Air floating foot stiffness acquisition method, device and computer equipment

Abstract

Embodiments of the present application provide a kind of air float foot rigidity acquisition method, device and computer equipment.Air float foot rigidity is simulated by the test component arranged on machine tool, and the acquisition method includes: the free modal test is carried out to working component, generates the material attribute of working component;Multiple air inlet data are obtained by adjusting test component;Working component, air float foot and working platform support are carried out to constraint modal test, and the modal data corresponding to each air inlet data is generated, wherein, air inlet data includes air inlet pressure and air film thickness;Based on material attribute and multiple modal data, constraint modal simulation analysis is carried out to working component, air float foot and working platform support, and the air float foot rigidity corresponding to each air inlet data is generated;According to multiple air inlet data and the air float foot rigidity corresponding to multiple air inlet data, determine fitting surface;According to fitting surface, the air float foot rigidity corresponding to target air inlet data is obtained, improve the accuracy of fitting surface prediction rigidity data.

Description

Technical Field

[0001] This invention relates to the field of simulation analysis technology, and in particular to a method, apparatus, and computer device for obtaining the stiffness of an air-bearing foot. Background Technology

[0002] Air-bearing feet have low frictional resistance, near-zero wear rate, low noise, low vibration, smooth movement, and high precision, making them a motion guide and load-bearing component.

[0003] To achieve the support and constraint effects of the air-supported foot in simulation analysis, a spring element was created between the air-supported foot and the mounting plate by constraining the six degrees of freedom of the air-supported foot's bottom surface and assigning it vertical stiffness data, thus achieving an equivalent treatment of the air-supported foot. However, the air film thickness of the air-supported foot is very small, and the spring element has low precision, making it impossible to simulate the actual air film thickness. This results in a large error in the stiffness data of the equivalent spring, leading to low accuracy in obtaining the air-supported foot stiffness. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a method, apparatus, and computer device for obtaining the stiffness of an air buoyancy foot, so as to improve the accuracy of obtaining the stiffness of the air buoyancy foot.

[0005] On one hand, embodiments of the present invention provide a method for obtaining the stiffness of an air-bearing foot. The stiffness of the air-bearing foot is simulated using a test assembly mounted on a machine tool. The test assembly includes an assembly component, an adjustment component, an air-bearing foot, and a work platform support. The assembly component includes a working component. The method for obtaining the stiffness includes:

[0006] Free modal testing is performed on the working component to generate the material properties of the working component;

[0007] Multiple intake data points are obtained by adjusting the aforementioned tuning components;

[0008] Constrained modal tests are performed on the working components, the air-bearing feet, and the working platform support to generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness;

[0009] Based on the material properties and multiple modal data, constrained modal simulation analysis is performed on the working component, the air-bearing foot and the working platform support to generate the air-bearing foot stiffness corresponding to each air intake data.

[0010] The fitted surface is determined based on multiple intake data and the corresponding air bearing stiffness of the multiple intake data.

[0011] Based on the fitted surface, the stiffness of the air bearing foot corresponding to the target air intake data is obtained.

[0012] Optionally, the assembly assembly further includes a force hammer and an acceleration sensor. The acceleration sensor is disposed on the working assembly and is used to collect a first acceleration signal generated when the working assembly is excited by the force hammer. The step of performing free modal testing on the working assembly to generate the material properties of the working assembly includes:

[0013] The data acquisition system receives the first acceleration signal sent by the acceleration sensor.

[0014] First test data is generated based on the first acceleration signal;

[0015] Finite element analysis is performed on the working component to simulate its properties and obtain the first simulation data of the working component.

[0016] The simulation properties are adjusted based on the first test data and the first simulation data to generate the material properties of the working component.

[0017] Optionally, the modal data includes mode shapes and natural frequencies, and the tuning component includes a pressure regulating device and a length measuring device; the constrained modal testing of the working component, the air bearing foot, and the working platform support to generate modal data corresponding to each air intake data includes:

[0018] Adjust the pressure regulating device to obtain multiple intake air pressures;

[0019] Multiple air film thicknesses were measured using the length measuring device.

[0020] At each intake air pressure and air film thickness, the acceleration sensor collects the second acceleration signal generated when the working component is excited by the force hammer.

[0021] The data acquisition system receives the second acceleration signal sent by the acceleration sensor.

[0022] Second test data is generated based on the second acceleration signal, wherein the second test data is the mode shape and natural frequency corresponding to each intake data.

[0023] Optionally, the step of performing constrained modal simulation analysis on the working component, the air-bearing foot, and the working platform support based on the material properties and multiple modal data, and generating the air-bearing foot stiffness corresponding to each air intake data, includes:

[0024] Assign the material properties to the working component, preset the air-floating foot stiffness to the air-floating foot, and perform finite element analysis on the working component, the air-floating foot, and the working platform support to generate second simulation data;

[0025] Based on the second test data and the second simulation data, the air bearing stiffness corresponding to each air intake data is generated.

