Frequency-variable stiffness and damping identification system and method for magnetorheological elastomer shock absorber

Abstract

The invention discloses a frequency-variable stiffness and damping identification system and method for a magnetorheological elastomer shock absorber, and belongs to the technical field of vibration reduction and isolation. The device comprises a magneto-rheological elastomer shock absorber sweep frequency vibration test module which is used for carrying out sweep frequency test on the device and collecting and recording original data; the test signal preprocessing module is used for receiving original data and performing filtering and noise reduction processing on the signals; the frequency-variable stiffness and damping model construction module is used for constructing a frequency-variable stiffness and damping identification model of the magnetorheological elastomer damper; and the frequency-variable stiffness and damping identification module identifies and outputs the frequency-variable stiffness and damping of the magnetorheological elastomer damper based on the test signal data and the identification model. Based on the simple and universal sweep frequency vibration test of the shock absorber, additional tool design is not needed, the frequency-dependent rigidity and damping characteristics of the device in the broadband range can be identified only through one-time test, and system resonance information is added.

Description

Technical Field

[0001] The invention relates to the technical field of vibration reduction and isolation, and in particular to a frequency-varying stiffness and damping identification system and method for a magnetorheological elastomer vibration absorber. Background Art

[0002] As a key member of intelligent magnetic sensitive composite materials, magnetorheological elastomer has excellent magnetic field controllability. Because it is superior to magnetorheological fluid in anti-settling and sealing performance, magnetorheological elastomer is widely used in the field of vibration reduction and isolation application technology.

[0003] Magnetorheological elastomers are made of a mixture of a rubber solid matrix and ferromagnetic particles, which give magnetorheological elastomer shock absorbers typical viscoelastic behavior, which makes the characterization of their dynamic characteristics complicated and brings challenges to practical applications. The dynamic characteristics of magnetorheological elastomer shock absorbers are affected by factors such as static load, vibration amplitude, temperature and excitation frequency. Among them, frequency-dependent stiffness and damping are important dynamic characteristics of magnetorheological elastomer shock absorbers, which have a significant impact on the response analysis, dynamic modeling and intelligent control of magnetorheological elastomer shock absorption systems. Therefore, it is of great significance to efficiently identify the frequency-dependent stiffness and damping characteristics of magnetorheological elastomer shock absorbers.

[0004] In order to gain a deeper understanding of these frequency-related dynamic characteristics, researchers have proposed some analysis techniques and methods, which can be roughly divided into two categories: ellipse method and vibration scanning method.

[0005] In the ellipse method, MTS testing machines or vibration tables are widely used to evaluate the dynamic stiffness and damping characteristics of magnetorheological elastomer dampers. This method mainly measures the force-displacement hysteresis loop of the device directly through force sensors and displacement sensors, and then uses the ellipse method to calculate the equivalent stiffness and damping coefficient. For example, Sun et al. used an MTS testing machine to test the dynamic characteristics of magnetorheological dampers at frequencies of 0.5, 1, 1.5 and 2 Hz, and evaluated its equivalent stiffness and damping performance through force-displacement hysteresis loops. Yang et al. used a vibration table to determine the effective stiffness of magnetorheological elastomer dampers at frequencies of 1, 2 and 4 Hz using the same analytical method. However, the application range of the ellipse method is limited to the low frequency band, and the test is performed at discrete frequency points. In order to obtain a continuous dynamic stiffness curve over a wide frequency band, a large number of tests and analyses of magnetorheological elastomer dampers at different frequencies are required, which is not only time-consuming but also inefficient. This problem is further exacerbated by the limitations of actual installation and measurement conditions (such as double-end clamping).

[0006] In the vibration scanning method, the exciter (or vibration table) is also widely used to evaluate the equivalent stiffness and damping. This method can provide excitation in a higher frequency range, overcoming the frequency limitation of the elliptic method. It mainly uses sinusoidal frequency sweep excitation, obtains the amplitude-frequency characteristic curve (also called the transmissibility curve) of the system by recording the excitation and response signals (such as acceleration or displacement signals), and then calculates and analyzes the dynamic stiffness and damping parameters of the magnetorheological damper based on the resonance information. For example, Susheelkumar et al. evaluated the transfer characteristics of the magnetorheological damper by applying frequency sweep excitation in the frequency range of 10-80Hz, and then identified its equivalent stiffness and damping information through the transmissibility curve and resonance information. However, this method is calculated based on the resonance peak and resonance frequency information, assuming that the dynamic characteristics are consistent at all frequencies, and ignoring the inherent frequency-related characteristics of the magnetorheological elastomer damper.

