A test platform and method for dynamic characteristics of an accelerometer

Abstract

This invention discloses a dynamic characteristic testing platform and method for an accelerometer. The platform includes a signal generator, an exciter, a standard accelerometer, an accelerometer under test (AUT), a data acquisition module, and a test analysis software module. The signal generator outputs sinusoidal excitation signals of different frequencies; the exciter generates mechanical vibration based on these signals; the standard accelerometer is mounted on the exciter and outputs a standard acceleration signal; the AUT is rigidly connected to the standard accelerometer and outputs a corresponding voltage signal; the data acquisition module simultaneously acquires both signals; the test analysis software module performs FFT frequency domain transformation and numerical calculations on the acquired signals to obtain the acceleration value and output voltage amplitude, calculates the sensitivity and decibel value of the AUT at different frequencies, and plots the amplitude-frequency characteristic curve to determine the operating bandwidth. This invention requires no closed-loop control, has a simple structure, is easy to operate, and is suitable for experimental teaching.

Description

Technical Field

[0001] This invention relates to the field of acceleration sensor detection technology, and in particular to an acceleration sensor dynamic characteristic testing platform and method. Background Technology

[0002] Dynamic characteristics are an important indicator for evaluating a sensor's ability to respond quickly to changes in the measured parameter. To ensure reliable operation and accurate measurement, the dynamic characteristics of the sensor need to be tested and calibrated regularly during the manufacturing and use of the sensor.

[0003] Currently, there are two main types of frequency response calibration methods for accelerometers: the sinusoidal vibration comparison method and the impact excitation method. The sinusoidal vibration comparison method, which yields a complete frequency response curve for the sensor, is more widely used. However, both of these calibration methods typically require a closed-loop vibration control system and a known constant acceleration value. Closed-loop vibration control systems are complex and expensive, making them difficult to deploy and use extensively in university experimental teaching.

[0004] If an open-loop excitation system is used for testing, the following technical challenges exist: when the excitation frequency changes, the mechanical response of the coupling system consisting of the exciter and the accelerometer under test will change with the frequency, causing the acceleration amplitude output by the exciter to inevitably drift, thus failing to guarantee the constancy of the acceleration amplitude during the test and seriously affecting the accuracy of the test results.

[0005] Therefore, how to accurately test the dynamic characteristics of acceleration sensors without relying on expensive closed-loop vibration control equipment has become a technical problem that urgently needs to be solved in this field.

[0006] The information disclosed in the background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] To address the aforementioned shortcomings and deficiencies in existing dynamic characteristic testing techniques for accelerometers, this invention proposes a novel approach: abandoning the strict requirement of maintaining a constant input acceleration amplitude during testing, instead employing a dual-sensor synchronous measurement method at each frequency sweep point. This involves acquiring the input acceleration signal value and the output signal value of the accelerometer under test separately, calculating the ratio of these two values ​​to determine the sensor's sensitivity, converting it to decibels, and finally plotting the amplitude-frequency response curve to determine the sensor's operating bandwidth. The testing platform and method provided by this invention offer significant advantages such as simple structure, convenient operation, and accurate and reliable test results.

[0008] To achieve the above objectives, the present invention adopts the following technical solution.

[0009] An accelerometer dynamic characteristics testing platform includes:

[0010] A signal generator is used to output sinusoidal excitation signals of different frequencies and amplitudes in an adjustable manner.

[0011] A vibrator, connected to the signal generator, is used to generate mechanical vibration based on the sinusoidal excitation signal;

[0012] A standard accelerometer is mounted on the exciter to measure the mechanical vibration and output a first acceleration signal;

[0013] The acceleration sensor under test is rigidly connected to the standard acceleration sensor and is used to sense the same mechanical vibration and output a second signal.

