Three-dimensional model storage, exchange and retrieval method, system and medium

Abstract

The invention relates to a three-dimensional model storage, exchange and retrieval method. The method comprises the following steps: executing a neutral format conversion process of a three-dimensional model; extracting feature information from the three-dimensional model and storing the feature information; analyzing the stored feature information to construct a retrieval index; consistency verification before and after conversion of the three-dimensional model is executed; respectively executing visual format conversion for the three-dimensional model and the neutral format; and executing data exchange, online browsing and retrieval according to an instruction of the user.

Description

Technical Field

[0001] This application relates to the technical field of three-dimensional model storage and utilization. Specifically, it involves a comprehensive method and system that integrates the conversion of neutral formats of three-dimensional models, the consistency verification before and after conversion, the conversion of visualization formats, and online browsing and retrieval. Background Art

[0002] With the rapid development of computer graphics and three-dimensional modeling technologies, the MBD technology (also known as digital product definition technology) has become the main technical means for industrial product design and manufacturing. The MBD technology uses a single three-dimensional model of the product to completely express and display product definition information, which includes product dimensions, tolerances, processes, etc. The three-dimensional model has become the sole basis in the processes of industrial product design, simulation analysis, production manufacturing, test verification, customer service, etc. However, due to the problem of format incompatibility between different industrial software platforms, many challenges have been caused in the storage, exchange, and retrieval and utilization of three-dimensional models.

[0003] In the prior art, most use single-format storage and exchange, which not only limits the compatibility of the model but also increases the complexity of subsequent processing. In addition, problems such as data loss or deformation may occur during the conversion of three-dimensional models, affecting the model quality. Although some improvement solutions have been proposed by technical personnel for these problems, these solutions can only solve some of the above problems and cannot provide a complete set of solutions for the storage, exchange, and retrieval of three-dimensional models.

[0004] For example, in the patent document with the publication number CN117235015A (application number: CN202311147437.3), a big data retrieval method and system based on the association of three-dimensional models and documents are disclosed. It also proposes a big data retrieval method and system based on the association of three-dimensional models and documents, including: converting the original format three-dimensional model file into a neutral format three-dimensional model file, and generating an archive information package after successful conversion; performing lightweight processing on the archive information package to generate a dissemination information package of the lightweight model file and distributing it to users; importing the model attributes in the archive information package into the configuration management database for storage and management to establish the device information configuration relationship; initializing and establishing an index table, traversing and retrieving the documents in the document system, and establishing an index table for the metadata information and document content of the documents based on the device configuration information; users can browse the three-dimensional model based on the dissemination information package and view the device configuration information to retrieve the documents that match the index words in the document system. Its solution associates the three-dimensional model with various types of files in the document system, improving the data utilization efficiency of the three-dimensional model and reducing the workload of technical personnel and document personnel.

[0005] However, the solution in the patent document does not disclose how to maintain / verify the consistency between the original format 3D model file and the converted neutral format 3D model file. As mentioned above, problems such as data loss or deformation may occur during the conversion of 3D models, affecting the model quality. Therefore, in the said conversion, a consistency detection mechanism is needed to avoid problems such as data loss or deformation, so as to improve the quality of model conversion. However, the patent document does not disclose relevant content.

[0006] In addition, the patent document discloses that by traversing and retrieving the documents in the document system, an index table is established for the metadata information and document content of the documents, and this index table is used to provide data retrieval. However, the disclosed retrieval method is mainly based on a single information source, namely device information configuration information, lacking sufficient data support. Therefore, the said index table can only provide limited document retrieval functions and cannot provide a more comprehensive and powerful data retrieval solution.

[0007] Therefore, there is a need in the industry to provide a complete set of 3D model storage, exchange and retrieval solutions for realizing long-term, efficient, safe and compatible storage, exchange and utilization of 3D models. Summary of the Invention

[0008] The purpose of this application is to establish a comprehensive solution that integrates neutral format conversion of 3D models, consistency verification before and after conversion, visualization format conversion, and online browsing and retrieval, so as to realize data storage, format conversion, data exchange and data reuse of 3D models.

[0009] According to the first aspect of this application, a method for 3D model storage, exchange and retrieval is provided, including:

[0010] Execute the neutral format conversion process of the 3D model;

[0011] Extract feature information from the 3D model and store it;

[0012] Analyze the stored feature information to construct a retrieval index;

[0013] Execute the consistency verification before and after the 3D model conversion;

[0014] Execute visualization format conversion for the 3D model and the neutral format respectively; and

[0015] Execute data exchange, online browsing and retrieval according to the user's instructions.

