Derivative optimization and performance evaluation method for electric arc additive space cable-strut node

Abstract

The invention relates to an electric arc additive space cable-strut node derivative optimization and performance evaluation method, which comprises the steps of setting a reserved geometry and an obstacle geometry for a cable-strut node initial model, and giving an additive direction; initial conditions and additive process constraints are applied to the reserved geometry, and a derivative optimization target with structural rigidity maximization as a target is set; based on a derivative design algorithm, introducing an electric arc additive manufacturing process constraint including a printing direction and a suspension angle threshold value when a design space is constructed, and automatically generating a node topological configuration meeting the requirements of light weight and manufacturability; and carrying out additive manufacturing process performance simulation evaluation and refined mechanical bearing performance simulation evaluation. The method has the beneficial effects that a derivative design-simulation-evaluation integrated technical solution integrating manufacturing constraints is constructed; and the diversified and multi-working-condition design requirements on the curved surface modeling and the light weight of the space cable-strut node are met.

Description

Technical Field

[0001] This invention relates to the field of structural engineering technology, and more specifically, to a method for optimizing and evaluating the performance of arc additive spatial cable-stayed joints. Background Technology

[0002] Spatial cable-stayed joints, due to their requirements for aesthetics and lightweight design, are particularly suitable for manufacturing using Wafer Arc Additive Manufacturing (WAAM) technology. However, current manufacturing methods still suffer from problems such as redundant support structures, low material utilization, and inaccurate prediction of mechanical properties. Combining traditional topology optimization design methods can reduce the support structure and material consumption of spatial cable-stayed joints to some extent. However, due to the one-to-one correspondence between input and output inherent in topology optimization methods, it is impossible to generate a vast number of candidate solutions for selection, and the optimization results often fail to meet the designers' diverse aesthetic requirements. Furthermore, topology optimization results only address optimization solutions under specific working conditions, i.e., local optima, and cannot cover potential optimal solutions under multiple working conditions. These shortcomings limit designers' diverse and multi-working-condition design requirements for the curved surface styling and lightweighting of spatial cable-stayed joints.

[0003] Derivative optimization, as a novel human-machine collaborative optimization method, has demonstrated significant advantages in the field of structural engineering in recent years. This method deeply integrates deep learning and cloud computing technologies, constructing a multi-dimensional design constraint system, including boundary conditions, assembly interface positioning, manufacturing process parameters, and mechanical performance indicators. It generates a massive number of candidate solutions based on intelligent algorithms, and finally selects the optimal solution set based on a multi-objective evaluation system for engineers to make decisions. The engineering significance of derivative design lies primarily in liberating designers from repetitive tasks, achieving an exponential increase in design efficiency.

[0004] Applying derivative optimization design to the field of spatial cable-stayed joints in arc additive manufacturing can effectively solve the design challenges of diverse, multi-condition, and potential optimal solutions encountered in traditional topology optimization, overcoming problems such as redundant support structures, low material utilization, and inaccurate prediction of mechanical properties during manufacturing. However, how to construct a complete integrated technology solution that incorporates manufacturing constraints for derivative design-simulation-evaluation remains the main challenge and a problem that needs to be solved.

[0005] In summary, it is essential to study a method for the derivation optimization and performance evaluation of spatial cable-stayed joints in arc additive manufacturing, so as to realize the derivation optimization of multi-parameter schemes, simulation of printing process paths, evaluation of additive and mechanical properties, and application design of spatial cable-stayed joints under arc additive constraints. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a method for the derivation optimization and performance evaluation of spatial cable-stayed joints in arc additive manufacturing.

[0007] Firstly, a method for optimizing and evaluating the performance of arc-additive spatial cable-stayed joints is provided, including:

[0008] S1. Cable-stayed node model parameter preprocessing: For the initial model of the cable-stayed node, set the retained geometry and obstacle geometry, and give the additive direction; apply initial conditions and additive process constraints to the retained geometry, and set a derivational optimization objective with the goal of maximizing structural stiffness;

[0009] S2. Derivative Optimization Design under Additive Constraints: Based on the derivative design algorithm, when constructing the design space, the arc additive manufacturing process constraints including the printing direction and overhang angle threshold are introduced to automatically generate the node topology configuration that meets the requirements of lightweighting and manufacturability.

[0010] S3. Performance evaluation of cable-stayed joint derivative model: For the cable-stayed joint derivative design model generated in S2 under electric arc additive constraint, perform additive manufacturing process performance simulation evaluation and refined mechanical bearing performance simulation evaluation respectively.