[0014] The data acquisition module is connected to the standard accelerometer and the accelerometer under test, respectively, and is used to synchronously acquire the first acceleration signal and the second signal;

[0015] The test analysis software module, connected to the data acquisition module, is used to perform numerical calculations and FFT frequency domain analysis based on the first acceleration signal and the second signal to obtain the acceleration value of the standard acceleration sensor and the output signal value of the acceleration sensor under test.

[0016] In the aforementioned accelerometer dynamic characteristic testing platform, the data acquisition module acquires the first acceleration signal and the second signal at different frequencies and amplitudes.

[0017] In the aforementioned accelerometer dynamic characteristic testing platform, the signal generator includes an amplitude adjustment knob and a corresponding amplitude range display window for adjusting the output signal, a frequency adjustment knob and a corresponding frequency display window for adjusting the output signal frequency, and a signal output interface for connecting to the exciter.

[0018] In the aforementioned accelerometer dynamic characteristic testing platform, the exciter is used to drive the standard accelerometer and the accelerometer under test to generate reciprocating displacement in the vertical direction, and the displacement signal is a sine signal.

[0019] In the aforementioned accelerometer dynamic characteristic testing platform, the standard accelerometer is an accelerometer with known sensitivity and that has been calibrated.

[0020] In the aforementioned accelerometer dynamic characteristic testing platform, the operating bandwidth frequency range of the standard accelerometer completely covers and exceeds the operating bandwidth frequency range of the accelerometer under test.

[0021] The test method based on the above-mentioned accelerometer dynamic characteristic test platform includes the following steps:

[0022] The signal generator outputs sinusoidal excitation signals of different frequencies;

[0023] The exciter generates mechanical vibration based on the sinusoidal excitation signal;

[0024] The mechanical vibration is measured by the standard accelerometer, and a first acceleration signal is output.

[0025] The same mechanical vibration is sensed by the test acceleration sensor, which is rigidly connected to the standard acceleration sensor, and a second signal is output;

[0026] The data acquisition module synchronously acquires the first acceleration signal and the second signal;

[0027] The test and analysis software module performs numerical calculations and FFT frequency domain analysis on the collected signals to obtain the acceleration value of the standard accelerometer and the output signal value of the accelerometer under test.

[0028] In the aforementioned testing method, the sensitivity of the accelerometer under test is measured at different frequencies. (unit: The acceleration measured by the standard accelerometer. (Unit: g) and the amplitude of the output signal measured by the accelerometer under test (unit: The relationship between them is as follows:

[0029] ,

[0030] The normalized sensitivity, i.e., decibel value, of the accelerometer under test at different frequencies. The calculation formula (unit: dB) is as follows:

[0031] .

[0032] In the formula, For the accelerometer under test at frequency Sensitivity at the lower level For its reference frequency Sensitivity at that level.

[0033] In the aforementioned test method

[0034] By adjusting the amplitude and frequency of the sinusoidal excitation signal output by the signal generator, the corresponding acceleration value is measured by the standard accelerometer.

[0035] Measure the output signal values ​​of the accelerometer under test at different frequencies, and apply the relationship described above:

[0036]

[0037] and the calculation formula:

[0038]

[0039] Calculate the sensitivity and decibel value of the accelerometer under test at each frequency point.

[0040] In the aforementioned test method

[0041] Plot the amplitude-frequency response curve based on the decibel values ​​of the accelerometer under test at each frequency point, and determine the frequency range of the operating bandwidth of the accelerometer under test based on the amplitude-frequency response curve.

[0042] In the aforementioned test method

[0043] A sinusoidal excitation signal is input and its frequency is adjusted. A frequency sweep test is performed within a certain acceleration intensity range. The actual acceleration value corresponding to the sinusoidal excitation signal is measured by the standard accelerometer, and the corresponding output signal value is collected by the accelerometer under test.

