CN117669326A

CN117669326A - Machine tool structure optimization method and device based on system low-frequency vibration mode

Info

Publication number: CN117669326A
Application number: CN202311699151.6A
Authority: CN
Inventors: 郑新胜; 甘建峰; 施东; 陈祥保; 陈柯牟
Original assignee: Shenzhen Tuozhizhe Technology Co ltd
Current assignee: Shenzhen Tuozhizhe Technology Co ltd
Priority date: 2023-12-11
Filing date: 2023-12-11
Publication date: 2024-03-08

Abstract

The application provides a machine tool structure optimization method and device based on a system low-frequency vibration mode, wherein the method comprises the following steps: according to the method, an experimental system is designed according to a target machine tool, low-frequency spectrum excitation is conducted on the experimental system corresponding to the target machine tool so as to conduct modal analysis, modal information of a target machine tool structure is obtained, then a key structure of the target machine tool is conducted on vibration mode analysis of preset orders, through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders, a structure improvement machine tool is confirmed, a reconstructed original geometric model and a structure improvement geometric model are conducted on finite element analysis respectively, forced simulation processing is conducted according to the structure improvement geometric model and modal parameters corresponding to the structure improvement machine tool, and the effect of the structure improvement machine tool on suppression of machine tool tremors is confirmed. Compared with the traditional vibration mode data analysis only aiming at the higher natural frequency, the method for optimizing the machine tool structure of the low-frequency vibration mode is provided, and the effectiveness of the machine tool structure optimization method is higher.

Description

Machine tool structure optimization method and device based on system low-frequency vibration mode

Technical Field

The application relates to the technical field of machine tool structure optimization of low-frequency vibration modes, in particular to a machine tool structure optimization method and device based on a system low-frequency vibration mode.

Background

Chatter of a machine tool refers to an unstable vibration phenomenon generated during machining of the machine tool. Such vibrations may be caused by the structure of the machine itself, the tool, the workpiece, or the cutting forces during machining, among other factors. Chatter can affect machining accuracy, surface quality, and tool life, and may even lead to damage to the machine tool. Therefore, control and reduction of machine tool chatter is important for improving machining quality and efficiency. Machining chatter of machine tools is affected by numerous factors, each of which is characteristic and has a complex relationship of interactions, which can be represented by modal parameters. The modal parameters are a group of parameters for describing the dynamic characteristics of the structure or the system, the measurement method of the modal parameters is very mature, and the modal parameters of the system can be obtained through experimental and simulation methods. The mode shape data is an important reference for optimizing the machine tool structure,

in the traditional vibration research of the machine tool, most vibration mode data focused at a higher natural frequency neglect the vibration state of the machine tool under the condition of a lower natural frequency. The vibration state of the machine tool under the condition of lower natural frequency is also one of non-negligible factors generated by the vibration of the machine tool, and the structure optimization scheme provided for the vibration of the machine tool is not perfect and has low effectiveness.

Disclosure of Invention

In view of the foregoing, it is necessary to provide a method and an apparatus for optimizing a machine tool structure based on a system low frequency mode, which can provide a method and an apparatus for optimizing a machine tool structure based on a system low frequency mode with high efficiency.

The first aspect of the application provides a machine tool structure optimization method based on a system low-frequency vibration mode, which comprises the following steps: according to the design experimental system of the target machine tool, performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool to perform modal analysis, and acquiring modal information of the structure of the target machine tool; performing vibration mode analysis of a preset order on a key structure of a target machine tool, and confirming a structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders; based on a target machine tool and a structure improvement machine tool, the constructed original geometric model and the structure improvement geometric model are respectively subjected to finite element analysis to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool; and carrying out forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble.

In one embodiment, the designing an experimental system according to the target machine tool, performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool to perform modal analysis, and obtaining modal information of the structure of the target machine tool specifically includes: setting a preset number of measuring nodes at a main structural part of a target machine tool, wherein the main structural part comprises a weak rigid structural part; confirming an experimental low-frequency spectrum based on the processing rotating speed of the daily work of the target machine tool, so as to excite the target machine tool through the experimental low-frequency spectrum; and receiving a response signal fed back by the target machine tool excited by the low-frequency spectrum, and carrying out modal analysis to obtain modal information of the structure of the target machine tool.

In one embodiment, a preset number of measurement nodes are set at a main structural part of the target machine tool, wherein after the main structural part comprises the weak structural part, and before the experimental low-frequency spectrum is confirmed based on the machining rotation speed of the daily work of the target machine tool to excite the target machine tool through the experimental low-frequency spectrum, the method further comprises: setting an excitation hammer to beat the target machine tool at the frequency of a low-frequency spectrum, and generating an excitation signal to excite the target machine tool; and acquiring vibration amplitude values generated by exciting the target machine tool by the excitation signals through a preset accelerometer, and confirming corresponding signals.

In one embodiment, the key structure includes a base, a machine body and a spindle bracket, the expression forms include swing, torsion and bending, corresponding to the key structure of the target machine tool, the vibration mode analysis of the preset order is performed, and the structure improvement machine tool is confirmed by the corresponding expression form of the key structure of the target machine tool in the vibration mode analysis of different orders, which specifically includes: selecting a vibration mode with modal effective mass larger than a preset threshold in modal information of a target machine tool structure, so as to perform preset-order vibration mode analysis on the base station, the machine body and the main shaft frame; and determining a structure improvement mode according to the representation forms of swing, torsion and bending of the base station, the machine body and the main shaft in the vibration mode analysis of the preset order so as to confirm the structure improvement machine tool.

