Fusion cutting method and device for denture prosthesis and storage medium

Abstract

The invention relates to the technical field of dental medicine, in particular to a fusion cutting method, device and equipment for a denture prosthesis and a storage medium. The method comprises the following steps: acquiring at least two prosthesis models; the prosthesis model is preprocessed, and an initial outer layer model of the prosthesis is reserved; determining a penetrating area and a non-penetrating area between the initial outer layer models, and preprocessing the penetrating area to obtain a cutting surface set between the initial outer layer models; combining the cutting surface set and the non-penetrating area to obtain a cut target outer layer; and performing fairing treatment on the target outer layer, and combining the target outer layer subjected to the fairing treatment with the inner layer model to obtain a cut prosthesis model. Compared with the prior art, the method has the advantages that the surface which is as flat as possible is constructed in the penetrating area space of the two models to serve as the reference surface, so that the vertexes of the penetrating areas of the two models are displaced to the reference surface, and accurate cutting of the false tooth model is realized.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of dental medicine, and in particular to a fusion cutting method, device and storage medium for a denture restoration. Background Art

[0002] In modern dental restorations, when users design dentures, they need to carefully select tooth templates based on the appearance of the patient's natural teeth. For front teeth, users often pay special attention to the aesthetic characteristics of the teeth, among which the degree of wear is one of the important concerns of users. However, natural teeth have a variety of shapes, and the number of pre-set standard tooth models is limited. Therefore, when users choose tooth templates, it is sometimes difficult to choose a tooth template whose aesthetic characteristics match the patient's natural teeth very well.

[0003] Currently, in the design process of denture restorations, the method for dealing with penetration between models is generally to use a cutting algorithm to calculate the Boolean difference between the target model and the source model, retain the complete target model, and cut off the penetrating part of the source model. This method is suitable for dealing with the model penetration problem between the denture restoration and the scanned part, but if the penetrating models are all restorations, this method is difficult to achieve good results and is easy to destroy the shape of the denture model.

[0004] Therefore, it is necessary to propose a fusion cutting method for denture restorations to improve the technical problem of poor fusion cutting effect of adjacent denture restorations in the prior art. Summary of the invention

[0005] One purpose of the embodiments of the present application is to provide a fusion cutting method, device and storage medium for a denture restoration, so as to solve the technical problems in the related art that the process of denture feature editing is cumbersome, difficult to operate and has high requirements on users.

[0006] In a first aspect, an embodiment of the present application provides a fusion cutting method for a denture restoration, the method comprising:

[0007] Acquire at least two restoration models, wherein the restoration models include an inner layer model and an initial outer layer model;

[0008] Preprocessing the restoration model to separate the inner layer model of the restoration model, retaining the initial outer layer model of the restoration, and the initial outer layer models of different restoration models are in contact with each other to form a penetration area and a non-penetration area;

[0009] Determining a penetration region and a non-penetration region between the initial outer layer models, and preprocessing the penetration region to obtain a set of cutting surfaces between the initial outer layer models;

[0010] Merging the cutting surface set and the non-penetration area to obtain a target outer layer after cutting;

[0011] According to a preset grid smoothing algorithm, the target outer layer is smoothed, and the smoothed target outer layer is combined with the inner layer model of the restoration model to obtain the restoration model after cutting.

[0012] In combination with the first aspect, in a possible implementation manner, determining a reference surface set between the restoration models based on the initial outer layer model of the restoration, wherein the reference surface belongs to the inside of the penetration region between the restoration models, includes:

[0013] Performing a sealing process on the initial outer layer model;

[0014] After the sealing process, the penetration area of ​​the initial outer layer model is separated to obtain two sub-models of the initial outer layer model respectively;

[0015] The model with the smaller area among the two sub-models is the target model;

[0016] The reference surface is determined according to the target model.

