Numerical control machine tool synchronous evolution control method and system associated with dynamic and static errors

Abstract

The invention discloses a numerical control machine tool synchronous evolution control method and system associated with dynamic and static errors, relates to the technical field of information processing management, and is used for solving the problem that a machine tool structure optimization method is poor in structural integrity, structural connectivity and dynamic response characteristic analysis. By monitoring and analyzing geometric structure parameter changes of all parts in the machine tool operation process, effective geometric structure parameters with the high influence degree are screened out, preliminary optimization is carried out, a geometric structure optimization evaluation model is established, and an optimization result is evaluated; the method comprises the following steps of: acquiring local rigidity and weight, establishing an optimization evaluation model, defining geometric structure parameters of a plurality of components as an integral assembly structure, constructing a parallel optimization model by utilizing a grid division and rigidity matrix calculation method, and finally obtaining optimization results of a macroscopic unit and a connecting unit by taking minimization of structural flexibility as a target. Key parameters can be accurately monitored and optimized, the structural connectivity is considered, and the overall performance and stability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of CNC machine tool control, and in particular to a method and system for synchronous evolution control of CNC machine tools with correlated dynamic and static errors. Background Art

[0002] In modern manufacturing, CNC machine tools have become important processing equipment due to their high precision and high efficiency. However, due to the complexity of the mechanical structure and the influence of the external environment, machine tools often accumulate a certain amount of geometric deformation during operation, which has a certain impact on machining accuracy. In addition, the dynamic response of the machine tool can also affect the machining results. These effects become more significant in high-speed machining and complex surface machining. To address these problems, various methods based on dynamic error compensation and static error correction have been proposed. However, these methods often lack comprehensive consideration of the systematic, dynamic, and structural dependence of geometric deformation.

[0003] Specifically, traditional optimization methods often only improve the static characteristics of a certain component of the machine tool, ignoring the integrity and dynamic response characteristics of the structure. The optimization method based on the overall assembly structure can take into account the interaction, connection relationship and overall behavior between the various components when analyzing the deformation of the geometric structure, thereby more accurately evaluating and optimizing the dynamic performance of the machine tool. This technical solution monitors and analyzes the geometric deformation of each component of the machine tool in real time, and on this basis optimizes the local stiffness and weight, and finally constructs an optimization model for the overall assembly structure. This optimization model not only takes into account the geometric parameters of the static structure, but also can dynamically adjust the parameters of each unit to achieve structural optimization based on connection units and macro units, thereby significantly improving the overall performance and working accuracy of the machine tool. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, a synchronous evolutionary control method for CNC machine tools with correlated dynamic and static errors is proposed. By hierarchically optimizing the structure of the machine tool, the rigidity is enhanced from local to overall, and a division method based on connection units and macro units is adopted to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a synchronous evolution control method for CNC machine tools with associated dynamic and static errors, comprising: equating the structural parameters corresponding to each component and the connection relationship between the components to an overall assembly structure, and dividing the overall assembly structure into grids according to a preset grid size to obtain macro units and connection units; The unit stiffness matrix and the connection stiffness matrix are obtained by processing the macro unit and the connection unit respectively, and then the combined stiffness matrix is ​​obtained according to the unit stiffness matrix and the connection stiffness matrix; Based on the combined stiffness matrix, a parallel optimization model is established with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and selection optimization algorithm to obtain the optimization results of the macro unit and the connection unit.

[0006] In a preferred embodiment, the grid division method is to grid the overall assembly structure of the machine tool according to the grid size preset by the system and the type of each component of the machine tool and the connection method of each component, to obtain multiple discrete grid units, forming macro units representing each component and connection units representing the actual connection status of the components.