[0016] According to the second aspect of this application, a computer-readable storage medium is provided, on which computer instructions are stored, and when the computer instructions are executed by a processor, the 3D model storage, exchange and retrieval method described in the first aspect is executed.

[0017] According to a third aspect of the present application, there is provided a three-dimensional model storage, exchange and retrieval system, including a device for executing the three-dimensional model storage, exchange and retrieval method as described in the first aspect.

[0018] This summary is provided to introduce in a simplified form some concepts that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To describe the manner in which the above and other advantages and features of the present invention can be obtained, a more specific description of the present invention briefly described above will be presented by reference to specific embodiments of the present invention shown in the accompanying drawings. It is understood that these drawings only depict typical embodiments of the present invention and are therefore not considered to limit its scope. The present invention will be described and explained by using the drawings and by means of additional features and details, in which:

[0020] Figure 1 A schematic flowchart of a method for storing, exchanging and retrieving a three-dimensional model according to an embodiment of the present application is shown.

[0021] Figure 2 A schematic diagram of information elements of a CAD electronic file related to parts according to an embodiment of the present application is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] As described in the background art section, the existing three-dimensional model storage, exchange and retrieval technologies mainly have the following problems:

[0023] a) Single-format storage: Most of the existing technologies store three-dimensional models in a single format, which cannot support high-quality exchange and online browsing of models at the same time, restricting the compatibility and scalability of the models;

[0024] b) Lack of comparison before and after conversion; The existing consistency check mainly focuses on the differences between the original models of different three-dimensional model design platforms, and does not perform consistency check on the original three-dimensional model and the converted neutral format, resulting in great risks in data exchange and data reuse;

[0025] c) Single retrieval method: The existing three-dimensional model retrieval methods are relatively single, and it is difficult to make full use of the feature information of the model itself, resulting in low retrieval accuracy and poor reusability.

[0026] To overcome the above problems, this application proposes a comprehensive solution that integrates the neutral format conversion of 3D models, consistency verification before and after conversion, visualization format conversion, and online browsing and retrieval, in order to achieve data storage, format conversion, data exchange, and data reuse of 3D models.

[0027] Generally speaking, as Figure 1 shown, the 3D model storage, exchange, and retrieval solution of this application can include five main steps.

[0028] Step 1: Start the neutral format conversion process of the 3D model. That is, through this step, the original 3D model is converted into a neutral format, such as a.stp file.

[0029] The neutral format conversion of 3D models refers to the process of converting proprietary file formats generated by different 3D modeling software into a cross-platform, standardized, and software-independent general format. This conversion aims to solve compatibility problems between different software and ensure the lossless transfer of model data (geometric structure, materials, animations, etc.) across different tools, platforms, or workflows.

[0030] Among them, the definition of the neutral format is: a non-proprietary, open-standard 3D file format that does not depend on specific software and supports cross-platform collaboration. Typical formats include STEP (.stp), IGES (.igs) in the field of industrial design; OBJ (.obj), FBX (.fbx), Collada (.dae), glTF (.glb), etc. in general 3D models. As an example, in this application, the neutral format of the.stp format is adopted. However, it should be understood that for different application scenarios, other formats can also be applicable to the solution of this application, not limited to the.stp format.

[0031] Specifically, the neutral format conversion method of the 3D model in the embodiments of this application is based on the interface program provided by the CAx system, that is, by calling SDAI functions and local format access functions (APIs) for necessary calculations to convert the original 3D model into a neutral format for compatibility and exchange on different software platforms or application environments.

[0032] The first step of the neutral format conversion process of the 3D model includes the following sub-steps:

[0033] Step 1.1: When converting the original 3D model, it is necessary to load the assembly and the corresponding sub-parts into the temporary directory.

[0034] Step 1.2: Reorganize the 3D model data (i.e., assemble the components of the model into assemblies, involving data processing such as deduplication and version verification during this process), rename the temporary directory with the name of the original 3D model, and then notify the model conversion service of the location information of the temporary directory.

[0035] Step 1.3: Start the model conversion service, select the target neutral format, and execute the conversion algorithm.

[0036] Step 1.4: Output the converted neutral format file and automatically attach it to the corresponding original 3D model entry, and at the same time delete the temporary directory.

[0037] In this way, the original 3D model can be converted into a neutral format, which is a.stp format file in this embodiment. However, as described above, the neutral format file generated in this way may not actually be completely consistent with the original 3D model. For example, data loss or deformation (such as loss of model textures or assembly relationships), damage to geometric integrity, and reduction in accuracy may occur during the conversion of the 3D model. Therefore, the converted neutral format file is not suitable for direct use and also needs to go through the following consistency verification process steps before and after conversion.

