Method, medium and device for generating structural force transmission frame

Abstract

The embodiment of the invention discloses a method, medium and equipment for generating a structural force transmission framework, and the method comprises the steps: carrying out the trace tracking of each discrete point of a first structural force transmission framework in a principal stress field by taking the discrete point as a starting point and taking an orthogonal direction corresponding to the discrete point as a first tracking direction, and if the tracking enters an abnormal region, carrying out the tracking; and if the main stress extreme point direction in the abnormal region is the first tracking direction, the main stress extreme point direction in the abnormal region is taken as a second tracking direction, trace tracking is ended until the main stress extreme point is reached, candidate filial generation main stress traces are obtained, and a final target structure force transmission frame is generated according to the obtained multiple candidate filial generation main stress traces and the first structure force transmission frame. According to the method, mechanical indexes are taken as guidance, the capturing capability of the structural force transmission frame on key stress characteristics is effectively enhanced, the defect that traces in a stress mutation region are easy to deviate or interrupt in a traditional method is overcome, and the generation effectiveness of the structural force transmission frame can be improved.

Description

Technical Field

[0001] This invention relates to the field of mechanical structural analysis technology, and in particular to a method, medium, and device for generating a structural force transmission frame. Background Technology

[0002] In the field of structural topology and shape optimization, "first determining the structural force transmission frame and then refining the component dimensions" has become the mainstream paradigm for achieving high-performance and lightweight designs. Among them, the frame generation method based on finite element principal stress trajectories is widely used due to its clear physical concepts and simple algorithm implementation. For example, by selecting new starting points on existing trajectories according to pure geometric rules such as equal arc length, isoparametric coordinates, or geometric arch points, iterative generation of child trajectories is generated, ultimately forming a force transmission network covering the design domain.

[0003] However, the aforementioned "geometry-driven" trace refinement strategy is essentially detached from the guidance of mechanical indicators and constitutes blind sampling. Existing "geometry-driven" principal stress trace generation methods lack mechanical significance criteria and cannot guarantee the capture of key force flow channels, resulting in low effectiveness in generating structural force transmission frames.

[0004] Therefore, the structural force transmission frame generated by the above principal stress trace generation method has the problem of low effectiveness. Summary of the Invention

[0005] Based on this, it is necessary to propose a method, medium, and device for generating structural force transmission frames to address the above-mentioned problems, aiming to solve the problem of low effectiveness of the generated structural force transmission frames.

[0006] In a first aspect, embodiments of this application provide a method for generating a structural force-transmitting frame, the method comprising: Obtain the first structural force transmission frame of the target force-bearing object; The first structural force transmission frame is discretized to obtain multiple discrete points; For each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction, trace tracing is performed in the principal stress field corresponding to the target force-bearing object. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction. The trace tracing ends when the principal stress extreme point is reached, and candidate offspring principal stress traces are obtained. If the tracking does not enter an abnormal region, the trace tracing ends when the boundary of the principal stress field is reached, and candidate offspring principal stress traces are obtained. Wherein, the orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point, the principal stress direction of the trace is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame, the first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign, the first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. Based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame, the final target structural force transmission frame of the target force-bearing object is generated.

[0007] In some embodiments, generating the final target structural force transmission frame of the target stressed object based on the acquired multiple candidate progeny principal stress trajectories and the first structural force transmission frame includes: generating a second structural force transmission frame of the target stressed object based on the acquired multiple candidate progeny principal stress trajectories and the first structural force transmission frame; if the generation of the second structural force transmission frame satisfies the iterative convergence condition, determining the final target structural force transmission frame of the target stressed object based on the second structural force transmission frame; if the generation of the second structural force transmission frame does not satisfy the iterative convergence condition, using the second structural force transmission frame as a new first structural force transmission frame, returning to the step of discretizing the first structural force transmission frame to obtain multiple discrete points.

[0008] In some embodiments, generating the second structural force transmission frame of the target force-bearing object based on the acquired multiple candidate progenitor principal stress trajectories and the first structural force transmission frame includes: modifying the acquired multiple candidate progenitor principal stress trajectories to obtain multiple first progenitor principal stress trajectories; deduplicating the multiple first progenitor principal stress trajectories to obtain at least one deduplicated second progenitor principal stress trajectories; obtaining the average strain energy density corresponding to each second progenitor principal stress trajectories in the at least one second progenitor principal stress trajectories; wherein the average strain energy density characterizes the average energy stored per unit length along the path traversed by the corresponding second progenitor principal stress trajectories; obtaining the third progenitor principal stress trajectories among the at least one second progenitor principal stress trajectories based on the average strain energy density corresponding to each second progenitor principal stress trajectories; wherein the third progenitor principal stress trajectories are the second progenitor principal stress trajectories corresponding to the maximum value of the average strain energy densities among the at least one second progenitor principal stress trajectories; and adding the third progenitor principal stress trajectories to the first structural force transmission frame to generate the second structural force transmission frame of the target force-bearing object.

[0009] In some embodiments, determining the final target structural force transmission frame of the target force-bearing object based on the second structural force transmission frame includes: replacing the curve segments between all intersections in the second structural force transmission frame with straight line segments to form the final target structural force transmission frame of the target force-bearing object.

[0010] In some embodiments, the above-described correction process for the multiple candidate progenitor principal stress trajectories to obtain multiple first progenitor principal stress trajectories includes: for a first candidate trajectory among the multiple candidate progenitor principal stress trajectories, if the endpoint of the first candidate trajectory is located on a free boundary of the target stressed object that is not subject to external forces, then the first intersection point of the first candidate trajectory and the second candidate trajectory is obtained, a second intersection point is determined from the first intersection point, and the trajectory corresponding to the endpoint of the first candidate trajectory from the second intersection point is removed to obtain the corrected first progenitor principal stress trajectories; if the endpoint of the first candidate trajectory... If the target object is not located on a free boundary free from external forces, the original first candidate trace is retained. The first candidate trace is any one of the multiple candidate principal stress traces; the free boundary is a boundary segment with zero surface force; the second candidate trace is any candidate principal stress trace other than the first candidate trace; the second intersection point is the intersection point closest to the free boundary among the first intersection points; the multiple first principal stress traces include the corrected first principal stress trace and the retained original first candidate trace.

[0011] In some embodiments, the above-described deduplication process of the plurality of first-generation principal stress trajectories to obtain at least one deduplicated second-generation principal stress trajectory includes: if there is a duplicate principal stress trajectory among the plurality of first-generation principal stress trajectories, then the duplicate principal stress trajectory is removed from the plurality of first-generation principal stress trajectories to obtain at least one deduplicated second-generation principal stress trajectory; wherein, the duplicate principal stress trajectory is the first-generation principal stress trajectory that is duplicated by the parent principal stress trajectory in the first structural force transmission frame among the plurality of first-generation principal stress trajectories.