[0011] Preferably, in S1, the original model of the cable-stayed joint uses ear plates to connect the circumferential arch, circumferential cable, and vertical strut, and connects the radial cable through a sliding cable clamp.

[0012] Preferably, S1 includes:

[0013] S11. Retention and Obstacle Geometry Division: Obtain the original model of the cable-stayed node and set the retention geometry and obstacle geometry; the retention geometry is the structural part that must be retained in the final design result, and the obstacle geometry is the spatial area where material generation is prohibited in the derivation optimization, including the component connection opening and the external space of the structure; in the 3D printing slicing software, the optimal placement position is obtained by calculating the rapid orientation model and the corresponding additive direction is given;

[0014] S12. Initial conditions and additive constraints are applied: Fixed constraints are applied to the top sliding cable clamp retaining geometry, and axial force loads are applied to the circumferential arch, circumferential cable, and vertical strut retaining geometry, the loads being determined based on the most unfavorable working condition; the additive constraints include multiple printing directions selected in the positive and negative six directions of the X, Y, and Z axes, as well as the overhang angle and minimum thickness; an "unrestricted" derivation result without additive constraints is set as a reference;

[0015] S13. Derivative optimization objective setting: Maximize the stiffness of the cable-stayed joint as the derivative optimization objective, and set the ratio of material yield strength to actual equivalent stress to 1. Submit the derivative design platform to generate the cable-stayed joint optimization model.

[0016] Preferably, S2 includes:

[0017] S21. Additive Constraint Derivative Optimization Analysis: The additive constraint-based derivative design algorithm is optimized using a comprehensive objective function, the formula of which is:

[0018]

[0019] Where F1(n) is the objective function of the space filling criterion, and F2(n) is the objective function of the non-cohesion criterion; α is the penalty factor, which controls the degree of influence of the overhang angle constraint on the derived optimization results by adjusting the value of α; G(x) is the overhang angle constraint function, which is used to measure the degree of violation of the overhang angle constraint in the design scheme; i is the number of the surface element; It is the collection of all surface units;

[0020] S22. Parameter analysis generates derivative models: Multiple cable-stayed joint derivative design models with different configurations are generated through parameter analysis; the derivative design models all exhibit hollowed-out and gridded geometric shapes in the connection area between the main pipe and the cable-stayed joint.

[0021] Preferably, S3 includes:

[0022] S31. Additive Manufacturing Performance Evaluation: The additive manufacturing path is simulated using 3D slicing software. The manufacturing process of cable-stayed node derivative design models with different configurations is simulated under specified tree support structure, suspension angle, printing layer height, infill density, and support pattern. The consumption of support materials for different configurations and their percentage of total material consumption are quantified and statistically analyzed. The support material consumption rate and economic indicators under different additive manufacturing directions are compared and evaluated.

[0023] S32. Mechanical bearing capacity assessment: Import the cable-stayed joint derivative design model into the finite element analysis software, set the material anisotropy, perform refined static performance simulation of the joint, and analyze the stress distribution, deformation response and potential failure modes of the derivative model with better additive constraint effect.

[0024] By combining additive manufacturing constraints and derived optimization methods, two significant features of the optimization results for spatial cable-stayed nodes are achieved: solution space scalability and algorithm adaptability.

[0025] Secondly, an electric arc additive spatial cable-stayed joint derivation optimization and performance evaluation system is provided for performing any of the methods described in the first aspect, including:

[0026] The preprocessing module is used to set the retained geometry and obstacle geometry for the initial model of the cable-stayed joint, and to give the additive direction; to apply initial conditions and additive process constraints to the retained geometry, and to set a derivative optimization objective with the goal of maximizing structural stiffness;

[0027] The optimized design module is used to automatically generate node topology configurations that meet the requirements of lightweighting and manufacturability by introducing arc additive manufacturing process constraints, including printing direction and overhang angle thresholds, when constructing the design space based on the derivational design algorithm.

[0028] The performance evaluation module is used to perform additive manufacturing process performance simulation evaluation and refined mechanical load-bearing performance simulation evaluation on the cable-stayed joint derivative design model generated by the optimization design module.

[0029] Thirdly, a computer storage medium is provided, wherein a computer program is stored therein; when the computer program is run on a computer, the computer causes the computer to perform any of the methods described in the first aspect.

