A dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable

Abstract

The present invention discloses a dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable. This device relates to the technical field of displacement sensor calibration and includes the following steps: generating a multi-band standard sinusoidal displacement signal by driving a sinusoidal edge turntable to rotate based on a rotational speed generator; converting the rotational motion into periodic radial standard sinusoidal displacement changes through an approximate sinusoidal edge structure; adjusting the displacement amplitude by replacing sinusoidal edge turntables with different amplitudes based on the range, bandwidth, and probe size of the displacement sensor to be calibrated; and adjusting the sinusoidal displacement frequency by adjusting the speed parameter of the rotational speed generator; and calculating the sensor bandwidth based on the amplitude attenuation by fitting an amplitude-frequency characteristic curve using a least squares method with a preset attenuation threshold based on a dynamic sensitivity parameter. The device can generate medium- and high-frequency standard sinusoidal displacements, meeting the dynamic sensitivity and bandwidth calibration requirements of dynamic displacement sensors. The device has the characteristics of a wide range, a small size, and a low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of displacement sensor calibration, in particular to a dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable. Background Art

[0002] In the field of displacement sensor calibration technology, dynamic characteristic calibration of sensors, such as dynamic sensitivity, relies on a high-frequency vibration table. This table uses a standard sinusoidal displacement to calibrate the displacement sensor's dynamic sensitivity and bandwidth. However, existing technologies present several challenges, including the large size and high cost of the vibration table, and the fact that the standard sinusoidal displacement it can provide has a smaller amplitude at higher frequencies. Vibration tables struggle to generate standard sinusoidal displacements with high frequencies and amplitudes, making them incapable of meeting the dynamic sensitivity and bandwidth calibration requirements of medium- to high-frequency and large-amplitude displacement sensors. Consequently, the development of a new generation of dynamic sensitivity and bandwidth calibration devices for dynamic displacement sensors is urgently needed. Summary of the Invention

[0003] In view of the above existing problems, the present invention is proposed.

[0004] Therefore, the present invention provides a dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable, which solves the problem of generating high-frequency and large-amplitude standard displacement of traditional vibration tables, and realizes accurate calibration of the high-frequency dynamic sensitivity and bandwidth of the displacement sensor through a compact rotating structure.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The present invention provides a dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable, which includes: a signal generation module, which generates a multi-band standard sinusoidal displacement signal based on a rotation speed generating device driving the sinusoidal edge turntable to rotate, and converts the rotational motion into a periodic radial sinusoidal displacement change by adding a sinusoidal edge turntable; an amplitude-frequency adjustment module, which adjusts the displacement amplitude by replacing sinusoidal edge turntables with different amplitudes according to the demand for periodic radial sinusoidal displacement change, and adjusts the speed parameter of the rotation speed generating device to change the displacement frequency; a synchronous acquisition module, which deploys a standard dynamic displacement sensor and a sensor to be tested in parallel, and synchronously acquires the sinusoidal displacement signal and the output signal of the sensor to be tested; a feature extraction module, which locks the standard displacement characteristic frequency through an adaptive co-frequency extractor based on the synchronously acquired two-way signal, combines an envelope extraction algorithm and an adaptive frequency multiplication notch filter to separate the amplitude of the co-frequency component output by the sensor, and uses a polynomial regression model to perform time domain signal amplitude comparison to calculate the dynamic sensitivity parameter; and a bandwidth calibration module, which generates an amplitude-frequency characteristic curve based on the dynamic sensitivity parameter by determining a preset attenuation threshold, and calculates the sensor bandwidth by using a least squares fitting algorithm.

[0007] As a preferred solution of the dynamic displacement sensor calibration device based on the rotating sinusoidal edge turntable of the present invention, wherein: the sinusoidal edge turntable converts the rotational motion into periodic radial sinusoidal displacement changes, including the following steps:

[0008] A polar coordinate system is established with the center of the sinusoidal edge turntable as the origin. The arc length B of the center line of one sinusoidal cycle of the sinusoidal edge turntable is selected according to the diameter of the displacement sensor probe to be measured. c ;

[0009] According to the bandwidth w of the displacement sensor to be measured s and the maximum speed frequency f of the speed generator r Design the number of sinusoidal periods k of the turntable edge so that the number of sinusoidal periods k satisfies:

[0010] ,

[0011] The centerline radius R0 of the sinusoidal edge curve is calculated as:

[0012] ,

[0013] Calculate the radians corresponding to one sine cycle as:

[0014] ,

[0015] The amplitude A0 of the sinusoidal edge is selected according to the measuring range of the displacement sensor to be measured;

[0016] In the polar coordinate system, the turntable edge curve is designed as:

[0017] ,

[0018] in, The angle between the line connecting any point on the edge of the turntable and the center of the turntable and the Y axis of the rectangular coordinate system is in the range of .

[0019] Establish a rectangular coordinate system with the turntable edge curve and the turntable center as the origin (0,0), and convert the turntable edge curve into the rectangular coordinate system as follows:

[0020] ,

[0021] Where x and y are the coordinate values ​​of any point on the edge of the turntable.

