Modelling method of multi-layer spherical space grid structure system

Abstract

The application relates to a modeling method of a multi-layer spherical space grid structure system, belonging to the technical field of architecture, and comprising the following operation steps: 1. Span, rise and net shell thickness parameters are inputted first; 2. The center position of the spherical net shell and the spherical radius are calculated through the parameters, and the upper chord plane and the lower chord plane are determined; 3. The ring number of the first-stage net shell grid is inputted, and then the splitting forms of the radial rod members of subsequent stages and the number of each splitting form are inputted; 4. The edge number sequence of the hoop polygon is obtained from the radial rod member splitting form, and the total ring number and the number of each ring number polygon are calculated according to the edge number sequence; 5. Vertical web members, upper chord rods, lower chord rods, hoop inclined web members and radial inclined web members are generated in sequence; 6. The rod members at different positions are automatically divided into different layers; 7. Each rod member is rotated by a certain angle, so that the surface of each rod member is aligned with the surface of the net shell; and 8. The result is outputted as a graphic or model file. The workload of generating and adjusting the grid is saved, and the grid division is beautiful and symmetrical.

Description

Technical Field

[0001] This invention relates to the field of architectural technology, specifically to a modeling method for a multi-layered spherical spatial grid structure system. Background Technology

[0002] With technological advancements and increased awareness of conservation, steel structure buildings, characterized by their aesthetically pleasing design, rational stress distribution, and environmental friendliness, have experienced rapid development in the field of structural design. Spatial grid structures, with their large spans, light weight, high flexibility, high strength, and complex construction, enable the creation of open and spacious interior spaces in architectural and engineering design, while providing stable and efficient solutions.

[0003] Spherical spatial meshes are a commonly used type of spatial mesh structure, and many design software programs and tools offer convenient methods for generating them. However, traditional software-generated spherical spatial meshes often exhibit uneven mesh division, specifically with the central region's mesh tending to be radially longer and circumferentially shorter, while the peripheral regions' meshes tend to be radially shorter and circumferentially longer. After generating a spherical spatial mesh using traditional software, it is often necessary to manually adjust the positions of mesh nodes and merge or split meshes to ensure uniform mesh sizes and aspect ratios approaching 1. This significantly impacts the quality and efficiency of mesh generation and further limits the applicability of spherical spatial mesh structures. Currently, there is no tool suitable for generating uniform spherical spatial meshes. Summary of the Invention

[0004] This invention primarily addresses the shortcomings of existing technologies by providing a modeling method for multi-layer spherical spatial mesh structures. This method features fully automatic mesh generation, good mesh uniformity, consistent member lengths, and eliminates the need for subsequent editing. By dividing the members of each chord layer and each web layer into different layers, the workload of generating and adjusting the mesh is reduced, while also ensuring aesthetic appeal and symmetry in the mesh division, and facilitating processing and production.

[0005] The above-mentioned technical problems of the present invention are mainly solved by the following technical solutions:

[0006] A modeling method for a multi-layer spherical spatial mesh structure system includes the following steps:

[0007] Step 1: Set the model control parameters for the spherical space mesh structure to control the sphere center position (x0, y0, z0) and the sphere radius (R). The sphere center position is the coordinate value of x0, y0 and z0.

[0008] Step 2: Using the location of the sphere's center and its radius, we can derive the equation for the sphere's surface:

[0009] (x-x0) 2 +(y-y0)2 +(z-z0) 2 =R 2 .

[0010] Step 3: Set the span (L), chord layer thickness sequence (D1, D2, D3, etc.), and target value (S) of the rod length of the spatial mesh structure to be generated. The target value of the rod length is the ideal rod length to be generated, and it also serves as the target value for mesh size adjustment.