[0012] In some embodiments, the above-mentioned method for obtaining the first structural force transmission frame of the target force-bearing object includes: constructing a finite element model of the target force-bearing object, defining a base structure corresponding to the target force-bearing object on the finite element model; performing finite element analysis on the base structure under the same load conditions as the target force-bearing object to obtain the first principal stress and the second principal stress at each Gaussian integration point within the base structure; obtaining the principal stress direction field corresponding to the target force-bearing object through bilinear interpolation based on the first principal stress and the second principal stress at each Gaussian integration point, and the direction vectors corresponding to the first principal stress and the second principal stress at each Gaussian integration point; and for each load application point and constraint application point in the principal stress direction field, performing trace tracing in the principal stress direction field with the application point as the starting point to generate the first structural force transmission frame of the target force-bearing object.

[0013] In some embodiments, the above-described method of tracing traces in the principal stress direction field for each load application point and constraint application point in the principal stress direction field, starting from the application point, to generate the first structural force transmission frame of the target force-bearing object, includes: for each load application point and constraint application point in the principal stress direction field, starting from the application point, tracing traces in the principal stress direction field using a step-by-step method to generate multiple parent principal stress traces; setting corresponding priorities for each of the multiple parent principal stress traces; and, if a target principal stress trace set exists among the multiple parent principal stress traces, if the multiple parent principal stress traces included in the target principal stress trace set have different priorities, then... The parent principal stress trajectories with non-highest priority in the target principal stress trajectories set are removed from the multiple parent principal stress trajectories to obtain corrected multiple parent principal stress trajectories. If the multiple parent principal stress trajectories included in the target principal stress trajectories set have the same priority, the multiple parent principal stress trajectories included in the target principal stress trajectories set are merged to obtain merged principal stress trajectories. The multiple parent principal stress trajectories included in the target principal stress trajectories set are then replaced with the merged principal stress trajectories to obtain corrected multiple parent principal stress trajectories. The multiple parent principal stress trajectories included in the target principal stress trajectories set are repeated. Based on the corrected multiple parent principal stress trajectories, the first structural force transmission frame of the target stress-bearing object is generated.

[0014] Secondly, embodiments of this application provide an apparatus for generating a structural force-transmitting frame, the apparatus comprising: The acquisition module is used to acquire the first structural force transmission frame of the target force-bearing object; The frame discretization module is used to discretize the first structural force transmission frame to obtain multiple discrete points; The trace tracing module is used to trace each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracing direction, in the principal stress field corresponding to the target force-bearing object. If the tracing enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracing direction, and the tracing ends when the principal stress extreme point is reached, obtaining a candidate offspring principal stress trace. If the tracing does not enter the abnormal region, the tracing ends when the boundary of the principal stress field is reached, obtaining a candidate offspring principal stress trace. The orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point. The principal stress direction is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame. The first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign. The first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. The framework generation module is used to generate the final target structural force transmission frame of the target force-bearing object based on the acquired multiple candidate offspring principal stress trajectories and the first structural force transmission frame.

[0015] Thirdly, embodiments of this application provide a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the following steps: Obtain the first structural force transmission frame of the target force-bearing object; The first structural force transmission frame is discretized to obtain multiple discrete points; For each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction, trace tracing is performed in the principal stress field corresponding to the target force-bearing object. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction. The trace tracing ends when the principal stress extreme point is reached, and candidate offspring principal stress traces are obtained. If the tracking does not enter an abnormal region, the trace tracing ends when the boundary of the principal stress field is reached, and candidate offspring principal stress traces are obtained. Wherein, the orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point, the principal stress direction of the trace is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame, the first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign, the first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. Based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame, the final target structural force transmission frame of the target force-bearing object is generated.

[0016] Fourthly, embodiments of this application provide a computer device, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the following steps: Obtain the first structural force transmission frame of the target force-bearing object; The first structural force transmission frame is discretized to obtain multiple discrete points; For each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction, trace tracing is performed in the principal stress field corresponding to the target force-bearing object. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction. The trace tracing ends when the principal stress extreme point is reached, and candidate offspring principal stress traces are obtained. If the tracking does not enter an abnormal region, the trace tracing ends when the boundary of the principal stress field is reached, and candidate offspring principal stress traces are obtained. Wherein, the orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point, the principal stress direction of the trace is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame, the first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign, the first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. Based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame, the final target structural force transmission frame of the target force-bearing object is generated.

[0017] The method, apparatus, medium, and device for generating a structural force transmission frame according to embodiments of this application discretize a first structural force transmission frame to obtain multiple discrete points. For each discrete point, a trace is traced in the principal stress field corresponding to the target force-bearing object, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction. The trace tracking ends when the principal stress extreme point is reached, and candidate offspring principal stress traces are obtained. If the tracking does not enter an abnormal region, the trace tracking ends when the boundary of the principal stress field is reached, and candidate offspring principal stress traces are obtained. Based on the obtained multiple candidate offspring principal stress traces and the first structural force transmission frame, the final target structural force transmission frame of the target force-bearing object is generated. Thus, once the trace is determined to enter a stress concentration region where the first and second principal stresses have the same sign, the stepping strategy is immediately switched to "actively climbing along the maximum principal stress gradient," and forced to terminate at the extreme point where the gradient returns to zero. This precisely pulls the trace, which would otherwise easily slip or be interrupted due to high gradient turning, towards the abrupt change hotspot and terminates it at the peak point, achieving an active connection between the principal stress trace and the stress concentration region. This allows the structural force transmission frame to automatically embed key high-stress features, significantly improving the completeness and path continuity of capturing stress abrupt change signals. Therefore, this method, guided by mechanical indicators, effectively enhances the structural force transmission frame's ability to capture key stress features, overcomes the shortcomings of traditional methods where traces are easily deviated or interrupted in stress abrupt change regions, and improves the effectiveness of generating structural force transmission frames. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] in: Figure 1 A flowchart illustrating the method for generating a structural force-transmitting frame provided in an embodiment of this application; Figure 2 This is a schematic diagram of an L-shaped beam example provided in the embodiments of this application; Figure 3(a) is a schematic diagram of the first principal stress direction field provided in the embodiment of this application; Figure 3(b) is a schematic diagram of the second principal stress direction field provided in the embodiment of this application; Figure 4 A schematic diagram of similar or overlapping traces for the L-shaped beam example provided in the embodiments of this application; Figure 5A schematic diagram of the initial force transmission frame for the L-shaped beam example provided in this application embodiment; Figure 6 A schematic diagram of candidate offspring traces for the L-shaped beam example provided in this application embodiment; Figure 7 A schematic diagram of the strain energy density field for an L-shaped beam example provided in this application embodiment; Figure 8 A schematic diagram of the S-region attraction criterion for the L-shaped beam example provided in this application embodiment; Figure 9 This is a schematic diagram of the iterative refinement of the L-shaped beam calculation example provided in the embodiments of this application; Figure 10 A schematic diagram of the target structural force transmission frame for the L-shaped beam example provided in this application embodiment; Figure 11 A structural block diagram of the device for generating a structural force transmission frame provided in an embodiment of this application; Figure 12 This is a structural block diagram of a computer device in one embodiment. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This application provides a method for generating a structural force-transfer frame. This method can be applied to and executed by a computer device. The computer device can be a server, or an electronic product with computing capabilities such as a computer, tablet, or mobile phone.

[0022] refer to Figure 1 , Figure 1 This is a flowchart illustrating the method for generating a structural force-transmitting frame provided in an embodiment of this application. Specifically, it includes the following steps S1-S4: Step S1: Obtain the first structural force transmission frame of the target force-bearing object.