[0026] Optionally, determining the fitted surface based on multiple intake data and the corresponding air bearing stiffness includes:

[0027] From the multiple intake data, the first intake data is selected to perform constraint modal testing on the working component, the air float, and the working platform support, thereby generating the first modal data corresponding to the first intake data;

[0028] Obtain the equivalent spring stiffness data corresponding to the first intake data from the fitted surface;

[0029] Simulation analysis is performed on the working component, the air-bearing foot, and the working platform support, which are given the equivalent spring stiffness data, to generate second modal data;

[0030] The fitted surface is determined based on the first modal data and the second modal data.

[0031] Optionally, the first modal data includes a first mode shape and a first natural frequency, and the second modal data includes a second mode shape and a second natural frequency. Determining the fitted surface based on the first modal data and the second modal data includes:

[0032] Determine whether the first mode shape and the second mode shape are consistent, and whether the difference between the first natural frequency and the second natural frequency is less than a set threshold;

[0033] If it is determined that the first mode shape and the second mode shape are the same, and the difference between the first natural frequency and the second natural frequency is less than a set threshold, then the multiple air intake data of the second mode data and the air bearing stiffness corresponding to the multiple air intake data are determined as the fitted surface.

[0034] On the other hand, embodiments of the present invention provide a testing component applied to the above-mentioned method for obtaining the stiffness of an air-bearing foot, comprising:

[0035] The work platform support is mounted on the bed; the air-bearing foot is mounted on the bed; the adjustment device is mounted on the bed; the bed is used to support the work assembly; the work platform support is mounted on the bed; the force hammer is mounted on the bed; the acceleration sensor is mounted on the work assembly.

[0036] On the other hand, embodiments of the present invention provide a device for obtaining the stiffness of an air-bearing foot. The stiffness of the air-bearing foot is simulated using a test assembly mounted on a machine tool. The test assembly includes an assembly component, an adjustment component, an air-bearing foot, and a work platform support. The assembly component includes a working component. The acquisition device includes:

[0037] The first generation module is used to perform free modal testing on the working component and generate the material properties of the working component;

[0038] The first acquisition module is used to acquire multiple intake data by adjusting the adjustment component;

[0039] The second generation module is used to perform constraint modal testing on the working component, the air-bearing foot and the working platform support, and generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness.

[0040] The third generation module is used to perform constrained modal simulation analysis on the working component, the air-floating foot and the working platform support based on the material properties and multiple modal data, and generate the air-floating foot stiffness corresponding to each air intake data.

[0041] The determination module is used to determine the fitting surface based on multiple air intake data and the corresponding air bearing stiffness of the multiple air intake data.

[0042] The second acquisition module is used to acquire the air bearing stiffness corresponding to the target air intake data based on the fitted surface.

[0043] On the other hand, embodiments of the present invention provide a storage medium, wherein the storage medium includes a stored program, wherein when the program is executed, the device where the storage medium is located is controlled to execute the above-described method for obtaining the stiffness of the air buoyancy foot.

[0044] On one hand, embodiments of the present invention provide a computer device, including a memory and a processor. The memory is used to store information including program instructions, and the processor is used to control the execution of the program instructions. When the program instructions are loaded and executed by the processor, the steps of the above-described method for obtaining the stiffness of the air buoyancy foot are implemented.

[0045] In the technical solution of the method for obtaining the stiffness of the air-bearing foot provided in this invention embodiment, the stiffness of the air-bearing foot is simulated by a test component set on a machine tool. The test component includes an assembly component, an adjustment component, the air-bearing foot, and a work platform support. The assembly component includes a working component. Free modal testing is performed on the working component to generate the material properties of the working component. Multiple air intake data are obtained by adjusting the adjustment component. Constrained modal testing is performed on the working component, the air-bearing foot, and the work platform support to generate modal data corresponding to each air intake data. The air intake data includes the air intake pressure. The simulation process involves considering the air film thickness, material properties, and multiple modal data. Constrained modal simulation analysis is performed on the working components, air-supported feet, and working platform support to generate the air-supported foot stiffness corresponding to each air intake data point. A fitting surface is determined based on multiple air intake data points and their corresponding air-supported foot stiffnesses. The air-supported foot stiffness corresponding to the target air intake data is obtained from the fitting surface. Predicting the air-supported foot stiffness using the fitting surface improves simulation efficiency. Furthermore, the surface is validated and its parameters adjusted using the target air intake data, enhancing the accuracy of the stiffness data predicted by the fitting surface. Attached Figure Description

[0046] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A flowchart illustrating a method for obtaining the stiffness of an air-bearing foot according to an embodiment of the invention;

[0048] Figure 2 This is a schematic diagram of a free modal test of a working component according to an embodiment of the present invention;

[0049] Figure 3 A schematic diagram illustrating the constraint modal simulation analysis of a working component, an air-bearing foot, and a working platform support according to an embodiment of the present invention;

[0050] Figure 4 This is a schematic diagram of a fitted surface provided in an embodiment of the present invention;

[0051] Figure 5 A flowchart for determining a fitted surface is provided as an embodiment of the invention;

[0052] Figure 6 This is a schematic diagram of a device for obtaining the stiffness of an air-bearing foot according to an embodiment of the present invention;

[0053] Figure 7This is a schematic diagram of the structure of a determining module provided in an embodiment of the present invention;

[0054] Figure 8 This is a schematic diagram of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0055] To better understand the technical solution of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0056] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0057] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0058] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0059] In one embodiment of the present invention, the air float can be defined as two machining surfaces separated by an air film. An air intake device can be used to thoroughly dry external compressed air, which is then introduced into the gap between the air float and the machine bed through air intake holes on the surface of the air float. This fills the space between the air float and the machine bed with compressed air, and the resulting air film supports the load and achieves smooth operation. Because the thickness of the air film in the air float is very small (micrometer level), and the simulation of the air float often involves fluid-structure interaction issues, simulating the air float presents significant challenges.