In one embodiment, the structural modifications include adding ribs, increasing the thickness of the structure, or increasing the width of the structure in the base, fuselage, and main shaft.

In one embodiment, the method for determining the validity of the structure improvement machine tool based on the target machine tool and the structure improvement machine tool includes the steps of constructing an original geometric model and a structure improvement geometric model, and performing finite element analysis to obtain corresponding modal parameters respectively, wherein the method specifically includes: according to the real geometric structure and material information of the target machine tool, constructing an original geometric model and a structure improvement geometric model in a preset simulation algorithm; applying external force to the original geometric model and the structure improvement geometric model in a three-dimensional space for finite element analysis to obtain a first modal parameter and a second modal parameter which are respectively corresponding to the target machine tool and the structure improvement machine tool; and comparing the first modal parameter and the second modal parameter which correspond to the target machine tool and the structure improvement machine tool respectively, and judging the effectiveness of the structure improvement machine tool.

In one embodiment, the comparing the first modal parameter and the second modal parameter corresponding to the target machine tool and the structure improvement machine tool respectively, to determine the validity of the structure improvement machine tool specifically includes: when the second modal parameter corresponding to the structure improvement machine tool is better than the first modal parameter corresponding to the target machine tool, judging that the effectiveness of the structure improvement machine tool is higher; when the second modal parameter corresponding to the structure improvement machine tool is worse than the first modal parameter corresponding to the target machine tool, the effectiveness of the structure improvement machine tool is lower.

In one embodiment, the forced simulation processing is performed according to the structural improvement geometric model and the modal parameter corresponding to the structural improvement machine tool, and the method for confirming the effect of the structural improvement machine tool on inhibiting the machine tool tremble specifically includes: measuring the actual milling force of the target machine tool in the milling process; applying actual milling force conversion of a target machine tool in a milling process to an original geometric model and a structural improvement geometric model to obtain a first milling force waveform and a second milling force waveform; and comparing the first milling force waveform with the second milling force waveform, and confirming the inhibition effect of the structure improvement machine tool on the machine tool tremble.

In one embodiment, comparing the first milling force waveform with the second milling force waveform, and confirming the effect of the structure improvement machine tool on suppressing the machine tool tremble specifically includes: when the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is larger than a preset amplitude threshold, confirming that the structure improvement machine tool has a good effect of inhibiting machine tool tremble; and when the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is smaller than or equal to a preset amplitude threshold value, confirming that the structure improvement machine tool has poor effect of inhibiting machine tool tremble.

According to the embodiment of the application, the experimental system corresponding to the target machine tool is designed according to the target machine tool, the low-frequency spectrum excitation is carried out on the experimental system corresponding to the target machine tool so as to carry out modal analysis, modal information of the structure of the target machine tool is obtained, then the key structure of the target machine tool is subjected to vibration pattern analysis of preset orders, the structure improvement machine tool is confirmed through corresponding expression forms of the key structure of the target machine tool in vibration pattern analysis of different orders, then the structure improvement machine tool is based on the target machine tool and the structure improvement machine tool, the original geometric model and the structure improvement geometric model are constructed, finite element analysis is carried out respectively, corresponding modal parameters are obtained, the effectiveness of the structure improvement machine tool is judged, forced simulation processing is carried out according to the structure improvement geometric model and the modal parameters corresponding to the structure improvement machine tool, and the inhibition effect of the structure improvement machine tool on machine tool tremble is confirmed. Compared with the traditional machine tool structure which only aims at the vibration mode data analysis at the higher natural frequency, the machine tool structure with the high-frequency vibration mode is obtained.

A second aspect of the present application provides a machine tool structure optimization device based on a system low frequency vibration mode, the device comprising: the modal analysis module is used for designing an experimental system according to the target machine tool, and carrying out low-frequency spectrum excitation on the experimental system corresponding to the target machine tool so as to carry out modal analysis and acquire modal information of the structure of the target machine tool; the vibration mode analysis module is used for carrying out vibration mode analysis of a preset order on a key structure of the target machine tool, and confirming the structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders; the finite element analysis module is used for respectively carrying out finite element analysis on the constructed original geometric model and the constructed structure improvement geometric model based on the target machine tool and the structure improvement machine tool to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool; and the simulation module is used for carrying out forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble.

Drawings

Fig. 1 is a flow chart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 2 is a schematic diagram of a first sub-flow of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 3 is a second sub-flowchart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 4 is a schematic diagram of a third sub-flow of the machine tool structure optimization method based on the system low frequency vibration mode according to the embodiment of the application.

Fig. 5 is a fourth sub-flowchart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 6 is a fifth sub-flowchart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 7 is a sixth sub-flowchart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 8 is a seventh sub-flowchart of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 9 is a schematic block diagram of a machine tool structure optimizing device based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 10 is a schematic diagram of a first application scenario of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 11 is a schematic diagram of a second application scenario of the machine tool structure optimization method based on the system low frequency vibration mode according to the embodiment of the application.

Fig. 12 is a schematic diagram of a third application scenario of the machine tool structure optimization method based on the system low frequency vibration mode according to the embodiment of the application.

Fig. 13 is a schematic diagram of a fourth application scenario of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Fig. 14 is a schematic diagram of a fifth application scenario of the machine tool structure optimization method based on the system low frequency vibration mode according to the embodiment of the present application.

Fig. 15 is a schematic diagram of a sixth application scenario of a machine tool structure optimization method based on a system low frequency vibration mode according to an embodiment of the present application.