[0007] In addition to magnetorheological elastomer vibration reduction devices, other devices based on magnetorheological technology, such as magnetorheological dampers and magnetorheological vibration absorbers, also use the above two methods to evaluate their frequency-related dynamic characteristics. However, these methods have limitations such as low-frequency restrictions, a single test can only identify stiffness and damping at a single point frequency, and cumbersome test system tooling.

[0008] Therefore, it is necessary to provide a frequency-dependent stiffness and damping identification system and method for a magnetorheological elastomer shock absorber. Summary of the invention

[0009] The purpose of the present invention is to provide a frequency-dependent stiffness and damping identification system and method for a magnetorheological elastomer shock absorber, so as to solve the problems in the prior art such as low-frequency limitation, a single test can only identify the stiffness and damping at a single point frequency, and cumbersome tooling of the test system.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] A frequency-dependent stiffness and damping identification system of a magnetorheological elastomer shock absorber, comprising:

[0012] The sweep frequency vibration test module of the magnetorheological elastomer vibration damping device is used to perform sweep frequency test on the device and collect and record the original data;

[0013] A test signal preprocessing module is used to receive raw data and perform signal filtering and noise reduction processing;

[0014] Frequency-dependent stiffness and damping model building module, used to build the frequency-dependent stiffness and damping identification model of magnetorheological elastomer shock absorber;

[0015] The frequency-dependent stiffness and damping identification module identifies and outputs the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber based on the test signal data and identification model.

[0016] Further, the magnetorheological elastomer vibration damping device sweep frequency vibration test module includes: a magnetorheological elastomer vibration damper, a load mass block, an electromagnetic vibration table, a first acceleration sensor, a data acquisition instrument, a computer, a controller, a power amplifier, a second acceleration sensor and a DC power supply;

[0017] Wherein, the second acceleration sensor and the magnetorheological elastomer shock absorber are both arranged above the electromagnetic vibration table; the load mass block is arranged above the magnetorheological elastomer shock absorber; the first acceleration sensor is arranged above the load mass block; the controller, the power amplifier, the data acquisition instrument, the computer and the DC power supply are respectively arranged at intervals on one side of the electromagnetic vibration table;

[0018] The electromagnetic vibration table, the controller, the power amplifier and the computer are connected in sequence by wires; the DC power supply is connected by wires to the magnetorheological elastomer shock absorber; and the first acceleration sensor and the second acceleration sensor are both connected by wires to the data acquisition instrument.

[0019] Furthermore, the first acceleration sensor is used to collect a response acceleration signal, and the second acceleration sensor is used to collect an excitation acceleration signal, and the response acceleration signal and the excitation acceleration signal are synchronously recorded by the data acquisition instrument.

[0020] Furthermore, in the test signal preprocessing module, a bandpass filter is used to eliminate high-frequency and low-frequency noise in the original data.

[0021] Furthermore, in the frequency-variant stiffness and damping model construction module, a device frequency-variant stiffness and damping identification model is established based on a single-degree-of-freedom magnetorheological elastomer shock absorber-load mass system, and the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber are obtained through time-frequency conversion and real and imaginary part analysis.

[0022] Furthermore, the frequency-dependent stiffness and damping identification module identifies the dynamic stiffness and damping at a wide and continuous frequency based on the frequency-dependent stiffness and damping model and the preprocessed test signal.