[0060] In one embodiment of the present invention, many factors affect the stiffness of the air-supported foot, including the surface roughness of the air-supported foot, the intake air pressure, the air film thickness between the air-supported foot and the work platform, the type of internal cavity structure of the air-supported foot, and the size of the external hole. If the air-supported feet used in the same machine tool are all of the same model, the surface roughness, the type of internal cavity structure, and the size of the external hole are basically the same. Only the intake air pressure and the air film thickness between the air-supported foot and the work platform will vary due to different actual working conditions. It is necessary to study the relationship between the intake air pressure, the air film thickness, and the stiffness of the air-supported foot to obtain a fitted surface of the air-supported foot stiffness with respect to the intake air pressure and the air film thickness. In subsequent simulation analysis, the corresponding equivalent spring stiffness can be directly obtained from the surface based on the intake air pressure and the air film thickness of the air-supported foot, which not only improves the accuracy of the simulation but also saves the cost of repeated testing.

[0061] One embodiment of the present invention provides a method for obtaining the stiffness of the air buoyancy foot. Figure 1 A flowchart illustrating a method for obtaining the stiffness of an air-bearing foot according to an embodiment of the invention is provided, as follows: Figure 1 As shown, the method includes:

[0062] Step 102: Perform free modal testing on the working component to generate the material properties of the working component.

[0063] In one embodiment of the present invention, the steps are performed by a computer device. For example, the computer device includes a computer or a tablet computer.

[0064] In one embodiment of the present invention, the stiffness of the air-bearing foot is simulated by a test component set on a machine tool. The test component includes an assembly component, an adjustment component, an air-bearing foot, and a work platform support. The assembly component includes a working component.

[0065] In one embodiment of the present invention, the material properties include elastic modulus, density, Poisson's ratio, etc.

[0066] Figure 2 This is a schematic diagram of a free modal test of a working component according to an embodiment of the present invention, as shown below. Figure 2 As shown, the system includes: a data acquisition system 1, a computer device 2, a bed 3, a hammer 4, a working assembly 5, an accelerometer 6, and a foam pad 7. The foam pad 7 supports the working assembly 5, reducing the constraint of the ground on it. The data acquisition system 1 is communicatively connected to the hammer 4, the accelerometer 6, and the computer device 2.

[0067] In one embodiment of the present invention, the working component 5 can be an F2MH worktable base frame.

[0068] In this invention, a hammer 4 strikes the working component 5 to generate excitation. An accelerometer 6 collects the first acceleration signal generated by the working component 5 under the excitation of the hammer 4. The accelerometer 6 transmits the first acceleration signal to a data acquisition system 1, which converts it into a first data signal. The data acquisition system 1 then transmits the first data signal to a computer device 2. The computer device 2 processes the first data signal, calculates the transfer function based on the relationship between excitation and response, and obtains the first test data of the working component 5 based on the transfer function. The first test data includes multiple natural frequencies and mode shapes. The computer device 2 performs finite element analysis on the working component 5 to simulate the properties of the assembly component and obtains the first simulation data of the working component 5, which includes multiple natural frequencies and mode shapes. The computer device 2 approximates the first simulation data with the first test data and adjusts the simulated properties so that the difference between the first test data and the first simulation data is less than a set difference threshold. In one embodiment of the invention, a set difference threshold can be set according to the actual situation.

[0069] As an alternative, when the mode shape in the first test data is the same as the mode shape in the first simulation data, and the difference between the natural frequency in the first test data and the natural frequency in the first simulation data is less than a set difference threshold, the simulated properties are the material properties of the assembly component.

[0070] In one embodiment of the present invention, as Figure 2 As shown, the assembly components include: bed 3, hammer 4, working component 5 and acceleration sensor 6. The working component 5 is mounted on the bed 3, the hammer 4 is mounted on the bed 3 and is used to strike the working component 5, and the acceleration sensor 6 is mounted on the working component 5.

[0071] Furthermore, the assembly component may also include a foam pad 7, which supports the working component 5 and reduces the constraint of the ground on the working component 5.

[0072] Step 104: Obtain multiple intake data by adjusting the testing components.

[0073] In one embodiment of the present invention, the adjustment component includes a voltage adjustment device and a length measuring device.

[0074] In one embodiment of the present invention, multiple intake data points need to be obtained by changing the intake conditions through a pressure regulating device in order to conduct multiple sets of tests and ensure the accuracy of the simulation analysis of the stiffness of the air bearing foot.

[0075] As an optional approach, the initial intake data is used as a starting reference point (relative to zero) because intake has not yet started and the system is in a closed state. Subsequent intake data are obtained by subtracting the parameters from those in the intake state and the closed state.

