Three-dimensional model structure simplification method and system combined with topological optimization

Abstract

The invention provides a three-dimensional model structure simplification method and system combined with topological optimization, and relates to the technical field of three-dimensional model processing. First, initial three-dimensional model data generated by remote sensing photogrammetry and corresponding scene correlation features are obtained; wherein the initial three-dimensional model data covers model surface geometry, internal structure connection and material correlation information, and the scene correlation characteristics comprise terrain adaptation and structure bearing requirements, then constructing a topological optimization guide rule based on the data with the scene correlation characteristics, executing topological optimization operation and recording a structure adjustment track, and finally, constructing a topological optimization guide rule based on the data with the scene correlation characteristics. The method comprises the steps of obtaining a three-dimensional model middle frame and track information, then formulating a structure simplification strategy matched with a structure distribution rule and associated with key adjustment nodes, executing structure simplification operation and dynamic adaptation to obtain a simplified three-dimensional model structure and an adaptation record, and finally outputting structure data and the adaptation record of the simplified model. The problems of three-dimensional model structure simplification and scene adaptation can be effectively solved.

Description

Technical Field

[0001] This invention relates to the field of 3D model processing technology, and more specifically, to a method and system for simplifying 3D model structures by incorporating topology optimization. Background Technology

[0002] In the field of 3D model applications, with the continuous development of remote sensing photogrammetry technology, the acquired initial 3D model data is becoming increasingly rich and complex. This initial 3D model data includes surface geometry information, internal structural connection information, and material correlation information of various components, which can comprehensively reflect the characteristics of the target object. However, in practical applications, these complex 3D model data often have some problems.

[0003] On the one hand, in some application scenarios, such as mobile device display and rapid rendering, overly complex 3D models can lead to excessive consumption of computing resources and slow processing speed, affecting user experience and efficiency. On the other hand, most existing 3D model simplification methods do not fully consider the contextual characteristics of the scene in which the model exists. Scene-related characteristics, such as terrain adaptation requirements in remote sensing photogrammetry scenarios and structural load-bearing requirements of subsequent application scenarios, have a significant impact on the topology and simplification level of 3D models. Traditional methods often simplify 3D models only based on the model's own geometric features, ignoring the inherent connection between scene-related features and the 3D model's topology. This can result in simplified 3D models that may not meet the needs of actual application scenarios, leading to problems such as terrain incompatibility and insufficient structural load-bearing capacity. Summary of the Invention

[0004] In view of the aforementioned problems, and in conjunction with the first aspect of the present invention, embodiments of the present invention provide a method for simplifying the structure of a three-dimensional model by incorporating topology optimization, the method comprising:

[0005] Acquire the initial 3D model data and corresponding scene association features generated by remote sensing photogrammetry. The initial 3D model data includes the geometric information of the model surface, the connection information of the internal structure of the model, and the material association information of each component of the model. The scene association features include the terrain adaptation requirements under the remote sensing photogrammetry scene and the structural bearing requirements of the model in the subsequent application scene.

[0006] Topology optimization guidance rules are constructed based on initial 3D model data with scene association features. These rules are used to associate scene association features with the topology adjustment direction of the 3D model. The construction of these rules refers to the association between surface geometry information and internal structural connection information in the initial 3D model data.

[0007] Based on the topology optimization guidance rules, a topology optimization operation is performed on the initial three-dimensional model data. During the topology optimization operation, the adjustment trajectory of the internal structural connection relationship of the model is recorded synchronously to obtain the topology-optimized three-dimensional model intermediate frame and the corresponding structural adjustment trajectory information.

[0008] Based on the topology-optimized 3D model intermediate frame and the corresponding structural adjustment trajectory information, a structural simplification strategy is formulated. The structural simplification strategy matches the structural distribution pattern of the topology-optimized 3D model intermediate frame and associates the key structural adjustment nodes recorded in the structural adjustment trajectory information.

[0009] According to the structural simplification strategy, the structural simplification operation is performed on the intermediate frame of the topology-optimized 3D model. During the structural simplification operation, the simplification progress is synchronously fed back to the topology optimization guidance rules for dynamic adaptation, so as to obtain the simplified 3D model structure and the corresponding simplification adaptation record.

[0010] Output the structural data and simplified adaptation record corresponding to the simplified 3D model structure. The structural data corresponding to the simplified 3D model structure includes the surface geometry information, internal structural connection information and material association information of the simplified model.

[0011] Furthermore, embodiments of the present invention also provide a 3D model structure simplification system incorporating topology optimization, characterized in that it includes:

[0012] A processor; a machine-readable storage medium for storing machine-executable instructions of the processor; wherein the processor is configured to perform the above-described method for simplifying the three-dimensional model structure incorporating topology optimization by executing the machine-executable instructions.

[0013] In another aspect, embodiments of the present invention also provide a computer program product, the computer program product including machine-executable instructions stored in a computer-readable storage medium, a processor of a computer device reading the machine-executable instructions from the computer-readable storage medium, the processor executing the machine-executable instructions, causing the computer device to execute the above-described method for simplifying the three-dimensional model structure in conjunction with topology optimization.

[0014] Based on the above, by acquiring initial 3D model data containing rich information and corresponding scene-related features generated by remote sensing photogrammetry, topology optimization guidance rules are constructed based on the initial 3D model data with scene-related features. The scene-related features are associated with the topology adjustment direction of the 3D model, and the relationship between surface geometric information and internal structural connection information is referenced. This makes the topology optimization more in line with the needs of actual application scenarios. During the topology optimization operation, the adjustment trajectory of the internal structural connection relationship of the model is recorded simultaneously. The formulated structural simplification strategy matches the structural distribution law of the middle frame of the topology-optimized 3D model and associates key structural adjustment nodes, enabling targeted structural simplification and improving the efficiency and accuracy of simplification. During the structural simplification operation, the simplification progress is fed back to the topology optimization guidance rules for dynamic adaptation, realizing the organic interaction between optimization and simplification. This further improves the quality of the simplified 3D model structure. The final output of the simplified 3D model structure contains comprehensive information, effectively solving the problem of insufficient 3D model structure simplification and scene adaptation in the existing technology. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the execution flow of the three-dimensional model structure simplification method combined with topology optimization provided in an embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of exemplary hardware and software components of the 3D model structure simplification system combined with topology optimization provided in an embodiment of the present invention. Detailed Implementation

[0017] The present invention will now be described in detail with reference to the accompanying drawings. Figure 1 This is a flowchart illustrating a method for simplifying a 3D model structure by incorporating topology optimization, as provided in an embodiment of the present invention. The following is a detailed description of this method for simplifying a 3D model structure by incorporating topology optimization.

[0018] Step S110: Obtain the initial 3D model data and corresponding scene association features generated by remote sensing photogrammetry. The initial 3D model data includes the geometric information of the model surface, the connection information of the internal structure of the model, and the material association information of each component of the model. The scene association features include the terrain adaptation requirements under the remote sensing photogrammetry scene and the structural bearing requirements of the model's subsequent application scene.

[0019] In this embodiment, the optimization and simplification of a 3D model of a mountain communication base station is used as the application scenario throughout the text. Data is collected on a mountain communication base station area using UAV remote sensing photogrammetry technology. The initial 3D model data obtained covers complete 3D information of the main building of the base station, antenna support, equipment room, and other structures.

[0020] The model's surface geometry information includes the external contour data of the base station's main building, such as the 3D coordinate point set of the walls, the slope and edge curve parameters of the roof, the diameter and bending shape data of the antenna support poles, and the position and size parameters of the doors and windows in the equipment room. The model's internal structural connection information includes the connection node types (such as rigid and hinged) between the reinforced concrete load-bearing columns and beams in the main building, the distribution density and welding method of the reinforcing bars at the nodes, the flange connection dimensions and bolt distribution of the antenna support and the top of the main building, and the fixing positions of the expansion bolts between the equipment mounting racks inside the equipment room and the ground. The material association information records the material type and distribution of each structural component, such as the C30 concrete used in the walls of the main building, the HRB400 grade steel bars in the load-bearing columns, the 6061-T6 aluminum alloy of the antenna support, and the anti-static PVC board of the equipment room floor. The terrain adaptation requirements in the scene association features involve the spatial matching relationship between the base station model and the mountainous terrain, including the three-dimensional coordinate range of the contact area between the bottom of the base station and the mountain slope, the overlap requirement between the overall projected area of ​​the model in the terrain and the terrain contour lines, and the safe distance parameters between terrain obstacles (such as trees and rocks) around the base station and the model surface. The structural bearing requirements of the model's subsequent application scenarios include the total weight of the communication equipment that the base station needs to support (such as the weight distribution of macro base station equipment, battery packs, heat dissipation systems, etc.), the vibration frequency and amplitude range generated during equipment operation, the wind direction and wind pressure value of the maximum wind load that occurs once every 50 years in the local area, and the horizontal and vertical acceleration parameters corresponding to the earthquake intensity.

[0021] Step S120: Construct topology optimization guidance rules based on the initial 3D model data with scene association features. The topology optimization guidance rules are used to associate scene association features with the topology adjustment direction of the 3D model. The construction of the topology optimization guidance rules refers to the association relationship between surface geometric information and internal structural connection information in the initial 3D model data.

[0022] In mountainous communication base station scenarios, constructing topology optimization guidance rules requires transforming the aforementioned terrain adaptation and structural load-bearing requirements into quantifiable and executable 3D model topology adjustment criteria. The surface geometry information and internal structural connection information in the initial 3D model data are intrinsically related. For example, the surface geometry of the main building is determined by the layout of its internal load-bearing structure, and the surface morphology of the antenna support is related to the connection method of its internal supporting frame. The process of constructing topology optimization guidance rules involves analyzing these relationships to establish a mapping logic between scene-related features (terrain adaptation, structural load-bearing capacity) and model topology adjustment directions (such as structural additions / reductions, node reinforcement, and morphological deformation), ensuring that the adjusted model meets both terrain adaptation requirements and sufficient structural load-bearing capacity.

[0023] Step S121: Extract the scene association features from the initial 3D model data with scene association features, and separate the terrain association parameters corresponding to the terrain adaptation requirements and the load association parameters corresponding to the structural load requirements of the subsequent application scenarios of the model.

[0024] From the initial 3D model data with scene-related features, a feature separation algorithm is used to extract scene-related features. For terrain adaptation requirements, the separated terrain-related parameters include digital elevation model data of the base station area (containing 3D coordinate point clouds of the terrain), slope values ​​(slope magnitude and direction at each coordinate point), aspect distribution data (area percentage of different aspects), terrain roughness coefficient (statistical parameter reflecting the degree of surface undulation), and land cover type (such as the distribution range of soil, rock, and vegetation). For the structural load-bearing requirements of subsequent application scenarios, the separated load-bearing related parameters include the weight parameters of the communication equipment (self-weight of each device, center of gravity coordinates), the additional moment generated by the equipment installation location on the structure (calculated based on the relative position of the equipment's center of gravity and the installation node), wind load parameters (wind pressure shape coefficient and wind vibration coefficient at different heights), seismic action parameters (seismic influence coefficient, site category characteristic period), structural design service life, and structural importance coefficient.

[0025] Step S122: Analyze the adaptation relationship between the surface geometry information and terrain-related parameters in the initial three-dimensional model data, determine the geometric regions in the initial three-dimensional model data that need to be adjusted according to the terrain adaptation requirements, and mark them as terrain-sensitive regions.

[0026] A multi-dimensional adaptation analysis was performed on the surface geometry information of the initial 3D model data and the terrain-related parameters. First, the bottom surface geometry information of the base station model (such as the 3D coordinates of each bottom vertex) was overlaid and compared with the terrain digital elevation model data to calculate the gap value (elevation difference between each corresponding point) between the model bottom and the terrain surface. When the gap value of a certain area exceeds a set threshold (such as the gap range affecting model stability), that area is initially identified as a poorly adapted terrain area. Second, combined with terrain slope parameters, areas with large angles to the slope surface in the model surface geometry information were analyzed. For example, if the angle between the side of the base station main building and the steep mountain slope is too small, it may lead to insufficient lateral stability; such areas are also included in the candidate range. Furthermore, the impact of terrain roughness on the contact area of ​​the model foundation was considered. When the effective contact area between the bottom surface of the model and the rough terrain is lower than a set proportion, the corresponding area also needs to be adjusted. Based on the above analysis results, the edge area where the base station bottom contacts the terrain, the bottom connection area of ​​the antenna bracket in areas with large terrain undulations, and the outer wall area of ​​the equipment room near the slope are identified as geometric areas that need to be adjusted according to the terrain adaptation requirements. These areas are uniformly marked as terrain-sensitive areas. At the same time, the three-dimensional boundary coordinate range of each terrain-sensitive area and the corresponding terrain-related parameter feature values ​​are recorded.