[0023] A method for identifying frequency-dependent stiffness and damping of a magnetorheological elastomer vibration absorber is applied to a frequency-dependent stiffness and damping identification system of a magnetorheological elastomer vibration absorber. The method comprises:

[0024] S1, imports the pre-processed sweep vibration excitation and response and velocity signal, which are recorded as and Calculate the frequency-dependent function of the excitation-response ratio by Fast Fourier Transform (FFT) analysis

[0025] S2, based on Obtain the frequency-dependent complex function Trr(jω) and calculate its real part Re{Trr(jω)}, imaginary part Im{Trr(jω)} and modulus square |Trr(jω)| 2 ;

[0026] S3, respectively and The frequency-dependent stiffness k(ω) and damping c(ω) of the magnetorheological elastomer shock absorber are calculated and output.

[0027] Furthermore, the derivation process is as follows:

[0028] The motion equation of the magnetorheological elastomer damper-load mass single degree of freedom system is:

[0029]

[0030] Where m is the load mass, ω is the vibration angular frequency, and x is e With x r are the excitation and response displacement signals, respectively, k(ω) and c(ω) are the frequency-dependent stiffness and damping coefficient of the device, respectively;

[0031] Through Laplace transform, equation (1) can be written as:

[0032] X r (s)(ms 2 +c(ω)s+k(ω))=X e (s)(c(ω)s+k(ω)) (2)

[0033] Then the transfer function of system excitation to response displacement (i.e. the inverse of vibration displacement transmissibility) is:

[0034]

[0035] Similarly, the transfer function of system excitation to response acceleration is:

[0036]

[0037] Substituting s = jω into equation (4), we obtain

[0038]

[0039] set up Then formula (5) is expressed as:

[0040]

[0041] The real and imaginary parts of the frequency-dependent complex function Trr(jω) are:

[0042]

[0043]

[0044] From equations (6)-(8), the frequency-dependent stiffness and damping of the device can be obtained as follows:

[0045]

[0046]

[0047] Among them, the real part, imaginary part and modulus square of Trr(jω) can be further obtained by equations (11)-(13):

[0048]

[0049]

[0050]

[0051] In the above formulas (11) to (13), Both ω and ω can be obtained by processing the data of the swept frequency vibration test results. Then, they are substituted into equations (9) and (10) to obtain the frequency-dependent stiffness and damping coefficient of the magnetorheological elastomer shock absorber.

[0052] The present invention has the following beneficial effects:

[0053] 1. The present invention can identify the frequency-dependent stiffness and damping characteristics of the device within a wide frequency range through a single test. It theoretically analyzes the magnetorheological elastomer shock absorber-load mass system model, performs a series of real and imaginary part analysis and transformation on the inverse of the vibration transfer function, establishes a frequency-dependent stiffness and damping model of the magnetorheological elastomer shock absorber, and then measures the device excitation and response acceleration signals based on a simple and universal sweep frequency vibration test system for the shock absorber. The test results can be used to identify the dynamic stiffness and damping under wide and continuous frequencies.

[0054] 2. The present invention proposes a method and system for identifying the frequency-dependent stiffness and damping of a magnetorheological elastomer shock absorber. Based on a simple and universal swept-frequency vibration test of the shock absorber, the frequency-dependent stiffness and damping characteristics of the device within a wide frequency range can be identified in a single test without the need for additional tooling design, and additional system resonance information. In addition, the present invention is universal and general. As long as the actuator can be used for swept-frequency vibration testing, the system and method proposed in the present invention can be used to identify its frequency-dependent stiffness and damping characteristics, not limited to the frequency-dependent stiffness and damping identification of magnetorheological elastomer shock absorbers. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1It is a structural block diagram of the frequency-dependent stiffness and damping identification system and method of the magnetorheological elastomer vibration absorber of the present invention;

[0056] Figure 2 A schematic diagram of a swept frequency vibration test module of a magnetorheological elastomer vibration damper according to an embodiment of the present invention;

[0057] Figure 3 Schematic diagram of the sweep frequency vibration test results of the magnetorheological elastomer vibration absorber according to the embodiment of the present invention;

[0058] Figure 4 It is a schematic diagram of the frequency-dependent characteristic identification result of the magnetorheological elastomer vibration damper according to an embodiment of the present invention;

[0059] Figure 5 A schematic diagram of the frequency-dependent stiffness and damping variation trend of the magnetorheological elastomer vibration absorber according to an embodiment of the present invention;

[0060] Figure 6 It is a schematic diagram of resonance information of a magnetorheological elastomer damper system according to an embodiment of the present invention.