[0038] In other words, referring to Figure 1 , when the neutral format conversion process of the 3D model is completed, this method enters Step 2. In order to perform the consistency verification before and after the 3D model conversion, it is necessary to first execute Step 2 of extracting the feature information from the (original) 3D model and storing it.

[0039] In Step 2, execute the process steps of extracting the feature information of the 3D model and storing it. Although this process step is listed as Step 2, it should be understood that there is no strict sequence between the extraction Step 2 and the previous conversion Step 1. That is to say, the feature information can be extracted first, and then the neutral format conversion of the 3D model can be executed, or these two steps can be executed simultaneously, which are all within the protection scope of this application.

[0040] Specifically, the said Step 2 may specifically include the following sub-steps:

[0041] Step 2.1: Load the original 3D model.

[0042] The original 3D model is usually provided in the form of a CAD electronic file. Of course, other file formats in addition to the CAD electronic file form can also be used as the file type of the original 3D model. Here, the CAD electronic file is only given as an example, and the actual application is not limited to this.

[0043] Step 2.2: Extract the feature attributes from the loaded original 3D model and form an XML file.

[0044] Generally speaking, the characteristic attributes of a 3D model can be divided into two categories: geometric attributes and non-geometric attributes, which specifically include the following:

[0045] 1. Geometric attributes, including:

[0046] a. Geometric topology attributes

[0047] The geometric topology attributes of the product include entity model geometric information such as GVP values (volume, area, centroid) and point clouds.

[0048] b. Product structure tree

[0049] The product structure tree is actually an assembly relationship between components and parts. Specifically, a 3D model is composed of basic geometric elements such as points, lines, and planes, and its shape is jointly defined by geometric data (such as vertex coordinates, normal vectors) and topological relationships (such as the connection methods of edges and faces).

[0050] The topological structure may change dynamically due to parameter adjustment. For example, the increase or decrease of a certain feature in the model (such as the change in the number of washbasins) will change the overall topological relationship.

[0051] Therefore, in order to build the geometric structure tree of a 3D model, first, it is necessary to extract the assembly relationship between each part and other components from the 3D model.

[0052] Then, for example, the framework structure of the ATA chapter can be combined with BOM (Bill of Materials) technology to build the geometric structure tree.

[0053] For example, in the field of the aviation industry, there is a close collaborative relationship between the ATA chapter and the BOM structure. The two jointly support the product life cycle management through standardized coding and structured data. In the application of 3D models, the ATA chapter usually refers to the standardized classification system of aircraft systems or components. Its core role is to achieve structured design of 3D models, association of technical documents, and integration of maintenance processes through a unified coding specification.

[0054] Specifically, the ATA chapter provides standardized classification codes for aircraft systems (such as the ATA 21 air conditioning system, ATA 32 landing gear). These codes can be directly mapped to the top-level structure of the BOM to form the core framework of the EBOM (Engineering Bill of Materials). For example, the system modules divided by the ATA chapter (such as the ATA 28 fuel system) correspond to the parent nodes of the BOM, and its sub-modules (fuel tank, fuel pump) are gradually expanded through the parent-child relationship of the BOM to form a multi-level BOM structure. In addition, the assembly logic marked by the ATA chapter in the 3D model (such as the electrical topology of the ATA 24 power system) can be converted into the "usage relationship" in the BOM to clarify the assembly dependencies between components.

[0055] In this way, when the user clicks on a part at a certain level in the BOM structure, they can trace up to the model of the associated upper-level component and retrieve the models of the associated sub-components downwards. Thus, a complete geometric structure tree of an aircraft system (such as an air conditioning system or a braking system) can be constructed using the multi-level BOM structure based on the ATA chapter. Among them, each node (there may be hundreds or thousands of nodes) in the geometric structure tree corresponds to the data model file of the corresponding part in the system, and they are topologically distributed in different node levels in the structure tree according to their superior-subordinate relationships in the system. Therefore, when the user selects one of the nodes, the data model files of the parts at the upper and lower levels of this node are also clearly shown, so as to realize the retrieval and traceability of the data models of the selected part and the associated parts in the system.

[0056] 2. Non-geometric attributes

[0057] a. Basic information

[0058] It includes information such as name, part type, symmetric part identifier, critical part type, copyright statement, higher-level description, and change code.