[0023] The target stress object mentioned above is the research object of the structural force transmission frame to be generated. For example, it can be any stress-bearing solid such as an aircraft reinforcing plate, an automobile subframe, a wind turbine hub, or a building node. The structural force transmission frame can be a two-dimensional mechanical skeleton composed of one or more principal stress trajectories and their refined and deduplicated continuous path network, used to describe the main force flow paths inside the target stress object.

[0024] The above step S1 can be implemented according to existing technology, for example, by obtaining the structural force transmission frame of the target force-bearing object through the following steps: establish a finite element model of the target force-bearing object, perform static / steady-state analysis based on the finite element model of the target force-bearing object to obtain the principal stress field, perform trace tracing through the step method based on the principal stress field to generate the initial principal stress trace, and finally output the structural force transmission frame based on the initial principal stress trace to obtain the first structural force transmission frame.

[0025] Step S2: Discretize the first structural force transmission frame to obtain multiple discrete points.

[0026] The aforementioned discrete points can be two-dimensional coordinate points obtained by equidistant or isoparametric sampling of the first structural force transmission frame. Each discrete point can be accompanied by the principal stress direction, principal stress magnitude, and average strain energy density at that location.

[0027] Step S3: For each discrete point among multiple discrete points, take the discrete point as the starting point and the orthogonal direction corresponding to the discrete point as the first tracking direction, and perform trace tracking in the principal stress field corresponding to the target object. If the tracking enters the abnormal region, then take the direction towards the principal stress extreme point in the abnormal region as the second tracking direction, and end the trace tracking when the principal stress extreme point is reached, and obtain the candidate offspring principal stress trace. If the tracking does not enter the abnormal region, then end the trace tracking when the boundary of the principal stress field is reached, and obtain the candidate offspring principal stress trace.

[0028] The aforementioned trace tracing within the principal stress field corresponding to the target object can be performed using a step-by-step method. The step-by-step method using the `stream2` function is a simplified way to trace principal stress traces. In practical applications, trace tracing can also be performed using internal functions of other programming languages, open-source functions, or custom-written code. The `stream2` function mentioned above can be an internal function of MATLAB (abbreviation of MATrix LABoratory).

[0029] The aforementioned orthogonal directions are principal stress directions orthogonal to the principal stress directions of the traces corresponding to the discrete points. The principal stress directions of the traces are the principal stress directions corresponding to the parent principal stress traces where the discrete points are located in the first structural force transmission frame.

[0030] For principal stress trajectories, they are traced either along the direction of the first principal stress or along the direction of the second principal stress. The first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. The direction of the first principal stress is the direction of the maximum principal stress among the principal stresses experienced by the discrete point, and the direction of the second principal stress is the direction of the minimum principal stress among the principal stresses experienced by the discrete point. Therefore, the principal stress directions of the above trajectories can be divided into the directions of the first principal stress and the second principal stress. If the parent principal stress trajectory is obtained by tracing along the direction of the first principal stress, then the principal stress direction corresponding to the parent principal stress trajectory is the direction of the first principal stress, and the principal stress direction orthogonal to the direction of the first principal stress is the direction of the second principal stress. If the parent principal stress trajectory is obtained by tracing along the direction of the second principal stress, then the principal stress direction corresponding to the parent principal stress trajectory is the direction of the second principal stress, and the principal stress direction orthogonal to the direction of the second principal stress is the direction of the first principal stress.

[0031] The first principal stress σ1 and the second principal stress σ2 corresponding to the discrete points contained in the above-mentioned abnormal region have the same sign. The principal stress is generally tensile or compressive. The fact that the first principal stress and the second principal stress have the same sign can be understood as the first principal stress and the second principal stress being forces of the same nature, such as both being tensile or both being compressive.

[0032] The aforementioned principal stress field includes the magnitude and direction of the principal stress corresponding to discrete points, and the aforementioned principal stress extrema points are the coordinate points corresponding to the maximum or minimum principal stress in the abnormal region.

[0033] Step S4: Based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame, generate the final target structural force transmission frame of the target force-bearing object.

[0034] Step S4 above can be to deduplicate multiple candidate progenitor principal stress trajectories to obtain at least one candidate progenitor principal stress trajectory after deduplication, and add the at least one candidate progenitor principal stress trajectory after deduplication to the first structural force transmission frame to generate the final target structural force transmission frame of the target force-bearing object.

[0035] In this embodiment, once the trace is determined to enter a stress concentration region where σ1 and σ2 have the same sign, the stepping strategy is immediately switched to "actively climbing along the maximum principal stress gradient," and forced to terminate at the extreme point where the gradient returns to zero. This precisely pulls the trace, which would otherwise easily slip or be interrupted due to high gradient turning, towards abrupt change hotspots such as gaps and holes, and terminates it at the peak point. This achieves active connection between the principal stress trace and the stress concentration region, enabling the structural force transmission frame to automatically embed key high-stress features, significantly improving the completeness and path continuity of capturing stress change signals. Therefore, this method, guided by mechanical indicators, effectively enhances the structural force transmission frame's ability to capture key stress features, overcomes the shortcomings of traditional methods where traces are easily deviated or interrupted in stress change regions, and improves the effectiveness of generating the structural force transmission frame.

[0036] In some embodiments, step S4 may also include, but is not limited to, the following steps: Based on the obtained multiple candidate progeny principal stress trajectories and the first structural force transmission frame, the second structural force transmission frame of the target force-bearing object is generated.

[0037] If the generation of the second structural force transmission frame satisfies the iterative convergence condition, the final target structural force transmission frame of the target force-bearing object is determined based on the second structural force transmission frame.

[0038] If the generation of the second structural force transmission frame does not meet the iterative convergence condition, the second structural force transmission frame is used as the new first structural force transmission frame, and the process of discretizing the first structural force transmission frame to obtain multiple discrete points is returned.

[0039] The above-mentioned iterative convergence conditions can be convergence criteria based on mechanical properties, such as the number of iterations of the second structural force transmission frame reaching a preset number, the frame complexity of the second structural force transmission frame meeting the requirements, the overall strain energy change rate of the second structural force transmission frame being lower than a preset strain energy change rate threshold, or the contribution of the newly added offspring traces to the frame stiffness being negligible.

[0040] In one embodiment, the above-described method for generating the second structural force transmission frame of the target force-bearing object based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame can refer to the method steps described in step S4 above for generating the final target structural force transmission frame of the target force-bearing object based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame.

[0041] In some other embodiments, the process of generating a second structural force transmission frame for the target force-bearing object based on the obtained multiple candidate progeny principal stress trajectories and the first structural force transmission frame may also include, but is not limited to, the following steps: The obtained candidate progeny principal stress trajectories are corrected to obtain multiple first progeny principal stress trajectories.

[0042] Multiple first-generation principal stress traces are deduplicated to obtain at least one second-generation principal stress trace.

[0043] Obtain the average strain energy density corresponding to each of the second-generation principal stress traces in at least one second-generation principal stress trace.

[0044] Based on the average strain energy density corresponding to each second-generation principal stress trace, obtain at least one third-generation principal stress trace from the second-generation principal stress traces.

