Method, device, equipment and medium for designing machine tool support structure

Abstract

The application provides a machine tool support structure design method, device, equipment and medium, and relates to the technical field of data processing, wherein the method comprises the following steps: constructing a finite element model of a machine tool support structure, and defining a design region in the finite element model; determining weight values corresponding to pose change information of a moving part in each operating condition; based on the weight values, a design response index determined according to a design requirement index of the support structure, a target function and a constraint condition, performing optimization design of the design region in the finite element model, and determining a design result of the support structure. By integrating the components and component junctions of the support structure into a unified design region, considering the weights of the machine tool under multiple operating conditions, and performing collaborative topology optimization, the defects of stiffness mismatch between the structures caused by separate design are solved, the stiffness matching between the structures after optimization design is ensured, and the design accuracy and performance of the machine tool support structure are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data processing, and in particular to a design method, device and equipment of a machine tool support structure and a medium. BACKGROUND

[0002] The support structure of a machine tool is a core component of the machine tool, mainly including a bed, a column, a beam, a foot, etc., and the structures are connected to each other through a joint, thereby forming the main body of the machine tool support structure, which plays a key role in energy exchange, mechanical support and heat dissipation, etc., and has a great influence on the performance of the machine tool. The performance of the key support structure of the machine tool directly affects the machining precision and efficiency of the machine tool, and how to effectively design the reasonable matching of the support structure and the joint is one of the key problems to be solved in the existing machine tool structure design.

[0003] The existing machine tool support structure design generally adopts analogy and experience methods, and the existing design method has no scientific theoretical data to support, and cannot determine whether the structure design has redundant places, resulting in the mismatch of the stiffness between the structures, and low design precision of the machine tool support structure. SUMMARY

[0004] The present application provides a design method, device and equipment of a machine tool support structure, which solves the technical defects that the existing machine tool support structure design method has no scientific theoretical data to support, and cannot determine whether the structure design has redundant places, resulting in the mismatch of the stiffness between the structures, and improves the design precision of the machine tool support structure.

[0005] The present application provides a design method of a machine tool support structure, which comprises the following steps:

[0006] A finite element model of the support structure of the machine tool is constructed, and a design region is defined in the finite element model; the design region includes components and component joints of the support structure;

[0007] Based on the pose change information of the moving components of the machine tool under each operating condition, the weight value of the machine tool under each operating condition is determined;

[0008] Based on the weight value and the design requirement index of the support structure, the design response index, the objective function and the constraint condition of the support structure are determined;

[0009] Based on the design response index, the objective function and the constraint condition, the optimization design of the design region in the finite element model is performed to determine the design result of the support structure.

[0010] According to the method for designing a machine tool support structure provided by the application, the weight value of the machine tool in each operation condition is determined based on the position change information of the moving part in the machine tool in each operation condition, and the method comprises the following steps:

[0011] The stiffness value of the machine tool in each operation condition is determined based on the position change information of the moving part in each operation condition; the stiffness value comprises a dynamic stiffness value, a static stiffness value and a thermal stiffness value;

[0012] The weight value in each operation condition is determined based on the stiffness value of the machine tool in each operation condition.

[0013] According to the method for designing a machine tool support structure provided by the application, the design response index comprises one or more of the deformation value, the modal frequency value, the flexibility index, the temperature value, the volume fraction value and the mass information of each part in the support structure; the flexibility index is determined by the weight value in each operation condition;

[0014] The target function comprises one or more of the maximum structural stiffness, the minimum temperature standard deviation, the minimum volume fraction value, the minimum weighted strain energy and the minimum flexibility index;

[0015] The constraint condition comprises one or more of the modal frequency constraint, the deformation value constraint of different parts, the mass fraction constraint, the draw constraint and the minimum member size constraint.

[0016] According to the method for designing a machine tool support structure provided by the application, the weight value in any operation condition is determined based on the ratio of the machine tool stiffness value in the current condition to the sum of the machine tool stiffness values in all conditions.

[0017] According to the method for designing a machine tool support structure provided by the application, the method comprises the following steps:

[0018] The internal rib plate of the support structure is filled as a solid to construct a rib-free frame of the support structure;

[0019] The stiffness parameter of the machine tool foot joint, the screw joint parameter between the machine tool support structures and the material parameter of the support structure are defined in the rib-free frame to obtain the finite element model of the support structure.

[0020] According to the method for designing a machine tool support structure provided by the application, the stiffness parameter of the machine tool foot joint is determined based on the normal stiffness and the tangential stiffness of the machine tool foot joint;

[0021] The screw joint parameters are determined based on screw parameter information and the number of screws between components of the support structure.

[0022] According to the machine tool support structure design method provided by the application, the design response index, the objective function and the constraint condition are used to perform the optimization design of the design region in the finite element model, and the design result of the support structure is determined.

[0023] The design response index, the objective function and the constraint condition are used to perform the optimization design of the design region in the finite element model, and the layout of the rib plate, the layout of the anchor, the number of anchors and the layout of the screw joint in the support structure are determined.

[0024] The application further provides a machine tool support structure design device, which comprises the following modules.

[0025] A model construction module is configured to construct a finite element model of a support structure of a machine tool and define a design region in the finite element model; the design region comprises components of the support structure and component joints.

