A calibration method for an acceleration vibration sensor

Abstract

The application relates to a calibration method for an acceleration vibration sensor, which adopts a calibration device for the acceleration vibration sensor, and comprises the following steps: S1, fixing a vibration sensor to be calibrated on a horizontal slide table in a posture with an axis to be calibrated parallel to an excitation direction; S2, sampling interference signals output by a self-tracing grating interferometer and output voltage signals of the vibration sensor to be calibrated by using a signal acquisition and transmission device, and extracting an interference phase based on the interference signals; S3, determining a functional relationship between the interference phase signals and vibration displacement signals; and S4, calibrating the vibration sensor to be calibrated based on the functional relationship and the sampled output voltage signals of the vibration sensor to be calibrated. Compared with the prior art, the application has the advantages of high calibration precision, a measurement reference independent of wavelength, environmental interference resistance and the like, and solves the on-site vibration calibration tracing problem.

Description

Technical Field

[0001] This invention relates to the field of calibration technology for acceleration vibration sensors, and in particular to a calibration method for acceleration vibration sensors. Background Technology

[0002] With the exponential growth of human industrial scale, higher demands are being placed on the unmanned, intelligent, and precise operation of equipment. The material foundation for establishing more intelligent control technologies lies in more advanced condition monitoring sensors. Accelerometers, as acceleration sensing devices, have an extremely wide range of applications: they can be used in conjunction with gyroscopes for inertial positioning, providing navigation services for missiles, rockets, and submarines; they can be used for vibration monitoring of equipment and facilities, security alarms, and reducing safety hazards in large industrial facilities; they can be used in consumer electronics, motion recognition, health monitoring, and even in every smartphone. Therefore, accelerometers have permeated all aspects of our production and daily life, playing an increasingly important practical role.

[0003] Although modern accelerometers have achieved extremely high theoretical sensitivity, enabling precise measurement of acceleration, significant issues remain in their practical applications. Factors such as impacts, drops, temperature changes, and radiation can cause accelerometers to lose sensitivity or even suffer structural damage during use. Therefore, it is necessary to regularly check and calibrate the accelerometer's sensitivity to ensure measurement accuracy.

[0004] The currently accepted method for accelerometer vibration calibration is the absolute vibration calibration method based on laser interferometers. International standard ISO 16063-11 and Chinese standard GB / T 20485, both using this technology, employ this technique. Existing methods compare the absolute displacement of the accelerometer vibration measured by laser interferometry with the sensor signal output by the accelerometer to perform sensitivity testing. During sensitivity testing, the laser wavelength λ is a critical factor, and its accuracy has a decisive impact on the calibration precision. Changes in environmental conditions such as temperature, pressure, and humidity can cause wavelength disturbances, resulting in significant deviations in the calibration values. This is a major technical bottleneck in the implementation of absolute calibration in the field. In traditional absolute calibration, the accuracy of the laser itself also requires calibration using an iodine-stabilized laser interferometer. The corresponding displacement measurement traceability chain is: vibration displacement - helium-neon laser wavelength - iodine-stabilized laser interferometer wavelength. A longer traceability chain in the value transfer leads to a decrease in calibration precision. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology by providing a calibration method for acceleration vibration sensors with high calibration accuracy. This invention employs a self-traceable grating interferometer, which uses a self-traceable grating as the displacement measurement reference element. This allows the displacement measurement of the vibration system to be directly traced back to the self-traceable grating period - the chromium atom transition frequency. Compared with laser interferometers, the traceability chain is shorter, thus resulting in higher accuracy. At the same time, it uses a grating structure for displacement measurement, eliminating the problem of laser interferometers relying on laser wavelength as the reference and being greatly affected by the environment. This enables on-site traceable measurement. Therefore, this invention has the advantages of high calibration accuracy, wavelength-independent measurement reference, and resistance to environmental interference, solving the problem of on-site traceability in vibration calibration.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A calibration method for an acceleration vibration sensor, the method employing a calibration device for the acceleration vibration sensor, the device including a standard intermediate frequency excitation system, a vibration sensor to be calibrated, a self-traceable grating and fixing device, a self-traceable grating interferometer, signal acquisition and transmission equipment, and signal processing and display equipment, wherein the standard intermediate frequency excitation system is connected to a horizontal slide table;

[0008] The self-traceable grating and fixing device are mounted on the side of the horizontal slide table, so that the grating normal is perpendicular to the excitation direction. The self-traceable grating and fixing device includes the vibration table surface and the self-traceable grating disposed on the vibration table surface. The self-traceable grating interferometer includes a laser, an optical interference structure and a photodetector.