[0007] In a preferred embodiment, the expressions of the element stiffness matrix and the connection stiffness matrix are: Each macro unit The element stiffness matrix expression of The calculation process is: ; Where, represents the density design variable of each macro unit, The element stiffness matrix used to identify each macro element, is the penalty factor, represents the transpose symbol of the matrix, represents the geometric matrix, is the elastic matrix of the material. The above matrices can be calculated by finite element analysis based on the relevant parameters of the corresponding macro units. represents the volume of the integral differential element; Each connection unit The connection stiffness matrix expression is for: Where, Identify the connection stiffness matrix of each connection element, , is the design variable of connection stiffness, and Represents the stiffness matrix in different directions and They represent the number of nodes of the corresponding stiffness matrix.

[0008] In a preferred embodiment, the expression formula of the combined stiffness matrix is: Based on the stiffness matrix of the macro unit and the connection unit, the contribution of each unit is accumulated to the corresponding position of the global matrix to obtain the combined stiffness matrix ; Based on the structural mechanics behavior, the stiffness matrix of the macro unit and the connection unit is processed to obtain ; Where is defined as the initial stiffness matrix of the macro unit; Defined as the initial stiffness matrix of the connection element; then combined with the stiffness matrix .

[0009] In a preferred embodiment, a parallel optimization model is established with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints: ; ; ; ; ; in, represents the objective function, represents the structural flexibility, is the transposition symbol, represents the force balance equation, is the volume constraint, represents the maximum value of the total volume of the macro unit, is the connection stiffness constraint, represents the maximum value of the total stiffness of the connection element, represents the density design variable of each macro unit, Indicates that the stiffness of the connection element is non-negative, is the displacement vector, and by solving the equilibrium equation get.

[0010] In a preferred embodiment, the sensitivity analysis is specifically: Calculate the sensitivity corresponding to the macro unit density and the connection unit stiffness respectively; The sensitivity of the macro-cell density is: ; where a represents the penalty factor, represents the transpose of the corresponding displacement component of the macro unit, represents the corresponding displacement component of the macro unit; The sensitivity of the link element stiffness is: Where, represents the transpose of the displacement component corresponding to the connection unit, is the displacement component corresponding to the connection element.

[0011] In a preferred embodiment, before the structural parameters corresponding to each component and the connection relationship between the components are equated to the overall assembly structure, the overall assembly structure is meshed according to a preset mesh size to obtain the macro units and the connection units, the following steps are also included, in which the structural parameters corresponding to each component are geometric structure parameters; a. Monitor and compile statistics on the geometric parameters of each component during machine tool operation, obtain the change in the geometric parameters and their corresponding deformation values, and determine the degree of influence through comparison. Compare and analyze the degree of influence, and screen a valid set of geometric parameters based on the comparison results. Preliminary optimization of the component geometry is then performed to obtain the initial geometric optimization results. b. Based on the initial geometry optimization results, obtain the local stiffness and weight of each component, establish a geometry optimization result evaluation model, and obtain the geometry optimization evaluation results.

[0012] In a preferred embodiment, multiple geometric parameters corresponding to various components of the machine tool are measured during the operation cycle to form a set of geometric parameters corresponding to each component. ;in, Representative components, x represents the number of geometric parameter sets, is the set of geometric parameters of the component, , m represents the number of geometric structure parameters of the component, i is the index variable, and the displacement of each component of the machine tool during operation is measured using strain gauges and displacement sensors. The relationship between the geometric structure parameters and the deformation is represented by mapping ; Where B is the quantity between the geometric structure parameter and the deformation, Representation components No. geometric parameters, Representation components The geometric structure parameter values ​​in And its corresponding deformation value ;j is the index variable; The geometric structure parameter values ​​are obtained through experimental measurement The change in value , measure again to obtain the new deformation of the component after the geometric structure parameters are changed , the new deformation With the original deformation Calculate the difference ;

[0013] The geometric structure parameter changes Deformation difference Calculate the ratio to get the degree of influence ; The degree of impact With preset threshold Make comparisons; The degree of impact Greater than the preset threshold The geometric parameters of the components are screened as the geometric parameters that affect the stiffness change of the corresponding components; traverse each component All geometric parameter values Collect and organize the geometric structure parameters that meet the condition of being greater than the threshold value to form a valid geometric structure parameter set; The effective geometric structure parameters corresponding to each component are selected as design variables, and a mathematical model for component geometric structure optimization is established. The geometric structure parameters of each component of the machine tool are optimized to obtain the initial geometric structure optimization results.

