An analysis and correction method of the introduced error based on the additional connection link of the vibration isolation device

Abstract

A method for analyzing and correcting the introduced errors of the additional connection links of the vibration isolation device is proposed. By comprehensively analyzing the introduced error parameters of each connection link, such as the spacecraft unloading connection introduced error, the vibration isolation device unloading device connection introduced error, the background noise error, and the measurement cable connection introduced error, the influence of each introduced error on the micro-vibration environment is comprehensively evaluated, and then the vibration isolation efficiency of the vibration isolation device and the micro-vibration environment are evaluated, so as to ensure the correctness of the evaluation of the micro-vibration environment of sensitive components.

Description

Technical Field

[0001] The invention relates to an introduced error analysis and correction method based on an additional connection link of a vibration isolation device, and belongs to the field of on-board sensitive component testing and analysis. Background Art

[0002] In order to meet the requirement of the sensitive components on the satellite to have a micro-vibration environment with an acceleration root mean square of no more than 2mg or even lower, the vibration isolation device adopts a low-stiffness and high-damping vibration isolation design. The first six frequencies of the vibration isolator and the sensitive component assembly are generally less than 5Hz. For this vibration isolation device, when verifying the vibration isolation efficiency of the vibration isolation device in the whole satellite environment, it is greatly affected by the various connection links of the test system (such as the sensitive component unloading device, the test cable on the sensitive component, etc.). If the error introduced by the connection link of the test system is not considered, the acceleration root mean square response of the component after vibration isolation will be much greater than the environmental requirements of the sensitive component. This parameter cannot be used to determine whether the micro-vibration environment after vibration isolation by the vibration isolation device meets the requirements of the sensitive component. For example, in a satellite test, without considering the influence of the error introduced by the connection link, the acceleration root mean square response of the sensitive component in each working condition in the test test was 2.5~3mg, which was greater than the requirement of the sensitive component that the acceleration root mean square was less than 2mg, which had a great impact on the vibration isolation performance evaluation of the vibration isolation device.

[0003] At present, error analysis in spacecraft micro-vibration tests is mainly based on uncertainty factor analysis and measurement system error analysis. The uncertainty of micro-vibration tests is mainly carried out from various aspects such as product status, individual differences in disturbing components, measurement errors, and differences in the earth-sky environment. Measurement errors are generally carried out using quantitative methods, and other uncertainties are generally evaluated qualitatively. At the same time, since the vibration isolation frequency of the disturbing components is high, generally above 10Hz, the error terms introduced in the connecting links of the test system during the test will not affect the vibration isolation efficiency evaluation. Therefore, quantitative analysis of the errors introduced in the connecting links of the test system is generally not carried out.

[0004] In the verification of the ground micro-vibration test of spacecraft, in order to simulate the on-orbit flight state of the spacecraft and the components of the vibration isolation device, it is necessary to add a corresponding test system to simulate the on-orbit flight state of the spacecraft and the vibration isolation product. Compared with the uncertainty analysis factors in the previous micro-vibration test, due to the low vibration isolation frequency and high vibration isolation requirements of the vibration isolation device, the connection links of the test system such as the spacecraft boundary simulation and the boundary simulation of the vibration isolation device components will affect the vibration isolation performance of the vibration isolation device. If the influence of the error introduced by the above connection links is not considered, it will seriously affect the vibration isolation efficiency of the vibration isolation device and the evaluation of the micro-vibration environment adaptability of the sensitive components. Therefore, in view of the influence of the error introduced by each connection link in the evaluation of the vibration isolation efficiency of the vibration isolation device, it is necessary to quantitatively analyze the error terms and their influence degree of each connection link of the test system, and carry out the vibration isolation efficiency and micro-vibration environment evaluation after comprehensively considering the introduced errors. Summary of the invention

[0005] The technical problem solved by the present invention is: in view of the deficiency of quantitative analysis of error introduced by the connection link of the test system in the vibration isolation efficiency evaluation of the vibration isolation device in the current prior art, an error introduction analysis and correction method based on the additional connection link of the vibration isolation device is proposed.