[0011] Step 4: Initialize the number of segments in the radial mesh (N1) = 1. Based on the number of segments in the radial mesh (N1), the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L1) of the radial member using the following formula:

[0012]

[0013] Step 5: Calculate the difference (Δ1) between the representative length value (L1) of the member and the target length value input in Step 3 using the following formula. Then, start iterating the number of segments (N1) of the radial mesh. In each iteration, the number of segments (N1) of the radial mesh increases by 1 until the minimum Δ1 is found.

[0014] Δ1=|L1-S|.

[0015] Step 6: Initialize the number of segments (N2) of the first circumferential ring mesh to 4. Based on the number of segments (N2) of the first circumferential ring mesh, the optimal number of segments (N1) of the radial mesh obtained in Step 5, the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L2) of the first circumferential ring member using the following formula. The number of segments (N2) of the first circumferential ring mesh is initialized to 4 to ensure that the generated mesh is symmetrical along both the X and Y axes.

[0016]

[0017] Step 7: Calculate the difference (Δ2) between the representative length value (L2) of the member and the target length value input in Step 3 using the following formula, and begin iterating the number of segments (N2) of the circumferential first ring mesh division:

[0018] Δ2=|L2-S|.

[0019] Step 8: Divide the grid into segments (N2) from the ring to the first ring, and expand the grid outwards according to 3 forms;

[0020] Step 9: Based on the three splitting methods in Step 8, using the current ring number (NI) and the number of segments (NIL) of the circumferential mesh of the previous ring, obtain three formulas for calculating the representative length (LI) of the circumferential members of this ring:

[0021]

[0022]

[0023]

[0024] Step 10: Calculate the difference (ΔI) between the representative length value (LI) of the member and the target length value input in Step 3 using the following formula, and select the mesh splitting form corresponding to the minimum ΔI:

[0025] ΔI = |LI - S|.

[0026] Step 11: Repeat steps 8 to 10, continuously expanding the mesh outwards until NI = N1, to obtain the spherical space mesh structure chord layer 1 (see...). Figure 2 (a complete grid.)

[0027] Step 12: Based on the node coordinates (x1, y1, z1) of the chord layer 1 grid, the sphere center position (x0, y0, z0) and sphere radius (R) input in Step 1, and the chord layer thickness sequence (D1, D2, D3, ...) input in Step 3, calculate the grid node coordinates (xN, yN, zN) corresponding to chord layer N:

[0028]

[0029]

[0030]

[0031] Step 13: Using the mesh nodes of each chord layer obtained in Step 12 and their corresponding relationships, generate the vertical members, circumferential members, and radial members of the web layer.

[0032] Step 14: Automatically divide each chord layer member (chord layer 1, chord layer 2, ..., chord layer N, ...), each web layer vertical member, each web layer circumferential member, and each web layer radial member into different layers.

[0033] Step 15: Automatically adjust the orientation of each member so that the plane formed by the first and second axes of the member passes through the center of the sphere, and finally output the result as a graphic or model file.

[0034] Preferably, the input span should be smaller than the radius of the sphere. If the input span is larger than the radius of the sphere, the equation will have no solution.

[0035] As a preferred option, the input target rod length is the ideal rod length. By comparing the generated mesh rod length with the target rod length, the size and uniformity of the mesh division are determined.

[0036] Preferably, the grid is expanded outward in three forms, corresponding to the following member splitting forms: no splitting, "1 to 2", and "2 to 3". In the no-split form, the number of circumferential members in this ring is the same as the previous ring, and the members at the nodes form a cross shape. In the "1 to 2" form, the number of circumferential members in this ring is twice that of the previous ring, and each node of the previous ring is connected to three nodes of this ring, resulting in a "wood"-shaped fork in the unfolded diagram. In the "2 to 3" form, the number of circumferential members in this ring is 1.5 times that of the previous ring, with half of the nodes of the previous ring connected to two nodes of this ring, resulting in a "large"-shaped fork in the unfolded diagram; the other half of the nodes are connected to one node of this ring, resulting in a cross-shaped fork in the unfolded diagram.

