CN111879400B - System and method for measuring module modal parameters of spacecraft electromechanical product - Google Patents

Abstract

The invention relates to a system and a method for measuring modal parameters of a component of an electromechanical product of a spacecraft, wherein the component is a high-speed rotor of a gyroscope, a high-speed rotor of a control moment gyroscope or a rotor of a flywheel, and the modal parameters comprise frequency, vibration mode and damping, and the system and the method belong to the technical field of modal measurement of small-mass mechanical components. The MEMS accelerometer is used for modal measurement of small-mass components such as a gyro high-speed rotor, so that the influence of the weight of the sensor on the mass distribution of the measured rotor is reduced, and the rotor modal measurement precision is improved. The oscilloscope is used for replacing a pre-set and analysis software of the traditional accelerometer, and modal frequency, modal vibration mode and modal damping are obtained by simple operation, so that modal measurement cost is greatly reduced. The method can be applied to the accurate measurement of the modal parameters of the components such as the rotor of the control moment gyroscope, the flywheel, the two-floating gyroscope, the three-floating gyroscope and other products. The invention can also be applied to the modal measurement of the high-speed motor rotor, and has wide market prospect.

Description

A system and method for measuring modal parameters of components of spacecraft electromechanical products

technical field

The invention relates to a component modal parameter measurement system and method for aerospace mechanical and electrical products. The component is a high-speed rotor of a gyro, a high-speed rotor of a control torque gyro or a rotor of a flywheel. The technical field of modal measurement of quality mechanical components.

Background technique

High-speed rotors are the core components of spacecraft inertial actuators, three-floating gyroscopes, and two-floating gyroscopes. Its modal design affects the stability and operation accuracy of the whole machine, and the measurement of modal characteristics (frequency, mode shape and damping) is an important means to verify the accuracy of modal design and carry out design iteration.

The modal of the rotor structure is an important design element, and the modal analysis of the components is one of the foundations and cores of the modal analysis of the whole machine. The accuracy of the modal parameters of the components directly affects the accuracy of the modal analysis of the whole machine. The modal measurement and implementation of small-mass components are more difficult.

CMG, gyroscope, etc. are assembled by multiple components. The connection modeling error of multiple components, component processing and assembly errors will bring difficulties to the high-precision finite element analysis of the modal of the whole machine. In most cases, Simple finite element analysis only has a qualitative effect on the acquisition of modal parameters, which requires accurate testing of modal parameters. The measured modal parameters can provide feedback to the design analysis to modify the finite element analysis model.

The mechanical vibration test is mainly realized by the contact accelerometer, and the test sensor is fixed on the DUT. Currently available vibration sensors are generally piezoelectric or charge-type, with a weight of more than 10 grams. The mass of the sensor itself will change the structure of the tested object, which has a great impact on the test accuracy. In addition, such high-precision vibration sensors require external charge amplifiers and high-speed data collectors, which are extremely costly and complicated to implement.

There is an urgent need to realize a high-precision component modal parameter measurement method that has little influence on the mass distribution of the component under test (especially for small-mass components), and has high detection accuracy, light weight, high range and easy implementation.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, and to provide a component modal parameter measurement system and method of a spacecraft electromechanical product.

The technical solution of the present invention is:

A component modal parameter measurement system of a spacecraft electromechanical product, the measurement system comprising a vibration detection module, a signal processing module, a modal mode shape analysis module and a modal damping analysis module;

The vibration detection module is a PCB-type micro vibration measurement module based on an acceleration chip, including an acceleration chip, a filter module and a PCB board. The acceleration chip and the filter module are fixed on the PCB board. A MEMS acceleration chip with a wide range, taking a CMG rotor as an example, the vibration detection module is fixed on the measured rotor by means of adhesion, and the sticking positions are the bearing support points (two) and the rotor modal vibration shape determined by Ansys pre-analysis The node, maximum point, etc., are fixed with cotton thread (or soft thin thread) to fix the CMG rotor, and the fixed point is the node of the modal vibration shape of the rotor;

When the end of the CMG rotor (at the maximum point of the mode shape) is struck with a modal hammer, the acceleration chip in the vibration detection module located at the sticking point is sensitive to the vibration and converts the vibration into a voltage signal and outputs it to the filter module. Filter the received voltage signal and output the filtered voltage signal to the signal processing module;

