A design method and system of a multi-component controllable thermal expansion connection and integrated support dot array structure

Abstract

The application provides a design method and system for a multi-component controllable thermal expansion connection and an integrated support lattice structure, and belongs to the field of controllable thermal expansion structures. In order to solve the problems that the mapping relationship between macroscopic thermal expansion performance and lattice structure materials is not clear, there is a lack of universal design method, and the structure is relatively complex and difficult to process, the tooling support structure is decomposed into a deformation structure and a tooling structure, the target thermal expansion coefficient is substituted into a triangular lattice structure equivalent thermal expansion coefficient calculation model, the bottom length, that is, the structure material, is constrained to obtain the initial parameters of the lattice structure; then the structure is fine-tuned through finite element simulation, the influence of the actual wall thickness is eliminated and adaptive processing is performed, and finally the lattice structure design meeting the use requirements is completed. The structure thermal expansion precision obtained by the method is high, the lightweight rate is high, the cost is low, and the tooling connection demand with specific thermal expansion demand between multiple mechanisms can be effectively adapted.

Description

Technical Field

[0001] This invention relates to the field of controllable thermal expansion structure technology, and more specifically, to a design method and system for a multi-component controllable thermal expansion connection and integrated support lattice structure. Background Technology

[0002] For precision detection equipment such as optical components of space telescopes and satellite radar systems, deformation errors caused by even tiny thermal mismatches between components under variable temperature conditions can lead to significant deviations in results. Therefore, it is urgent to customize precision tooling with specific thermal expansion characteristics based on the structural service requirements to ensure the long-term stable operation of the equipment.

[0003] Currently, the solution to this type of problem is to select materials with near-zero thermal expansion properties for structural fabrication, while ensuring adequate support. For example, Invar steel exhibits near-zero expansion, with a thermal expansion ratio of approximately 1.5 × 10⁻⁶ K in the temperature range of 73 K–373 K. -6 The macroscopic thermal expansion properties of / K are obtained. However, the structure obtained by this method still differs significantly from the actual thermal expansion requirements, and a large structural density can also impose a load burden on the spacecraft's operation. Lattice structures are an effective means to achieve specific near-zero expansion structural designs. Their thermal expansion coefficient is determined by the synergy of material physical properties and structural deformation, and can be specifically designed according to operating conditions. However, the mapping relationship between macroscopic thermal expansion properties and lattice structures and materials is still unclear, lacking a universal design method, and the structure is relatively complex and difficult to manufacture.

[0004] Therefore, there is an urgent need for a design method for a multi-component thermally expandable connection and an integrated support lattice structure to achieve efficient design of multi-mechanism precision connection, ensure high-precision tooling for high-precision equipment such as the primary and secondary mirrors of the detector, and guarantee the stability of the structure operation. Summary of the Invention

[0005] The technical problem to be solved by this invention is:

[0006] To address the issues of unclear mapping relationship between macroscopic thermal expansion properties and lattice structure materials, lack of universal design methods, and relatively complex and difficult-to-manufacture structures.

[0007] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0008] This invention provides a design method for a multi-component controllable thermal expansion connection and integrated support lattice structure, comprising the following steps:

[0009] S100. Decompose the tooling support structure into deformable structures and tooling structures responsible for connecting each deformable structure. Divide the deformable structure into multiple isosceles triangular lattice cells of the same size. The isosceles triangular lattice cells are composed of two materials, including material A for the two hypotenuses and material B for the base. Obtain the target thermal expansion coefficient of the deformable structure according to the usage requirements, and select the array material of the isosceles triangular lattice cells according to the target thermal expansion coefficient. Obtain the base size limit of the isosceles triangular lattice cells according to the tooling requirements.

[0010] S200: Substitute the constraints obtained in step S100 into the equivalent thermal expansion coefficient model of the deformable structure with multiple isosceles triangular lattice cells evenly distributed, and obtain the initial structural parameter information that meets the usage requirements. This includes S210: Constructing the equivalent thermal expansion coefficient model of the deformable structure based on thermal expansion deformation, Poisson additional deformation and elastic constraint deformation; S220: Applying material and structural constraints based on requirements and obtaining structural angle parameters that meet the requirements; S230: Designing a single isosceles triangular lattice cell structure; and S240: Designing the overall deformable structure.

