An accelerometer performance testing device, method and system

Abstract

The present invention discloses an accelerometer performance testing device, method and system, belonging to the technical field of high-precision inertial sensor testing. Based on a four-wire pendulum active vibration isolation system, the present invention can reduce the influence of ground vibration noise on the residual vibration of the pendulum table, and provide a test environment with low noise in the order of 10-9 m / s2 in the horizontal direction for the accelerometer to be tested. The present invention uses a displacement monitoring instrument to record the horizontal displacement change of the pendulum table, which can be used as a theoretical input after calibration, and compares the amplitude spectrum with the measured acceleration data of the accelerometer to be tested in the calibration direction. By changing the amplitude and frequency of the injected electromagnetic excitation signal, the performance test results of the accelerometer to be tested are obtained, realizing the resolution test and sensitivity calibration of the horizontal axis of the high-precision accelerometer in the frequency band of 0.1 Hz to 1 Hz in the order of 10-9 m / s2. It also has the advantages of providing a low-noise environment and being able to measure the acceleration response of the accelerometer at different frequencies.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-precision inertial sensor testing, and more specifically, relates to an accelerometer performance testing device, method, and system. Background Art

[0002] The resolution of high-precision space electrostatic accelerometers is usually above 10 -9 m / s 2 and has been successfully applied many times as an important payload in satellite gravity measurement projects at home and abroad. The research on higher-precision space inertial sensors has become one of the important research tasks in the field of space science. Conducting a comprehensive test on the functional performance of high-precision electrostatic accelerometers on the ground is an essential step before their in-orbit application. Among them, the high-voltage suspension test method uses the electrostatic force to balance the gravity of the accelerometer's proof mass, which is an important method in its ground test and can be used to test and verify the performance such as the resolution and sensitivity of the accelerometer's horizontal axis.

[0003] Traditional accelerometer resolution test and sensitivity calibration methods are no longer applicable to accelerometers with a resolution of 10 -9 m / s 2 or even higher precision. Moreover, the performance test level of the high-voltage suspension experiment of high-precision space electrostatic accelerometers is often limited by factors such as ground vibration. Therefore, to further improve the test and evaluation level of the main performance parameters of accelerometers, it is necessary to improve the existing accelerometer performance test methods, provide a test platform with low vibration noise, complete the functional inspection, horizontal axis resolution test, and sensitivity coefficient calibration of accelerometers, which will provide important support for the ground test of space inertial sensors and their applications in fields such as satellite gravity measurement. In addition, the performance tests of inertial sensors such as MEMS accelerometers, seismographs, and gravimeters, including their resolution and sensitivity, also rely on high-performance vibration isolation devices and calibration test systems. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide an accelerometer performance testing device, method, and system, aiming to solve the problem that traditional accelerometer resolution test and sensitivity calibration methods are no longer applicable to accelerometers with a resolution of 10 -9 m / s 2 or even higher precision.

[0005] To achieve the above purpose, in the first aspect, the present invention provides an accelerometer performance testing device, including: a support frame, four equal-length suspension wires, a vibration isolation platform, several motion sensors, an active vibration isolation controller, a drive controller, several electromagnetic drivers, and a displacement monitoring instrument;

[0006] One end of the suspension wire is fixed to the cross beam on the support frame, and the other end is connected to the vibration isolation platform for suspending the vibration isolation platform. Its length can ensure that the four-wire pendulum can move along two translational degrees of freedom in the horizontal direction;

[0007] The accelerometer to be measured is fixedly placed at the central position of the vibration isolation platform surface;

[0008] The several motion sensors are used to obtain the absolute velocity information of the vibration isolation platform and output it to the active vibration isolation controller;

[0009] The active vibration isolation controller is used to generate an active vibration isolation control signal according to the absolute velocity information of the vibration isolation platform, and then generate a corresponding current through the signal conditioning circuit and output it to the electromagnetic actuator;

[0010] The drive controller is used to generate a sinusoidal voltage signal with an amplitude of A and a calibrated required frequency of f a and generate a corresponding current through the signal conditioning circuit and output it to the electromagnetic actuator;

