A method and system for assembling CAD parts

Abstract

The present disclosure provides a CAD part assembly method and system, and relates to the technical field of CAD development, which comprises defining a data model and an abstract model of PDM basic data; defining various assembly rules of parts, obtaining lower-level sub-assembly parts allowed to be assembled onto the parts and upper-level assembly parts that can be assembled; obtaining parent-child relationships between the parts and positioning parent-child relationships between the parts, defining expressions related to the sizes of the parts, storing the assembly relationships between the parts, according to the sub-components corresponding to the assembly relationships, referencing the assembly nodes in a tree structure according to the positioning relationships between the assembly nodes, maintaining the positioning relationships between the assembly nodes, and realizing standardized part assembly according to the positioning relationships between the assembly nodes.

Description

Technical Field

[0001] This disclosure relates to the field of CAD development technology, specifically to a CAD part assembly method and system. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] Computer-aided design (CAD), as a crucial link in the entire digital intelligent manufacturing process, drives the development of the entire intelligent manufacturing industry through technological advancements. Assembly modules are key functional modules in CAD software; their user-friendliness impacts the designer's design efficiency and experience. Reasonable functional planning can effectively prevent human error. With the advancement of digitalization and standardization, various industry standards are constantly being introduced, and the reuse rate of parts that meet these standards is continuously increasing. Currently, most commercially available CAD software uses parts libraries or parts import to achieve the reuse of standard parts. However, the system's own functionality has limited support for industry standards, often requiring designers to perform additional operations to achieve standardized assembly.

[0004] Currently, most general-purpose CAD software only supports industry standards in terms of standardized modeling, standardized parts libraries, and the import of standard parts, ensuring that the component model construction itself conforms to industry standards. However, it does not adequately address the requirements of industry standards regarding assembly, positioning, and dimensional relationships. Designers must consult relevant industry standards and perform unnecessary calculations when designing assembly components, thus impacting design efficiency. Summary of the Invention

[0005] To address the aforementioned issues, this disclosure proposes a CAD parts assembly method and system. It abstracts industry standards using an object-oriented approach, rationally plans the functions of the CAD software assembly module, and optimizes standardized assembly operations.

[0006] According to some embodiments, the present disclosure adopts the following technical solutions:

[0007] A CAD part assembly method, comprising:

[0008] Define the data model and abstract model of PDM basic data;

[0009] Define various assembly rules for a part, and obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the part, as well as the upper-level assembly parts that can be assembled.

[0010] Obtain the parent-child relationship between parts in assembly and the parent-child relationship between parts in positioning. Define the expression for the association between part dimensions. Use the unit assembled in the assembly environment as the assembly node. Store the assembly relationship between parts. According to the assembly relationship, the child component of the assembly relationship is corresponding to the assembly relationship. The assembly node is referenced in a tree structure according to the positioning relationship between the assembly nodes. Maintain the positioning relationship between the assembly nodes. Implement standardized part assembly according to the positioning relationship between the assembly nodes.

[0011] According to some embodiments, the present disclosure adopts the following technical solutions:

[0012] A CAD parts assembly system, comprising:

[0013] The basic model module is used to define the data model and abstract model of the PDM basic data;

[0014] The server is used to define various assembly rules for parts, and to obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the parts, as well as the upper-level assembly parts that can be assembled.

[0015] Obtain the parent-child relationship between parts in assembly and the parent-child relationship between parts in positioning. Define the expression for the association between part dimensions. Use the unit assembled in the assembly environment as the assembly node. Store the assembly relationship between parts. According to the assembly relationship, the child component of the assembly relationship is corresponding to the assembly relationship. The assembly node is referenced in a tree structure according to the positioning relationship between the assembly nodes. Maintain the positioning relationship between the assembly nodes. Implement standardized part assembly according to the positioning relationship between the assembly nodes.

[0016] Compared with the prior art, the beneficial effects of this disclosure are as follows:

[0017] This disclosure integrates industry standards into the assembly module by supporting data configuration and assembly according to industry standards, thereby facilitating the assembly of standardized parts, effectively improving assembly efficiency, and further enhancing control over the design schedule. Attached Figure Description

[0018] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0019] Figure 1 This is a schematic diagram of the assembly method framework according to an embodiment of the present disclosure. Detailed implementation method:

[0020] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] Example 1

[0024] One embodiment of this disclosure provides a CAD part assembly method, including:

[0025] Define the data model and abstract model of PDM basic data;

[0026] Define various assembly rules for a part, and obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the part, as well as the upper-level assembly parts that can be assembled.