[0014] In a preferred embodiment, a geometry optimization result evaluation model is established, and the geometry optimization evaluation result is obtained as follows: Calculate C to represent the optimization result evaluation index and Where, Respectively represent The local stiffness and weight of each component, Respectively represent target stiffness and target weight of each component, is the weight coefficient of stiffness deviation, is the weight coefficient of weight deviation; Based on the local stiffness and weight of each component, a geometric structure optimization result evaluation model is established. ; Its corresponding mathematical expression is ;in, is the indicator threshold; When the comprehensive index When it is less than or equal to the index threshold, it means that the initial geometric structure optimization meets the optimization requirements; When the comprehensive index When it is greater than the indicator threshold, the requirement is not met.

[0015] A synchronous evolutionary control system for CNC machine tools that correlates dynamic and static errors, including: a geometric structure monitoring and optimization module, an optimization result evaluation module, an assembly structure meshing module, a stiffness matrix calculation module, and a parallel model solving module; The geometry monitoring and optimization module is used to monitor and count the geometry parameters of each component during the operation of the machine tool, obtain the change value of the geometry parameters and their corresponding deformation value, and obtain the degree of influence through comparison. The degree of influence is compared and analyzed, and a set of effective geometry parameters is screened based on the comparison results. The geometry of the component is preliminarily optimized to obtain the initial geometry optimization result. The optimization result evaluation module is used to obtain the local stiffness and weight of each component according to the initial geometric structure optimization results, establish a geometric structure optimization result evaluation model, and obtain the geometric structure optimization evaluation results; The assembly structure meshing module is used to equate the effective geometric structure parameters corresponding to each component and the connection relationship between each component to the overall assembly structure based on the geometric structure optimization evaluation results. The overall assembly structure is meshed according to the preset grid size to obtain macro units and connection units. The stiffness matrix calculation module is used to obtain the unit stiffness matrix and the connection stiffness matrix by processing the macro unit and the connection unit, and then obtain the combined stiffness matrix according to the unit stiffness matrix and the connection stiffness matrix; The parallel model solving module is used to establish a parallel optimization model based on the combined stiffness matrix, with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and selection optimization algorithms to obtain the optimization results of the macro unit and the connection unit.