[0037] As a preferred method, to ensure that the generated mesh after iteration is still symmetrical along the X and Y axes, the number of segments (N2) of the circumferential first ring mesh is increased by 4 in each iteration until the number of segments (N2) of the circumferential first ring mesh corresponding to the minimum Δ2 is found.

[0038] Preferably, the vertical members of the abdominal layer are formed by connecting the nodes of the upper grid and the corresponding nodes of the lower grid; the circumferential members of the abdominal layer are formed by connecting the nodes of the upper grid and the adjacent nodes of the same ring of the lower grid; and the radial members of the abdominal layer are formed by connecting the nodes of the upper grid and the same radial node of the outer ring of the lower grid.

[0039] The present invention can achieve the following effects:

[0040] This invention provides a modeling method for a multi-layer spherical spatial mesh structure system. Compared with existing technologies, it features fully automatic mesh generation, good mesh uniformity, consistent member lengths, and no need for subsequent editing. Dividing each chord layer and each web layer member into different layers saves the workload of generating and adjusting the mesh, while also ensuring aesthetic appeal and symmetry, and facilitating processing and production. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the modeling process of the present invention.

[0042] Figure 2 This is a cross-sectional view of the spatial grid structure system generated by the present invention.

[0043] Figure 3 This is a planar schematic diagram of the spatial grid structure system generated by the present invention.

[0044] Figure 4 This is a partial planar grid schematic diagram of the spatial grid structure system of the present invention.

[0045] Figure 5 This is a schematic diagram of the "+"-shaped bifurcation of the radial rod of the present invention without splitting.

[0046] Figure 6 This is a schematic diagram of the "wood"-shaped bifurcation of the radial rod of the present invention, which is a "1-to-2" split.

[0047] Figure 7 This is a schematic diagram of the "large" bifurcation of the radial rod in the present invention, which is a "2-to-3" split.

[0048] Figure 8 This is a schematic diagram of the complete mesh of the string layer 1 generated by the present invention.

[0049] Figure 9 This is a structural schematic diagram of the abdominal vertical rod, the abdominal circumferential rod, and the abdominal radial rod of the present invention.

[0050] Figure 10 This is a schematic diagram of the isometric structure of the present invention.

[0051] Figure 11 This is a top view of the structure of the present invention. Detailed Implementation

[0052] The technical solution of the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0053] Example: Figure 1-11 As shown, a modeling method for a multi-layer spherical spatial mesh structure system includes the following steps:

[0054] Step 1: Set the model control parameters for the spherical space mesh structure to control the sphere center position (x0, y0, z0) and the sphere radius (R). The sphere center position is the coordinate value of x0, y0 and z0.

[0055] Step 2: Using the location of the sphere's center and its radius, we can derive the equation for the sphere's surface:

[0056] (x-x0) 2 +(y-y0) 2 +(z-z0) 2 =R 2 .

[0057] Step 3: Set the span (L), chord layer thickness sequence (D1, D2, D3...), and target value (S) of the rod length of the spatial mesh structure to be generated. The target value of the rod length is the ideal rod length to be generated, and it also serves as the target value for mesh size adjustment.

[0058] The input span should be less than the radius of the sphere. If the input span is greater than the radius of the sphere, the equation will have no solution. The target value of the input rod length is the ideal rod length. By comparing the generated mesh rod length with the target rod length, the size and uniformity of the mesh division are determined.

[0059] Step 4: Initialize the number of segments in the radial mesh (N1) = 1. Based on the number of segments in the radial mesh (N1), the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L1) of the radial member using the following formula:

[0060]

[0061] Step 5: Calculate the difference (Δ1) between the representative length value (L1) of the member and the target length value input in Step 3 using the following formula. Then, start iterating the number of segments (N1) of the radial mesh. In each iteration, the number of segments (N1) of the radial mesh increases by 1 until the minimum Δ1 is found.