[0026] A weight calculation module is configured to determine a weight value of the machine tool in each operating condition based on pose change information of a moving component of the machine tool in each operating condition.

[0027] A design module is configured to determine a design response index, an objective function and a constraint condition of the support structure based on the weight value and a design requirement index of the support structure.

[0028] A design result determination module is configured to perform the optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determine a design result of the support structure.

[0029] The application further provides an electronic device, which comprises a memory, a processor and a computer program stored in the memory and running on the processor; when the processor executes the program, the design method of the machine tool support structure is realized.

[0030] The application further provides a non-transitory computer readable storage medium, which stores a computer program; when the computer program is executed by a processor, the design method of the machine tool support structure is realized.

[0031] The application provides a design method, device, equipment and medium of a machine tool support structure, which integrates components and component combination parts of the support structure into a unified design area, comprehensively considers pose change information of the machine tool under multiple operating conditions and gives different weights, and performs collaborative topology optimization. A globally optimal support structure can be obtained from the initial stage of design, the defects of mismatching of stiffness between structures caused by separate design are fundamentally solved, the matching of stiffness between structures after optimization design is ensured, and therefore the design precision of the machine tool support structure and the overall performance of the machine are significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0033] Figure 1 FIG. 1 is a flowchart of the design method of the machine tool support structure provided by the application.

[0034] Figure 2 FIG. 2 is a schematic diagram of the machine tool support structure provided by the application.

[0035] Figure 3 FIG. 3 is a schematic diagram of the design flow provided by the application.

[0036] Figure 4 FIG. 4 is a flowchart of the collaborative topology optimization design of the machine tool support structure provided by the application.

[0037] Figure 5 FIG. 5 is a schematic diagram of the stiffness change value of the machine tool moving part in different positions provided by the application.

[0038] Figure 6 FIG. 6 is a schematic diagram of the machine tool structure containing the moving part provided by the application.

[0039] Figure 7 FIG. 7 is a schematic diagram of the stiffness value determination flow provided by the application.

[0040] Figure 8 FIG. 8 is a schematic diagram of the weight value of the moving part in different positions provided by the application.

[0041] Figure 9 FIG. 9 is a schematic diagram of the locking connection between the foot and the foundation provided by the application.

[0042] Figure 10 FIG. 10 is a schematic diagram of the elastic connection between the foot and the foundation provided by the application.

[0043] Figure 11 is a variation curve schematic diagram of a support foot normal vector rigidity value provided by the present application.

[0044] Figure 12 is a variation curve schematic diagram of a support foot tangential vector rigidity value provided by the present application.

[0045] Figure 13 is a screw joint parameter determination flow schematic diagram provided by the present application.

[0046] Figure 14 is a variation schematic diagram of an optimized performance index provided by the present application.

[0047] Figure 15 is a structure schematic diagram of a machine tool support structure part design device provided by the present application.

[0048] Figure 16 is a structure schematic diagram of an electronic device provided by the present application.

[0049] Reference signs:

[0050] 101: crossbeam; 102: screw joint; 103: bed; 104: foot joint;

[0051] 105: Z-axis plate; 106: sliding body; 107: worktable. DETAILED DESCRIPTION

[0052] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below in combination with the drawings in the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the protection scope of the present application.

[0053] Figure 1 is a flow schematic diagram of a machine tool support structure part design method provided by the present application, as shown in Figure 1 , the method comprises the following:

[0054] Step 110, constructing a finite element model of a support structure part of a machine tool, and defining a design region in the finite element model; the design region comprises components of the support structure part and component joints;

[0055] Step 120, determining weight values of the machine tool in each running working condition based on pose change information of a moving component in the machine tool in each running working condition;

[0056] Step 130, determining the design response index, the objective function and the constraint condition of the support structure based on the weight value and the design requirement index of the support structure;

[0057] Step 140, performing the optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determining the design result of the support structure.

[0058] The execution subject of the machine tool support structure design method provided by the present application can be an electronic device, a component in an electronic device, an integrated circuit, or a chip. The electronic device can be a mobile electronic device or a non-mobile electronic device. Illustratively, the mobile electronic device can be a mobile phone, a tablet computer, a notebook computer, a palm computer, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), and the non-mobile electronic device can be a server, a network attached storage (NAS), or a personal computer (PC), etc., which are not specifically limited by the present application.

[0059] The technical solutions of the present application will be described in detail below with the computer executing the machine tool support structure design method provided by the present application as an example.

[0060] In step 110, a finite element model of the support structure of the machine tool is constructed, and a design region is defined in the finite element model.

[0061] The finite element model in the present application is a digital model for analyzing physical properties such as mechanics and heat by discretizing a complex continuous structure into a finite number of elements.

[0062] In the present application, a finite element model of the entire support structure of the machine tool needs to be constructed first. It should be noted that, as shown in the machine tool support structure schematic diagram provided by the present application, the support structure of the machine tool generally includes the core load-bearing components of the machine tool, specifically including a cross beam 101, a screw joint 102, a bed body 103, and a foot joint 104, etc. Figure 2 The machine tool support structure provided by the present application is shown in the schematic diagram, and the machine tool support structure generally includes the core load-bearing components of the machine tool, specifically including a cross beam 101, a screw joint 102, a bed body 103, and a foot joint 104, etc.

