Mechanical part-oriented parameterized three-dimensional modeling and engineering drawing automatic generation method

Abstract

The invention relates to the technical field of mechanical design automation, in particular to a parameterized three-dimensional modeling and engineering drawing automatic generation method for mechanical parts, which comprises the following steps that: a user inputs design parameters of the mechanical parts through a visual interface, the design parameters comprise basic dimension parameters, characteristic geometric parameters and engineering constraint parameters, and the basic dimension parameters, the characteristic geometric parameters and the engineering constraint parameters are input into the visual interface; all the parameters and the mutual dependency relationship are stored in a configuration data structure; and constructing a parameter dynamic constraint network. According to the method, parameter self-consistent and compliance verification is guaranteed through a parameter dynamic constraint network, complex feature modeling is achieved through a coordinate system rotation matrix, automatic labeling is completed in combination with geometric topology analysis, intelligent view planning and a parameterized template, and the method depends on a three-layer architecture platform. One-button type closed-loop automation from parameter input to model generation, interference diagnosis and drawing output is achieved, and the design and manufacturing data transmission bottleneck is broken through.

Description

Technical Field

[0001] This invention relates to the field of mechanical design automation technology, specifically to a method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts. Background Technology

[0002] In modern manufacturing, mechanical design is a core part of the product development lifecycle. Traditional design processes heavily rely on manual operations by design engineers. Engineers first use CAD software (such as CATIA, SolidWorks, AutoCAD, etc.) to create a 3D solid model, and then manually create 2D engineering drawings based on the 3D model. This process typically includes selecting views (front view, top view, side view), creating sectional views and enlarged details, manually dimensioning, tolerances, geometric tolerances, surface roughness, and adding technical requirements.

[0003] However, in the design and manufacturing process of complex mechanical parts, traditional methods rely heavily on manual operations by designers in general CAD software, which has the following significant drawbacks:

[0004] The process is fragmented and inefficient: each design step needs to be completed manually, especially for complex features such as inclined oil holes and curved oil grooves, which require a lot of manual geometric calculations and working plane transformations, resulting in a long design cycle.

[0005] High risks to design accuracy and reliability: Manual parameter adjustments can easily lead to dimensional deviations and assembly interference. Existing CAD software interference checks are mostly handled by independent post-processing modules, which cannot be linked with design parameters in real time, resulting in weak error prevention capabilities.

[0006] Lack of knowledge-driven compliance verification: Traditional design methods fail to deeply integrate with engineering design knowledge bases, making it impossible to automatically perform compliance checks on material properties, process constraints, and tolerances, and design risks are difficult to detect in a timely manner. Summary of the Invention

[0007] The purpose of this invention is to provide a method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts, so as to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts, comprising the following steps:

[0009] S1: Parameter Input and Preprocessing: The user inputs the design parameters of the mechanical part through a visual interface. The design parameters include basic dimensional parameters. Characteristic geometric parameters and engineering constraint parameters All parameters and their dependencies are stored in the configuration data structure;

[0010] S2: Programmatic 3D Modeling Based on Dynamically Constrained Parametric Networks: A Dynamically Constrained Parametric Network (DCN) is constructed. The mathematical relationships and logical constraints between parameters are clarified through the constraint matrix. The network iterative solution is triggered when parameters are updated to ensure parameter self-consistency. The operation of the DCN includes knowledge-based compliance verification to ensure the consistency of parameters with engineering specifications during the modeling process. Combined with dynamic transformation technology of the working plane, complex geometric features are generated programmatically to obtain a high-precision 3D model.