[0027] Obtain the parent-child relationship between parts in assembly and the parent-child relationship between parts in positioning. Define the expression for the association between part dimensions. Use the unit assembled in the assembly environment as the assembly node. Store the assembly relationship between parts. According to the assembly relationship, the child component of the assembly relationship is corresponding to the assembly relationship. The assembly node is referenced in a tree structure according to the positioning relationship between the assembly nodes. Maintain the positioning relationship between the assembly nodes. Implement standardized part assembly according to the positioning relationship between the assembly nodes.

[0028] As one embodiment, among the various rules for defining parts, assembly rules include: size rules, storage rules, part type definitions, attribute configurations, seed configurations, and positioning rules.

[0029] Specifically, this disclosure designs an assembly module, which includes the following sub-modules: a PDM basic data module, a model assembly framework, an interface with 3D software, and a server.

[0030] The PDM basic data module supports configuring assembly parts and related data according to industry standards. It is responsible for managing the basic data required by the module and supports configuring and importing parts that conform to industry standards, part-related dimensions, standard constraint dimension associations, part assembly rules, and part positioning rules into the server according to the configuration rules.

[0031] The basic model module defines the data model and abstraction required by the PDM basic data module, including: part assembly rules, part size rules, part type, part attributes, seeds, and part positioning rules.

[0032] The assembly rules for a part define the rules for assembling this part with other components. The assembly rules specify the theoretically permissible lower-level sub-assemblies and higher-level assemblies that can be assembled onto this part. Assembly rules allow designers to set or modify the assembly relationships between parts according to industry rules.

[0033] The dimensional rules for parts define configurations that conform to industry standards. Designers need to configure certain dimensions as critical dimensions according to industry standards. Critical dimensions are used to filter the required dimensional data from the industry standard dimensions and adjust the overall dimensions of the part model according to the industry standards. For non-standard parts, a range of dimensional data is allowed.

[0034] The part type defines the part's configuration. Designers can configure the part's full specification name under industry standards and the degree of standardization of the part itself.

[0035] The part attribute definition includes attributes other than dimensions and name, such as material, center of gravity, mass, standards followed, and remarks. Designers can configure part attributes according to industry standards.

[0036] The seed configuration defines the configuration of the 3D model, standard dimension tables, and other necessary model files associated with the part. It allows designers to configure file information related to the part.

[0037] Positioning rules define industry-standard positioning methods between parts. This allows designers to define the positioning methods required for their designs while still meeting industry standards.

[0038] The basic service module defines the management corresponding to the basic model, mainly providing services for adding, deleting, modifying and querying the corresponding model, data hierarchical connection and interface information binding, including: assembly rule service, seed configuration service, part type service, part attribute service and positioning rule service.

[0039] The model assembly framework allows designers to assemble parts based on industry standards using basic model information configured according to industry standards, including: assembly engine and assembly service.

[0040] The assembly engine defines assembly-related models, including: features, assembly nodes, assembly node positioning sequences, dimensions, assembly environment, node diagrams, parts, and part attributes.

[0041] Features are defined as features belonging to assembly nodes or parts that are related to component assembly. They are identified globally by feature IDs and include: assembly relationships, positioning relationships, expressions, and expression nodes.

[0042] Assembly relationships define the parent-child relationships between components, primarily recording the parent and child components in an assembly. Assembly relationships also record the theoretically subordinate relationships within a component assembly.

[0043] Positioning relationships define the parent-child relationships between components, primarily recording the parent and child components in a component's positioning. Positioning relationships also record the actual subordinate relationships in a component's positioning.

[0044] Expressions define the relationships between component dimensions. Designers use expressions to establish these relationships between different component dimensions, implementing dimensional relationships between components according to standards. Expressions focus on the calculation of data between component dimensions.

[0045] An expression node contains the expression, the assembly nodes to which the expression belongs, and records other expression nodes affected by the expression and the expressions that affect this expression node, maintaining data consistency between expressions.

[0046] The expressions include: the dimensions of other parts are described as a path from the common parent node of the assembly to the specific dimensions of a certain part, the dimensions of this part, addition, subtraction, multiplication, and division operators between dimensions, and constants. Attributes of child assemblies or parent assemblies (with a common parent) called by this assembly are separated by ".", and attributes of cross-level (parts without a common parent node except the top-level assembly) associations are separated by "@" (the dimensions of the final part are separated by ".").