[0063] Design region is the volume space specified in the finite element model, which allows the material distribution to be changed during the optimization process. Defining the design region is the prerequisite for optimization design. In the present invention, the design region includes the components of each support structure. Among them, the components include not only the components themselves but also the designable space inside the components. For example, the cavity for arranging the rib plate. The design region also includes the joint region between the components. By taking the components and the joints as the design region at the same time, the collaborative optimization of the two can be realized, and the problem of stiffness mismatch or stress concentration caused by separate design in the design can be avoided.

[0064] Optionally, the design region of the foot joint includes but is not limited to a ring-shaped region arranged at the corner point of the bed based on the shape of the bed, and the width of the ring-shaped region is the size of the nominal contact area between the actual foot and the ground. The equivalent mode of the foot joint includes virtual material and equivalent by using three-dimensional nonlinear spring element. The three-dimensional nonlinear spring element is applied to each node on the lower side of the ring-shaped region, and the stiffness value of each node is determined by the obtained unit area stiffness value, the area of the ring-shaped region and the number of nodes divided.

[0065] In step 120, based on the pose change information of the moving components in the machine tool under each operating condition, the weight value of the machine tool under each operating condition is determined.

[0066] It should be noted that in actual work, the moving components such as the worktable and the spindle box of the machine tool will be in different positions, and each position combination constitutes an operating condition. For example, several positions such as the origin, midpoint and endpoint of the moving components in different machining strokes can be selected as the operating conditions for analysis. The equivalent mode of the moving components includes but is not limited to mass center equivalence, force equivalence, etc., and the mass center equivalence includes but is not limited to the position of the mass center and three-dimensional moment of inertia, etc.

[0067] The pose change information is used to represent the pose change of the machine tool caused by the moving stroke of the components, the deformation of the machine tool under load, the vibration mode, thermal deformation, etc. under different operating conditions. The weight value is a numerical coefficient, which is used to represent the importance degree of different operating conditions in the overall optimization target. For example, if it is found through analysis that the stiffness value of the machine tool under a certain operating condition is higher, a higher weight value can be assigned to this operating condition, so that the optimization design process will focus on improving the performance under this operating condition.

[0068] In step 130, based on the weight value and the design requirement index of the support structure, the design response index, the objective function and the constraint condition of the support structure are determined.

[0069] The design requirement index is a performance requirement index of the machine tool in the design process, for example, the machine tool as a whole has high stiffness, high natural frequency, good thermal stability, and as light a weight as possible corresponding to specific index values. The design response index is a performance parameter that needs to be monitored in the optimization process, which is the basis of the objective function and the constraint condition. The objective function is the guide of optimization, that is, it is hoped that one or more design response indexes reach the optimal value, for example, the total strain energy of the structure is minimized or the weight is lightest. The constraint condition is the boundary condition that the optimization result must satisfy to ensure the usability of the design result. For example, the minimum natural frequency of the machine tool can be constrained to be not lower than a certain specific value to avoid coincidence with the cutting chatter frequency; or the displacement of the tool point under a certain load is constrained to be not more than a certain allowable value to ensure the machining accuracy.

[0070] The determination of the design response index, the objective function and the constraint condition will comprehensively consider the weight value obtained in the previous step. For example, the objective function can be set as the sum of the weighted strain energy under all working conditions, so as to realize the optimal overall stiffness under multiple working conditions.

[0071] In step 140, based on the design response index, the objective function and the constraint condition, the optimization design of the design area in the finite element model is performed to determine the design result of the support structure.

[0072] The specific design analysis process can be as follows Figure 3 As shown in the design flowchart provided by the present application, after the finite element model of the support structure is constructed and the design area is defined, the design response index can be monitored in the design process to perform iterative calculation on the design area based on the topology optimization algorithm under the premise of meeting all constraint conditions, with the purpose of realizing the objective function. Based on the topology optimization algorithm, an automatic optimization design process can be realized, and the design result of the machine tool support structure is determined by computer solution. Optionally, the topology optimization algorithm includes the variable density method, the progressive optimization algorithm, the level set method, etc.

[0073] The design result can include the optimal layout of materials and components, for example, the layout and number of foot joints, the topology optimization shape of screw joints, the layout of rib plates of the machine tool bed, column, beam, etc. The design result can provide a scientific design reference for engineers for subsequent structure concretization design.

[0074] Optionally, after obtaining the design result, the design result can be further optimized. Specifically, structure casting review and size optimization can be performed based on the design result, that is, the design scheme meeting the requirements can be solved in the design stage, and the stiffness matching design of the machine tool key structure and its joint is realized, which provides a scientific method for solving the reasonable design of the machine tool support structure in the design stage.

[0075] Specifically, the process based on the structure casting review and size optimization can include:

[0076] The casting review is performed to determine whether the casting requirements are met and local adjustment is performed.

[0077] The local adjustment includes but is not limited to adjustment of casting fillet, chamfer adjustment, adjustment of thermal joint, drawing of weight reduction hole, determination of sand outlet hole position, etc.

[0078] The structure satisfying the casting requirements is subjected to size optimization design.