[0011] The several electromagnetic actuators are used to first receive the current generated by the active vibration isolation controller to form a feedback force for reducing the vibration degree of the vibration isolation platform. After the vibration isolation of the vibration isolation platform enters the optimal state, they receive the current generated by the drive controller and form an electromagnetic driving force with the calibrated required frequency f a based on the magnetic force transmission principle to drive the vibration isolation platform to generate translational displacement changes along the calibrated direction;

[0012] The displacement monitoring instrument is used to monitor and record the displacement data of the vibration isolation platform in two translational degrees of freedom in the horizontal direction;

[0013] The support frame, four equal-length suspension wires and the vibration isolation platform together constitute a passive vibration isolation structure, and together with the motion sensors, the active vibration isolation controller and the electromagnetic actuators, they constitute an active vibration isolation system, enabling the vibration isolation system to have the function of isolating ground vibration noise in the horizontal direction in the frequency band of 0.1 - 10 Hz.

[0014] Preferably, the electromagnetic actuator includes: a permanent magnet installed on the surface of the vibration isolation platform and an electromagnetic coil installed along the direction of the permanent magnet and on the ground-fixed base;

[0015] Preferably, the several electromagnetic actuators include:

[0016] The first electromagnetic actuator is located on the east-west axis of the vibration isolation platform to control the translational degree of freedom movement of the vibration isolation platform in the east-west direction;

[0017] The second electromagnetic actuator and the third electromagnetic actuator are symmetrically arranged on both sides of the north-south axis of the vibration isolation platform to jointly control the translational degree of freedom movement and the rotational degree of freedom movement of the vibration isolation platform in the north-south direction at the same time.

[0018] Preferably, the device further includes: a magnetic shielding cover;

[0019] The magnetic shielding cover covers the electromagnetic driver and is used to shield the magnetic field interference or magnetic leakage generated by the electromagnetic driver on the accelerometer under test.

[0020] To achieve the above object, in a second aspect, the present invention provides an accelerometer performance test method, which is applied to the accelerometer performance test device described in the first aspect. The method includes:

[0021] After the vibration isolation platform enters the optimal state of vibration isolation and the output data of the accelerometer under test is stable, obtain the output data of the displacement monitoring instrument and the accelerometer under test in the same time period;

[0022] Perform differential processing on the output data of the displacement monitoring instrument to obtain the translational acceleration signal of the vibration isolation platform, and further perform amplitude spectrum calculation on this signal as the theoretical output amplitude of the acceleration;

[0023] Compare the amplitude spectra of the theoretical acceleration and the measured acceleration of the accelerometer under test in the calibration direction to determine whether they match within the error range, and obtain the resolution test result of the accelerometer under test.

[0024] Preferably, the method further includes:

[0025] By linearly fitting the amplitude spectra of the response accelerations of the accelerometer under test and the displacement monitoring instrument under different amplitude electromagnetic excitation signals, obtain the sensitivity calibration result of the accelerometer under test.

[0026] Preferably, the method further includes:

[0027] By changing the frequency of the injected electromagnetic excitation signal, analyze the transfer function or low-frequency response characteristics of the accelerometer under test.

[0028] To achieve the above object, in a third aspect, the present invention provides an accelerometer performance test system, including: the accelerometer performance test device described in the first aspect, a memory, and a processor;

[0029] The memory is used to store computer programs and execution instructions;

[0030] The processor is used to execute the computer execution instructions. When the computer program runs on the processor, the method described in the second aspect is executed.

[0031] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the following beneficial effects are obtained:

[0032] (1) The present invention provides an accelerometer performance testing device, which is based on a four-wire pendulum active vibration isolation system and can reduce the influence of ground vibration noise on the residual vibration of the pendulum table, providing a low-noise testing environment with a magnitude of 10 -9 m / s 2 in the horizontal direction for the accelerometer under test. By using a non-contact electromagnetic driver, electromagnetic excitation signals can be provided in the two translational degrees of freedom directions of the pendulum table in the horizontal plane. In addition, compared with a contact driver that will hinder the free movement of the vibration isolation pendulum table and thus affect the system performance, the non-contact driver has less interference, and has the characteristics of a larger output range and no hysteresis phenomenon, and is more suitable for the active vibration isolation system in the field of precision measurement.