The signal processing module is used to receive the filtered voltage signal output by the vibration detection module, and perform FFT analysis on the received filtered voltage signal to obtain the peak frequency and corresponding amplitude of the filtered voltage signal, and will obtain The peak frequency and corresponding amplitude of the filtered voltage signal are output to the modal mode shape analysis module and the modal damping analysis module;

The modal shape analysis module is used to receive the filtered voltage signal peak frequency and corresponding amplitude sent by the signal processing module, and to plot and sum the received peak frequencies of different sticking points at the same time. Cubic spline interpolation calculation to obtain the rotor mode shape;

The modal damping analysis module is used for receiving the filtered peak frequency and corresponding amplitude of the voltage signal sent by the signal processing module, and performing analysis and calculation according to the amplitude change of the received peak frequency of the same sticking point at different times, get the rotor modal damping;

The filtering module is realized by RC filtering, the filtering bandwidth is 5-10 times of the measured peak frequency, and the acceleration chip senses the vibration force of the tested piece and converts it into a vibration electrical signal;

The signal processing module, taking the four-channel oscilloscope as an example, takes the voltage signal U1 output by the vibration detection module pasted at the bearing support point as the reference signal and connects to the oscilloscope channel 1, and performs FFT transformation on the voltage signal U1 to obtain the model of the rotor. The amplitude of the modal frequency F1 is recorded as M11, and the voltage signal U2 output by the vibration detection module pasted at the position of another bearing support point is used as the reference signal to connect to the oscilloscope channel 2, and the vibration detection is pasted at the node position of the rotor modal mode shape. The voltage signal U3 output by the module is connected to the oscilloscope channel 3 as the reference signal, and the voltage signal U4 output by the vibration detection module pasted at the maximum point position of the rotor modal mode shape is connected to the oscilloscope channel 4 as the reference signal, and the voltage signal U2 is connected to the oscilloscope channel 4. , the voltage signal U3 and the voltage signal U4 are respectively subjected to FFT transformation to obtain the amplitude of the modal frequency F1 of the rotor and denote it as M12, the amplitude of the modal frequency F1 of the rotor and denote it as M13, and the modal frequency of the rotor F1. The amplitude is recorded as M14, and then in the time domain, the voltage signal U2 input by oscilloscope channel 2, the voltage signal U3 input by oscilloscope channel 3, and the voltage signal U4 input by oscilloscope channel 4 and the voltage signal U1 input by oscilloscope channel 1 are respectively in the time domain. The phases on the scale of frequency F1 are compared, if they are in phase, no processing is performed, and if they are out of phase, a negative sign is added before the amplitude of the corresponding modal frequency;

Using the above steps, the amplitude of each measuring point of the modal frequency F2, F3... can be measured;

If there are remaining measuring points, follow the above steps to test until the measurement is completed, and get M15, M16...;

The modal shape analysis module firstly normalizes the vibration amplitude of each test point corresponding to the test modal frequency obtained by the signal processing module, and normalizes the amplitude M11 reference to 1 to obtain an amplitude sequence [1, M12', M13', ...], use the cubic spline interpolation function to fit the amplitude sequence [1, M12', M12', ...], that is, the normalized amplitude of the amplitude M11 is 1, and the normalized amplitude of the amplitude M12 is 1. The normalized amplitude is M12', and so on;

The strain hysteresis stress of the rotor material itself will form the material internal resistance, which needs to be tested. The modal damping analysis module adopts the time domain method to test the rotor vibration attenuation speed to obtain the damping of the corresponding vibration mode, in order to eliminate the disturbance of the hammering action process. , the timing starts from a period of time (>5ms) after the vibration starts, and the relationship between the modal amplitude and time is:

Among them, F1 is the rotor modal frequency, ξ is the corresponding modal damping, and A(t) is the U(t) of the amplitude at time t under the F1 modal frequency.

In the same way, the modal damping of the response at the modal frequencies F2, F3... can be obtained.