[0030] Fourthly, an electronic device is provided, comprising:

[0031] Memory, used to store computer programs;

[0032] A processor for executing the computer program to implement the method as described in any of the first aspects.

[0033] The beneficial effects of this invention are:

[0034] 1. The electric arc additive spatial cable-stayed joint derivation optimization and performance evaluation method provided by this invention addresses the problems of redundant support structure, low material utilization and inaccurate mechanical performance prediction in existing spatial cable-stayed joints manufactured using WAAM technology and combined with traditional topology optimization methods. It constructs an integrated technical solution that integrates manufacturing constraints for derivational design, simulation and evaluation, and realizes diversified and multi-condition design requirements for the curved surface modeling and lightweighting of spatial cable-stayed joints.

[0035] 2. The method for derivation optimization and performance evaluation of arc additive spatial cable-stayed joint nodes provided by this invention is based on a derivational design algorithm. When constructing the design space, it introduces WAAM process constraints such as multiple printing directions and overhang angle thresholds to automatically generate node topologies that combine lightweight design with manufacturability. Through additive manufacturing path simulation, it quantitatively evaluates the support material consumption rate and economic indicators under different printing directions, providing a basis for process scheme selection. A finite element model considering the anisotropy of WAAM steel is established to perform refined static performance simulation of the nodes, analyzing stress distribution, deformation response, and potential failure modes. Combining manufacturing feasibility, material economy, and structural performance indicators, a multi-criteria decision model is established to achieve the selection of the optimal node design scheme and performance prediction.

[0036] 3. The arc additive spatial cable-stayed joint derivation optimization and performance evaluation method provided by this invention not only considers lightweight and manufacturing convenience in the derivation design of the cable-stayed joint, but also pays attention to the stiffness requirements of the structure; by forming multiple support paths through the complex geometric topology of the joint, stress concentration is avoided, the overall stress performance of the cable-stayed joint is significantly improved, and the maximum displacement during the load-bearing process is controlled within the allowable range of the project. Attached Figure Description

[0037] Figure 1 This is a flowchart of the method for derivation optimization and performance evaluation of spatial cable-stayed joints in electric arc additive manufacturing according to the present invention;

[0038] Figure 2 This is a schematic diagram of the original model of the cable-stayed joint;

[0039] Figure 3 This is a schematic diagram showing the division between the retained geometry and the obstacle geometry;

[0040] Figure 4 This is a schematic diagram of the additive manufacturing direction of a three-axis printer;

[0041] Figure 5 These are schematic diagrams of seven different cable-stayed joint configurations derived optimization models;

[0042] Figure 6 This is a schematic diagram showing the additive manufacturing simulation results and the percentage of supporting materials.

[0043] Figure 7a This is a schematic diagram of the nodal additive manufacturing simulation results with additive constraints in the Z+ direction;

[0044] Figure 7b This is a schematic diagram of the nodal additive manufacturing simulation results with Y-direction additive constraints;

[0045] Figure 8a This is the Mises stress contour plot of the node-derived optimization model under additive constraints in the Z+ direction;

[0046] Figure 8b It is the displacement contour plot of the node-derived optimization model under additive constraints in the Z+ direction;

[0047] Figure 9a This is the Mises stress contour plot of the node-derived optimization model under additive manufacturing constraints in the Y-direction;

[0048] Figure 9b It is the displacement contour plot of the node-derived optimization model under additive manufacturing constraints in the Y-direction. Detailed Implementation

[0049] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0050] Example 1:

[0051] To address the problems of existing technologies, Embodiment 1 of this application provides a method for optimizing and evaluating the node derivation of arc additive spatial cable-stayed rods, such as... Figure 1 As shown, it includes:

[0052] S1. Cable-stayed node model parameter preprocessing: For the initial model of the cable-stayed node, there is no need to define the design domain. Set the retained geometry and obstacle geometry, and give the additive direction. Apply initial conditions and additive process constraints to the retained geometry, and set a derivational optimization objective with the goal of maximizing structural stiffness.

[0053] Specifically, such as Figure 2 As shown, the cable-stayed truss of the roof has a complex shape and is suitable for fabrication using electric arc additive manufacturing after optimization. The original model of the cable-stayed truss uses ear plates to connect the circumferential arch, circumferential cables and vertical struts, and connects the radial cables through sliding cable clamps. All of these are axial force components.

