1. A ground vibration noise common mode rejection method based on a vibration sensor is characterized by comprising the following steps:

fixedly connecting a micro-thrust measuring system and a vibration sensor to the same platform;

the platform is driven to move by piezoelectric drivers arranged at different positions on the platform, and a single sensitive axis of the micro-thrust measuring system is matched with a coordinate axis of the vibration sensor by comparing output results of the micro-thrust measuring system and the vibration sensor;

a driving signal with characteristic frequency f is externally generated and transmitted to a piezoelectric driver, the piezoelectric driver drives the platform to move in the direction of a single sensitive axis of the micro-thrust measuring system, and the outputs of the micro-thrust measuring system and the vibration sensor are respectively recorded; and simultaneously, externally generating unit orthogonal demodulation signals with the same frequency and phase as the driving signals, demodulating the demodulation signals with the outputs of the micro-thrust measuring system and the vibration sensor respectively, extracting amplitude ratio and phase difference information of output results of the micro-thrust measuring system and the vibration sensor, fitting to obtain a high-precision correction transfer function after accumulating comparison information of enough frequency points, synchronizing the outputs of the micro-thrust measuring system and the vibration sensor, and further deducting vibration noise through a common mode.

2. The ground vibration noise common mode rejection method according to claim 1, wherein the step of matching a single sensitive axis of said micro thrust measurement system with a coordinate axis of said vibration sensor comprises: the platform is driven to move by a piezoelectric driver, the gravity acceleration component is used for calibration, the output of the micro-thrust measurement system is decomposed to the coordinate axis of the vibration sensor, the correlation in each axial direction is analyzed, and the coefficient of the micro-thrust measurement system in each direction is determined; the expression formula is as follows:

F_out＝K_iF_I+K_oF_O+K_pF_P

in the formula, F_I、F_O、F_PIndicating the output of three coordinate axes of the vibration sensor by adjusting K_i、K_o、K_pAnd the micro-thrust measurement system is matched with the coordinate axis of the vibration sensor according to the coefficient in the coordinate axis direction.

3. The ground vibration noise common mode rejection method according to claim 1, wherein in the process of matching said micro thrust measurement system with said vibration sensor, further comprising the steps of: and rotating and finely adjusting the micro-thrust measuring system and the vibration sensor to ensure that a sensitive shaft of the micro-thrust measuring system and a shaft of the vibration sensor are respectively consistent with the motion direction of the platform.

4. The ground vibration noise common mode rejection method according to claim 3, wherein the step of rotationally fine-tuning said micro thrust measurement system and vibration sensor comprises: and when the driving signals are applied to the platform in different directions, the micro-thrust testing system and the vibration sensor are rotated and finely adjusted respectively, so that the output values of the micro-thrust testing system and the vibration sensor in the same input signal direction are maximum, and the output value in the orthogonal direction is minimum.

5. The ground vibration noise common mode rejection method according to claim 1, further comprising the steps of: and introducing the correction transfer function at the rear end of the output signal of the micro-thrust measuring system or the vibration sensor to synchronize the outputs of the micro-thrust measuring system and the vibration sensor in the concerned frequency band.

6. The ground vibration noise common mode rejection method according to claim 1, wherein the step of demodulating the demodulated signal with the output of the micro thrust measurement system is represented by:

in the formula, A_sRepresenting a characteristic signal amplitude; b is₁The gain of the micro-thrust measurement system is shown,representing the phase delay of the micro thrust measurement system,representing the phase shift of the micro thrust measurement system; performing direct current quantity extraction on the demodulated signal to obtain the second half of the above formula; the above formula is divided to obtain:

obtaining phase information by arctangent calculationThe above formula is subjected to a square sum operation to obtain:

obtaining amplitude information A by the above formula evolution operation_sB₁。

7. A ground vibration noise common mode suppression system based on a vibration sensor is applied to the ground vibration noise common mode suppression method based on the vibration sensor, which is characterized by comprising a micro-thrust measurement system, the vibration sensor, a fixed platform, a piezoelectric driver and a controller, wherein:

the micro-thrust measuring system and the vibration sensor are fixedly connected to the fixed platform; the piezoelectric drivers are arranged at different positions on the fixed platform and are used for driving the fixed platform to move;