[0079] The size optimization analysis content includes sensitivity analysis of key dimensions and optimization targets to obtain the corresponding relationship between each structure size and the optimization target, and the value range of the key dimensions should be evaluated in combination with the actual casting difficulty.

[0080] The optimization target includes but is not limited to the stiffness value and natural frequency under a given working condition.

[0081] The application also provides a collaborative topology optimization design process of a machine tool support structure, as shown in the collaborative topology optimization design flowchart of the machine tool support structure. Figure 4 The collaborative topology optimization design process of the machine tool support structure provided by the application can specifically include:

[0082] Based on the experiment, the stiffness curve value of the unit area of the foundation joint is obtained.

[0083] According to the screw specifications, number, etc. of the machine tool screw joint, the material property parameters of the screw joint between each part in the machine tool support structure are determined.

[0084] The finite element model of the frame without rib plate is established, and the design area of each part and joint in the support structure is defined.

[0085] Multi-working condition integrated analysis considering pose change is considered.

[0086] The topology optimization analysis process is defined.

[0087] Based on the design response index, objective function and constraint condition, the optimization design of the design area in the finite element model is performed, and the design result is output.

[0088] The finite element analysis model is obtained, and the model is reconstructed to construct a new size model.

[0089] The casting review is performed to determine whether the casting requirements are met and local adjustment is performed.

[0090] The structure satisfying the casting requirements is subjected to size optimization design.

[0091] The structure model of each support satisfying the requirements is obtained.

[0092] The design method of the machine tool support structure provided by the application can obtain a globally optimal support structure from the initial stage of design, fundamentally solve the defects of stiffness mismatch between structures caused by separate design, ensure the stiffness matching between structures after optimization design, and significantly improve the design accuracy of the machine tool support structure and the overall performance of the machine.

[0093] In one embodiment, the weight value of the machine tool in each operating condition is determined based on the position change information of the moving part in the machine tool in each operating condition, including:

[0094] The stiffness value of the machine tool in each operating condition is determined based on the position change information of the moving part in each operating condition; the stiffness value includes dynamic stiffness value, static stiffness value and thermal stiffness value;

[0095] The weight value of each operating condition is determined based on the stiffness value of the machine tool in each operating condition.

[0096] It can be understood that, since the machine tool generally includes a moving part, and the parts in the machine tool will change in stiffness value under different operating conditions due to the influence of working vibration frequency or working heat generated during work. The stiffness value will change when the moving part is in different positions, which can be specifically as follows Figure 5 The machine tool moving part in different positions provided by the application is shown in the stiffness change value diagram. The horizontal coordinate represents the moving part in different positions, and the vertical coordinate represents different stiffness values.

[0097] As Figure 6 The machine tool structure provided by the application includes a cross beam 101, a bed body 103, a Z-axis plate 105, a sliding body 106 and a workbench 107.

[0098] It should be noted that the stiffness value is a key indicator for measuring the deformation resistance of the machine tool. In the application, the stiffness value specifically includes dynamic stiffness value, static stiffness value and thermal stiffness value.

[0099] The dynamic stiffness value is used to represent the ability of the machine tool to resist deformation and vibration under dynamic load (such as cutting force fluctuation, start-stop impact). It can be obtained by modal analysis and harmonic response analysis, and is related to the natural frequency and mode shape of the machine tool. The static stiffness value is used to represent the ability of the machine tool to resist deformation under static load (such as gravity, constant cutting force). It can be obtained by static analysis, and the displacement of the key point under a specific load is calculated. The thermal stiffness value is used to represent the ability of the machine tool to resist thermal deformation caused by heat sources (such as motors, spindle heating). It is the structural displacement caused by temperature change. By performing dynamic, static, and thermal analysis for each operating condition, one or more comprehensive stiffness values of the machine tool under the operating condition can be obtained.

[0100] It can be understood that the stiffness of the machine tool under different operating conditions is different. Therefore, a functional relationship between the weight value and the stiffness value can be established. For example, the weight value can be proportional or inversely proportional to the stiffness value, or determined by a more complex functional relationship, to ensure that the optimization design process can target to strengthen the weak links. The specific determination process is shown in the following figure: Figure 7 The stiffness value determination process diagram provided by the present application is shown. After constructing a whole-machine collaborative topology finite element analysis model, the deformation value, natural frequency, temperature value, and stress value, etc. key performance indicators are extracted for the machine tool under various different operating conditions. Then, based on the stiffness value and other analysis results under each operating condition, a weight coefficient is calculated for each operating condition. Finally, the weighted strain energy or flexibility index is determined based on these weight coefficients.

[0101] The weight values of the moving parts at different positions obtained can be as shown in the following figure: Figure 8 The weight values of the moving parts at different positions provided by the present application are shown in the following figure. When the moving part is at position 0, the determined weight coefficient is 0.36; when the moving part is at position 250, the determined weight coefficient is 0.32; when the moving part is at position 500, the determined weight coefficient is 0.32.