[0045] The third-generation principal stress trace is added to the first structural force transmission frame to generate the second structural force transmission frame of the target force object.

[0046] The above average strain energy density characterizes the average energy stored per unit length along the path of the corresponding second-generation principal stress trace.

[0047] The aforementioned third-generation principal stress trace is the second-generation principal stress trace corresponding to the maximum value of the average strain energy density among at least one second-generation principal stress trace. For example, if the three second-generation principal stress traces include second-generation principal stress trace 1, second-generation principal stress trace 2, and second-generation principal stress trace 3, and the average strain energy densities corresponding to second-generation principal stress trace 1, second-generation principal stress trace 2, and second-generation principal stress trace 3 are A, B, and C, respectively, where A > B > C, then the third-generation principal stress trace is second-generation principal stress trace 1.

[0048] In this embodiment, by applying the strain energy density optimization criterion, the average strain energy density on each candidate progenitor principal stress trajectory (second progenitor principal stress trajectory) after correction and screening is calculated. Only one or more candidate progenitor principal stress trajectories with the highest average strain energy density are retained and determined as new progenitor trajectories to be added to the structural force transmission frame in this iteration. Since the region with the highest strain energy density is the most critical force flow channel and weakest link in the structure, by actively selecting the path connected to this region, it is ensured that the new path is the most mechanically efficient supplement, thereby directly improving the overall mechanical rationality of the structural force transmission frame.

[0049] In some embodiments, if no second-generation principal stress trace is obtained after deduplication of multiple first-generation principal stress traces, then the first structural force transmission frame is determined as the second structural force transmission frame of the target force-bearing object. That is, after the above-mentioned correction processing of the multiple candidate principal stress traces to obtain multiple first-generation principal stress traces, the following steps may also be included: Multiple first-generation principal stress traces are deduplicated. If no first-generation principal stress trace is retained after deduplication, the first structural force transmission frame is determined as the second structural force transmission frame of the target force object.

[0050] In some embodiments, determining the final target structural force transmission frame of the target force-bearing object based on the second structural force transmission frame may mean determining the second structural force transmission frame as the final target structural force transmission frame of the target force-bearing object.

[0051] In some other embodiments, the above-described determination of the final target structural force transmission frame of the target force-bearing object based on the second structural force transmission frame may include, but is not limited to, the following steps: Replace the curve segments between all intersections in the second structural force transmission frame with straight line segments to form the final target structural force transmission frame of the target force-bearing object.

[0052] Converting curved segments into straight segments is a simple way to achieve the "shortest path for force flow". To achieve a smoother geometric transition, Bézier curves, B-spline curves, or other forms of function curves can be used to fit the trace segments between intersection points, obtaining a better geometric shape while ensuring smooth force flow.

[0053] In this embodiment, the final framework has a clear and redundant mechanical path, and it is in high agreement with the topology optimization results. It can be directly used as a high-quality initial design for subsequent topology optimization.

[0054] In some embodiments, the above-described correction process for the multiple candidate progeny principal stress trajectories to obtain multiple first progeny principal stress trajectories may include, but is not limited to, the following steps: For the first candidate trajectory among the multiple candidate progenitor principal stress trajectories obtained, if the endpoint of the first candidate trajectory is located on the free boundary of the target stressed object that is not subject to external forces, then the first intersection point of the first candidate trajectory and the second candidate trajectory is obtained, the second intersection point is determined from the first intersection point, and the trajectory corresponding to the endpoint of the first candidate trajectory from the second intersection point is removed to obtain the corrected first progenitor principal stress trajectory; if the endpoint of the first candidate trajectory is not located on the free boundary of the target stressed object that is not subject to external forces, then the original first candidate trajectory is retained.

[0055] The first candidate trace mentioned above is any one of the multiple candidate progeny principal stress traces. That is, in this embodiment, for any one of the multiple candidate progeny principal stress traces, the subsequent processing steps are performed.

[0056] The aforementioned free boundary is the boundary segment where the surface force is zero, i.e., there is no load and no constraint. For example, for the outer surface of an aircraft skin (without aerodynamic loading zone), the external air pressure and the internal cabin pressure cancel each other out, and the surface force is zero; for the edge of an opening in a building floor slab, there are no beams, walls, or equipment acting on it, and the surface force around the hole is t = 0; for the wall of an arbitrary opening in a car subframe, assuming the bolts are not tightened and there is no contact, the surface force on the hole wall is zero.

[0057] The aforementioned second candidate trace is a candidate progeny principal stress trace other than the first candidate trace among multiple candidate progeny principal stress traces. Since there is at least one candidate progeny principal stress trace other than the first candidate trace among multiple candidate progeny principal stress traces, the number of first intersection points is at least one.

[0058] The second intersection point mentioned above is the intersection point closest to the free boundary among the first intersection points.

[0059] The aforementioned multiple first-generation principal stress trajectories include the corrected first-generation principal stress trajectories and the retained original first candidate trajectories. The endpoints of the retained original first candidate trajectories are not located on the free boundaries of the target stressed object that are not subject to external forces. That is, the trajectories that need to be corrected are corrected, and the trajectories that do not need to be corrected are retained, resulting in multiple first-generation principal stress trajectories.

[0060] For example, given multiple candidate progeny principal stress trajectories including candidate progeny principal stress trajectory A, candidate progeny principal stress trajectory B, and candidate progeny principal stress trajectory C, where the endpoint of candidate progeny principal stress trajectory A is located on the free boundary of the target object free from external forces, then the first intersection point of candidate progeny principal stress trajectory A and candidate progeny principal stress trajectory B, and the first intersection point of candidate progeny principal stress trajectory A and candidate progeny principal stress trajectory C are obtained. From these two first intersection points, a second intersection point is determined, and the candidate progeny principal stress trajectories are... The trace corresponding to the endpoint of the candidate progenitor principal stress trace A from the second intersection point on line A is eliminated, resulting in the corrected first progenitor principal stress trace A. Since the endpoints of the candidate progenitor principal stress traces B and C are not located on the free boundary of the target object that is not subject to external forces, the multiple candidate progenitor principal stress traces are corrected to obtain multiple first progenitor principal stress traces, which ultimately include the first progenitor principal stress trace A, the candidate progenitor principal stress trace B, and the candidate progenitor principal stress trace C.

[0061] In this embodiment, by checking the child trace (first candidate trace), if its endpoint falls on a free boundary that is not subject to external forces, the trace is cut off at the intersection with other traces closest to the free boundary. This can automatically eliminate path segments that do not participate in effective force transmission and avoid frame redundancy.

[0062] In some embodiments, the above-described deduplication process for multiple first-generation principal stress trajectories to obtain at least one deduplicated second-generation principal stress trajectory may include, but is not limited to, the following steps: If there are duplicate principal stress traces among multiple first-generation principal stress traces, then the duplicate principal stress traces are removed from the multiple first-generation principal stress traces to obtain at least one second-generation principal stress trace after deduplication.

[0063] Among them, the aforementioned repeating principal stress trace is the first child principal stress trace that repeats the parent principal stress trace in the first structural force transmission frame among multiple first child principal stress traces.