[0076] For example, the intake air pressure is changed by a pressure regulating device and displayed in real time. The air film thickness is changed by adjusting the air foot nut, and the height of the air float is measured using a length measuring device. The air film thickness is obtained by continuously switching between the air supply and air cut-off states. For example, if the length measuring device displays 75 μm in the air supply state and 50 μm in the air cut-off state, then the air film thickness is 25 μm. Throughout the process, the air film thickness must remain stable before and after the test. After changing the conditions, steps 104 to 108 are repeated to obtain the air float stiffness under the given intake air pressure and air film thickness conditions.

[0077] Step 106: Perform constrained modal tests on the working components, air bearing feet, and working platform support to generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness.

[0078] In one embodiment of the present invention, the modal data includes mode shapes and natural frequencies.

[0079] Specifically, based on multiple intake air pressures and air film thicknesses, the test component can be excited in multiple directions using a moving force hammer method or a moving sensor method to generate the mode shape and natural frequency corresponding to each intake air pressure and air film thickness.

[0080] As an alternative, the test component can be excited in multiple directions by using a moving force hammer method based on multiple intake air pressures and air film thicknesses, which can fully excite the test component to vibrate in various directions, making the vibration mode easier to observe.

[0081] In one embodiment of the present invention, the air-bearing foot can be equivalently represented by a Spring model and given stiffness data.

[0082] During constrained modal testing, the assembly components are mounted onto the machine bed using the work platform support and air bearing feet to obtain the test components. Figure 3 This is a schematic diagram illustrating the constraint modal simulation analysis of a working component, an air-bearing foot, and a working platform support according to an embodiment of the present invention, as shown below. Figure 3 As shown, the test assembly includes: a data acquisition system 1, a computer device 2, a bed 3, a hammer 4, a working component 5, an accelerometer 6, a work platform support 8, a pressure regulating device 9, a length measuring device 10, and an air-bearing foot 11. The pressure regulating device 9 is used to adjust multiple intake data points by changing the intake conditions and to measure the intake air pressure. The length measuring device 10 is used to measure the air film thickness. The pressure regulating device 9 may include a pressure regulating valve, and the length measuring device 10 may include a micrometer. The data acquisition system 1 is communicatively connected to the hammer 4, the accelerometer 6, and the computer device 2 is communicatively connected to the data acquisition system 1.

[0083] In this process, at each intake air pressure and film thickness, the hammer 4 strikes the test component to generate excitation. The accelerometer 6 collects the second acceleration signal generated when the test component is excited by the hammer 4. The accelerometer 6 transmits the second acceleration signal to the data acquisition system 1. The data acquisition system 1 converts the second acceleration signal into a second data signal and transmits it to the computer device 2. The computer device 2 processes the second data signal, calculates the transfer function based on the relationship between excitation and response, and obtains the second test data of the test component based on the transfer function. The second test data includes multiple natural frequencies and mode shapes corresponding to each intake data point.

[0084] Step 108: Based on material properties and multiple modal data, perform constrained modal simulation analysis on the working component, air bearing foot, and working platform support to generate the air bearing foot stiffness corresponding to each air intake data.

[0085] Specifically, constrained modal simulation analysis is performed on the working components, air-bearing feet, and working platform supports based on material properties and multiple modal data. The stiffness of the air-bearing feet corresponding to each air intake data is adjusted according to the mode shape and natural frequency to generate the adjusted stiffness of the air-bearing feet corresponding to each air intake data.

[0086] like Figure 3 As shown, computer device 2 assigns the material properties obtained in step 102 to working component 5, presets the air bearing stiffness for air bearing foot 11, and performs finite element analysis on the test component to generate second simulation data. The second simulation data includes multiple natural frequencies and mode shapes corresponding to each air intake data. Computer device 2 approximates the second simulation data with the second test data and adjusts the set air bearing stiffness corresponding to the air intake data according to the second test data and the second simulation data.

[0087] In one embodiment of the present invention, the set air-float stiffness can be set according to the actual situation.

[0088] As an optional approach, when the mode shape in the second test data is the same as the mode shape in the second simulation data, and the difference between the natural frequency in the second test data and the natural frequency in the second simulation data is less than a set difference threshold, the air bearing stiffness corresponding to the adjusted intake data is generated.

[0089] By changing the intake conditions using the pressure regulating device 9 and repeating the above steps, the air bearing stiffness corresponding to the adjusted multiple sets of intake data is obtained, that is, the air bearing stiffness corresponding to each set of intake data.

[0090] Figure 3 The number of air-bearing feet 11 is 2. However, other numbers of air-bearing feet 11 can be used for testing based on actual application conditions. This embodiment of the invention does not limit this.

[0091] In one embodiment of the present invention, as Figure 3 As shown, the test components include: bed 3, force hammer 4, working component 5, acceleration sensor 6, air bearing foot 11, working platform support 8, pressure regulating device 9, and length measuring device 10.