[0061] Among them: 1. first acceleration sensor; 2. load mass block; 3. magnetorheological elastomer shock absorber; 4. second acceleration sensor; 5. electromagnetic vibration table; 6. controller; 7. power amplifier; 8. DC power supply; 9. computer; 10. data acquisition instrument. DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0063] Reference Figure 1 This embodiment provides a frequency-dependent stiffness and damping identification system for a magnetorheological elastomer shock absorber, the system comprising:

[0064] The swept frequency vibration test module of the magnetorheological elastomer vibration damping device is used to perform swept frequency tests on the device and collect and record raw data.

[0065] The test signal preprocessing module is used to receive the original data and perform filtering and noise reduction on the signal; in the test signal preprocessing module, a bandpass filter is used to eliminate high-frequency and low-frequency noise in the original data.

[0066] The frequency-variant stiffness and damping model construction module is used to construct a frequency-variant stiffness and damping identification model of the magnetorheological elastomer shock absorber 3; specifically, in the frequency-variant stiffness and damping model construction module, based on the single-degree-of-freedom magnetorheological elastomer shock absorber-load mass system, a device frequency-variant stiffness and damping identification model is established, and the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber 3 are obtained through time-frequency conversion and real and imaginary part analysis.

[0067] The frequency-dependent stiffness and damping identification module identifies and outputs the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber 3 based on the test signal data and the identification model. Specifically, the frequency-dependent stiffness and damping identification module identifies the dynamic stiffness and damping under wide-band and continuous frequency based on the frequency-dependent stiffness and damping model and the preprocessed test signal.

[0068] In this embodiment, the swept frequency vibration test module of the magnetorheological elastomer vibration damping device includes: a magnetorheological elastomer vibration damper 3, a load mass block 2, an electromagnetic vibration table 5, a first acceleration sensor 1, a data acquisition instrument 10, a computer 9, a controller 6, a power amplifier 7, a second acceleration sensor 4 and a DC power supply 8.

[0069] Among them, the second acceleration sensor 4 and the magnetorheological elastomer shock absorber 3 are both arranged above the electromagnetic vibration table 5; the load mass block 2 is arranged above the magnetorheological elastomer shock absorber 3; the first acceleration sensor 1 is arranged above the load mass block 2; the controller 6, the power amplifier 7, the data acquisition instrument 10, the computer 9 and the DC power supply 8 are respectively arranged at intervals on one side of the electromagnetic vibration table 5.

[0070] The electromagnetic vibration table 5, the controller 6, the power amplifier 7 and the computer 9 are connected in sequence; the DC power supply 8 is connected to the magnetorheological elastomer damper 3 by wire; the first acceleration sensor 1 and the second acceleration sensor 4 are both connected to the data acquisition instrument 10 by wire.

[0071] The first acceleration sensor 1 is used to collect the response acceleration signal, and the second acceleration sensor 4 is used to collect the excitation acceleration signal. The response acceleration signal and the excitation acceleration signal are synchronously recorded by the data acquisition device 10.

[0072] This embodiment takes the frequency-dependent stiffness and damping identification of a shear-type magnetorheological elastomer shock absorber as an example.

[0073] First, build a sweep frequency vibration test system for magnetorheological elastomer shock absorbers, such as Figure 2 As shown, the test system consists of a magnetorheological elastomer damper 3, a DC power supply 8, a load mass block 2, a sweep frequency excitation system (electromagnetic vibration table 5, a controller 6 and a power amplifier 7), two acceleration sensors (a first acceleration sensor 1 and a second acceleration sensor 4), a data acquisition instrument 10 and a computer 9. According to the design target of the device, a sine sweep frequency vibration excitation of 50-180Hz and an amplitude of 0.2g is applied; at the same time, in order to test the device performance under different currents, the DC power supply 8 applies currents of 0A, 0.3A, 0.6A, 0.9A and 1.2A to the device respectively, and the two acceleration sensors respectively collect the system excitation and response acceleration signals, and the data acquisition instrument 10 records them synchronously.