A method for measuring modal parameters of components of a spacecraft electromechanical product, the steps of the method include:

(1) Ansys pre-analysis determines the nodes and maximum points of the rotor mode shape. The vibration detection module is pasted on the bearing support point and the node and maximum point of the modal mode shape of the rotor, and the rotor is suspended and fixed with cotton threads (or soft thin wires). point;

(2) Hit the end of the CMG rotor (at the maximum point of the mode shape) with a modal hammer, and the vibration detection modules located at different sticking points filter the voltage signal converted by the rotor response and send it to the signal processing module at the same time; there are two kinds of Type data, one group is the response signals of different sticking points at the same time; one group is the response signals that change with time after each sticking point is hammered;

(3) The signal processing module performs FFT analysis on the filtered voltage signal output by the received vibration detection module to obtain the peak frequency and corresponding amplitude of the filtered voltage signal, and compares the obtained filtered voltage signal peak frequency and The corresponding amplitude is output to the modal mode shape analysis module and the modal damping analysis module;

(4) The mode shape analysis module performs point tracing and cubic spline interpolation calculation according to the peak frequency of the voltage signal output by the signal processing module, the corresponding amplitude and the received amplitude of the peak frequency of different sticking points at the same time. The modal shape of the rotor;

(5) The modal damping analysis module analyzes and calculates according to the peak frequency of the voltage signal output by the signal processing module, the corresponding amplitude and the amplitude change of the received peak frequency of the same sticking point at different times, and obtains the rotor modulus by the following formula state damping;

Among them, F1 is the rotor modal frequency, ξ is the corresponding modal damping, and A(t) is the U(t) of the amplitude at time t under the F1 modal frequency.

In the same way, the modal damping of the response at the modal frequencies F2, F3... can be obtained.

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

(1) The PCB type vibration sensor of the present invention is a miniature, light-weight, wide-range and high-precision mems vibration sensor.

(2) The PCB-type vibration sensor of the present invention has a small mass, has little influence on the mass distribution of the component under test (especially for small-mass components), and has high detection accuracy.

(3) The present invention can obtain the modal frequency, mode shape, damping and other parameters of the measured structure, and can realize the accurate measurement of the modal of the measured body.

(4) The present invention uses an oscilloscope to replace the traditional accelerometer's front end device and analysis software, and uses simple numerical calculation to achieve modal frequency, modal mode shape and modal damping, which is simple to implement and greatly reduces modal measurement costs.

(5) A method for measuring the modal parameters of miniature high-precision components, which uses MEMS accelerometers to measure the modal parameters of small-mass components such as gyro high-speed rotors, reduces the influence of the sensor weight on the mass distribution of the measured rotor, and improves the modal measurement accuracy of the rotor. . The oscilloscope is used to replace the traditional accelerometer's preprocessor and analysis software, and the modal frequency, modal mode shape and modal damping can be obtained by simple operation, which greatly reduces the modal measurement cost. It can be used to accurately measure the modal parameters of components such as rotors of products such as control moment gyroscopes, flywheels, two-floating gyroscopes, and three-floating gyroscopes. The invention can also be applied to the modal measurement of the rotor of the high-speed motor, and has a broad market prospect.

Description of drawings

Fig. 1 is the schematic diagram of bonding of vibration detection module of the present invention;

Fig. 2 is the structural block diagram of the vibration detection module of the present invention;

3 is a schematic diagram of a signal processing module of the present invention;

4 is a schematic diagram of a modal mode shape analysis module of the present invention;

FIG. 5 is a schematic diagram of a modal damping analysis module of the present invention.

Detailed ways

As shown in FIG. 1, it is a structural block diagram of the present invention, including a vibration detection module, a signal processing module, a modal mode shape analysis module, and a modal damping analysis module. The vibration detection module is a PCB-type micro vibration measurement module based on an acceleration chip. Including acceleration chip, filter module, mounted on PCB. The acceleration chip selects a MEMS acceleration chip with small volume and weight, high bandwidth and wide range). Taking the CMG rotor as an example, the vibration detection module is fixed on the tested rotor by adhesion, and the sticking position is the bearing support point and the node and maximum point of the modal vibration shape determined by Ansys pre-analysis. Tap the end of the rotor (at the point of maximum mode shape). The vibration detection module obtains the rotor vibration signal at the sticking point and transmits it to the general oscilloscope. The oscilloscope performs FFT analysis on the vibration signal measured by the vibration detection module to obtain the peak frequency and corresponding amplitude of the vibration signal, which are sent to the modal mode shape analysis module and In the modal damping analysis module, the modal vibration analysis module performs point plotting and cubic spline interpolation calculations based on the amplitudes of the peak frequencies of different test points obtained by the signal processing module at the same time, and obtains the rotor modal vibration shape. The modal damping analysis module performs analysis and calculation according to the amplitude changes of the peak frequencies of the same test point obtained by the signal processing module at different times, and obtains the rotor modal damping.