[0044] Based on the acceleration value measured by the standard accelerometer and the output signal value measured by the accelerometer under test, the sensitivity of the accelerometer under test at each frequency is calculated according to the above relationship and calculation formula. and decibel value ; with frequency as the horizontal axis and decibel value as the horizontal axis Plot the amplitude-frequency response curve of the accelerometer under test with the normalized sensitivity (i.e., dB) as the vertical axis.

[0045] In the aforementioned test method

[0046] According to general regulations in the field of acoustic and electrical instruments, when The frequency corresponding to ±3 dB is the cutoff frequency of the sensor's operating bandwidth, and the frequency range covered by the ±3 dB tolerance band is the effective operating bandwidth of the sensor.

[0047] This invention meets the basic requirements of the mechanical vibration method frequency response test in the GJB 1037A-2004 series standards, eliminating the need for expensive closed-loop control equipment while accurately acquiring the amplitude-frequency characteristics of the sensor. This invention provides a stable and reliable testing platform and method for the dynamic characteristics of accelerometers. Compared with existing technologies, the beneficial effects of this invention are as follows:

[0048] This invention overcomes the strict requirement of constant acceleration input in traditional testing methods. It employs a dual-sensor synchronous measurement approach at each sweep frequency point, acquiring the input and output acceleration signal values ​​separately. The sensitivity of the tested accelerometer is calculated by the ratio of these two values ​​and further converted to decibels, thus generating a complete and accurate amplitude-frequency characteristic curve. This method effectively avoids systematic errors introduced by fluctuations in the exciter output amplitude with frequency, significantly improving testing accuracy. The platform features a simple operation process and intuitive data processing, facilitating rapid determination of the dynamic characteristics of accelerometers. This invention significantly reduces the performance requirements of the excitation equipment, eliminating the need for an expensive constant acceleration standard vibration table, effectively saving on experimental equipment investment. Due to its low cost, simple structure, convenient operation, and reliable test results, this invention enables the widespread implementation and popularization of accelerometer dynamic characteristic testing experiments in university experimental teaching, possessing significant practical value for improving the teaching quality of sensor-related courses.

[0049] The description provided is merely an overview of the technical solution of this invention. In order to make the technical means of this invention clearer and more understandable, so that those skilled in the art can implement it according to the contents of the specification, and to make the described and other objects, features and advantages of this invention more obvious and understandable, specific embodiments of this invention are described below. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the platform structure according to an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of parameter settings for the standard accelerometer acquisition channel AI1-01 within the test and analysis software module in one embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of the parameter settings for the AI1-02 acquisition channel of the acceleration sensor under test in the test analysis software module in one embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of the spectrum obtained by FFT transformation of the acquired signal in one embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the amplitude-frequency response curve plotted based on the decibel value of the acceleration sensor under test in one embodiment of the present invention.

[0055] The present invention will be further explained and described below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0056] The following will be combined with the appendix Figures 1 to 5The present invention will be described in detail below. Although key embodiments of the invention are shown in the accompanying drawings, it should be understood that the drawings are provided only to facilitate a better understanding of the invention and should not be construed as limiting the scope of protection of the invention.

[0057] Example 1

[0058] like Figure 1 As shown, an accelerometer dynamic characteristic testing platform includes,

[0059] A signal generator, connected to the exciter via a signal line, is used to output sinusoidal excitation signals of different frequencies to the exciter. The frequency adjustment knob on the signal generator allows setting sinusoidal signals of different frequencies within the range of 0~10kHz; the amplitude of the sinusoidal signal can be adjusted via a vibration acceleration amplitude knob, and its magnitude can be displayed in real time within a certain range through a corresponding amplitude display window.

[0060] The exciter, connected to the signal generator, is used to generate vertical mechanical vibration based on the sinusoidal excitation signal.

[0061] A standard accelerometer is mounted on the vibration table of the exciter to measure the mechanical vibration and output a first acceleration signal.

[0062] The accelerometer under test is rigidly connected to the standard accelerometer and is used to sense mechanical vibrations that are exactly the same as those of the standard accelerometer and output a second signal.