[0017] In combination with the first aspect, in a possible implementation manner, the closing process of the initial outer layer model includes:

[0018] Calculate the geometric center coordinates P of the neck edge line in the initial outer layer model and the maximum length L of the grid bounding box;

[0019] Fitting a least square surface with the coordinates of the vertices of the neck margin line, calculating the normal vector of the least square surface, and taking the direction N facing away from the grid in the positive and negative directions of the normal vector;

[0020] Insert a new vertex V at the position where point P moves L length along direction N, and its coordinates are P+N*L;

[0021] The vertex V is respectively combined with every two adjacent vertices of the neck edge line to form a facet, so as to obtain a closed mesh of the initial outer layer model.

[0022] In combination with the first aspect, in a possible implementation manner, determining the reference surface according to the target model includes:

[0023] Determine the minimum area grid of the target model by using a grid smoothing algorithm;

[0024] The grid is re-gridged to obtain a grid with uniform surface patches as the reference surface.

[0025] In combination with the first aspect, in a possible implementation, after the sealing process, the penetration area of ​​the initial outer layer model is separated to obtain two sub-models, including:

[0026] Determine a collision line between two initial outer-layer models, wherein the collision line is a set of line segments on a plurality of triangular facets;

[0027] The endpoints of the line segments on the collision line and the vertices on the triangular facet where the line segments are located and located inside another model form a new facet, and the facet is the edge of the penetration area;

[0028] The new facet and the facets whose three vertices are inside another model are combined into a new mesh model. If there are disconnected areas, multiple mesh models are generated.

[0029] In combination with the first aspect, in a possible implementation manner, determining the cutting surface set based on the reference surface includes:

[0030] Splitting the initial outer layer model, and respectively determining penetration area grid sets of two initial outer layer models;

[0031] Match the mesh sets of the penetration areas of the two initial outer models with the mesh sets of the reference surface, and determine the mesh with the smallest distance sum as the matching mesh by calculating the distance sum between the nearest boundary points of the two meshes. The matching mesh includes the penetration areas SubMeshA and SubMeshB of the two initial outer models, and the corresponding reference surface RefMesh;

[0032] The cutting surface set is determined according to the matching grid.

[0033] In combination with the first aspect, in a possible implementation manner, determining the cutting surface set according to the matching grid includes:

[0034] Perform mesh smoothing on SubMesh (SubMeshB, and / or SubMeshB) to obtain the minimum area mesh;

[0035] Re-meshing the vertices other than the boundary vertices in the SubMesh mesh to obtain a uniform mesh of the face;

[0036] Calculate the least squares surface of the SubMesh mesh boundary vertices and take its normal N;

[0037] If the SubMesh contains a neck line, the neck line influence area Rn is calculated. Rn includes the vertices in the three neighborhoods of the neck line excluding the neck line vertex, and the vertices within the radius r of the neck line vertex. The value of r is linearly related to the minimum distance d from the neck line vertex to RefMesh.

[0038] Calculate the projection coordinates of each vertex of the above mesh except the Rn region on the reference surface RefMesh in the direction N. If the projection coordinates can be calculated correctly, move the vertex to this projection coordinates;

[0039] The Rn region is smoothed with a local minimum curvature change by using a grid smoothing algorithm to obtain the cutting surface set.

[0040] In combination with the first aspect, in a possible implementation manner, the smoothing of the target outer layer according to a preset grid smoothing algorithm includes:

[0041] Determine the set of areas to be smoothed ToFairList, wherein ToFairList includes the edge vertices of the sub-models of the initial outer layer model that are in contact with each other, and the vertices whose projection coordinates on the reference surface RefMesh cannot be calculated when N is the direction outside the Rn region in the SubMesh mesh when determining the cutting surface set, wherein Rn is the neck margin line influence region, and N is the normal direction of the least squares surface of the SubMesh mesh boundary vertex;

[0042] The set of regions to be smoothed ToFairList is smoothed with a local minimum curvature change.

[0043] In a second aspect, an embodiment of the present application further proposes an electronic device, comprising a memory and a processor, wherein the memory is connected to the processor, and the processor is used to execute one or more computer programs stored in the memory. When the processor executes the one or more computer programs, the electronic device implements a method as described in any one of the first aspects.