the controller is respectively connected with the micro-thrust measuring system and the vibration sensor, is used for adjusting and optimizing control parameters of the micro-thrust measuring system to enable a transfer function of the control parameters to be a certain value in a frequency range of interest, is used for receiving the output of the micro-thrust measuring system and the vibration sensor and analyzing data, and matches a single sensitive axis of the micro-thrust measuring system with a coordinate axis of the vibration sensor;

the controller generates a driving signal with characteristic frequency and transmits the driving signal to the piezoelectric driver, the piezoelectric driver drives the platform to move in the direction of the sensitive axis, and the controller reads and records the output of the micro-thrust measuring system and the output of the vibration sensor; and simultaneously, the controller generates unit orthogonal demodulation signals with the same frequency and phase as the driving signals, the demodulation signals are respectively demodulated with the output of the micro-thrust measuring system and the vibration sensor, the controller extracts amplitude ratio and phase difference information of the output results of the micro-thrust measuring system and the vibration sensor, and after the comparison information of enough frequency points is accumulated, a high-precision correction transfer function is obtained by fitting, so that the output of the micro-thrust measuring system and the output of the vibration sensor are synchronous, and vibration noise is further deducted through a common mode.

8. The ground vibration noise common mode rejection system of claim 7, wherein the vibration sensor comprises a three-axis vibrometer, a closed-loop vibration sensor, or an accelerometer with multiple degrees of freedom.

Background

The precise space science task needs a high-precision non-towing technology to provide an ultra-static and ultra-stable satellite platform, the high-precision performance test of an executor, namely a micro-thruster in a non-towing control loop is the key for non-towing control optimization, and the study of a precise micro-thruster transfer function model is the key for non-towing algorithm optimization. At present, most research mechanisms adopt a torsion pendulum structure, and besides the characteristic of high sensitivity, the influence of vibration noise of the ground on the translational degree of freedom on the torsional degree of freedom of the torsion balance is small. However, the torsional pendulum eigenfrequency is low (generally less than 0.1Hz), and the wide bandwidth requirement for carrying out high-frequency dynamic tests cannot be met. In order to provide a comprehensive and accurate dynamic system model for drag-free control, a wide-bandwidth micro-thrust measuring device generally adopts a suspended pendulum structure to expand the system measurement bandwidth to be more than 10 Hz. The structure is sensitive to ground vibration noise parallel to the direction of pendulum motion, which puts high demands on the experimental environment. In a general experimental environment, the ground vibration noise is a main limiting factor influencing the micro-thrust test, and is influenced by the ground vibration noise, the thrust measurement noise can reach 0.1mN magnitude within a frequency band of 0.1Hz to 10Hz, and is 2 to 3 magnitudes higher than the level of the submicron thrust noise provided by a space gravitational wave detection task, so that the influence of the ground noise is not negligible in the submicron thrust test.

In recent years, the domestic space satellite technology has been leaped forward suddenly, the first in-orbit no-drag control technology test in China was successfully carried out on the Chinese academy of sciences microgravity satellite 'Tai Ji I' launched at the end of 8 months in 2019, and the in-orbit no-drag technology was also verified by the 'Tianqin I' test satellite launched next to 12 months in 2019. Therefore, the development of the micro-thrust test oriented to the drag-free control is one of the key points of the subsequent high-precision space scientific experiment attention, and the inhibition of the influence caused by the ground vibration noise is a key problem to be solved in the broad bandwidth test of the submicron-Newton-level micro-thruster.

Disclosure of Invention

The invention provides a ground vibration noise common mode suppression method based on a vibration sensor and a ground vibration noise common mode suppression system based on the vibration sensor, aiming at overcoming the problem that the ground noise causes non-negligible influence on the broad bandwidth test of a submicron-Newton-level micro-thruster in the prior art.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a ground vibration noise common mode rejection method based on a vibration sensor comprises the following steps:

fixedly connecting a micro-thrust measuring system and a vibration sensor to the same platform;

the platform is driven to move by piezoelectric drivers arranged at different positions on the platform, and a single sensitive axis of the micro-thrust measuring system is matched with a coordinate axis of the vibration sensor by comparing output results of the micro-thrust measuring system and the vibration sensor;

a driving signal with characteristic frequency f is externally generated and transmitted to a piezoelectric driver, the piezoelectric driver drives the platform to move in the direction of a single sensitive axis of the micro-thrust measuring system, and the outputs of the micro-thrust measuring system and the vibration sensor are respectively recorded; and simultaneously, externally generating unit orthogonal demodulation signals with the same frequency and phase as the driving signals, demodulating the demodulation signals with the outputs of the micro-thrust measuring system and the vibration sensor respectively, extracting amplitude ratio and phase difference information of output results of the micro-thrust measuring system and the vibration sensor, fitting to obtain a high-precision correction transfer function after accumulating comparison information of enough frequency points, synchronizing the outputs of the micro-thrust measuring system and the vibration sensor, and further deducting vibration noise through a common mode.