[0009] When the device is working, the laser generates linearly polarized light that is incident on the optical interference structure. After internal reshaping, the light passes through the self-traceable grating on the vibration table and then returns to the optical interference structure. The signal at this time is an interference signal. The interference signal is finally incident on the photodetector, and the photodetector outputs an interference voltage signal.

[0010] The method includes the following steps:

[0011] S1. Fix the vibration sensor to be calibrated on the horizontal slide with the axis to be calibrated parallel to the excitation direction to ensure that the standard intermediate frequency excitation system provides the input signal of the vibration sensor to be calibrated and the input signal of the self-traceable grating interferometer.

[0012] S2. Using signal acquisition and transmission equipment, the interference signal output by the self-traceable grating interferometer and the output voltage signal of the vibration sensor to be calibrated are sampled according to the Nyquist sampling theorem, and the interference phase is extracted based on the interference signal.

[0013] S3. Based on the structural principle of the interferometer, determine the functional relationship between the interference phase signal and the vibration displacement signal;

[0014] S4. Based on the functional relationship obtained in S3 and the sampled output voltage signal of the vibration sensor to be calibrated, the vibration sensor to be calibrated is calibrated.

[0015] Furthermore, the specific steps of S2 include:

[0016] S21. The interference signal is generated by four sequentially phase-differential signals. It consists of sinusoidal light intensity signals, and the four signals are converted into interference voltage signals based on a photodetector, from which two interference voltage signals are selected;

[0017] S22. High-frequency noise signals are removed from the interference voltage signal using a digital low-pass filter;

[0018] S23. Then, using the Heydemann ellipse correction method and the interference principle, the nonlinear effect of the filtered signal is calculated and corrected to obtain the standard orthogonal interference signal.

[0019] S24. Based on the phase expansion method, the interference signal phase is unwrapped from the standard orthogonal interference signal to obtain the interference phase.

[0020] Furthermore, in S4, the method for calibrating the vibration sensor to be calibrated is either the stripe counting method, the minimum point method, or the sine approximation method. The amplitude of the vibration sensor to be calibrated is calibrated using the stripe counting method or the minimum point method, while the amplitude and phase of the vibration sensor to be calibrated are calibrated using the sine approximation method.

[0021] Furthermore, when using the sine approximation method, the specific steps of S4 are as follows:

[0022] S41. Obtain the functional relationship of S3 and the sampled output voltage signal of the vibration sensor to be calibrated;

[0023] S42. The sinusoidal approximation method is used to fit the interference phase signal in the functional relationship and the output voltage signal of the vibration sensor to be calibrated. The DC bias is removed based on the filter to obtain the output voltage signal after removing the DC bias. The fitted vibration displacement signal is obtained according to the functional relationship and the interference phase signal after removing the DC bias. The second derivative of the fitted vibration displacement signal is obtained to obtain the excitation acceleration signal.

[0024] S43. Calculate the ratio of the fitted output voltage signal to the excitation acceleration signal. The ratio is used as a sensitivity characteristic to obtain the sensitivity amplitude and phase.

[0025] S44. Use signal processing and display equipment to save the sensitivity amplitude and phase, and calibrate the vibration sensor to be calibrated based on the sensitivity amplitude and phase.

[0026] Furthermore, the expression for the interference voltage signal is:

[0027]

[0028] Among them, u o The peak value of the interference signal. Let d be the initial phase of the interference signal, d be the period of the selected self-traceable grating, and u be the initial phase of the interference signal. out1 u out2 u out3 and u out4 The four phases are successively different. The sinusoidal light intensity signal, s(t) is the vibration displacement signal;

[0029] At this point, using the first and second interference voltage signals, the expression for the interference phase is:

[0030]

[0031] in, Let nπ be the interference phase, nπ be the phase compensation, and u' be the phase. out1 (t) represents the first signal of the standard orthogonal interference signal, u' out2 (t) is the second signal of the standard orthogonal interference signal.

[0032] Furthermore, the functional relationship between the interference phase signal and the vibration displacement signal is expressed as follows:

[0033]

[0034] Where s(t) is the vibration displacement signal, This is the interference phase.