[0044] In a third aspect, an embodiment of the present application further proposes a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the processor executes the method as described in any one of the first aspects.

[0045] The embodiments of the present application can achieve the following technical effects:

[0046] Based on the method proposed in the embodiment of the present application, when cutting and fusing adjacent denture restorations, a part of the area of ​​each of the two models is cut, and a surface that is as flat as possible is constructed as a reference surface within the penetration area space of the two models, thereby reducing the damage to the model morphology. In addition, a cutting scheme is proposed when the model has a cervical margin line penetrating. While ensuring that the cervical margin line remains fixed, the cutting operation can still be performed to shift the vertices of the penetration area of ​​the two models to the reference surface, thereby achieving precise cutting of the denture model. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0048] Figure 1 A schematic diagram of a flow chart of a fusion cutting method for a denture restoration provided in an embodiment of the present application;

[0049] Figure 2 is a schematic diagram of a sub-model obtained from a penetration region after separation provided in an embodiment of the present application;

[0050] Figure 3 is a schematic diagram of a reference surface mesh model provided in an embodiment of the present application;

[0051] Figure 4 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0053] It should be noted that, if there is no conflict, the various features in the embodiments of the present application can be combined with each other, all within the scope of protection of the present application. In addition, although the functional module division is performed in the device schematic diagram and the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in a sequence different from the module division in the device or the flow chart. Furthermore, the words "first", "second", "third", etc. used in this application do not limit the data and execution order, but only distinguish the same items or similar items with basically the same functions and effects.

[0054] In the first place, see Figure 1 The present application provides a method for fusion cutting of a denture restoration, the method comprising:

[0055] Step S10, obtaining at least two restoration models, wherein the restoration model includes an inner layer model and an initial outer layer model;

[0056] Step S20, preprocessing the restoration model to separate the inner layer model of the restoration model, retaining the initial outer layer model of the restoration, and the initial outer layer models of different restoration models are in contact with each other to form a penetration area and a non-penetration area;

[0057] Step S30, determining the penetration area and the non-penetration area between the initial outer layer models, and preprocessing the penetration area to obtain a set of cutting surfaces between the initial outer layer models;

[0058] Step S40, merging the cutting surface set and the non-penetrating area to obtain the target outer layer after cutting

[0059] Step S50, smoothing the target outer layer according to a preset grid smoothing algorithm, and combining the smoothed target outer layer with the inner layer model of the restoration model to obtain a cut restoration model.

[0060] It is easy to understand that the denture restoration model is divided into two layers, inner and outer layers. In order to facilitate subsequent processing, the inner and outer layers need to be separated, and only the outer layer model is processed later. Unless otherwise specified, the denture model in the subsequent content of this embodiment refers to the outer layer model.

[0061] The cutting surface refers to the surface that is in close contact with the model after cutting. The cutting surface needs to be as flat as possible to avoid undercuts that affect the wearing of the denture. If the vertex is inside the model, it is said to be in the penetration area, otherwise, it is in the non-penetration area.

[0062] It is easy to understand that the vertices of the penetration area of ​​the model are processed and displaced to the reference surface, so that the penetration area can coincide with the reference surface. This can achieve two purposes: one is to make the penetration areas of the two models closely contact at the position of the reference surface, and the other is that the cutting surface replicates the shape of the reference surface and becomes as smooth as possible.

[0063] Specifically, in the above embodiment, determining the reference surface set between the restoration models includes:

[0064] The initial outer layer model is closed; after the closing process, the penetration area of ​​the initial outer layer model is separated to obtain two sub-models of the initial outer layer model respectively; the model with a smaller area in the two sub-models is the target model; and the reference surface is determined according to the target model.

[0065] In order to facilitate subsequent processing, it is necessary to separate the penetration area of ​​the model to obtain two separate models. Figure 2 ,like Figure 2The figure on the left shows the penetration position, the figure in the middle shows the position of the penetration area in the model, and the model on the right is the separated penetration area.