[0016] The technical effects and advantages of the present invention are as follows: 1. The present invention first monitors the geometric parameters of machine tool components, analyzes the degree of influence, selects effective geometric structure parameters, and preliminarily optimizes them to obtain initial results. Based on this, local stiffness and weight are obtained, and an evaluation model is established to obtain evaluation results. This not only accurately monitors and optimizes the key geometric structure parameters of CNC machine tools, but also ensures the maximization of optimization effects through a scientific evaluation model, providing a scientific basis for subsequent geometric structure optimization and ensuring the sustainability and effectiveness of optimization. 2. Through geometric structure optimization evaluation, the effective geometric parameters and connection relationships of each component of the CNC machine tool are equivalent to the overall assembly structure, and the grid is divided according to the preset grid size to form macro units and connection units; the corresponding stiffness matrix is ​​obtained by processing these units, and further integrated into a combined stiffness matrix; then a parallel optimization model is established with the goal of minimizing structural flexibility and is limited by the total volume of the macro unit and the total stiffness of the connection unit. The model is solved using sensitivity analysis and selection optimization algorithms to obtain the optimization results of the macro unit and the connection unit, which significantly improves the dynamic and static performance of the CNC machine tool. By effectively processing the connection relationship between the components, the error is reduced, the working accuracy and stability of the machine tool are improved, and the efficient collaborative control of the CNC machine tool in a complex working environment is realized, thereby improving the overall processing accuracy and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the overall structural block diagram of the synchronous evolution control method for CNC machine tools with associated dynamic and static errors proposed by the present invention; Figure 2 This is a structural block diagram of the synchronous evolution control system for CNC machine tools with associated dynamic and static errors proposed by the present invention. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0019] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0020] Reference Figure 1-Figure 2 , the synchronous evolution control method of CNC machine tools with correlated dynamic and static errors, the specific operation process is as follows: Step 1: Monitor and count the geometric parameters of each component during the operation of the machine tool, obtain the change value of the geometric parameters and their corresponding deformation value, and obtain the degree of influence through comparison. Compare and analyze the degree of influence, and screen the effective geometric parameter set based on the comparison results. Then, preliminarily optimize the component geometry to obtain the initial geometry optimization result; including: In this embodiment, the geometric structure parameters include but are not limited to: Directly measure multiple geometric parameters corresponding to each component of the machine tool during the operation cycle through experimental equipment to form a set of geometric parameters corresponding to each component ;in, Representative components, x represents the number of geometric parameter sets, is the set of geometric parameters of the component, , m represents the number of geometric structure parameters of the component, i is the index variable, and the displacement of each component of the machine tool during operation is measured using strain gauges and displacement sensors. The relationship between the geometric structure parameters and the deformation is represented by mapping ; Where B is the quantity between the geometric structure parameter and the deformation, Representation components No. geometric parameters, Representation components The geometric structure parameter values ​​in And its corresponding deformation value ;j is the index variable; The geometric structure parameter values ​​are obtained through experimental measurement The change in value , measure again to obtain the new deformation of the component after the geometric structure parameters are changed , the new deformation With the original deformation Calculate the difference ;

[0021] The geometric structure parameter changes Deformation difference Calculate the ratio to get the degree of influence ; The degree of impact With preset threshold Make comparisons; The degree of impact Greater than the preset threshold The geometric parameters of the components are screened as the geometric parameters that affect the stiffness change of the corresponding components; traverse each component All geometric parameter values Collect and organize the geometric structure parameters that meet the condition of being greater than the threshold value to form a valid geometric structure parameter set; The effective geometric structure parameters corresponding to each component are selected as design variables, and a mathematical model for component geometric structure optimization is established. The geometric structure parameters of each component of the machine tool are optimized to obtain the initial geometric structure optimization results.

[0022] Step 2: Obtain the local stiffness and weight of each component based on the initial geometry optimization results, establish a geometry optimization result evaluation model, and obtain the geometry optimization evaluation results; After optimizing the geometric structure of each component, the local stiffness and weight of each component of the machine tool are measured and obtained; Based on the local stiffness and weight of each component, a geometric structure optimization result evaluation model is established. ; Its corresponding mathematical expression is ;in, is the indicator threshold; When the comprehensive index When it is less than or equal to the index threshold, it means that the geometric structure optimization meets the optimization requirements, that is, the stiffness and weight are balanced; When the comprehensive index When it is greater than the indicator threshold, the requirement is not met; It should be noted that represents the evaluation index of single-scale optimization results and Where, Respectively represent The local stiffness and weight of each component, Respectively represent The target stiffness and target weight of each component are determined by the design requirements and historical design experience of professionals. is the weight coefficient of stiffness deviation, is the weight coefficient of weight deviation, The threshold value for evaluating the balance between stiffness and weight of each component is determined based on a large amount of experimental data, experience, and the specific performance requirements of the machine tool; It should be noted that the balance between stiffness and weight are the two main objectives that need to be considered in structural optimization problems. The above formula determines whether the local structural optimization of the component geometry meets the requirements by evaluating the balance between stiffness and weight of each component.