[0074] Secondly, a bandpass filter is used to eliminate high-frequency and low-frequency noise in the original data, thereby obtaining the excitation acceleration signal of the magnetorheological elastomer shock absorber 3 and the response acceleration signal under different currents such as Figure 3 As shown, these data cover the results from low frequency to high frequency (sweeping up), followed by the results from high frequency to low frequency (sweeping down).

[0075] Furthermore, based on the single-degree-of-freedom magnetorheological elastomer shock absorber-load mass system, a device frequency-dependent stiffness and damping identification model is established. This model can obtain the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber through only simple time-frequency conversion and a series of real and imaginary part analyses.

[0076] Finally, through the frequency-dependent stiffness and damping identification module, based on the frequency-dependent stiffness and damping model and the preprocessed test signal, the dynamic stiffness and damping under wide-band and continuous frequency can be identified.

[0077] This embodiment also provides a frequency-variant stiffness and damping identification method for a magnetorheological elastomer vibration absorber, which is used to implement a frequency-variant stiffness and damping model construction module and a frequency-variant stiffness and damping identification module of a frequency-variant stiffness and damping identification system for a magnetorheological elastomer vibration absorber.

[0078] The model takes the preprocessed swept frequency excitation and response and velocity signal as input, and the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber as output, such as Figure 1 As shown in the right block diagram, the steps are as follows:

[0079] S1, import Figure 3 The pre-processed sweep vibration excitation and response and velocity signal are recorded as and Calculate the frequency-dependent function of the excitation-response ratio by Fast Fourier Transform (FFT) analysis

[0080] S2, based on Obtain the frequency-dependent complex function Trr(jω) and calculate its real part Re{Trr(jω)}, imaginary part Im{Trr(jω)} and modulus square |Trr(jω)| 2 .

[0081] S3, respectively according to and The frequency-dependent stiffness k(ω) and damping c(ω) of the magnetorheological elastomer shock absorber are calculated and output.

[0082] The key parameters and function derivation process in the above steps are as follows:

[0083] The motion equation of the magnetorheological elastomer damper-load mass single degree of freedom system is:

[0084]

[0085] Where m is the load mass, ω is the vibration angular frequency, and x is e With x r are the excitation and response displacement signals, respectively; k(ω) and c(ω) are the frequency-dependent stiffness and damping coefficient of the device, respectively.

[0086] Through Laplace transform, equation (1) can be written as:

[0087] X r (s)(ms 2 +c(ω)s+k(ω))=X e (s)(c(ω)s+k(ω)) (2)

[0088] Then the transfer function of system excitation to response displacement (i.e. the inverse of vibration displacement transmissibility) is:

[0089]

[0090] Similarly, the transfer function of system excitation to response acceleration is:

[0091]

[0092] Substituting s = jω into equation (4), we obtain

[0093]

[0094] set up Then formula (5) is expressed as:

[0095]

[0096] The real and imaginary parts of the frequency-dependent complex function Trr(jω) are:

[0097]

[0098]

[0099] From equations (6)-(8), the frequency-dependent stiffness and damping of the device can be obtained as follows:

[0100]

[0101]

[0102] Among them, the real part, imaginary part and modulus square of Trr(jω) can be further obtained by equations (11)-(13):

[0103]

[0104]

[0105]

[0106] In the above formulas (11) to (13), Both ω and ω can be obtained by processing the data of the swept frequency vibration test results. Then, they are substituted into equations (9) and (10) to obtain the frequency-dependent stiffness and damping coefficient of the magnetorheological elastomer shock absorber.

[0107] In particular, A frequency-dependent function that represents the ratio of excitation to response, which is different from the frequency response function in traditional transfer characteristic tests.

[0108] The identification results of this embodiment are as follows Figure 4 As shown, Figure 4 (a) is the model The real and imaginary results of , the real and imaginary parts of Trr(jω) and the squared modulus; Figure 4 (b) is a diagram showing the frequency-dependent stiffness and damping effect of the magnetorheological elastomer shock absorber under different currents in this embodiment. Several key information of the device can be obtained from the model identification results:

[0109] ① Variation trend of device dynamic stiffness and damping with continuous frequency under different currents.