[0033] (2) The present invention provides an accelerometer performance testing method, which uses a displacement monitoring instrument to record the horizontal displacement change of the pendulum table. After calibration, it can be used as the theoretical input, and the amplitude spectrum is compared with the measured acceleration data of the accelerometer under test in the calibration direction. Finally, by changing the amplitude and frequency of the injected excitation signal, the performance of the accelerometer under test can be tested, realizing the resolution test and sensitivity calibration of the horizontal axis of a high-precision accelerometer in the frequency band of 0.1 Hz to 1 Hz with a magnitude of 10 -9 m / s 2 It also has the advantages of providing a low-noise environment and being able to measure the acceleration responses of the accelerometer at different frequencies. Description of the Drawings

[0034] Figure 1 is a schematic structural diagram of a high-precision accelerometer performance testing device provided by the present invention.

[0035] Figure 2 is a front view of a high-precision accelerometer performance testing device provided by the present invention.

[0036] Figure 3 is a flowchart of an accelerometer performance testing method provided by the present invention.

[0037] In all the drawings, the same reference numerals are used to represent the same elements or structures, where:

[0038] 1 - Support frame; 2 - Suspension wire; 3 - Vibration isolation platform; 4 - Motion sensor; 5 - Controller; 6 - Electromagnetic driver; 7 - Displacement monitoring instrument; 8 - Accelerometer under test; 9 - Data processing system; 10 - Magnetic shielding cover; 51 - Active vibration isolation controller; 52 - Drive controller; 53 - Signal conditioning circuit; 61 - Permanent magnet; 62 - Ground-fixed base; 63 - Electromagnetic coil; 91 - Data processing module; 92 - Result display module. Detailed Embodiments

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] As Figure 1 and Figure 2 shown, the present invention provides a high-precision accelerometer performance testing device, including: a support frame 1, four equal-length suspension wires 2, a vibration isolation platform 3, a plurality of motion sensors 4, a controller 5, a plurality of electromagnetic drivers 6, a displacement monitoring instrument 7, a to-be-tested accelerometer 8, a data processing system 9, and a magnetic shielding cover 10.

[0041] The support frame 1 is placed on a flat ground. The upper part of the suspension wire 2 is fixed to the cross beam of the support frame 1 (screws and connecting plates), and the lower part is connected to the connecting plate of the vibration isolation platform 3 (wire rope clamping device) to suspend the vibration isolation platform. On the tabletop of the vibration isolation platform 3, a first motion sensor, a second motion sensor, and the to-be-tested accelerometer 8 are respectively placed. The first motion sensor and the second motion sensor are symmetrically placed on both sides of the to-be-tested accelerometer 8, and a third motion sensor is placed on the ground near the vibration isolation platform 3, and its signal output end is connected to the signal input end of the data processing system 9. The signal output end of the controller 5 is connected to the signal input end of the electromagnetic driver 6, the signal output end of the electromagnetic driver 6 is connected to the signal input end of the vibration isolation platform 3, the signal output end of the displacement monitoring instrument 7 is connected to the signal input end of the data processing system 9, and the to-be-tested accelerometer 8 is fixed at the central position of the tabletop of the vibration isolation platform 3, and its signal output end is connected to the signal input end of the data processing system 9. The magnetic shielding cover 10 is located on both sides of the vibration isolation platform and covers part of the electromagnetic driver 6, and is used to shield the magnetic field interference or magnetic leakage generated by it to the to-be-tested accelerometer 8, etc., but leaves space for the magnetic force transmission process. Finally, the final resolution test and sensitivity calibration results are obtained through calculation and analysis by the data processing system 9.