[0006] The present invention solves the above technical problems by the following technical solutions:

[0007] A method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device, the steps are as follows:

[0008] (1) Analyze the dynamic characteristics of the vibration isolation device and the assembly of sensitive components in the device;

[0009] (2) Design a test plan for the vibration isolation efficiency system of the vibration isolation device;

[0010] (3) Analyze the error terms of the additional connection links of the vibration isolation device;

[0011] (4) Establish an error analysis model;

[0012] (5) Conduct error term test on the additional connection link of the vibration isolation device;

[0013] (6) Analyze and correct the errors introduced in the connection link based on the test results obtained in step (5).

[0014] In step (1), the specific steps of the kinetic characteristics analysis are as follows:

[0015] (1-1) Analyze the dynamic characteristics of the vibration isolation device;

[0016] (1-2) Conduct dynamic analysis of the assembly of the vibration isolation device and sensitive components to identify the stiffness characteristics of the assembly;

[0017] (1-3) Conduct modal tests on the vibration isolation device and the assembly to obtain the stiffness characteristics of the vibration isolation device and the assembly;

[0018] (1-4) According to the experiment of step (1-3), the dynamic characteristic parameters of the vibration isolation device and the sensitive components are determined through simulation analysis and experimental verification, and the first-order frequency f is recorded.

[0019] In step (2), the specific steps of the experimental design are as follows:

[0020] (2-1) Designing a vibration isolation efficiency scheme for the vibration isolation device based on the dynamic analysis results of the vibration isolation device and the sensitive component assembly in step (1);

[0021] (2-2) Determine the method for simulating the on-orbit flight status of spacecraft and vibration isolation devices;

[0022] (2-3) Construct a vibration isolation efficiency test verification system for the vibration isolation device and complete the test plan design.

[0023] In step (3), the specific steps of error term analysis are:

[0024] (3-1) List the components or parts in the vibration isolation efficiency test verification system that are connected to the sensitive components and the vibration isolation device;

[0025] (3-2) Perform dynamic analysis on the components or parts obtained in step (3-1), obtain the connection stiffness between each connection link and the sensitive component, and record the first-order frequencies f1, f2, f3, ..., f m , check whether the error introduced by the connection link affects the vibration isolation device;

[0026] (3-3) For connection components or parts whose connection stiffness cannot be obtained through simulation analysis, their stiffness parameters are obtained through experimental methods and screened.

[0027] In the step (3-2), the screening criteria required are:

[0028] If f i ≤f+Δf, the error introduced must be considered, and this component is denoted as A i ;

[0029] If f i >f+Δf, the error introduced by the connection component is not considered;

[0030] Wherein, i represents the i-th connected component, i=1,2,3,…,m, and Δf is the first-order frequency half-power bandwidth of the isolator and sensitive component combination.

[0031] In step (4), the specific steps of establishing the error analysis model are:

[0032] (4-1) The acceleration response of each connection link is introduced into the error term as ε1, ε2, ε3, ....ε i ;

[0033] (4-2) The acceleration vibration of each error term is described by a single-frequency periodic simple harmonic vibration, specifically:

[0034] ε1sin(ω1t+φ1),ε2sin(ω2t+φ2),ε3sin(ω3t+φ3),....

[0035] In the formula, ω, φ are the vibration period and initial phase respectively;

[0036] (4-3) The error terms introduced into each connection link are synthesized according to the simple harmonic oscillation synthesis method to obtain the comprehensive error expression:

[0037] ε=ε1sin(ω1t+φ1)+ε2sin(ω2t+φ2)+ε3sin(ω3t+φ3)+....