[0027] Step S123: Analyze the matching relationship between the internal structural connection information and the load-bearing related parameters in the initial three-dimensional model data, determine the structural connection nodes in the initial three-dimensional model data that need to be strengthened according to the structural load-bearing requirements, and mark them as key load-bearing nodes.

[0028] Based on the internal structural connection information and load-bearing parameters of the initial 3D model data, a matching analysis of structural load-bearing capacity is performed. First, based on the equipment weight distribution and installation location in the load-bearing parameters, the loads (such as axial force, shear force, and bending moment) borne by each internal structural connection node are calculated. For example, for the connection node of the antenna support on the main building roof, the combined bending moment and shear force of the node need to be calculated based on the weight of the antenna and equipment and the horizontal force generated by wind load; for the connection node between the equipment mounting rack and the ground in the equipment room, its vertical pressure and horizontal tension need to be calculated based on the weight of the equipment and vibration parameters. Second, combining the node type (such as rigid node, hinged node) and material strength parameters (such as the tensile strength of bolts and the shear strength of welds) in the internal structural connection information, the load-bearing capacity reserve coefficient of each node (the ratio of the node's ultimate bearing capacity to the calculated load) is evaluated. When the load-bearing capacity reserve coefficient of a node is lower than the set safety threshold, the node is identified as a node that needs reinforcement. In addition, the overall force transmission path of the structure must be considered, and the connection nodes on the key force transmission paths must be analyzed. For example, the series nodes in the force transmission path from the antenna equipment to the support, then to the main building roof, and finally to the foundation should all be the focus of evaluation. Based on the above analysis, the beam-column nodes of the main building (especially the corner nodes that bear large bending moments), the connecting flange nodes between the antenna support and the main building, and the fixing nodes of the heavy equipment mounting racks in the equipment room are marked as key load-bearing nodes. Each key load-bearing node is assigned a unique identifier, and its location coordinates, connection type, current load-bearing capacity parameters, and corresponding load-bearing related parameters are recorded.

[0029] Step S124: Establish a mapping relationship between terrain-sensitive areas and topology adjustment parameters. The topology adjustment parameters include the direction of regional structure density adjustment and the direction of regional geometric shape adaptation. The establishment of the mapping relationship refers to the surface geometric information characteristics of the terrain-sensitive areas.

[0030] For each terrain-sensitive area, its surface geometric information features are extracted, including the curvature distribution of surface points within the area (such as mean curvature and Gaussian curvature), the rate of change of the surface normal vector, the area size, the perimeter-to-area ratio (reflecting the compactness of the area), and the three-dimensional coordinates of protruding or concave features within the area. Based on these surface geometric information features, a mapping relationship with topology adjustment parameters is established. Regarding the direction of regional structure density adjustment, if the surface of the terrain-sensitive area has a large area of ​​concavity (determined based on the rate of change of the normal vector and curvature parameters), and the concave area corresponds to a higher position of the terrain, the adjustment direction is to increase the structure density in the concave area to fill the gaps and improve stability; if the area surface is relatively flat but the gaps with the terrain are evenly distributed, the adjustment direction may be to locally reduce the structure density to reduce weight while ensuring the contact area. For the direction of regional geometric adaptation, if the edge contour of the terrain-sensitive area has a low degree of agreement with the terrain contour lines (determined by calculating the root mean square error between the contour lines and contour lines), the adjustment direction is to shift the edge contour of the area towards the terrain contour lines, with the shift amount determined according to the magnitude of the error. If the difference between the surface slope of the area and the terrain slope is large, the adjustment direction is to rotate or bend the surface of the area to reduce the slope difference to a set range. The specific implementation of the mapping relationship can be achieved by training a deep learning-based terrain-parameter mapping model, using the surface geometric information feature vector of the terrain-sensitive area as input and the topology adjustment parameters (regional structure density adjustment direction vector and regional geometric adaptation direction vector) as output. The model is trained with a large amount of labeled data to achieve accurate mapping.

[0031] Step S125: Establish a mapping relationship between the key node and the topology reinforcement parameters. The topology reinforcement parameters include the node connection strength adjustment direction and the node associated structure expansion direction. The establishment of the mapping relationship refers to the internal structural connection information characteristics of the key node.

[0032] Extract the internal structural connection information features of the key nodes, such as the type of connecting components at the node (bolts, welds, rivets), component dimensions (bolt diameter, weld thickness, rivet length), material mechanical properties of the connecting components (yield strength, elastic modulus), cross-sectional dimensions of the structural components at the node (e.g., column cross-sectional side length, beam cross-sectional height), reinforcement ratio (for concrete nodes) or material density (for metal nodes), etc. Establish a mapping relationship with topology strengthening parameters based on these features. Regarding the direction of adjusting the node connection strength, if the shear force on the connecting component (e.g., bolts) of the key node is close to its design shear strength (calculated based on material mechanical properties and component dimensions), the adjustment direction is to increase the number of bolts or increase the bolt diameter to improve shear strength; if the tensile stress of the weld at the node exceeds the limit, the adjustment direction is to increase the weld thickness or change the welding method (e.g., changing from a fillet weld to a butt weld). Regarding the expansion direction of the node-related structure, if the cross-sectional stiffness of the structural member supporting the key node (such as a beam connected to the node) is insufficient (judged based on the bending stiffness parameters calculated from the cross-sectional dimensions and the material's elastic modulus), resulting in excessive bending moment at the node, the adjustment direction is to expand the cross-sectional dimensions of the connected beam or add auxiliary support members (such as diagonal braces) to share the bending moment. If the overall structural integrity of the area where the node is located is poor (assessed through the number of connections between the node and the surrounding structure and the stiffness distribution), the adjustment direction is to expand the connecting members around the node to form a grid-like reinforced structure. Similarly, a node-parameter mapping model can be constructed, using the feature vector of the internal structural connection information supporting the key node as input and the topology reinforcement parameters (node ​​connection strength adjustment direction vector and node-related structure expansion direction vector) as output, and the mapping relationship can be established through training.

[0033] Step S126: Integrate the mapping relationship between terrain-sensitive areas and topology adjustment parameters, and the mapping relationship between key nodes and topology enhancement parameters, to form the basic framework of topology optimization guidance rules.

[0034] The mapping relationships between terrain-sensitive areas and topology adjustment parameters established in step S124 and between load-bearing key nodes and topology reinforcement parameters established in step S125 are systematically integrated. First, a unique rule identifier is assigned to each entry in both mapping relationships, and its applicable conditions are clarified (e.g., specific types of terrain-sensitive areas or load-bearing key nodes). Second, an association mechanism is established between the two mapping relationships. For example, when terrain-sensitive areas and load-bearing key nodes overlap spatially (e.g., a load-bearing key node is contained within a terrain-sensitive area), the priority order of topology adjustment parameters and topology reinforcement parameters needs to be determined. Generally, structural load-bearing requirements take precedence over terrain adaptation requirements, but terrain adaptation can be considered without affecting load-bearing safety. Then, the hierarchical structure of the basic framework is defined. The top layer is the overall rule entry point, and the next layer is divided into terrain adaptation rule branches and structural load-bearing rule branches. Each branch is further subdivided into mapping relationship entries corresponding to specific area / node types. Finally, metadata information is added to the basic framework, including the rule version number, creation time, applicable model type (such as mountain communication base station), update log, etc., to form the basic framework document of the topology optimization guidance rules. This basic framework document is stored in Extensible Markup Language (XML) format for easy subsequent reading, modification and expansion.

[0035] Step S127: Integrate the material association information in the initial 3D model data into the basic framework of the topology optimization guidance rules, and adjust the value direction of the topology adjustment parameters and topology strengthening parameters according to the structural characteristics corresponding to different materials to form the topology optimization guidance rules.

[0036] Step S1271: Extract the material association information from the initial three-dimensional model data, separate the structural units corresponding to different materials, and count the number and distribution area of ​​structural units corresponding to each material.

[0037] From the material association information of the initial 3D model data, all structural units in the model are grouped according to material type using a material ID identification and separation algorithm. For example, structural units corresponding to C30 concrete (such as the walls and load-bearing columns of the main building), structural units corresponding to HRB400 grade steel reinforcement (such as the longitudinal reinforcement and stirrups in the load-bearing columns), and structural units corresponding to 6061-T6 aluminum alloy (such as the poles and connectors of the antenna support) are separated. For each material type, the number of corresponding structural units is counted (e.g., there are 500 C30 concrete units and 2000 HRB400 steel reinforcement units), and the distribution area of ​​each structural unit is determined by the 3D coordinate range of each structural unit, generating a material distribution heatmap (based on 3D mesh units, the proportion of each material in each mesh unit is counted).

[0038] Step S1272: Analyze the structural characteristics of each material, including the compressive strength and deformation coefficient of the material, and determine the range of topological adjustments that the structural unit corresponding to each material can withstand.

[0039] For each isolated material, its structural property parameters are obtained by querying material mechanics databases or conducting material tests. For compressive strength, the standard value of cubic compressive strength (e.g., 30 MPa for C30 concrete) and the design value of axial compressive strength are obtained. For deformation coefficients, parameters such as elastic modulus (e.g., approximately 69 GPa for 6061-T6 aluminum alloy), Poisson's ratio, and ultimate tensile deformation rate are obtained. Based on these structural property parameters, combined with the geometric dimensions of the structural unit (e.g., cross-sectional area, length), the maximum allowable deformation and maximum allowable stress value of the structural unit corresponding to each material under different topology adjustment operations (e.g., tension, compression, bending, shear) are calculated using the finite element method of structural mechanics. Based on the maximum allowable deformation and stress value, the range of topology adjustment that the structural unit of that material can withstand is determined. For example, the adjustment range of HRB400 steel bar unit in the tensile direction is -5% (shortening) to +3% (elongation) of the original length. Exceeding this range may lead to yielding or fracture.

[0040] Step S1273: For the topology adjustment parameters corresponding to the terrain-sensitive area, adjust the value range of the structural density adjustment direction according to the structural characteristics of different materials in the terrain-sensitive area. The upper limit of the value range is increased in areas where the material compressive strength meets the compressive strength threshold set in the topology optimization guidance rules, and the lower limit of the value range is decreased in areas where the material deformation coefficient meets the deformation coefficient threshold set in the topology optimization guidance rules.

[0041] For terrain-sensitive areas, firstly, all material types and their distribution areas within the area are identified (based on the results of step S1271). Then, the compressive strength parameters of each material are compared with the compressive strength threshold set in the topology optimization guidance rules (determined according to engineering safety standards and material usage specifications). If the compressive strength of a material in a certain area is higher than the threshold, it indicates that the structure in that area has greater adjustment potential in the compression direction. Therefore, the upper limit of the density increase range in the density adjustment direction of that area is increased (e.g., from the original upper limit of 10% to 15%), allowing more structural material to be added to that area to fill terrain gaps. At the same time, the deformation coefficient of each material (e.g., the reciprocal of the elastic modulus, reflecting the flexibility of the material) is compared with the set deformation coefficient threshold. If the deformation coefficient of a material in a certain area is higher than the threshold (i.e., the material has greater flexibility), it is prone to excessive deformation during topology adjustment. Therefore, the lower limit of the density reduction range in the density adjustment direction of that area is lowered (e.g., from the original lower limit of -5% to -3%), reducing the risk of excessive deformation due to excessive material reduction. The adjustment process requires combining the initial value range of the topology adjustment parameters for terrain-sensitive areas and independently correcting the value range of each material distribution sub-region.

[0042] Step S1274: For the topology reinforcement parameters corresponding to the bearing key nodes, adjust the value range of the connection strength adjustment direction according to the material and structural characteristics of the structural units associated with the bearing key nodes. The upper limit of the value range corresponding to the associated structural units whose material compressive strength meets the compressive strength threshold set in the topology optimization guidance rules is increased, and the lower limit of the value range corresponding to the associated structural units whose material deformation coefficient meets the deformation coefficient threshold set in the topology optimization guidance rules is decreased.

[0043] For critical load-bearing nodes, identify all structural units directly associated with them (such as bolts, welds, connected beams, columns, etc.) and their material types. Compare the compressive strength of the materials of these associated structural units with the compressive strength threshold set in the topology optimization guidance rules. If the compressive strength is high (exceeding the threshold), it indicates that the associated structural unit has a large margin in bearing compressive loads. Therefore, the upper limit of the strength enhancement range in the connection strength adjustment direction can be increased (e.g., the upper limit of bolt diameter increase is increased from 2mm to 3mm). At the same time, compare the deformation coefficient of the associated structural unit with the set deformation coefficient threshold. If the deformation coefficient is high (the material is softer), it is prone to large deformation under stress. In this case, the lower limit of the strength reduction range in the connection strength adjustment direction needs to be reduced (e.g., the lower limit of weld thickness reduction is reduced from 1mm to 0.5mm) to avoid uncontrolled deformation due to excessive strength reduction. For the extension direction of the node-related structure, if the compressive strength of the material in the extension area is high, the upper limit of the cross-sectional size adjustment of the extension structure can be appropriately increased; if the material deformation coefficient is high, the lower limit of the length adjustment of the extension structure needs to be controlled to prevent resonance or instability.