[0092] The work platform support 8 is mounted on the bed 3; the air float 11 is mounted on the bed 3; the pressure regulating device 9 mounted on the bed 3 is used to change the air intake conditions, adjust multiple air intake data, and measure the air intake pressure; the length measuring device 10 mounted on the bed 3 is used to measure the air film thickness; the bed 3 is used to support the working component 5; the work platform support 8 is mounted on the bed 3; the force hammer 4 mounted on the bed 3 is used to strike the working component 5; and the acceleration sensor 6 is mounted on the working component 5.

[0093] The technical solution provided in this embodiment of the invention is applicable to obtaining the stiffness of air-floating feet in any type of structure that can be fitted with air-floating feet. Therefore, the test components selected in this embodiment of the invention can be replaced by any other type of structure that can be fitted with air-floating feet.

[0094] In one embodiment of the present invention, when performing constrained modal simulation analysis, the stiffness parameters are first approximated by those modes whose vibration modes are more pronounced in a single direction. This is beneficial for adjusting the stiffness of the air-bearing foot in that direction. More appropriately, rigid body modes (whose vibration modes are entirely reflected in a single direction) can be selected for approximation, and then the parameters can be fine-tuned by combining them with complex vibration modes until the error is reduced to a certain order of magnitude. Since the air-bearing foot only has stiffness in the vertical direction, the stiffness parameters can be approximated by selecting the mode that moves in the vertical direction, in conjunction with the above method.

[0095] Step 110: Determine the fitted surface based on multiple intake data and the corresponding air bearing stiffness.

[0096] In one embodiment of the present invention, the intake air pressure and air film thickness are continuously adjusted to obtain a series of correspondences between the air float stiffness and the intake air pressure and air film thickness, and these correspondences are fitted into a surface of "air float stiffness - intake air pressure and air film thickness". As many tests as possible should be conducted under different conditions to obtain data, as this will result in a better fitting effect.

[0097] In practice, modal tests under different inlet air pressure and film thickness conditions can be performed all at once, and then a unified analysis can be conducted. The inlet air pressure and film thickness should be adjusted within the production standard range.

[0098] Figure 4 This is a schematic diagram of a fitted surface provided in an embodiment of the present invention, as shown below. Figure 4As shown, the fitted surface is a surface showing the correspondence between the stiffness of the air float foot and the intake air pressure and the air film thickness. The horizontal axis of the fitted surface is the air film thickness H, the vertical axis is the intake air pressure P, and the vertical axis is the stiffness of the air float foot K.

[0099] To verify the accuracy of the fitted surface, the intake air pressure and air film thickness corresponding to the intake data can be obtained using the test components. Based on the measured intake air pressure and air film thickness, the equivalent spring stiffness data of the air float foot is selected from the fitted surface and assigned to the spring element in the finite element model for finite element analysis. Then, the first modal data of the constraint modal test is compared with the second modal data of the simulation.

[0100] Specifically, Figure 5 A flowchart for determining a fitted surface is provided in one embodiment of the present invention, as follows: Figure 5 As shown, step 110 includes:

[0101] Step 1102: Select the first intake data from multiple intake data and perform constraint modal testing on the working component, air bearing foot and working platform support to generate the first modal data corresponding to the first intake data.

[0102] Specifically, a specific intake air pressure and air film thickness condition can be selected to re-perform the constrained modal test and obtain the natural frequency and mode shape at this time.

[0103] Step 1104: Obtain the equivalent spring stiffness data corresponding to the first intake data from the fitted surface.

[0104] Specifically, the equivalent spring stiffness corresponding to the same intake air pressure and air film thickness as in step 1102 is selected from the fitted surface.

[0105] Step 1106: Perform simulation analysis on the working components, air-bearing feet, and working platform supports with assigned equivalent spring stiffness data to generate second modal data.

[0106] Step 1108: Determine the fitted surface based on the first modal data and the second modal data.

[0107] In one embodiment of the present invention, the first modal data includes a first mode shape and a first natural frequency, and the second modal data includes a second mode shape and a second natural frequency.

[0108] As an optional approach, step 1108 includes: determining whether the first mode shape and the second mode shape are consistent, and whether the difference between the first natural frequency and the second natural frequency is less than a set threshold. If the first mode shape and the second mode shape are consistent and the difference between the first natural frequency and the second natural frequency is less than the set threshold, it indicates that the fitted surface determined based on multiple intake data of the second modal data and the corresponding air bearing stiffness is relatively reliable, and the process ends. If the first mode shape and the second mode shape are inconsistent, and / or the difference between the first natural frequency and the second natural frequency is greater than or equal to the set threshold, it indicates that the number of tested intake data is insufficient, and step 104 continues; or it indicates that the fitting surface method in step 108 is inappropriate, and a different fitting method is used to return to step 108.

[0109] In one embodiment of the present invention, a threshold value can be set according to the actual situation of the industrial application scenario. The more precise the processing equipment, the smaller the threshold value. As an optional solution, the threshold value can be calculated as follows: First, calculate the absolute value of the difference between the natural frequency of the simulated data and the natural frequency of the test data; then calculate the ratio of this absolute value to the natural frequency of the test data; finally, multiply this ratio by 100% to obtain the threshold value. For example, the threshold value may be 10%, 5%, or 2%.

[0110] Step 112: Obtain the air bearing stiffness corresponding to the target intake data based on the fitted surface.