[0066] As a feasible implementation method, the collision area sub-models of the two models can be calculated respectively by the following method:

[0067] First, the collision line of the two models is calculated. The collision line is a set of line segments located on a series of triangular faces. Then, the endpoints of the collision line segments and the vertices on the triangular faces on which they are located located inside the other model are combined into new faces. These faces are the edges of the penetration area. Finally, the above new faces and the faces whose three vertices are inside the other model are combined into a new mesh model. If there are unconnected areas, multiple mesh models are generated.

[0068] Furthermore, the closing processing of the initial outer layer model includes: calculating the geometric center coordinates P of the neck edge line in the initial outer layer model, and the maximum length L of the mesh bounding box; fitting the least squares surface with the coordinates of the vertices of the neck edge line, calculating the normal vector of the least squares surface, and taking the direction N facing away from the mesh in the positive and negative directions of the normal vector; inserting a new vertex V at the position after point P moves L length along the direction N, and its coordinates are P+N*L; forming a facet with the vertex V and every two adjacent vertices of the neck edge line to obtain a closed mesh of the initial outer layer model.

[0069] Furthermore, the step of determining the reference surface includes: using a mesh smoothing algorithm to determine the minimum area mesh of the target model; and re-meshing the mesh to obtain a mesh with uniform surface patches as the reference surface.

[0070] Please refer to Figure 3 , Figure 3 The schematic diagram of the reference surface mesh model is shown in Figure 4 As shown, the left figure is the position comparison of the two penetration area sub-models and the reference surface, and the right figure is its reference surface.

[0071] Furthermore, in the above embodiment, after the sealing process, the step of separating the penetration area of ​​the initial outer layer model to obtain two sub-models includes:

[0072] Determine the collision line of two initial outer layer models, the collision line is a set of line segments on multiple triangular facets; the endpoints of the line segments on the collision line and the vertices on the triangular facets on which they are located inside the other model are combined into a new facet, and the facet is the edge of the penetration area; the new facet and the facet whose three vertices are inside the other model are combined into a new mesh model, and if there are unconnected areas, multiple mesh models are generated.

[0073] Furthermore, in the above embodiment, the method of determining the cutting surface set between the restoration models based on the initial outer layer model of the restoration includes: splitting the initial outer layer model and respectively determining the penetration area mesh sets of the two initial outer layer models; matching the penetration area mesh sets of the two initial outer layer models with the mesh set of the reference surface, and determining the mesh with the smallest distance sum as the matching mesh by calculating the distance sum between the nearest boundary points of the two meshes; and determining the cutting surface set based on the matching meshes.

[0074] First, the vertex set of the current model inside the other model is calculated, and additional vertices that are in the same face as these vertices but outside the other model are added. These vertices are partitioned according to connectivity and separated from the source mesh. The source mesh is then divided into several independent sub-meshes, including a set of meshes in the penetrating area and a set of meshes in the non-penetrating area.

[0075] When splitting the model, you need to record a list of vertices to be smoothed ToFairList for each of the two restoration models, which will be used for the smoothing operation after the model is fused in the subsequent post-processing process. Add the contact edge vertices between the sub-models to ToFairList.

[0076] The penetration area mesh set separated from the two models is matched with the reference surface mesh set. The matching method is to calculate the distance sum between the nearest boundary points of the two meshes. The mesh with the smallest distance sum is the matching mesh.

[0077] At this time, a set of successfully matched mesh sets includes three sub-meshes: the penetration area SubMeshA of the denture model 1, the penetration area SubMeshB of the denture model 2, and the corresponding reference surface RefMesh.