Description of the main reference signs

Modal analysis Module 1

Vibration analysis module 2

Finite element analysis module 3

Simulation module 4

Detailed Description

In describing embodiments of the present application, words such as "exemplary," "or," "such as," and the like are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "or," "such as," and the like are intended to present related concepts in a concrete fashion.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. It should be understood that, "/" means or, unless otherwise indicated herein. For example, A/B may represent A or B. The term "and/or" in this application is merely an association relationship describing an association object, and means that three relationships may exist. For example, a and/or B may represent: a exists alone, A and B exist simultaneously, and B exists alone. "at least one" means one or more. "plurality" means two or more than two. For example, at least one of a, b or c may represent: seven cases of a, b, c, a and b, a and c, b and c, a, b and c.

It should be further noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings are used for the purpose of describing particular sequences or successes, respectively. The methods disclosed in the embodiments of the present application or the methods illustrated in the flowcharts include one or more steps for implementing the methods, and the execution order of the steps may be interchanged with one another, and some steps may be deleted without departing from the scope of the claims.

The embodiment of the application firstly provides a machine tool structure optimization method based on a system low-frequency vibration mode. Referring to fig. 1, the machine tool structure optimization method based on the system low frequency vibration mode includes the following steps.

S101, designing an experimental system according to a target machine tool, and performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool to perform modal analysis to obtain modal information of a structure of the target machine tool.

Wherein, firstly, the research object is determined to be a high-precision machine tool, and the high-precision machine tool is a machine tool device with high machining precision and high production efficiency. Advanced techniques and methods are employed in the design, manufacture and assembly of such machines to ensure high precision and stability during the machining process. The high-precision machine tool is widely applied to the fields of aviation, aerospace, automobiles, dies, precision part machining and the like, and has important significance for improving the quality and the production efficiency of products. After the research object is determined to be a high-precision machine tool, sampling nodes are designed on a three-dimensional model corresponding to the high-precision machine tool, and the sampling nodes are used for measuring structural vibration conditions of the high-precision machine tool in subsequent experiments. Then, according to the common processing rotating speed mode of the high-precision machine tool, the low-frequency spectrum excited by the experimental system is confirmed. The low frequency spectrum refers to frequency components of the vibration signal in a low frequency range. Vibrations are generated by periodic or random movements of the object in the vicinity of its equilibrium position, with certain frequency characteristics. In practical applications, the spectrum analysis of the vibration signal can help us to understand the frequency components and characteristics of vibration, so as to analyze the source, propagation characteristics and influence on the structure and equipment of vibration. Low frequency vibrations are generally referred to as vibration signals having a relatively low frequency, and the specific frequency range varies depending on the application. Furthermore, by configuring an experimental instrument and constructing an experimental system, the experimental system corresponding to the target machine tool is excited in a low-frequency spectrum to perform modal analysis, and modal information of the structure of the target machine tool is obtained. Modal information refers to a set of information used to describe the dynamic characteristics of a structure in various vibration modes in structural dynamics analysis. The information mainly comprises parameters such as natural frequency, vibration mode, damping and the like. The modal information reflects the vibration response characteristics of the structure when the structure is excited externally, and has important significance for optimizing structural design, evaluating dynamic performance and controlling vibration.

S102, performing vibration mode analysis of a preset order on a key structure of the target machine tool, and confirming the structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders.

The main body and the main shaft frame are also weak rigidity parts of the target machine tool. The part with weak rigidity of the machine tool is a region in the machine tool structure, which is easy to deform when the part is subjected to external force due to design, materials or manufacturing process. In other words, the mode information effective mass of the target machine tool structure reaches the mode shape of the preset order above ninety percent of the total mass, which can be the mode shape of 1-5 steps, 1-4 steps or 1-6 steps, as the analysis target.

Further, the corresponding expression form in the vibration mode analysis of the target machine tool can be the corresponding expression form in the vibration mode analysis, and different structure improvement suggestions are provided for different types of expression forms so as to confirm the final structure improvement scheme and further confirm the structure improvement machine tool corresponding to the structure improvement scheme. The vibration mode analysis is a structural dynamics analysis method and is used for researching the vibration characteristics of the structure under different vibration modes. The principle of vibration mode analysis is mainly based on the vibration equation and modal decomposition principle of the structure. The mode shape analysis steps are as follows: 1) And establishing a finite element model of the structure, wherein the finite element model comprises information such as geometric shapes, material properties, boundary conditions, loads and the like of the structure. 2) Solving the eigenvalue problem of the structure to obtain the modal parameters of the structure, including modal frequency, modal shape and modal damping. 3) The dynamic response of the structure is expressed as a superposition of the individual vibration modes according to the principle of modal decomposition. By calculating the responses of the individual modalities, the overall response of the structure can be obtained. 4) And analyzing the vibration response of the structure, wherein the vibration response comprises indexes such as vibration amplitude, spectrum analysis, modal effective mass and the like.

S103, based on the target machine tool and the structure improvement machine tool, the constructed original geometric model and the structure improvement geometric model are respectively subjected to finite element analysis to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool.

According to the real geometric structure and material information of the target machine tool, a geometric model corresponding to the target machine tool, namely the original geometric model, is built in a preset three-dimensional platform, and the geometric model refers to a model for carrying out mathematical description on the shape and the size of an object or a structure. The raw geometric model is then put into commercial simulation software (preferably ANSYS) for meshing to obtain the raw geometric model after processing. The grid division is mainly used for dividing the geometric model into discrete finite elements or control volumes, so that numerical calculation of finite element analysis is facilitated. And then, carrying out finite element analysis on the original geometric model subjected to grid division to obtain modal parameters of preset orders of the original geometric model in three directions of XYZ in a space coordinate system, wherein the finite element analysis is a numerical calculation method for solving approximate solutions of various physical problems, and converting differential equations into algebraic equation sets by dividing continuous objects or structures into discrete finite elements, so that the computer can conveniently solve the problems. Furthermore, the mode parameters of the preset orders of the structure improvement geometric model corresponding to the structure improvement machine tool in the three directions of XYZ in the space coordinate system are obtained by using the same mode and logic. Finally, the modal parameters of the two in different orders are compared to judge the effectiveness of the structure improvement machine tool.