[0054] Specifically, S1 includes:

[0055] S11. Retention and Obstacle Geometry Division: Obtain the original model of the cable-stayed node and set the retention geometry and obstacle geometry; the retention geometry is the structural part that must be retained in the final design result, and the obstacle geometry is the spatial area where material generation is prohibited in the derivation optimization, including the component connection opening and the external space of the structure.

[0056] Specifically, such as Figure 3 As shown, in the reserved geometry, the reserved length of the circumferential arch is set. The rings connecting the circumferential cables and the rings connecting the vertical struts on the ear plates adopt the original model size. The bottom of the lower half of the top radially sliding cable clamp is set with a cuboid reserved geometry to connect with the cable clamp. In the obstacle geometry, the derived optimized generated geometry is prevented from appearing outside the arch, at the connection opening of the cables and struts, that is, in spaces that will not appear in the design.

[0057] In addition, such as Figure 4 As shown, the model is initially positioned and oriented in the 3D printing slicing software Cura. The original model is imported, and the Auto Orientation plugin is used to adjust the position. This plugin can quickly orient the model to obtain the optimal position, obtain the optimal printing path position through orientation, and give the corresponding additive direction.

[0058] S12. Initial conditions and additive constraints are applied: (e.g.) Figure 2 As shown, a fixed constraint is applied to the top sliding cable clamp retaining geometry, and axial force loads are applied to the circumferential arch, circumferential cable, and vertical strut retaining geometry. The loads are determined based on the most unfavorable working condition, and the magnification factor is increased when the load is small to achieve better derivative results. The additive constraints include multiple printing directions selected in the positive and negative six directions of the X, Y, and Z axes, as well as the overhang angle and minimum thickness.

[0059] Specifically, the WAAM (Wire Arc Additive Manufacturing) process is used for printing, and metal wire is selected as the raw material. The material properties of the WAAM metal tensile specimen in the most unfavorable printing direction (i.e., perpendicular to the deposition layer direction) are adopted to improve the safety of the printed parts. The middle plane of the circumferential arch is taken as the plane of symmetry to make the derivative design result symmetrical.

[0060] like Figure 2 , Figure 4 As shown, in the additive manufacturing constraints, the X±, Y± and Z± directions are selected as the set constraints, the overhang angle is controlled at 45°, and the minimum thickness is the same as the tensile specimen thickness of the selected material properties. In addition, an "unrestricted" derivation without additive manufacturing constraints is set as a reference design result.

[0061] S13, Setting Derivative Optimization Objectives: such as... Figure 1 As shown, the goal of the derivation optimization is to maximize the stiffness of the cable-stayed joint, and the ratio of the material yield strength to the actual equivalent stress (i.e., the safety factor) is set to 1. The model is then submitted to the derivation design platform to generate the cable-stayed joint optimization model.

[0062] For example, after setting the parameters, submit the model to the Autodest Fusion 360 cloud platform for derivative optimization to obtain a high-performance, cost-effective, and aesthetically pleasing cable-stayed node optimization model.

[0063] S2. Derivative Optimization Design under Additive Constraints: Based on the derivative design algorithm, when constructing the design space, arc additive manufacturing process constraints including printing direction and overhang angle thresholds are introduced to automatically generate node topology configurations that meet the requirements of lightweighting and manufacturability.

[0064] S2 includes:

[0065] S21, Additive Constraint Derivative Optimization Analysis: such as Figure 1 As shown, the additive manufacturing constraint-based derivational design algorithm uses a comprehensive objective function for optimization, and considers the overhang angle constraint during the additive manufacturing process; the comprehensive objective function F AM The formula for (n) is:

[0066]

[0067] In the formula, F1(n) is the objective function of the space filling criterion, and F2(n) is the objective function of the non-cohesion criterion; α is the penalty factor, which can control the degree of influence of the overhang angle constraint on the derived optimization results by adjusting the value of α; G(x) is the overhang angle constraint function, which is used to measure the degree of violation of the overhang angle constraint in the design scheme; i is the number of the surface element. It is the collection of all surface units.

[0068] To effectively explore the design space, a space-filling criterion is introduced in the derivation optimization to ensure that the generated design schemes are uniformly distributed within the space; the objective function F1(n) of the space-filling criterion in equation (1) is:

[0069]

[0070] In the formula, X p and X q These are the design schemes corresponding to the design values ​​p and q, respectively; D(X) p ,X q ) is the Euclidean distance between the design values ​​p and q; n is the total number of design variables in a single design scheme;

[0071] To avoid the design schemes being too concentrated at the spatial boundary, a non-cohesion criterion needs to be added to ensure a reasonable distribution of the design schemes; the objective function F2(n) of the non-cohesion criterion is:

[0072]

[0073] In the formula, y p and y q They are X p and X q Discretized representation; κ(y p ,y q F2(n) is the number of shared intervals between the design values ​​p and q; by adjusting the control parameter Ω, the weights of F2(n) are adjusted to obtain a complete and uniform set of feasible solutions.