Preferably, the step of matching a single sensitive axis of the micro thrust measurement system with a coordinate axis of the vibration sensor includes: the platform is driven to move by a piezoelectric driver, the gravity acceleration component is used for calibration, the output of the micro-thrust measurement system is decomposed to the coordinate axis of the vibration sensor, the correlation in each axial direction is analyzed, and the coefficient of the micro-thrust measurement system in each direction is determined; the expression formula is as follows:

F_out＝K_iF_I+K_oF_O+K_pF_P

in the formula, F_I、F_O、F_PIndicating the output of three coordinate axes of the vibration sensor by adjusting K_i、K_o、K_pAnd the micro-thrust measurement system is matched with the coordinate axis of the vibration sensor according to the coefficient in the coordinate axis direction.

Preferably, in the process of matching the micro thrust measurement system with the vibration sensor, the method further comprises the following steps: and rotating and finely adjusting the micro-thrust measuring system and the vibration sensor to ensure that a sensitive shaft of the micro-thrust measuring system and a shaft of the vibration sensor are respectively consistent with the motion direction of the platform.

Preferably, the step of rotationally fine-tuning the micro thrust measurement system and the vibration sensor comprises: and when the driving signals are applied to the platform in different directions, the micro-thrust testing system and the vibration sensor are rotated and finely adjusted respectively, so that the output values of the micro-thrust testing system and the vibration sensor in the same input signal direction are maximum, and the output value in the orthogonal direction is minimum.

Preferably, a correction transfer function is introduced to the rear end of an output signal of the micro thrust measurement system or the vibration sensor, so that the output of the micro thrust measurement system or the vibration sensor in the concerned frequency band is finally synchronous, and the common mode deduction of vibration noise can be facilitated.

As a preferred methodUsing an externally generated drive signal A with a characteristic frequency f_ssin (2 pi ft) and unit quadrature demodulation signals sin (2 pi ft), cos (2 pi ft), wherein the characteristic signal drives the piezoelectric driver to drive the platform to move, and the process brings phase shiftAnd then outputs with different amplitudes and phases are obtained through a micro-thrust test system and a vibration sensor.

Amplitude information and phase information can be respectively extracted by using the unit orthogonal demodulation signal, wherein in the case of a micro thrust measurement system, the output demodulation process can be expressed as:

in the formula, B₁The gain of the micro-thrust measurement system is shown,phase delay of the micro thrust measurement system; the demodulated signal is subjected to direct current extraction to obtain the second half of the equation. The two are divided to obtain:

calculating to obtain tangent value, and performing arc tangent operation to obtain phase information

The above formula is subjected to a square sum operation to obtain:

obtaining amplitude information A after the above formula evolution operation_sB₁. In the same way, the demodulation result output by the vibration sensor and the phase difference and amplitude ratio information output by the two paths can be obtained.

The invention also provides a ground vibration noise common mode rejection system based on the vibration sensor, which is applied to the ground vibration noise common mode rejection method provided by any technical scheme, and the ground vibration noise common mode rejection system specifically comprises a micro-thrust measurement system, the vibration sensor, a fixed platform, a piezoelectric driver and a controller, wherein: the micro-thrust measuring system and the vibration sensor are fixedly connected to the fixed platform; the piezoelectric drivers are arranged at different positions on the fixed platform and are used for driving the fixed platform to move; the controller is respectively connected with the micro-thrust measuring system and the vibration sensor, is used for adjusting and optimizing control parameters of the micro-thrust measuring system to enable a transfer function of the control parameters to be a certain value in a frequency range of interest, is used for receiving the output of the micro-thrust measuring system and the vibration sensor and analyzing data, and matches a single sensitive axis of the micro-thrust measuring system with a coordinate axis of the vibration sensor;