S104, performing forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble.

The method comprises the steps of firstly measuring milling force of a target machine tool in a milling process through a preset force sensor, obtaining a waveform chart of the milling force corresponding to the target machine tool, converting the milling force and applying the milling force to a structure improvement geometric model corresponding to the structure improvement machine tool so as to perform forced vibration simulation, and obtaining the waveform chart of the milling force corresponding to the structure improvement machine. Further, comparing the waveform diagram of the milling force corresponding to the structure improvement machine with the waveform diagram of the milling force corresponding to the target machine tool, and confirming the inhibition effect of the structure improvement machine tool on machine tool tremble according to the difference of the amplitudes of the waveform diagrams of the two waveform diagrams.

In one embodiment of the present application, and referring to fig. 2, in the step S101: according to the design of the experimental system of the target machine tool, the experimental system corresponding to the target machine tool is subjected to low-frequency spectrum excitation so as to perform modal analysis, and the modal information of the structure of the target machine tool is obtained, which specifically comprises the following steps:

s201, setting a preset number of measurement nodes at a main structural part of a target machine tool, wherein the main structural part comprises a weak rigid structural part;

it should be noted that, set up the sampling node of predetermineeing quantity at main structure position, the purpose is for measuring the main structure vibrations condition of high accuracy lathe in the follow-up experiment, and for the consideration of cost and experimental complexity, under the prerequisite of guaranteeing measurement accuracy, the quantity of sampling node should be as little as possible, and sampling node should envelope the object profile that awaits measuring, reflects the geometric characteristics of structure that awaits measuring. In addition, the sampling node should be disposed at a weak portion of rigidity of the high-precision machine tool, such as a structural portion where stress of system motion load is concentrated, for example, the weak portion usually occurs at a junction of the machine tool body and the upright, a transition region, and a region where the support surface is small, or usually occurs at a junction of the main bearing housing, a junction of the tool holding device, and a junction of the tool and the shank. The weak part of the rigidity can be selected as three parts of a base, a machine body and a main shaft bracket. And after the positions of the sampling nodes are determined, an acceleration sensor is installed at each sampling node position and is used for collecting response signals in the vibration process of the target machine tool.

S202, confirming an experimental low-frequency spectrum based on the machining rotating speed of the daily work of the target machine tool, so as to excite the target machine tool through the experimental low-frequency spectrum.

Wherein, confirm this experiment low frequency spectrum through the frequency that the processing rotational speed that the target lathe daily works corresponds, and then based on the experiment low frequency spectrum excites the target lathe. For example, the machining speed of the machine tool for routine work is about 3000rpm, and if a four-tooth solid end mill is used, the cutter tooth passing frequency is 200Hz. The sampling cut-off frequency is 200Hz, so that the influence of external excitation on the vibration of the machine tool structure can be eliminated. The corresponding experimental low frequency spectrum may then be 200Hz of the sampling cut-off frequency.

S203, receiving a response signal fed back by the target machine tool excited by the low-frequency spectrum, and performing modal analysis to acquire modal information of the structure of the target machine tool.

Before modal analysis is performed on the target machine tool, determining an experimental instrument and building an experimental system in advance according to a low-frequency spectrum and sampling nodes, wherein the experimental instrument can comprise an exciting hammer for exciting, an acceleration sensor for collecting response signals and the like. After the experimental system is built, carrying out modal analysis on the target machine tool, exciting the target machine tool at a frequency corresponding to a low-frequency spectrum, receiving response signals corresponding to the excitation signals, wherein the excitation signals and the response signals are in one-to-one correspondence to form a modal. And finally, carrying out modal analysis based on the modes, and analyzing and observing the relation between the excitation signals and the corresponding signals to obtain the modal information of the target machine tool structure.

In some preferred embodiments, referring to fig. 3, a preset number of measurement nodes are provided at a main structural part of the target machine tool, wherein after the main structural part comprises the weak structural part, and before the experimental low frequency spectrum is confirmed based on the machining rotation speed of the daily work of the target machine tool to excite the target machine tool through the experimental low frequency spectrum, the method further comprises:

and S301, setting an excitation hammer to beat the target machine tool at the frequency of the low-frequency spectrum, and generating an excitation signal to excite the target machine tool.

The exciting hammer is also called as impact hammer or modal hammer, and is a tool for experimental vibration test and modal analysis. The device is mainly used for applying impact force to a structure or a mechanical system, exciting natural vibration of the structure or the mechanical system, and measuring response signals through sensors (such as an accelerometer, a displacement meter and the like), so as to acquire dynamic characteristics (such as frequency, damping, modal shape and the like) of the structure.

S302, acquiring vibration amplitude generated by excitation of an excitation signal of a target machine tool through a preset accelerometer, and confirming corresponding signals.

In combination with the preferred application scenario of fig. 15, after the exciting hammer strikes the target machine tool with the frequency of the low-frequency spectrum, the target machine tool is excited by the exciting signal to generate vibration, and the preset accelerometer acquires the corresponding vibration amplitude, wherein the vibration amplitude is the corresponding signal.