[0102] In one embodiment, the design response indicators include one or more of the deformation value, modal frequency value, flexibility index, temperature value, volume fraction value, and mass information of each component in the support structure; the flexibility index is determined by the weight value under each operating condition;

[0103] The objective function includes one or more of the maximum structural stiffness, the minimum temperature standard deviation, the minimum volume fraction value, the minimum weighted strain energy, and the minimum flexibility index;

[0104] The constraint conditions include one or more of the modal frequency constraint, the deformation value constraint of different components, the mass fraction constraint, the draft constraint, and the minimum member size constraint.

[0105] Design response metrics can include one or more of the following: deformation values, modal frequency values, compliance index, temperature values, volume fraction values, and mass information for each component in the supporting structure. Deformation values ​​refer to the displacement of key nodes on the model under load. Modal frequency values ​​are the natural frequencies obtained from structural dynamics analysis. The weighted strain energy or compliance index is a comprehensive index calculated based on weighted values ​​and corresponding compliance for each operating condition, comprehensively reflecting the overall structural flexibility under multiple conditions. Compliance is the reciprocal of stiffness. Temperature values ​​are the nodal temperatures obtained from thermal analysis. Volume fraction values ​​and mass information are directly related to the degree of lightweighting of the structure.

[0106] The objective functions include maximizing structural stiffness, minimizing temperature standard deviation, minimizing volume fraction, minimizing weighted strain energy, and minimizing compliance index.

[0107] Among these objectives, maximizing structural stiffness refers to minimizing structural strain energy or minimizing the compliance index; minimizing the temperature standard deviation aims to achieve a more uniform temperature distribution and reduce differences in thermal deformation; minimizing the volume fraction value minimizes the weight of the machine tool support structure; minimizing the weighted strain energy minimizes the weighted values ​​for different operating conditions; and minimizing the compliance index. During the design process, one or more of these objectives can be selected and combined to form a multi-objective optimization problem.

[0108] The constraints specifically include: modal frequency constraints, such as requiring the first-order modal frequency to be greater than a certain safety value; deformation value constraints for different components, such as requiring the displacement of the tool tip under the maximum cutting force to be less than a certain allowable accuracy value; mass fraction constraints, such as requiring the total mass after optimization to not exceed a specific percentage of the initial mass; and one or more of the following: draft constraints and minimum member size constraints. Draft constraints and minimum member size constraints are manufacturability constraints. Draft constraints ensure that the optimized result has a draft angle suitable for casting, while minimum member size constraints prevent structures that are too thin to be manufactured.

[0109] The design method for machine tool support structures provided by this invention, through multiple quantifiable design responses, objective functions, and constraint options closely related to machine tool performance and manufacturing processes, enables designers to define and optimize the design process with great flexibility and precision according to actual needs. This greatly enhances the practicality and relevance of the design method, effectively solving complex, multi-objective engineering designs.

[0110] In one embodiment, the weight value for any operating condition is determined based on the ratio of the machine tool stiffness value under the current operating condition to the sum of the machine tool stiffness values ​​under all operating conditions.

[0111] For example, assuming n operating conditions are considered, the comprehensive stiffness value of each condition is obtained through analysis The weight value corresponding to the i-th condition can be calculated by the following formula: .

[0112] Among all the analyzed conditions, the condition with higher stiffness value is also assigned a higher weight value. This means that in the optimization process, the condition with better stiffness performance will be subject to more collaborative optimization. The advantage performance area of the structure can be enhanced.

[0113] In one embodiment, the finite element model of the support structure of the machine tool is constructed, comprising:

[0114] The internal rib plate of the support structure is filled as a solid to construct a rib-free frame of the support structure;

[0115] The stiffness parameters of the machine tool foot joint, the screw joint parameters between the machine tool support structure components, and the material parameters of the support structure are defined in the rib-free frame to obtain the finite element model of the support structure.

[0116] Specifically, in the three-dimensional modeling software, the internal space of the hollow casting such as the bed and the column is completely filled to form a solid body with only an external contour, i.e. a rib-free frame. This can provide the maximum designable domain for the subsequent optimization algorithm, so that the algorithm can not be limited by any preset rib form and find the optimal force transmission path.

[0117] The stiffness parameters of the machine tool foot joint, the screw joint parameters between the machine tool support structure components, and the material parameters of the support structure are defined in the rib-free frame to obtain the finite element model of the support structure. On the basis of the solid body model, various connection and material properties are defined.

[0118] The stiffness parameters of the machine tool foot joint are used to simulate the connection characteristics between the machine tool base and the ground. The screw joint parameters are used to simulate the mechanical properties of the area connected by screws between components, such as the joint surface of the bed and the column. The material parameters include the elastic modulus, Poisson's ratio, density, thermal conductivity, etc. of the casting material. Through accurate parameters, the finite element model constructed can obtain accurate results in subsequent analysis.

[0119] In one embodiment, the stiffness parameters of the machine tool foot joint are determined based on the normal stiffness and tangential stiffness of the machine tool foot joint;

[0120] The screw joint parameters are determined based on the screw parameter information and the number of screws between the components of the support structure.

[0121] It should be noted that the foot joint, as the interface between the machine tool and the foundation, exhibits three-dimensional mechanical behavior. Therefore, it needs to be decomposed into two mutually perpendicular components. Normal stiffness refers to the foot's ability to resist compressive or tensile deformation in a direction perpendicular to the foundation. Tangential stiffness refers to the foot's ability to resist shear or horizontal slip deformation in a plane parallel to the foundation.