[0038] In the formula, the comprehensive error acceleration response amplitude is

[0039] In step (5), the specific steps of the error term test are as follows:

[0040] (5-1) Testing the connection components or parts that cannot be simulated and analyzed to obtain the connection stiffness in step (3-3), obtaining error terms, and screening them, and the screening criteria are the same as those in step (3-2);

[0041] (5-2) According to the error term of the connection link in step (3) and the error term obtained after the test in step (5-1), the error parameter test of each error term is performed to obtain the error parameter of each error term;

[0042] (5-3) Determine the influence of the error term based on the obtained error term parameters. If the error term parameter is greater than 10% of the allowable value after the vibration isolator is isolated, analyze the influence of the error term on the vibration isolation efficiency. If the acceleration root mean square response after the vibration isolator is isolated is required to be no more than 2 mg, then when the error term root mean square response is greater than 0.2 mg, analyze the influence of the error term on the vibration isolation efficiency.

[0043] (5-4) The error analysis model established in step (4) is used to calculate the comprehensive error parameters introduced into the connection link between the vibration isolator and the sensitive component.

[0044] In step (6), the specific steps of analyzing and correcting the error introduced in the connection link are:

[0045] (6-1) Calculate the comprehensive error introduced by the connection environment based on the model obtained in step (4);

[0046] (6-2) Correcting the acceleration response of the sensitive device to obtain the corrected actual vibration response;

[0047] (6-3) Perform multiple test experiments according to steps (4), (5), and (6-2) to obtain the vibration response on the sensor respectively. The calculation method for determining the acceleration vibration response on the sensitive device is as follows:

[0048]

[0049] In the formula, n represents the number of times the test data is obtained;

[0050] (6-4) Based on the acceleration response of the corrected sensitive component, the vibration isolation efficiency of the vibration isolation device and the adaptability of the sensitive device to the micro-vibration environment are evaluated and analyzed and confirmed.

[0051] The advantages of the present invention compared with the prior art are:

[0052] (1) The present invention provides an analysis and correction method for the introduced error of the additional connection link of the vibration isolation device. According to the influence of the error introduced by each connection link of the test system, the micro-vibration environment after vibration isolation is divided into two parts: the real environment + the error introduced by the connection link. By accurately identifying and testing the error terms and errors introduced by the connection link, the real environment after vibration isolation by the vibration isolation device is obtained, which effectively solves the influence of the error introduced by the connection link of the test system on the vibration isolation efficiency evaluation.

[0053] (2) The present invention analyzes and experimentally determines the error terms introduced into the connection links of the test system, and quantitatively tests or calculates the error terms, thereby achieving the acquisition of the errors introduced into the connection links of the vibration isolator and the sensitive components, and providing a basis for quantitatively evaluating the impact of the errors introduced into the connection links, the vibration isolation efficiency of the vibration isolation device, and the adaptability of the sensitive components to the micro-vibration environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A flow chart of an error analysis and correction method for introducing an additional connection link in the vibration isolation efficiency evaluation of the vibration isolator provided by the invention;

[0055] Figure 2 A schematic diagram of a vibration isolation efficiency test system for a vibration isolation device provided for the invention;

[0056] Figure 3 A schematic diagram of the PSD response of the entire star boundary at around 4 Hz provided for the invention; DETAILED DESCRIPTION

[0057] A method for error analysis and correction based on the additional connection link of the vibration isolation device, such as Figure 1 As shown, it is applicable to the vibration isolation device to introduce error analysis, testing and correction to the connection link in the vibration isolation efficiency evaluation. The specific method steps are as follows:

[0058] (1) Analyze the dynamic characteristics of the vibration isolation device and the assembly of sensitive components in the device;

[0059] The specific steps of dynamic characteristics analysis are as follows:

[0060] (1-1) Analyze the dynamic characteristics of the vibration isolation device;

[0061] (1-2) Conduct dynamic analysis of the assembly of the vibration isolation device and sensitive components to identify the stiffness characteristics of the assembly;

[0062] (1-3) Conduct modal tests on the vibration isolation device and the assembly to obtain the stiffness characteristics of the vibration isolation device and the assembly;

[0063] (1-4) According to the experiment of step (1-3), the dynamic characteristic parameters of the vibration isolation device and the sensitive components are determined through simulation analysis and experimental verification, and the first-order frequency f is recorded;