[0074] In a given design space χ, the set of derived optimization results x consists of m feasible design schemes. m for:

[0075] x m ={x(m,k)}∈χ,k=1,2,...,n (4)

[0076] In the formula, m is the number of the feasible design scheme, used to distinguish different derived optimization results; k is the design variable number; x(m,k) is the value of the k-th design variable in the m-th feasible design scheme, used to describe the parameters of the design scheme in terms of geometric shape or structural features;

[0077] When considering overhang angle constraints, the angle of material accumulation in printing cannot exceed the critical value θ allowed by the printing equipment. cr Otherwise, an additional support structure is required, which increases manufacturing complexity and cost; the overhang angle constraint function G(x) is:

[0078]

[0079] In the formula, θ i θ is the overhang angle of the i-th surface element; cr The critical overhang angle; for any structural surface element, the normal vector n i When the direction perpendicular to the printing substrate is z, the overhang angle θ of the i-th surface unit is... i for:

[0080]

[0081] S22. Parameter analysis generates derivative models: Multiple cable-stayed joint derivative design models with different configurations are generated through parameter analysis; the derivative design models all exhibit hollowed-out and gridded geometric shapes in the connection area between the main pipe and the cable-stayed joint.

[0082] Specifically, in the S22 parameter analysis to generate derivative models, seven different configurations of cable-stayed joint derivative design models are generated through parameter analysis of derivative design; among them, X±, Y±, and Z± represent the main printing directions in the additive manufacturing process, and "unrestricted" is the derivative design result without manufacturing constraints.

[0083] Under the constraints of derivative design and additive manufacturing, the cable-rod node derivative design model exhibits obvious geometric topology optimization characteristics; all derivative design models show complex geometric shapes with hollowing and meshing in the connection area between the main pipe and the cable.

[0084] S3. Performance evaluation of cable-stayed joint derivative model: For the cable-stayed joint derivative design model generated in S2 under electric arc additive constraint, perform additive manufacturing process performance simulation evaluation and refined mechanical bearing performance simulation evaluation respectively.

[0085] Example 2:

[0086] Based on Example 1, Example 2 of this application provides a more specific method for optimizing and evaluating the performance of arc additive spatial cable-stayed joints, including:

[0087] S1. Cable-stayed node model parameter preprocessing: For the initial model of the cable-stayed node, set the retained geometry and obstacle geometry, and give the additive direction; apply initial conditions and additive process constraints to the retained geometry, and set a derivational optimization objective with the goal of maximizing structural stiffness.

[0088] S2. Derivative Optimization Design under Additive Constraints: Based on the derivative design algorithm, additive manufacturing process constraints including printing direction and overhang angle thresholds are introduced when constructing the design space to automatically generate node topology configurations that meet the requirements of lightweighting and manufacturability.

[0089] S3. Performance evaluation of the cable-stayed node derivative model: For the cable-stayed node derivative design model generated in S2 under additive constraints, perform additive manufacturing process performance simulation evaluation and refined mechanical bearing performance simulation evaluation respectively.

[0090] S3 includes:

[0091] S31. Additive Manufacturing Performance Evaluation: The additive manufacturing path is simulated using 3D slicing software. The manufacturing process of cable-stayed node derivative design models with different configurations is simulated under specified tree-shaped support structure, suspension angle, printing layer height, infill density, and support pattern. The consumption of support materials for different configurations and their percentage of total material consumption are quantified and statistically analyzed. The support material consumption rate and economic indicators under different additive manufacturing directions are compared and evaluated.

[0092] Specifically, such as Figure 6 As shown in Figure 7, additive manufacturing simulations of different configuration-derived optimization models were performed using the 3D slicing software Cura. The additive manufacturing path of the WAAM three-axis printer was adopted, a tree-shaped support structure was set, and the overhang angle, printing layer height, infill density, and support pattern were set. The percentage of support material to total material corresponding to different configurations was plotted, and the support material consumption rate and economic indicators under different additive manufacturing directions were compared and evaluated to provide a basis for process scheme selection.