[0059] b. Engineering notes

[0060] Engineering 3D models may also contain attributes related to manufacturing processes, specifications, parameters, or simulation requirements.

[0061] c. Material information

[0062] It includes the materials / material qualities used for the part and the texture, and the texture includes surface attributes such as color, texture map, and reflectivity, which are covered on the geometric model through texture mapping technology to enhance the realism.

[0063] Some models also contain advanced material attributes such as normal map and transparency.

[0064] d. Flag note information

[0065] Flag notes (such as small flag icons) usually represent the annotation or note marks in the model, used to identify areas or technical descriptions that require special attention.

[0066] e. Custom attributes

[0067] Since each company and enterprise has different personalized requirements for 3D models, custom attributes are provided to meet the customization needs of these third parties. Customers can customize new attributes according to their own needs.

[0068] f. PMI information (dimensions and spatial relationships)

[0069] The PMI (Product and Manufacturing Information) of a model refers to the manufacturing and inspection specification information directly embedded in a 3D model, mainly including the dimensional and spatial relationships of the product. Among them, the dimensions are achieved through parametric constraints (such as stretching length, chamfer radius) or geometric transformations (such as rotation, scaling). The spatial relationships between features are defined by contexts such as sketch planes and assembly positions, for example, the combined relationship between a wheel and a vehicle body.

[0070] As an example, Figure 2 provides a schematic diagram of information elements of a CAD electronic file of an example part. And, Table 1 shows an example entity metadata table of feature attributes associated with the above CAD electronic file.

[0071]

[0072]

[0073]

[0074] Table 1. Example of entity metadata of feature attributes of a 3D model electronic file

[0075] As Figure 2 and shown in Table 1, in the CAD electronic file of the example and the associated entity metadata table, the "feature attributes" include GVP values (volume, area, center of gravity), material information, flag note information, custom attributes, engineering notes, etc. It should be understood that Figure 2 the data shown in and Table 1 are only given as examples, and it does not mean that the feature attributes are limited to this. Depending on the objects involved in the 3D model, the feature attributes to be extracted are also different.

[0076] After extracting the above-mentioned feature attributes from the original 3D model, an XML file is formed based on the extraction results and stored under the corresponding original 3D model entry. In this way, the extracted feature attributes are saved separately in the form of an XML file for further processing.

[0077] It should be understood that although the most common XML file form is adopted here to store the feature attributes. But this is only for illustrative purposes and is not intended to be limited to this file format. Those skilled in the art can understand that other suitable file formats can also be used to save the feature attributes.

[0078] Compared with only extracting the "device information configuration information" in the previously mentioned patent document (CN117235015A), the characteristic attributes of this application not only include more comprehensive characteristic information, but also can achieve more abundant functions. For example, the data model traceability retrieval of the above-mentioned associated parts, and the consistency detection to be further described below.

[0079] After creating and storing the XML file including the characteristic attributes, this method proceeds to step 3.

[0080] Step 3: Parse the stored (stored in the XML file) characteristic attributes to build a retrieval index, that is, parse the XML file storing the characteristic attributes, and build a retrieval index based on the characteristic attribute information and store it in the database.

[0081] The above step specifically includes the following sub-steps:

[0082] Step 3.1: Data preprocessing.

[0083] Perform preprocessing operations on the XML document such as redundant tag filtering (such as comments, empty nodes), coordinate transformation, unit unification, unified tag naming, data chunking, etc.

[0084] Step 3.2: Extract and analyze characteristic attributes.

[0085] For each characteristic attribute, distinguish numerical attributes (such as size coordinates, scaling factors) from text attributes (such as material names, comments), and establish structured field and unstructured field indexes for them respectively;

[0086] Parse the XML attributes of each characteristic attribute (such as id and type in <mesh id="M1"type="polygon">) as metadata tags to enhance the retrieval semantic relevance.

[0087] Subsequently, structure and vectorize each characteristic attribute.

[0088] Step 3.3: Build a retrieval index according to the index strategy.

[0089] When building the index, the available index strategies include various strategies such as geometric space index, inverted index, and hybrid index optimization, among which:

[0090] Geometric space index: Use an R-tree or octree to encode the model bounding box and spatial hierarchical structure, supporting fast range queries (such as "finding all components within a certain coordinate range"). For example, the frame structure of the ATA chapter described above combined with the BOM technology can be used to build the geometric space index.

[0091] Inverted index: Establish a keyword-document mapping table for text attributes such as material and texture tags. For example, "metal material" is associated with all model files containing <material category="metal">.