[0023] In this embodiment, the results of optimizing the structural parameters of machine tool components using a single scale using existing technologies are evaluated to determine whether the optimization scheme meets the design requirements. This not only enables the neural model to quickly and accurately predict the stiffness performance of components under different structural parameter combinations, but also provides an analytical basis and data support for subsequent multi-scale analysis.

[0024] Step 3: Based on the geometric structure optimization evaluation results, the effective geometric structure parameters corresponding to each component and the connection relationship between each component are equated to the overall assembly structure. The overall assembly structure is meshed according to the preset grid size to obtain macro units and connection units; including: The preset grid size is set based on the requirements of specific components; the preset grid size is used to indicate the degree of grid detail; according to the preset grid size, the overall assembly structure of the machine tool is gridded according to the types of machine tool components and the connection methods of the components, resulting in multiple discrete grid cells, forming macro cells and connection cells; A grid cell represents a macro unit, and a macro unit represents a machine tool component. Furthermore, the contact surfaces and target surfaces between components are determined based on their actual connection conditions and defined as contact pairs. For example, when a machine tool guide rail and slider are connected, the guide rail surface is set as the target surface, and the slider surface is set as the contact surface. This allows for accurate simulation of the mechanical behavior of the connection. Repeating this operation yields multiple contact pairs in the overall assembly structure and defines them as connection units. It should be noted that, in this embodiment, the connecting unit is composed of at least two macro units, that is, the connecting unit serves as a macro unit.

[0025] Step 4: Obtain the unit stiffness matrix and the connection stiffness matrix by processing the macro unit and the connection unit, and then obtain the combined stiffness matrix based on the unit stiffness matrix and the connection stiffness matrix; Specifically, each macro unit The element stiffness matrix expression of The calculation process is: ; Where, represents the density design variable of each macro unit, The element stiffness matrix used to identify each macro element, is the penalty factor, represents the transpose symbol of the matrix, represents the geometric matrix, is the elastic matrix of the material. The above matrices can be calculated by finite element analysis based on the relevant parameters of the corresponding macro units. represents the volume of the integral differential element; In this embodiment, a contact pair is defined as a connection unit, that is, the stiffness matrix of the connection unit is determined by the contact mechanical behavior between each contact pair; Each connection unit The connection stiffness matrix expression is for: Where, Identify the connection stiffness matrix of each connection element, , is the design variable of connection stiffness, and Represents the stiffness matrix in different directions and , They represent the number of nodes of the corresponding stiffness matrix respectively; Based on the stiffness matrix of the macro unit and the connection unit, the contribution of each unit is accumulated to the corresponding position of the global matrix to obtain the combined stiffness matrix ; Based on the structural mechanics behavior, the stiffness matrix of the macro unit and the connection unit is processed to obtain ; Where is defined as the initial stiffness matrix of the macro unit; Defined as the initial stiffness matrix of the connection element; Combined with the stiffness matrix .

[0026] Step 5: Based on the combined stiffness matrix, a parallel optimization model is established with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and a selection optimization algorithm to obtain the optimization results of the macro unit and the connection unit. Assume the objective function is , the constraint functions are , then the parallel optimization model is expressed as: ; ; ; ; ; in, represents the objective function, represents the structural flexibility, is the transposition symbol, represents the force balance equation, is the volume constraint, represents the maximum value of the total volume of the macro unit, is the connection stiffness constraint, represents the maximum value of the total stiffness of the connection element, represents the density design variable of each macro unit, Indicates that the stiffness of the connection element is non-negative, is the displacement vector, and by solving the equilibrium equation get; Calculate the sensitivity corresponding to the macro unit density and the connection unit stiffness respectively; The sensitivity of the macro-cell density is: ; In the formula, a represents the penalty factor, represents the transpose of the corresponding displacement component of the macro unit, represents the corresponding displacement component of the macro unit; The sensitivity of the link element stiffness is: Where, represents the transpose of the displacement component corresponding to the connection unit, is the displacement component corresponding to the connection unit; Using gradient-based algorithms such as MMA (Moving Asymptotes) or SQP (Sequential Quadratic Programming) to iteratively update the macro-element density and link element stiffness, the gradient-based algorithm uses the sensitivity of the objective function to the macro-element density and link element stiffness, and proceeds in the direction that can reduce the objective function value, gradually approaching the optimal solution to obtain the final optimized structure; For example, when optimizing the components of a machine tool, the final optimization results include structural shape and material distribution: after optimization, the structural shape of the bed is no longer a regular rectangular parallelepiped, and some reasonable hollow areas appear inside, with the material mainly distributed in areas subject to greater stress; for example, in areas subject to cutting forces, the macro unit density is higher and the material is denser; connection part optimization: the connection unit stiffness of components such as the bed and columns is reasonably adjusted; the contact area of ​​the connection is increased or the connection method is changed, so that the total connection stiffness meets the constraint conditions while more effectively transmitting force and reducing relative displacement, thereby improving the stability of the entire machine tool structure.