the controller generates a driving signal with characteristic frequency and transmits the driving signal to the piezoelectric driver, the piezoelectric driver drives the platform to move in the direction of the sensitive axis, and the controller reads and records the output of the micro-thrust measuring system and the output of the vibration sensor; and simultaneously, the controller generates unit orthogonal demodulation signals with the same frequency and phase as the driving signals, the demodulation signals are respectively demodulated with the output of the micro-thrust measuring system and the vibration sensor, the controller extracts amplitude ratio and phase difference information of the output results of the micro-thrust measuring system and the vibration sensor, and after the comparison information of enough frequency points is accumulated, a high-precision correction transfer function is obtained by fitting, so that the output of the micro-thrust measuring system and the output of the vibration sensor are synchronous, and vibration noise is further deducted through a common mode.

Preferably, the vibration sensor comprises a three-axis micro-vibration meter, a closed-loop vibration sensor or a multi-degree-of-freedom accelerometer.

Compared with the prior art, the technical scheme of the invention has the beneficial effects that: the invention adopts the vibration sensor to monitor the ground vibration, and utilizes the high-precision matching technology to carry out static and dynamic matching on the micro-thrust measuring system and the vibration sensor, thereby realizing higher-precision common mode suppression of ground vibration noise.

Drawings

Fig. 1 is a flowchart of a method for suppressing a ground vibration noise common mode based on a vibration sensor according to embodiment 1.

Fig. 2 is a schematic diagram of the micro thrust measurement system of embodiment 1 matched with a vibration sensor in a crossed axis manner.

Fig. 3 is a schematic diagram of a measurement scheme of the high-precision correction transfer function of example 1.

Fig. 4 is an example of the experimental results of example 1.

Fig. 5 is a schematic structural diagram of a ground vibration noise common mode rejection system based on a vibration sensor in embodiment 2.

Detailed Description

The drawings are for illustrative purposes only and are not to be construed as limiting the patent;

for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product;

it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.

Example 1

The present embodiment provides a method for suppressing ground vibration noise common mode based on a vibration sensor, as shown in fig. 1, which is a flowchart of the method for suppressing ground vibration noise common mode based on a vibration sensor according to the present embodiment.

The ground vibration noise common mode rejection method based on the vibration sensor provided by the embodiment comprises the following steps:

s1: the micro-thrust measuring system 1 and the vibration sensor 2 are fixedly connected to the same platform 3.

In this embodiment, the vibration sensor 2 is a three-axis micro-vibration meter.

S2: the platform 3 is driven to move by piezoelectric drivers 4 arranged at different positions on the platform 3, and a single sensitive axis of the micro-thrust measuring system 1 is matched with a coordinate axis of the vibration sensor 2 by comparing output results of the micro-thrust measuring system 1 and the vibration sensor 2.

In this embodiment, the cross coupling influence caused by different coordinate systems and installation errors is considered, and the final purpose is to match the micro thrust measurement system 1 with the fixedly connected vibration sensor 2, so that the output of the micro thrust measurement system 1 is decomposed to three coordinate axes of the vibration sensor 2 in this embodiment, that is, a single sensitive axis of the micro thrust measurement system 1 is projected to the three coordinate axes of the vibration sensor 2.

Fig. 2 is a schematic diagram of the micro thrust measurement system 1 and the vibration sensor 2 in the present embodiment, which are matched with each other in a crossed manner.

Specifically, the platform 3 is driven to move by the piezoelectric driver 4, calibration is performed by using a gravity acceleration component, the output of the micro-thrust measurement system 1 is decomposed to the coordinate axis of the vibration sensor 2, the correlation in each axial direction is analyzed, the coefficient of the micro-thrust measurement system 1 in each direction is determined, and the output F of the micro-thrust measurement system 1 is_outThe expression formula of (a) is:

F_out＝K_iF_I+K_oF_O+K_pF_P

in the formula, F_I、F_O、F_PIndicating the output of the three coordinate axes of the vibration sensor 2 by adjusting K_i、K_o、K_pAnd the coefficient of the micro-thrust measurement system 1 corresponding to the direction of the coordinate axis is matched with the coordinate axis of the vibration sensor 2.

The above steps can be expressed as a static matching process of the micro thrust measuring system 1 and the vibration sensor 2.