[0047] The dimensions define the dimensions of parts in the assembly environment. Unlike the dimensions in the base data, the dimensions in this module do not focus on configuration-related data, but only on dimensional data.

[0048] The attribute definition is the attribute of a part in the assembly environment. Unlike the attributes of the basic data, the attributes in this module do not focus on configuration-related data, but only on the attribute content.

[0049] Parts define components within the assembly environment. The part model includes part type, part size, and part attributes from the basic data management module. It also includes features used to record assembly attributes between parts, such as positioning relationships and expression nodes. Parts serve as the corresponding carriers of 3D model data information for the assembly environment.

[0050] An assembly node serves as the unit of assembly within an assembly environment. It stores the assembly relationships between parts, identifies the child components within those relationships, and maintains the parent-child relationships between parts according to the assembly relationships. The root assembly node stores empty assembly relationships and child components.

[0051] The assembly node positioning sequence references assembly nodes in a tree structure based on the positioning relationships between assembly nodes, thus maintaining the positioning relationships between assembly nodes.

[0052] An assembly environment is the carrier of project data for designers performing assembly design. It records global data and operations during the design process, including the root assembly node, the root node of the assembly node positioning sequence, all parts added to the project, and the undo / redo stack. Each assembly design project uniquely corresponds to one assembly environment.

[0053] The assembly service supports complex operations on the assembly model, including: assembly environment server, expression node server, part manager, undo / undo stack manager, update manager, etc. The assembly environment server handles operations such as loading, copying, modifying, and storing the assembly environment.

[0054] The expression node server handles operations on expression nodes, including initializing all expression nodes, retrieving all expression nodes related to a specific assembly node, and updating expression nodes.

[0055] The Parts Manager stores and manages all parts in the work environment, supporting operations such as assigning unique codes to parts and adding, deleting, modifying, and querying parts.

[0056] The undo / redo stack manager manages the undo / redo stack within the framework. Compared to the system-wide undo / redo stack, this module's undo / redo stack defines undo transactions in greater detail, allowing designers to perform more precise assembly and data modifications. Assembly transactions are encapsulated within each functional and data unit of this module. The manager is responsible for retrieving and executing the undo / redo instructions from the specific working units of the undo / redo stack nodes.

[0057] The update manager is responsible for updating system data and structure after other functional modules have performed their operations.

[0058] The interface display and assembly design operation function set corresponding to the interface definition module of the 3D software, as well as the requirements of industry standards, include: interface information, commands, and interfaces for operating the 3D software.

[0059] The interface information defines the interface that needs to be displayed visually in this module. There are corresponding sets of interface display interfaces for both the PDM basic data submodule and the assembly framework submodule.

[0060] The command defines the basic functions required by industry standards for designers to perform assembly design, including: array, assembly cutting, part insertion, part editing, part replacement, and part deletion.

[0061] The interface for operating 3D software defines the interfaces for mutual calls with other data modules of CAD software, including interfaces for calling 3D model rendering and interfaces for reading file data.

[0062] The server is used to store PDM basic data module configuration information, assembly file information, industry standard information, etc.

[0063] As one embodiment, the implementation method specifically includes:

[0064] 1. Use CAD software to create basic part seed files by drawing sketches, extruding, and performing Boolean operations. During the drawing process, set the part dimensions according to industry standards.

[0065] 2. Configure the part type, attributes, assembly rules, positioning rules, storage rules, and seed file in the PDM system according to industry rules.

[0066] 3. In the assembly module, create a new assembly environment, start the parts manager, and select the sub-parts and assemblies that have been configured in the PDM file according to industry rules and assembly rules.

[0067] 4. In accordance with industry standards and positioning rules, the sub-parts are associated and bound in position. The shape and dimensions of the parts are bound and associated with their positioning dimensions using expressions. The update manager updates the relevant data between the parts during the assembly process.

[0068] 5. After assembly is completed, an assembly tree data structure consisting of assembly nodes and an assembly node positioning sequence will be generated in the assembly environment to describe the assembly and positioning relationships between parts.

[0069] 6. During the assembly process, the assembly operation can be adjusted using the undo / redo function.

[0070] Example 2

[0071] One embodiment of this disclosure provides a CAD part assembly system, including:

[0072] The basic model module is used to define the data model and abstract model of the PDM basic data;

[0073] The server is used to define various assembly rules for parts, and to obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the parts, as well as the upper-level assembly parts that can be assembled.