[0011] S3: Real-time compliance verification and interference diagnosis of 3D models: Calls constraint functions in the engineering design knowledge base to perform real-time verification of material properties, process constraints, tolerances and fits and assembly interference of 3D models, and provides feedback on verification results and design risk warnings;

[0012] S4: Intelligent Engineering Drawing Automatic Generation: Performs geometric topology analysis on the 3D model, determines the main view, sectional view and auxiliary view through intelligent view planning algorithm; realizes automatic annotation of dimensions, tolerances, surface roughness and special marks based on parametric template mapping technology, and outputs 2D engineering drawings;

[0013] S5: Full-process automated integration: The above steps are automated in a "one-click" closed loop through a three-layer architecture platform. The three-layer architecture includes a visual interaction layer, a programmatic modeling layer, and an engineering drawing generation layer, and collaborative work is achieved through standardized API interfaces.

[0014] Preferably, the classification definition of the parameters in step S1 is as follows:

[0015] Basic Dimensions The core dimensional parameters that characterize the overall outline of a mechanical part, including the outer diameter, inner diameter, width, length, and height, are the parameters that determine the basic shape of the part.

[0016] Characteristic geometric parameters Geometric parameters characterizing the local functional features of a part, including the diameter, depth, and angle of holes; the width, depth, and curvature of oil grooves; and the dimensions and positional parameters of bosses.

[0017] Engineering constraint parameters : Constraint parameters characterizing the compliance requirements of part design, including minimum wall thickness, stress safety factor, fit clearance and allowable material stress based on engineering specifications or experience.

[0018] Preferably, the construction and computation of the Dynamically Constrained Network (DCN) in step S2 includes:

[0019] Define the parameter constraint matrix ,in Indicates parameters For parameters The influence weights or functional dependencies;

[0020] When modifying input parameters At that time, through the function Solving for correlation parameters Allowed input range ;

[0021] Knowledge-based compliance verification: After each parameter update and iterative solution, the system calls the constraint functions in the engineering design knowledge base. Compliance verification is performed on the key characteristics of the parts corresponding to the parameters; taking the part thickness constraint as an example, the part thickness... It must meet the requirements of the engineering design knowledge base based on inner diameter. Constraints If the verification fails, the system will output a risk warning in real time on the visual interface.

[0022] Preferably, the dynamic transformation technology of the working plane in step S2 is used to generate complex geometric features such as inclined oil holes and curved oil grooves. The specific steps are as follows:

[0023] Define the initial working plane (WCS) to determine the starting position of complex features. ;

[0024] Based on characteristic parameters (angle of the inclined hole) ,direction Rotation angle Calculate the 3D rotation matrix ,in These are rotation matrices about the X, Y, and Z axes, respectively;

[0025] By transforming the formula , initial geometric primitives Transform the working plane to the target angle to obtain the transformed geometric primitives. ;

[0026] The transformed geometric primitives Perform procedural geometric operations such as extrusion and Boolean cutting on the plane to generate complex features. .

[0027] Preferably, the object of geometric topology analysis in step S4 is a three-dimensional model conforming to the STEP standard. The analysis content includes: the boundary representation (B-rep) of the model, the feature history, the normal vectors of each surface, the direction vectors and length information of the key lines. Through analysis, the main features of the part, mating surfaces, holes and oil grooves are accurately identified.

[0028] Preferably, the intelligent view planning algorithm in step S4 specifically includes:

[0029] Main view planning: Traverse the six orthogonal projection directions ±X, ±Y, and ±Z, calculate the amount of visible feature information on the projection surface in each direction. The amount of visible feature information is quantitatively evaluated by the length of the projection outline, the number of visible holes, and the feature complexity. Select the direction with the largest amount of information as the projection direction of the main view.

[0030] Sectional view planning: Detect whether the internal structure of the 3D model is occluded by the outer contour. If occlusion exists, automatically plan the best cutting plane based on the assembly axis or symmetry plane of the part to generate a full sectional view or a half sectional view.

[0031] Auxiliary view planning: Based on manufacturing process requirements and the geometric complexity of local features, automatically generate enlarged local views or auxiliary views to clearly express key feature details.