In one embodiment of the present application, and referring to fig. 4, the step S102: the key structure comprises a base station, a machine body and a main shaft bracket, the expression forms comprise swinging, torsion and bending, the key structure of the target machine tool is subjected to vibration mode analysis of preset orders, and the structure improvement machine tool is confirmed by the corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders, and specifically comprises:

s401, selecting a vibration mode with modal effective mass larger than a preset threshold in modal information of a target machine tool structure, so as to perform vibration mode analysis of preset orders on a base station, a machine body and a main shaft frame;

s402, determining a structure improvement mode according to the representation forms of swing, torsion and bending of the base station, the machine body and the main shaft in vibration mode analysis of a preset order, so as to confirm the structure improvement machine tool.

Among them, modal effective mass is an important concept in structural dynamics for quantifying mass distribution characteristics of a structure in a specific vibration mode. The modal effective mass can help us to know the dynamic response characteristics of the structure under different vibration modes, so that basis is provided for structural design, vibration control and health monitoring. The physical meaning of the modal effective mass is: in a certain vibration mode, the sum of the products of the mode displacement and the mass of each mass unit in the structure is the mass distribution characteristic of the structure in the mode. The larger the modal effective mass, the larger the contribution of the mass distribution of the structure in the mode to the vibration response, and conversely, the smaller.

Further, the vibration mode analysis is a method for researching dynamic characteristics of a structure or a mechanical system, and is mainly aimed at determining parameters such as natural frequency (or natural frequency), vibration mode (or modal shape), damping ratio and the like of the system. The analysis of the vibration modes of different orders refers to researching the vibration modes of different natural frequencies of the structure in a low frequency range. The mode shape is the shape of vibration of the structure at the natural frequency, reflecting the relative displacement of the parts of the structure in the free vibration state. The mode shape is usually represented by a modal shape vector or cloud image, which can help us to understand the weaknesses and sensitive areas of the structure, thereby guiding the structural optimization and control design. The order in this embodiment is preferably 1-5, 1-4 or 1-6. And confirming the structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders. The key structure comprises a base station, a machine body and a main shaft bracket. The expression forms comprise swinging, twisting and bending, and the structural improvement modes comprise adding reinforcing ribs, increasing structural thickness or increasing structural width in the base station, the machine body and the main shaft.

Specifically, referring to fig. 14, the structure improvement scheme can be confirmed according to the expression form:

1) Swinging: when the main structure of the target machine tool is subjected to swing deformation, the swing deformation means that one end of the structure is smaller in displacement and the other end of the structure is larger in displacement. The rocking deformation generally occurs on an object in contact with a rigid structure such as the ground or a large rigid structure such as a base. For example, when the machine tool connected to the ground swings as a whole, the machine body connected to the base swings. The corresponding structural improvement scheme may be: reinforcing ribs are added on the left side and the right side of the structure, or the width of the structure in the swinging direction is increased, so that the swinging flutter can be restrained.

2) And (3) torsion: when the main structure of the target machine tool twists around a certain axis inside the main structure, the main structure can be regarded as torsional deformation. Similar to structural swing deformation, objects attached to rigid structures such as pedestals, floors, or large rigid structures such as pedestals are also prone to torsional deformation. For example, when the whole target machine tool is twisted relative to the ground, the machine tool body is twisted relative to the base. The corresponding structural improvement scheme may be: reinforcing ribs are added on the periphery of the structure, or the thickness of the base station is increased, so that torsional vibration can be restrained.

3) Bending: when the main structure of the target machine tool is subjected to alternating motion, bending deformation of the structure can be considered. Bending deformations usually occur at the machine tool body and sometimes also at the spindle carrier. For example, when the machine tool structure has a long length in a certain direction, bending deformation easily occurs. The corresponding structural improvement scheme may be: the reinforcing ribs are added in the bending direction of the structure, or the width of the structure in the bending direction is increased, so that the bending deformation can be restrained.

In one embodiment of the present application, and referring to fig. 5, the step S103: the method comprises the steps of constructing an original geometric model and a structural improvement geometric model based on a target machine tool and the structural improvement machine tool, respectively carrying out finite element analysis to obtain corresponding modal parameters so as to judge the effectiveness of the structural improvement machine tool, and specifically comprises the following steps:

s501, constructing an original geometric model and a structure improvement geometric model in a preset simulation algorithm according to the real geometric structure and material information of a target machine tool;

s502, applying external force to the original geometric model and the structure improvement geometric model in a three-dimensional space for finite element analysis to obtain a first modal parameter and a second modal parameter which are respectively corresponding to the target machine tool and the structure improvement machine tool;

s503, comparing the first modal parameter and the second modal parameter which correspond to the target machine tool and the structure improvement machine tool respectively, and judging the effectiveness of the structure improvement machine tool.

The construction of the corresponding geometric model is performed in a preset simulation algorithm, namely simulation software, through the real geometric structure and material information of the target machine tool, wherein the simulation software can be ANSYS, and the selection scheme of the specific simulation software is not further limited, so that the construction of the geometric model can be realized. And correspondingly constructing a geometric model of the target machine tool, namely an original geometric model, and constructing a geometric model of the structure improvement machine tool, namely a structure improvement geometric model.