[0064] (2) Design a test plan for the vibration isolation efficiency system of the vibration isolation device;

[0065] The specific steps of experimental design are as follows:

[0066] (2-1) Designing a vibration isolation efficiency scheme for the vibration isolation device based on the dynamic analysis results of the vibration isolation device and the sensitive component assembly in step (1);

[0067] (2-2) Determine the method for simulating the on-orbit flight status of spacecraft and vibration isolation devices;

[0068] (2-3) Construct a vibration isolation efficiency test verification system for the vibration isolation device and complete the test plan design;

[0069] (3) Analyze the error terms of the additional connection links of the vibration isolation device;

[0070] The specific steps of error term analysis are as follows:

[0071] (3-1) List the components or parts in the vibration isolation efficiency test verification system that are connected to the sensitive components and the vibration isolation device;

[0072] (3-2) Perform dynamic analysis on the components or parts obtained in step (3-1), obtain the connection stiffness between each connection link and the sensitive component, and record the first-order frequencies f1, f2, f3, ..., f m , check whether the error introduced by the connection link affects the vibration isolation device;

[0073] Among them, the screening criteria required are:

[0074] If f i ≤f+Δf, the error introduced must be considered, and this component is denoted as A i ;

[0075] If f i >f+Δf, the error introduced by the connection component is not considered;

[0076] Where i represents the i-th connected component, i = 1, 2, 3, ..., m, Δf is the first-order frequency half-power bandwidth of the isolator and sensitive component combination;

[0077] (3-3) For connection components or parts whose connection stiffness cannot be obtained through simulation analysis, their stiffness parameters are obtained through test methods and screened;

[0078] (4) Establish an error analysis model;

[0079] Among them, the specific steps of establishing the error analysis model are:

[0080] (4-1) The acceleration response of each connection link is introduced into the error term as ε1, ε2, ε3, ....ε i ;

[0081] (4-2) The acceleration vibration of each error term is described by a single-frequency periodic simple harmonic vibration, specifically:

[0082] ε1sin(ω1t+φ1),ε2sin(ω2t+φ2),ε3sin(ω3t+φ3),....

[0083] In the formula, ω, φ are the vibration period and initial phase respectively;

[0084] (4-3) The error terms introduced into each connection link are synthesized according to the simple harmonic oscillation synthesis method to obtain the comprehensive error expression:

[0085] ε=ε1sin(ω1t+φ1)+ε2sin(ω2t+φ2)+ε3sin(ω3t+φ3)+....

[0086] In the formula, the comprehensive error acceleration response amplitude is

[0087] (5) Conduct error term test on the additional connection link of the vibration isolation device;

[0088] The specific steps of the error term test are as follows:

[0089] (5-1) Testing the connection components or parts that cannot be simulated and analyzed to obtain the connection stiffness in step (3-3), obtaining error terms, and screening them, and the screening criteria are the same as those in step (3-2);

[0090] (5-2) According to the error term of the connection link in step (3) and the error term obtained after the test in step (5-1), the error parameter test of each error term is performed to obtain the error parameter of each error term;

[0091] (5-3) Determine the influence of the error term based on the obtained error term parameters. If the error term parameter is greater than 10% of the allowable value after the vibration isolator is isolated, analyze the influence of the error term on the vibration isolation efficiency. If the acceleration root mean square response after the vibration isolator is isolated is not greater than 2mg, then when the error term root mean square response is greater than 0.2mg, analyze the influence of the error term on the vibration isolation efficiency.