In another embodiment, in the process of matching the micro thrust measuring system 1 with the vibration sensor 2, the following steps are included: and rotating and finely adjusting the micro thrust measuring system 1 and the vibration sensor 2 to ensure that a sensitive shaft of the micro thrust measuring system 1 and a shaft of the vibration sensor 2 are respectively consistent with the motion direction of the platform 3.

Wherein, the step of rotating and finely adjusting the micro thrust measuring system 1 and the vibration sensor 2 comprises: when the driving signals are applied to the platform 3 in different directions, the micro-thrust testing system and the vibration sensor 2 are rotated and finely adjusted respectively, so that the output values of the micro-thrust testing system 1 and the vibration sensor 2 in the same input signal direction are maximum, and the output values in the orthogonal direction are minimum.

At the moment, the static matching of the micro-thrust system and the vibration sensor 2 is completed, and the cross shaft coupling effect can be effectively reduced.

S3: a driving signal with characteristic frequency f is externally generated and transmitted to a piezoelectric driver 4, the piezoelectric driver 4 drives the platform 3 to move in the direction of a single sensitive axis of the micro-thrust measuring system 1, and the outputs of the micro-thrust measuring system 1 and the vibration sensor 2 are respectively recorded; and simultaneously, externally generating unit orthogonal demodulation signals with the same frequency and phase as the driving signals, demodulating the demodulation signals with the outputs of the micro-thrust measuring system 1 and the vibration sensor 2 respectively, and extracting the amplitude ratio and the phase difference information of the output results of the micro-thrust measuring system 1 and the vibration sensor 2.

In the embodiment, a driving signal and a demodulation signal with the same frequency and the same phase are generated, wherein the driving signal far exceeds the ground vibration level to push the platform to move, and the demodulation signal is a unit orthogonal signal; and outputting the signals after passing through a micro-thrust measuring system and a vibration detecting system, orthogonally demodulating the outputs of the two systems and a demodulation signal, extracting amplitude information and phase information in the signals, obtaining an amplitude ratio by an amplitude result, and obtaining a phase difference by a phase result.

Using externally generated characteristic drive signals A_ssin (2 pi ft) and unit orthogonal demodulation signals sin (2 pi ft) and cos (2 pi ft), wherein the characteristic signals drive the PZT to push the platform 3 to move, and the process brings phase shiftThen passes through a micro-thrust test system and the groundDifferent amplitudes and phase outputs are obtained after the system is vibrated.

The amplitude and phase information can be respectively extracted by utilizing the orthogonal demodulation signal, in this embodiment, taking the micro thrust measurement system as an example, the output demodulation process can be expressed as:

in the formula, A_sRepresenting the amplitude of the characteristic signal, B₁Denotes the gain, A, of the micro-thrust measurement system 1_sAnd B₁The product of (a) represents the magnitude information;the micro-thrust measures the phase delay of the system 1. The demodulated signal is subjected to direct current extraction to obtain the second half of the equation. And the two are divided:

obtaining tangent value and phase information by arc tangent operationAnd performing square sum operation on the two:

obtaining amplitude information A after evolution_sB₁。

In the same way, the demodulation result output by the vibration sensor 2 and the phase difference and amplitude ratio information output by the two paths can be obtained.

S4: after the comparison information of enough frequency points is accumulated, a high-precision correction transfer function is obtained through fitting, so that the output of the micro-thrust measuring system 1 and the output of the vibration sensor 2 are synchronous, and the vibration noise is further deducted through a common mode.

The accumulated comparison information is generally more than 10 frequency points in the concerned frequency band, and is used for fitting a complete correct transfer function.

In this embodiment, considering that the transfer functions of the micro thrust measurement system 1 and the vibration sensor 2 are different, and the amplitudes and phases of the outputs of the two are different under the same input noise, the correction transfer function is added to synchronize the outputs of the micro thrust measurement system 1 and the vibration sensor 2. In this embodiment, a correction transfer function is introduced to the rear end of the output signal of the micro thrust measurement system or the vibration sensor, so that the output of the micro thrust measurement system and the output of the vibration sensor are finally synchronous in the concerned frequency band, and the common mode can be facilitated to subtract the vibration noise. Fig. 3 shows a measurement scheme of the modified transfer function of the present example.

Further, the present embodiment continues to utilize PZT to generate a signal with a characteristic frequency, compare the input signal, add the signal after subtraction of the correction transfer function, and evaluate the common mode rejection capability.