[0078] More specifically, the step of determining the cutting surface set according to the matching grid includes:

[0079] Perform mesh smoothing on SubMesh (SubMeshB, and / or SubMeshB) to obtain a minimum area mesh; perform re-meshing on the vertices in the SubMesh mesh except the boundary vertices to obtain a uniform mesh; calculate the least square surface of the boundary vertices of the SubMesh mesh, and take its normal N; if the SubMesh contains a neck margin line, calculate the neck margin line influence area Rn, Rn includes the vertices in the three neighborhoods of the neck margin line excluding the neck margin line vertex, and the vertices within the radius r of the neck margin line vertex, and the value of r is linearly related to the minimum distance d from the neck margin line vertex to RefMesh; calculate the projection coordinates of each vertex of the above mesh except the Rn area on the reference surface RefMesh with N as the direction, if the projection coordinates can be correctly calculated, move the vertex to this projection coordinate; through the mesh smoothing algorithm, smooth the Rn area with the local minimum curvature change to obtain the cutting surface set.

[0080] Use SubMeshA from the previous step as the cutting surface of denture model 1, and SubMeshB as the cutting surface of denture model 2, and process the cutting surfaces as follows:

[0081] Perform mesh smoothing on SubMesh (SubMeshA or SubMeshB) to obtain the minimum area mesh;

[0082] Re-meshing the vertices of the above mesh except the boundary vertices to obtain a uniform mesh;

[0083] Calculate the least squares surface of the SubMesh mesh boundary vertices and take its normal N;

[0084] If the SubMesh contains the neck line, the neck line influence area Rn is calculated. Rn includes the vertices in the three neighborhoods of the neck line excluding the neck line vertex, and the vertices within the radius r of the neck line vertex. The value of r is linearly related to the minimum distance d from the neck line vertex to RefMesh, and r can be taken as 1.8*d.

[0085] Calculate the projection coordinates of each vertex of the above mesh except the Rn area on the reference surface RefMesh in the direction of N. If the projection coordinates can be calculated correctly, move the vertex to this projection coordinates. Otherwise, ignore it and add it to the above-mentioned set of areas to be smoothed ToFairList.

[0086] Generate the shape of the transition area between the neck edge line and RefMesh: Use the mesh smoothing algorithm to smooth the Rn area with the local minimum curvature change. The mesh obtained at this time is the cutting surface mesh.

[0087] Furthermore, in the above embodiment, the target outer layer is smoothed according to a preset mesh smoothing algorithm, including: determining a set of areas to be smoothed ToFairList, the ToFairList including edge vertices that are in contact with each other between sub-models of the initial outer layer model, and when determining a set of cutting surfaces, outside the Rn area in the SubMesh mesh, vertices whose projection coordinates on the reference surface RefMesh with N as the direction cannot be calculated, the Rn being the neck margin line influence area, and the N being the normal of the least squares surface of the SubMesh mesh boundary vertices; performing smoothing processing with a local minimum curvature change on the set of areas to be smoothed ToFairList.

[0088] Furthermore, based on the above embodiment, a set of non-penetration area grids and a set of cutting surfaces are finally obtained, and the following processing is required later:

[0089] The meshes in these two sets are merged into one mesh, and the outer layer model of the denture after cutting is obtained; the above-mentioned area to be smoothed ToFairList is smoothed with the local minimum curvature change through the mesh smoothing algorithm; the above-mentioned smoothed mesh and the inner layer of the mesh split during the preprocessing in the above embodiment are combined into a new complete mesh model; at this point, the complete denture mesh model after cutting is obtained.

[0090] In a second aspect, the present application also provides a fusion cutting device for a denture restoration, comprising:

[0091] A data acquisition module, used for acquiring at least two restoration models, wherein the restoration models include an inner layer model and an initial outer layer model;

[0092] A preprocessing module, used for preprocessing the restoration model to separate the inner layer model of the restoration model and retain the initial outer layer model of the restoration;

[0093] A first processing module, configured to determine a set of reference surfaces between the restoration models based on an initial outer layer model of the restoration, wherein the reference surfaces belong to the interior of a penetration region between the restoration models;

[0094] A second processing module is used to determine a set of cutting surfaces between the restoration models based on the initial outer layer model of the restoration, wherein the cutting surfaces are used to indicate surfaces of the restorations that are in contact with each other after being cut;

[0095] A third processing module, configured to merge the reference surface set and the cutting surface set to obtain a target outer layer after cutting;

[0096] The fourth processing module is used to perform smoothing processing on the target outer layer according to a grid smoothing algorithm, and combine the smoothed target outer layer with the inner layer model of the restoration model to obtain the restoration model after cutting.