[0092] (5-4) calculating the comprehensive error parameters introduced into the connection link between the vibration isolator and the sensitive component through the error analysis model established in step (4);

[0093] (6) Analyze and correct the errors introduced in the connection link according to the test results obtained in step (5), specifically:

[0094] The specific steps for analyzing and correcting the errors introduced in the connection link are as follows:

[0095] (6-1) Calculate the comprehensive error introduced by the connection environment based on the model obtained in step (4);

[0096] (6-2) Correcting the acceleration response of the sensitive device to obtain the corrected actual vibration response;

[0097] (6-3) Perform multiple test experiments according to steps (4), (5), and (6-2) to obtain the vibration response on the sensor respectively. The calculation method for determining the acceleration vibration response on the sensitive device is as follows:

[0098]

[0099] In the formula, n represents the number of times the test data is obtained;

[0100] (6-4) Based on the acceleration response of the corrected sensitive component, evaluate the vibration isolation efficiency of the vibration isolation device and the adaptability of the sensitive device to the micro-vibration environment, and conduct analysis and confirmation;

[0101] The following is further described according to specific embodiments:

[0102] In the current embodiment, in view of the deficiency of quantitative analysis of errors introduced in the connection link of the test system in the vibration isolation efficiency evaluation of the vibration isolation device, an error analysis and correction method for introducing additional connection links in the vibration isolation efficiency evaluation of the vibration isolation device is proposed, and the steps are as follows:

[0103] (1) Dynamic characteristics analysis of vibration isolation device and sensitive component assembly

[0104] a) Dynamic characteristics analysis of vibration isolation device;

[0105] b) Dynamic analysis of the assembly of vibration isolation devices and sensitive components to identify the stiffness characteristics of the assembly;

[0106] c) Modal test of vibration isolation device and assembly to obtain the stiffness characteristics of the vibration isolation device and assembly;

[0107] Through simulation analysis and experimental verification, the dynamic characteristic parameters of the vibration isolation device and sensitive components are determined, and the first-order frequency is recorded as f;

[0108] (2) Design of system-level test plan for vibration isolation efficiency of vibration isolation device

[0109] a) Design the vibration isolation efficiency scheme of the vibration isolation device based on the dynamic characteristics analysis or test results of the vibration isolation device and sensitive component assembly;

[0110] b) Clarify the simulation methods of on-orbit flight status of spacecraft, vibration isolation devices, etc.;

[0111] c) Constructing a vibration isolation device vibration isolation efficiency test verification system, as in the embodiment Figure 2 shown.

[0112] (3) Analysis of error terms introduced into the connection link

[0113] a) List the components or parts in the test system that are connected to the sensitive components and their vibration isolation devices;

[0114] b) Carry out mechanical analysis on the connecting parts or components to obtain the connection stiffness of each connection link and the sensitive component. The first-order frequencies of the connection links are recorded as f1, f2, f3, ..., f m (m is the number of components connected to the vibration isolator and its sensitive components). Use the following criteria to screen whether the error introduced by the connection link has an impact on the vibration isolation device:

[0115] f i ≤f+Δf, then the error introduced needs to be considered, and the component is denoted as A i ;

[0116] f i >f+Δf, then the error introduced by the connection component can be ignored;

[0117] i represents the i-th connected component, i=1,2,3,…,m, Δf is the first-order frequency half-power bandwidth of the vibration isolator and sensitive component combination.

[0118] For connection components or parts that cannot be simulated and analyzed to obtain the connection stiffness, their stiffness parameters will be obtained through test methods and screened according to condition b);

[0119] (4) Establish error analysis model

[0120] a) The acceleration response of the error term introduced in each connection link is recorded as ε1, ε2, ε3, ....;

[0121] b) The error term introduced by each connection link is generally a single-frequency periodic simple harmonic vibration. The acceleration vibration of each error term can be described as:

[0122] ε1sin(ω1t+φ1),ε2sin(ω2t+φ2),ε3sin(ω3t+φ3),....

[0123] ω, φ are the vibration period and initial phase respectively;

[0124] c) The comprehensive error of the error term introduced by each connection link is synthesized according to the simple resonance synthesis method and can be expressed as:

[0125] ε=ε1sin(ω1t+φ1)+ε2sin(ω2t+φ2)+ε3sin(ω3t+φ3)+....