[0044] Step S1275: Record the adjustment range of the topology adjustment parameters and topology reinforcement parameters corresponding to each material, and form a material-parameter adjustment comparison table.

[0045] The adjustments to the topology adjustment parameters (regional structural density adjustment direction, regional geometric shape adaptation direction) and topology strengthening parameters (node ​​connection strength adjustment direction, node associated structure expansion direction) for each material in steps S1273 and S1274 are recorded in detail. The records include the material ID, material name, the type of parameter involved in the adjustment (e.g., the upper limit of the regional structural density adjustment direction), the original value range, the adjusted value range, and the basis for the adjustment (e.g., compressive strength value, deformation coefficient value). These records are then compiled into a two-dimensional tabular material-parameter adjustment comparison table, where rows represent different materials and columns represent different parameter adjustment items and their value ranges before and after the adjustment.

[0046] Step S1276: Integrate the material-parameter adjustment lookup table into the basic framework of the topology optimization guidance rules, and add the corresponding material adaptation value range under each topology adjustment parameter and topology enhancement parameter item in the basic framework to form the topology optimization guidance rules.

[0047] Open the basic framework (XML format document) of the topology optimization guidance rules formed in step S126. Under the definition entries of each topology adjustment parameter and topology reinforcement parameter, add a "Material Adaptation Value Range" sub-node. According to the material-parameter adjustment lookup table, write the adjusted value range corresponding to different materials into this sub-node. For example, under the parameter entry "Upper Limit of Regional Structure Density Adjustment Direction", add a value range of "5%-15%" for C30 concrete material and a value range of "3%-10%" for 6061-T6 aluminum alloy material. At the same time, add material priority judgment logic to the rules. When a terrain-sensitive area or load-bearing key node contains multiple materials, determine the preferred material adaptation value range based on the structural characteristics of the materials (such as compressive strength from high to low). After completing the addition of material adaptation value ranges for all parameter entries, perform syntax checks and logical consistency verification on the entire rule document (such as avoiding conflicts in the value ranges of the same parameter under different materials), and finally form a complete topology optimization guidance rule.

[0048] Step S130: Perform topology optimization operation on the initial three-dimensional model data according to the topology optimization guidance rules. During the topology optimization operation, the adjustment trajectory of the internal structural connection relationship of the model is recorded synchronously to obtain the topology-optimized three-dimensional model intermediate frame and the corresponding structural adjustment trajectory information.

[0049] In mountainous communication base station scenarios, topology optimization is performed on the initial 3D model data based on the aforementioned topology optimization guidance rules. This operation is a dynamic adjustment process, involving adjustments to the structural morphology and density of terrain-sensitive areas, as well as adjustments to the connection strength and associated structural expansion of key nodes. During the adjustment process, every change in the internal structural connection relationships of the model needs to be tracked and recorded in real time, including which connection nodes are modified, how the connection methods change, and the addition or removal of structural units. These records constitute the structural adjustment trajectory information. After the topology optimization operation is completed, the resulting intermediate framework of the 3D model should accurately reflect the geometry after terrain adaptation and the connection state after structural load-bearing enhancement.

[0050] Step S131: Import the initial 3D model data into the topology optimization processing module, and locate the terrain-sensitive areas in the initial 3D model data according to the terrain-sensitive area marking in the topology optimization guidance rules.

[0051] The initial 3D model data (usually in standard formats such as FBX and OBJ, or specialized BIM formats such as IFC), containing model surface geometry, internal structural connection information, material association information, and scene association features, is imported into a professional topology optimization processing module (such as a module developed based on finite element analysis software). In this module, the topology optimization guidance rule document is read, and the marking information for terrain-sensitive areas is parsed, including the unique identifier of each terrain-sensitive area, the 3D boundary coordinate range, and the corresponding terrain-related parameter features. A spatial coordinate matching algorithm is used to locate the geometric regions in the imported initial 3D model data that match this marking information. Specifically, the 3D coordinates of all structural elements in the model data are compared with the boundary coordinate range of the terrain-sensitive areas. If the center point or all vertices of a structural element are within this boundary range, the structural element is determined to belong to that terrain-sensitive area. This process is repeated for all terrain-sensitive area markings to achieve precise positioning in the initial 3D model data. Each terrain-sensitive area is then highlighted in the 3D view with different colors or transparency for subsequent operations.

[0052] Step S132: Based on the topology adjustment parameters corresponding to the terrain-sensitive area in the topology optimization guidance rules, perform a structure density adjustment operation on the located terrain-sensitive area, and record the density change value and change order of each structural unit in the terrain-sensitive area during the adjustment process.

[0053] For each identified terrain-sensitive area, the corresponding topology adjustment parameters are read from the topology optimization guidance rules. The focus is on extracting the regional structural density adjustment direction parameters (e.g., increasing density, decreasing density, maintaining density) and the value range under that direction (combined with the value range after material adaptation). The structural density adjustment operation is implemented using the finite element density method, discretizing the terrain-sensitive area into a large number of three-dimensional mesh elements (e.g., tetrahedral or hexahedral elements). Each mesh element is assigned a density variable (typically ranging from 0 to 1, where 0 indicates complete deletion and 1 indicates complete retention). Based on the density adjustment direction in the topology adjustment parameters, the objective function of the density variable is set. For example, if the adjustment direction is to increase density to fill terrain gaps, the objective function is to maximize the mesh element density in the gap region; if the adjustment direction is to decrease density to reduce weight, the objective function is to minimize the overall density of mesh elements within the region while satisfying stiffness constraints. Simultaneously, considering the surface geometric information features (such as curvature and normal vector) and material-related information (density adjustment range obtained through a material-parameter adjustment lookup table) of terrain-sensitive areas, constraints are added to the objective function, such as density change gradient constraints (to avoid stress concentration caused by excessive density differences between adjacent units) and minimum size constraints (to prevent the generation of overly fine structures). By solving the objective function, the optimized density value of each mesh unit is obtained. This density value is compared with the initial density value, and the density change value (optimized density value minus initial density value) is calculated. During the adjustment process, the density change value of each structural unit (mesh unit) is recorded according to the order of finite element iterative solution (e.g., 1st iteration, 2nd iteration, etc.), forming a density change record. The record includes the unit ID, initial density, density after each iteration, final density, density change value (final density - initial density), and the corresponding iteration number (change order).

[0054] Step S133: Locate the key nodes in the initial 3D model data according to the key node marking in the topology optimization guidance rules.

[0055] Similar to the location process for terrain-sensitive areas, the system reads the marking information of key load-bearing nodes from the topology optimization guidance rules, including the unique number, 3D coordinate position, connection type, and list of associated structural unit IDs for each key load-bearing node. In the topology optimization processing module, key load-bearing nodes are located in the initial 3D model data through node coordinate matching and structural unit association queries. Specifically, first, a precise search is performed in the model's node database based on the node's 3D coordinates to find candidate nodes with coordinate errors within a set range (e.g., 0.01mm). Then, the connection type (e.g., rigid or hinged) of the candidate nodes is checked to ensure it matches the markings in the rules. Finally, the list of associated structural unit IDs for the candidate nodes is queried to verify whether these structural units correspond to the actual structural units in the model (e.g., checking unit type and material matching). Through these steps, all key load-bearing nodes are located in the initial 3D model data and marked in the 3D view with special symbols (e.g., red spheres), while their numbers and key parameters are displayed.

[0056] Step S134: Based on the topology strengthening parameters corresponding to the key nodes in the topology optimization guidance rules, perform connection strength adjustment operations on the located key nodes. During the adjustment process, record the change values ​​and order of the connection strength between the key nodes and the associated structural units.

[0057] For each identified critical load-bearing node, its corresponding topology strengthening parameters are retrieved from the topology optimization guidance rules. The focus is on extracting the node connection strength adjustment direction parameters (e.g., increasing strength, decreasing strength, maintaining strength) and their value range (combined with the range after material adaptation). Connection strength adjustment operations are performed on the connecting components (e.g., bolts, welds, rivets) between the node and associated structural units. Based on the connection strength adjustment direction, the specific content of the adjustment is determined. For example, if the direction is to increase strength and the connecting component is a bolt, possible adjustments include increasing the bolt diameter, increasing the number of bolts, or replacing bolts with higher strength bolts; if it is a weld, possible adjustments include increasing the weld thickness, adjusting the weld type, or improving the welding quality level. Through structural mechanics calculations (e.g., shear capacity calculation of bolt groups, tensile strength calculation of welds), the change in connection strength under each adjustment method is determined (e.g., the increase in load-bearing capacity after increasing bolt diameter). During the adjustment process, record the connection strength parameters (such as shear capacity and tensile capacity) before and after each adjustment according to the order of operation (e.g., adjust the bolt diameter first, then increase the number of bolts). Calculate the change in connection strength (strength after adjustment - strength before adjustment) to form a connection strength change record. The record includes the node number, associated structural unit ID, connection member type, adjustment method, strength before adjustment, strength after adjustment, strength change value, and adjustment sequence number.

[0058] Step S135: During the process of adjusting the structural density and the connection strength of key load-bearing nodes in the terrain-sensitive area, the change nodes of the internal structural connection relationship of the initial three-dimensional model data and the connection status before and after the change are recorded simultaneously to form a structural connection change sequence.

[0059] When performing structural density adjustment and load-bearing critical node connection strength adjustment operations in terrain-sensitive areas, the topology optimization module monitors changes in the structural connection relationships within the model in real time. When structural density adjustment causes the density value of a mesh element to change from greater than 0 to 0 (element deletion), the connection relationship between that mesh element and its adjacent elements will be severed; when the density value changes from 0 to greater than 0 (element addition), a new connection relationship will be established with surrounding elements; when the density value changes to a non-zero value, it may lead to adjustments in the connection stiffness with adjacent elements. Similarly, adjustments to the connection strength of load-bearing critical nodes may also lead to changes in connection relationships. For example, adding bolted connections will add new connections between nodes and components, and deleting welded joints will break existing connections. For these changes, the changed node (the ID of the structural element or node whose connection relationship has changed), the change timestamp (relative to the start time of the optimization operation), the connection status before the change (such as connection type, connection stiffness value, and component IDs involved in the connection), and the connection status after the change must be recorded. The above records are arranged in chronological order of the changes to form a structural connection change sequence, with each sequence item containing all the above change information.

[0060] Step S136: Integrate density change records of terrain-sensitive areas, connection strength change records of key nodes, and structural connection change sequences to form structural adjustment trajectory information.

[0061] Step S1361: Mark the density change records of the terrain-sensitive area with a time axis, and add a time sequence identifier to each density change value according to the execution order of the topology optimization operation to form a time-seriesd density change record.

[0062] Extract the density change value and corresponding iteration step number for each structural unit from the density change records of the terrain-sensitive area. Obtain the timestamp (accurate to milliseconds) of the start of each iteration step from the log file of the topology optimization processing module. Establish a one-to-one correspondence between the iteration step number and the timestamp, and then add a corresponding time sequence identifier (such as a timestamp or a time-stamp-based sequence number, such as T1, T2...Tn) to each density change value of each structural unit. For example, if the density change value of a structural unit in the 5th iteration (corresponding to timestamp 10:05:30.123) is 0.3, it is marked as (Unit ID: U123, Change Value: 0.3, Time Sequence Identifier: T5). Sort all density change records with added time sequence identifiers according to the time sequence identifier to form a time-seriesd density change record.

[0063] Step S1362: Mark the connection strength change records of the bearing key nodes with node numbers, assign a unique number to each bearing key node, and associate the connection strength change value with the corresponding bearing key node number to form a node-based strength change record.

[0064] Extract information from the connection strength change records of all key nodes, and assign a unique, non-repeating node number (e.g., K1, K2...Km) to each key node. This number should match the node identifier in the topology optimization guidance rules. Replace the node information in each connection strength change record with the corresponding node number, ensuring that the strength change value, adjustment method, and other information are correctly associated with the node number. For example, the original record (Node Name: Antenna Support Flange Node, Strength Change Value: +20kN, Adjustment Method: Increase Bolt Diameter) is replaced with (Node Number: K3, Strength Change Value: +20kN, Adjustment Method: Increase Bolt Diameter). Sort all connection strength change records with associated node numbers according to the node number to form a node-based strength change record.

[0065] Step S1363: Classify the structural connection change sequence by change type, and divide the change events in the structural connection change sequence into three categories: connection addition, connection deletion and connection adjustment. Add a type identifier to each type of change event to form a classified change sequence.