[0032] Preferably, the parameterized template mapping and automated annotation in step S4 specifically include:

[0033] Build parameterized templates ,in This refers to the types of geometric features identified in the 3D model (including holes, shoulders, high-precision mating surfaces, etc.). This is the set of drafting standards corresponding to the geometric features;

[0034] Automated dimensioning: Identifies key contour lines and center lines in the view, and automatically adds basic dimensions, datum dimensions, and coordinate dimensions according to part type and drafting specifications;

[0035] Automated tolerance annotation: For identified critical mating surfaces, based on their mating characteristics (transition fit, clearance fit, etc.), it uses a parametric template... The system automatically matches the corresponding dimensional tolerance grade and symbol and completes the annotation.

[0036] Automated marking of special marks: Combining the constraints of part material, heat treatment process and design requirements, the system automatically matches and marks surface roughness symbols, and performs special marking on key areas of high-precision mating surfaces.

[0037] Preferably, in step S5, each layer of the architecture achieves data interaction and logical collaboration through standardized API interfaces. The specific collaboration process is as follows:

[0038] Parameter transmission and verification collaboration: After receiving the design parameters input by the user, the visualization interaction layer transmits them to the procedural modeling layer in real time; the modeling layer completes the parameter compliance verification through the parameter dynamic constraint network and engineering design knowledge base, and feeds back the verification results (including parameter range prompts and error messages) to the visualization interaction layer for visualization display;

[0039] Modeling and Diagnosis Collaboration: After the parameters are verified, the user triggers the "Generate 3D Model" command. The procedural modeling layer executes the procedural modeling process and performs assembly interference checks in real time. The dynamic rendering data of the 3D model and the interference diagnosis report are sent back to the visualization interaction layer for the user to view.

[0040] Collaborative drawing generation and output: After the user triggers the "Generate 2D Drawing" command, the procedural modeling layer outputs the STEP format 3D model to the engineering drawing generation layer; the engineering drawing generation layer generates engineering drawings through geometric topology analysis, intelligent view planning and automated annotation algorithms, and feeds back the DXF / EXB format drawing files to the visualization interaction layer to complete the output prompts.

[0041] Compared with the prior art, the beneficial effects of the present invention are:

[0042] This invention ensures parameter self-consistency and real-time compliance verification by constructing a dynamic constraint network, efficiently generates complex features using dynamic transformation technology of the working plane based on coordinate system rotation matrix, and achieves automated annotation of engineering drawings by using geometric topology analysis, intelligent view planning, and parametric template mapping. Furthermore, it deeply integrates the visualization interaction layer, the procedural modeling layer, and the engineering drawing generation layer through standardized API interfaces to build a three-layer architecture platform. Ultimately, it realizes "one-click" closed-loop automated design from parameter input to 3D model generation, assembly interference diagnosis, and 2D engineering drawing output, effectively improving design standardization and efficiency, and eliminating data transmission bottlenecks between design and manufacturing. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall process of the parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Please see Figure 1 This invention provides a technical solution: a method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts, comprising the following steps:

[0046] S1: Parameter Input and Preprocessing: The design parameters of mechanical parts are divided into basic dimension parameters. Characteristic geometric parameters and engineering constraint parameters Users input design parameters for mechanical parts through a visual interface. All parameters and their dependencies are stored in a configuration data structure (bearing_config.json file), where the specific definitions of each parameter are as follows:

[0047] Basic Dimensions The core dimensional parameters that characterize the overall outline of a mechanical part, including the outer diameter, inner diameter, width, length, and height, are the parameters that determine the basic shape of the part.

[0048] Characteristic geometric parameters Geometric parameters characterizing the local functional features of a part, including the diameter, depth, and angle of holes; the width, depth, and curvature of oil grooves; and the dimensions and positional parameters of bosses.