[0122] Normal and tangential stiffness can be obtained through physical experiments. For example, by fabricating foundation and anchor specimens, applying loads using equipment such as tensile and compressive testing machines, and measuring displacements, a load-displacement curve can be obtained, the slope of which represents the stiffness. Experiments can be conducted separately in the normal and tangential directions to obtain their respective stiffness values ​​or stiffness curves.

[0123] The stiffness value per unit area of ​​the anchor joint is obtained by dividing the obtained stiffness value by the nominal area of ​​the anchor and the foundation.

[0124] It should be noted that the support methods for the anchor joint include rigid support and elastic support. Elastic support at the anchor joint involves the anchor being floating on the foundation, such as... Figure 9 The schematic diagram of the locking connection between the foot and the foundation provided by this invention shows that the rigid support of the foot joint is achieved by locking the bed, foot, and foundation specimen together with foot bolts. Figure 10 The schematic diagram of the elastic connection between the anchor and the foundation provided by this invention shows that the elastic support anchor is connected to the foundation specimen. The stiffness of the elastic support anchor is obtained through a tensile and compression testing machine, etc.; the stiffness of the rigid support anchor is obtained through modal testing, and the locking torque of the rigid support anchor is applied according to the torque given by the machine tool assembly. The variation curve of the normal vector stiffness value of the obtained support anchor can be shown as follows. Figure 11 The schematic diagram of the variation curve of the normal vector stiffness value of the support footing provided by this invention is shown. Wherein, the horizontal axis represents the contact pressure, and the vertical axis represents the stiffness value. The obtained variation curve of the tangential vector stiffness value of the support footing can be seen as follows... Figure 12 The schematic diagram of the variation curve of the tangential stiffness value of the supporting foot provided by this invention is shown. The horizontal axis represents the contact pressure, and the vertical axis represents the stiffness value.

[0125] The screw joint parameters are determined based on the screw parameter information and the number of screws between the components of the support structure.

[0126] Specifically, such as Figure 13The screw joint parameter determination process provided by the application is shown in the schematic diagram, and the material characteristic parameters of the screw joints between the support structure members of the machine tool are determined according to the screw specifications, the number of screws and other parameters of the screw joints of the machine tool. The screw joint parameters also include the machining accuracy of the joint surface, the assembly process and the like; the number and specifications of the screw joints are used to determine the total contact pressure of the screw joints; the elastic modulus, the tangential modulus and the Poisson's ratio parameters of the screw joints can be obtained based on the Yoshimura method; and the density, the thermal conductivity and the like of the screw joints are obtained through the materials of the connected members.

[0127] In one embodiment, the optimization design of the design region in the finite element model is performed based on the design response index, the objective function and the constraint condition, and the design result of the support structure member is determined, including:

[0128] The optimization design of the design region in the finite element model is performed based on the design response index, the objective function and the constraint condition, and the layout of the rib plate, the layout of the foot, the number of the foot and the layout of the screw joint in the support structure member are determined.

[0129] Based on the optimization target and the constraint, a topology optimization algorithm is performed on the design region containing each component and joint in the finite element model, and the final optimization result can determine the layout of the rib plate, the layout of the foot, the number of the foot and the layout of the screw joint in the support structure member.

[0130] It can be understood that, since the load borne by the machine tool needs to be transmitted to the support through the rib plate and the joint, and finally transmitted to the foundation, the rib plate distribution of each structure member, the layout of the screw joint between the structure members, the layout and number of the support foot between the bed body and the foundation are interdependent, and only when the structural rib plate layout, the layout of the screw joint, the position and number of the foot are collaboratively optimized, the comprehensive performance of the structure can be further improved, and the accuracy maintenance, reliability and stability during the working process of the numerical control machine tool can be ensured.

[0131] The layout of the rib plate determines the optimal position, shape and connection mode of the internal reinforcing ribs of the bed body and the column. The layout of the foot determines which positions on the machine tool base the foot should be installed to most effectively transmit the load to the foundation and provide the best support. The number of the foot determines the minimum number of the foot required to achieve the optimal support, which helps to control the cost. The layout of the screw joint determines how the material should be distributed at the connecting surface of the component to most efficiently transmit the screw pretightening force and the working load, which provides a basis for the determination of the screw position and the design of the connecting surface. The change of the performance index after optimization can be as follows Figure 14 The change of the performance index after optimization provided by the application is shown in the schematic diagram, and the weight of the support structure member is reduced, the static stiffness is improved, the thermal stiffness is improved and the dynamic stiffness is improved after optimization.

[0132] The machine tool whole machine support structure part collaborative topology optimization design method in the application fully considers the mutual influence between the foot joint, the screw joint and the key support part, effectively avoids the generation of stiffness redundancy or insufficient phenomenon caused by optimization of a single part in the related method, comprehensively considers the influence of machine tool dynamic and static thermal stiffness on the topology optimization analysis working condition and reasonably distributes the weight, can realize the optimization of the bed body, beam rib plate layout, number and sand hole position at one time, can also realize the optimization of the layout, number of foot and the layout of screw joint screw, can better obtain the transmission route of force to the constraint action position load, greatly saves the machine tool optimization design time and improves the design efficiency.