[0011] S300, a structure for fine-tuning deformation based on finite element simulation;

[0012] S400. Based on the deformed structure obtained in step S300, establish an overall model of the connection structure.

[0013] S500, obtaining the overall structural thermal expansion coefficient based on finite element simulation;

[0014] S600, adapts and outputs structural parameter information and material information.

[0015] Further, in step S210, the following is included:

[0016] S211. Assume the base of the isosceles triangular lattice cell is parallel to the X direction and perpendicular to the Y direction; the coefficient of thermal expansion of material A is... Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The coefficient of thermal expansion of material B is Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The included angle of the base is ;

[0017] S212. Deformation behavior analysis during free expansion.

[0018] When temperature changes If both hypotenuse A and base B undergo free expansion, then the corresponding lengths will change. and for:

[0019]

[0020] In the formula, and Let A and B be the initial lengths of the hypotenuse and the base, respectively.

[0021] S213. Axial correction considering Poisson effect.

[0022] Thermal expansion in the width and thickness directions produces additional axial deformation through Poisson's ratio. For a straight rod with an inclined side, the width change... Thickness variation and additional axial deformation They are as follows:

[0023]

[0024] Additional axial deformation for the bottom edge rod for:

[0025]

[0026] S214. Axial correction considering elastic constraints.

[0027] After considering the constraints at the vertices of the isosceles triangle lattice cell, the corresponding axial forces F on the hypotenuse and base are... A F B The elastic deformations are respectively and :

[0028]

[0029] Consider the static equilibrium and geometric constraints at the hinge point:

[0030]

[0031]

[0032] Among them, A A and A B E represents the cross-sectional area of ​​the hypotenuse straight bar element corresponding to material A and material B, respectively. A A A and E B A BThese are the axial stiffnesses of the inclined straight bar elements corresponding to materials A and B, respectively.

[0033] at this time, and for:

[0034]

[0035]

[0036] The establishment of the S215 and Y-axis equivalent thermal expansion coefficient model

[0037] For an isosceles triangular cell structure, the Y-axis dimension, i.e., the height H, undergoes... After temperature change:

[0038]

[0039] According to the definition of the coefficient of thermal expansion:

[0040]

[0041] In the formula, H0 is the initial height of the structure:

[0042] .

[0043] Further, in step S220,

[0044] For designs with a positive coefficient of thermal expansion, the coefficient of thermal expansion of the bottom material must be less than that of the hypotenuse. For structures with zero or negative expansion requirements, the coefficient of thermal expansion of the bottom material must be greater than that of the hypotenuse, thus forming a material and structural constraint.

[0045] Based on this, the thermal expansion coefficient of the deformable structure is determined. The thermal expansion coefficient of the tooling structure is positive, and the target thermal expansion coefficient of the deformable structure is lower than the overall thermal expansion coefficient. At the same time, considering the strength of the components and the usage scenario, the appropriate width and thickness are determined to form structural constraints. Substituting the above constraints into equation (10), the unique structural angle θ with the target thermal expansion coefficient can be obtained.

[0046] Furthermore, in step S230, the bottom edge L is adjusted according to the tooling connection requirements. B By imposing restrictions, the hypotenuse length L of a single triangular lattice cell can be obtained using the following formula. A And the cell height H0, thus completing the design of a single isosceles triangular lattice cell structure:

[0047]

[0048] .

[0049] Further, in step S240, the total height H of the deformable structure is determined according to the usage requirements. The deformable structure can be viewed as an array of N isosceles triangular lattice cells along the Y direction.

[0050]

[0051] The design of deformable structures is achieved by arranging isosceles triangular lattice cells based on the array number N.

[0052] Further, in step S300, the designed deformable structure is modeled using finite element methods, and predefined fields and boundary conditions are applied according to the usage requirements. The true thermal expansion coefficient of the deformable structure is obtained, and the difference between the result and the thermal expansion coefficient of the target structure is compared. The model is remodeled and analyzed again by adjusting the thickness of the bottom edge of the isosceles triangle lattice cell and the size of the structural angle, until the final deformable structure parameters that meet the usage requirements are obtained.

[0053] Furthermore, in step S400, the designed deformable structure is copied, spliced, and rotated according to requirements. Then, the tooling structure is modeled, and the two are connected to complete the overall structural modeling.