After high-precision matching is completed, the common-mode noise rejection capability l (f) at the characteristic frequency can be expressed as:

in the formula, A_sig(f) And (f) represents the amplitude of the characteristic signal at the frequency f of the characteristic signal, and N (f) is the amplitude of noise at the frequency f of the characteristic signal after matching is finished. The platform 3 can be continuously pushed by the piezoelectric driver 4, the input signals are compared, signals obtained after correction transfer function deduction are added, and the common-mode rejection capability is evaluated. When the matching subtraction is complete, the ground vibration noise is expected to be suppressed to the measurement background of the vibration sensor 2.

In the implementation, the time domain results of the preliminary experiment are shown in fig. 4, in which the vibration sensor 2 employs an accelerometer. In fig. 4, a broken line segment with a square mark represents a vibration signal measured by the micro thrust measuring system 1, and a solid line segment with a circular mark represents a vibration signal sensed by the vibration sensor 2; the curve marked by the star represents the signal after matching subtraction of the micro thrust measuring system 1 and the vibration sensor 2. As can be seen from fig. 4, in the present embodiment, the effect of suppressing the vibration noise is significant in the laboratory environment.

In the embodiment, the vibration sensor 2 is adopted for ground vibration monitoring, and the micro-thrust measurement system 1 and the vibration sensor 2 are statically and dynamically matched by using a high-precision matching technology, so that the common-mode suppression of ground vibration noise is realized. And finally, in a measurement frequency band within 20Hz, the influence of ground vibration noise is reduced to a submicron Newton level so as to meet the requirement on ground test of the micro-thruster in high-precision drag-free control optimization. Also, this method can be migrated to the ground for experiments and studies affected by ground vibration.

Example 2

The present embodiment proposes a ground vibration noise common mode rejection system based on a vibration sensor, which is applied to the ground vibration noise common mode rejection method based on the vibration sensor proposed in embodiment 1. Fig. 5 is a schematic diagram for reference of the structure of the ground vibration noise common mode rejection system based on the vibration sensor according to the present embodiment.

In the ground vibration noise common mode rejection system based on the vibration sensor provided by this embodiment, the system includes a micro thrust measurement system 1, a vibration sensor 2, a fixed platform 3, a piezoelectric driver 4, and a controller 5, wherein: the micro-thrust measuring system 1 and the vibration sensor 2 are fixedly connected to the fixed platform 3; the piezoelectric drivers 4 are arranged at different positions of the fixed platform 3 and are used for driving the fixed platform 3 to move.

The controller 5 is respectively connected with the micro-thrust measuring system 1 and the vibration sensor 2, and is used for adjusting and optimizing control parameters of the micro-thrust measuring system 1 to enable a transfer function of the control parameters to be a certain value in a concerned frequency band, receiving the output of the micro-thrust measuring system 1 and the output of the vibration sensor 2, analyzing data, and matching a single sensitive axis of the micro-thrust measuring system 1 with a coordinate axis of the vibration sensor 2.

The controller 5 generates a driving signal with characteristic frequency and transmits the driving signal to the piezoelectric driver 4, the piezoelectric driver 4 drives the platform 3 to move in the direction of the sensitive axis, and the controller 5 reads and records the output of the micro-thrust measuring system 1 and the output of the vibration sensor 2; meanwhile, the controller 5 generates unit orthogonal demodulation signals with the same frequency and phase as the driving signals, the demodulation signals are respectively demodulated with the output of the micro-thrust measuring system 1 and the output of the vibration sensor 2, the controller 5 extracts amplitude ratio and phase difference information of the output results of the micro-thrust measuring system 1 and the output results of the vibration sensor 2, after the comparison information of enough frequency points is accumulated, a high-precision correction transfer function is obtained through fitting, the outputs of the micro-thrust measuring system 1 and the vibration sensor 2 are synchronous, and vibration noise is further deducted through a common mode.

In this embodiment, the vibration sensor 2 is a three-axis micro-vibration meter, a closed-loop vibration sensor, or a multi-degree-of-freedom accelerometer, the piezoelectric actuator 4 is a piezoelectric ceramic actuator (PZT), and the controller 5 is a closed-loop control system.

The same or similar reference numerals correspond to the same or similar parts;

the terms describing positional relationships in the drawings are for illustrative purposes only and are not to be construed as limiting the patent;

it should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.