[0133] The optimization result of the machine tool key support part collaborative topology optimization design method can obtain more reasonable support position, more optimal rib distribution form and screw joint layout, reduce the cost of machining the contact area of the screw joint, realize more optimal structure performance, one-time design can achieve the machining precision meeting the use requirement, effectively avoid the repeated version iteration in the later stage, reduce the blindness of design, greatly improve the efficiency of machine tool design, and provide effective scientific theory data support for machine tool whole machine optimization design.

[0134] The machine tool support structure part design device provided by the application is described below, and the machine tool support structure part design device described below can be correspondingly referred to the machine tool support structure part design method described above.

[0135] As shown in Figure 15 The device comprises:

[0136] The model construction module 1510 is configured to construct a finite element model of a support structure part of a machine tool and define a design region in the finite element model; the design region comprises components of the support structure part and component joints;

[0137] The weight calculation module 1520 is configured to determine a weight value of the machine tool in each running working condition based on pose change information of a moving component in the machine tool in each running working condition;

[0138] The design module 1530 is configured to determine a design response index, an objective function and a constraint condition of the support structure part based on the weight value and a design requirement index of the support structure part;

[0139] The design result determination module 1540 is configured to perform optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determine a design result of the support structure part.

[0140] The machine tool support structure design device provided by the application can obtain a globally optimal support structure from the initial stage of design, fundamentally solve the defects of stiffness mismatch between structures caused by separate design, ensure the stiffness matching between structures after optimization design, and significantly improve the design accuracy of the machine tool support structure and the overall performance of the machine.

[0141] In one embodiment, the weight calculation module 1520 is specifically configured to:

[0142] The weight value of the machine tool in each operating condition is determined based on the position change information of the moving part in the machine tool in each operating condition, and includes:

[0143] The stiffness value of the machine tool in each operating condition is determined based on the position change information of the moving part in each operating condition; the stiffness value includes dynamic stiffness value, static stiffness value and thermal stiffness value;

[0144] The weight value of each operating condition is determined based on the stiffness value of the machine tool in each operating condition.

[0145] In one embodiment, the design module 1530 is specifically configured to:

[0146] The design response index includes one or more of the deformation value, modal frequency value, flexibility index, temperature value, volume fraction value and mass information of each component in the support structure; the flexibility index is determined by the weight value of each operating condition;

[0147] The objective function includes one or more of the maximum structural stiffness, minimum temperature standard deviation, minimum volume fraction value, minimum weighted strain energy and minimum flexibility index;

[0148] The constraint condition includes one or more of the modal frequency constraint, deformation value constraint of different components, mass fraction constraint, ejection constraint and minimum member size constraint.

[0149] In one embodiment, the weight calculation module 1520 is further specifically configured to:

[0150] The weight value of any operating condition is determined based on the ratio of the machine tool stiffness value in the current condition to the sum of the machine tool stiffness values in all conditions.

[0151] In one embodiment, the model construction module 1510 is specifically configured to:

[0152] constructing a finite element model of the support structure of the machine tool, comprising:

[0153] filling the internal rib plates of the support structure as a solid to construct a rib-free frame of the support structure;

[0154] defining a rigidity parameter of a machine tool foot joint, a screw joint parameter between support structure components of the machine tool, and a material parameter of the support structure in the rib-free frame to obtain the finite element model of the support structure.

[0155] In one embodiment, the model construction module 1510 is specifically configured to:

[0156] The rigidity parameter of the machine tool foot joint is determined based on the normal rigidity and tangential rigidity of the machine tool foot joint;

[0157] The screw joint parameter is determined based on the screw parameter information and the number of screws between the components of the support structure.

[0158] In one embodiment, the design result determination module 1540 is specifically configured to:

[0159] Based on the design response index, the objective function and the constraint condition, the optimization design of the design area in the finite element model is performed to determine the design result of the support structure, comprising:

[0160] Based on the design response index, the objective function and the constraint condition, the optimization design of the design area in the finite element model is performed to determine the rib layout, the foot layout, the number of feet and the screw joint layout in the support structure.

[0161] Figure 16 An example of a schematic diagram of a physical structure of an electronic device is shown in Figure 16 As shown, the electronic device can include a processor (processor) 1610, a communications interface (Communications Interface) 1620, a memory (memory) 1630 and a communication bus 1640, wherein the processor 1610, the communications interface 1620, the memory 1630 complete the communication between each other through the communication bus 1640. The processor 1610 can call the logic instructions in the memory 1630 to execute the design method of the machine tool support structure, which comprises: constructing a finite element model of the support structure of the machine tool, and defining a design area in the finite element model; the design area includes components and component joints of the support structure;

[0162] Based on the position change information of the moving components in the machine tool under each operating condition, the weight value of the machine tool under each operating condition is determined;

[0163] determine a design response index, an objective function and a constraint condition of the support structure based on the weight value and a design requirement index of the support structure;

[0164] perform optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determine a design result of the support structure.