[0064] For example, multiple first-generation principal stress traces include first-generation principal stress trace 1, first-generation principal stress trace 2, and first-generation principal stress trace 3. If first-generation principal stress trace 1 overlaps with a parent principal stress trace in the first structural force transmission frame, then first-generation principal stress trace 1 is removed from the multiple first-generation principal stress traces to obtain two second-generation principal stress traces. The two second-generation principal stress traces include first-generation principal stress trace 2 and first-generation principal stress trace 3.

[0065] In this embodiment, the parent trace has a higher priority than the child trace during deduplication. If a child trace is duplicated with a parent trace, the child trace is deleted, thus maintaining the stability of the core force transmission path.

[0066] In some embodiments, the first structural force transmission frame for obtaining the target force-bearing object described above may also include, but is not limited to, the following steps: Construct a finite element model of the target object under stress, and define the base structure corresponding to the target object under stress on the finite element model; Under the same load conditions as the target stressed object, the base structure is solved by finite element method to obtain the first principal stress and the second principal stress at each Gaussian integration point in the base structure.

[0067] Based on the first and second principal stresses at each Gaussian integration point, and the direction vectors corresponding to the first and second principal stresses at the Gaussian integration points, the principal stress direction field corresponding to the target object under stress is obtained through bilinear interpolation.

[0068] For each load application point and constraint application point in the principal stress direction field, starting from the application point, trace tracing is performed in the principal stress direction field to generate the first structural force transmission frame of the target force-bearing object.

[0069] The aforementioned process of tracing the principal stress direction field to generate the first structural force transmission frame of the target object can be achieved using a step-by-step method. The step-by-step method using the `stream2` function is a simple way to trace the principal stress lines. In practical applications, other programming languages' built-in functions, open-source functions, or custom-written code can also be used for trace tracing.

[0070] The first principal stress at the Gaussian integration point is the maximum principal stress among the principal stresses experienced at the Gaussian integration point, and the second principal stress at the Gaussian integration point is the minimum principal stress among the principal stresses experienced at the Gaussian integration point.

[0071] Specifically, this involves assigning a uniform, isotropic weak material (e.g., a material whose elastic modulus is assigned the value of a solid material) to a material with uniformity and isotropy. A "base structure" is formed by filling the entire design domain with a multiple of the specified loads and boundary conditions. A linear static finite element analysis is then performed on the base structure, yielding the stress matrix at each Gaussian integration point (usually taken as the element center) within the base structure. :

[0072] in, and They are respectively and Normal stress in the direction, This is shear stress.

[0073] Furthermore, by solving the eigenvalue problem of the stress matrix, the first principal stress at each point is obtained. (Maximum principal stress) and second principal stress The magnitude of the minimum principal stress and its corresponding direction vector and Finally, the principal stress direction field discrete at the Gaussian point is interpolated into a continuous field covering the entire design domain using a bilinear interpolation method (e.g., using the interp2 function in MATLAB), providing directional guidance for subsequent trajectory tracing.

[0074] The points of application mentioned above are either the load application points or the constraint application points.

[0075] The aforementioned principal stress direction field includes the principal stress directions at various points within the base structure region. These points may include nodes and Gaussian points.

[0076] In some embodiments, the above-mentioned load application points and constraint application points in the principal stress direction field are used as starting points, and a step method is adopted to trace the path in the principal stress direction field to generate the first structural force transmission frame of the target force object. This can be implemented with reference to the prior art.

[0077] In other embodiments, the above-described process of tracing the trajectory of each load and constraint point in the principal stress direction field, starting from the point of application, to generate the first structural force transmission frame of the target force-bearing object, may also include, but is not limited to, the following steps: For each point of application of the load and constraint in the principal stress direction field, starting from the point of application, trace tracing is performed in the principal stress direction field to generate multiple parent principal stress traces.

[0078] Set corresponding priorities for each of the multiple parent principal stress traces.

[0079] When a target principal stress trace set exists among multiple parent principal stress traces, if the priorities of the multiple parent principal stress traces included in the target principal stress trace set are different, then the parent principal stress trace with a non-highest priority in the target principal stress trace set is removed from the multiple parent principal stress traces, resulting in corrected multiple parent principal stress traces. If the priorities of the multiple parent principal stress traces included in the target principal stress trace set are the same, then the multiple parent principal stress traces included in the target principal stress trace set are merged to obtain merged principal stress traces. Furthermore, the multiple parent principal stress traces included in the target principal stress trace set are replaced with merged principal stress traces, resulting in corrected multiple parent principal stress traces.

[0080] Based on the corrected parent principal stress trajectories, the first structural force transmission frame of the target object is generated.

[0081] Among them, the aforementioned target principal stress trace set includes multiple parent principal stress traces that are repeated.

[0082] The first distance between the starting coordinates of repeated parent principal stress traces is less than a preset distance threshold, and the second distance between the corresponding ending coordinates is also less than a preset distance threshold. For example, if the distance between the starting coordinates of parent principal stress trace 1 and parent principal stress trace 2 is less than the preset distance threshold, and the distance between the ending coordinates of parent principal stress trace 1 and parent principal stress trace 2 is also less than the preset distance threshold, then parent principal stress trace 1 and parent principal stress trace 2 are repeated, and parent principal stress trace 1 and parent principal stress trace 2 can form a target principal stress trace set.

[0083] Due to the aforementioned starting point selection strategy, geometrically similar or overlapping traces may be generated (traces with very close beginning and end points). This invention simplifies this by employing a priority-based deduplication strategy. First, traces originating from concentrated load / concentrated constraint points are defined as having high priority. Second, when high-priority and low-priority traces overlap, the high-priority trace is retained. Finally, for overlapping traces of the same priority, a weighted average method under parametric coordinates is used to merge them into a new trace. The structural force transmission framework formed by this step ensures the basic connectivity of force flow.

[0084] The aforementioned trace tracing in the principal stress direction field to generate multiple parent principal stress traces can be performed using a stepping method. The stepping method using the `stream2` function is a simplified approach for tracing principal stress traces. In practical applications, trace tracing can also be performed using internal functions of other programming languages, open-source functions, or custom-written code.

[0085] In this embodiment, by improving the segmentation strategy that relies on "geometric rules" in the prior art to a mechanically driven method with strain energy density as the core criterion, it is ensured that the newly generated offspring traces will necessarily pass through the key region with the highest strain energy density in the structure, thereby significantly improving the mechanical rationality and efficiency of generating the force transmission frame, making it essentially closer to the topological optimal solution.

[0086] Meanwhile, by introducing the S-region attraction criterion, the principal stress traces can be actively connected to the stress concentration area, which effectively enhances the force transmission frame's ability to capture key stress characteristics and overcomes the shortcomings of traditional methods where the traces are prone to deviation or interruption in stress abrupt change areas.

[0087] Furthermore, by combining free boundary truncation with the high priority criterion of parent traces, redundant paths can be automatically eliminated based on mechanical logic while retaining the core force transmission framework. Thus, under the premise of ensuring force flow connectivity, an optimal force transmission framework with clear topological relationships, simplicity, and no redundancy is naturally obtained.