As shown in FIG. 2 , it is a structural block diagram of the vibration detection module of the present invention, including an acceleration chip and a filter module, which are installed on the PCB. The acceleration chip selects a MEMS acceleration chip with small volume and weight, high bandwidth and wide range. Its filtering module is realized by RC filtering, and the filtering bandwidth is 5-10 times of the measured modal frequency. The acceleration chip senses the vibration force of the DUT, converts it into a vibration electrical signal, and sends it to the oscilloscope module.

As shown in Figure 3, it is a schematic diagram of the signal processing module of the present invention. Taking a four-channel oscilloscope as an example, the vibration signal at one end of the measuring point is selected as the reference signal to connect to the oscilloscope channel 1, and the signal is subjected to FFT transformation to obtain the measured mode. The amplitude of frequency F1 is also recorded as M11. Connect the measuring point 2-4 to the oscilloscope channel 2-4, perform FFT transformation on each signal one by one, and obtain the amplitude of the measured modal frequency, which is recorded as M12-M14. And compare the phase of the channel 2-4 signal and the channel 1 signal on the frequency F1 scale in the time domain. If inverted, add a minus sign before the magnitude of the corresponding modal frequency. If there are remaining measuring points, follow the above steps to test until the measurement is completed, and get M15, M16... . The amplitude of each measuring point of modal frequency F2, F3... can be measured by the above steps.

As shown in FIG. 4 , it is a schematic diagram of the modal mode shape analysis module of the present invention. First, normalize the vibration amplitude of each test point corresponding to the test modal frequency obtained by the signal processing module, and normalize it to 1 with the reference signal as a reference, and obtain the amplitude sequence [1, M11', M12',...] , [1, M21', M22', ...], ....

Then, use the cubic spline interpolation function to fit the amplitude sequence [1, M11', M12', ...], and compare the rotor mode shape with the original data after fitting.

As shown in FIG. 5 , it is a schematic diagram of the modal damping analysis module of the present invention. The strain hysteresis stress of the rotor material itself will form the internal resistance of the material, which needs to be tested. Here, the time domain method is used to test the vibration attenuation speed of the rotor to obtain the damping of the corresponding vibration mode. In order to eliminate the disturbance of the hammering action process, the timing was started 10mS after the vibration started.

The modal amplitude changes with time as:

Among them, F1 is the rotor modal frequency, ξ is the corresponding modal damping, and A(t) is the U(t) of the amplitude at time t under the F1 modal frequency.

The amplitude of the first-order modal F1 of the rotor is 11.3dB higher at the moment of 110mS than that at the moment of 10mS. The following formula is derived from formula (1):

Solved to get ξ=0.004776.

Example

Taking the CMG rotor as an example, the nodes and maximum points of the rotor modal vibration shape are firstly determined through Ansys pre-analysis; The node of the type, the maximum point. Use cotton thread (or soft thin thread) to suspend and fix the rotor. One end of the fixed point is the node of the rotor's mode shape, and the other end is the suspension point.

Hit the end of the CMG rotor (at the maximum point of the mode shape) with a modal hammer, the vibration detection module at bearing support point 1 outputs U1(t), and the vibration detection modules at other sticking points output U2(t), U3(t) ) and U4(t). Send U1(t), U2(t), U3(t) and U4(t) to the signal processing module at the same time. Use the voltage signal U1(t) output by the vibration detection module pasted at the bearing support point 1 as the reference signal to connect to the oscilloscope channel 1, and U2(t), U3(t) and U4(t) to connect to the oscilloscope 2, 3, 4 aisle.

The signal processing module performs FFT analysis on the received U1(t), U2(t), U3(t) and U4(t) output by the vibration detection module, and obtains the peak frequency and corresponding amplitude of the filtered voltage signal. U1(t) FFT analysis finds the frequency with the highest amplitude to obtain the modal frequency of the rotor 702Hz; the amplitude is recorded as M11=1.2V; for U2(t) FFT analysis, the amplitude is obtained and recorded as M12=1.2V; for U3 (t) The amplitude of the FFT analysis is obtained and recorded as M13=0.1V; the amplitude of the rotor is obtained by the FFT analysis of U4 and recorded as M14=1.4V; then the voltage signal U2 input to the oscilloscope channel 2 in the time domain , The voltage signal U3 input by oscilloscope channel 3 and the voltage signal U4 input by oscilloscope channel 4 are compared with the phase of the voltage signal U1 input by oscilloscope channel 1 on the frequency scale of 702Hz. Add a minus sign before the magnitude of the corresponding modal frequency.