[0035] Furthermore, the expression for the interference phase signal after removing the DC bias is:

[0036]

[0037] Where A1 and B1 are the parameters of the sine approximation method, f v Where i is the vibration frequency, and i is the timing index of the measurement signal;

[0038] The expression for the fitted vibration displacement signal, obtained based on the functional relationship and the interference phase signal after removing the DC bias, is as follows:

[0039]

[0040] Where A1 and B1 are the parameters of the sine approximation method, f v The frequency is the vibration frequency.

[0041] Furthermore, the expression for the excitation acceleration signal is:

[0042]

[0043] in, This is to provide an excitation acceleration signal.

[0044] Furthermore, the expression for the output voltage signal after removing the DC bias is:

[0045]

[0046] in, This is the output voltage signal after removing the DC bias.

[0047] Furthermore, the expression for the sensitivity characteristic is:

[0048]

[0049] in, To excite the acceleration signal, To remove the DC bias from the output voltage signal;

[0050] At this time, the sensitivity amplitude is Sensitivity phase is Where A1 and B1 are the parameters of the sine approximation method.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] (1) This invention employs a self-traceable grating interferometer. The laser of the self-traceable grating interferometer generates linearly polarized light that is incident on the optical interference structure. After internal reshaping, the light passes through the self-traceable grating on the vibration table, carrying displacement and phase information with the self-traceable grating period as the length reference, and then returns to the optical interference structure. Finally, the photodetector outputs an interference voltage signal. The vibration displacement-acceleration signal is calculated through the voltage signal, constructing a new traceability chain of "natural constant - self-traceable grating period - accelerometer vibration displacement". Compared with the existing traceability chain of "natural constant - iodine frequency-stabilized laser interferometer wavelength - helium-neon laser wavelength - accelerometer vibration displacement", this chain is greatly shortened, improving measurement accuracy and confidence. At the same time, the displacement measurement reference of this system is the grating period rather than the laser wavelength, which greatly improves the environmental anti-interference capability.

[0053] (2) This invention is stable and practical, and can realize the direct calibration of vibration sensors of different frequencies in the medium frequency range. The calibration process is simple and flexible, and can be used for the calibration of vibration sensors of different models and sizes.

[0054] (3) The present invention uses the sinusoidal approximation method to obtain the second derivative of the fitted vibration displacement signal to obtain the excitation acceleration signal, and then calculates the sensitivity based on the excitation acceleration signal for calibration, thereby improving the calibration accuracy. Attached Figure Description

[0055] Figure 1 This is a flowchart of the present invention;

[0056] Figure 2 This is a structural diagram of the device used in this invention;

[0057] Figure 3 This is a schematic diagram of the structure of the self-traceable grating and fixing device and the self-traceable grating interferometer of the present invention;

[0058] Figure 4 This is a flowchart of step 2 of the present invention;

[0059] Figure 5 This is a flowchart of step 4 of the present invention;

[0060] Figure 6 This is a diagram illustrating the fabrication process of the self-traceable grating of the present invention;

[0061] Figure 7 This is a diagram of a certain optical-voltage signal of the self-traceable grating interferometer of the present invention;

[0062] In the figure, there is a standard intermediate frequency excitation system 11, a vibration sensor to be calibrated 12, a self-traceable grating and fixing device 13, a self-traceable grating interferometer 14, a signal acquisition and transmission device 15, a signal processing and display device 16, a laser 31, an optical interference structure 32, a self-traceable grating 33, a vibration table surface 34, and a photodetector 35. Detailed Implementation

[0063] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0064] This invention proposes a calibration method for an acceleration vibration sensor, the flowchart of which is shown below. Figure 1 As shown.

[0065] This invention employs a calibration device for an acceleration vibration sensor, the structural diagram of which is shown below. Figure 2 As shown, the structural diagrams of the self-traceable grating and fixing device 13 and the self-traceable grating interferometer 14 are as follows. Figure 3 As shown. The device includes a standard intermediate frequency excitation system 11, a vibration sensor to be calibrated 12, a self-traceable grating and fixing device 13, a self-traceable grating interferometer 14, a signal acquisition and transmission device 15, and a signal processing and display device 16. The standard intermediate frequency excitation system 11 is connected to a horizontal slide.