[0054] Furthermore, in step S500, for the overall finite element model of the structure established in step S400, predefined fields and boundary conditions are constrained according to the usage requirements, the true thermal expansion coefficient of the deformable structure is obtained, the difference between the result and the design is compared, and the model is remodeled and analyzed again by adjusting the thickness of the bottom edge of the individual isosceles triangle lattice cell and the size of the structural angle in S300, and finally the overall structural parameters that meet the usage requirements are obtained.

[0055] Furthermore, in step S600, the structure is rounded according to the processing requirements, and the structural parameters and material information of the lattice structure that finally meets the thermal expansion requirements of the dual temperature domain are output.

[0056] A design system for a multi-component controllable thermal expansion connection and integrated support lattice structure is provided. The system has a program module corresponding to the above steps, and executes the steps in the above-described design method for a multi-component controllable thermal expansion connection and integrated support lattice structure when running.

[0057] Compared with the prior art, the beneficial effects of the present invention are:

[0058] 1. Compared with the synthesis of materials with specific thermal expansion coefficients, this invention achieves efficient design of large-scale, high-precision specific thermal expansion structures through the coupled effects of structural deformation and material expansion. The design cycle is short and the method is universal, filling the gap in the design method of zero-expansion connection and integrated support lattice structure for high-precision components.

[0059] 2. High practicality and economic value of the design structure: The thermal expansion accuracy of the structure of this invention can be controlled within 10. -7 / K improves the accuracy of the thermal expansion coefficient by an order of magnitude compared to the existing structural material Invar. The designed structure can achieve a weight reduction rate of 70% compared to the Invar solid structure. The material system can select lower-cost titanium and aluminum alloys to replace the more expensive Invar, saving more than 80% in costs. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the deformation of the isosceles triangle lattice cell in an embodiment of the present invention;

[0061] Figure 2 This is a flowchart illustrating a design method for a multi-component controllable thermal expansion connection and integrated support lattice structure according to an embodiment of the present invention.

[0062] Figure 3 This is a structural example diagram of a space telescope in an embodiment of the present invention;

[0063] Figure 4 This is an initial model diagram of the deformable structure in an embodiment of the present invention;

[0064] Figure 5 This is a diagram showing the stress results of the finite element simulation of the deformable structure in this embodiment of the invention.

[0065] Figure 6 This is a displacement result diagram of the finite element simulation of the deformable structure in the embodiment of the present invention;

[0066] Figure 7 This is a finite element model diagram of the overall structure in an embodiment of the present invention;

[0067] Figure 8 This is a stress result diagram of the overall structure finite element simulation in the embodiment of the present invention;

[0068] Figure 9 The diagram shows the displacement results of the overall structure in the embodiment of the present invention based on the finite element simulation.

[0069] Figure label:

[0070] 1. Secondary mirror surface; 2. Secondary mirror surface fixture structure; 3. Primary and secondary mirror surface connection structure; 4. Primary mirror surface; 5. Primary mirror surface fixture structure. Detailed Implementation

[0071] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0072] Specific Implementation Plan 1: Combining Figure 1 and Figure 2 As shown, the present invention provides a design method for a multi-component controllable thermal expansion connection and integrated support lattice structure, comprising the following steps:

[0073] S100. Based on usage requirements, extract the target thermal expansion coefficient and structural constraints of the deformable structure, and select a suitable material system, including:

[0074] For any complex support structure, it can be divided into two parts: a deformable structure responsible for thermal expansion control and a tooling structure responsible for connecting the various deformable structures. The tooling structure is relatively fixed and has a small design space. Therefore, this invention designs for the deformable structure and uses an array of isosceles triangular lattice cells of the same size to make the deformable structure equivalent. The target thermal expansion coefficient of the deformable structure is obtained according to the usage requirements, and the array material of the isosceles triangular lattice cells is selected according to the target thermal expansion coefficient. The base size limit of the isosceles triangular lattice cells is obtained according to the tooling requirements.