The obtained peak frequency and corresponding amplitude of the filtered voltage signal are output to the modal mode shape analysis module and modal damping analysis module; the modal mode shape analysis module is based on the voltage signals U1(t) and U2 output by the signal processing module. (t), U3(t) and U4(t), peak frequency 702Hz, and corresponding amplitudes M11=1.2V, M12=1.2V, M13=0.1V, M14=1.4V to perform point tracing and cubic spline interpolation calculations, first Normalize the vibration amplitude of each test point corresponding to the test modal frequency obtained by the signal processing module, normalize the amplitude M11 reference to 1, and obtain the amplitude sequence [1, 1, 0.1/1.2, 1.4/1.2] , that is, the normalized amplitude of the amplitude M11 is 1, the normalized amplitude of the amplitude M12 is 1, and so on, to obtain the rotor modal shape.

The modal damping analysis module obtains the rotor modal damping by the following formula according to the peak frequency and corresponding amplitude of the voltage signal output by the signal processing module, and the amplitude change of the received peak frequency at the same sticking point at different times; The time-varying relationship is:

The rotor's first-order mode F1=702Hz amplitude is 11.3dB higher at 110mS time than 10mS time. The following formula is derived from formula (1):

Solved to get ξ=0.004776.

The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims (8)

1. A component modal parameter measurement system of spacecraft electromechanical products is characterized in that: the measuring system comprises a vibration detection module, a signal processing module, a modal shape analysis module and a modal damping analysis module;

the vibration detection module comprises an acceleration chip, a filtering module and a PCB (printed circuit board), wherein the acceleration chip and the filtering module are fixed on the PCB, the vibration detection module is fixed on a tested rotor in an adhesion mode, the adhesion positions are a bearing supporting point, a node of a rotor modal vibration mode and a maximum point of the rotor modal vibration mode, the rotor is in a suspension mode, and a fixed point during suspension is the node of the rotor modal vibration mode;

the vibration detection module is also used for sensing vibration, converting the vibration into a voltage signal and outputting the voltage signal to the filtering module;

the filtering module is used for filtering the received voltage signal and outputting the filtered voltage signal to the signal processing module;

the signal processing module is used for receiving the filtered voltage signal output by the vibration detection module, performing FFT analysis on the received filtered voltage signal to obtain a filtered voltage signal peak frequency and a corresponding amplitude, and outputting the obtained filtered voltage signal peak frequency and the obtained filtered voltage signal corresponding amplitude to the modal vibration type analysis module and the modal damping analysis module;

the modal shape analysis module is used for receiving the filtered voltage signal peak frequency and the corresponding amplitude sent by the signal processing module, and performing point tracing and cubic spline interpolation calculation according to the received amplitudes of the peak frequencies of different pasting points at the same moment to obtain the rotor modal shape;

the modal damping analysis module is used for receiving the filtered voltage signal peak frequency and the corresponding amplitude sent by the signal processing module, and carrying out analysis operation according to the received amplitude change of the peak frequency of the same pasting point at different moments to obtain rotor modal damping;

the signal processing module is a four-channel oscilloscope, a voltage signal U1 output by a vibration detection module pasted at a bearing supporting point position is taken as a reference signal to be connected into an oscilloscope channel 1, FFT conversion is carried out on the voltage signal U1 to obtain the amplitude of the modal frequency F1 of the rotor and is recorded as M11, a voltage signal U2 output by a vibration detection module pasted at another bearing supporting point position is taken as a reference signal to be connected into an oscilloscope channel 2, a voltage signal U3 output by a vibration detection module pasted at a node position of the modal shape of the rotor is taken as a reference signal to be connected into an oscilloscope channel 3, a voltage signal U4 output by a vibration detection module pasted at the maximum value position of the modal shape of the rotor is taken as a reference signal to be connected into an oscilloscope channel 4, and FFT conversion is respectively carried out on the voltage signal U2, the voltage signal U3 and the voltage signal U4 to obtain the amplitude of the modal frequency F1 of the rotor and is recorded as M12, The amplitude of the modal frequency F1 of the rotor is recorded as M13, and the amplitude of the modal frequency F1 of the rotor is recorded as M14, then the phase of the voltage signal U2 input by the oscilloscope channel 2, the phase of the voltage signal U3 input by the oscilloscope channel 3 and the phase of the voltage signal U4 input by the oscilloscope channel 4 on the frequency F1 scale are respectively compared with the phase of the voltage signal U1 input by the oscilloscope channel 1 on the time domain, if the phases are the same, no processing is carried out, and if the phases are reversed, a negative sign is added before the amplitude of the corresponding modal frequency;