[0066] The self-traceable grating and fixing device 13 are installed on the side of the horizontal slide table, so that the normal of the grating is perpendicular to the excitation direction. The self-traceable grating and fixing device 13 includes the vibration table surface 34 and the self-traceable grating 33 disposed on the vibration table surface 34. The self-traceable grating interferometer 14 includes a laser 31, an optical interference structure 32 and a photodetector 35.

[0067] When the device is working, the laser 31 generates linearly polarized light, which is incident on the optical interference structure 32 at a Littoral angle. After internal reshaping, the light passes through the self-traceable grating 33 on the vibration table 34 and then returns to the optical interference structure 32. The signal at this time is an interference signal. The interference signal is finally incident on the photodetector 35, and the photodetector 35 outputs an interference voltage signal.

[0068] The self-traceable grating interferometer 14 used in this invention performs absolute calibration of vibration sensors. It is used to measure the absolute displacement and phase of the vibration system, thereby achieving on-site traceability calibration. The displacement measurement principle of the self-traceable grating interferometer is based on the frequency shift effect of grating Doppler; therefore, its displacement measurement reference is the grating period d. Displacement measurement is achieved through laser interferometry using a zero-difference or heterodyne structure. The self-traceable grating 33 used in this invention is a deposited grating prepared by heating and sublimating a metal material to a gaseous state in a vacuum environment using laser focusing atomic deposition technology, and then extracting the metal atomic beam in a cascading manner. The types of metal atoms used can be Cr, Al, Fe, etc., and its grating period can be directly traced back to the natural constant of the atomic transition frequency. Figure 6 This diagram illustrates the fabrication process of the self-traceable grating 33 of the present invention. Taking a chromium atom self-traceable grating as an example, the fabrication process is described as follows: Generally, a crucible filled with chromium powder is heated to between 1550°C and 1650°C in a vacuum environment to achieve sublimation, forming a metal atom beam. Then, the chromium atom beam is collimated by a slit and laser cooling. The collimated Cr atom beam passes through a one-dimensional laser standing wave field orthogonal to it and is deposited onto a sample under the action of a dipole force to form a one-dimensional deposition grating structure. The wavelength of the one-dimensional laser standing wave field is 425.553 nm, corresponding to the resonant transition energy level of the Cr atom. The frequency of the one-dimensional laser standing wave field is tuned to a positive detuning position of +250MHz or a negative detuning position of -250MHz corresponding to the center frequency of the resonant energy level. Therefore, the pitch of the formed one-dimensional chromium (Cr) atom deposition grating is half the wavelength of the one-dimensional laser standing wave field used, which is 212.8nm. Since the one-dimensional chromium atom deposition grating prepared by laser focusing atom deposition technology requires the wavelength of the one-dimensional laser standing wave field to correspond to the wavelength of the atomic transition energy level in order to form a structure, and the wavelength of the formed one-dimensional chromium atom deposition grating is exactly equal to half the wavelength of the one-dimensional laser standing wave field, the one-dimensional chromium atom deposition grating is a self-traceable grating with metrological characteristics.

[0069] Using the above-described apparatus, the calibration method for an acceleration vibration sensor of the present invention includes the following steps:

[0070] S1. Fix the vibration sensor 12 to be calibrated on the horizontal slide table with the axis to be calibrated parallel to the excitation direction, so as to ensure that the standard intermediate frequency excitation system 11 provides the input signal of the vibration sensor 12 to be calibrated and the input signal of the self-traceable grating interferometer 14.

[0071] S2. Using signal acquisition and transmission equipment 15, the interference signal output by the self-traceable grating interferometer 14 and the output voltage signal of the vibration sensor 12 to be calibrated are sampled according to the Nyquist sampling theorem, and the interference phase is extracted based on the interference signal.

[0072] S3. Based on the structural principle of the interferometer, determine the functional relationship between the interference phase signal and the vibration displacement signal;

[0073] S4. Based on the functional relationship obtained in S3 and the sampled output voltage signal of the vibration sensor 12 to be calibrated, the vibration sensor 12 to be calibrated is calibrated.

[0074] In S2, the Nyquist sampling theorem requires that half of the system sampling frequency be higher than the highest frequency or bandwidth of the system signal to ensure that the true signal can be reconstructed without aliasing. Simultaneously, it ensures that the vibration sensor voltage signal and the interference voltage signal are sampled synchronously during the sampling process.