[0111] In one embodiment of the present invention, during future simulation analysis, the stiffness of the air-bearing foot corresponding to the air pressure and air film thickness can be directly obtained from the fitted surface based on the air pressure and air film thickness of the air-bearing foot. This not only improves the accuracy of the simulation but also saves the cost of repeated testing.

[0112] In the technical solution provided by this invention, the stiffness of the air-bearing foot is simulated using a test component mounted on a machine tool. The test component includes an assembly component, an adjustment component, the air-bearing foot, and a work platform support. The assembly component includes a work component. Free modal testing is performed on the work component to generate its material properties. Multiple air intake data are obtained by adjusting the adjustment component. Constrained modal testing is performed on the work component, the air-bearing foot, and the work platform support to generate modal data corresponding to each air intake data point. The air intake data includes air intake pressure and air film thickness. Based on the material properties and multiple modal data, constrained modal simulation analysis is performed on the work component, the air-bearing foot, and the work platform support to generate the stiffness of the air-bearing foot corresponding to each air intake data point. A fitting surface is determined based on the multiple air intake data points and the corresponding air-bearing foot stiffness. The air-bearing foot stiffness corresponding to the target air intake data is obtained based on the fitting surface. Predicting the air-bearing foot stiffness using the fitting surface improves simulation efficiency. Furthermore, the surface is verified and its parameters are adjusted using the target air intake data, improving the accuracy of the stiffness data predicted by the fitting surface.

[0113] One embodiment of the present invention provides a device for obtaining the stiffness of an air-bearing foot. Figure 6 This is a schematic diagram of a device for obtaining the stiffness of an air-bearing foot according to an embodiment of the present invention, as shown below. Figure 6 As shown, the device includes: a first generation module 11, a first acquisition module 12, a second generation module 13, a third generation module 14, a determination module 15, and a second acquisition module 16.

[0114] The first generation module 11 is used to perform free modal testing on the working component and generate the material properties of the working component.

[0115] The first acquisition module 12 is used to acquire multiple intake data by adjusting the testing components.

[0116] The second generation module 13 is used to perform constrained modal tests on the working components, air bearing feet and working platform supports, and generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness.

[0117] The third generation module 14 is used to perform constrained modal simulation analysis on the working components, air bearing feet and working platform supports based on material properties and multiple modal data, and generate the air bearing foot stiffness corresponding to each air intake data.

[0118] The determination module 15 is used to determine the fitted surface based on multiple intake data and the corresponding air bearing stiffness of the multiple intake data.

[0119] The second acquisition module 16 is used to acquire the air bearing stiffness corresponding to the target air intake data based on the fitted surface.

[0120] In one embodiment of the present invention, the assembly component further includes a hammer and an acceleration sensor. The acceleration sensor is disposed on the working component and is used to collect a first acceleration signal generated when the working component is excited by the hammer. The first generation module 11 is specifically used to receive the first acceleration signal sent by the acceleration sensor through a data acquisition system; generate first test data based on the first acceleration signal; perform finite element analysis on the working component to simulate the simulated properties of the working component and obtain the first simulation data of the working component; and adjust the simulated properties according to the first test data and the first simulation data to generate the material properties of the working component.

[0121] In one embodiment of the present invention, the modal data includes mode shapes and natural frequencies, the adjustment component includes a pressure regulating device and a length measuring device, and the second generation module 13 is specifically used to adjust the pressure regulating device to obtain multiple intake air pressures; to measure multiple air film thicknesses through the length measuring device; to collect a second acceleration signal generated when the working component is excited by a force hammer through an acceleration sensor under each intake air pressure and air film thickness; to receive the second acceleration signal sent by the acceleration sensor through a data acquisition system; and to generate second test data based on the second acceleration signal, wherein the second test data is the mode shape and natural frequency corresponding to each intake data.

[0122] In one embodiment of the present invention, the third generation module 14 is specifically used to assign material properties to the working component, preset the air bearing stiffness for the air bearing foot, and perform finite element analysis on the working component, the air bearing foot and the working platform support to generate second simulation data; and generate the air bearing stiffness corresponding to each air intake data according to the second test data and the second simulation data.

[0123] In one embodiment of the present invention, Figure 7 This is a schematic diagram of the structure of a determining module provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the determining module 15 includes: a first generating submodule 151, an obtaining submodule 152, a second generating submodule 153, and a determining submodule 154.

[0124] The first generation submodule 151 is used to select the first intake data from multiple intake data to perform constraint modal testing on the working component, air bearing foot and working platform support, and generate the first modal data corresponding to the first intake data.

[0125] The acquisition submodule 152 is used to obtain the equivalent spring stiffness data corresponding to the first intake data from the fitted surface.

[0126] The second generation submodule 153 is used to perform simulation analysis on the working components, air-bearing feet and working platform supports with equivalent spring stiffness data, and generate second modal data.

[0127] The determination submodule 154 is used to determine the fitted surface based on the first modal data and the second modal data.