[0092] Hybrid index optimization: Combine inverted index and spatial index to achieve multi-condition joint query. For example, "retrieve 3D form models with glass material and height > 2 meters".

[0093] In addition, adopting a batch parsing and asynchronous loading strategy can improve the processing efficiency of large-scale model libraries.

[0094] Step 3.4: Retrieve relevant information based on the retrieval index.

[0095] After constructing the retrieval index for feature attributes, the constructed retrieval index can be used to retrieve relevant information. For example, according to the query information or other conditions input by the user, use the retrieval index to search and retrieve relevant information in the corresponding data structure.

[0096] The retrieval can include two aspects. First, it is the retrieval of relevant documents. For example, a user may need to retrieve parts containing a specific metal material (such as chromium) in all 3D models. In this way, as long as he enters relevant query conditions in the search interface, he can easily retrieve the parts related to the material attribute "chromium" and their specific information. Another retrieval is the data model retrieval as described above. Since a complete product geometric structure tree can be constructed based on the extracted feature attributes, the user can directly retrieve the data model files of the upper and lower layer parts associated with a certain part node in the geometric structure tree for convenient maintenance.

[0097] Step 4. Perform consistency verification before and after the 3D model conversion.

[0098] Consistency verification mainly refers to whether the key content information of the model changes during the conversion of the original 3D model into a neutral data format, which can provide an important reference for data exchange and data reuse.

[0099] As mentioned above, problems such as data loss or deformation may occur during the conversion of 3D models into a neutral data format, affecting the quality of the converted model. Therefore, it is necessary to provide consistency verification before and after the conversion, which is a key link to ensure the accuracy of geometric, attribute, and logical relationships of the model during different platform or format conversions and needs to be achieved through multi-level technical means.

[0100] Specifically, Step 4 can specifically include the following sub-steps:

[0101] Step 4.1: Extract the feature attributes from the neutral format (i.e., the neutral format file generated after conversion) and store them as corresponding XML files (the feature extraction and storage of the original 3D model have been completed in Step 2). As mentioned above, the feature attributes may include the geometric structure tree attributes, geometric topology attributes, PMI information, engineering annotations, custom attributes, etc. of the product;

[0102] Step 4.2: Configure the corresponding verification items and verification rules based on the application field.

[0103] The configuration of the verification items and verification rules can refer to the custom configuration thresholds of the relevant standards in this field. Specifically, the configuration of the verification items and verification rules needs to be closely combined with the industry standards and business requirements of each field. Based on different application fields, it is necessary to configure the corresponding verification items and verification rules. In the engineering field, for example, in civil engineering, the verification items may include engineering structure strength, material specifications, etc., and the verification rules can refer to the engineering structure design standards, and set custom configuration thresholds according to different building types and load requirements to verify whether the structure is safe and reliable; in electrical engineering, for the verification of circuit parameters, electrical equipment performance, etc., reasonable ranges of parameters such as voltage and current need to be set according to the electrical industry standards. For the manufacturing field, the quality inspection of the produced products is the focus. For example, the dimensional accuracy and surface roughness of parts in mechanical manufacturing are verification items, and the form and position tolerances, roughness grades, etc. are customized according to the industry specifications of mechanical manufacturing for verification; for electronic product manufacturing, the parameters of electronic components, circuit board wiring, etc. need to be verified, and the verification rules are determined by referring to the relevant standards of the electronics industry. This application can achieve precise control through dynamic threshold setting, rule templatization management, and automated verification mechanisms.

[0104] Step 4.3: Load the corresponding feature attributes (also called verification attributes) before and after conversion from the XML file of the feature attributes of the 3D model and the XML file of the feature attributes of the neutral format respectively, and perform consistency verification calculations.

[0105] The consistency verification may include the following aspects:

[0106] 1. Integrity verification, for example, verifying the integrity of the system structure by comparing the geometric structure attributes of the product before and after conversion to check whether there are missing components;

[0107] 2. Attribute mapping verification: By comparing the metadata of the model before and after conversion (such as material specifications, dimensional parameters), ensure that non-geometric attributes (such as BOM information) are not lost or tampered with;

[0108] 3. Coding rule check: Verify whether the standardized codes such as ATA chapter numbers and part identifiers before and after conversion are completely inherited to avoid identification errors caused by format differences;

[0109] 4. Assembly Hierarchy Verification: Verify whether the parent-child assembly relationship (such as the connection between the landing gear and the braking device) maintains the original hierarchical structure after conversion; and

[0110] Other types of verification.