[0049] Engineering constraint parameters : Constraint parameters characterizing the compliance requirements of part design, including minimum wall thickness, stress safety factor, fit clearance and allowable material stress based on engineering specifications or experience;

[0050] S2: Procedural 3D Modeling Based on Parametric Dynamic Constraint Networks: Constructing a Parametric Dynamic Constraint Network (DCN) by defining the parametric constraint matrix. The mathematical relationships and logical constraints between parameters are clearly defined. Network iteration is triggered during parameter updates to ensure parameter self-consistency. Furthermore, the computation of the dynamic constraint network includes knowledge-based compliance checks to ensure consistency between parameters and engineering specifications during modeling. Combined with dynamic transformation technology of the working plane, complex geometric features are procedurally generated to obtain a high-precision 3D model. The construction and computation of the dynamic constraint network (DCN) include:

[0051] Define the parameter constraint matrix ,in Indicates parameters For parameters The influence weights or functional dependencies;

[0052] When modifying input parameters At that time, through the function Solving for correlation parameters Allowed input range ;

[0053] Knowledge-based compliance verification: After each parameter update and iterative solution, the system calls the constraint functions in the engineering design knowledge base. (For example, minimum wall thickness, stress safety factor, etc.), perform compliance verification on the key characteristics of the parts corresponding to the parameters; taking part thickness constraints as an example, part thickness It must meet the requirements of the engineering design knowledge base based on inner diameter. Constraints If the verification fails, the system will output a risk warning in real time on the visual interface;

[0054] To efficiently and accurately construct complex geometric features such as inclined oil holes and curved oil grooves, this invention employs the aforementioned dynamic transformation technology of the working plane to generate these complex geometric features. The specific steps are as follows:

[0055] Define the initial working plane (WCS) to determine the starting position of complex features. ;

[0056] Based on characteristic parameters (angle of the inclined hole) ,direction Rotation angle ) Calculate the 3D rotation matrix required to move from the global coordinate system to the feature local coordinate system. ,in These are rotation matrices about the X, Y, and Z axes, respectively;

[0057] By transforming the formula , initial geometric primitives By rotation matrix Transform the working plane to the target angle to obtain the transformed geometric primitives. ;

[0058] geometric primitives after transformation Perform procedural geometric operations such as extrusion and Boolean cutting on the plane to generate complex features. ;

[0059] This step avoids the cumbersome auxiliary plane construction steps in traditional CAD software, significantly improving the modeling efficiency and accuracy of complex parts. At the same time, it solves the problems of low efficiency and error-prone conversion between 3D models and 2D drawings by deeply analyzing the geometric topology of 3D models and combining parametric template mapping to achieve fully automated and high-standard generation of engineering drawings, effectively solving the data transfer bottleneck between design and manufacturing.

[0060] S3: Real-time compliance verification and interference diagnosis of 3D models: Calls constraint functions in the engineering design knowledge base to perform real-time verification of material properties, process constraints, tolerances and fits and assembly interference of 3D models, and provides feedback on verification results and design risk warnings;

[0061] S4: Intelligent Engineering Drawing Automatic Generation: Performs geometric topology analysis on the 3D model, determines the main view, sectional view, and auxiliary views through intelligent view planning algorithms; based on parametric template mapping technology, it realizes automated annotation of dimensions, tolerances, surface roughness, and special marks. After completing all view planning and automated annotation, the system integrates the drawing data and outputs engineering drawings in DXF / EXB format that conform to manufacturing specifications. The object of geometric topology analysis is a 3D model that conforms to the STEP standard. The analysis content includes: the boundary representation (B-rep) of the model, feature history, normal vectors of each surface, direction vectors and length information of key lines. Through analysis, the main features of the parts, mating surfaces, holes, and key structures of oil grooves are accurately identified.

[0062] The aforementioned intelligent view planning algorithm specifically includes:

[0063] Main view planning: Traverse the six orthogonal projection directions ±X, ±Y, and ±Z, calculate the amount of visible feature information on the projection surface in each direction. The amount of visible feature information is quantified and evaluated by the length of the projection outline, the number of visible holes, and the feature complexity. Select the direction with the largest amount of information as the projection direction of the main view.