[0075] S200. Substitute the above constraints into the equivalent thermal expansion coefficient model of the isosceles triangular dual-material lattice structure to obtain initial structural parameter information that meets the usage requirements, including:

[0076] Establishment of the equivalent thermal expansion coefficient model of S210 and dual-material isosceles triangular lattice;

[0077] S211. Basic Assumptions, Simplifications, and Model Description

[0078] Assuming that all materials are isotropic and in the elastic deformation stage during deformation; that the overall temperature field and deformation of the structure are uniform; that the nodes of the isosceles triangular lattice cells are hinged; and that only thermal expansion deformation, Poisson additional deformation, and elastic constraint deformation are considered while bending moment and shear constraint are ignored; that the second-order terms related to temperature and changes in angle before and after deformation are considered negligible; and that for any isosceles triangular lattice cell, its structure and deformation are combined... Figure 1 As shown, assume the base of the isosceles triangular lattice cell is parallel to the X direction and perpendicular to the Y direction; the hypotenuse is material A with a coefficient of thermal expansion of . Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The bottom edge is material B, with a coefficient of thermal expansion of . Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The included angle of the base is ;

[0079] S212. Deformation behavior analysis during free expansion.

[0080] When temperature changes If both hypotenuse A and base B undergo free expansion, then there will be a corresponding change in length. and :

[0081]

[0082] In the formula, and Let A and B be the initial lengths of the hypotenuse and the base, respectively.

[0083] S213. Axial corrections considering the Poisson effect, including:

[0084] Thermal expansion in the width and thickness directions will produce additional axial deformation through Poisson's ratio. For a straight rod with an inclined side, the width change... Thickness variation and additional axial deformation They are as follows:

[0085]

[0086] For the bottom edge rod, there is additional axial deformation. :

[0087]

[0088] S214. Axial correction considering elastic constraints, including:

[0089] After considering the constraints at the vertices of the isosceles triangle lattice cell, the corresponding axial forces F on the hypotenuse and base are... A F B The elastic deformations are respectively and :

[0090]

[0091] Considering the static equilibrium and geometric constraints at the hinge point, we have:

[0092]

[0093]

[0094] Among them, A A and A B E represents the cross-sectional area of ​​the hypotenuse straight bar element corresponding to material A and material B, respectively. A A A and E B A B These are the axial stiffnesses of the inclined straight bar elements corresponding to materials A and B, respectively.

[0095] At this time, there are and :

[0096]

[0097]

[0098] The establishment of the S215 and Y-axis equivalent thermal expansion coefficient model includes,

[0099] For an isosceles triangular lattice cell structure, the Y-axis dimension, i.e., the height H, undergoes... After temperature change:

[0100]

[0101] According to the definition of the coefficient of thermal expansion, we have:

[0102]

[0103] In the formula, H0 is the initial height of the structure, and we have:

[0104]

[0105] S220. Based on requirements, material and structural constraints are applied to obtain structural angle parameters that meet the requirements, including:

[0106] First, the material system is determined based on the usage requirements. For ease of control, the two materials are required to have significant differences in physical properties. For designs with a positive coefficient of thermal expansion, the coefficient of thermal expansion of the bottom material is required to be less than that of the hypotenuse. For structures with zero or negative expansion requirements, the coefficient of thermal expansion of the bottom material is required to be greater than that of the hypotenuse. This forms a material structure constraint.

[0107] Based on this, the thermal expansion coefficient of the deformable structure is determined. The thermal expansion coefficient of the tooling structure is positive. Therefore, for the deformable structure, the target thermal expansion coefficient of the deformable structure must be lower than the overall thermal expansion coefficient. At the same time, considering the strength of the component and the usage scenario, the appropriate width and thickness are determined to form structural constraints. Substituting the above constraints into equation (10), the unique structural angle θ with the target thermal expansion coefficient can be obtained.

[0108] S230, a single isosceles triangular lattice cell structure design, including:

[0109] According to the tooling connection requirements, the bottom edge L... B By imposing restrictions, the hypotenuse length L of a single isosceles triangular lattice cell can be obtained using the following formula. A And the cell height H0, thus completing the design of a single isosceles triangular lattice cell structure:

[0110]

[0111]

[0112] S240, Overall design of the deformable structure, including:

[0113] The total height H of the deformable structure is determined based on usage requirements (which is the maximum lower bound multiple of the height H0 of the isosceles triangle lattice cells with respect to the length of the deformable structure). In this case, the deformable structure can be viewed as an array of N isosceles triangle lattice cells along the Y-axis. The number of cells in the longitudinal array, i.e., the isosceles triangle lattice cells N, can be obtained from the following formula:

[0114]

[0115] The design of deformable structures is achieved by arranging isosceles triangular lattice cells based on the array number N.