[0088] To better understand the above method, the embodiments of this application further illustrate the method with the following content: This invention provides a method for generating structural force transmission frames driven by mechanical principles. The core of this method lies in replacing traditional geometric rules with a series of mechanical principles to guide the progressive refinement of the force transmission frame. The method includes the following steps: Step 1: Obtain the stress field of the base structure and calculate the principal stress direction field.

[0089] This step is the foundation for all subsequent operations.

[0090] First, a homogeneous, isotropic weak material (e.g., one whose elastic modulus is assigned the value of a solid material) is considered. (Multiplied by 1) fills the entire design domain to form the "base structure".

[0091] Secondly, real loads and boundary conditions are applied to the base structure, and linear static finite element analysis is performed to obtain the stress matrix at each Gaussian integration point of the base structure (usually taken as the element center). :

[0092] in, and They are respectively and Normal stress in the direction, This is shear stress.

[0093] Furthermore, by solving the eigenvalue problem of the stress matrix, the first principal stress at each point is obtained. (Maximum principal stress) and second principal stress The magnitude of the minimum principal stress and its corresponding direction vector and Finally, the principal stress direction field discrete at the Gaussian point is interpolated into a continuous field covering the entire design domain using a bilinear interpolation method (e.g., using the interp2 function in MATLAB), providing directional guidance for subsequent trajectory tracing.

[0094] Taking an L-shaped beam as an example, the dimensionless dimensions, loads, and constraints of the design domain are as follows: Figure 2 As shown, Figure 2 This is a schematic diagram of an L-shaped beam provided in an embodiment of this application. The vertical long segment length L1=1, the horizontal long segment length L2=1, the vertical short segment length L3=0.4, the horizontal short segment length L4=0.4, and the vertically downward concentrated force P=1. Quadrilateral plane stress elements are used to mesh the design domain (e.g., using...). The grid is shown in Figures 3(a) and 3(b). The principal stress direction field includes a first principal stress direction field and a second principal stress direction field. The first principal stress direction field includes the first principal stress direction at each point, and the second principal stress direction field includes the second principal stress direction at each point. Figures 3(a) and 3(b) are schematic diagrams of the first principal stress direction field and the second principal stress direction field provided in the embodiments of this application, respectively.

[0095] Step 2: Construct the initial force transmission frame that connects the loads and constraints.

[0096] The goal of this step is to establish the most basic force flow connections between load points and constraint points. Starting from all load and constraint points, principal stress trajectories are traced to form an initial network. Specifically, for concentrated force points or single-point constraints, these are directly used as the starting points of the trajectories; for distributed loads or constraint boundaries, the extreme points of principal stresses on that boundary are selected as the starting points. Using a step-by-step method (e.g., the stream2 function in MATLAB), the trajectories are traced bidirectionally (forward and backward) along the principal stress direction field obtained in step 1, starting from each starting point, until the trajectories reach the design domain boundary.

[0097] Due to the aforementioned starting point selection strategy, geometrically similar or overlapping traces may be generated (traces with very close starting and ending points), such as... Figure 4 As shown, Figure 4 This is a schematic diagram of similar or repeated traces in the L-shaped beam example provided in the embodiments of this application. The present invention simplifies the process by using a priority-based deduplication strategy: First, traces originating from concentrated load / constraint points are defined as having high priority; second, when high and low priority traces are repeated, the high priority trace is retained; finally, for repeated traces of the same priority, a weighted average method under parametric coordinates is used to merge them into a new trace.

[0098] like Figure 5 As shown, Figure 5 This is a schematic diagram of the initial force transmission frame for the L-shaped beam example provided in this application embodiment. The initial force transmission frame formed in this step (the first structural force transmission frame mentioned above) ensures the basic connectivity of the force flow, but the path is singular and cannot form a stable support system.

[0099] Step 3: Generate candidate offspring traces.

[0100] This step aims to prepare candidate paths for the mechanical drive refinement of the force transmission frame. The parent force transmission frame (the aforementioned first structural force transmission frame) is discretized to obtain a series of candidate points. Starting from each candidate point, multiple candidate child traces (the aforementioned candidate child principal stress traces) are generated using a step-by-step method along the principal stress direction orthogonal to the parent trace (the parent principal stress trace in the aforementioned first structural force transmission frame). (That is, in the aforementioned orthogonal direction, if the parent trace is the first principal stress trace, then along the second principal stress direction, and vice versa.) Figure 6 As shown, Figure 6 A schematic diagram of candidate offspring traces for the L-shaped beam example provided in this application embodiment.

[0101] Step 4: Apply mechanical criteria to correct and screen offspring traces.

[0102] This step is the core of the invention. It introduces a series of mechanical criteria to correct candidate offspring trajectories and select the optimal path from them, thereby replacing geometric driving with mechanical driving.

[0103] First, the traces in the initial force transmission frame obtained in step 2 (performed for the first time) or the parent force transmission frame (performed subsequently) are "widened," that is, treated as solid rods with a certain width, and the material in the corresponding region of the base structure is replaced (assigning realistic material properties). Then, finite element analysis is performed again on this "frame structure" to calculate its strain energy density field. :

[0104] in, and They are respectively and The positive strain in the direction, Shear strain. This physical quantity characterizes the elastic deformation energy stored per unit volume, such as... Figure 7 As shown, Figure 7 A schematic diagram of the strain energy density field of the L-shaped beam example provided in this application embodiment.

[0105] The following correction criteria are applied in the process of generating candidate offspring traces: S-region (the aforementioned anomalous region) attraction criterion: During the trace tracing process, if it is determined that the trace has entered the S-region (i.e., the region where the first and second principal stresses have the same sign, such as...), then... Figure 8 As shown, Figure 8 (The illustration of the S-region attraction criterion for the L-shaped beam example provided in this application) directly attracts and terminates the stress at the principal stress extremum point in that region. The advantage of this improvement is that it accurately reflects the force convergence characteristics of the stress concentration region (comparable to...). Figure 6 and Figure 8 This overcomes the shortcomings of traditional methods, which are prone to trace deviation or interruption in areas of sudden stress change.

[0106] Secondly, the following correction criteria are applied in the process of obtaining the first generation principal stress trace by correcting the candidate offspring trace: Free Boundary Truncation Criterion: Examine the child trajectory; if its endpoint falls on a free boundary unaffected by external forces, truncate the trajectory at the point closest to the free boundary where it intersects with other trajectories, thus obtaining the first child principal stress trajectory. The advantage of this improvement is that it automatically eliminates path segments that do not participate in effective force transmission, avoiding frame redundancy.

[0107] The following correction criteria were applied during the screening of the principal stress traces of the second generation: Parent trace priority criterion: When determining duplicates, the parent trace has a higher priority than the child trace. If a child trace overlaps with a parent trace, the child trace is deleted from multiple first-generation principal stress traces to obtain the second-generation principal stress trace. This improvement maintains the stability of the core force transmission path.

[0108] Finally, the following correction criteria were applied during the screening of the third-generation principal stress traces: Apply the strain energy density optimization criterion. Calculate the average strain energy density on each candidate offspring trajectory after correction. Retain only the candidate offspring trajectories with the highest average strain energy density, and determine them as the new offspring trajectories (third offspring principal stress trajectories) to be added to the force transmission frame in this iteration. Figure 8 As shown. The principle behind this invention is that the region with the highest strain energy density is the most critical force flow channel and the weakest link in stiffness within the structure. By actively selecting paths connecting to this region, the invention ensures that the newly added paths are mechanically the most efficient supplement, thereby directly improving the overall mechanical rationality of the force transmission frame.