[0111] Table 2 shows example items of consistency verification and the verification attributes required for each item.

[0112] It should be understood that the categories and verification attributes shown in Table 2 are only for illustrative purposes and are not intended to be limiting.

[0113]

[0114] Table 2 Consistency Verification Items

[0115] Step 4.4: Generate a consistency verification report based on the verification results and store it under the corresponding original 3D model entry.

[0116] If the consistency verification fails, the technician can find the reason by analyzing the consistency report. Subsequently, by adjusting the corresponding configurations and parameters, the neutral format conversion and consistency verification process of the 3D model are executed again until the user requirements are met.

[0117] After the conversion passes the consistency verification, the process of the method can execute the visualization format conversion step 5.

[0118] Visualization format conversion refers to converting model data into a visualization expression form suitable for different platforms through data format optimization, rendering process reconstruction, and interaction logic adaptation, which mainly solves the defect that 3D models and neutral formats cannot be browsed online. Many corresponding visualization tools have been developed in the existing field. In this application, the visualization format conversion is mainly achieved through the CMCenter background conversion software, using the asynchronous call interfaces of Pro / E (Creo), Solidworks, UG NX, CATIA, and Autodesk Inventor. The step 5 may include the following sub-steps:

[0119] Step 5.1: Load the original 3D model and the neutral format into a temporary directory.

[0120] Step 5.2: Rename the temporary directory with the name of the 3D model, and then notify the model conversion service of the location information.

[0121] Step 5.3: Start the model conversion service, select the target visualization format, and execute the visualization format conversion process of the 3D model and the neutral format respectively through the various interfaces in the CMCenter software.

[0122] The configurations and definitions of each interface of the CMCenter software are as follows:

[0123] Pro / E (Creo): Provides parametric data parsing function. Supports asynchronous export of STEP format files through the ipem_creo_batch command-line tool, fully retaining parametric modeling features (such as constraint relationships, assembly levels). And can verify the model integrity through the ACIS geometric kernel and repair the broken surface problems caused by cross-software conversion.

[0124] SolidWorks: Provides direct reading of cross-format data. Directly parses CATIA V5 and Inventor files by enabling the 3D Interconnect function, eliminating the need for neutral format conversion and reducing the risk of data loss. Supports semantic conversion of sheet metal design features (such as bend radius, unfolded drawing). Provides lightweight output. When exporting the GLB format through swbatch.exe, it automatically merges duplicate material textures, reducing the rendering load on the Web side.

[0125] UG NX: Provides complex geometry processing, including: calling the NX Open API script to export the Parasolid X_T format, retaining synchronous modeling features (such as history-independent geometric editing operations). Optimizes the semantic recognition of injection molding structure features (such as sliders, cooling channels) for the mold industry.

[0126] Execute large model chunking processing: Supports chunked export of the JT format. Combined with the LOD generation algorithm of CMCenter, it adapts to the visualization of ultra-large-scale assemblies.

[0127] CATIA: Calls the CAA V5 Automation interface to generate a neutral format (such as 3DXML), retaining the material and hierarchical structure. Retains precision surfaces, that is, generates a 3DXML neutral format through the CAA V5 Automation interface to ensure G3 / G4 level surface continuity (the core requirements of the aviation and automotive industries). Provides custom attribute mapping rules for special structures such as composite laminates.

[0128] Autodesk Inventor: Provides engineering drawing correlation. Synchronously associates the engineering drawing (DWG format) when exporting the IPT file, supporting the linked viewing of 3D models and 2D drawings on the Web side. Provides lightweight optimization. For the unique iLogic rules of Inventor, they are converted into JSON metadata and embedded in 3D Tiles, retaining the traceability of the design logic.

[0129] Through the above interface functions, CMCenter realizes the full-link data compatibility from the design end to the visualization end, meeting the accurate expression and efficient interaction requirements of complex industrial scenarios.

[0130] Similarly, there may be errors in the above visualization format conversion. Therefore, a quality verification mechanism can also be configured, such as the following steps:

[0131] Step 5.4: Perform conversion quality verification, including:

[0132] Geometric accuracy comparison: Invoke the deviation analysis module of CMCenter Viewer to compare the Brep differences between the original 3D (CAD) model and the converted 3D Tiles (for example, a threshold can be set).

[0133] Attribute integrity: Verify the lossless transfer of PMI (Product Manufacturing Information) and custom attributes.

[0134] In this way, the quality and usability of the visualization format file can be guaranteed.