[0062] Δ1=|L1-S|.

[0063] Step 6: Initialize the number of segments (N2) of the first circumferential ring mesh to 4. Based on the number of segments (N2) of the first circumferential ring mesh, the optimal number of segments (N1) of the radial mesh obtained in Step 5, the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L2) of the first circumferential ring member using the following formula. The number of segments (N2) of the first circumferential ring mesh is initialized to 4 to ensure that the generated mesh is symmetrical along both the x-axis and y-axis.

[0064]

[0065] Step 7: Calculate the difference (Δ2) between the representative length value (L2) of the member and the target length value input in Step 3 using the following formula, and begin iterating the number of segments (N2) of the circumferential first ring mesh division:

[0066] Δ2=|L2-S|.

[0067] To ensure that the generated mesh remains symmetrical along the X and Y axes after iteration, the number of segments (N2) of the circumferential first ring mesh is increased by 4 in each iteration until the minimum Δ2 is found to correspond to the number of segments (N2) of the circumferential first ring mesh.

[0068] Step 8: Expand the grid outwards based on the number of segments (N2) divided from the first ring grid, according to three forms. The three forms correspond to three different member splitting patterns: no splitting, "1 to 2", and "2 to 3". In the no-split pattern, the number of members in this ring is the same as the previous ring, and the members at the nodes form a cross shape. In the "1 to 2" pattern, the number of members in this ring is twice that of the previous ring, and each node of the previous ring is connected to three nodes of this ring, resulting in a "wood" shaped branch on the unfolded diagram. In the "2 to 3" pattern, the number of members in this ring is 1.5 times that of the previous ring, half of the nodes of the previous ring are connected to two nodes of this ring, resulting in a "large" shaped branch on the unfolded diagram; the other half of the nodes are connected to one node of this ring, resulting in a cross-shaped branch on the unfolded diagram.

[0069] Step 9: Based on the three splitting methods in Step 8, using the current ring number (NI) and the number of segments (NIL) of the circumferential mesh of the previous ring, obtain three formulas for calculating the representative length (LI) of the circumferential members of this ring:

[0070]

[0071]

[0072]

[0073] Step 10: Calculate the difference (ΔI) between the representative length value (LI) of the member and the target length value input in Step 3 using the following formula, and select the mesh splitting form corresponding to the minimum ΔI:

[0074] ΔI = |LI - S|.

[0075] Step 11: Repeat steps 8 to 10, continuously expanding the mesh outwards until NI = N1, to obtain the spherical space mesh structure chord layer 1 (see...). Figure 2 (a complete grid.)

[0076] Step 12: Based on the node coordinates (x1, y1, z1) of the chord layer 1 grid, the sphere center position (x0, y0, z0) and sphere radius (R) input in Step 1, and the chord layer thickness sequence (D1, D2, D3…) input in Step 3, calculate the grid node coordinates (xN, yN, zN) corresponding to chord layer N:

[0077]

[0078]

[0079]

[0080] Step 13: Using the chord-layer mesh nodes and their corresponding relationships obtained in Step 12, generate the web vertical members, web circumferential members, and web radial members. Web vertical members are formed by connecting the upper mesh nodes and corresponding nodes of the lower mesh; web circumferential members are formed by connecting the upper mesh nodes and adjacent nodes of the same ring in the lower mesh; web radial members are formed by connecting the upper mesh nodes and the same radial node of the outer ring of the lower mesh.

[0081] Step 14: Automatically divide each chord layer member (chord layer 1, chord layer 2, ... chord layer N...), each web layer vertical member, each web layer circumferential member, and each web layer radial member into different layers.

[0082] Step 15: Automatically adjust the orientation of each member so that the plane formed by the first and second axes of the member passes through the center of the sphere, and finally output the result as a graphic or model file.

[0083] The specific steps for inputting parameters are as follows:

[0084] 1) First, enter the center position of the sphere (0, 0, -40000) and the radius of the sphere (60000).