Further, after the original geometric model and the structure improvement geometric model are constructed, respectively performing grid division processing on the two geometric models, wherein the grid division processing generally comprises the following steps:

1) Geometry model importation: importing the geometric model created in the CAI) software into simulation software or directly creating the geometric model in the simulation software. 2) Geometric model cleaning and simplification: the imported geometric model is cleaned and simplified, defects (such as overlapped surfaces, long and narrow surfaces and the like) in the model are eliminated, and the model is simplified according to simulation requirements (such as neglecting tiny features, merging similar areas and the like). 3) Grid type selection: suitable mesh types are selected based on simulation type and geometric model characteristics, such as structural analysis typically using tetrahedral or hexahedral meshes, and fluid analysis typically using structured or unstructured meshes. 4)

2) Setting grid division parameters: parameters of grid division such as grid size, grid density, grid growth rate and the like are set. These parameters need to be weighted according to the simulation requirements and the computing resources to ensure the accuracy and the computing efficiency of the result. 5) Grid generation: and meshing the geometric model by using a mesh generation algorithm in simulation software. The generation process may require multiple iterations and optimizations to obtain a grid quality that meets the requirements. 6) Grid quality inspection and optimization: and checking the quality of the generated grid, such as the shape, the size, the distortion and the like of the grid, and optimizing the grid which does not meet the requirements so as to improve the accuracy of the simulation result. 7)

3) Grid derivation: the generated grid is exported into a format supported by simulation software for subsequent simulation analysis. It should be noted that, the three-dimensional geometric model is divided into discrete finite element grids, which include basic elements such as nodes, units, boundaries, and the like. The quality and density of the meshing will affect the accuracy and computational efficiency of the analysis results, and therefore, optimization is required according to the structural features and objectives.

And then, respectively carrying out finite element analysis on the original geometric model and the structure improvement geometric model which are subjected to grid division processing to obtain a first modal parameter and a second modal parameter which are respectively corresponding to the target machine tool and the structure improvement machine tool, comparing the first modal parameter and the second modal parameter which are respectively corresponding to the target machine tool and the structure improvement machine tool, and judging the effectiveness of the structure improvement machine tool.

The basic steps of the finite element analysis are as follows:

1) Geometric modeling and meshing (corresponding operations have been performed previously).

2) Material property definition: the finite element mesh is assigned material properties (e.g., modulus of elasticity, poisson's ratio, etc.) and physical properties (e.g., density, coefficient of thermal expansion, etc.) to describe the mechanical and thermal properties of the machine tool structure.

3) Boundary condition setting: constraints (e.g., fixed support, sliding support, etc.) and external loads (e.g., cutting forces, gravity, heat sources, etc.), which are imposed by the machine tool structure during analysis, are defined. The boundary conditions are set by considering the working state and the environmental conditions of the machine tool so as to ensure the practicability and the reliability of analysis results.

4) Analysis type selection: according to the performance requirements of the machine tool structure, a proper finite element analysis type is selected, such as static analysis, dynamic analysis, fatigue analysis, thermal analysis and the like. Different types of analysis may provide different information and indicators such as stress, deformation, vibration, temperature, etc. (vibration in this case).

5) Problem solving: and (3) operating a finite element solver, converting information such as discrete grids, material properties, boundary conditions and the like into an algebraic equation set, and solving unknown quantities (such as displacement, stress, temperature and the like) through an iterative or direct method.

6) Post-processing results: and visually displaying the solving result (such as cloud pictures, vector pictures and the like), and extracting, analyzing and verifying data to evaluate the performance and the safety of the machine tool structure. The post-processing process may need to be compared with experimental data or experience rules to improve the reliability of the analysis results.

Specifically, referring to fig. 6, the comparing the first modal parameter and the second modal parameter corresponding to the target machine tool and the structure improvement machine tool respectively, to determine the effectiveness of the structure improvement machine tool specifically includes:

s601, judging that the effectiveness of the structure improvement machine tool is higher when the second modal parameter corresponding to the structure improvement machine tool is better than the first modal parameter corresponding to the target machine tool;

s602, when the second modal parameter corresponding to the structure improvement machine tool is worse than the first modal parameter corresponding to the target machine tool, judging that the effectiveness of the structure improvement machine tool is lower.

In some preferred embodiments, two finite element analysis results are compared, that is, for comparison of a first mode parameter and a second mode parameter corresponding to a target machine tool and a structure improvement machine tool respectively, the specific results can refer to fig. 12 (first mode parameter) and fig. 13 (second mode parameter), and the results show that the first five-order natural frequency of the structure improvement machine tool is improved compared with that of the original target machine tool, and the resonance risk is further reduced. The above results indicate the effectiveness of machine tool structure improvement.

In one embodiment of the present application, and referring to fig. 7, the step S104: the forced simulation treatment is carried out according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and the inhibition effect of the structural improvement machine tool on the machine tool tremble is confirmed, and the method specifically comprises the following steps:

S701: measuring the actual milling force of the target machine tool in the milling process;

in order to further verify the improvement effect of the machine tool based on the low-frequency vibration mode analysis, forced vibration simulation is also required for the machine tool before and after the improvement. The actual milling force of the target machine tool during the milling process is measured first by a preset sensor, which may be a Kistler 9272 force sensor.

S702: and applying actual milling force conversion of the target machine tool in the milling process to the original geometric model and the structure improvement geometric model, and obtaining a first milling force waveform and a second milling force waveform.

The method comprises the steps of obtaining actual milling force of the target machine tool in a milling process, applying the actual milling force conversion to an original geometric model and a structural improvement geometric model, and performing forced vibration simulation to obtain a first milling force waveform corresponding to the original geometric model and a second milling force waveform corresponding to the structural improvement geometric model;

s703: and comparing the first milling force waveform with the second milling force waveform, and confirming the inhibition effect of the structure improvement machine tool on the machine tool tremble.