[0116] S300, a finite element simulation-based fine-tuning deformation structure, including,

[0117] Finite element modeling is performed on the designed deformable structure, and predefined field and boundary conditions are imposed according to the usage requirements. The true thermal expansion coefficient of the deformable structure is obtained, and the difference between the result and the thermal expansion coefficient of the target structure is compared. The model is re-modeled and analyzed again by adjusting the thickness of the bottom edge of the isosceles triangle lattice cell and the size of the structural angle, until the final deformable structure parameters that meet the usage requirements are obtained.

[0118] S400. Based on the deformed structure obtained in step S300, establish an overall model of the connection structure, including:

[0119] The designed deformable structure is copied, spliced, and rotated according to the requirements. Then, the tooling structure is modeled, and the two are connected to complete the overall structural modeling.

[0120] S500, the overall structural thermal expansion coefficient is obtained based on finite element simulation, including,

[0121] For the overall finite element model of the structure established in step S400, predefined fields and boundary conditions are constrained according to the usage requirements. The actual thermal expansion coefficient of the deformed structure is obtained. The difference between the result and the design is compared. By adjusting the thickness of the bottom edge of the individual isosceles triangle lattice cell and the size of the structural angle in S300, the S400 step is repeated to remodel and analyze again. Finally, the overall structural parameters that meet the usage requirements are obtained.

[0122] S600, adapts and outputs structural parameter information and material information, including,

[0123] The structure is rounded according to the processing requirements, and the structural parameters and material information of the lattice structure that finally meets the thermal expansion requirements of the dual temperature domain are output.

[0124] Specific implementation scheme two: The present invention provides a design system for a multi-component controllable thermal expansion connection and integrated support lattice structure. The system has a program module corresponding to the above steps, and executes the steps in the above-mentioned design method for a multi-component controllable thermal expansion connection and integrated support lattice structure when running.

[0125] The other combinations and connections in this implementation scheme are the same as in Specific Implementation Scheme 1.

[0126] Example

[0127] For the primary and secondary mirror connection support structure 3 used in space exploration mirrors, the target is a near-zero axial expansion design between the two mirror surfaces, with the target thermal expansion performance error entering 10. -7 On the order of / K, including the following steps:

[0128] S100. Based on usage requirements, extract the target thermal expansion coefficient and structural constraints of the deformable structure, and select a suitable material system, including:

[0129] The main structure of a space exploration telescope is as follows: Figure 3As shown, the secondary mirror fixture structure 2, the primary and secondary mirror connection structure 3, and the primary mirror fixture structure 5 are the three main parts of the overall structure. Based on its actual function, the primary and secondary mirror connection structure 3 is designed as a deformable structure. The overall structure's thermal expansion target is zero expansion. To offset the positive thermal expansion of the fixture structure, the deformable structure's target is near-zero negative expansion. Therefore, the inclined edge material is selected as TC4 alloy, and the bottom edge material is selected as 7075 alloy. Their corresponding physical properties are shown in Table 1. Considering the coordination between the deformable structure and the fixture structure, as well as the mechanical performance requirements of the supporting structure, the bottom edge length L is set. A = 22 mm, bottom width w A = 5 mm, bottom edge thickness t A = 1.1 mm, hypotenuse width w B = 5 mm, hypotenuse thickness t B = 1.21 mm, completing the material and structural constraints on the triangular lattice cell structure;

[0130] Table 1

[0131]

[0132] S200. Substitute the above constraints into the equivalent thermal expansion coefficient model of the triangular dual-material lattice structure to obtain initial structural parameter information that meets the usage requirements, including:

[0133] Substituting the material and structural constraints from step S100 into the equivalent thermal expansion coefficient model of the triangular lattice cell, we obtain the characteristic angle θ (angle between the base sides):

[0134]

[0135] Correspondingly, there are the triangular lattice cell height H0 and the number of arrays N:

[0136]

[0137]