[0075] The flowchart for step 2 is as follows: Figure 4 As shown. The specific steps of S2 include:

[0076] S21. The interference signal is generated by four sequentially phase-differential signals. The signal consists of sinusoidal light intensity signals. Based on the photodetector 35, the four signals are converted into interference voltage signals, and two of the interference voltage signals are selected.

[0077] S22. High-frequency noise signals are removed from the interference voltage signal using a digital low-pass filter;

[0078] S23. Then, using the Heydemann ellipse correction method and the interference principle, the nonlinear effect of the filtered signal is calculated and corrected to obtain the standard orthogonal interference signal.

[0079] S24. Based on the phase expansion method, the interference signal phase is unwrapped from the standard orthogonal interference signal to obtain the interference phase.

[0080] In S21, the interference signal consists of four sequentially phase-differential signals. The sinusoidal light intensity signal, whose phase is modulated by vibration displacement, is linearly converted into a voltage signal by a photodetector, and can be described as follows:

[0081]

[0082] Where s(t) is the displacement signal, specifically:

[0083]

[0084] In the formula, u o The peak value of the interference signal. Let d be the initial phase of the interference signal, d be the period of the selected self-traceable grating, s0 be the peak value of the vibration displacement signal, and f be the initial phase of the interference signal. v and These represent the frequency and initial phase of the vibration displacement, respectively; the bandwidth of the system is... Where v p This represents the peak vibration velocity.

[0085] S22 and S23 perform error correction on the signal:

[0086] The acquired voltage signal is filtered by a digital low-pass filter to remove high-frequency noise. Then, the Heydemann method is used to calculate and correct the nonlinear effect of the signal based on the interference principle to obtain the standard orthogonal interference signal.

[0087] S24 performs phase unwrapping of standard orthogonal interference signals based on the phase expansion method:

[0088] Phase difference of any two adjacent items The phase of the orthogonal interference signals is calculated using the arctangent phase expansion algorithm. Let's take the first and second signals as examples:

[0089]

[0090] Among them, u' out1 (t) represents the first signal of the standard orthogonal interference signal, u' out2 (t) is the second signal of the standard orthogonal interference signal. The phase of the interference signal.

[0091] In equation (3), the arctangent is a periodic discontinuous function. To obtain the true phase, phase compensation nπ is introduced to avoid phase jumps, where n = 0, 1, 2...

[0092] After obtaining the optical phase, step S3 is executed. Due to the Doppler effect signal of the grating interferometer, the phase is directly linearly related to the displacement. The displacement information can be directly obtained through this transformation. The specific transformation relationship, that is, the functional relationship between the interference phase signal and the vibration displacement signal, is described as follows:

[0093]

[0094] Figure 7 The image shows a specific optical-voltage signal from a self-traceable grating interferometer. Taking a specific optical-voltage signal from a zero-difference chromium atom self-traceable grating interferometer as an example, the characteristics of its optical displacement signal are illustrated:

[0095] Figure 7 In the experiment, the vibration displacement amplitude was 1 mm and the frequency was 100 Hz. The period of the chromium atom self-traceability grating was 212.8 nm, which corresponds to a displacement signal period of 106.4 nm.

[0096] In S4, the method for calibrating the vibration sensor 12 to be calibrated is either the fringe counting method, the minimum point method, or the sinusoidal approximation method. The fringe counting method or the minimum point method is used to calibrate the amplitude of the vibration sensor 12, while the sinusoidal approximation method is used to calibrate both the amplitude and phase of the vibration sensor 12. The fringe counting method is generally used for sensitivity amplitude calibration in the frequency range of 1Hz-800Hz. It measures the accelerometer sensitivity amplitude by measuring the ratio of the interference fringe frequency to the vibration frequency using a counter or frequency comparator. Specifically, this is expressed as follows:

[0097]

[0098] Where u is the sensor output voltage, f f denoted as , f is the frequency of the interference fringes, f is the frequency of the vibration table, and d is the period of the selected self-traceable grating.

[0099] The minimum point method is generally applicable to sensitivity amplitude calibration in the frequency range of 800Hz-10kHz. It uses a bandpass filter with a center frequency equal to the vibration frequency to filter the signal, and then utilizes the zero-point property of the Bessel series to solve for the sensitivity amplitude. Specifically, it is expressed as:

[0100]

[0101] Where u is the sensor output voltage, f is the vibration table frequency, and x n d represents the corresponding Bessel series zero value, and d is the selected self-traceable grating period.