[0165] Further, the logic instructions in the memory 1630 described above can be implemented in the form of a software function unit and sold or used as an independent product, which can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the parts that make contributions to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0166] On the other hand, the present application also provides a computer program product, which comprises a computer program, the computer program can be stored on a non-transitory computer readable storage medium, and the computer program is executed by a processor, so that the computer can execute the design method of the machine tool support structure provided by the above-mentioned methods, which comprises: constructing a finite element model of a support structure of a machine tool, and defining a design region in the finite element model; the design region includes components of the support structure and component joints;

[0167] determine a weight value of the machine tool in each operating condition based on the pose change information of the moving components in the machine tool in each operating condition;

[0168] determine a design response index, an objective function and a constraint condition of the support structure based on the weight value and a design requirement index of the support structure;

[0169] perform optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determine a design result of the support structure.

[0170] In yet another aspect, the present application also provides a non-transitory computer readable storage medium having stored thereon a computer program, which, when executed by a processor, implements a method for designing a machine tool support structure as provided by any of the above methods, the method comprising: constructing a finite element model of a support structure of a machine tool, and defining a design region in the finite element model; the design region comprising components of the support structure and component junctions;

[0171] determining a weight value of the machine tool in each operating condition based on the pose change information of the moving components in the machine tool in each operating condition;

[0172] determining a design response index, an objective function and a constraint condition of the support structure based on the weight value and a design requirement index of the support structure;

[0173] performing an optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determining a design result of the support structure.

[0174] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0175] From the above description of the embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software plus necessary general hardware platforms, and of course can also be realized by hardware. Based on such understanding, the above technical solutions, essentially or in terms of the contribution to the prior art, can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0176] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of designing a machine tool support structure member, characterized by, The method comprises the following steps: constructing a finite element model of a support structure of a machine tool and defining a design region in the finite element model; the design region comprises components of the support structure and component junctions; the component junctions comprise screw junctions and foot junctions; determining stiffness values of the machine tool in each operating condition based on pose change information of a moving component in the machine tool in each operating condition; the stiffness values comprise dynamic stiffness values, static stiffness values and thermal stiffness values; determining weight values in each operating condition based on the stiffness values of the machine tool in each operating condition; the weight value in any operating condition is determined based on the ratio of the machine tool stiffness value in the current operating condition to the sum of the machine tool stiffness values in all operating conditions; determining design response indicators, objective functions and constraint conditions of the support structure based on the weight values and design requirement indicators of the support structure; performing collaborative optimization design of the design region in the finite element model based on the design response indicators, objective functions and constraint conditions to determine the design result of the support structure.

2. The method of designing a machine tool support structure member according to claim 1, wherein The design response indicators comprise one or more of deformation values, modal frequency values, flexibility indices, temperature values, volume fraction values and mass information of components in the support structure; the flexibility index is determined based on the weight values in each operating condition; The objective functions comprise one or more of maximum structural stiffness, minimum temperature standard deviation, minimum volume fraction value, minimum weighted strain energy and minimum flexibility index; The constraint conditions comprise one or more of modal frequency constraints, deformation value constraints of different components, mass fraction constraints, draft constraints and minimum member size constraints.

3. The method of designing a machine tool support structure member according to claim 1, wherein The method of constructing a finite element model of a support structure of a machine tool comprises the following steps: filling internal rib plates of the support structure as entities to construct a rib-free frame of the support structure; defining stiffness parameters of machine tool foot junctions, screw junction parameters between machine tool support structures and material parameters of the support structure in the rib-free frame to obtain the finite element model of the support structure.

4. The method of designing a machine tool support structure member according to claim 3, wherein The stiffness parameters of the machine tool foot junctions are determined based on the normal stiffness and tangential stiffness of the machine tool foot junctions; The screw junction parameters are determined based on screw parameter information and the number of screws between components of the support structure.

5. The method of designing a machine tool support structure member according to claim 1, wherein The method of performing optimization design of the design region in the finite element model based on the design response indicators, objective functions and constraint conditions to determine the design result of the support structure comprises the following steps: performing optimization design of the design region in the finite element model based on the design response indicators, objective functions and constraint conditions to determine the rib layout, foot layout, number of feet and screw junction layout in the support structure.

6. A design device for a machine tool support structure, characterized in that, The method comprises the following steps: a model construction module for constructing a finite element model of a support structure of a machine tool and defining a design region in the finite element model; the design region comprises components of the support structure and component junctions; the component junctions comprise screw junctions and foot junctions; A weight calculation module is configured to determine a rigidity value of the machine tool in each operating condition based on the pose change information of the moving part in each operating condition; the rigidity value includes a dynamic rigidity value, a static rigidity value and a thermal rigidity value; The weight value in each operating condition is determined based on the rigidity value of the machine tool in each operating condition; the weight value in any operating condition is determined based on the ratio of the rigidity value of the machine tool in the current operating condition to the sum of the rigidity values of the machine tool in all operating conditions; A design module is configured to determine a design response index, an objective function and a constraint condition of the support structure based on the weight value and a design requirement index of the support structure; A design result determination module is configured to perform a collaborative optimization design of the design region in the finite element model based on the design response index, the objective function and the constraint condition, and determine a design result of the support structure.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and running on the processor, characterized in that, The processor executes the computer program to implement the design method of the machine tool support structure according to any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the design method of the machine tool support structure according to any one of claims 1 to 5.

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