[0126] The synthesized comprehensive error acceleration response amplitude can be expressed as:

[0127] (5) Connection link error test

[0128] a) Test the stiffness of components or parts whose connection stiffness cannot be obtained through simulation analysis, and screen their influence according to the requirements of step 3) c);

[0129] b) According to the connection link error terms analyzed in step 3) and the error terms obtained through experiments in step 5) a), test the error parameters of each error term to obtain the error parameters of each error term. The specific method is as follows:

[0130] i. Test each error term or combination of error terms to obtain error parameters of each error term or multiple combination of error terms, such as:

[0131] Test item 1: A1, A2, test results are ε1, ε2

[0132] Test item 2: A1+A3, test result is ε 13

[0133] Test item 3: A2+A4, test result is ε 24

[0134] Test item 4: A3+A5, test result is ε 35

[0135] Test item 5: A1+A3+A6, test result is ε 136

[0136] …

[0137] ii. Use the error synthesis method to calculate the error parameters of each error term, such as:

[0138] Test item 1: A1, A2, the errors of error item 1 and error item 2 are ε1, ε2

[0139] Test item 2: A1+A3, the error of error item 3 is:

[0140] Test item 3: A2+A4, the error of error item 4 is:

[0141] Test item 4: A3+A5, the error of error item 5 is:

[0142] Test item 5: A1+A3+A6, the error of error item 6 is:

[0143] …

[0144] iii. To introduce an error term into each connection link, multiple measurements can be performed and the mean value can be calculated as the error introduced into the connection link, such as:

[0145]

[0146] ε 1-i ,i=1,2,3,...,n is the i-th test result of error term 1, n is the number of measurements;

[0147] c) Determine the influence of the error term. When the error term parameter is greater than 10% of the allowable value after vibration isolation by the vibration isolator, the influence of the error term on the vibration isolation efficiency shall be considered. For example, if the acceleration root mean square response after vibration isolation by the vibration isolator is required to be no greater than 2 mg, then when the error term root mean square response is greater than 0.2 mg, its influence on the vibration isolation efficiency shall be analyzed.

[0148] d) Calculate the comprehensive error parameters introduced in the connection between the vibration isolator and the sensitive component according to step 4);

[0149] (6) Error analysis and correction introduced by the connection environment

[0150] a) according to the introduced errors of each connection link obtained through the test in step 4), step 5) calculates the comprehensive error introduced by the connection environment;

[0151] b) The acceleration response on the sensitive device during the test is a1. After removing the error terms introduced by each connection environment, the acceleration response on the sensor is corrected. The actual vibration response on the sensitive device after correction should be

[0152] c) Carry out multiple tests according to step 4), step 5) and step 6) (b) to obtain the vibration response during the sensitive period. …, then the acceleration vibration response on the sensitive device can be expressed as n represents the number of times the test data is obtained.

[0153] d) Based on the acceleration response of the corrected sensitive components, evaluate the vibration isolation efficiency of the vibration isolation device and analyze and confirm the adaptability of the sensitive components to the micro-vibration environment.

[0154] As the accuracy and real-time requirements of precise orbit determination of a certain remote sensing satellite increase, the demand for high-precision accelerometers is becoming more and more urgent. In order to meet the satellite's high-precision acceleration measurement needs, the requirements for the satellite's micro-vibration environment are becoming more and more stringent. The satellite is equipped with a high-precision accelerometer. To ensure the accuracy of the on-orbit measurement data and avoid excessive micro-vibration environment on the satellite causing saturation of the accelerometer, which makes it impossible to achieve high-precision on-orbit acceleration measurement, the on-orbit micro-vibration environment acceleration root mean square is required to be no more than 2mg. To this end, the satellite is equipped with a set of vibration isolation devices to meet the micro-vibration suppression requirements of the accelerometer to ensure that the micro-vibration environment after vibration isolation meets the suppression requirements of the accelerometer.

[0155] During the development, the vibration isolation device was analyzed for introduced errors according to this method. The specific implementation is as follows:

[0156] Through simulation analysis and modal tests, the translational stiffness of the vibration isolation device and accelerometer assembly is about 2Hz, the swing and torsional stiffness is about 4.5Hz, and the half-power bandwidth of the swing is about 1.5Hz. According to the requirements of step 3) of this method, the components below 6Hz in the connection assembly should consider the impact on the vibration isolation device;

[0157] In order to verify the vibration isolation efficiency of the vibration isolation device components on the whole satellite and whether the micro-vibration environment after vibration isolation meets the requirements, a vibration isolation system was built. Figure 2 The test verification system shown.