[0109] Step 5: Iterative refinement and generation of the final force transmission frame.

[0110] The new progeny traces retained after the correction and screening in step 4 are added to the existing force transmission frame to form a new frame after one iteration (the second structural force transmission frame). The process of steps 3 to 4 (i.e., generating candidate progeny traces, calculating the strain energy field based on the new frame, and correcting and screening using mechanical criteria) is repeated until the preset number of topological growth iterations (e.g., 5 times) is reached or the frame complexity meets the requirements, such as... Figure 9 As shown, Figure 9 This is a schematic diagram illustrating the iterative refinement of the L-shaped beam example provided in this embodiment.

[0111] Finally, based on the "shortest path for force flow" criterion, all curve segments between intersections in the force transmission frame after iteration are replaced with straight line segments (i.e., straight lines replace curves), forming the final form of the structural force transmission frame (e.g., ...). Figure 10 As shown, the result is obtained after 4 topological growth iterations. Figure 10 This is a schematic diagram of the target structural force transmission frame for the L-shaped beam example provided in this embodiment. The final frame has a clear and redundant mechanical path, and it highly matches the topology optimization results. It can be directly used as a high-quality initial design for subsequent topology optimization.

[0112] Explanation of alternative solutions for each step of the above implementation method: The core of this invention lies in the framework generation concept driven by the aforementioned mechanical principles, rather than certain specific computational tools or numerical methods employed in its implementation. Therefore, in practical implementation, the following known alternatives can be adopted for the following steps: Regarding the acquisition of the stress field and principal stress direction field in step 1: The finite element analysis method is not the only approach. Those skilled in the art can also use other numerical calculation methods such as the boundary element method, finite difference method, or meshless method to obtain the continuous stress field in the design domain, and then solve for the principal stresses and their directions.

[0113] Regarding principal stress tracing in steps 1 and 2: Using the stream2 function stepping method is a simple way to trace principal stress lines. In practical applications, other programming languages' built-in functions, open-source functions, or custom code can also be used for line tracing.

[0114] Regarding the calculation of the strain energy density field in step 4: The strain energy density formula This method is applicable to linear elastic materials. For other constitutive models, such as hyperelastic or elastoplastic materials, the strain energy density expression corresponding to that material model can be used for calculation, and the method described in this invention is equally applicable.

[0115] Regarding the strategy of substituting straight lines for curves in step 5: Converting curved segments into straight segments is a simple way to achieve the "shortest path for force flow". To achieve a smoother geometric transition, Bézier curves, B-spline curves, or other forms of function curves can be used to fit the trace segments between intersection points, obtaining a better geometric shape while ensuring smooth force flow.

[0116] Regarding the determination of iteration termination: In addition to the preset number of topology growths, the termination condition of the iterative refinement process can also be set according to actual needs, such as: the overall strain energy change rate of the force transmission frame is lower than a certain threshold, or the contribution of the newly added offspring traces to the frame stiffness is negligible, etc., based on convergence criteria of mechanical properties.

[0117] It should be emphasized that the above-mentioned alternatives are all known technologies in the art, and their replacement and implementation do not affect the application of the core of this invention (i.e., the series of mechanical principles) and the beneficial effects produced. Any method that uses the mechanical principles proposed in this invention to progressively generate a structural force transmission frame should fall within the protection scope of this invention.

[0118] The value and effectiveness of this invention are demonstrated as follows: Significant improvement in mechanical rationality: By introducing the "strain energy density optimization" criterion, it is ensured that each new force transmission path introduced by topological growth serves the explicit goal of connecting the most critical force flow channels. The force transmission frame generated by the method of this invention has its paths naturally distributed in the high strain energy region, which is highly consistent with the core load-bearing characteristics of the structure.

[0119] Precise capture of key mechanical features: By introducing the "S-region attraction" criterion, the method of this invention can actively identify and connect stress concentration regions. For example... Figure 8As shown, in typical stress concentration areas such as the corner of an L-shaped beam, the force transmission path is effectively guided to this area. This framework overcomes the path deviation or interruption problems that may occur at the stress gradient abrupt change in traditional methods, enabling the generated framework to more completely and accurately reflect the actual stress state of the structure.

[0120] Simplicity and practicality of the generated framework: Combining the "free boundary truncation" and "high priority of parent traces" criteria, this invention can automatically eliminate redundant paths during the iteration process, maintaining the stability of the core force transmission skeleton. The final generated force transmission framework has a clear topological relationship and no redundant branches, which not only has high mechanical efficiency but also a simple geometric form, greatly reducing the complexity of subsequent detailed design or manufacturing based on this framework.

[0121] The immense potential of this invention as a high-quality initial design: Since the force transmission frame generated by this invention is very close to the topological optimum, using it as the initial design for explicit topology optimization (such as the moving deformable component method) can effectively prevent the optimization algorithm from getting stuck in local optima due to an unreasonable initial configuration, and significantly reduce the number of iterations required for convergence. In practical engineering applications, this means a shorter design cycle and a saving of computational resources, possessing significant practical value.

[0122] To better implement the above method, embodiments of this application provide an apparatus for generating a structural force-transmitting frame, referring to... Figure 11 , Figure 11 A structural block diagram of the apparatus for generating a structural force transmission frame provided in the embodiments of this application is shown below. Figure 11 As shown, the device 110 for generating the structural force transmission frame may specifically include the following: Acquisition module 111 is used to acquire the first structural force transmission frame of the target force-bearing object; The frame discretization module 112 is used to discretize the first structural force transmission frame to obtain multiple discrete points; The trace tracking module 113 is used to track each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction, in the principal stress field corresponding to the target force-bearing object. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction, and the trace tracking ends when the principal stress extreme point is reached, obtaining a candidate offspring principal stress trace. If the tracking does not enter the abnormal region, the trace tracking ends when the boundary of the principal stress field is reached, obtaining a candidate offspring principal stress trace. Wherein, the orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point, the principal stress direction of the trace is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame, the first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign, the first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. The frame generation module 114 is used to generate the final target structural force transmission frame of the target force-bearing object based on the multiple candidate offspring principal stress trajectories and the first structural force transmission frame.

[0123] The apparatus 110 for generating a structural force transmission frame provided in this application embodiment can execute the technical solution shown in the above method embodiment. Its implementation principle and beneficial effects are similar, and will not be described again here.

[0124] Figure 12 An internal structural diagram of a computer device in one embodiment is shown. This computer device can specifically be a terminal or a server. Figure 12 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program that, when executed by the processor, enables the processor to implement an age recognition method. The internal memory may also store a computer program that, when executed by the processor, enables the processor to implement the age recognition method. Those skilled in the art will understand that... Figure 12 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0125] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of the method for generating a structural force transmission frame described above.

[0126] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, causes the processor to perform the steps of the method for generating a structural force transmission frame described above.

[0127] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0128] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims. Please enter the specific implementation details.