[0066] Traverse each change record in the structural connection change sequence and analyze the connection status before and after the change. If there is no connection before the change but a connection exists after the change, it is classified as a "connection addition" type; if there is a connection before the change but no connection after the change, it is classified as a "connection deletion" type; if there is a connection before and after the change, but the connection type, connection stiffness, or connection component changes, it is classified as a "connection adjustment" type. Add a corresponding type identifier for each type of change event, such as "add", "delete", "adjust", or abbreviated as "A", "D", "M". Add a type identifier field to each change record, for example, (Change node: U456, State before change: No connection, State after change: Hinged with U789, Type identifier: A). Arrange all change sequences with added type identifiers in their original chronological order to form a categorized change sequence.

[0067] Step S1364: Establish the association between time-series density change records and categorized change sequences. Determine the time overlap points of density changes and structural connection changes based on the time sequence identifiers. Record the density change values ​​and corresponding change events at the time overlap points.

[0068] Extract the time sequence identifier set (T1, T2...Tn) from the time-series density change records and the change event timestamp set from the categorized change sequences. Using a timestamp matching algorithm, find time overlap points where the timestamp corresponding to the time sequence identifier is the same as or within a set time difference range (e.g., ±100ms). For each time overlap point, obtain the density change values ​​of all structural units under that time sequence identifier, as well as the change event details (change node, change type, and pre- and post-change states) corresponding to that timestamp in the categorized change sequence. Link and record the above information to form a linked item (time sequence identifier, density change value list, change event list). For example, if the time sequence identifier T5 corresponds to the timestamp 10:05:30.123, and there is a connection addition event (nodes U123 and U456 are connected), and five structural units undergo density changes at T5, then it is recorded as (T5, [(U1:0.2), (U2:-0.1), ...], [(changed nodes: U123-U456, type: A, state change: ...)]).

[0069] Step S1365: Establish the association between node-based strength change records and categorized change sequences. Based on the number of the key load-bearing nodes, determine the node association points for the connection strength changes of key load-bearing nodes and structural connection changes, and record the connection strength change values ​​and corresponding change events at the node association points.

[0070] Extract the set of key bearing node numbers (K1, K2...Km) from the node intensity change record and the set of change node IDs from the categorized change sequence. For each key bearing node number, find all structural unit IDs associated with it in the initial 3D model data (obtained from topology optimization guidance rules or model database). If the change node ID involved in a change event in the categorized change sequence belongs to the structural unit ID associated with that key bearing node, then it is determined that there is a node association point between that change event and that key bearing node. For each node association point, obtain the connection strength change value of that key bearing node in the node intensity change record, and the corresponding change event details in the categorized change sequence. Record the above information together to form an association item (node ​​number, connection strength change value, change event list). For example, if the structural unit associated with key bearing node K3 includes U789, and there is a connection adjustment event for U789 in the categorized change sequence, then it is recorded as (K3, +20kN, [(change node: U789, type: M, state change: ...)]).

[0071] Step S1366: Integrate the time-series density change records, node-based intensity change records, categorized change sequences, and their respective association records with the categorized change sequences to form structural adjustment trajectory information. The structural adjustment trajectory information includes associated data in the time dimension, node dimension, and change type dimension.

[0072] Create a structured data model to store structural adjustment trajectory information. This model contains multiple data dimensions. The time dimension uses a time sequence identifier as the primary key, linking time-series density change record segments, corresponding categorized change sequence events, and time-overlapping point association records at that time point. The node dimension uses the key node number as the primary key, linking node-level intensity change record segments, corresponding categorized change sequence events, and node-related point association records for that node. The change type dimension uses a change type identifier (A, D, M) as the primary key, linking all categorized change sequence events of that type, corresponding time-series density change record segments (via time-overlapping points), and node-level intensity change record segments (via node-related points). All the above records (time-series density change records, node-level intensity change records, categorized change sequences, time-overlapping point association records, and node-related point association records) are organized and stored according to this data model. This can be implemented using a relational database (such as MySQL) or a graph database (such as Neo4j), ultimately forming structural adjustment trajectory information containing multi-dimensional associated data of time, nodes, and change types.

[0073] Step S137: After completing all topology optimization operations, a topology-optimized 3D model intermediate frame is generated. The topology-optimized 3D model intermediate frame retains the adjusted geometry of the terrain-sensitive area and the adjusted connection state of the bearing key nodes.

[0074] After the structural density adjustment of terrain-sensitive areas, the connection strength adjustment of key nodes, and other topology optimization operations (such as regional geometric shape adaptation and node association structure expansion, which are similar to steps S132 and S134 and are executed according to the regional geometric shape adaptation direction in the topology adjustment parameters and the node association structure expansion direction in the topology strengthening parameters, respectively) are completed, the topology optimization processing module organizes and reconstructs the adjusted model data. This process includes deleting mesh cells with density values ​​below a set threshold (e.g., 0.1), retaining and optimizing the shape of cells with density values ​​above the threshold, solidifying the adjusted connection component size and type of key nodes, updating the model surface geometry to reflect the adjusted shape (e.g., filling concave areas and smoothing edge contours), and updating the internal structural connection information to record new connection relationships and strength parameters. The generated topology-optimized 3D model intermediate framework is stored in a format compatible with the initial 3D model data, and all adjusted geometric shape parameters of terrain-sensitive areas (e.g., adjusted volume, surface area, centroid coordinates) and adjusted connection status parameters of key nodes (e.g., connection strength values, safety reserve coefficients) are marked in the model attributes for use in subsequent steps.

[0075] Step S140: Based on the topology-optimized 3D model intermediate frame and the corresponding structural adjustment trajectory information, formulate a structural simplification strategy. The structural simplification strategy matches the structural distribution pattern of the topology-optimized 3D model intermediate frame and associates the key structural adjustment nodes recorded in the structural adjustment trajectory information.

[0076] After the topology optimization of the mountain communication base station model is completed, a structural simplification strategy needs to be formulated to reduce the complexity of the model and facilitate subsequent storage, transmission, and application (such as virtual simulation and remote maintenance). The formulation of the structural simplification strategy should be based on the structural characteristics of the intermediate frame of the topology-optimized 3D model (such as surface geometric distribution and internal connection rules) and key adjustment nodes in the structural adjustment trajectory information (such as areas with significant density changes and nodes with frequent changes in connection relationships), ensuring that the simplification process does not damage the key structural characteristics and load-bearing capacity of the model.

[0077] Step S141: Extract the surface geometry information of the intermediate frame of the topology-optimized 3D model, identify the regions in the surface geometry information where the curvature change value is within the smooth interval set in the topology optimization guidance rules, and mark them as smooth curvature regions.

[0078] Surface geometric information is extracted from the intermediate framework of the topology-optimized 3D model, including the 3D coordinate point set, normal vector data, and connection relationships of triangular or quadrilateral facets for all surface structural units. Curvature calculation algorithms (such as average curvature calculation based on mesh vertices or discrete curvature calculation based on facet normals) are used to calculate the curvature change value (e.g., Gaussian curvature, absolute value of average curvature) for each vertex or facet on the model surface. A set curvature smoothing interval is read from the topology optimization guidance rules (e.g., the absolute value of average curvature is less than a certain threshold, which is determined based on the surface detail requirements of subsequent model applications; for example, the threshold can be larger for visualization applications and smaller for engineering analysis applications). The calculated curvature change values ​​are compared with this smoothing interval. If the curvature change values ​​of all vertices or facets within a certain surface region are within this interval, and the area of ​​the region is greater than a set minimum region area threshold (to avoid marking excessively small flat areas), then the region is marked as a smooth curvature region. The marking process requires recording parameters such as the boundary vertex coordinates, the number of facets contained within the region, and the average curvature value.

[0079] Step S142: Extract the internal structural connection information of the intermediate frame of the topology-optimized 3D model, identify the structural connection paths in the internal structural connection information that are not directly related to the key nodes, and mark them as non-critical connection paths.

[0080] Extract the internal structural connection information of the intermediate frame of the topology-optimized 3D model, including the type of all connection nodes, the start and end structural unit IDs of the connection paths, the intermediate node IDs on the paths, the length of the connection paths (the straight-line distance in 3D space from the start to the end point or the actual length along the path), and the stiffness parameters of the paths. Obtain the numbers of all key nodes and their associated structural unit IDs from the topology optimization guidance rules. Using graph theory algorithms (such as Breadth-First Search or Depth-First Search), starting from the structural units associated with the key nodes, traverse all structural connection paths that are directly connected (first-level connections) and indirectly connected (multi-level connections). These paths are defined as key connection paths. The remaining untraversed structural connection paths, i.e., paths that are not directly or indirectly associated with the key nodes, are identified as non-key connection paths. Mark the non-key connection paths and record their start and end point IDs, path length, number of connection nodes, and list of associated structural unit IDs.

[0081] Step S143: Analyze the density change records of terrain-sensitive areas in the structure adjustment trajectory information, determine the sub-regions whose values ​​after density change are within the redundancy interval set in the topology optimization guidance rules, and mark them as density redundant sub-regions.

[0082] Extract time-series density change records from structural adjustment trajectory information, focusing on the final density change values ​​(i.e., optimized density values) of each structural unit within terrain-sensitive areas. Read the defined density redundancy intervals from the topology optimization guidance rules (e.g., density values ​​below a certain threshold, determined based on material structural characteristics and model load-bearing requirements, ensuring structural units within this interval contribute minimally to overall stiffness). For each terrain-sensitive area, divide it into smaller sub-regions (e.g., sub-regions based on spatial grids, each containing multiple structural units). Calculate the average final density value of structural units within each sub-region (arithmetic mean or weighted average of all unit density values, weighted by unit volume). If the average final density value of a sub-region falls within the density redundancy interval, and the volume of that sub-region exceeds the set minimum sub-region volume threshold, then mark that sub-region as a density-redundant sub-region. The marking process requires recording parameters such as the sub-region's 3D boundary coordinates, the number of structural units it contains, and its average density value.

[0083] Step S144: Analyze the structural connection change sequence in the structural adjustment trajectory information, identify structural units that do not affect the overall structural connection after the change, and mark them as invalid structural units.

[0084] The structural adjustment trajectory information is used to extract categorized change sequences and corresponding temporal density change records. First, structural units that have undergone "connection deletion" or "connection adjustment" in the structural connection change sequence and have no connection with other structural units (i.e., isolated units) are identified. Second, combined with the temporal density change records, structural units with negative density changes (density reduction) and final density values ​​close to 0 (but not completely deleted, possibly due to algorithm accuracy or minimum size constraints), and which did not participate in any effective connections in the change sequence (i.e., their connection changes do not contribute to the force transmission path of the surrounding structure). Using a rapid structural mechanics evaluation method (e.g., calculating the stiffness change rate of the overall structure after deleting the unit), if the stiffness change rate is lower than a set impact threshold (e.g., less than 0.1%), the structural unit is determined to have no impact on the overall structural connections. These two types of structural units are marked as invalid structural units, and their ID, 3D coordinate center, material type, associated change events, and other parameters are recorded.

[0085] Step S145: Determine the geometric simplification direction based on the surface geometric features of the gently curvature region. The geometric simplification direction includes the surface unit merging method and edge contour simplification method of the gently curvature region.

[0086] Step S1451: Extract the surface element parameters from the surface geometry information of the gently curvature region. The surface element parameters include the area of ​​the surface element and the included angle between adjacent surface elements.

[0087] Extract parameters from all surface elements (such as triangular and quadrilateral facets) within the marked, gently curving regions. For each element, calculate its area (using the polygon area formula based on the vertex coordinates). For each element, identify all adjacent elements sharing an edge and calculate the angle between the element's normal vector and the normal vectors of each adjacent element (i.e., the angle between adjacent elements, calculated using the dot product formula, taking the absolute value of either acute or obtuse angle). Record the area of ​​each element, a list of adjacent element IDs, and the corresponding angle values ​​to form a surface element parameter table.

[0088] Step S1452: Statistically analyze the distribution of surface unit parameters within the gently curvature region, and identify small surface unit clusters with areas smaller than the surface unit area threshold set in the topology optimization guidance rules, as well as adjacent surface unit groups with included angles smaller than the included angle threshold set in the topology optimization guidance rules.

[0089] Statistical analysis is performed on the area data in the surface element parameter table for regions with gentle curvature, and area distribution histograms or cumulative distribution curves are plotted. A surface element area threshold is read from the topology optimization guidance rules (this threshold is set according to the model simplification requirements; surface elements with an area smaller than this threshold are considered small surface elements). All surface elements with an area smaller than this threshold are selected, and then small surface elements that are spatially adjacent (e.g., sharing vertices or edges) are clustered into clusters using a spatial clustering algorithm (such as the distance-based DBSCAN algorithm). Each cluster is a small surface element cluster. Simultaneously, the angle data between adjacent surface elements in the surface element parameter table is statistically analyzed, and an angle threshold is read from the topology optimization guidance rules (this threshold is set according to the model surface smoothness requirements; adjacent surface elements with an angle smaller than this threshold can be considered approximately coplanar). All pairs of adjacent surface elements with an angle smaller than this threshold are selected to form adjacent surface element groups.