[0063] The data acquisition module is connected to the standard accelerometer and the accelerometer under test, respectively, and is used to synchronously acquire the first acceleration signal and the second signal; the data acquisition module also provides a 5V operating voltage to the accelerometer under test.

[0064] The test and analysis software module, connected to the data acquisition module, is used to acquire and process the first acceleration signal and the second signal. By setting the parameters of each acquisition channel in the test and analysis software module: channel AI1-01 is used to acquire the standard accelerometer sensor signal, and its sensitivity is set to the factory calibration value of the standard accelerometer sensor, such as... Figure 2 As shown; channel AI1-02 is used to acquire the signal from the accelerometer under test, and its sensitivity is set to 1, as shown. Figure 3 As shown. Through numerical calculation and FFT transformation, the actual acceleration value measured by the standard accelerometer and the voltage signal value output by the accelerometer under test can be obtained respectively.

[0065] In a preferred embodiment, the data acquisition module acquires the first acceleration signal and the second signal at different frequencies and amplitudes.

[0066] In a preferred embodiment, the signal generator includes an output signal amplitude adjustment knob and a corresponding amplitude range display window, an output signal frequency adjustment knob and a corresponding frequency display window, and a signal output interface for connection to the exciter.

[0067] In a preferred embodiment, the exciter is used to drive the standard accelerometer and the accelerometer under test to generate a reciprocating displacement in the vertical direction, and the displacement signal is a sinusoidal signal.

[0068] In a preferred embodiment, the standard accelerometer is an accelerometer with known sensitivity and that has been calibrated.

[0069] In a preferred embodiment, the operating bandwidth frequency range of the standard accelerometer completely covers and exceeds the operating bandwidth frequency range of the accelerometer under test.

[0070] The test method based on the above-mentioned accelerometer dynamic characteristic test platform includes the following steps:

[0071] The signal generator outputs sinusoidal excitation signals of different frequencies;

[0072] The exciter generates mechanical vibration based on the sinusoidal excitation signal;

[0073] The mechanical vibration is measured by the standard accelerometer, and a first acceleration signal is output.

[0074] The same mechanical vibration is sensed by the test acceleration sensor, which is rigidly connected to the standard acceleration sensor, and a second signal is output;

[0075] The data acquisition module synchronously acquires the first acceleration signal and the second signal;

[0076] The test analysis software module performs FFT frequency domain analysis and numerical calculations on the collected signals to obtain the actual acceleration value measured by the standard accelerometer and the output signal value of the accelerometer under test.

[0077] In a preferred embodiment, the sensitivity of the accelerometer under test at different frequencies is... (unit: The acceleration measured by the standard accelerometer. (Unit: g) and the amplitude of the output signal measured by the accelerometer under test (unit: The relationship between them is as follows:

[0078] ,

[0079] The decibel values ​​of the accelerometer under test at different frequencies The calculation formula (unit: dB) is as follows:

[0080] .

[0081] In the formula, For the accelerometer under test at frequency Sensitivity at the lower level For its reference frequency Sensitivity at that level.

[0082] In a preferred embodiment, by adjusting the frequency of the sinusoidal excitation signal output by the signal generator, the standard accelerometer measures the corresponding actual acceleration value, and the test accelerometer measures the corresponding output signal value, thereby calculating the operating bandwidth frequency range of the test accelerometer.

[0083] In a preferred embodiment, the operating bandwidth frequency range of the accelerometer under test is determined based on the amplitude-frequency characteristic curve.

[0084] In one specific embodiment, the test is performed according to the following steps: First, a signal generator, an exciter, an accelerometer, a data acquisition module, and a computer are connected in sequence to ensure that the signal output by the signal generator can correctly drive the exciter and enable the accelerometer to be in normal working condition; then, the sampling frequency and other acquisition parameters are set through the data acquisition module and its test analysis software module; finally, acceleration signals at different frequencies and amplitudes are acquired to ensure that the acquired data covers the expected operating range of the accelerometer under test.