[0110] In this embodiment, the frequency range of the sweep test is 50-180 Hz. As the frequency increases continuously, the stiffness of the magnetorheological elastomer shock absorber shows an overall increasing trend, and the damping shows an overall decreasing trend. Figure 5 As shown in the figure on the left, this result is used to describe the frequency-dependent mechanism of the device and assist in the response analysis, dynamic modeling and intelligent control of the magnetorheological elastomer vibration reduction system.

[0111] ② The influence of different currents on the dynamic stiffness and damping of the device under continuous frequency.

[0112] In this embodiment, at almost all frequencies, the increase in current will lead to an increase in the dynamic stiffness and damping of the magnetorheological elastomer shock absorber, such as Figure 5 As shown by the arrow in the middle, this phenomenon clearly reflects the magnetorheological effect of the magnetorheological elastomer material. This result is used to describe the magnetic control mechanism of the device and assist the control simulation and experiment of the magnetorheological elastomer vibration reduction system.

[0113] ③ Resonance information of magnetorheological elastomer vibration reduction system under different currents.

[0114] The resonance information of the MR elastomer vibration damping system can also be extracted from the frequency-dependent stiffness and damping curves. One corresponds to the trough of the frequency-dependent stiffness curve, and the other corresponds to the inflection point of the frequency-dependent damping curve. Figure 5 The resonance information of this embodiment is intuitively represented by points of different shapes. The horizontal axis represents the resonance frequency, and the vertical axis represents the dynamic stiffness and damping at the frequency. The relative error between the identification result and the equivalent stiffness and equivalent damping calculated by the traditional transmissibility curve based on the resonance peak information is less than 3%. The specific values ​​and comparison information are as follows: Figure 6 As shown in Table 1. The present invention can not only effectively characterize the frequency-related stiffness and damping of the magnetorheological elastomer shock absorber, but also accurately identify its resonance information.

[0115] Table 1 System resonance information obtained by the method of the present invention

[0116]

[0117]

[0118] The present invention can identify the frequency-dependent stiffness and damping characteristics of the device within a wide frequency range through a single test. It theoretically analyzes the magnetorheological elastomer shock absorber-load mass system model, performs a series of real and imaginary part analysis and transformation on the inverse of the vibration transfer function, establishes a frequency-dependent stiffness and damping model of the magnetorheological elastomer shock absorber, and then measures the device excitation and response acceleration signals based on a simple and universal sweep frequency vibration test system for the shock absorber. The test results can be used to identify the dynamic stiffness and damping under wide and continuous frequencies.

[0119] The present invention proposes a method and system for identifying the frequency-dependent stiffness and damping of a magnetorheological elastomer shock absorber. Based on a simple and universal swept-frequency vibration test of the shock absorber, the frequency-dependent stiffness and damping characteristics of the device within a wide frequency range can be identified with only a single test without the need for additional tooling design, and additional system resonance information. In addition, the present invention is universal and general. As long as the actuator can be used for swept-frequency vibration testing, the system and method proposed by the present invention can be used to identify its frequency-dependent stiffness and damping characteristics, not limited to the frequency-dependent stiffness and damping identification of magnetorheological elastomer shock absorbers.

[0120] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A frequency-dependent stiffness and damping identification system for a magnetorheological elastomer shock absorber, characterized in that: include: The sweep frequency vibration test module of the magnetorheological elastomer vibration damping device is used to perform sweep frequency test on the device and collect and record the original data; A test signal preprocessing module is used to receive raw data and perform signal filtering and noise reduction processing; Frequency-dependent stiffness and damping model building module, used to build the frequency-dependent stiffness and damping identification model of magnetorheological elastomer shock absorber; The frequency-dependent stiffness and damping identification module identifies and outputs the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber based on the test signal data and identification model.