[0085] 2) Calculate the equation of the sphere using the above parameters.

[0086] 3) Input the span (80000), chord layer thickness sequence (0, -1600), and target value of rod length (3000) of the spatial mesh structure to be generated.

[0087] 4) Initialize the number of radial mesh segments (N1) = 1, calculate the representative length value (L1) of the radial member, and calculate the difference (Δ1) between the target length values. Iterate the number of radial mesh segments (N1), increasing by 1 each time, until the number of radial mesh segments (N1) corresponding to the minimum Δ1 is found. Finally, in this embodiment, N1 = 15 is obtained.

[0088] 5) Initialize the number of segments (N2) of the first circumferential ring mesh to 4. Calculate the representative length value (L2) of the first circumferential ring member and the difference (Δ2) between the target member length values. Iterate the number of segments (N2) of the first circumferential ring mesh, increasing by 4 each time, until the minimum Δ2 corresponds to the number of segments (N2) of the first circumferential ring mesh. Finally, in this embodiment, N2 = 8.

[0089] 6) Further expand the grid outward according to the three grid expansion forms until NI = N1. The final ring number sequence obtained in this embodiment is 8, 12, 24, 24, 36, 36, 36, 36, 72, 72, 72, 72, 72, 72, 72.

[0090] 7) Calculate the grid nodes corresponding to chord layer N based on the grid nodes of chord layer 1.

[0091] 8) Generate the vertical members of the periphery, the circumferential members of the periphery, and the radial members of the periphery in sequence.

[0092] 9) Automatically divide the rods in different parts into different layers.

[0093] 10) Rotate each member by a certain angle so that the surface of each member is aligned with the surface of the mesh shell.

[0094] 11) Output the results as a graphic or model file.

[0095] In summary, the modeling method for this multi-layered spherical spatial mesh structure system features fully automatic mesh generation, good mesh uniformity, consistent member lengths, and no need for subsequent editing. Dividing each chord layer and each web layer member into different layers saves the workload of generating and adjusting the mesh, while also ensuring aesthetic appeal and symmetry, and facilitating fabrication and production.

[0096] The above description is only a specific embodiment of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present invention are covered by the patent scope of the present invention.