[0090] Step S1453: Analyze the spatial distribution pattern of the small surface unit cluster, determine the number of shared edges and spatial relationships of the surface units within the small surface unit cluster, and design the execution order of surface unit merging based on the number of shared edges and spatial relationships. The execution order is based primarily on the number of shared edges reaching the threshold set in the topology optimization guidance rules, and secondarily on the spatial relationships meeting the adjacent distance requirements set in the topology optimization guidance rules.

[0091] For each small facet cluster, analyze the connectivity between facets within the cluster and count the number of shared edges between each facet and other facets in the cluster (e.g., a triangular facet may share 1, 2, or 3 edges with adjacent facets). Read the shared edge threshold (e.g., 2 edges, indicating a close connection between two facets) and adjacent distance requirements (e.g., the distance between the center points of facets is less than a certain value) from the topology optimization guidance rules. When designing the execution order for facet merging, first process facet pairs whose shared edge count reaches the shared edge threshold, as these facets are closely connected and have minimal impact on the surface morphology after merging. If the number of shared edges is the same, prioritize merging facet pairs whose spatial location meets the adjacent distance requirements, i.e., facet pairs with smaller center point distances are merged first. Sort all possible facet pairs within the cluster according to the above priority to form a list of facet merging execution orders.

[0092] Step S1454: Analyze the angle distribution characteristics of adjacent face unit groups, determine the adjacent face unit pairs with the smallest angle, and design the cutting path direction for simplifying the edge contour based on the angle size.

[0093] For adjacent face element groups, count the included angle values ​​of all adjacent face element pairs and find the pair with the smallest included angle (there can be multiple pairs). For each pair of adjacent face element pairs with the smallest included angle, calculate the direction vector of their shared edge (based on the 3D coordinates of the two endpoints of the edge). Based on the size of the included angle, design a cutting path direction to simplify the edge contour: if the included angle is extremely small (close to 0 degrees, i.e., approximately coplanar), the cutting path direction can be along the perpendicular direction of the shared edge, merging the two face elements into a larger face element; if the included angle is small but not 0, the cutting path direction can be along the angle bisector of the normal vectors of the two face elements to smoothly transition the edges of the two face elements. The cutting path direction needs to be represented by a 3D direction vector.

[0094] Step S1455: Determine the face unit merging method according to the execution order of face unit merging. The face unit merging method includes performing a merging operation on small face unit clusters whose number of shared edges reaches the threshold of the number of shared edges set in the topology optimization guidance rules, and performing a merging operation on small face unit clusters whose spatial location meets the adjacent distance requirements set in the topology optimization guidance rules.

[0095] Based on the face unit merging execution order designed in step S1453, specific merging operation methods are formulated. For small face unit clusters where the number of shared edges reaches the shared edge threshold, the merging operation method is as follows: merge the face unit pairs ranked first in the execution order list. The vertex coordinates of the merged new face unit are calculated by weighted average of the vertex coordinates of the original face units (the weight can be determined according to the area of ​​the original face unit or its distance from the center). The normal vector of the new face unit is taken as the average of the normal vectors of the original face units. After merging, delete the original face units and update the face unit connection relationships. For small face unit clusters where the spatial location meets the adjacent distance requirements, the merging operation method is similar, but when calculating the vertex coordinates of the new face unit, the proximity of the spatial location needs to be considered, and vertices that are closer should be assigned higher weights. The attribute inheritance rules (such as material, color, etc.) of the merged new face unit need to be clearly defined in the merging method.

[0096] Step S1456: Determine the edge contour simplification method based on the cutting path direction of the edge contour simplification. The edge contour simplification method includes contour line smoothing along the direction of minimum included angle and the elimination of redundant contour points.

[0097] Based on the cutting path direction designed in step S1454, an edge contour simplification method is formulated. The contour smoothing along the direction of minimum included angle is specifically as follows: near the shared edge of adjacent face unit pairs with the smallest included angle, a set of three-dimensional coordinate points on the contour line is collected; based on the cutting path direction vector, this set of points is smoothed using a curve fitting algorithm (such as B-spline curve fitting or Bézier curve fitting) to generate a new smooth contour curve, replacing the original contour line which may contain broken lines or small protrusions. The method for eliminating redundant contour points is as follows: a distance threshold is set, and the vertical distance from each original contour point on the smoothed contour curve to the curve is calculated. If the distance of a point is greater than the threshold, the point is retained as a control point of the curve; if the distance is less than the threshold, it is determined to be a redundant contour point and eliminated. After elimination, the contour curve is redefined using the retained control points.

[0098] Step S1457: Integrate the surface unit merging method and the edge contour simplification method to form the geometric simplification direction corresponding to the gently curvature region. By comparing the surface geometric parameters of the gently curvature region before and after merging and simplification, adjust the merging boundary and the simplified contour so that the surface geometry of the processed region conforms to the geometric characteristics of the original region.

[0099] The surface unit merging and edge contour simplification methods are integrated into a single, ordered workflow. This workflow clarifies whether surface unit merging or edge contour simplification is performed first (typically, small surface unit clusters are merged first, followed by edge contour simplification), and defines the transition conditions between the two operations (e.g., the edge contour of the merged region needs to be re-extracted and simplified). In the integrated geometric simplification process, a verification and adjustment mechanism is added: after each merging or simplification operation, the surface geometric parameters of the processed region (e.g., area, volume, average curvature, boundary length) are calculated and compared with the parameters before processing. If the parameter changes exceed the set allowable deviation range (e.g., area change rate greater than 5%), the merging boundary is adjusted back (e.g., reducing the merging range) or the contour is simplified (e.g., retaining more contour points) until the surface geometry of the processed region remains consistent with the original region in key features (e.g., approximate shape, relative position, overall size), removing only redundant details.

[0100] Step S146: Determine the connection simplification direction based on the connection characteristics of non-critical connection paths. The connection characteristics include the length of the connection path and the number of associated structural units. The connection simplification direction includes the deletion method of non-critical connection paths and the integration method of associated structural units.

[0101] Step S1461: Extract the connection path length and the number of associated structural units from the connection features of the non-critical connection path, and establish a correlation table between the connection path length and the number of associated structural units.

[0102] From the records marked as non-critical connection paths, extract the connection path length (e.g., the actual 3D length along the path) and the number of associated structural units (e.g., the total number of structural units connected by the path, including units involved in the start, end, and intermediate nodes). Organize each non-critical connection path's unique identifier (e.g., path ID), connection path length, and number of associated structural units into a two-dimensional table, i.e., a table relating connection path length to the number of associated structural units. The table's column headers are Path ID, Connection Path Length, and Number of Associated Structural Units.

[0103] Step S1462: Analyze the association table, filter out non-critical connection paths whose connection path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules, and mark the non-critical connection paths separately.

[0104] The path length threshold (longer paths may be easier to simplify) and the cell number threshold (paths with fewer associated cells are less important) are read from the topology optimization guidance rules. For each record in the association table, the path length is compared to the path length threshold, and the number of associated structural cells is compared to the cell number threshold. If both conditions are met, the non-critical connection path is determined to be a high-priority deletion path and is marked separately (e.g., marked as "Type A").

[0105] Step S1463: Analyze the association table, filter out non-critical connection paths whose connection path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules, and mark this type of non-critical connection path separately.

[0106] Similarly, the two thresholds mentioned above are read from the topology optimization guidance rules. For each record in the association table, compare whether the connection path length is less than or equal to the path length threshold, and whether the number of associated structural units is greater than or equal to the unit number threshold. If both conditions are met, it is determined that although the non-critical connection path is non-critical, it is associated with a large number of structural units and may need to be handled with caution. It should be marked separately (e.g., marked as "Type B").

[0107] Step S1464: For non-critical connection paths whose path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules, analyze the distance relationship between such non-critical connection paths and surrounding critical connection paths, and design the structure processing method after deletion based on whether the distance exceeds the transition structure supplementation threshold set in the topology optimization guidance rules.

[0108] For non-critical connection paths labeled "Type A", extract their 3D coordinate path data (3D coordinates of each point on the path). Simultaneously, extract the 3D coordinate path data of all surrounding critical connection paths from the critical connection paths. Analyze the distance relationship between "Type A" paths and surrounding critical connection paths using spatial distance calculation algorithms (such as calculating the minimum distance between two paths, or the average distance from each point on the path to the critical path). Read the transition structure supplementation threshold from the topology optimization guidance rules (if the distance exceeds this threshold, structural discontinuity may occur after path deletion, requiring the addition of a transition structure). If the distance exceeds this threshold, the deleted structure is handled by adding a simplified transition structure (such as a slender connecting rod or a small transition node) between the original path's start and end points to ensure spatial continuity; if the distance does not exceed this threshold, the deleted structure is handled by directly deleting the path without adding a transition structure, as the surrounding critical connection paths already provide sufficient spatial support or connection.

[0109] Step S1465: For non-critical connection paths whose path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules, analyze the degree of indirect association between the structural units associated with such non-critical connection paths and the key nodes they carry. Based on whether the degree of indirect association reaches the degree of association threshold set in the topology optimization guidance rules, design a method for selecting retained paths.

[0110] For non-critical connection paths marked "Type B", graph theory algorithms are used to analyze the degree of indirect association between the associated structural units and the critical nodes. Specifically, a structural unit association tree is constructed with the critical node as the root node. The depth (number of hops from the root node) and connection strength (product of the connection stiffness of each node on the path) of the structural units associated with the "Type B" path are calculated in this tree. The smaller the depth and the greater the connection strength, the higher the degree of indirect association. The association degree threshold is read from the topology optimization guidance rules. If the degree of indirect association reaches the threshold, the "Type B" path may have an indirect impact on the stress of the critical node, and the path is retained. If it does not reach the threshold, it is added to the list of paths to be deleted, but its impact on the stability of the associated structural units needs to be reassessed before deletion.

[0111] Step S1466: Based on the structural processing method after deletion of non-critical connection paths whose connection path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules, formulate a deletion method for non-critical connection paths. The deletion method includes performing a batch deletion operation on such non-critical connection paths and performing a selective deletion operation on non-critical connection paths whose connection path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules.

[0112] Based on the processing method in step S1464, a batch deletion operation method is formulated for non-critical connection paths of "Type A": all "Type A" paths are added to the batch deletion list, and the deletion operation is performed sequentially according to the path ID. During deletion, all connection nodes and associated secondary structural units (such as small connectors dedicated to the path) on the path are removed at the same time, and the internal structural connection information of the model is updated. For non-critical connection paths of "Type B", a selective deletion operation method is formulated according to the filtering method in step S1465: for "Type B" paths determined to be deleted after filtering, a deletion operation similar to that of "Type A" is performed, but the associated structural units need to be handled more carefully to ensure that these units can still be connected to the main body of the model through other paths after deletion; for "Type B" paths retained after filtering, deletion is not performed for the time being, but their information is recorded for possible simplification in the future.

[0113] Step S1467: Based on the filtering method of the retained paths and the distribution of the remaining structural units after deletion, formulate the integration method of the associated structural units. The integration method includes merging the structural units associated with the deleted paths with the structural units associated with the adjacent key connection paths and adjusting the connection angle of the integrated structural units.

[0114] For associated structural units that are isolated or detached due to the deletion of non-critical connection paths (obtained from the record of the number of associated structural units with deleted paths), analyze their spatial distribution and find the critical connection paths closest to these units (calculated by spatial distance). Determine the integration method: move the connection points of the remaining structural units to nodes adjacent to the critical connection paths by modifying the vertex coordinates of the structural units; if the remaining structural units are small, they can be directly merged with structural units associated with adjacent critical connection paths, referring to the merging method for surface units in regions with gentle curvature, calculating new vertex coordinates and connection relationships. Adjust the connection angles of the integrated structural units: rotate the structural units so that the angle between them and the critical connection paths conforms to the reasonable angle range set in the topology optimization guidance rules (e.g., avoiding acute angle connections), and adjust the angle by adjusting the direction of the normal vector.

[0115] Step S147: Determine the density simplification direction based on the density characteristics of the density redundancy sub-region. The density characteristics include the number and distribution density of structural units in the density redundancy sub-region, and the density simplification direction includes the reduction ratio of structural units in the density redundancy sub-region and the rearrangement of the remaining units.