[0158] According to step (3) of this method, each connection is analyzed and confirmed, and simulation analysis and testing are performed. The main connection components that affect the vibration isolation device are:

[0159] 1) Accelerometer suspension spring, the affected frequency domain is about 0.2Hz;

[0160] 2) The vibration isolation component is unloaded, and the impact frequency is about 4Hz, such as Figure 3 As shown;

[0161] 3) The connection cable for measurement has an impact frequency of about 1 Hz;

[0162] 4) Environmental noise.

[0163] Through the above identified error terms, each error term is tested individually or in combination, and the root mean square error of each error term is obtained:

[0164] 1) Accelerometer suspension spring: the acceleration root mean square error is about 1 mg;

[0165] 2) Unloading device of vibration isolation component: the root mean square error of acceleration is about 2mg;

[0166] 3) Measurement system connecting cable: the root mean square error of acceleration is about 0.7mg;

[0167] 4) Background noise: The root mean square error of acceleration is about 0.2mg.

[0168] According to the provisions of step 5) of this method, the above connection links must all take into account the impact on the vibration isolation device, and according to step 4), the comprehensive error of the above error terms is calculated to be approximately: 2.12 mg

[0169] According to the comprehensive error parameters calculated above, vibration isolation efficiency tests of three working conditions were carried out according to step 6) of this method. The test results are shown in the following table:

[0170] 1) Without considering the influence of comprehensive error, the acceleration root mean square response after vibration isolation is between 2.3 and 2.9 mg, which is greater than the micro-vibration environment requirements of sensitive devices after vibration isolation;

[0171] 2) After considering the influence of comprehensive errors, the acceleration root mean square response after vibration isolation is between 0.8 and 1.9 mg, and the average response is around 1.4 mg, which meets the requirements of sensitive components for micro-vibration environment, indicating that the vibration isolation efficiency of the vibration isolation device meets the use requirements.

[0172] The error introduced in the connection link is due to the error of the ground test system. This error term does not exist in the on-orbit flight. The impact of the introduced error should be analyzed in the ground test evaluation to avoid the impact of such error on the product performance evaluation.

[0173] The acceleration response parameter table of each working condition after vibration isolation is as follows:

[0174] Working conditions Condition 1 Condition 2 Condition 3 Mean Measurement point 1 after vibration isolation 2.89mg 2.5mg 2.26mg 2.55mg Measuring point 1 (after correction) 1.96mg 1.42mg 0.78mg 1.39mg Measurement point 2 after vibration isolation 2.3mg 2.7mg 2.64mg 2.54mg Measuring point 2 (after correction) 0.89mg 1.67mg 1.57mg 1.38mg