[0064] Sectional view planning: For complex parts (such as tilting pad bearings), the algorithm detects whether the internal structure (such as oil holes and oil grooves) is obscured by the outer contour. If it is obscured, the algorithm automatically plans the optimal cutting plane based on the assembly axis or symmetry plane of the part, generating a full sectional view or a half sectional view to ensure the clarity and completeness of the drawing;

[0065] Auxiliary view planning: Based on manufacturing process requirements and the geometric complexity of local features, automatically generate enlarged local views or auxiliary views to clearly express key feature details;

[0066] The aforementioned parametric template mapping and automated annotation specifically include:

[0067] Build parameterized templates ,in This refers to the types of geometric features identified in the 3D model (including holes, shoulders, high-precision mating surfaces, etc.). The template is a set of drafting standards corresponding to geometric features, and it supports customized adjustments by enterprises.

[0068] Automated dimensioning: Identifies key contour lines and center lines in the view, and automatically adds basic dimensions, datum dimensions, and coordinate dimensions according to part type and drafting specifications;

[0069] Automated tolerance annotation: For identified critical mating surfaces, based on their mating characteristics (transition fit, clearance fit, etc.), it uses a parametric template... The system automatically matches the corresponding dimensional tolerance grade and symbol and completes the annotation.

[0070] Automated marking of special marks: Combining the constraints of part material, heat treatment process and design requirements, the surface roughness symbols are automatically matched and marked, and special markings are made for key areas of high-precision mating surfaces;

[0071] S5: Full-Process Automated Integration: A three-tier architecture platform enables "one-click" closed-loop automation of the above steps. This involves deep integration and logical restructuring of the previously separate parametric modeling tools (CADQuery), drawing tools (FreeCAD), and visualization interface framework (QT). Each layer achieves data interaction and logical collaboration through standardized API interfaces. Specifically, the procedural modeling layer is configured with a dynamic constraint network and a dynamic work plane transformation module; the drawing generation layer is configured with a geometric topology analysis module, an intelligent view planning module, and a parametric template mapping module. This constructs a knowledge-driven three-tier automated design platform, achieving "one-click" full-process automation from parameter input to model / drawing output, thereby improving the efficiency of drawing generation. The visualization interaction layer, procedural modeling layer, and drawing generation layer collaborate through standardized API interfaces. The specific collaborative process is as follows:

[0072] Parameter transmission and verification collaboration: After receiving the design parameters input by the user, the visualization interaction layer transmits them to the procedural modeling layer in real time; the modeling layer completes the parameter compliance verification through the parameter dynamic constraint network and engineering design knowledge base, and feeds back the verification results (including parameter range prompts and error messages) to the visualization interaction layer for visualization display;

[0073] Modeling and Diagnosis Collaboration: After the parameters are verified, the user triggers the "Generate 3D Model" command. The procedural modeling layer executes the procedural modeling process and performs assembly interference checks in real time. The dynamic rendering data of the 3D model and the interference diagnosis report are sent back to the visualization interaction layer for the user to view.

[0074] Collaborative drawing generation and output: After the user triggers the "Generate 2D Drawing" command, the procedural modeling layer outputs the STEP format 3D model to the engineering drawing generation layer; the engineering drawing generation layer generates engineering drawings through geometric topology analysis, intelligent view planning and automated annotation algorithms, and feeds back the DXF / EXB format drawing files to the visualization interaction layer to complete the output prompts.

[0075] This invention integrates the originally separate design processes into a "one-click" closed-loop process through the deep integration of a three-layer architecture (visual interaction layer, procedural modeling layer, and engineering drawing generation layer) and standardized API collaboration. By combining parametric driving, procedural modeling, and dynamic transformation of the work plane, it eliminates the manual auxiliary operation of complex feature modeling in traditional CAD software, realizes efficient connection from parameter input to model generation, significantly shortens the design cycle, and completely breaks the efficiency bottleneck caused by process fragmentation.