[0116] Density characteristic parameters of density-redundant sub-regions are extracted, including the total number of structural elements within the sub-region, the number of structural elements per unit volume (distribution density), the average size of the structural elements, and the material type of the structural elements. Density simplification directions are determined based on these parameters. For density-redundant sub-regions with a large number of structural elements and high distribution density, a higher reduction ratio is set (e.g., deleting a certain percentage of structural elements within the sub-region); for sub-regions with low distribution density but still a large number of elements, a lower reduction ratio is set. The specific value of the reduction ratio should refer to the density adjustment range based on material characteristics in the topology optimization guidance rules to ensure that the density of the remaining elements remains within a safe range after reduction. The remaining elements are rearranged as follows: After reduction, the spatial positions of the remaining structural elements are adjusted using optimization algorithms (e.g., particle swarm optimization, genetic algorithms) to make their distribution more uniform or arranged according to a certain pattern (e.g., along the principal stress direction) to improve structural efficiency and maintain the overall shape of the sub-region. During rearrangement, the distance between elements needs to be calculated to avoid overlap, and the connection relationships between elements need to be updated.

[0117] Step S148: Determine the unit simplification direction based on the distribution characteristics of invalid structural units. The distribution characteristics include the location and quantity of invalid structural units, and the unit simplification direction includes the batch deletion method of invalid structural units and the repair method of surrounding structures.

[0118] Analyze the distribution characteristics of invalid structural elements, including their 3D coordinate positions (determining their spatial distribution in the model, such as concentrated or dispersed distribution) and quantity (total quantity and quantity statistics for each region). For invalid structural elements that are concentrated in location and numerous, a batch deletion method is developed: use a region selection tool to select these elements and perform batch deletion, recording the ID and associated information of the deleted elements during deletion. For dispersed invalid structural elements, batch deletion can be performed after filtering by material or structural type. Repair methods for surrounding structures: After deleting invalid structural elements, voids or discontinuous areas may remain on the model surface or inside, requiring repair. Surface repair can be achieved by generating new surface elements to fill voids, with the vertices of the new surface elements taken from the vertices of the void boundaries; internal structural repair can be achieved by extending adjacent structural elements or adding small connecting components (such as reinforcing ribs) to connect discontinuous structures. The repaired structure needs to undergo geometric continuity checks to ensure there are no obvious gaps.

[0119] Step S149: Integrate the geometric simplification direction, the connection simplification direction, the density simplification direction, and the element simplification direction to form a structural simplification strategy. The structural simplification strategy specifies the execution order of each simplification direction and the associated adaptation requirements during the execution process.

[0120] The aforementioned geometric simplification directions (for regions with gentle curvature), connectivity simplification directions (for non-critical connection paths), density simplification directions (for density-redundant sub-regions), and element simplification directions (for invalid structural elements) are integrated. The execution order must consider the interrelationships between simplification directions. For example, element simplification (deleting invalid elements) is typically executed first, followed by density simplification (reducing redundant density elements), then connectivity simplification (deleting non-critical paths), and finally geometric simplification (merging surface elements and simplifying contours). This is because earlier steps may reduce the number of regions or paths that subsequent steps need to process. Adaptation requirements include: after executing an operation in one simplification direction, the results must be fed back to other simplification directions to adjust their parameters or ranges. For example, deleting non-critical connection paths may create new regions with gentle curvature or density-redundant sub-regions, requiring re-evaluation and inclusion in the corresponding simplification direction processing. The structural simplification strategy is presented in document form, including the priority of each simplification direction, execution step flowcharts, adaptation criteria, and input / output data specifications for each step.

[0121] Step S150: Perform a structural simplification operation on the intermediate frame of the topology-optimized 3D model according to the structural simplification strategy. During the structural simplification operation, the simplification progress is synchronously fed back to the topology optimization guidance rules for dynamic adaptation, so as to obtain the simplified 3D model structure and the corresponding simplification adaptation record.

[0122] Based on the established structural simplification strategy, the intermediate framework of the topology-optimized 3D model is simplified step by step. During each simplification step (such as geometric simplification and connection simplification), the simplification progress is calculated in real time (e.g., the proportion of the area already simplified to the planned simplified area, the proportion of deleted paths to the planned deleted paths, etc.), and this progress data is fed back to the topology optimization guidance rule module. Based on the feedback progress data, the topology optimization guidance rule module dynamically adjusts the parameters of subsequent simplification steps (e.g., adjusting the deletion ratio, modifying the threshold range) to adapt to changes in the model's structural characteristics during the simplification process. For example, if geometric simplification progresses too quickly, it may mean the current threshold is set too high, requiring a reduction in the threshold to retain more details; if connection simplification progresses too slowly, it may be necessary to relax the path selection criteria. Throughout the process, each step of the simplification operation, the feedback progress data, and the adjustments made to the topology optimization guidance rules are recorded, forming a simplification adaptation record. The final simplified 3D model structure should, while meeting terrain adaptation and structural load-bearing requirements, have fewer structural units, simpler connection relationships, and a smoother surface morphology.

[0123] Step S151: According to the execution order in the structure simplification strategy, firstly perform geometric simplification operation on the gently curvature region in the middle frame of the topology-optimized 3D model, and record the proportion of the area of ​​the region where the geometric simplification operation is completed to the total area of ​​the gently curvature region as the simplification progress of the first stage.

[0124] According to the execution order specified in the structural simplification strategy, the operation process corresponding to the geometric simplification direction is initiated first, that is, geometric simplification is performed on the marked areas with gentle curvature. The operation is strictly carried out according to the geometric simplification direction specified in step S145, including merging small surface unit clusters and smoothing the edge contours of surface units. During the operation, the area of ​​the geometrically simplified region is recorded in real time (e.g., by calculating the total surface area covered by the merged surface units and the simplified contour lines). At the same time, the total area of ​​the gently curvature region is obtained from the marked record. The simplification progress of the first stage is calculated as follows: First stage simplification progress = (Area of ​​the geometrically simplified region / Total area of ​​the gently curvature region) × 100%. The calculated progress value (e.g., percentage) is stored in real time.

[0125] For example, step S1511: According to the surface unit merging method in the geometric simplification direction of the structure simplification strategy, select small surface unit clusters in the gently curvature region of the topology-optimized 3D model where the number of shared edges reaches the threshold of the number of shared edges set in the topology optimization guidance rules.

[0126] Within the topology-optimized 3D model's intermediate framework, all marked regions with gentle curvature are located. For each region, based on the face element merging method in the geometric simplification direction of the structural simplification strategy, the face element parameter analysis module is invoked to recalculate the number of shared edges for all face elements within that region (ensuring consistency with the calculation method in step S1452). The latest shared edge number threshold is read from the topology optimization guidance rules (this may have been adjusted during dynamic adaptation). Small face element clusters within the region with a shared edge number greater than or equal to this threshold are selected (the determination of small face elements is still based on the face element area threshold). The selection results are output as a list of cluster IDs.

[0127] Step S1512: Perform a face unit merging operation on the small face unit clusters whose number of shared edges reaches the threshold set in the topology optimization guidance rules. Merge adjacent face units in the small face unit cluster whose number of shared edges reaches the standard set in the structure simplification strategy into a single face unit, and record the area and position of the merged face unit.

[0128] For each small face unit cluster selected in step S1511, according to the shared edge quantity standard set in the structural simplification strategy (consistent with or slightly lower than the shared edge quantity threshold, used as the execution standard), adjacent face unit pairs with a shared edge quantity meeting the standard are selected from the cluster. Following the vertex coordinate weighted average method, normal vector calculation method, and attribute inheritance rules specified in the face unit merging method, the face unit merging operation is performed to generate a new single face unit. After merging, the original face unit pairs are deleted, and the surface geometry information and face unit connection relationships of the model are updated. The area of ​​the new face unit (calculated using the new vertex coordinates) and the center position coordinates (average of the new vertex coordinates) are recorded.

[0129] Step S1513: According to the surface unit merging method in the geometric simplification direction of the structure simplification strategy, select small surface unit clusters in the gently curvature region of the topology-optimized 3D model's intermediate frame that meet the adjacent distance requirements set in the topology optimization guidance rules.

[0130] After completing the merging operation in step S1512, the remaining small surface unit clusters (those not merged or newly generated after merging) within the gently curvature region are further filtered. Based on the surface unit merging method in the geometric simplification direction of the structural simplification strategy, the spatial location analysis module is invoked to calculate the spatial distance between the center points of surface units within each small surface unit cluster. Adjacent distance requirements (thresholds) are read from the topology optimization guidance rules. Small surface unit clusters where the distance between the center points of all surface units within the cluster is less than this adjacent distance requirement are selected.

[0131] Step S1514: Perform a surface unit merging operation on the small surface unit clusters whose spatial locations meet the adjacent distance requirements set in the topology optimization guidance rules. Merge the surface units within the small surface unit cluster whose spatial distances meet the adjacent distance standards set in the structure simplification strategy into a single surface unit, and record the area and location of the merged surface unit.

[0132] For the small clusters of surface elements selected in step S1513, according to the adjacent distance standard set in the structural simplification strategy (consistent with the adjacent distance requirement), select pairs of surface elements whose spatial distance meets the standard for merging. The merging operation is similar to step S1512, but when calculating the vertex coordinates of the new surface element, vertices with closer spatial distances are assigned higher weights. After merging, the original surface elements are deleted, the model information is updated, and the area and center position coordinates of the new surface element are recorded.

[0133] Step S1515: According to the edge contour simplification method of the geometric simplification direction in the structure simplification strategy, select the adjacent surface unit pairs with the smallest included angle in the region of gentle curvature.

[0134] After merging all eligible small surface unit clusters within a gently curvature region, extract the edge contour line of that region (composed of the edges of surface units, located at the boundary of the model surface). For adjacent surface unit pairs on the aforementioned edge contour line, recalculate their included angle (using the same method as step S1451). Select all adjacent surface unit pairs with the smallest included angle values ​​(this can be set to include angle values ​​less than a dynamically determined threshold, which is calculated based on the average curvature of the current region).

[0135] Step S1516: Perform edge contour simplification operation on the selected adjacent face unit pairs with the smallest included angle, smooth the common edge of the adjacent face unit pairs along the direction of the smallest included angle, remove redundant contour points after smoothing, and record the processed edge contour parameters.

[0136] For the adjacent face element pairs with the smallest included angle selected in step S1515, smoothing is performed on the shared edges along the direction of the smallest included angle (the cutting path direction determined in step S1454) according to the edge contour simplification method in the structural simplification strategy. A smooth contour line is generated through curve fitting, and then original contour points that are too close to the smoothing curve are removed according to the redundant contour point removal method. The processed edge contour parameters are recorded, including the coordinates of the control points of the smoothing curve, the curve equation parameters (such as the order of the B-spline and the node vector), the number of contour points removed, and the length of the processed contour line.

[0137] Step S1517: Compare the surface geometric parameters of the gently curvature region before and after the geometric simplification operation, and adjust the merging boundary and simplified contour so that the surface of the processed region has no obvious protrusions or depressions.

[0138] Before the geometric simplification operation (before step S1511), calculate the surface geometric parameters of the gently curvature region, such as total area, average curvature, maximum bulge height, and maximum depression depth. Calculate the corresponding parameters for the region after the operation. Compare the two. If significant bulges (local vertex coordinates exceeding the original region's range) or depressions (local region missing) are found in the processed region, backtrack and adjust the merging boundary (e.g., splitting over-merged face units) or simplify the contour (e.g., adding new contour points at the depressions). Iterate repeatedly until the surface geometric parameters of the processed region, compared to the original region, show that the maximum depth of both bulges and depressions is less than the surface flatness threshold set in the topology optimization guidance rules.

[0139] Step S1518: Repeat the above operation for the unprocessed parts of the curvature region until the entire curvature region has been geometrically simplified.

[0140] Check if there are any parts in the gently curvature region that have not undergone merging or simplification (such as small clusters of face units missed during the initial screening, newly generated edge contours, etc.). If so, return to step S1511 and repeat the entire geometric simplification operation process from screening to adjustment for the unprocessed parts. Repeat this process until all face units and edge contours that meet the conditions in the gently curvature region have been processed.

[0141] Step S1519: Record the number of merged surface units, the number of removed contour points, and the area of ​​the processed region during the geometric simplification operation to form a geometric simplification operation record, which serves as the basis for calculating the simplification progress in the first stage.

[0142] In each sub-step (S1512, S1514, S1516) of the geometric simplification operation, the number of merged surface units (cumulative value) and the number of removed contour points (cumulative value) are recorded in real time. After the operation is completed, the total area of ​​the smooth curvature region after processing is calculated (the sum of the areas of all merged new surface units). The above data is organized into a geometric simplification operation record, where the area of ​​the processed region is used to calculate the simplification progress of the first stage (the completed area is this total area).