[0138] The above yields a characteristic angle θ = 36.87°, a triangular lattice cell height H0 = 9.35 mm, and an array number N = 48. Simultaneously, considering the actual structure (such as...) Figure 3 The structure consists of three deformable structures symmetrically distributed at 120°. The lower radial diameter of the three support rods is 517 mm, the upper radial diameter is 200 mm, and the axial diameter is 544 mm. Based on this, the structure is arrayed and rotated to obtain the solution structure, as shown below. Figure 4 As shown;

[0139] S300, a finite element simulation-based fine-tuning deformation structure, including,

[0140] Finite element modeling was performed on the structure designed in step S200, and the simulated temperature range was selected as 0-100 ℃, which is larger than the actual required temperature range; the simulation results are... Figure 5 and Figure 6 As shown, combined with Figure 5 As shown, the maximum stress in the structure is 0.9 MPa, which is far below the material's yield strength and falls within the elastic range; combined with Figure 6 As shown, the displacement of the top of the support rod is -0.0510193 mm, corresponding to an effective axial thermal expansion coefficient of -9.4 × 10⁻⁶ mm. -7 / K is in a state of negative expansion, with an absolute value of 10. -7 At this scale, further simulation of the overall structure can be performed;

[0141] S400. Based on the obtained deformed structure, establish an overall model of the connection structure, including:

[0142] By performing array operations on a single deformable structure, and modeling and connecting the secondary mirror fixture structure 2 and the primary mirror fixture structure 5, the overall structure of the design can be obtained, such as... Figure 7 As shown;

[0143] S500, the overall structural thermal expansion coefficient is obtained based on finite element simulation, including,

[0144] against Figure 7 The overall finite element model of the structure was established for simulation, and the results are as follows: Figure 8 , 9 As shown; combined with Figure 8 As shown, the main stress of the overall structure is concentrated at the junction of the support rod and the secondary mirror tooling structure, with a maximum stress of approximately 33 MPa, which is far below the material yield strength, and the entire structure is within the elastic deformation range; Figure 9 As shown, the overall structure deforms symmetrically, with an average displacement of -0.044098 mm for each deformed leg. The overall effective thermal expansion coefficient of the secondary mirror support is 8.1 × 10⁻⁶. -7 / K is in a state of negative expansion, with an absolute value of 10. -7 The quantity meets the design requirements;

[0145] S600, adapts and outputs structural parameter information and material information, including,

[0146] The target structure is optimized by beveling the corners, and the connection points are rounded to reduce stress concentration.

[0147] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A design method for a multi-component controllable thermal expansion connection and integrated support lattice structure, characterized in that: Includes the following steps, S100. Decompose the tooling support structure into deformable structures and tooling structures responsible for connecting each deformable structure. Divide the deformable structure into multiple isosceles triangular lattice cells of the same size. The isosceles triangular lattice cells are composed of two materials, including material A for the two hypotenuses and material B for the base. Obtain the target thermal expansion coefficient of the deformable structure according to the usage requirements, and select the array material of the isosceles triangular lattice cells according to the target thermal expansion coefficient. Obtain the base size limit of the isosceles triangular lattice cells according to the tooling requirements. S200: Substitute the constraints obtained in step S100 into the equivalent thermal expansion coefficient model of the deformable structure with multiple isosceles triangular lattice cells evenly distributed, and obtain the initial structural parameter information that meets the usage requirements. This includes S210: Constructing the equivalent thermal expansion coefficient model of the deformable structure based on thermal expansion deformation, Poisson additional deformation and elastic constraint deformation; S220: Applying material and structural constraints based on requirements and obtaining structural angle parameters that meet the requirements; S230: Designing a single isosceles triangular lattice cell structure; and S240: Designing the overall deformable structure. S300, a structure for fine-tuning deformation based on finite element simulation; S400. Based on the deformed structure obtained in step S300, establish an overall model of the connection structure. S500, obtaining the overall structural thermal expansion coefficient based on finite element simulation; S600, adapts and outputs structural parameter information and material information.