[0093] To address the printing difficulties caused by excessive overhang angles during additive manufacturing, in practical engineering applications, when dealing with large-sized or structurally complex models, the additive manufacturing field still tends to use the method of adding support structures to ensure the stability and forming quality of the three-axis printing process. The support constraints that may arise during the three-axis printing process are fully considered in the design stage, and the use of support structures is actively reduced or avoided through design optimization, thereby reducing printing costs and post-processing difficulties and improving the overall efficiency of additive manufacturing.

[0094] S32. Mechanical bearing capacity assessment: Import the cable-stayed joint derivative design model into the finite element analysis software, set the material anisotropy, perform refined static performance simulation of the joint, and analyze the stress distribution, deformation response and potential failure modes of the derivative model with better additive constraint effect.

[0095] Specifically, as shown in Figures 8 and 9, a finite element model considering the anisotropy of WAAM steel is established, and the static performance of the nodes is simulated in detail. The stress distribution, deformation response and potential failure modes of the derivative model with better additive constraint effect are analyzed, and the mechanical bearing performance is evaluated.

[0096] The derived optimized node model with good additive constraint effect obtained from S22 was imported into the finite element software ABAQUS for static loading performance simulation analysis. The specific process is as follows: the derived optimization results were exported from the Autodest Fusion 360 cloud platform in mm unit format as Step format files, imported into the mesh generation software Hyper Mesh to mesh the derived optimized model, using tetrahedral mesh elements, setting the mesh size, and then exported as an inp file format recognizable by ABAQUS software. Finally, mechanical performance simulation was performed in the ABAQUS finite element software.

[0097] Combining additive manufacturing constraints and derived optimization methods, two significant characteristics of the spatial cable-stayed joint node optimization results can be achieved: 1) Solution space extensibility. While minimizing the objective function, a non-dominated solution set satisfying the constraints can be generated, rather than a single optimal solution; this characteristic provides a multi-dimensional basis for performance trade-offs in design decisions. 2) Algorithm adaptability. Through the dynamic coupling of stochastic algorithms and reinforcement learning, the algorithm can autonomously explore potential optimal topologies within the design domain, breaking through the local optima limitations of traditional gradient optimization methods.

[0098] This application also provides a method for the derivation optimization and performance evaluation of spatial cable-stayed joints in arc additive manufacturing, and its practical application in the derivation optimization of multi-parameter schemes, simulation of printing process paths, and evaluation of additive and mechanical properties of spatial cable-stayed steel joints under arc additive manufacturing constraints.

[0099] Figure 2 The original model of the cable-stayed joint is shown below; Figure 3 The lighter-colored areas represent retained geometry, while the darker-colored areas represent obstacle geometry; for example... Figure 4 As shown, the optimal placement position is the additive manufacturing direction with the cable clamp as the printing base; the filament is ER316L stainless steel filament, and a 4mm thick tensile specimen is selected. The performance of WAAM material in the most unfavorable printing direction is shown in Table 1; in the additive manufacturing constraints, the minimum thickness is 4mm, which corresponds to the same thickness as the tensile specimen.

[0100] Table 1. Properties of WAAM 316L stainless steel in the most unfavorable printing direction.

[0101]

[0102] Table 2 shows the specific parameter data for seven different additive manufacturing orientation configurations;

[0103] Table 2. Parameter data for 7 different configurations

[0104]

[0105] like Figure 5 As shown, for the X+ derivative model, a triangular structure is formed between the circumferential arch and the cable clamp, which improves the internal stability of the node and the overall resistance to deformation, and the shape has a clear "growth" feel. For the Y± derivative model, a filling design is formed at the connection ring of the circumferential arch, which significantly improves the local load-bearing capacity and resistance to local instability of the node. For the Z± derivative model, the connection between the circumferential arch and the circumferential cable presents a natural transition surface, reducing unnecessary reinforcing ribs, which further reduces the total weight of the node, while maintaining good stress continuity. The connection between the vertical struts and cable clamps in all derivative design models presents a stable triangular structure, which can further improve the overall stability of the structure.

[0106] like Figure 6 Figure 7 shows the additive manufacturing simulation verification and evaluation for six different configurations; the overhang angle was set to 45°, the printing layer height was 2mm, the infill density was 20%, and the support pattern was a grid; the additive manufacturing simulation results and the percentage of support material are as follows. Figure 5 As shown, the light color represents the support material, and the dark color represents the model material. The percentage on the vertical axis represents the ratio of support material to total material; the area with a relatively small proportion of support material is along the Z+ direction (…). Figure 7a ) and Y-direction ( Figure 7b The derived optimization results are shown in Table 3, which shows the material mass consumed under supported and unsupported conditions in different additive directions.