the interpolation calculation method comprises the following steps: the modal shape analysis module firstly normalizes the vibration amplitude of the test modal frequency corresponding to each test point obtained by the signal processing module, normalizes the amplitude M11 to 1 to obtain an amplitude sequence [1, M12 ', M13 ', … … ], and fits the amplitude sequence [1, M12 ', M13 ', … … ] by a cubic spline interpolation function, namely the normalized amplitude of the amplitude M11 is 1, the normalized amplitude of the amplitude M12 is M12 ', and the like.

2. The system according to claim 1, wherein the system comprises: the vibration detection module is a PCB type micro-vibration measurement module based on an acceleration chip, nodes and maximum points of the rotor modal vibration mode are determined by Ansys pre-analysis, and the rotor is suspended and fixed by cotton wires or soft thin wires.

3. The system according to claim 1, wherein the system comprises: an acceleration chip in the vibration detection module at the attachment point is used to sense vibrations when the CMG rotor end is struck with a modal hammer.

4. The system according to claim 1, wherein the system comprises: the filtering module is realized by RC filtering, and the filtering bandwidth is 5-10 times of the measured peak frequency.

5. The system according to claim 1, wherein the system comprises: the analysis operation refers to: the modal damping analysis module tests the vibration attenuation speed of the rotor by adopting a time domain method to obtain the damping of a corresponding vibration mode, timing is started after 5s from the beginning of vibration, and the change relation of modal amplitude along with time is as follows:

where F1 is the rotor modal frequency, ξ is the corresponding modal damping, and A (t) is U (t) at time t in amplitude at the F1 modal frequency.

6. A method for measuring the module modal parameters of spacecraft electromechanical products is characterized in that: with the measuring system of claim 1, the steps of the method comprising:

(1) firstly, determining a node and a maximum point of a rotor modal shape, then pasting a vibration detection module on a bearing supporting point, the node and the maximum point of the rotor modal shape, and suspending a rotor;

(2) knocking the end part of the CMG rotor by using a modal hammer, filtering voltage signals converted by rotor response by vibration detection modules positioned at different sticking points, and simultaneously sending the voltage signals to a signal processing module;

(3) the signal processing module performs FFT analysis on the received filtered voltage signal output by the vibration detection module to obtain a filtered voltage signal peak frequency and a corresponding amplitude, and outputs the filtered voltage signal peak frequency and the corresponding amplitude to the modal vibration type analysis module and the modal damping analysis module;

(4) the modal shape analysis module performs point tracing and cubic spline interpolation calculation according to the peak frequency of the voltage signal output by the signal processing module, the corresponding amplitude and the amplitude of the peak frequency of the received different pasting points at the same moment to obtain the rotor modal shape;

(5) the modal damping analysis module performs analysis operation according to the peak frequency and the corresponding amplitude of the voltage signal output by the signal processing module and the received amplitude change of the peak frequency of the same pasting point at different moments, and obtains rotor modal damping through the following formula;

where F1 is the rotor modal frequency, ξ is the corresponding modal damping, and A (t) is U (t) at time t in amplitude at the F1 modal frequency.

7. The method for measuring the modal parameters of the components of the electromechanical product of a spacecraft according to claim 6, wherein: in the step (2), the data sent to the signal processing module includes response signals of different pasting points at the same time and response signals of each pasting point changing with time after being hammered.

8. The method for measuring the component modal parameters of the spacecraft electromechanical product according to claim 6, wherein the method comprises the following steps: when the rotor is suspended, the rotor is suspended and fixed by using cotton threads or soft thin threads, the fixed point at one end is a node of the rotor modal vibration mode, and the other end is a suspension point.

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