[0097] It should be noted that the above-mentioned fusion cutting device for denture restoration can execute the fusion cutting method for denture restoration provided in the embodiment of the present application, and has the corresponding functional modules and beneficial effects of the execution method. For technical details not fully described in the embodiment of the fusion cutting device for denture restoration, please refer to the fusion cutting method for denture restoration provided in the embodiment of the present application.

[0098] See also Figure 4 , Figure 4 1 is a schematic diagram of the structure of an electronic device 300 provided in an embodiment of the present application. The electronic device 300 includes one or more processors 31 and a memory 32. The memory 32 is connected to the one or more processors 31, for example, connected to the processor 31 through a bus.

[0099] The processor 31 is configured to support the electronic device 300 to perform the corresponding functions in the method in the above method embodiment. The processor 31 can be a central processing unit (CPU), a network processor (NP), a hardware chip or any combination thereof. The above hardware chip can be an application specific integrated circuit (ASIC), a programmable logic device (PLD) or a combination thereof. The above PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL) or any combination thereof.

[0100] The memory 32 is used to store program codes, etc. The memory may include a volatile memory (VM), such as a random access memory (RAM); the memory may also include a non-volatile memory (NVM), such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD); the memory 32 may also include a combination of the above-mentioned types of memory.

[0101] The memory 32 can be used to store non-volatile software programs, non-volatile computer executable programs and modules, such as program instructions / modules corresponding to the fusion cutting method of the denture restoration in the embodiment of the present application. The processor 31 executes various functional applications and data processing of the fusion cutting method of the denture restoration and the fusion cutting device of the denture restoration by running the non-volatile software programs, instructions and modules stored in the memory 32, that is, realizes the functions of each module or unit of the fusion cutting method of the denture restoration and the fusion cutting device of the denture restoration provided by the above method embodiment.

[0102] The memory 32 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created according to the use of the fusion cutting device of the denture restoration, etc. In some embodiments, the memory 32 may optionally include a memory remotely arranged relative to the processor 31, and these remote memories may be connected to the fusion cutting device of the denture restoration via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0103] One or more modules are stored in the memory 32, and when executed by one or more processors 31, the fusion cutting method of the denture restoration in any of the above method embodiments is executed, for example, the method steps described in the above method embodiments are executed to realize the functions of the modules described in the above device embodiments.

[0104] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program. The computer program includes program instructions. When the program instructions are executed by a computer, the computer executes the method of the aforementioned embodiment.

[0105] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0106] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A fusion cutting method for a denture restoration, characterized in that: The method comprises: Acquire at least two restoration models, wherein the restoration models include an inner layer model and an initial outer layer model; Preprocessing the restoration model to separate the inner layer model of the restoration model, retaining the initial outer layer model of the restoration, and the initial outer layer models of different restoration models are in contact with each other to form a penetration area and a non-penetration area; Determining a penetration region and a non-penetration region between the initial outer layer models, and preprocessing the penetration region to obtain a set of cutting surfaces between the initial outer layer models; Merging the cutting surface set and the non-penetration area to obtain a target outer layer after cutting; According to a preset grid smoothing algorithm, the target outer layer is smoothed, and the smoothed target outer layer is combined with the inner layer model of the restoration model to obtain the restoration model after cutting.

2. The method according to claim 1, characterized in that The preprocessing of the penetration area to obtain a set of cutting surfaces between the initial outer layer models includes: Performing a sealing process on the initial outer layer model; After the sealing process, the penetration area of ​​the initial outer layer model is separated to obtain two sub-models of the initial outer layer model respectively; The model with the smaller area among the two sub-models is the target model; Determining a reference surface according to the target model; Based on the reference surface, the set of cutting surfaces is determined.