[0042] Specifically, as Figure 1 and Figure 2 shown, the support frame 1, the equal-length suspension wires 2 and the vibration isolation platform 3 form a two-axis translational four-wire pendulum structure based on a single pendulum model. The vibration isolation platform 3 is an optical platform. The suspension wires are long enough so that the four-wire pendulum can move along two translational degrees of freedom in the horizontal direction and has a vibration isolation function for ground vibration noise in the horizontal direction with a frequency band of 0.1 - 10 Hz. The vibration isolation performance is determined by the ratio of the residual vibration acceleration noise spectral density on the tabletop of the vibration isolation platform to the vibration acceleration noise spectral density of the ground near the location of the vibration isolation platform during the same time period. The two translational degrees of freedom in the horizontal direction refer to the horizontal y and z directions, corresponding to the east-west and north-south plane directions respectively.

[0043] The number of the motion sensors 4 is three, including seismographs symmetrically placed on both sides of the accelerometer 8 to be measured and on the ground near the vibration isolation platform (the noise power spectral density is required to reach 10 -10 m / s 2 / Hz 1 / 2 magnitude), which can record the residual vibration acceleration noise on the vibration isolation platform and the vibration data of the ground near the vibration isolation platform in real time, and finally give information such as the residual vibration acceleration noise spectrum curve on the vibration isolation platform 3 and its vibration isolation rate for the ground vibration. By using two symmetrically placed seismographs, on the one hand, the translational degree of freedom of the accelerometer can be verified by common mode for the read data, and on the other hand, the torsional degree of freedom of the accelerometer can be verified by differential mode for the read data. Balance the centroid of the vibration isolation platform to make it coincide with the geometric center as much as possible, which is convenient for obtaining the correct torsional signal.

[0044] The controller 5 includes an active vibration isolation controller 51, a drive controller 52 and a signal conditioning circuit 53. The active vibration isolation controller 51 is used to generate an active vibration isolation control voltage signal according to the absolute velocity information of the vibration isolation platform. The drive controller 52 provides a single-frequency sine input signal as the drive voltage signal, and the amplitude and frequency of this signal can be changed according to the needs of performance testing. After receiving the voltage signal, the signal conditioning circuit 53 generates a current.

[0045] The electromagnetic drive 6 includes a permanent magnet 61 installed on the tabletop of the four-wire pendulum vibration isolation platform and an electromagnetic coil 63 installed on the ground-fixed base 62 along the direction of the permanent magnet 61. The electromagnetic drive 6 mainly works based on the principle of magnetic force transmission. When an electric current is passed through the electromagnetic coil 63, a force will act between the permanent magnet 61 and the electromagnetic coil 63. By changing the direction of the current, the switching between the thrust and the attraction force of the two can be realized, so that the vibration isolation platform 3 generates a corresponding displacement, and the accelerometer 8 to be measured located on the vibration isolation platform also generates a horizontal displacement and outputs an acceleration signal accordingly. The electromagnetic drive 6 has the characteristics of wide working frequency band, high precision, fast response speed, large output force and large displacement, and is very suitable for precision measurement experiments in the low-frequency range. In this embodiment, a smaller cylindrical permanent magnet with a diameter of 10 mm and a length of 12 mm is used, so as to increase the gap between the magnet and the coil to 3.5 mm.

[0046] The displacement monitoring instrument 7 is used to monitor the displacement of the vibration isolation platform 3, including but not limited to a laser interferometer, an autocollimator, etc.

[0047] The accelerometer 8 to be measured outputs a horizontal axis acceleration signal.

[0048] The data processing system 9 includes a data processing module 91 and a result display module 92. The data processing module 91 is used to perform differential calculation on the output data of the displacement monitoring instrument 7, and process the data of the accelerometer under test 8 and the translational acceleration of the vibration isolation platform; the result display module 92 is used to display the data processing results of the accelerometer under test 8 and the displacement monitoring instrument 7.

[0049] The magnetic shielding cover 10 is located on both sides of the vibration isolation platform, connected to the ground-fixed base 62, covering the permanent magnet 61, the ground-fixed base 62 and the electromagnetic coil 63, and leaving a space for the magnetic force transmission process. Its surface is covered with magnetic shielding material, which is used to shield the magnetic field interference or magnetic leakage generated by the electromagnetic actuator on the accelerometer under test, etc.