After a first milling force waveform corresponding to the original geometric model and a second milling force waveform corresponding to the structural improvement geometric model are obtained, the waveforms are compared to confirm the inhibition effect of the structural improvement machine tool on machine tool tremble.

Specifically, referring to fig. 8, comparing the first milling force waveform with the second milling force waveform, and confirming the effect of the structure improvement machine tool in suppressing the tremble of the machine tool specifically includes:

s801: when the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is larger than a preset amplitude threshold, confirming that the structure improvement machine tool has a good effect of inhibiting machine tool tremble;

s802: and when the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is smaller than or equal to a preset amplitude threshold value, confirming that the structure improvement machine tool has poor effect of inhibiting machine tool tremble.

Referring to fig. 10 and 11, a first milling force waveform corresponding to the original geometric model and a second milling force waveform corresponding to the structurally improved geometric model according to a preferred embodiment are shown, and it is obvious that an average amplitude of the first milling force waveform corresponding to the original geometric model is significantly larger than an average amplitude of the second milling force waveform corresponding to the structurally improved geometric model. Therefore, the structure improved machine tool has better effect of inhibiting machine tool tremble.

Referring to fig. 9, the embodiment of the present application further provides a machine tool structure optimization device based on a system low frequency vibration mode, where the device may include a plurality of functional sub-modules composed of program code segments, the machine tool structure optimization device based on the system low frequency vibration mode may be divided into a plurality of functional sub-modules according to the functions executed by the machine tool structure optimization device, and the functional sub-modules at least include a modal analysis module 1, a vibration mode analysis module 2, a finite element analysis module 3 and a simulation module, where the functions of each functional sub-module are as follows:

the modal analysis module 1 is used for designing an experimental system according to a target machine tool, performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool so as to perform modal analysis, and acquiring modal information of a structure of the target machine tool;

the vibration mode analysis module 2 is used for carrying out vibration mode analysis of a preset order on a key structure of the target machine tool, and confirming the structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders;

the finite element analysis module 3 is used for respectively carrying out finite element analysis on the constructed original geometric model and the constructed structure improvement geometric model based on the target machine tool and the structure improvement machine tool to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool;

The simulation module 4 is used for performing forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble

The embodiment of the application also provides a computer storage medium. The computer storage medium stores program instructions that, when executed on the electronic device, cause the electronic device to perform the system low frequency mode-of-vibration based machine tool structure optimization method described above.

Embodiments of the present disclosure provide a computer-readable storage medium storing computer-executable instructions configured to perform the above-described machine tool structure optimization method based on a system low frequency mode of vibration.

The disclosed embodiments provide a computer program product comprising a computer program stored on a computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, cause the computer to perform the above-described machine tool structure optimization method for a system-based low frequency mode of vibration.

The computer readable storage medium may be a transitory computer readable storage medium or a non-transitory computer readable storage medium.

Embodiments of the present disclosure may be embodied in a software product stored on a storage medium, including one or more instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of a method according to embodiments of the present disclosure. And the aforementioned storage medium may be a non-transitory storage medium including: a plurality of media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or a transitory storage medium.

The above description and the drawings illustrate embodiments of the disclosure sufficiently to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. Moreover, the terminology used in the present application is for the purpose of describing embodiments only and is not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a," "an," and "the" (the) are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed. Furthermore, when used in this application, the terms "comprises," "comprising," and/or "includes," and variations thereof, mean that the stated features, integers, steps, operations, elements, and/or components are present, but that the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof is not precluded. Without further limitation, an element defined by the phrase "comprising one …" does not exclude the presence of other like elements in a process, method or apparatus comprising such elements. In this context, each embodiment may be described with emphasis on the differences from the other embodiments, and the same similar parts between the various embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method sections disclosed in the embodiments, the description of the method sections may be referred to for relevance.

Those of skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. The skilled artisan may use different methods for each particular application to achieve the described functionality, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the embodiments disclosed herein, the disclosed methods, articles of manufacture (including but not limited to devices, apparatuses, etc.) may be practiced in other ways. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the units may be merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form. The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to implement the present embodiment. In addition, each functional unit in the embodiments of the present disclosure may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than that disclosed in the description, and sometimes no specific order exists between different operations or steps. For example, two consecutive operations or steps may actually be performed substantially in parallel, they may sometimes be performed in reverse order, which may be dependent on the functions involved. Each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

It will be evident to those skilled in the art that the present application is not limited to the details of the foregoing illustrative embodiments, and that the present application may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The above-described embodiments of the application are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

1. The machine tool structure optimization method based on the system low-frequency vibration mode is characterized by comprising the following steps of:

according to the design experimental system of the target machine tool, performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool to perform modal analysis, and acquiring modal information of the structure of the target machine tool;

performing vibration mode analysis of a preset order on a key structure of a target machine tool, and confirming a structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders;

based on a target machine tool and a structure improvement machine tool, the constructed original geometric model and the structure improvement geometric model are respectively subjected to finite element analysis to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool;

And carrying out forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble.

2. The machine tool structure optimization method based on the system low-frequency vibration mode according to claim 1, wherein the designing the experimental system according to the target machine tool, performing low-frequency spectrum excitation on the experimental system corresponding to the target machine tool to perform modal analysis, and obtaining modal information of the structure of the target machine tool, specifically includes:

setting a preset number of measuring nodes at a main structural part of a target machine tool, wherein the main structural part comprises a weak rigid structural part;

confirming an experimental low-frequency spectrum based on the processing rotating speed of the daily work of the target machine tool, so as to excite the target machine tool through the experimental low-frequency spectrum;

and receiving a response signal fed back by the target machine tool excited by the low-frequency spectrum, and carrying out modal analysis to obtain modal information of the structure of the target machine tool.