[0135] Step 5.5: Output the visualization format files after two conversions (the visualization format conversion of the original 3D model and the visualization format conversion of the neutral format), and automatically attach them to the corresponding original 3D model entries, and at the same time delete the temporary directory.

[0136] After performing the above visualization format conversion, in Step 6, data exchange, online browsing, and retrieval can be realized using the generated visualization format file according to the user's instructions. Step 6 may include the following sub-steps (or functions):

[0137] Step 6.1: Data exchange. The neutral format file formed in Step 1 of the above solution can be used as the object of data exchange; at the same time, the consistency check formed in Step 4 of the above solution can help users provide reference when exchanging and reusing the neutral format.

[0138] Step 6.2: Online browsing. The visualization format formed in Step 5 of the above solution can help users browse the original 3D model and the neutral format online. The visualization browsing interface can display the design view hierarchical structure and the 3D model, and they can be mutually selected. The selected model or node is highlighted. Different levels of the design view can be expanded and collapsed. The sorting and grouping of the structure tree are consistent with the original 3D model. The selected 3D model can be zoomed in, zoomed out, and rotated. The PMI information of the 3D model can also be displayed through advanced retrieval.

[0139] Step 6.3: Diversified retrieval. The XML file of feature attributes formed in Step 2 of the above solution can be used to build a retrieval index to support diversified retrieval. Users can perform online retrieval within the scope of their permissions by inputting or selecting different retrieval items. The retrieved data entries can view the detailed information of each part. The retrieval methods mainly include unified retrieval, navigation retrieval, advanced retrieval, and full-text retrieval:

[0140] Unified Search: The user enters keywords, and the system automatically matches according to the basic attributes of the 3D model, and displays the data that meets the search keyword requirements in the form of a list;

[0141] Navigation Search: Based on the product entity architecture, navigate and search according to the component structure tree. Clicking on each level of the node can display the model data corresponding to the current node and all its sub-nodes;

[0142] Advanced Search: Advanced search users can select search fields to implement logical matching operations and combined searches of different attributes.

[0143] Full-Text Search: An index library is established uniformly for all attributes including feature attributes. Users do not need to specify attribute fields, and only need to meet the search keywords to obtain the search result list.

[0144] Example Application

[0145] To better understand the solution of this application, take a civil aircraft R & D unit as an example scenario to describe the implementation instance process of the described solution:

[0146] Phase 1: Data Object Acquisition and Storage

[0147] a) Manually create or import the product structure tree through EXCEL;

[0148] b) Manually create or obtain the same database table structure, user information, organization information, and permission information as the original data storage platform through the Webservice / HTTP protocol interface;

[0149] c) Obtain the 3D model source data from the original data storage platform through the interface. Among them, the entry data interface transmits the attribute information of the 3D digital model, and the full-text data interface transmits the original digital model file of the 3D digital model.

[0150] Phase 2: Format Conversion

[0151] a) Set up a scheduled task, and the system background schedules to convert the assembly and its sub-parts into neutral formats and visualization formats respectively and store them under the corresponding original 3D model entries;

[0152] b) Users can also complete the real-time conversion of the two formats by manually clicking the conversion button.

[0153] Phase 3: Consistency Check

[0154] a) Extract the feature attributes of the original 3D digital model and save them as an XML file, which is one of the important data sources for 3D model data retrieval;

[0155] b) Combine the actual business of the unit to configure the consistency check attributes and thresholds

[0156] c) Extract the verification attributes of the neutral format file after conversion and verify and compare them one by one with the original model. The comparison results are output as a consistency verification report.

[0157] d) After the 3D model is converted to the neutral format, the consistency verification tool is automatically triggered for background conversion. At the same time, the user can also perform real-time conversion through the foreground function key. The output consistency verification report is an important basis for data reuse.

[0158] Phase 4: Retrieval, Utilization, and Browsing

[0159] a) The user can query the target file through unified retrieval, navigation retrieval, advanced retrieval, and full-text retrieval. The retrieval result page includes all attribute information of the 3D digital model, as well as all full-text information including "original format + neutral format + visualization format + feature attribute XML + consistency verification report".

[0160] b) The retrieved neutral format and visualization format support online general browsing and advanced browsing. The original file can be applied for online utilization and downloaded to the local for browsing after approval.

[0161] c) The browsing and downloading permissions of the user can take the union of the four dimensions of role, department, user, and position.

[0162] Phase 5: System Management and Maintenance

[0163] a) The system administrator can perform library table definition and maintenance of the component structure tree through the template classification definition and product structure management modules.

[0164] b) Through the log management module, the situation of interface data reception and user browsing and downloading can be grasped in a timely manner.