[0050] The working process of the entire performance testing device is as follows: First, a low-noise test environment is provided based on the active vibration isolation system. Then, a single-frequency sine input signal is provided by the drive controller 52 in the controller 5 as the drive voltage signal. After the signal conditioning circuit 53 receives this signal, it generates a current. When the electromagnetic coil 63 is energized with current, a force acts between the permanent magnet 61 and the electromagnetic coil 63. By changing the direction of the current, the switching between the thrust and the attraction force of the two can be realized, so that the vibration isolation platform can generate displacement changes in the two translational degrees of freedom in the horizontal direction. On the one hand, the displacement monitoring instrument 7 is used to monitor the displacement data of the vibration isolation platform 3, and the theoretical input can be calculated through position calibration; on the other hand, the accelerometer under test 8 outputs the horizontal axis acceleration signal. Finally, the data processing system 9 performs differential processing on the output data of the displacement monitoring instrument 7, and performs amplitude spectrum analysis, error calculation and linear fitting on the accelerometer under test 8 and the translational acceleration of the vibration isolation platform. Based on the result display module 92, the resolution test and sensitivity calibration results of the accelerometer under test 8 and the displacement monitoring instrument 7 are displayed.

[0051] As Figure 3 shown, the present invention provides an accelerometer performance testing method, including the following steps:

[0052] S1. Before the experiment, first calibrate the execution force sensitivity coefficient of the electromagnetic actuator by using the current excitation method.

[0053] Fix the permanent magnet at the lower end of the dynamometer, and fix the electromagnetic coil on the base of the spiral side-sway machine table. By adjusting the machine table knob, the dynamometer can be moved up and down, thereby changing the distance between the permanent magnet and the coil. Use a DC regulated power supply to provide current for the coil, and record the readings of the dynamometer when the power supply is turned off and on respectively. According to the difference in readings, the execution force sensitivity coefficient of the electromagnetic actuator composed of the magnet and the coil at a specific distance can be obtained.

[0054] S2. Start the experiment. Place the accelerometer to be measured at the central position of the vibration isolation platform. Use the vibration isolation platform to perform ground active vibration isolation to provide a test environment with low vibration noise.

[0055] First, turn on the power switch of the accelerometer to be measured and observe the output data of the accelerometer received by the data processing system. Then, turn on the active vibration isolation control switch and wait for the vibration isolation performance of the vibration isolation platform to be further improved and stabilized for about 8 - 12 hours (depending on the ground vibration conditions at that time).

[0056] S3. After the vibration isolation of the vibration isolation platform enters the best state and the output data of the accelerometer to be measured is stable, inject a sinusoidal driving voltage (amplitude A mV, frequency f a Hz) through the drive controller. Use the permanent magnet fixedly connected to the tabletop of the four - wire pendulum vibration isolation platform and the electromagnetic coil outside the tabletop to generate an electromagnetic driving force with the required calibration frequency f a to cause a translational displacement change of the vibration isolation platform in the calibration direction.

[0057] First, according to the acceleration input a required for the test of the accelerometer to be measured, then multiply it by the total mass M of the vibration isolation platform and the object placed on the tabletop to obtain the electromagnetic driving force F = M×a required for calibration. Then, according to the electromagnetic driving force F = k×(H vccs ×V), obtain the magnitude of the electromagnetic driving voltage required for calibration, where H vccs is the transfer function of the voltage - controlled current source unit, I = H vccs ×V is the current generated after passing through the signal conditioning circuit, the executive force sensitivity coefficient of the electromagnetic driver is k N / A, and V is the electromagnetic driving voltage required for calibration. In addition, the acceleration responses at different frequency points (such as f b 、f c Hz, etc.) can also be tested according to needs.

[0058] S4. At the same time, record the output data of the displacement monitoring instrument and the accelerometer to be measured.

[0059] The specific steps of S4 include:

[0060] S41. Use the displacement monitoring instrument to monitor the displacement change of the vibration isolation platform, perform differential processing on this displacement data, and obtain the translational acceleration signal of the vibration isolation platform as the theoretical input.

[0061] S42. At the same time, record the output acceleration data of the horizontal axis of the accelerometer to be measured.