[0128] In one embodiment of the present invention, the first modal data includes a first mode shape and a first natural frequency, and the second modal data includes a second mode shape and a second natural frequency. The determining submodule 154 is specifically used to determine whether the first mode shape and the second mode shape are consistent, and whether the difference between the first natural frequency and the second natural frequency is less than a set threshold. If it is determined that the first mode shape and the second mode shape are consistent, and the difference between the first natural frequency and the second natural frequency is less than the set threshold, then the fitting surface is determined based on multiple air intake data of the second modal data and the air bearing stiffness corresponding to the multiple air intake data.

[0129] In the technical solution provided by this invention, the stiffness of the air-bearing foot is simulated using a test component mounted on a machine tool. The test component includes an assembly component, an adjustment component, the air-bearing foot, and a work platform support. The assembly component includes a work component. Free modal testing is performed on the work component to generate its material properties. Multiple air intake data are obtained by adjusting the adjustment component. Constrained modal testing is performed on the work component, the air-bearing foot, and the work platform support to generate modal data corresponding to each air intake data point. The air intake data includes air intake pressure and air film thickness. Based on the material properties and multiple modal data, constrained modal simulation analysis is performed on the work component, the air-bearing foot, and the work platform support to generate the stiffness of the air-bearing foot corresponding to each air intake data point. A fitting surface is determined based on the multiple air intake data points and the corresponding air-bearing foot stiffness. The air-bearing foot stiffness corresponding to the target air intake data is obtained based on the fitting surface. Predicting the air-bearing foot stiffness using the fitting surface improves simulation efficiency. Furthermore, the surface is verified and its parameters are adjusted using the target air intake data, improving the accuracy of the stiffness data predicted by the fitting surface.

[0130] The air-bearing foot stiffness acquisition device provided in this embodiment can be used to achieve the above. Figure 1 The method for obtaining the stiffness of the air-bearing foot is described in detail in the above-described embodiment of the method for obtaining the stiffness of the air-bearing foot, and will not be repeated here.

[0131] This invention provides a storage medium that includes a stored program. When the program runs, it controls the device where the storage medium is located to execute the steps of the above-described method for obtaining the stiffness of the air buoyancy foot. For a detailed description, please refer to the above-described method for obtaining the stiffness of the air buoyancy foot.

[0132] This invention provides a computer device including a memory and a processor. The memory is used to store information including program instructions, and the processor is used to control the execution of the program instructions. When the program instructions are loaded and executed by the processor, they implement the steps of the above-described method for obtaining the stiffness of the air buoyancy foot. For a detailed description, please refer to the above-described method for obtaining the stiffness of the air buoyancy foot.

[0133] Figure 8 This is a schematic diagram of a computer device provided in an embodiment of the present invention. Figure 8 As shown, the computer device 20 in this embodiment includes a processor 21, a memory 22, and a computer program 23 stored in the memory 22 and executable on the processor 21. When the processor 21 executes the computer program 23, it implements the method for obtaining the stiffness of the air buoyancy foot in this embodiment. To avoid repetition, these details are not elaborated here. Alternatively, when the processor 21 executes the computer program, it implements the functions of each model / unit in the device for obtaining the stiffness of the air buoyancy foot in this embodiment. To avoid repetition, these details are not elaborated here.

[0134] Computer device 20 includes, but is not limited to, processor 21 and memory 22. Those skilled in the art will understand that... Figure 8 This is merely an example of computer device 20 and does not constitute a limitation on computer device 20. It may include more or fewer components than shown, or combine certain components, or different components. For example, computer device may also include input / output devices, network access devices, buses, etc.

[0135] The processor 21 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0136] The memory 22 can be an internal storage unit of the computer device 20, such as a hard disk or RAM of the computer device 20. The memory 22 can also be an external storage device of the computer device 20, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the computer device 20. Furthermore, the memory 22 can include both internal and external storage units of the computer device 20. The memory 22 is used to store computer programs and other programs and data required by the computer device. The memory 22 can also be used to temporarily store data that has been output or will be output.

[0137] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0138] In the embodiments provided by this invention, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0139] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0140] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0141] The integrated units implemented as software functional units described above can be stored in a computer-readable storage medium. These software functional units, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0142] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for obtaining the stiffness of an air-bearing foot, characterized in that, The stiffness of the air-bearing foot is simulated using a test assembly mounted on a machine tool. The test assembly includes an assembly component, an adjustment component, the air-bearing foot, and a work platform support. The assembly component includes a working component. The method for obtaining the stiffness includes: Free modal testing is performed on the working component to generate the material properties of the working component; Multiple intake data points are obtained by adjusting the aforementioned tuning components; Constrained modal tests are performed on the working components, the air-bearing feet, and the working platform support to generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness; Based on the material properties and multiple modal data, constrained modal simulation analysis is performed on the working component, the air-bearing foot and the working platform support to generate the air-bearing foot stiffness corresponding to each air intake data. The fitted surface is determined based on multiple intake data and the corresponding air bearing stiffness of the multiple intake data. Based on the fitted surface, obtain the air bearing stiffness corresponding to the target air intake data; The step of determining the fitted surface based on multiple intake data and the corresponding air bearing stiffness includes: From the multiple intake data, the first intake data is selected to perform constraint modal testing on the working component, the air float, and the working platform support, thereby generating the first modal data corresponding to the first intake data; Obtain the equivalent spring stiffness data corresponding to the first intake data from the fitted surface; Simulation analysis is performed on the working component, the air-bearing foot, and the working platform support, which are given the equivalent spring stiffness data, to generate second modal data; The fitted surface is determined based on the first modal data and the second modal data.