[0085] In one specific embodiment, a test analysis software module with data analysis capabilities is used to analyze the experimental data, including operations such as spectrum analysis and data reading, to determine the main characteristic parameters (such as sensitivity) of the accelerometer under test; the corresponding decibel value is calculated based on the sensitivity at each frequency point, and then the amplitude-frequency characteristic curve is plotted; the vibration characteristics of the accelerometer under test are analyzed based on the amplitude-frequency characteristic curve, thereby obtaining its operating bandwidth and resonant frequency.

[0086] In one specific embodiment, the amplitude knob on the signal generator is used to adjust the amplitude of the output sinusoidal signal, thereby ensuring that the acceleration amplitude generated by the exciter is within the range of the accelerometer under test, thus guaranteeing the accuracy and effectiveness of the measurement. The exciter is used to drive the accelerometer to generate a reciprocating displacement in the vertical direction. The displacement signal is a sinusoidal signal, therefore the acceleration signal measured by the sensor is also a sinusoidal signal. The standard accelerometer is an accelerometer with known sensitivity and has been calibrated. It is rigidly connected to the accelerometer under test and is used to measure the actual input acceleration signal in order to calculate the dynamic sensitivity of the accelerometer under test. The data acquisition module provides a 5V operating voltage to the accelerometer under test and is connected to both the standard accelerometer and the accelerometer under test to achieve synchronous signal acquisition. The test analysis software module performs FFT frequency domain analysis on the output signals of the standard accelerometer and the accelerometer under test to obtain the acceleration value measured by the standard accelerometer and the output signal value of the accelerometer under test.

[0087] In one specific embodiment, the frequency sweep test is performed according to the following steps: Figure 1 As shown, connect the signal generator, exciter, accelerometer, data acquisition module, and computer in sequence to ensure that the signal output from the signal generator can correctly drive the exciter. Mount both the standard accelerometer and the accelerometer under test on the vibration table of the exciter, ensuring a rigid connection between them. The signal generator provides the exciter with a series of sinusoidal excitation signals at different vibration frequencies, the intensity of which corresponds to the displacement amplitude of the exciter. The type and frequency of the excitation signals can be adjusted manually or automatically. This embodiment uses manual input of sinusoidal signals of different frequencies. Since the AI1-01 channel of the test analysis software module is used to acquire the standard accelerometer signal, the channel parameter settings are as follows: Figure 2 As shown, the actual sensitivity of the standard accelerometer is set, so the corresponding standard acceleration value can be directly read through the test and analysis software module; at the same time, since the AI1-02 channel is used to acquire the signal from the accelerometer under test, the channel parameters are set as follows. Figure 3 As shown, the sensitivity of the accelerometer under test is set to 1, so the amplitude of the output voltage signal of the accelerometer under test can be read through the test analysis software module. Figure 4 As shown, the acceleration value of the standard accelerometer and the output signal amplitude of the accelerometer under test can be clearly read from the spectrum obtained by FFT frequency domain analysis.

[0088] Rotate the frequency adjustment knob of the signal generator while simultaneously adjusting its amplitude knob to ensure the sensor's acceleration value remains within its effective operating range. Select a series of different frequency points within the 0-10kHz range, and measure and record the acceleration values ​​of the standard accelerometer and the output voltage values ​​of the accelerometer under test at the corresponding frequencies. Then, measure the acceleration values ​​of the standard accelerometer... (unit: and the output voltage of the accelerometer under test (unit: Enter the values ​​in Table 1. Based on the measurement data in Table 1 and the aforementioned formula, the sensitivity and decibel value of the accelerometer under test at each frequency point can be calculated. Plot the amplitude-frequency response curve based on the calculated decibel values, and finally determine the operating bandwidth frequency range of the accelerometer according to the ±3 dB criterion.