[0062] In S4, the vibration isolation platform undergoes a small translational displacement under the drive of electromagnetic force. The accelerometer under test located on the vibration isolation platform outputs dynamic response acceleration data. At the same time, the displacement detection instrument records the displacement data of the vibration isolation platform, and the acceleration signal of the translational motion of the vibration isolation platform is obtained by performing differential processing on this displacement. The specific formula is as follows:

[0063]

[0064] S5. Load the output data of the horizontal axis of the accelerometer under test and the time-domain data of the translational acceleration of the vibration isolation platform recorded during the experiment respectively. Take data within the same time period not less than 1000s for each, and perform FFT on them using the data processing system. The calculation formula is as follows:

[0065]

[0066] In the formula, N represents the length of the data points for FFT calculation in data processing.

[0067] Then divide the corresponding modulus value of each data point (take the first half of the data length, that is, N / 2) after FFT by N / 2 to obtain the actual amplitude of the signal. According to Δf = F s / N to obtain the spectral resolution corresponding to the amplitude.

[0068] S6. Plot the amplitude spectrum curves of the response acceleration signals of the displacement monitoring instrument and the accelerometer under test at the calibration frequency f a respectively, and judge whether there is a peak at the calibration frequency f a to obtain the magnitude of the signal amplitude.

[0069] S7. Calculate the error with an accuracy of 1% for frequency stability. Take the average value of the noise amplitudes in the amplitude spectrum within the frequency range of f a ×(1 ± 1%) Hz (deducting the signal amplitude corresponding to f a ) as the error of the amplitude spectrum, and obtain the amplitude spectrum error results of the accelerometer under test and the translational acceleration of the vibration isolation platform.

[0070] S5 to S7 are all completed in the data processing system.

[0071] S8. Change the injected sinusoidal drive voltage (amplitudes are B, C, D, E mV in sequence, and the corresponding frequencies are all f a Hz) to generate electromagnetic driving forces corresponding to different amplitude excitation signals, and repeat steps S5 to S7.

[0072] In S8, change the amplitude of the excitation signal (the injected amplitudes can be B, C, D, E mV respectively, and the frequencies are all f a Hz) through the drive controller, and detect the response of the accelerometer under test in the horizontal direction.

[0073] S9. According to the metrological specification for resolution testing, within the error range, compare the amplitude spectrum of the acceleration to which the accelerometer under test responds with the translational acceleration of the vibration isolation platform monitored by the displacement monitoring instrument, and perform a linear fit on the response results under different amplitudes of the excitation signal. Finally, obtain the resolution test and sensitivity calibration results of the accelerometer under test.

[0074] In S9 above, the error range of the accelerometer refers to that the ratio of the measured output amplitude to the theoretical output amplitude of the accelerometer under test should be within the range of 50% to 150%.

[0075] In this method, the displacement monitoring instrument monitors the displacement change of the vibration isolation platform. Through differential processing, the translational acceleration signal of the vibration isolation platform can be obtained, and further calculate the amplitude spectrum of this signal as the theoretical output amplitude of the acceleration. Compare the amplitude spectrum of the acceleration to which the accelerometer under test responds with the translational acceleration of the vibration isolation platform monitored by the displacement monitoring instrument within the error range to obtain the resolution test level of the accelerometer under test; by performing a linear fit on the amplitude spectrum of the response acceleration of the accelerometer under test and the displacement monitoring instrument under different amplitudes of the electromagnetic excitation signal, obtain the sensitivity calibration result of the accelerometer under test.