[0027] In this example, the present invention first monitors the geometric parameters of machine tool components, analyzes the degree of influence, screens effective geometric structure parameters, and preliminarily optimizes to obtain initial results. Based on this, local stiffness and weight are obtained, and an evaluation model is established to obtain evaluation results. Through geometric structure optimization evaluation, the effective geometric parameters and connection relationships of each component of the CNC machine tool are equivalent to the overall assembly structure, and mesh division is performed according to a preset mesh size to form macro units and connection units; by processing these units, the corresponding stiffness matrix is ​​obtained, and further integrated into a combined stiffness matrix; then a parallel optimization model is established with the goal of minimizing structural flexibility and is limited by the total volume of the macro unit and the total stiffness of the connection unit. The model is solved using sensitivity analysis and selection optimization algorithms, thereby obtaining the optimization results of the macro unit and the connection unit. This not only can accurately monitor and optimize the key geometric structure parameters of the CNC machine tool, but also can ensure the maximization of the optimization effect through a scientific evaluation model, and improve the working accuracy and stability of the machine tool, realize efficient collaborative control of the CNC machine tool in a complex working environment, and improve the overall processing accuracy and production efficiency.

[0028] Reference Figure 2 A synchronous evolutionary control system for CNC machine tools that correlates dynamic and static errors, including: a geometric structure monitoring and optimization module, an optimization result evaluation module, an assembly structure meshing module, a stiffness matrix calculation module, and a parallel model solving module; The geometry monitoring and optimization module is used to monitor and count the geometry parameters of each component during the operation of the machine tool, obtain the change value of the geometry parameters and their corresponding deformation value, and obtain the degree of influence through comparison. The degree of influence is compared and analyzed, and a set of effective geometry parameters is screened based on the comparison results. The geometry of the component is preliminarily optimized to obtain the initial geometry optimization result. The optimization result evaluation module is used to obtain the local stiffness and weight of each component according to the initial geometric structure optimization results, establish a geometric structure optimization result evaluation model, and obtain the geometric structure optimization evaluation results; The assembly structure meshing module is used to equate the effective geometric structure parameters corresponding to each component and the connection relationship between each component to the overall assembly structure based on the geometric structure optimization evaluation results. The overall assembly structure is meshed according to the preset grid size to obtain macro units and connection units. The stiffness matrix calculation module is used to obtain the unit stiffness matrix and the connection stiffness matrix by processing the macro unit and the connection unit, and then obtain the combined stiffness matrix according to the unit stiffness matrix and the connection stiffness matrix; The parallel model solving module is used to establish a parallel optimization model based on the combined stiffness matrix, with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and selection optimization algorithms to obtain the optimization results of the macro unit and the connection unit.