[0107] Table 3. Material consumption (with and without support) under different additive manufacturing directions (unit: kg)

[0108]

[0109] As shown in Figures 8 and 9, additive constraint derivative models in the Z+ and Y- directions, which exhibit better additive constraint effects, were selected to obtain Mises stress and displacement contour maps. For the Z+ direction additive constraint derivative model, the maximum Mises stress was 195 MPa. Figure 8a The yield strength is significantly lower than that of WAAM 316L stainless steel (262 MPa), and the maximum displacement is 0.781 mm. Figure 8b The displacement decreases gradually along the length of the member, and the structure is in an elastic working state. For the additive constraint derived model in the Y-direction, stress concentration occurs at the connection between the cable clamp and the adjacent member, with a peak stress of approximately 479.3 MPa. Figure 9aThe average stress was approximately 152.9 MPa, mainly due to an insufficiently smooth geometric transition and a localized undersized rod diameter. Further optimization of the transition fillets and cross-sectional parameters is needed.

[0110] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0111] Example 3:

[0112] Based on Example 2, Example 3 of this application provides an arc additive spatial cable-stayed joint derivation optimization and performance evaluation system, including:

[0113] The preprocessing module is used to set the retained geometry and obstacle geometry for the initial model of the cable-stayed joint, and to give the additive direction; to apply initial conditions and additive process constraints to the retained geometry, and to set a derivative optimization objective with the goal of maximizing structural stiffness;

[0114] The optimized design module is used to automatically generate node topology configurations that meet the requirements of lightweighting and manufacturability by introducing arc additive manufacturing process constraints, including printing direction and overhang angle thresholds, when constructing the design space based on the derivational design algorithm.

[0115] The performance evaluation module is used to perform additive manufacturing process performance simulation evaluation and refined mechanical load-bearing performance simulation evaluation on the cable-stayed joint derivative design model generated by the optimization design module.

[0116] Specifically, the system provided in this embodiment is the same as the system provided in embodiment 2. Therefore, the parts in this embodiment that are the same as or similar to those in embodiment 2 can be referred to each other and will not be described again in this application.

[0117] In summary, the method for derivation optimization and performance evaluation of spatial cable-stayed joints provided by this invention, based on a derivational design algorithm, introduces WAAM process constraints such as multiple printing directions and overhang angle thresholds when constructing the design space, automatically generating a joint topology configuration that combines lightweighting and manufacturability. Through additive manufacturing path simulation, it quantitatively evaluates the support material consumption rate and economic indicators under different printing directions, providing a basis for process scheme selection. A finite element model considering the anisotropy of WAAM steel is established to perform refined static performance simulation of the joints, analyzing stress distribution, deformation response, and potential failure modes. Combining manufacturing feasibility, material economy, and structural performance indicators, a multi-criteria decision model is established to achieve the selection of the optimal joint design scheme and performance prediction. A set of integrated derivational design-simulation-evaluation technical solutions integrating manufacturing constraints is constructed. Furthermore, practical verification has shown that the method of this invention is effective.

Claims

1. A method for optimizing and evaluating the performance of nodes in arc additive spatial cable-stayed structures, characterized in that, include: S1. Cable-stayed node model parameter preprocessing: For the initial model of the cable-stayed node, set the retained geometry and obstacle geometry, and give the additive direction; Initial conditions and additive manufacturing process constraints are applied to the retained geometry, and a derivative optimization objective is set to maximize the structural stiffness. S2. Derivative Optimization Design under Additive Constraints: Based on the derivative design algorithm, when constructing the design space, the arc additive manufacturing process constraints including the printing direction and overhang angle threshold are introduced to automatically generate the node topology configuration that meets the requirements of lightweighting and manufacturability. S3. Performance evaluation of cable-stayed joint derivative model: For the cable-stayed joint derivative design model generated in S2 under electric arc additive constraint, perform additive manufacturing process performance simulation evaluation and refined mechanical bearing performance simulation evaluation respectively.

2. The method for optimizing and evaluating the node derivation of arc additive spatial cable-stayed rods according to claim 1, characterized in that, In S1, the original model of the cable-stayed joint uses ear plates to connect the circumferential arch, circumferential cable, and vertical strut, and connects the radial cable through a sliding cable clamp.