[0165] It should be understood that the above examples are only for explaining an application scenario of the solution of the present application, but are not limited to this scenario.

[0166] In addition, the solution of the present application also provides a computer-readable storage medium, on which computer instructions are stored, and when the computer instructions are executed by a processor, each step in the above method is implemented.

[0167] Furthermore, the solution of the present application also provides a 3D model storage, exchange, and retrieval system, including a device for executing the method as described above.

[0168] While the foregoing describes various embodiments, it is to be understood that they are presented by way of example and not limitation. Those skilled in the relevant art will appreciate that various modifications may be made in form and detail without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, the breadth and scope of the invention disclosed herein should not be limited by the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents.

Claims

1. A method for three-dimensional model storage, exchange, and retrieval, including: Performing a neutral format conversion process for the three-dimensional model; Extracting feature information from the three-dimensional model and storing it; Parsing the stored feature information to construct a retrieval index; Performing consistency verification before and after the three-dimensional model conversion; Performing visualization format conversion for the three-dimensional model and the neutral format respectively; And Performing data exchange, online browsing, and retrieval according to the user's instructions.

2. The method according to claim 1, wherein The step of extracting feature information from the three-dimensional model and storing it includes: Loading the three-dimensional model; and Extracting feature attributes from the loaded three-dimensional model and storing them as an XML file; Wherein, the feature attributes include: geometric attribute information including product structure tree attributes, geometric topology attributes, and PMI information, and non-geometric attribute information including basic information and engineering annotations.

3. The method according to claim 1, wherein The step of parsing the stored feature information to construct a retrieval index includes: Performing data preprocessing; Extracting and analyzing the feature attributes; Constructing a retrieval index according to the indexing strategy; and Retrieving relevant information based on the retrieval index.

4. The method according to claim 2, wherein The step of performing consistency verification before and after the three-dimensional model conversion includes: Extracting feature attributes from the neutral format and storing them as corresponding XML files; Configuring corresponding verification items and verification rules based on the application field; Loading the corresponding feature attributes before and after conversion from the XML file of the feature attributes of the three-dimensional model and the XML file of the feature attributes of the neutral format respectively, and performing consistency verification calculations; Generating and storing a consistency verification report based on the verification results.

5. The method according to claim 2, characterized in that, The consistency verification includes the following aspects: Integrity verification, verifying the integrity of the system structure by comparing the product geometric structure attributes before and after conversion, whether there are missing components; Attribute mapping verification: ensuring that non-geometric attributes are not lost or tampered with by comparing the metadata of the model before and after conversion; Coding rule check: verifying whether the standardized coding of the ATA chapter number and component identifier before and after conversion is completely inherited to avoid identification errors caused by format differences; Assembly level verification: verifying whether the parent-child assembly relationship remains the original hierarchical structure after conversion.

6. The method according to claim 1, wherein The step of performing visualization format conversion for the three-dimensional model and the neutral format respectively includes: Loading the three-dimensional model and the neutral format into a temporary directory; Renaming the temporary directory with the name of the three-dimensional model, and then notifying the model conversion service of the location information; Starting the model conversion service, selecting the target visualization format, and performing the visualization format conversion process for the three-dimensional model and the neutral format respectively through each interface in the CMCenter software; Performing conversion quality verification; and Outputting the converted visualization format file and automatically attaching it to the corresponding three-dimensional model entry, and deleting the temporary directory at the same time.

7. The method according to claim 6, wherein The step of performing conversion quality verification includes: Geometric accuracy comparison: calling the deviation analysis module of the CMCenter Viewer to compare the difference between the original three-dimensional model and the Brep of the 3D Tiles after conversion; Attribute integrity: verifying the lossless transfer of PMI and custom attributes.

8. The method according to claim 1, characterized in that, The steps of performing the neutral format conversion process of the 3D model include: When converting the 3D model, load the assembly and the corresponding sub-parts into a temporary directory; Reorganize the 3D model data, rename the temporary directory with the name of the 3D model, and notify the model conversion service of the location information of the temporary directory; Start the model conversion service, select the target neutral format, and execute the conversion algorithm; Output the converted neutral format file and automatically attach it to the corresponding 3D model entry, and at the same time delete the temporary directory.

9. A computer-readable storage medium, on which computer instructions are stored, and when the computer instructions are executed by a processor, the method described in any one of claims 1-8 is executed.

10. A system for 3D model storage, exchange and retrieval, comprising means for executing the method described in any one of claims 1-8.

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