[0089] Table 1. Test data of the accelerometer at different frequencies

[0090] Sensitivity of the accelerometer under test at different frequencies (unit: Acceleration measured by a standard accelerometer (unit: ) and the output voltage measured by the accelerometer under test (unit: The relationship between them is as follows:

[0091]

[0092] According to relevant national standards for accelerometer calibration, the sensitivity K (160 Hz) at a frequency of 160 Hz is typically selected as the reference value. The sensitivity at each frequency is then normalized and expressed in decibels (dB). Therefore, the decibel values ​​of the accelerometer under test at different frequencies... The calculation formula (unit: dB) is as follows:

[0093]

[0094] In the formula, For the accelerometer under test at frequency Sensitivity at the lower level For its in Sensitivity at the reference frequency.

[0095] The data processing results can be referenced from the original data record table. If the tolerance zone is taken as... From the data in the table, we can see that the upper cutoff frequency of the accelerometer under test is approximately 2200Hz. To obtain a more accurate upper cutoff frequency, a series of frequency points around 2200Hz were selected for data acquisition and analysis again, and the results are shown in Table 2 below.

[0096] Table 2. Test data of the accelerometer in the 2000-2200Hz frequency range.

[0097] Plot the amplitude-frequency response curves based on the decibel values ​​of the accelerometer under test at different frequencies, such as... Figure 5 As shown. Through interpolation calculations, it can be obtained that when the frequency is approximately 2189 Hz, the decibel value of the accelerometer under test is approximately 3 dB, thus determining its upper cutoff frequency to be 2189 Hz. In summary, the dynamic operating frequency range of the accelerometer under test is 0–2189 Hz.

[0098] In summary, this invention breaks the bias of closed-loop testing and creatively proposes a dual-sensor synchronous measurement method at each sweep frequency point to directly measure the actual input acceleration value without maintaining it constant. This enables open-loop excitation systems to accurately test the dynamic characteristics of sensors and significantly reduces equipment costs.

[0099] Based on the above-described inventive concept of the present invention, in another embodiment, an accelerometer dynamic characteristic testing device includes:

[0100] The signal generator's output is electrically connected to the input of the exciter.

[0101] The vibrator has a standard acceleration sensor fixed on its vibration table.

[0102] The acceleration sensor to be tested is fixedly connected to the standard acceleration sensor via a rigid connector.

[0103] The data acquisition card has a first channel electrically connected to the output terminal of the standard accelerometer and a second channel electrically connected to the output terminal of the accelerometer under test.

[0104] A computer is communicatively connected to the output of the data acquisition card, and the computer stores test analysis programs.

[0105] In another embodiment, an accelerometer dynamic characteristic testing system includes:

[0106] An excitation signal source is used to apply excitations of different frequencies to the object under test;

[0107] A reference sensor is used to measure the physical quantity of the excitation and output a reference signal;

[0108] The sensor under test is coupled to the reference sensor and is used to sense the same excitation and output the signal under test.

[0109] A signal processor is configured to calculate the sensitivity of the sensor under test at different frequencies based on the reference signal and the signal under test, and to normalize the sensitivity relative to the sensitivity at a reference frequency to obtain a normalized sensitivity value, wherein the signal processor is further configured to output a curve of the normalized sensitivity value changing with time or frequency.

[0110] The above description is given for illustrative purposes only and is not intended to limit the embodiments of this application to the disclosed forms. Although several exemplary aspects and embodiments have been discussed above, those skilled in the art should understand that certain variations, modifications, alterations, additions, and sub-combinations can be made thereto without departing from the technical solution of this application, and all such variations, modifications, alterations, additions, and sub-combinations should fall within the protection scope defined by the claims of this application.