2. The acquisition method according to claim 1, characterized in that, The assembly assembly also includes a force hammer and an acceleration sensor. The acceleration sensor is disposed on the working assembly and is used to collect a first acceleration signal generated when the working assembly is excited by the force hammer. The step of performing free modal testing on the working assembly to generate the material properties of the working assembly includes: The data acquisition system receives the first acceleration signal sent by the acceleration sensor. First test data is generated based on the first acceleration signal; Finite element analysis is performed on the working component to simulate its properties and obtain the first simulation data of the working component. The simulation properties are adjusted based on the first test data and the first simulation data to generate the material properties of the working component.

3. The acquisition method according to claim 2, characterized in that, The modal data includes mode shapes and natural frequencies; the tuning assembly includes a pressure regulating device and a length measuring device; the constrained modal testing of the working assembly, the air bearing foot, and the working platform support to generate modal data corresponding to each air intake data includes: Adjust the pressure regulating device to obtain multiple intake air pressures; Multiple air film thicknesses were measured using the length measuring device. At each intake air pressure and air film thickness, the acceleration sensor collects the second acceleration signal generated when the working component is excited by the force hammer. The data acquisition system receives the second acceleration signal sent by the acceleration sensor. Second test data is generated based on the second acceleration signal, wherein the second test data is the mode shape and natural frequency corresponding to each intake data.

4. The acquisition method according to claim 3, characterized in that, Based on the material properties and multiple modal data, constrained modal simulation analysis is performed on the working component, the air-bearing foot, and the working platform support to generate the air-bearing foot stiffness corresponding to each air intake data, including: Assign the material properties to the working component, preset the air-floating foot stiffness to the air-floating foot, and perform finite element analysis on the working component, the air-floating foot, and the working platform support to generate second simulation data; Based on the second test data and the second simulation data, the air bearing stiffness corresponding to each air intake data is generated.

5. The acquisition method according to claim 1, characterized in that, The first modal data includes a first mode shape and a first natural frequency, and the second modal data includes a second mode shape and a second natural frequency. Determining the fitted surface based on the first modal data and the second modal data includes: Determine whether the first mode shape and the second mode shape are consistent, and whether the difference between the first natural frequency and the second natural frequency is less than a set threshold; If it is determined that the first mode shape and the second mode shape are the same, and the difference between the first natural frequency and the second natural frequency is less than a set threshold, then the fitted surface is determined based on multiple air intake data of the second mode data and the air bearing stiffness corresponding to the multiple air intake data.

6. A testing component, applied to the method for obtaining the stiffness of an air-bearing foot as described in claim 1, characterized in that, include: The work platform support is mounted on the bed; the air-bearing feet are mounted on the bed. The adjustment and testing components are mounted on the bed frame; The bed frame supports the working components; the work platform support is mounted on the bed frame. A force hammer is mounted on the machine bed; an acceleration sensor is mounted on the working assembly.

7. A device for obtaining the stiffness of an air-floating foot, characterized in that, The stiffness of the air-bearing foot is simulated using a test assembly mounted on a machine tool. The test assembly includes an assembly component, an adjustment component, the air-bearing foot, and a work platform support. The assembly component includes a working component. The acquisition device includes: The first generation module is used to perform free modal testing on the working component and generate the material properties of the working component; The first acquisition module is used to acquire multiple intake data by adjusting the adjustment component; The second generation module is used to perform constraint modal testing on the working component, the air-bearing foot and the working platform support, and generate modal data corresponding to each air intake data, wherein the air intake data includes air intake pressure and air film thickness. The third generation module is used to perform constrained modal simulation analysis on the working component, the air-floating foot and the working platform support based on the material properties and multiple modal data, and generate the air-floating foot stiffness corresponding to each air intake data. The determination module is used to determine the fitting surface based on multiple air intake data and the corresponding air bearing stiffness of the multiple air intake data. The second acquisition module is used to acquire the air bearing stiffness corresponding to the target air intake data based on the fitted surface. The determining module includes: a first generating submodule, an obtaining submodule, a second generating submodule, and a determining submodule; The first generation submodule is used to select first intake data from multiple intake data to perform constraint modal testing on the working component, the air float and the working platform support, and generate first modal data corresponding to the first intake data; The acquisition submodule is used to acquire the equivalent spring stiffness data corresponding to the first intake data from the fitted surface; The second generation submodule is used to perform simulation analysis on the working component, the air-floating foot and the working platform support to which the equivalent spring stiffness data is assigned, and to generate second modal data. A determination submodule is used to determine the fitted surface based on the first modal data and the second modal data.

8. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the method for obtaining the stiffness of the air-bearing foot as described in any one of claims 1 to 5.

9. A computer device comprising a memory and a processor, the memory for storing information including program instructions, and the processor for controlling the execution of the program instructions, characterized in that, When the program instructions are loaded and executed by the processor, they implement the steps of the method for obtaining the stiffness of the air-bearing foot as described in any one of claims 1 to 5.

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