[0076] By constructing mathematical relationships and logical constraints between parameters through a dynamic constraint network, the system automatically iterates and solves the problem when parameters are modified, ensuring parameter self-consistency and reducing dimensional deviations. An innovative dynamic transformation technology for the working plane enables precise, programmed generation of complex features, reducing manual operation errors. Simultaneously, interference checking and modeling processes are linked in real time, allowing for interference diagnosis during the design phase. Problems are detected and reported immediately, effectively mitigating assembly risks and improving design reliability. This invention deeply integrates an engineering design knowledge base with the dynamic constraint network. After each parameter update, the system automatically calls constraint functions from the knowledge base for compliance verification. If designs do not conform to engineering specifications, risks are immediately alerted through a visual interface, enabling proactive prevention of design risks, reducing design defects, and improving design standardization and scientific rigor.

[0077] This invention analyzes the geometric and topological features of a 3D model in depth, automatically determines the optimal view form by combining an intelligent view planning algorithm, and then uses parametric template mapping technology to achieve standardized automatic annotation of dimensions, tolerances, surface roughness, etc. It can complete the conversion from a 3D model to a 2D engineering drawing without manual intervention, avoid errors and efficiency losses in data transmission, and ensure smooth connection between design and manufacturing processes.

[0078] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0079] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts, characterized by: Includes the following steps: S1: Parameter Input and Preprocessing: The user inputs the design parameters of the mechanical part through a visual interface. The design parameters include basic dimensional parameters. Characteristic geometric parameters and engineering constraint parameters All parameters and their dependencies are stored in the configuration data structure; S2: Programmatic 3D Modeling Based on Dynamic Parametric Constraint Network: A dynamic parametric constraint network is constructed, and the mathematical relationships and logical restrictions between parameters are clarified through the constraint matrix. When parameters are updated, the network iterative solution is triggered to ensure parameter self-consistency. The operation of the dynamic parametric constraint network includes knowledge base-driven compliance verification to ensure the consistency of parameters with engineering specifications during the modeling process. Combined with dynamic transformation technology of the working plane, complex geometric features are generated programmatically to obtain a high-precision 3D model. S3: Real-time compliance verification and interference diagnosis of 3D models: Calls constraint functions in the engineering design knowledge base to perform real-time verification of material properties, process constraints, tolerances and fits and assembly interference of 3D models, and provides feedback on verification results and design risk warnings; S4: Intelligent Engineering Drawing Automatic Generation: Performs geometric topology analysis on the 3D model and determines the main view, sectional view and auxiliary view through intelligent view planning algorithm; Based on parametric template mapping technology, the system can automatically annotate dimensions, tolerances, surface roughness, and special markings, and output two-dimensional engineering drawings. S5: Full-process automated integration: The above steps are automated in a "one-click" closed loop through a three-layer architecture platform. The three-layer architecture includes a visual interaction layer, a procedural modeling layer, and an engineering drawing generation layer, and collaborative work is achieved through standardized API interfaces.

2. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 1, characterized in that: The specific classification definition of the parameters in step S1 is as follows: Basic Dimensions The core dimensional parameters that characterize the overall outline of a mechanical part, including the outer diameter, inner diameter, width, length, and height, are the parameters that determine the basic shape of the part. Characteristic geometric parameters Geometric parameters characterizing the local functional features of a part, including the diameter, depth, and angle of holes; the width, depth, and curvature of oil grooves; and the dimensions and positional parameters of bosses. Engineering constraint parameters : Constraint parameters characterizing the compliance requirements of part design, including minimum wall thickness, stress safety factor, fit clearance and allowable material stress based on engineering specifications or experience.

3. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 2, characterized in that: The construction and computation of the parameter dynamic constraint network in step S2 includes: Define the parameter constraint matrix ,in Indicates parameters For parameters The influence weights or functional dependencies; When modifying input parameters At that time, through the function Solving for correlation parameters Allowed input range ; Knowledge-based compliance verification: After each parameter update and iterative solution, the system calls the constraint functions in the engineering design knowledge base. Compliance verification is performed on the key characteristics of the parts corresponding to the parameters; taking the part thickness constraint as an example, the part thickness... It must meet the requirements of the engineering design knowledge base based on inner diameter. Constraints If the verification fails, the system will output a risk warning in real time on the visual interface.

4. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 3, characterized in that: The dynamic transformation technology of the working plane in step S2 is used to generate complex geometric features such as inclined oil holes and curved oil grooves. The specific steps are as follows: Define the initial working plane (WCS) to determine the starting position of complex features. ; Calculate the 3D rotation matrix based on the characteristic parameters. ,in These are rotation matrices about the X, Y, and Z axes, respectively; By transforming the formula , initial geometric primitives Transform the working plane to the target angle to obtain the transformed geometric primitives. ; The transformed geometric primitives Perform procedural geometric operations such as extrusion and Boolean cutting on the plane to generate complex features. .

5. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 4, characterized in that: In step S4, the object of geometric topology analysis is a three-dimensional model that conforms to the STEP standard. The analysis content includes: boundary representation of the model, feature history, surface normal vectors, direction vectors and length information of key lines. Through analysis, the main features of the part, mating surfaces, holes and oil grooves are accurately identified.

6. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 5, characterized in that: The intelligent view planning algorithm in step S4 specifically includes: Main view planning: Traverse the six orthogonal projection directions ±X, ±Y, and ±Z, calculate the amount of visible feature information on the projection surface in each direction. The amount of visible feature information is quantitatively evaluated by the length of the projection outline, the number of visible holes, and the feature complexity. Select the direction with the largest amount of information as the projection direction of the main view. Sectional view planning: Detect whether the internal structure of the 3D model is occluded by the outer contour. If occlusion exists, automatically plan the best cutting plane based on the assembly axis or symmetry plane of the part to generate a full sectional view or a half sectional view. Auxiliary view planning: Based on manufacturing process requirements and the geometric complexity of local features, automatically generate enlarged local views or auxiliary views to clearly express key feature details.

7. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 6, characterized in that: The parametric template mapping and automated annotation in step S4 specifically include: Build parameterized templates ,in The geometric feature types identified in the 3D model. This is the set of drafting standards corresponding to the geometric features; Automated dimensioning: Identifies key contour lines and center lines in the view, and automatically adds basic dimensions, datum dimensions, and coordinate dimensions according to part type and drafting specifications; Automated tolerance annotation: For identified critical mating surfaces, based on their mating properties, it uses a parametric template... The system automatically matches the corresponding dimensional tolerance grade and symbol and completes the annotation. Automated marking of special marks: Combining the constraints of part material, heat treatment process and design requirements, the system automatically matches and marks surface roughness symbols, and performs special marking on key areas of high-precision mating surfaces.

8. The method for parametric 3D modeling and automatic generation of engineering drawings for mechanical parts according to claim 7, characterized in that: In step S5, each layer of the architecture achieves data interaction and logical collaboration through standardized API interfaces. The specific collaboration process is as follows: Parameter transmission and verification collaboration: After receiving the design parameters input by the user, the visualization interaction layer transmits them to the procedural modeling layer in real time; the modeling layer completes the parameter compliance verification through the parameter dynamic constraint network and engineering design knowledge base, and feeds back the verification results (including parameter range prompts and error messages) to the visualization interaction layer for visualization display; Modeling and Diagnosis Collaboration: After the parameters are verified, the user triggers the "Generate 3D Model" command. The procedural modeling layer executes the procedural modeling process and performs assembly interference checks in real time. The dynamic rendering data of the 3D model and the interference diagnosis report are sent back to the visualization interaction layer for the user to view. Drawing generation and output collaboration: After the user triggers the "Generate 2D Drawing" command, the procedural modeling layer outputs the STEP format 3D model to the engineering drawing generation layer; the engineering drawing generation layer generates engineering drawings through geometric topology analysis, intelligent view planning and automated annotation algorithms, and feeds back the DXF / EXB format drawing files to the visualization interaction layer to complete the output prompts.

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