Claims

1. A dynamic characteristic testing platform for an accelerometer, characterized in that, include: A signal generator is used to output sinusoidal excitation signals of different frequencies and amplitudes in an adjustable manner. A vibrator, connected to the signal generator, generates mechanical vibration based on the sinusoidal excitation signal; A standard accelerometer is mounted on the exciter to measure the mechanical vibration and output a first acceleration signal; The acceleration sensor under test is rigidly connected to the standard acceleration sensor and is used to sense the same mechanical vibration and output a second signal. The data acquisition module is connected to the standard accelerometer and the accelerometer under test, respectively, and is used to synchronously acquire the first acceleration signal and the second signal; The test analysis software module, connected to the data acquisition module, is used to perform numerical calculations and FFT frequency domain analysis based on the first acceleration signal and the second signal to obtain the acceleration value of the standard acceleration sensor and the output signal value of the acceleration sensor under test.

2. The accelerometer dynamic characteristic testing platform as described in claim 1, characterized in that, Preferably, the data acquisition module is used to acquire the first acceleration signal and the second signal at different frequencies and amplitudes.

3. The accelerometer dynamic characteristic testing platform as described in claim 1, characterized in that, The signal generator includes an amplitude adjustment knob and a corresponding amplitude range display window for adjusting the output signal, a frequency adjustment knob and a corresponding frequency display window for adjusting the frequency of the output signal, and a signal output interface for connecting to the exciter.

4. The accelerometer dynamic characteristic testing platform as described in claim 1, characterized in that, The exciter is used to drive the standard accelerometer and the accelerometer under test to generate a reciprocating displacement in the vertical direction, and the displacement signal is a sinusoidal signal.

5. The accelerometer dynamic characteristic testing platform as described in claim 1, characterized in that, The standard accelerometer is an accelerometer with known sensitivity and that has been calibrated.

6. The accelerometer dynamic characteristic testing platform as described in claim 1, characterized in that, The operating bandwidth frequency range of the standard accelerometer completely covers and is greater than the operating bandwidth frequency range of the accelerometer under test.

7. A testing method based on the dynamic characteristic testing platform of an accelerometer according to any one of claims 1 to 6, characterized in that, Includes the following steps: The signal generator outputs sinusoidal excitation signals of different frequencies; The exciter generates mechanical vibration based on the sinusoidal excitation signal; The mechanical vibration is measured by the standard accelerometer, and a first acceleration signal is output. The same mechanical vibration is sensed by the test acceleration sensor, which is rigidly connected to the standard acceleration sensor, and a second signal is output; The data acquisition module synchronously acquires the first acceleration signal and the second signal; The test and analysis software module performs numerical calculations and FFT frequency domain analysis on the collected signals to obtain the acceleration value of the standard accelerometer and the output signal value of the accelerometer under test.

8. The test method as described in claim 7, characterized in that, The sensitivity of the acceleration sensor under test at different frequencies (unit: The acceleration measured by the standard accelerometer. (Unit: g) and the amplitude of the output signal measured by the accelerometer under test The relationship between (unit: mV) is as follows: ， The normalized sensitivity, i.e., decibel value, of the accelerometer under test at different frequencies. The calculation formula (unit: dB) is as follows: ， In the formula, For the accelerometer under test at frequency Sensitivity at the lower level For its reference frequency Sensitivity at that level.

9. The test method as described in claim 7, characterized in that, By adjusting the amplitude and frequency of the sinusoidal excitation signal output by the signal generator, the corresponding acceleration value is measured by the standard accelerometer. Measure the output signal values ​​of the accelerometer under test at different frequencies, and apply the relationship described above: ， and the calculation formula: ， Calculate the sensitivity and decibel value of the accelerometer under test at each frequency point.

10. The test method as described in claim 9, characterized in that, Plot the amplitude-frequency response curve based on the decibel values ​​of the accelerometer under test at each frequency point, and determine the frequency range of the operating bandwidth of the accelerometer under test based on the amplitude-frequency response curve.

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