3. The method for optimizing and evaluating the node derivation of arc additive spatial cable-stayed rods according to claim 2, characterized in that, S1 includes: S11. Preservation and Obstacle Geometry Division: Obtain the original model of the cable node and set the preservation geometry and obstacle geometry; The retained geometry refers to the structural parts that must be retained in the final design result, and the obstacle geometry refers to the spatial regions where material generation is prohibited in the derivation optimization, including component connection openings and external space of the structure. In 3D printing slicing software, the optimal placement position is obtained by calculating the rapid orientation model and the corresponding additive direction is given; S12. Initial conditions and additive constraints are applied: Fixed constraints are applied to the top sliding cable clamp retaining geometry, and axial force loads are applied to the circumferential arch, circumferential cable, and vertical strut retaining geometry, the loads being determined based on the most unfavorable working condition; the additive constraints include multiple printing directions selected in the positive and negative six directions of the X, Y, and Z axes, as well as the overhang angle and minimum thickness; an "unrestricted" derived generation result without additive constraints is set as a reference; S13. Derivative optimization objective setting: Maximize the stiffness of the cable-stayed joint as the derivative optimization objective, and set the ratio of material yield strength to actual equivalent stress to 1. Submit the derivative design platform to generate the cable-stayed joint optimization model.

4. The method for derivation optimization and performance evaluation of arc additive spatial cable-stayed rod nodes according to claim 3, characterized in that, S2 include: S21. Additive Constraint Derivative Optimization Analysis: The additive constraint-based derivative design algorithm is optimized using a comprehensive objective function, the formula of which is: Where F1(n) is the objective function of the space filling criterion, and F2(n) is the objective function of the non-cohesion criterion; α is the penalty factor, which controls the degree of influence of the overhang angle constraint on the derived optimization results by adjusting the value of α; G(x) is the overhang angle constraint function, which is used to measure the degree of violation of the overhang angle constraint in the design scheme; i is the number of the surface element; It is the collection of all surface units; S22. Parameter analysis generates derivative models: Multiple cable-stayed joint derivative design models with different configurations are generated through parameter analysis; the derivative design models all exhibit hollowed-out and gridded geometric shapes in the connection area between the main pipe and the cable-stayed joint.

5. The method for optimizing and evaluating the node derivation of arc additive spatial cable-stayed rods according to claim 4, characterized in that, S3 includes: S31. Additive Manufacturing Performance Evaluation: The additive manufacturing path is simulated using 3D slicing software. The manufacturing process of cable-stayed node derivative design models with different configurations is simulated under specified tree support structure, suspension angle, printing layer height, infill density, and support pattern. The consumption of support materials for different configurations and their percentage of total material consumption are quantified and statistically analyzed. The support material consumption rate and economic indicators under different additive manufacturing directions are compared and evaluated. S32. Mechanical bearing capacity assessment: Import the cable-stayed joint derivative design model into the finite element analysis software, set the material anisotropy, perform refined static performance simulation of the joint, and analyze the stress distribution, deformation response and potential failure modes of the derivative model with better additive constraint effect. By combining additive manufacturing constraints and derived optimization methods, two significant features of the optimization results for spatial cable-stayed nodes are achieved: solution space scalability and algorithm adaptability.

6. An electric arc additive spatial cable-stayed rod node derivation optimization and performance evaluation system, characterized in that, For performing the method as described in any one of claims 1 to 5, comprising: The preprocessing module is used to set the retained geometry and obstacle geometry for the initial model of the cable-stayed joint, and to give the additive direction; to apply initial conditions and additive process constraints to the retained geometry, and to set a derivative optimization objective with the goal of maximizing structural stiffness; The optimized design module is used to automatically generate node topology configurations that meet the requirements of lightweighting and manufacturability by introducing arc additive manufacturing process constraints, including printing direction and overhang angle thresholds, when constructing the design space based on the derivational design algorithm. The performance evaluation module is used to perform additive manufacturing process performance simulation evaluation and refined mechanical load-bearing performance simulation evaluation on the cable-stayed joint derivative design model generated by the optimization design module.

7. A computer storage medium, characterized in that, The computer storage medium stores a computer program; when the computer program is run on the computer, it causes the computer to perform the method described in any one of claims 1 to 5.

8. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the method as described in any one of claims 1 to 5.

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