[0143] Step S152: Feed back the progress of the first stage simplification to the topology optimization guidance rules. Adjust the range of values ​​for the topology adjustment parameters of the terrain-sensitive areas in the topology optimization guidance rules based on whether the progress of the first stage simplification exceeds the progress threshold set in the structure simplification strategy. If the progress of the first stage simplification exceeds the progress threshold set in the structure simplification strategy, narrow the range of values ​​for subsequent adjustments of the terrain-sensitive areas.

[0144] The calculated first-stage simplification progress value is compared with the first-stage progress threshold (e.g., 70%) set in the structural simplification strategy. If the first-stage simplification progress exceeds this threshold (e.g., reaching 85%), it indicates that the geometric simplification operation is proceeding too quickly, potentially oversimplifying gently curvature areas. This may mean that the topology adjustment parameter range for terrain-sensitive areas in the topology optimization guidance rules is set too wide, resulting in too many easily simplifiable flat areas within these areas. In this case, the range of topology adjustment parameters for terrain-sensitive areas in the topology optimization guidance rules is dynamically adjusted. For example, the upper limit of the value range for the regional structure density adjustment direction is reduced (e.g., from ±15% to ±10%), or the offset range of the regional geometric adaptation direction is reduced to decrease the potential for excessive gently curvature areas. The adjustment process is recorded in the simplification adaptation record.

[0145] Step S153: Next, perform connection simplification operation on the non-critical connection paths in the intermediate frame of the topology-optimized 3D model, and record the proportion of the number of paths completed by the connection simplification operation to the total number of non-critical connection paths, as the simplification progress of the second stage.

[0146] After the first phase of geometric simplification is completed and feedback adjustments are made, the corresponding operation process for the connection simplification direction is initiated according to the execution order of the structural simplification strategy. Connection simplification operations are performed on the marked non-critical connection paths, including the non-critical connection path deletion method and the associated structural unit integration method specified in step S146. The number of non-critical connection paths that have been deleted is recorded in real time. The total number is obtained from the marking record of non-critical connection paths. The simplification progress of the second phase = (number of non-critical connection paths deleted / total number of non-critical connection paths) × 100%.

[0147] Step S154: Feed back the second-stage simplification progress to the topology optimization guidance rules. Adjust the value range of the topology reinforcement parameters carrying key nodes in the topology optimization guidance rules according to whether the second-stage simplification progress exceeds the progress threshold set in the structure simplification strategy. When the second-stage simplification progress exceeds the progress threshold set in the structure simplification strategy, expand the value range of subsequent reinforcement of key nodes.

[0148] Compare the progress of the second-stage simplification phase with the second-stage progress threshold set in the structural simplification strategy. If the progress exceeds the threshold, it indicates that too many non-critical connection paths have been deleted, which may weaken the overall connectivity of the model. The strength of the key nodes needs to be enhanced to compensate for this. In this case, adjust the range of values ​​for the topology strengthening parameters supporting key nodes in the topology optimization guidance rules, expand the upper limit of the value range in the node connection strength adjustment direction (e.g., increase the upper limit of bolt diameter increase from 3mm to 5mm), or expand the size adjustment range in the extension direction of the node-related structure.

[0149] Step S155: Then, perform density simplification on the density-redundant sub-regions in the middle frame of the topology-optimized 3D model, and record the proportion of the number of sub-regions whose density simplification operation is completed to the total number of density-redundant sub-regions, as the simplification progress of the third stage.

[0150] Perform density simplification operations to reduce and rearrange structural units in density-redundant sub-regions. Record the number of sub-regions that have been simplified and compare it with the total number of density-redundant sub-regions to calculate the simplification progress of the third stage: (number of simplified sub-regions / total number) × 100%.

[0151] Step S156: Feed back the progress of the third stage simplification to the topology optimization guidance rules. Adjust the density adjustment direction of the terrain-sensitive area in the topology optimization guidance rules according to whether the progress of the third stage simplification is lower than the progress threshold set in the structure simplification strategy. When the progress of the third stage simplification is lower than the progress threshold set in the structure simplification strategy, adjust the focus of the density adjustment direction.

[0152] If the progress of the third stage falls below the threshold, it indicates that density simplification is difficult, which may be due to an unreasonable direction of density adjustment. The focus of density adjustment in terrain-sensitive areas should be adjusted, such as changing the priority from reducing density to optimizing distribution, or vice versa.

[0153] Step S157: Finally, perform element simplification on the invalid structural elements in the intermediate frame of the topology-optimized 3D model, and record the proportion of the number of elements that have completed the element simplification operation to the total number of invalid structural elements, as the simplification progress of the fourth stage.

[0154] The execution unit simplification direction operation is performed, batch deleting invalid structural units and repairing surrounding structures. The number of invalid units deleted is recorded, and the simplification progress of the fourth stage is calculated as (number of deleted units / total number of invalid units) × 100%.

[0155] Step S158: Feed back the progress of the fourth stage simplification to the topology optimization guidance rules. Adjust the direction of the connection strength adjustment for key nodes in the topology optimization guidance rules based on whether the progress of the fourth stage simplification is lower than the progress threshold set in the structure simplification strategy. If the progress of the fourth stage simplification is lower than the progress threshold set in the structure simplification strategy, adjust the focus of the connection strength adjustment direction.

[0156] If the progress of the fourth stage is below the threshold, it indicates that the removal of invalid elements is hindered, which may be related to excessively high connection strength of critical nodes. Adjusting the focus of connection strength adjustment, such as changing from increasing strength to optimizing connection angles, can release more invalid elements.

[0157] Step S159: After completing all structural simplification operations, the simplified three-dimensional model structure is obtained. At the same time, the correspondence between the simplification progress at each stage and the dynamic adaptation of the topology optimization guidance rules is recorded to form a simplification adaptation record.

[0158] After completing all four simplification phases, output the simplified 3D model structure. Record the simplification progress data for each phase, the content of each adjustment to the topology optimization guidance rules (such as changes in parameter value ranges and directional emphasis), the time point of the adjustment, and the reason for the adjustment, forming a simplification adaptation record.

[0159] Step S160: Output the structural data and simplified adaptation record corresponding to the simplified three-dimensional model structure. The structural data corresponding to the simplified three-dimensional model structure includes the surface geometry information, internal structural connection information and material association information of the simplified model.

[0160] The simplified 3D model structure is output in a standard format (such as FBX, OBJ, or IFC) to include its structural data, including simplified surface geometry information (vertex coordinates, surface element list, normal vectors, etc.), internal structural connection information (connection node types, path list, strength parameters, etc.), and material association information (material IDs and distribution of each structural element). A simplified adaptation record (text or XML format) is also output, containing information such as progress at each stage and rule adjustment history, for reference and verification by model users (such as communication base station designers and construction teams).

[0161] In the aforementioned data collection process, for potentially privacy-sensitive data (such as the precise geographical coordinates of base stations and the layout of internal equipment), data anonymization techniques are employed. Geographical coordinates are obfuscated (e.g., offset by a certain range but maintaining relative positional relationships), and sensitive model information in the equipment layout is anonymized. Encrypted transmission and storage technologies are used, with SSL / TLS encryption applied to model data and records during transmission, and AES encryption used to encrypt files during storage, ensuring data privacy, security, and prevention of leakage.

[0162] Based on the same inventive concept, please refer to Figure 2 The diagram shows a schematic block diagram of a three-dimensional model structure simplification system 100 with topology optimization, provided in an embodiment of this application, for performing the above-described three-dimensional model structure simplification method with topology optimization. The three-dimensional model structure simplification system 100 with topology optimization may include a communication unit 110, a machine-readable storage medium 120, and a processor 130.

[0163] In this embodiment, the machine-readable storage medium 120 can also be integrated into the processor 130 and can communicate and interact with external systems through the communication unit 110. The machine-readable storage medium 120 is used to store machine-executable instructions for executing the scheme of this application, and the processor 130 is used to execute the machine-executable instructions stored in the machine-readable storage medium 120 to implement the three-dimensional model structure simplification method combined with topology optimization provided in the foregoing method embodiments.

[0164] It should be noted that, in order to simplify the description of the present invention and thus help to understand one or more embodiments of the invention, multiple features may sometimes be grouped into one embodiment, drawing or description thereof in the foregoing description of the embodiments of the present invention.

Claims

1. A method for simplifying the structure of a three-dimensional model by combining topology optimization, characterized in that, The method includes: Acquire the initial 3D model data and corresponding scene association features generated by remote sensing photogrammetry. The initial 3D model data includes the geometric information of the model surface, the connection information of the internal structure of the model, and the material association information of each component of the model. The scene association features include the terrain adaptation requirements under the remote sensing photogrammetry scene and the structural bearing requirements of the model in the subsequent application scene. Topology optimization guidance rules are constructed based on initial 3D model data with scene association features. These rules are used to associate scene association features with the topology adjustment direction of the 3D model. The construction of these rules refers to the association between surface geometry information and internal structural connection information in the initial 3D model data. Based on the topology optimization guidance rules, a topology optimization operation is performed on the initial three-dimensional model data. During the topology optimization operation, the adjustment trajectory of the internal structural connection relationship of the model is recorded synchronously to obtain the topology-optimized three-dimensional model intermediate frame and the corresponding structural adjustment trajectory information. Based on the topology-optimized 3D model intermediate frame and the corresponding structural adjustment trajectory information, a structural simplification strategy is formulated. The structural simplification strategy matches the structural distribution pattern of the topology-optimized 3D model intermediate frame and associates the key structural adjustment nodes recorded in the structural adjustment trajectory information. According to the structural simplification strategy, the structural simplification operation is performed on the intermediate frame of the topology-optimized 3D model. During the structural simplification operation, the simplification progress is synchronously fed back to the topology optimization guidance rules for dynamic adaptation, so as to obtain the simplified 3D model structure and the corresponding simplification adaptation record. Output the structural data and simplified adaptation record corresponding to the simplified 3D model structure. The structural data corresponding to the simplified 3D model structure includes the surface geometry information, internal structural connection information and material association information of the simplified model.

2. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 1, characterized in that, The topology optimization guidance rules constructed based on the initial 3D model data with scene association features include: Extract the scene association features from the initial 3D model data with scene association features, and separate the terrain association parameters corresponding to the terrain adaptation requirements and the load association parameters corresponding to the structural load requirements of the model's subsequent application scenarios. Analyze the adaptation relationship between the surface geometry information and terrain-related parameters in the initial 3D model data, identify the geometric regions in the initial 3D model data that need to be adjusted according to terrain adaptation requirements, and mark them as terrain-sensitive regions; Analyze the matching relationship between the internal structural connection information and load-bearing related parameters in the initial three-dimensional model data, identify the structural connection nodes in the initial three-dimensional model data that need to be strengthened according to the structural load-bearing requirements, and mark them as key load-bearing nodes; A mapping relationship is established between terrain-sensitive areas and topology adjustment parameters. The topology adjustment parameters include the direction of regional structure density adjustment and the direction of regional geometric shape adaptation. The establishment of the mapping relationship refers to the surface geometric information characteristics of the terrain-sensitive areas. Establish a mapping relationship between the key nodes and the topology reinforcement parameters. The topology reinforcement parameters include the node connection strength adjustment direction and the node association structure expansion direction. The establishment of the mapping relationship refers to the internal structural connection information characteristics of the key nodes. The mapping relationship between terrain-sensitive areas and topology adjustment parameters, as well as the mapping relationship between key nodes and topology reinforcement parameters, are integrated to form the basic framework of topology optimization guidance rules; Material association information from the initial 3D model data is integrated into the basic framework of topology optimization guidance rules. The values ​​of topology adjustment parameters and topology strengthening parameters are adjusted according to the structural characteristics of different materials to form topology optimization guidance rules.

3. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 1, characterized in that, The topology optimization operation is performed on the initial 3D model data according to the topology optimization guidance rules. During the topology optimization operation, the adjustment trajectory of the internal structural connection relationship of the model is recorded synchronously to obtain the intermediate frame of the topology-optimized 3D model and the corresponding structural adjustment trajectory information, including: Import the initial 3D model data into the topology optimization processing module, and locate the terrain-sensitive areas in the initial 3D model data according to the terrain-sensitive area marking in the topology optimization guidance rules; Based on the topology adjustment parameters corresponding to the terrain-sensitive areas in the topology optimization guidance rules, the structure density adjustment operation is performed on the located terrain-sensitive areas. During the adjustment process, the density change value and change order of each structural unit in the terrain-sensitive areas are recorded. The key bearing nodes in the initial 3D model data are located according to the key bearing node marking in the topology optimization guidance rules. Based on the topology strengthening parameters corresponding to the key nodes in the topology optimization guidance rules, the connection strength adjustment operation is performed on the located key nodes. During the adjustment process, the change value and order of the connection strength between the key nodes and the associated structures are recorded. During the process of adjusting the structural density and the connection strength of key load-bearing nodes in terrain-sensitive areas, the changing nodes of the internal structural connection relationship in the initial three-dimensional model data and the connection status before and after the change are recorded simultaneously to form a structural connection change sequence. By integrating density change records of terrain-sensitive areas, connection strength change records of key nodes, and structural connection change sequences, structural adjustment trajectory information is formed. After completing all topology optimization operations, a topology-optimized 3D model intermediate framework is generated. The topology-optimized 3D model intermediate framework retains the adjusted geometry of terrain-sensitive areas and the adjusted connection state of key nodes.

4. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 1, characterized in that, The structural simplification strategy formulated based on the topology-optimized 3D model intermediate frame and the corresponding structural adjustment trajectory information includes: Extract the surface geometry information from the intermediate frame of the topology-optimized 3D model, identify the regions in the surface geometry information where the curvature change value is within the smooth interval set in the topology optimization guidance rules, and mark them as smooth curvature regions. Extract the internal structural connection information from the intermediate frame of the topology-optimized 3D model, identify structural connection paths in the internal structural connection information that are not directly related to the key nodes, and mark them as non-critical connection paths. Analyze the density change records of terrain-sensitive areas in the structure adjustment trajectory information, determine the sub-regions whose values ​​after density change are within the redundancy interval set in the topology optimization guidance rules, and mark them as density redundancy sub-regions. Analyze the structural connection change sequence in the structural adjustment trajectory information, identify structural units that do not affect the overall structural connection after the change, and mark them as invalid structural units. A geometric simplification direction is determined based on the surface geometric features of the gently curvature region. The geometric simplification direction includes the surface unit merging method and the edge contour simplification method of the gently curvature region. The connection simplification direction is determined based on the connection characteristics of non-critical connection paths. The connection characteristics include the length of the connection path and the number of associated structural units. The connection simplification direction includes the deletion method of non-critical connection paths and the integration method of associated structural units. Density simplification direction is determined based on the density characteristics of the density redundancy sub-region. The density characteristics include the number and distribution density of structural units in the density redundancy sub-region. The density simplification direction includes the reduction ratio of structural units in the density redundancy sub-region and the rearrangement of the remaining units. The simplification direction of the unit is determined based on the distribution characteristics of the invalid structural units. The distribution characteristics include the location and quantity of invalid structural units, and the simplification direction includes the batch deletion method of invalid structural units and the repair method of the surrounding structure. The geometric simplification direction, connection simplification direction, density simplification direction and unit simplification direction are integrated to form a structural simplification strategy. The structural simplification strategy clarifies the execution order of each simplification direction and the correlation and adaptation requirements in the execution process.

5. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 4, characterized in that, The method of determining the geometric simplification direction based on the surface geometric features of gently curvature regions includes: Extract the surface element parameters from the surface geometry information of the gently curvature region. The surface element parameters include the area of ​​the surface element and the included angle between adjacent surface elements. The distribution of surface unit parameters in regions with gentle curvature is statistically analyzed to identify small surface unit clusters with areas smaller than the surface unit area threshold set in the topology optimization guidance rules, and adjacent surface unit groups with included angles smaller than the included angle threshold set in the topology optimization guidance rules. The spatial distribution pattern of small facet clusters is analyzed to determine the number of shared edges and spatial relationships of facets within the small facet cluster. Based on the number of shared edges and spatial relationships, the execution order of facet merging is designed. The execution order is based primarily on the number of shared edges reaching the threshold set in the topology optimization guidance rules, and secondarily on the spatial relationships meeting the adjacent distance requirements set in the topology optimization guidance rules. Analyze the angle distribution characteristics of adjacent face unit groups, determine the adjacent face unit pairs with the smallest angle, and design the cutting path direction for simplifying the edge contour based on the angle size; The face unit merging method is determined according to the execution order of face unit merging. The face unit merging method includes performing a merging operation on small face unit clusters whose number of shared edges reaches the threshold of the number of shared edges set in the topology optimization guidance rules, and performing a merging operation on small face unit clusters whose spatial location meets the adjacent distance requirements set in the topology optimization guidance rules. The edge contour simplification method is determined based on the cutting path direction of the edge contour simplification. The edge contour simplification method includes contour line smoothing along the direction of minimum included angle and the elimination of redundant contour points. By integrating the surface unit merging method and the edge contour simplification method, a geometric simplification direction corresponding to the gently curvature region is formed. By comparing the surface geometric parameters of the gently curvature region before and after merging and simplification, the merging boundary and the simplified contour are adjusted so that the surface geometry of the processed region conforms to the geometric characteristics of the original region.

6. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 4, characterized in that, The method of determining connection simplification directions based on connection characteristics of non-critical connection paths includes: Extract the connection path length and the number of associated structural units from the connection features of the non-critical connection paths, and establish a correlation table between the connection path length and the number of associated structural units. Analyze the association table and filter out non-critical connection paths whose path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules. Mark these non-critical connection paths separately. Analyze the association table and filter out non-critical connection paths whose path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules. Mark these non-critical connection paths separately. For non-critical connection paths whose path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules, analyze the distance relationship between such non-critical connection paths and surrounding critical connection paths, and design the structural processing method after deletion based on whether the distance exceeds the transition structure supplementation threshold set in the topology optimization guidance rules. For non-critical connection paths whose path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules, analyze the degree of indirect association between the structural units associated with such non-critical connection paths and the critical nodes. Based on whether the degree of indirect association reaches the degree of association threshold set in the topology optimization guidance rules, design a method for selecting retained paths. Based on the structural processing method after deletion of non-critical connection paths whose connection path length exceeds the path length threshold set in the topology optimization guidance rules and whose number of associated structural units is lower than the unit number threshold set in the topology optimization guidance rules, a deletion method for non-critical connection paths is formulated. The deletion method includes performing batch deletion operations on such non-critical connection paths and performing selective deletion operations on non-critical connection paths whose connection path length does not exceed the path length threshold set in the topology optimization guidance rules and whose number of associated structural units reaches the unit number threshold set in the topology optimization guidance rules. Based on the selection method of the retained paths and the distribution of the remaining structural units after deletion, an integration method for the associated structural units is formulated. The integration method includes merging the structural units associated with the deleted paths with the structural units associated with the adjacent key connection paths and adjusting the connection angle of the integrated structural units. The methods for deleting non-critical connection paths and integrating associated structural units are combined to form the connection simplification direction corresponding to the non-critical connection paths.

7. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 3, characterized in that, The integrated density change records of terrain-sensitive areas, connection strength change records of key nodes, and structural connection change sequences form structural adjustment trajectory information, including: The density change records of the terrain-sensitive area are marked with a time axis, and a time sequence identifier is added to each density change value according to the execution order of the topology optimization operation to form a time-series density change record; The connection strength change records of the bearing key nodes are marked with node numbers. A unique number is assigned to each bearing key node, and the connection strength change value is associated with the corresponding bearing key node number to form a node-based strength change record. The structural connection change sequence is classified by change type. The change events in the structural connection change sequence are divided into three categories: connection addition, connection deletion and connection adjustment. A type identifier is added to each type of change event to form a classified change sequence. Establish the association between time-series density change records and categorized change sequences. Determine the time overlap points between density changes and structural connection changes based on time sequence identifiers, and record the density change values ​​and corresponding change events at the time overlap points. Establish the association between node-based strength change records and categorized change sequences. Determine the node association points between the connection strength changes of the key load-bearing nodes and structural connection changes based on the number of the key load-bearing nodes. Record the connection strength change values ​​and corresponding change events at the node association points. The time-series density change records, node-based intensity change records, categorized change sequences, and their associated records with the categorized change sequences are integrated to form structural adjustment trajectory information. The structural adjustment trajectory information includes associated data in the time dimension, node dimension, and change type dimension.

8. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 2, characterized in that, The framework for integrating material association information from the initial 3D model data into topology optimization guidance rules, and adjusting the values ​​of topology adjustment parameters and topology strengthening parameters according to the structural characteristics corresponding to different materials, includes: Extract the material association information from the initial three-dimensional model data, separate the structural units corresponding to different materials, and count the number and distribution area of ​​structural units corresponding to each material. Analyze the structural characteristics of each material, including the compressive strength and deformation coefficient of the material, and determine the range of topological adjustments that the structural unit corresponding to each material can withstand. For the topology adjustment parameters corresponding to the terrain-sensitive area, the value range of the structural density adjustment direction is adjusted according to the structural characteristics of different materials in the terrain-sensitive area. The upper limit of the value range is increased in areas where the material compressive strength meets the compressive strength threshold set in the topology optimization guidance rules, and the lower limit of the value range is decreased in areas where the material deformation coefficient meets the deformation coefficient threshold set in the topology optimization guidance rules. For the topology strengthening parameters corresponding to the bearing key nodes, the value range of the connection strength adjustment direction is adjusted according to the material and structural characteristics of the structural units associated with the bearing key nodes. The upper limit of the value range corresponding to the associated structural units whose material compressive strength meets the compressive strength threshold set in the topology optimization guidance rules is increased, and the lower limit of the value range corresponding to the associated structural units whose material deformation coefficient meets the deformation coefficient threshold set in the topology optimization guidance rules is decreased. Record the adjustment range of the topology adjustment parameters and topology reinforcement parameters corresponding to each material to form a material-parameter adjustment comparison table; The material-parameter adjustment lookup table is integrated into the basic framework of the topology optimization guidance rules. Under each topology adjustment parameter and topology enhancement parameter item in the basic framework, a corresponding material adaptation value range is added to form the topology optimization guidance rules.

9. The method for simplifying the structure of a three-dimensional model by combining topology optimization according to claim 1, characterized in that, The step of performing a structural simplification operation on the intermediate frame of the topology-optimized 3D model according to the structural simplification strategy, and synchronously feeding back the simplification progress to the topology optimization guidance rules for dynamic adaptation during the structural simplification operation, includes: According to the execution order in the structural simplification strategy, firstly, geometric simplification is performed on the gently curvature region in the middle frame of the topology-optimized 3D model. The proportion of the area where the geometric simplification operation is completed to the total area of ​​the gently curvature region is recorded as the simplification progress of the first stage. The progress of the first-stage simplification is fed back to the topology optimization guidance rules. Based on whether the progress of the first-stage simplification exceeds the progress threshold set in the structure simplification strategy, the value range of the topology adjustment parameters for terrain-sensitive areas in the topology optimization guidance rules is adjusted. When the progress of the first-stage simplification exceeds the progress threshold set in the structure simplification strategy, the value range of subsequent adjustments for terrain-sensitive areas is narrowed. Next, a connection simplification operation is performed on the non-critical connection paths in the intermediate framework of the topology-optimized 3D model. The proportion of the number of paths that have completed the connection simplification operation to the total number of non-critical connection paths is recorded as the simplification progress in the second stage. The progress of the second-stage simplification is fed back to the topology optimization guidance rules. Based on whether the progress of the second-stage simplification exceeds the progress threshold set in the structural simplification strategy, the value range of the topology reinforcement parameters carrying key nodes in the topology optimization guidance rules is adjusted. When the progress of the second-stage simplification exceeds the progress threshold set in the structural simplification strategy, the value range of subsequent reinforcement of key nodes is expanded. Then, density simplification is performed on the density-redundant sub-regions in the intermediate frame of the topology-optimized 3D model. The proportion of the number of sub-regions that have completed the density simplification operation to the total number of density-redundant sub-regions is recorded as the simplification progress in the third stage. The progress of the third-stage simplification is fed back to the topology optimization guidance rules. Depending on whether the progress of the third-stage simplification is lower than the progress threshold set in the structure simplification strategy, the density adjustment direction of the terrain-sensitive area in the topology optimization guidance rules is adjusted. When the progress of the third-stage simplification is lower than the progress threshold set in the structure simplification strategy, the focus of the density adjustment direction is adjusted. Finally, perform element simplification on the invalid structural elements in the intermediate frame of the topology-optimized 3D model, and record the proportion of the number of elements that have completed the element simplification operation to the total number of invalid structural elements as the simplification progress of the fourth stage. The progress of the fourth stage simplification is fed back to the topology optimization guidance rules. Depending on whether the progress of the fourth stage simplification is lower than the progress threshold set in the structural simplification strategy, the direction of the connection strength adjustment for key nodes in the topology optimization guidance rules is adjusted. When the progress of the fourth stage simplification is lower than the progress threshold set in the structural simplification strategy, the focus of the connection strength adjustment direction is adjusted. After completing all structural simplification operations, a simplified 3D model structure is obtained. At the same time, the correspondence between the simplification progress at each stage and the dynamic adaptation of the topology optimization guidance rules is recorded to form a simplification adaptation record.

10. A 3D model structure simplification system incorporating topology optimization, characterized in that, include: processor; A machine-readable storage medium for storing machine-executable instructions of the processor; The processor is configured to execute the three-dimensional model structure simplification method incorporating topology optimization as described in any one of claims 1 to 9 by executing the machine-executable instructions.

Images