3. The system low frequency vibration mode based machine tool structure optimizing method according to claim 2, wherein a preset number of measurement nodes are provided at a main structural part of the target machine tool, wherein after the main structural part includes a weak structural part, and before the target machine tool is excited by the experimental low frequency spectrum, the method further comprises:

Setting an excitation hammer to beat the target machine tool at the frequency of a low-frequency spectrum, and generating an excitation signal to excite the target machine tool;

and acquiring vibration amplitude values generated by exciting the target machine tool by the excitation signals through a preset accelerometer, and confirming corresponding signals.

4. The method for optimizing a machine tool structure based on a system low-frequency vibration mode according to claim 1, wherein the key structure comprises a base, a machine body and a main shaft frame, the expression forms comprise swing, torsion and bending, the key structure of the target machine tool is subjected to vibration mode analysis of a preset order correspondingly, and the structure improvement machine tool is confirmed through the corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders, and the method specifically comprises the following steps:

selecting a vibration mode with modal effective mass larger than a preset threshold in modal information of a target machine tool structure, so as to perform preset-order vibration mode analysis on the base station, the machine body and the main shaft frame;

and determining a structure improvement mode according to the representation forms of swing, torsion and bending of the base station, the machine body and the main shaft in the vibration mode analysis of the preset order so as to confirm the structure improvement machine tool.

5. The method of optimizing a machine tool structure based on a low frequency vibration mode of a system according to claim 4, wherein the structural improvement comprises adding reinforcing ribs, increasing a structural thickness or increasing a structural width in a base, a machine body and a main shaft.

6. The method for optimizing a machine tool structure based on a system low frequency vibration mode according to claim 1, wherein the method for optimizing a machine tool structure based on a target machine tool and a structure improvement machine tool is characterized in that the method comprises the steps of constructing an original geometric model and a structure improvement geometric model, and respectively performing finite element analysis to obtain corresponding modal parameters to judge the effectiveness of the structure improvement machine tool, and specifically comprises the following steps:

according to the real geometric structure and material information of the target machine tool, constructing an original geometric model and a structure improvement geometric model in a preset simulation algorithm;

applying external force to the original geometric model and the structure improvement geometric model in a three-dimensional space for finite element analysis to obtain a first modal parameter and a second modal parameter which are respectively corresponding to the target machine tool and the structure improvement machine tool;

and comparing the first modal parameter and the second modal parameter which correspond to the target machine tool and the structure improvement machine tool respectively, and judging the effectiveness of the structure improvement machine tool.

7. The method for optimizing a machine tool structure based on a system low frequency vibration mode according to claim 6, wherein the comparing the first modal parameter and the second modal parameter corresponding to the target machine tool and the structure improvement machine tool respectively, and determining the effectiveness of the structure improvement machine tool specifically comprises:

When the second modal parameter corresponding to the structure improvement machine tool is better than the first modal parameter corresponding to the target machine tool, judging that the effectiveness of the structure improvement machine tool is higher;

when the second modal parameter corresponding to the structure improvement machine tool is worse than the first modal parameter corresponding to the target machine tool, the effectiveness of the structure improvement machine tool is lower.

8. The system low-frequency vibration mode-based machine tool structure optimization method according to claim 1, wherein the forced simulation processing is performed according to a structure improvement geometric model and modal parameters corresponding to the structure improvement machine tool, and the inhibition effect of the structure improvement machine tool on machine tool tremble is confirmed, specifically comprising:

measuring the actual milling force of the target machine tool in the milling process;

applying actual milling force conversion of a target machine tool in a milling process to an original geometric model and a structural improvement geometric model to obtain a first milling force waveform and a second milling force waveform;

and comparing the first milling force waveform with the second milling force waveform, and confirming the inhibition effect of the structure improvement machine tool on the machine tool tremble.

9. The system low frequency vibration mode based machine tool structure optimization method according to claim 8, wherein comparing the first milling force waveform with the second milling force waveform, and confirming the suppression effect of the structure improvement machine tool on the machine tool vibration specifically comprises:

When the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is larger than a preset amplitude threshold, confirming that the structure improvement machine tool has a good effect of inhibiting machine tool tremble;

and when the difference between the average amplitude of the first milling force waveform and the average amplitude of the second milling force waveform is smaller than or equal to a preset amplitude threshold value, confirming that the structure improvement machine tool has poor effect of inhibiting machine tool tremble.

10. A machine tool structure optimizing device based on a system low frequency vibration mode, characterized in that the device comprises:

the modal analysis module is used for designing an experimental system according to the target machine tool, and carrying out low-frequency spectrum excitation on the experimental system corresponding to the target machine tool so as to carry out modal analysis and acquire modal information of the structure of the target machine tool;

the vibration mode analysis module is used for carrying out vibration mode analysis of a preset order on a key structure of the target machine tool, and confirming the structure improvement machine tool through corresponding expression forms of the key structure of the target machine tool in vibration mode analysis of different orders;

the finite element analysis module is used for respectively carrying out finite element analysis on the constructed original geometric model and the constructed structure improvement geometric model based on the target machine tool and the structure improvement machine tool to obtain corresponding modal parameters so as to judge the effectiveness of the structure improvement machine tool;

And the simulation module is used for carrying out forced simulation treatment according to the structural improvement geometric model and the modal parameters corresponding to the structural improvement machine tool, and confirming the inhibition effect of the structural improvement machine tool on the machine tool tremble.