2. The design method of a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 1, characterized in that: In step S210, the following are included: S211. Assume the base of the isosceles triangular lattice cell is parallel to the X direction and perpendicular to the Y direction; the coefficient of thermal expansion of material A is... Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The coefficient of thermal expansion of material B is Poisson's ratio is The elastic modulus is The width of the inclined straight bar unit is and thickness The included angle of the base is ; S212. Deformation behavior analysis during free expansion. When temperature changes If both hypotenuse A and base B undergo free expansion, then the corresponding lengths will change. and for: In the formula, and Let A and B be the initial lengths of the hypotenuse and the base, respectively. S213. Axial correction considering Poisson effect. Thermal expansion in the width and thickness directions produces additional axial deformation through Poisson's ratio. For a straight rod with an inclined side, the width change... Thickness variation and additional axial deformation They are as follows: Additional axial deformation for the bottom edge rod for: S214. Axial correction considering elastic constraints. After considering the constraints at the vertices of the isosceles triangle lattice cell, the corresponding axial forces F on the hypotenuse and base are... A F B The elastic deformations are respectively and : Consider the static equilibrium and geometric constraints at the hinge point: Among them, A A and A B E represents the cross-sectional area of ​​the hypotenuse straight bar element corresponding to material A and material B, respectively. A A A and E B A B These are the axial stiffnesses of the inclined straight bar elements corresponding to materials A and B, respectively. at this time, and for: The establishment of the S215 and Y-axis equivalent thermal expansion coefficient model For an isosceles triangular cell structure, the Y-axis dimension, i.e., the height H, undergoes... After temperature change: According to the definition of the coefficient of thermal expansion: In the formula, H0 is the initial height of the structure: 。 3. The design method for a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 2, characterized in that: In step S220, For designs with a positive coefficient of thermal expansion, the coefficient of thermal expansion of the bottom material must be less than that of the hypotenuse. For structures with zero or negative expansion requirements, the coefficient of thermal expansion of the bottom material must be greater than that of the hypotenuse, thus forming a material and structural constraint. Based on this, the thermal expansion coefficient of the deformable structure is determined. The thermal expansion coefficient of the tooling structure is positive, and the target thermal expansion coefficient of the deformable structure is lower than the overall thermal expansion coefficient. At the same time, considering the strength of the components and the usage scenario, the appropriate width and thickness are determined to form structural constraints. Substituting the above constraints into equation (10), the unique structural angle θ with the target thermal expansion coefficient can be obtained.

4. The design method of a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 3, characterized in that: In step S230, the bottom edge L is adjusted according to the tooling connection requirements. B By imposing restrictions, the hypotenuse length L of a single triangular lattice cell can be obtained using the following formula. A And the cell height H0, thus completing the design of a single isosceles triangular lattice cell structure: 。 5. The design method for a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 4, characterized in that: In step S240, the total height H of the deformable structure is determined according to the usage requirements. The deformable structure can be visualized as an array of N isosceles triangular lattice cells along the Y direction. The design of deformable structures is achieved by arranging isosceles triangular lattice cells based on the array number N.

6. The design method of a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 5, characterized in that: In step S300, the designed deformable structure is modeled using finite element methods, and predefined fields and boundary conditions are applied according to the usage requirements. The true thermal expansion coefficient of the deformable structure is obtained, and the difference between the result and the thermal expansion coefficient of the target structure is compared. The model is remodeled and analyzed again by adjusting the thickness of the bottom edge of the isosceles triangle lattice cell and the size of the structural angle, until the final deformable structure parameters that meet the usage requirements are obtained.

7. The design method for a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 6, characterized in that: In step S400, the designed deformable structure is copied, spliced, and rotated according to requirements. Then, the tooling structure is modeled, and the two are connected to complete the overall structural modeling.

8. The design method of a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 7, characterized in that: In step S500, for the overall finite element model of the structure established in step S400, predefined field and boundary condition constraints are applied according to the usage requirements to obtain the actual thermal expansion coefficient of the deformable structure. The difference between the result and the design is compared. By adjusting the thickness of the bottom edge of the individual isosceles triangle lattice cell and the size of the structural angle in S300, the model is remodeled and analyzed again to finally obtain the overall structural parameters that meet the usage requirements.

9. The design method of a multi-component controllable thermal expansion connection and integrated support lattice structure according to claim 8, characterized in that: In step S600, the structure is rounded according to the processing requirements, and the structural parameters and material information of the lattice structure that finally meets the thermal expansion requirements of the dual temperature domain are output.

10. A design system for a multi-component controllable thermal expansion connection and integrated support lattice structure, characterized in that: The system has a program module corresponding to the steps of any one of the claims 1-9 above, and executes the steps in the above-described design method of a multi-component controllable thermal expansion connection and integrated support lattice structure when running.

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