[0029] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A synchronous evolution control method for CNC machine tools with correlated dynamic and static errors, characterized in that: include: The structural parameters corresponding to each component and the connection relationship between the components are equivalent to the overall assembly structure. The overall assembly structure is meshed according to the preset grid size to obtain macro units and connection units; The unit stiffness matrix and the connection stiffness matrix are obtained by processing the macro unit and the connection unit respectively, and then the combined stiffness matrix is ​​obtained according to the unit stiffness matrix and the connection stiffness matrix; Based on the combined stiffness matrix, a parallel optimization model is established with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and selection optimization algorithm to obtain the optimization results of the macro unit and the connection unit.

2. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 1 is characterized in that: The grid division method is to divide the overall assembly structure of the machine tool into grids according to the grid size preset by the system and the type of each component of the machine tool and the connection method of each component, so as to obtain multiple discrete grid units, forming macro units representing each component and connection units representing the actual connection status of the components.

3. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 1 is characterized in that: The expressions of element stiffness matrix and connection stiffness matrix are: Each macro unit The element stiffness matrix expression of The calculation process is: ； Where, represents the density design variable of each macro unit, The element stiffness matrix used to identify each macro element, is the penalty factor, represents the transpose symbol of the matrix, represents the geometric matrix, is the elastic matrix of the material, represents the volume of the integral differential element; Each connection unit The connection stiffness matrix expression is: Where, Identify the connection stiffness matrix of each connection element, , is the design variable of connection stiffness, and Represents the stiffness matrix in different directions and They represent the number of nodes of the corresponding stiffness matrix.

4. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 5 is characterized in that: The combined stiffness matrix is: Based on the stiffness matrix of the macro unit and the connection unit, the contribution of each unit is accumulated to the corresponding position of the global matrix through the finite element assembly method to obtain the combined stiffness matrix ; Based on the structural mechanics behavior, the stiffness matrix of the macro unit and the connection unit is processed to obtain ; Where Defined as the initial stiffness matrix of the macro unit; Defined as the initial stiffness matrix of the connection element; Combined with the stiffness matrix .

5. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 1 is characterized in that: The parallel optimization model is established with the goal of minimizing structural flexibility and the total volume of macro units and the total stiffness of connected units as constraints: ; ； ； ； ； in, represents the objective function, represents the structural flexibility, is the transposition symbol, represents the force balance equation, is the volume constraint, represents the maximum value of the total volume of the macro unit, is the connection stiffness constraint, represents the maximum value of the total stiffness of the connection element, represents the density design variable of each macro unit, Indicates that the stiffness of the connection element is non-negative, is the displacement vector, and by solving the equilibrium equation get.

6. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 1, characterized in that: The sensitivity analysis is specifically as follows: Calculate the sensitivity corresponding to the macro unit density and the connection unit stiffness respectively; The sensitivity of the macro-cell density is: ; In the formula, a represents the penalty factor, represents the transpose of the corresponding displacement component of the macro unit, represents the corresponding displacement component of the macro unit; The sensitivity of the link element stiffness is: Where, represents the transpose of the displacement component corresponding to the connection unit, is the displacement component corresponding to the connection element.

7. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 1, characterized in that: Before the structural parameters corresponding to each component and the connection relationship between each component are equated to the overall assembly structure, the overall assembly structure is meshed according to a preset mesh size to obtain macro units and connection units, the following steps are also included, where the structural parameters corresponding to each component are geometric structure parameters; a. Monitor and compile statistics on the geometric parameters of each component during machine tool operation, obtain the change in the geometric parameters and their corresponding deformation values, and determine the degree of influence through comparison. Compare and analyze the degree of influence, and screen a valid set of geometric parameters based on the comparison results. Preliminary optimization of the component geometry is then performed to obtain the initial geometric optimization results. b. Based on the initial geometry optimization results, obtain the local stiffness and weight of each component, establish a geometry optimization result evaluation model, and obtain the geometry optimization evaluation results.

8. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 7 is characterized in that: Measure multiple geometric parameters corresponding to each component of the machine tool during the operation cycle to form a set of geometric parameters corresponding to each component ;in, Representative components, x represents the number of geometric parameter sets, is the set of geometric parameters of the component, , m represents the number of geometric structure parameters of the component, i is the index variable, and the displacement of each component of the machine tool during operation is measured using strain gauges and displacement sensors. The relationship between the geometric structure parameters and the deformation is represented by mapping ; Where B is the quantity between the geometric structure parameter and the deformation, Representation components No. geometric parameters, Representation components The geometric parameter values ​​in And its corresponding deformation value ;j is the index variable; The geometric structure parameter values ​​are obtained through experimental measurement The change in value , measure again to obtain the new deformation of the component after the geometric structure parameters are changed , the new deformation With the original deformation Calculate the difference ; Change the geometric parameters Deformation difference Calculate the ratio to get the degree of influence ; The degree of impact With preset threshold Make comparisons; The degree of impact Greater than the preset threshold The geometric parameters of the components are screened as the geometric parameters that affect the stiffness change of the corresponding components; traverse each component All geometric parameter values Collect and organize the geometric structure parameters that meet the condition of being greater than the threshold value to form a valid geometric structure parameter set; The effective geometric structure parameters corresponding to each component are selected as design variables, and a mathematical model for component geometric structure optimization is established. The geometric structure parameters of each component of the machine tool are optimized to obtain the initial geometric structure optimization results.

9. The synchronous evolution control method for CNC machine tools with correlated dynamic and static errors according to claim 8, characterized in that: A geometric structure optimization result evaluation model is established, and the geometric structure optimization evaluation results are obtained as follows: calculate represents the optimization result evaluation index and Where, Respectively represent The local stiffness and weight of each component, Respectively represent target stiffness and target weight of each component, is the weight coefficient of stiffness deviation, is the weight coefficient of weight deviation; Based on the local stiffness and weight of each component, a geometric structure optimization result evaluation model is established. ; The corresponding mathematical expression is ;in, is the indicator threshold; When the comprehensive index When it is less than or equal to the index threshold, it means that the initial geometric structure optimization meets the optimization requirements; When the comprehensive index When it is greater than the indicator threshold, the requirement is not met.

10. A synchronous evolution control system for CNC machine tools with associated dynamic and static errors, used to implement the synchronous evolution control method for CNC machine tools with associated dynamic and static errors as claimed in any one of claims 1 to 9, characterized in that: include: The assembly structure meshing module, stiffness matrix calculation module, parallel model solving module also include geometric structure monitoring optimization module, optimization result evaluation module, etc. The assembly structure meshing module is used to equate the structural parameters corresponding to each component and the connection relationship between each component to the overall assembly structure. The overall assembly structure is meshed according to the preset grid size to obtain macro units and connection units. The stiffness matrix calculation module is used to obtain the unit stiffness matrix and the connection stiffness matrix by processing the macro unit and the connection unit respectively, and then obtain the combined stiffness matrix according to the unit stiffness matrix and the connection stiffness matrix; The parallel model solving module is used to establish a parallel optimization model based on the combined stiffness matrix, with the goal of minimizing structural flexibility and the total volume of the macro unit and the total stiffness of the connection unit as constraints. The model is solved using sensitivity analysis and selection optimization algorithms to obtain the optimization results of the macro unit and the connection unit. A geometric structure monitoring and optimization module is also included before the assembly structure mesh division module, which is used to monitor and count the geometric structure parameters of each component during the operation of the machine tool, obtain the change value of the geometric structure parameter and its corresponding deformation value, and obtain the influence degree by comparing the value, compare and analyze the influence degree, screen and obtain an effective geometric structure parameter set based on the comparison result, and preliminarily optimize the component geometric structure to obtain an initial geometric structure optimization result; The optimization result evaluation module is used to obtain the local stiffness and weight of each component according to the initial geometric structure optimization results, establish a geometric structure optimization result evaluation model, and obtain the geometric structure optimization evaluation results.

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