2. The frequency-dependent stiffness and damping identification system of the magnetorheological elastomer shock absorber according to claim 1, characterized in that: The magnetorheological elastomer vibration damping device sweep frequency vibration test module comprises: a magnetorheological elastomer vibration damper, a load mass block, an electromagnetic vibration table, a first acceleration sensor, a data acquisition instrument, a computer, a controller, a power amplifier, a second acceleration sensor and a DC power supply; Wherein, the second acceleration sensor and the magnetorheological elastomer shock absorber are both arranged above the electromagnetic vibration table; the load mass block is arranged above the magnetorheological elastomer shock absorber; the first acceleration sensor is arranged above the load mass block; the controller, the power amplifier, the data acquisition instrument, the computer and the DC power supply are respectively arranged at intervals on one side of the electromagnetic vibration table; The electromagnetic vibration table, the controller, the power amplifier and the computer are connected in sequence by wires; the DC power supply is connected by wires to the magnetorheological elastomer shock absorber; and the first acceleration sensor and the second acceleration sensor are both connected by wires to the data acquisition instrument.

3. The frequency-dependent stiffness and damping identification system of the magnetorheological elastomer shock absorber according to claim 2, characterized in that: The first acceleration sensor is used to collect a response acceleration signal, and the second acceleration sensor is used to collect an excitation acceleration signal. The response acceleration signal and the excitation acceleration signal are synchronously recorded by the data acquisition instrument.

4. The frequency-dependent stiffness and damping identification system of a magnetorheological elastomer shock absorber according to claim 1, characterized in that: In the test signal preprocessing module, a bandpass filter is used to eliminate high-frequency and low-frequency noises in the original data.

5. The frequency-dependent stiffness and damping identification system of the magnetorheological elastomer shock absorber according to claim 1, characterized in that: In the frequency-variant stiffness and damping model construction module, a device frequency-variant stiffness and damping identification model is established based on a single-degree-of-freedom magnetorheological elastomer shock absorber-load mass system, and the frequency-dependent stiffness and damping of the magnetorheological elastomer shock absorber are obtained through time-frequency conversion and real and imaginary part analysis.

6. The frequency-dependent stiffness and damping identification system of the magnetorheological elastomer vibration absorber according to claim 1, characterized in that: The frequency-dependent stiffness and damping identification module identifies the dynamic stiffness and damping under broadband and continuous frequency based on the frequency-dependent stiffness and damping model and the preprocessed test signal.

7. A method for identifying frequency-dependent stiffness and damping of a magnetorheological elastomer shock absorber, characterized in that: A frequency-dependent stiffness and damping identification system applied to a magnetorheological elastomer shock absorber, the method comprising: S1, import the pre-processed sweep vibration excitation and response and velocity signal, respectively recorded as and Calculate the frequency-dependent function of the excitation-response ratio by Fast Fourier Transform (FFT) analysis S2, based on Obtain the frequency-dependent complex function Trr(jω) and calculate its real part Re{Trr(jω)}, imaginary part Im{Trr(jω)} and modulus square |Trr(jω) 2 ; S3, respectively according to and The frequency-dependent stiffness k(ω) and damping c(ω) of the magnetorheological elastomer shock absorber are calculated and output.

8. The method for identifying frequency-dependent stiffness and damping of a magnetorheological elastomer shock absorber according to claim 7, characterized in that: The derivation process is as follows: The motion equation of the magnetorheological elastomer damper-load mass single degree of freedom system is: Where m is the load mass, ω is the vibration angular frequency, and x is e With x r are the excitation and response displacement signals, respectively, k(ω) and c(ω) are the frequency-dependent stiffness and damping coefficient of the device, respectively; Through Laplace transform, equation (1) can be written as: X r (s)(ms 2 +c(ω)s+k(ω))=X e (s)(c(ω)s+k(ω)) (2) Then the transfer function of system excitation to response displacement (i.e. the inverse of vibration displacement transmissibility) is: Similarly, the transfer function of system excitation to response acceleration is: Substituting s = jω into equation (4), we obtain set up Then formula (5) is expressed as: The real and imaginary parts of the frequency-dependent complex function Trr(jω) are: From equations (6)-(8), the frequency-dependent stiffness and damping of the device can be obtained as follows: Among them, the real part, imaginary part and modulus square of Trr(jω) can be further obtained by equations (11)-(13): In the above formulas (11) to (13), Both ω and ω can be obtained by processing the data of the swept frequency vibration test results. Then, they are substituted into equations (9) and (10) to obtain the frequency-dependent stiffness and damping coefficient of the magnetorheological elastomer shock absorber.

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