3. The method according to claim 2, characterized in that The sealing process of the initial outer layer model comprises: Calculate the geometric center coordinates P of the neck edge line in the initial outer layer model and the maximum length L of the grid bounding box; Fitting a least square surface with the coordinates of the vertices of the neck margin line, calculating the normal vector of the least square surface, and taking the direction N facing away from the grid in the positive and negative directions of the normal vector; Insert a new vertex V at the position where point P moves L length along direction N, and its coordinates are P+N*L; The vertex V is respectively combined with every two adjacent vertices of the neck edge line to form a facet, so as to obtain a closed mesh of the initial outer layer model.

4. The method according to claim 2, characterized in that: The step of determining a reference surface according to the target model includes: Determine the minimum area grid of the target model by using a grid smoothing algorithm; The grid is re-gridged to obtain a grid with uniform surface patches as the reference surface.

5. The method according to claim 2, characterized in that: After the sealing process, the penetration area of ​​the initial outer layer model is separated to obtain two sub-models, including: Determine a collision line between two initial outer-layer models, wherein the collision line is a set of line segments on a plurality of triangular facets; The endpoints of the line segments on the collision line and the vertices on the triangular facet where the line segments are located and located inside another model form a new facet, and the facet is the edge of the penetration area; The new facet and the facets whose three vertices are inside another model are combined into a new mesh model. If there are disconnected areas, multiple mesh models are generated.

6. The method according to claim 2, characterized in that The step of determining the cutting surface set based on the reference surface comprises: Splitting the initial outer layer model, and respectively determining penetration area grid sets of two initial outer layer models; Match the mesh sets of the penetration areas of the two initial outer models with the mesh sets of the reference surface, and determine the mesh with the smallest distance sum as the matching mesh by calculating the distance sum between the nearest boundary points of the two meshes. The matching mesh includes the penetration areas SubMeshA and SubMeshB of the two initial outer models, and the corresponding reference surface RefMesh; The cutting surface set is determined according to the matching grid.

7. The method according to claim 6, characterized in that Determining the cutting surface set according to the matching grid includes: Perform mesh smoothing on SubMesh (SubMeshB, and / or SubMeshB) to obtain the minimum area mesh; Re-meshing the vertices other than the boundary vertices in the SubMesh mesh to obtain a uniform mesh of the face; Calculate the least squares surface of the SubMesh mesh boundary vertices and take its normal N; If the SubMesh contains a neck line, the neck line influence area Rn is calculated. Rn includes the vertices in the three neighborhoods of the neck line excluding the neck line vertex, and the vertices within the radius r of the neck line vertex. The value of r is linearly related to the minimum distance d from the neck line vertex to RefMesh. Calculate the projection coordinates of each vertex of the above mesh except the Rn region on the reference surface RefMesh in the direction N. If the projection coordinates can be calculated correctly, move the vertex to this projection coordinates; The Rn region is smoothed with a local minimum curvature change by using a grid smoothing algorithm to obtain the cutting surface set.

8. The method according to any one of claims 1 to 7, characterized in that: The smoothing process of the target outer layer according to the preset grid smoothing algorithm includes: Determine the set of areas to be smoothed ToFairList, wherein ToFairList includes the edge vertices that contact each other between the sub-models of the initial outer layer model, and the vertices whose projection coordinates on the reference surface RefMesh cannot be calculated when N is the direction outside the Rn area in the SubMesh mesh when determining the cutting surface set, wherein Rn is the neck margin line influence area, and N is the normal direction of the least squares surface of the SubMesh mesh boundary vertex; The set of regions to be smoothed ToFairList is smoothed with a local minimum curvature change.

9. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory is connected to the processor, and the processor is used to execute one or more computer programs stored in the memory, and when the processor executes the one or more computer programs, the electronic device implements the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the processor is caused to perform the method according to any one of claims 1 to 7.

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