeling method for three-dimensional bevel models according to claim 1, characterized in that, The dimensional parameters of the bottom hole shape include: When the bottom hole is circular, the dimensional parameter is the diameter of the circle; When the bottom hole is square, the dimensional parameters include the length, width, rounding radius, and orientation of the long side of the square. When the bottom hole is waist-shaped, the dimensional parameters include the length and width of the waist and the orientation of the waist axis.
5. The automatic parametric modeling method for three-dimensional bevel models according to claim 4, characterized in that, The inner diameter of the opening includes: When the bottom hole is circular, the inner diameter of the opening is the diameter of the circle; When the bottom hole is square, the inner diameter of the opening is the larger of the length and width of the square. When the bottom hole is waist-shaped, the inner diameter of the opening is the larger of the length and width of the waist.
6. The automatic parametric modeling method for three-dimensional bevel models according to claim 1, characterized in that, The specific factor by which the bottom hole profile is enlarged is times, Indicates the inner diameter of the opening. Indicates the bevel width.
7. The automatic parametric modeling method for three-dimensional bevel models according to claim 1, characterized in that, Constructing ruled surfaces using the point-ruling method includes: Discretize the first contour and the second contour into a first ordered set of discrete points and a second ordered set of discrete points of equal number; Take any discrete point in the first ordered discrete point set and the discrete point with the smallest distance in the second ordered discrete point set as a pair of connection points; Connect a pair of connection points with straight line segments to obtain the straight line segments corresponding to each pair of connection points, forming a ruled surface.
8. The automatic parametric modeling method for three-dimensional bevel models according to claim 1, characterized in that, The reference surface is initialized and biased using the surface STP model.
9. A modeling apparatus based on the automatic parametric modeling method for three-dimensional bevel models as described in any one of claims 1 to 8, characterized in that, include: The parameter input module allows input of the reference plane, shell thickness, bevel position, bevel direction, bevel width, outer bevel depth, inner bevel depth, bottom hole shape, and opening inner diameter. The modeling module uses a reference plane as the outer surface of the shell; it uses the opening direction as the offset direction and the shell thickness as the offset distance to offset the reference plane and obtain the inner surface of the shell. Using the opening direction as the offset direction and the outer edge depth of the bevel as the offset distance, the reference plane is offset to obtain the surface where the inner contour of the outer bevel is located. Based on a preset size classification benchmark and the inner diameter of the opening, the inner surface of the shell or the inner contour of the outer bevel is selected and offset to obtain the inner contour of the inner bevel. A two-dimensional sketch of the bevel is obtained based on the bevel position and the opening direction. On the two-dimensional sketch of the bevel, the bottom hole contour is obtained based on the dimensional parameters of the bottom hole shape and is extruded to obtain the initial bottom hole cylindrical surface. The initial bottom hole cylindrical surface is intersected with the inner contour of the inner bevel and the inner contour of the outer bevel, respectively, to obtain the corresponding inner bevel inner contour model and outer bevel inner contour model. The bottom hole contour is then enlarged by a specific factor. Count and stretch to obtain the enlarged bottom hole cylindrical surface; intersect the enlarged bottom hole cylindrical surface with the inner side and outer side of the shell respectively to obtain the corresponding inner bevel outer contour model and outer bevel outer contour model; generate ruled surfaces based on the inner bevel inner contour model and outer bevel inner contour model as the connecting surface; generate ruled surfaces based on the inner bevel inner contour model and inner bevel outer contour model to obtain the inner bevel; generate ruled surfaces based on the outer bevel inner contour model and outer bevel outer contour model to obtain the outer bevel; stitch the connecting surface, inner bevel and outer bevel together to obtain the bevel 3D model.
10. 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 steps of the automatic parametric modeling method for bevel 3D models as described in any one of claims 1 to 8.