[0102] In addition to a distortion meter and a computing display device, the stripe counting method also requires a counter; the minimum point method also requires a spectrum analyzer and a zero-value detector; and the sine fitting method also requires a digital waveform recorder, etc.

[0103] When using the sine approximation method, the flowchart for step 4 is as follows: Figure 5 As shown. The specific steps of S4 are as follows:

[0104] S41. Obtain the functional relationship of S3 and the sampled output voltage signal of the vibration sensor 12 to be calibrated;

[0105] S42. The sinusoidal approximation method is used to fit the interference phase signal in the functional relationship and the output voltage signal of the vibration sensor 12 to be calibrated, and the DC bias is removed based on the filter to obtain the output voltage signal after removing the DC bias. The fitted vibration displacement signal is obtained according to the functional relationship and the interference phase signal after removing the DC bias. The second derivative of the fitted vibration displacement signal is calculated to obtain the excitation acceleration signal.

[0106] S43. Calculate the ratio of the fitted output voltage signal to the excitation acceleration signal. Use this ratio as a sensitivity characteristic to obtain the sensitivity amplitude and phase.

[0107] S44. The sensitivity amplitude and phase are stored using the signal processing and display device 16, and the vibration sensor 12 to be calibrated is calibrated based on the sensitivity amplitude and phase.

[0108] In S42, for the phase signal and the voltage signal u(t) output by the vibration sensor i The excitation displacement signal and the output voltage signal are fitted using a sinusoidal approximation method.

[0109]

[0110] u(t i )=A2cos(2πf v t i )-B2sin(2πf v t i )+C2t i +D2 (4)

[0111] In the formula f v Let be the vibration frequency; parameters A1, B1, C1, D1 and A2, B2, C2, D2 can be obtained by decomposing N equations. These parameters are approximated using the least squares method, specifically by solving for the minimum value I of the residual of the estimated function. min (A1, B1), that is, the minimum value is obtained by solving the multivariate function extremum through the matrix equation of its parameters. The expression for the minimum value is:

[0112]

[0113] For sensitivity at the calibration frequency, only the corresponding sinusoidal signal is needed. Therefore, the fitted signal needs to have the DC bias signal removed using a filter. After removing the bias voltage, the optical interference phase and sensor voltage signals are as follows:

[0114]

[0115]

[0116] The excitation displacement signal obtained by fitting using formula (4) is:

[0117]

[0118] The excitation acceleration signal can be obtained by taking the second derivative with respect to time using the displacement signal (9):

[0119]

[0120] The vibration sensor output voltage signal is:

[0121]

[0122] Where d is the grating period of the selected self-traceable grating; taking the chromium atom self-traceable grating as an example, d is 212.8 nm. In S43, the sensitivity characteristic S(t) is calculated. i This can be represented as:

[0123]

[0124] Therefore, its accelerometer sensor sensitivity amplitude is Sensitivity phase is Sensor frequency characteristics vary under different calibration frequency conditions.