Claims

1. A method for generating a structural force-transmitting frame, characterized in that, The method includes: Obtain the first structural force transmission frame of the target force-bearing object; The first structural force transmission frame is discretized to obtain multiple discrete points; For each of the plurality of discrete points, starting from the discrete point and using the orthogonal direction corresponding to the discrete point as the first tracking direction, trace tracing is performed in the principal stress field corresponding to the target force-bearing object. If the tracking enters an abnormal region, the direction towards the principal stress extreme point in the abnormal region is used as the second tracking direction. The trace tracing ends when the principal stress extreme point is reached, and candidate offspring principal stress traces are obtained. If the tracking does not enter an abnormal region, the trace tracing ends when the boundary of the principal stress field is reached, and candidate offspring principal stress traces are obtained. Wherein, the orthogonal direction is the principal stress direction orthogonal to the principal stress direction of the trace corresponding to the discrete point, the principal stress direction of the trace is the principal stress direction corresponding to the parent principal stress trace where the discrete point is located in the first structural force transmission frame, the first principal stress and the second principal stress corresponding to the discrete points included in the abnormal region have the same sign, the first principal stress is the maximum principal stress among the principal stresses corresponding to the discrete point, and the second principal stress is the minimum principal stress among the principal stresses corresponding to the discrete point. Based on the obtained multiple candidate offspring principal stress trajectories and the first structural force transmission frame, the final target structural force transmission frame of the target force-bearing object is generated.

2. The method according to claim 1, characterized in that, The step of generating the final target structural force transmission frame for the target stress object based on the obtained multiple candidate progeny principal stress trajectories and the first structural force transmission frame includes: Based on the multiple candidate offspring principal stress trajectories and the first structural force transmission frame, a second structural force transmission frame for the target force-bearing object is generated. If the generation of the second structural force transmission frame satisfies the iterative convergence condition, the final target structural force transmission frame of the target force-bearing object is determined based on the second structural force transmission frame. If the generation of the second structural force transmission frame fails to meet the iterative convergence condition, the second structural force transmission frame is used as the new first structural force transmission frame, and the process returns to the step of discretizing the first structural force transmission frame to obtain multiple discrete points.

3. The method according to claim 2, characterized in that, The step of generating a second structural force transmission frame for the target stress object based on the acquired multiple candidate progeny principal stress trajectories and the first structural force transmission frame includes: The obtained candidate progeny principal stress trajectories are corrected to obtain multiple first progeny principal stress trajectories; The multiple first-generation principal stress traces are deduplicated to obtain at least one second-generation principal stress trace after deduplication. Obtain the average strain energy density corresponding to each of the at least one second-generation principal stress traces; wherein, the average strain energy density characterizes the average energy stored per unit length of the path traversed by the corresponding second-generation principal stress trace; Based on the average strain energy density corresponding to each second-generation principal stress trace, the third-generation principal stress trace among the at least one second-generation principal stress trace is obtained; wherein, the third-generation principal stress trace is the second-generation principal stress trace corresponding to the maximum value among the average strain energy densities of the at least one second-generation principal stress trace. The third-generation principal stress trace is added to the first structural force transmission frame to generate the second structural force transmission frame of the target force-bearing object.

4. The method according to claim 2, characterized in that, The step of determining the final target structural force transmission frame of the target force-bearing object based on the second structural force transmission frame includes: Replace the curve segments between all intersection points in the second structural force transmission frame with straight line segments to form the final target structural force transmission frame of the target force-bearing object.

5. The method according to claim 3, characterized in that, The process of correcting the obtained multiple candidate progeny principal stress trajectories to obtain multiple first progeny principal stress trajectories includes: For the first candidate trace among the multiple candidate child principal stress traces, if the endpoint of the first candidate trace is located on the free boundary of the target stressed object that is not subject to external forces, then the first intersection point of the first candidate trace and the second candidate trace is obtained, the second intersection point is determined from the first intersection point, and the traces corresponding to the endpoint of the first candidate trace from the second intersection point on the first candidate trace are removed to obtain the corrected first child principal stress trace; if the endpoint of the first candidate trace is not located on the free boundary of the target stressed object that is not subject to external forces, then the original first candidate trace is retained; wherein, the first candidate trace is any one of the multiple candidate child principal stress traces, the free boundary is a boundary segment with zero surface force, the second candidate trace is the candidate child principal stress trace other than the first candidate trace among the multiple candidate child principal stress traces, and the second intersection point is the intersection point closest to the free boundary among the first intersection points; The multiple first-generation principal stress traces include the corrected first-generation principal stress traces and the retained original first candidate traces.

6. The method according to claim 3, characterized in that, The process of deduplicating the plurality of first-generation principal stress traces to obtain at least one deduplicated second-generation principal stress trace includes: If there is a repeating principal stress trace among the plurality of first-generation principal stress traces, then the repeating principal stress trace is removed from the plurality of first-generation principal stress traces to obtain at least one second-generation principal stress trace after deduplication; wherein, the repeating principal stress trace is the first-generation principal stress trace among the plurality of first-generation principal stress traces that repeats the parent principal stress trace in the first structural force transmission frame.

7. The method according to claim 1, characterized in that, The first structural force transmission frame for acquiring the target force-bearing object includes: Construct a finite element model of the target force-bearing object, and define the base structure corresponding to the target force-bearing object on the finite element model; Under the same load conditions as the target stressed object, the base structure is solved by finite element method to obtain the first principal stress and the second principal stress at each Gaussian integration point in the base structure; Based on the first principal stress and the second principal stress at each Gaussian integration point, and the direction vectors corresponding to the first principal stress and the second principal stress at each Gaussian integration point, the principal stress direction field corresponding to the target stressed object is obtained by bilinear interpolation. For each load application point and constraint application point in the principal stress direction field, starting from the application point, trace tracing is performed in the principal stress direction field to generate the first structural force transmission frame of the target force-bearing object.

8. The method according to claim 7, characterized in that, For each load application point and constraint application point in the principal stress direction field, starting from the application point, a trajectory is traced in the principal stress direction field to generate the first structural force transmission frame of the target force-bearing object, including: For each load application point and constraint application point of the target stressed object in the principal stress direction field, starting from the application point, a stepping method is used to trace the trajectory in the principal stress direction field to generate multiple parent principal stress trajectories. Each of the multiple parent principal stress traces is assigned a corresponding priority. If a target principal stress line set exists among the multiple parent principal stress lines, and if the multiple parent principal stress lines included in the target principal stress line set have different priorities, then the parent principal stress line with a non-highest priority in the target principal stress line set is removed from the multiple parent principal stress lines to obtain corrected multiple parent principal stress lines; if the multiple parent principal stress lines included in the target principal stress line set have the same priority, then the multiple parent principal stress lines included in the target principal stress line set are merged to obtain merged principal stress lines, and the multiple parent principal stress lines included in the target principal stress line set are replaced with the merged principal stress lines to obtain corrected multiple parent principal stress lines; wherein, the multiple parent principal stress lines included in the target principal stress line set are repeated. Based on the corrected parent principal stress trajectories, the first structural force transmission frame of the target force-bearing object is generated.

9. A computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to perform the steps of the method as claimed in any one of claims 1 to 8.

10. A computer device comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of the method as claimed in any one of claims 1 to 8.

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