[0175] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0176] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device, characterized in that Here are the steps: (1) Analyze the dynamic characteristics of the vibration isolation device and the assembly of sensitive components in the device; (2) Design a test plan for the vibration isolation efficiency system of the vibration isolation device; (3) Analyze the error terms of the additional connection links of the vibration isolation device; (4) Establish an error analysis model; (5) Conduct error term test on the additional connection link of the vibration isolation device; (6) Analyzing and correcting errors introduced into the connection link according to the test results obtained in step (5); Among them, in step (3), the specific steps of error term analysis are: (3-1) List the components or parts in the vibration isolation efficiency test verification system that are connected to the sensitive components and the vibration isolation device; (3-2) Perform dynamic analysis on the components or parts obtained in step (3-1), obtain the connection stiffness between each connection link and the sensitive component, and record the first-order frequencies f1, f2, f3, ..., f m , check whether the error introduced by the connection link affects the vibration isolation device; (3-3) For connection components or parts whose connection stiffness cannot be obtained through simulation analysis, their stiffness parameters are obtained through test methods and screened; In the step (3-2), the screening criteria required are: If f i ≤f+Δf, the error introduced must be considered, and this component is denoted as A i ; If f i >f+Δf, the error introduced by the connection component is not considered; Where i represents the i-th connected component, i = 1, 2, 3, ..., m, Δf is the first-order frequency half-power bandwidth of the isolator and sensitive component combination; In step (4), the specific steps of establishing the error analysis model are: (4-1) The acceleration response of each connection link is introduced into the error term as ε1, ε2, ε3, ..., ε i ; (4-2) The acceleration vibration of each error term is described by a single-frequency periodic simple harmonic vibration, specifically: ε1sin(ω1t+φ1),ε2sin(ω2t+φ2),ε3sin(ω3t+φ3),...,ε i sin(ω i t+φ i ) In the formula, ω, φ are the vibration period and initial phase respectively; (4-3) The error terms introduced into each connection link are synthesized according to the simple harmonic oscillation synthesis method to obtain the comprehensive error expression: ε=ε1sin(ω1t+φ1)+ε2sin(ω2t+φ2)+ε3sin(ω3t+φ3)+....+ε i sin(ω i t+φ i ) In the formula, the comprehensive error acceleration response amplitude is 2. According to claim 1, a method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device is characterized in that: In step (1), the specific steps of the kinetic characteristics analysis are as follows: (1-1) Analyze the dynamic characteristics of the vibration isolation device; (1-2) Conduct dynamic analysis of the assembly of the vibration isolation device and sensitive components to identify the stiffness characteristics of the assembly; (1-3) Conduct modal tests on the vibration isolation device and the assembly to obtain the stiffness characteristics of the vibration isolation device and the assembly; (1-4) According to the experiment of step (1-3), the dynamic characteristic parameters of the vibration isolation device and the sensitive components are determined through simulation analysis and experimental verification, and the first-order frequency f is recorded.

3. The method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device according to claim 2, characterized in that: In step (2), the specific steps of the experimental design are as follows: (2-1) Designing a vibration isolation efficiency scheme for the vibration isolation device based on the dynamic analysis results of the vibration isolation device and the sensitive component assembly in step (1); (2-2) Determine the method for simulating the on-orbit flight status of spacecraft and vibration isolation devices; (2-3) Construct a vibration isolation efficiency test verification system for the vibration isolation device and complete the test plan design.

4. The method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device according to claim 3 is characterized in that: In step (5), the specific steps of the error term test are as follows: (5-1) Testing the connection components or parts that cannot be simulated and analyzed to obtain the connection stiffness in step (3-3), obtaining error terms, and screening them, and the screening criteria are the same as those in step (3-2); (5-2) According to the error term of the connection link in step (3) and the error term obtained after the test in step (5-1), the error parameter test of each error term is performed to obtain the error parameter of each error term; (5-3) Determine the influence of the error term based on the obtained error term parameters. If the error term parameter is greater than 10% of the allowable value after the vibration isolator is isolated, analyze the influence of the error term on the vibration isolation efficiency; (5-4) The error analysis model established in step (4) is used to calculate the comprehensive error parameters introduced into the connection link between the vibration isolator and the sensitive component.

5. The method for analyzing and correcting the introduced error based on the additional connection link of the vibration isolation device according to claim 4 is characterized in that: In step (6), the specific steps of analyzing and correcting the error introduced in the connection link are: (6-1) Calculate the comprehensive error introduced by the connection environment based on the model obtained in step (4); (6-2) Correcting the acceleration response of the sensitive device to obtain the corrected actual vibration response; (6-3) Perform multiple test experiments according to steps (4), (5), and (6-2) to obtain the vibration response on the sensor respectively. The calculation method for determining the acceleration vibration response on the sensitive device is as follows: In the formula, n represents the number of times the test data is obtained; (6-4) Based on the acceleration response of the corrected sensitive component, the vibration isolation efficiency of the vibration isolation device and the adaptability of the sensitive device to the micro-vibration environment are evaluated and analyzed and confirmed.

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