[0125] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A calibration method for an acceleration vibration sensor, characterized in that, The method employs a calibration device for an acceleration vibration sensor, which includes a standard intermediate frequency excitation system (11), a vibration sensor to be calibrated (12), a self-traceable grating and fixing device (13), a self-traceable grating interferometer (14), a signal acquisition and transmission device (15), and a signal processing and display device (16). The standard intermediate frequency excitation system (11) is connected to a horizontal slide. The self-traceable grating and fixing device (13) are installed on the side of the horizontal slide table so that the grating normal is perpendicular to the excitation direction. The self-traceable grating and fixing device (13) includes the vibration table surface (34) and the self-traceable grating (33) provided on the vibration table surface (34). The self-traceable grating interferometer (14) includes a laser (31), an optical interference structure (32) and a photodetector (35). When the device is working, the laser (31) generates linearly polarized light that is incident on the optical interference structure (32). After internal re-normalization, the light passes through the self-tracing grating (33) on the vibration table (34) and then returns to the optical interference structure (32). The signal at this time is an interference signal. The interference signal is finally incident on the photodetector (35), and the photodetector (35) outputs an interference voltage signal. The method includes the following steps: S1. Fix the vibration sensor (12) to be calibrated on the horizontal slide with the axis to be calibrated parallel to the excitation direction, so as to ensure that the standard intermediate frequency excitation system (11) provides the input signal of the vibration sensor (12) to be calibrated and the input signal of the self-traceable grating interferometer (14). S2. Using signal acquisition and transmission equipment (15), the interference signal output by the self-traceable grating interferometer (14) and the output voltage signal of the vibration sensor (12) to be calibrated are sampled according to the Nyquist sampling theorem, and the interference phase is extracted based on the interference signal. S3. Based on the structural principle of the interferometer, determine the functional relationship between the interference phase signal and the vibration displacement signal; S4. Based on the functional relationship obtained in S3 and the sampled output voltage signal of the vibration sensor (12) to be calibrated, the vibration sensor (12) to be calibrated is calibrated. The specific steps of S2 include: S21. The interference signal is generated by four sequentially phase-differential signals. The four signals are composed of sinusoidal light intensity signals. Based on the photodetector (35), the four signals are converted into interference voltage signals, and two of the interference voltage signals that are mutually orthogonal are selected. S22. High-frequency noise signals are removed from the interference voltage signal using a digital low-pass filter; S23. Then, using the Heydemann ellipse correction method and the interference principle, the nonlinear effect of the filtered signal is calculated and corrected to obtain the standard orthogonal interference signal. S24. Based on the arctangent phase calculation and phase expansion method, the interference signal phase is unwrapped from the standard orthogonal interference signal to obtain the interference phase. The specific steps of S4 are as follows: S41. Obtain the functional relationship of S3 and the output voltage signal of the vibration sensor (12) to be calibrated sampled; S42. The sinusoidal approximation method is used to fit the interference phase signal in the functional relationship and the output voltage signal of the vibration sensor (12) to be calibrated. The DC bias is removed based on the filter to obtain the output voltage signal after removing the DC bias. The fitted vibration displacement signal is obtained according to the functional relationship and the interference phase signal after removing the DC bias. The second derivative of the fitted vibration displacement signal is obtained to obtain the excitation acceleration signal. S43. Calculate the ratio of the fitted output voltage signal to the excitation acceleration signal. The ratio is used as a sensitivity characteristic to obtain the sensitivity amplitude and phase. S44. Use signal processing and display equipment (16) to save the sensitivity amplitude and phase, and calibrate the vibration sensor (12) to be calibrated based on the sensitivity amplitude and phase; The expression for the interference voltage signal is: in, The peak value of the interference signal. The initial phase of the interference signal, For the selected self-traceable grating period, , , and The four phases are successively different. sinusoidal light intensity signal, This is a vibration displacement signal; At this point, using the first and second interference voltage signals, the expression for the interference phase is: in, For interference phase, For phase compensation, This is the first signal of the standard orthogonal interference signal. The second signal of the standard orthogonal interference signal, and the functional relationship between the interference phase signal and the vibration displacement signal are expressed as follows: in, This is a vibration displacement signal. This is the interference phase.

2. The calibration method for an acceleration vibration sensor according to claim 1, characterized in that, The amplitude and phase of the vibration sensor (12) to be calibrated are calibrated using the sinusoidal approximation method.

3. The calibration method for an acceleration vibration sensor according to claim 1, characterized in that, The expression for the interference phase signal after removing the DC bias is: in, and For the parameters of the sine approximation method, The vibration frequency, i For the timing label of the measurement signal; The expression for the fitted vibration displacement signal, obtained based on the functional relationship and the interference phase signal after removing the DC bias, is as follows: in, and For the parameters of the sine approximation method, The frequency is the vibration frequency.

4. The calibration method for an acceleration vibration sensor according to claim 3, characterized in that, The expression for the excitation acceleration signal is: in, This is to provide an excitation acceleration signal.

5. A calibration method for an acceleration vibration sensor according to claim 4, characterized in that, The expression for the output voltage signal after removing the DC bias is: in, This is the output voltage signal after removing the DC bias.

6. The calibration method for an acceleration vibration sensor according to claim 5, characterized in that, The expression for the sensitivity characteristic is: in, To excite the acceleration signal, To remove the DC bias from the output voltage signal; At this time, the sensitivity amplitude is Sensitivity phase is ,in, and These are the parameters for the sine approximation method.

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