[0076] Those skilled in the art can easily understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An accelerometer performance testing device, characterized in that, Comprising: A support frame, four equal-length suspension wires, a vibration isolation platform, several motion sensors, an active vibration isolation controller, a drive controller, several electromagnetic drivers, and a displacement monitoring instrument; One end of the suspension wire is fixed to the crossbeam on the support frame, and the other end is connected to the vibration isolation platform for suspending the vibration isolation platform. Its length can ensure that the four-wire pendulum can move along the two translational degrees of freedom in the horizontal direction; The accelerometer to be measured is fixedly placed at the central position of the vibration isolation platform tabletop; The several motion sensors are used to obtain the absolute velocity information of the vibration isolation platform and output it to the active vibration isolation controller; The active vibration isolation controller is used to generate an active vibration isolation control signal according to the absolute velocity information of the vibration isolation platform, and then generate a corresponding current through a signal conditioning circuit and output it to the electromagnetic driver; The driving controller is used to generate a sine voltage signal with an amplitude of A and a calibrated required frequency of f a and generate a corresponding current through a signal conditioning circuit and output it to the electromagnetic driver; The plurality of electromagnetic drivers are configured to first receive the current generated by the active vibration isolation controller to form a feedback force for reducing the vibration level of the vibration isolation platform. After the vibration isolation of the vibration isolation platform enters the optimal state, the electromagnetic drivers receive the current generated by the drive controller and form an electromagnetic driving force with the required calibration frequency f based on the principle of magnetic force transmission, driving the vibration isolation platform to generate a translational displacement change along the calibration direction; a ​ The displacement monitoring instrument is used to monitor and record the displacement data of the vibration isolation platform in the two translational degrees of freedom in the horizontal direction; The support frame, the four equal-length suspension wires, and the vibration isolation platform jointly form a passive vibration isolation structure, and together with the motion sensors, the active vibration isolation controller, and the electromagnetic drivers, they form an active vibration isolation system, enabling the vibration isolation system to have the function of isolating ground vibration noise in the horizontal direction in the frequency band of 0.1 - 10 Hz.

2. The device according to claim 1, characterized in that, The electromagnetic driver includes: a permanent magnet installed on the vibration isolation platform tabletop and an electromagnetic coil installed along the direction of the permanent magnet and on the ground-fixed base; 3. The device according to claim 1, characterized in that, The several electromagnetic drivers include: The first electromagnetic driver is located on the east-west axis of the vibration isolation platform and controls the translational degree of freedom motion of the vibration isolation platform in the east-west direction; The second electromagnetic driver and the third electromagnetic driver are symmetrically arranged on both sides of the north-south axis of the vibration isolation platform, and jointly realize the simultaneous control of the translational degree of freedom motion and the rotational degree of freedom motion of the vibration isolation platform in the north-south direction; 4. The device according to any one of claims 1 to 3, characterized in that, The device further includes: a magnetic shielding cover; The magnetic shielding cover covers the electromagnetic driver and is used to shield the magnetic field interference or magnetic leakage generated by the electromagnetic driver on the accelerometer to be measured; 5. An accelerometer performance testing method, applied to the accelerometer performance testing device according to any one of claims 1 to 4, characterized in that, This method includes: After the vibration isolation of the vibration isolation platform enters the optimal state and the output data of the accelerometer to be measured is stable, obtain the output data of the displacement monitoring instrument and the accelerometer to be measured in the same time period; Perform differential processing on the output data of the displacement monitoring instrument to obtain the translational acceleration signal of the vibration isolation platform, and further perform amplitude spectrum calculation on this signal as the theoretical output amplitude of the acceleration; Compare the amplitude spectrum of the theoretical acceleration with the measured acceleration of the accelerometer to be measured in the calibration direction to determine whether they match within the error range, and obtain the resolution test result of the accelerometer to be measured; 6. The method according to claim 5, characterized in that, This method further includes: By linearly fitting the amplitude spectra of the response accelerations of the accelerometer to be measured and the displacement monitoring instrument under different amplitude electromagnetic excitation signals, obtain the sensitivity calibration result of the accelerometer to be measured; 7. The method according to claim 5, characterized in that, This method further includes: By changing the frequency of the injected electromagnetic excitation signal, analyze the transfer function or low-frequency response characteristics of the accelerometer to be measured; 8. An accelerometer performance testing system, characterized in that, Comprising: The accelerometer performance test device, memory, and processor according to any one of claims 1 to 4; The memory is used to store computer programs and execution instructions; The processor is configured to execute the computer-executable instructions, and when the computer program runs on the processor, cause the method according to any one of claims 5 to 7 to be executed.

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