[0074] Obtain the parent-child relationship between parts in assembly and the parent-child relationship between parts in positioning. Define the expression for the association between part dimensions. Use the unit assembled in the assembly environment as the assembly node. Store the assembly relationship between parts. According to the assembly relationship, the child component of the assembly relationship is corresponding to the assembly relationship. The assembly node is referenced in a tree structure according to the positioning relationship between the assembly nodes. Maintain the positioning relationship between the assembly nodes. Implement standardized part assembly according to the positioning relationship between the assembly nodes.

[0075] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. 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, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0076] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus 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.

[0077] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A CAD part assembly method, characterized in that, include: Define the data model and abstract model of PDM basic data; Define various assembly rules for a part, and obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the part, as well as the upper-level assembly parts that can be assembled. Among the various assembly rules for defining parts, the assembly rules include: size rules, storage rules, part type definitions, attribute configurations, seed configurations, and positioning rules; wherein, positioning rules define the positioning method between parts, and the assembly engine defines the assembly-related model, including features, assembly nodes, assembly node positioning sequences, dimensions, assembly environment, node diagrams, parts, and part attributes. The system obtains the parent-child relationships between assembled parts and the parent-child relationships between their positioning parts, defines expressions for the association between part dimensions, and allows designers to associate different part dimensions through these expressions, thus implementing the dimensional association between parts according to standards. Units assembled in the assembly environment are used as assembly nodes to store the assembly relationships between parts. Sub-components of the assembly relationships are identified based on the corresponding assembly relationships. Assembly nodes are referenced in a tree structure based on the positioning relationships between them, maintaining the positioning relationships between assembly nodes. Standardized part assembly is then achieved based on the positioning relationships between assembly nodes.

2. The CAD part assembly method as described in claim 1, characterized in that, The assembly rules define the rules for assembling parts with other parts. The assembly rules for parts specify the lower-level sub-assemblies that can be assembled onto the parts and the upper-level assemblies that the parts can be assembled with. The assembly rules support setting or modifying the assembly relationships between parts according to the rules.

3. The CAD part assembly method as described in claim 1, characterized in that, The part size rules define standard part size configurations. Based on the standards, some dimensions are configured as critical dimensions. The critical dimensions are used to filter the required size data from the standard dimensions and adjust the overall size of the part model according to the standards. For non-standard parts, the range of size data that can be configured is allowed.

4. The CAD part assembly method as described in claim 1, characterized in that, The part type defines the configuration of the part itself, and the part attributes define the part's properties other than its size and name, including material, center of gravity, mass, standards followed, and remarks.

5. A CAD part assembly method as described in claim 1, characterized in that, The seed configuration defines the configuration of the 3D model, standard dimension table and other model files associated with the part, and configures the file information related to the part.

6. The CAD part assembly method as described in claim 1, characterized in that, Features are defined as features belonging to assembly nodes or parts that are related to part assembly. They are identified globally by feature IDs, including assembly relationships, positioning relationships, expressions, and expression nodes.

7. A CAD part assembly method as described in claim 1, characterized in that, Assembly relationships define the parent-child relationships between parts, recording the parent and child parts of the assembly and the subordinate relationships of the assembly. Positioning relationships define the parent-child relationships between parts, recording the parent and child parts of the positioning.

8. A CAD parts assembly system, characterized in that, include: The basic model module is used to define the data model and abstract model of the PDM basic data; The server is used to define various assembly rules for parts, and to obtain the lower-level sub-assemblies that the assembly rules allow to be assembled onto the parts, as well as the upper-level assembly parts that can be assembled. Among the various assembly rules for defining parts, the assembly rules include: size rules, storage rules, part type definitions, attribute configurations, seed configurations, and positioning rules; wherein, positioning rules define the positioning method between parts, and the assembly engine defines the assembly-related model, including features, assembly nodes, assembly node positioning sequences, dimensions, assembly environment, node diagrams, parts, and part attributes. The system obtains the parent-child relationships between assembled parts and the parent-child relationships between their positioning parts, defines expressions for the association between part dimensions, and allows designers to associate different part dimensions through these expressions, thus implementing the dimensional association between parts according to standards. Units assembled in the assembly environment are used as assembly nodes to store the assembly relationships between parts. Sub-components of the assembly relationships are identified based on the corresponding assembly relationships. Assembly nodes are referenced in a tree structure based on the positioning relationships between them, maintaining the positioning relationships between assembly nodes. Standardized part assembly is then achieved based on the positioning relationships between assembly nodes.

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