Claims

1. A modeling method for a multi-layer spherical spatial mesh structure system, characterized in that... The following steps are included: Step 1: Set the model control parameters for the spherical space mesh structure to control the sphere center position (x0, y0, z0) and the sphere radius (R). The sphere center position is set as the coordinate values ​​of x0, y0 and z0. Step 2: Using the location of the sphere's center and its radius, we can derive the equation for the sphere's surface: ； Step 3: Set the span (L), chord layer thickness sequence (D1, D2, D3, etc.), and target value (S) of the rod length of the spatial mesh structure to be generated. The target value of the rod length is the ideal rod length to be generated, and it also serves as the target value for mesh size adjustment. Step 4: Initialize the number of segments in the radial mesh (N1) = 1. Based on the number of segments in the radial mesh (N1), the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L1) of the radial member using the following formula: ； Step 5: Calculate the difference (Δ1) between the representative length value (L1) of the member and the target length value input in Step 3 using the following formula. Then, start iterating the number of segments (N1) of the radial mesh. In each iteration, the number of segments (N1) of the radial mesh increases by 1 until the minimum Δ1 is found. ； Step 6: Initialize the number of segments (N2) of the first circumferential ring mesh to 4. Based on the number of segments (N2) of the first circumferential ring mesh, the optimal number of segments (N1) of the radial mesh obtained in Step 5, the spherical equation generated in Step 2, and the span input in Step 3, calculate the representative length value (L2) of the first circumferential ring member using the following formula. The number of segments (N2) of the first circumferential ring mesh is initialized to 4 to ensure that the generated mesh is symmetrical along both the X and Y axes. ； Step 7: Calculate the difference (Δ2) between the representative length value (L2) of the member and the target length value input in Step 3 using the following formula, and begin iterating the number of segments (N2) of the circumferential first ring mesh division: ； Step 8: Divide the grid into segments (N2) from the ring to the first ring, and expand the grid outwards according to 3 forms; Step 9: Based on the three splitting methods in Step 8, using the current ring number (NI) and the number of segments (NIL) of the circumferential mesh of the previous ring, obtain three formulas for calculating the representative length (LI) of the circumferential members of this ring: Step 10: Calculate the difference (ΔI) between the representative length value (LI) of the member and the target length value input in Step 3 using the following formula. The minimum ΔI corresponds to the mesh splitting form: ； Step 11: Repeat steps 8 to 10 to continuously expand the mesh outward until NI=N1, to obtain the complete mesh of chord layer 1 of the spherical space mesh structure; Step 12: Based on the node coordinates (x1, y1, z1) of the chord layer 1 grid, the sphere center position (x0, y0, z0) and sphere radius (R) input in Step 1, and the chord layer thickness sequence (D1, D2, D3, ...) input in Step 3, calculate the grid node coordinates (xN, yN, zN) corresponding to chord layer N: ； ； ； Step 13: Using the mesh nodes of each chord layer obtained in Step 12 and their corresponding relationships, generate the vertical members, circumferential members, and radial members of the web layer; Step 14: Automatically divide each chord layer member (chord layer 1, chord layer 2, ..., chord layer N, ...), each web layer vertical member, each web layer circumferential member, and each web layer radial member into different layers. Step 15: Automatically adjust the orientation of each member so that the plane formed by the first and second axes of the member passes through the center of the sphere, and finally output the result as a graphic or model file.

2. The modeling method for a multi-layer spherical spatial mesh structure system according to claim 1, characterized in that: The input span should be smaller than the radius of the sphere. If the input span is larger than the radius of the sphere, the equation will have no solution.

3. The modeling method for a multi-layer spherical spatial mesh structure system according to claim 1 or 2, characterized in that: The input target rod length is the ideal rod length. By comparing the generated mesh rod length with the target rod length, the size and uniformity of the mesh division are determined.

4. The modeling method for a multi-layer spherical spatial mesh structure system according to claim 1, characterized in that: There are three forms of outward grid expansion, corresponding to the member splitting forms: no splitting, "1 to 2", and "2 to 3". In the no-split form, the number of circumferential members in this ring is the same as the number of circumferential members in the previous ring, and the members at the nodes form a "+" shape. In the "1 to 2" form, the number of circumferential members in this ring is twice the number of circumferential members in the previous ring, and each node of the previous ring is connected to three nodes of this ring, showing a "wood"-shaped fork in the unfolded diagram. In the "2 to 3" form, the number of circumferential members in this ring is 1.5 times the number of circumferential members in the previous ring, half of the nodes of the previous ring are connected to two nodes of this ring, showing a "large"-shaped fork in the unfolded diagram; the other half of the nodes are connected to one node of this ring, showing a "+"-shaped fork in the unfolded diagram.

5. The modeling method for a multi-layer spherical spatial mesh structure system according to claim 1, characterized in that: To ensure that the generated mesh remains symmetrical along the X and Y axes after iteration, the number of segments (N2) of the circumferential first ring mesh is increased by 4 in each iteration until the minimum Δ2 is found to correspond to the number of segments (N2) of the circumferential first ring mesh.

6. The modeling method for a multi-layer spherical spatial mesh structure system according to claim 1, characterized in that: The vertical members of the abdominal layer are formed by connecting the nodes of the upper grid and the corresponding nodes of the lower grid; the circumferential members of the abdominal layer are formed by connecting the nodes of the upper grid and the adjacent nodes of the same ring of the lower grid; the radial members of the abdominal layer are formed by connecting the nodes of the upper grid and the same radial node of the outer ring of the lower grid.

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