[0022] As a preferred solution of the dynamic displacement sensor calibration device based on the rotating sinusoidal edge turntable of the present invention, wherein: the rotation speed generating device includes a switch to select automatic mode and manual mode;

[0023] In automatic mode, the frequency control command is generated according to the starting frequency, maximum frequency, calibration point interval, steady speed time and acceleration; in manual mode, the frequency is controlled by the target frequency and acceleration; the frequency control is combined with the sine edge turntable to automatically generate standard sinusoidal displacements in different frequency bands.

[0024] As a preferred solution of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable described in the present invention, the dual-path signal refers to the sinusoidal displacement signal output by the dynamic displacement sensor and the signal output by the displacement sensor to be measured, both of which are synchronously collected and respectively input into the adaptive same-frequency extractor.

[0025] As a preferred solution of the dynamic displacement sensor calibration device based on the rotating sinusoidal edge turntable of the present invention, wherein: the feature extraction module includes:

[0026] By calculating the sinusoidal frequency parameters corresponding to the current rotation frequency and the sinusoidal edge turntable in real time, the numerator and denominator of the adaptive frequency extractor transfer function are updated, and the parameters are dynamically adjusted to make the center frequency match the standard displacement characteristic frequency;

[0027] The envelope extraction algorithm is used to perform absolute value conversion, low-pass filtering and gain amplification processing;

[0028] By calculating the double frequency parameters of the sinusoidal frequency corresponding to the current rotating sinusoidal edge turntable in real time, the numerator and denominator of the adaptive frequency doubling notch filter transfer function are updated.

[0029] As a preferred solution of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable described in the present invention, the dynamic displacement sensor and the sensor to be measured adopt a coaxial installation structure, and the detection axes of the probes of the two are located in the same tangent direction of the sinusoidal edge turntable.

[0030] As a preferred solution of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable described in the present invention, the feature extraction module is integrated into the human-computer interaction interface, the turntable amplitude, number of sinusoidal cycles and speed parameters are input through the turntable parameter setting module, and the calibration results are visualized in real time in the data visualization area of ​​the interactive interface.

[0031] As a preferred solution of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable described in the present invention, the polynomial regression model generates dynamic sensitivity parameters by comparing the peak-to-peak values ​​of the synchronously processed standard signal and the signal to be measured.

[0032] As a preferred solution of the dynamic displacement sensor calibration device based on the rotating sinusoidal edge turntable of the present invention, the method for establishing the polynomial regression model includes the following steps:

[0033] Collect peak-to-peak value sample sets of the dynamic displacement sensor and the sensor to be tested at different speeds;

[0034] The input and output data are normalized to the same dimension through feature scaling, and the leave-one-out cross-validation method is used to determine the optimal polynomial order. The regularized least squares method is used to solve the regression coefficient matrix to save the benchmark parameters.

[0035] As a preferred solution of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to the present invention, the preset attenuation threshold refers to a critical point set according to the sensitivity attenuation characteristics of the amplitude-frequency characteristic curve.

[0036] The beneficial effects of the present invention are as follows: through the synergistic effect of the sinusoidal edge turntable and the speed generating device, high-frequency, large-amplitude standard sinusoidal displacement can be generated in a limited volume and cost, effectively solving the technical bottleneck of traditional vibration tables in generating high-frequency and large-amplitude displacements; an adaptive same-frequency extractor is used in combination with envelope extraction and multiplication frequency notch technology to achieve high-precision synchronous measurement and interference suppression of dynamic displacement signals, thereby ensuring the reliability of calibration data; the human-computer interaction interface developed based on LabVIEW integrates parameter configuration, real-time monitoring and curve analysis functions, significantly improving the calibration efficiency of sensor sensitivity and bandwidth; the overall device takes into account both calibration accuracy and engineering applicability through modular design, providing a standardized solution for the dynamic performance evaluation of displacement sensors in industrial scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 Schematic diagram of the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable.

[0039] Figure 2 This is the two-dimensional plane coordinate diagram of the sinusoidal edge turntable.

[0040] Figure 3 This is the relationship between the angle of the sinusoidal edge turntable and the dynamic standard displacement.

[0041] Figure 4 This is the time domain diagram of the dynamic standard displacement based on the sinusoidal edge turntable.

[0042] Figure 5 It is the core signal processing algorithm of the device.

[0043] Figure 6It is the host computer interface of this dynamic displacement sensor calibration device. DETAILED DESCRIPTION

[0044] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0045] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0046] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0047] Reference Figures 1 to 6 , is an embodiment of the present invention, which provides a dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable, comprising the following steps:

[0048] The present invention mainly consists of a standard dynamic displacement generating device, a signal acquisition and controller system, a core operation module, a human-computer interaction interface, and a position-adjustable mounting base.

[0049] Furthermore, the functional modules of the device of the present invention can be categorized as follows: the standard dynamic displacement generating device includes a signal generation module (a speed generator drives a sinusoidal edge turntable to generate a multi-band standard sinusoidal displacement signal) and the hardware portion of the amplitude-frequency adjustment module (adjusting the displacement amplitude and upper frequency limit by replacing a turntable with different amplitudes / periods); the signal acquisition and controller system corresponds to the synchronization acquisition module, deploying a dynamic displacement sensor installed in parallel with the sensor to be measured to achieve synchronous signal processing; the core computing module includes the feature extraction module (using an adaptive co-frequency extractor, an envelope extraction algorithm, and an adaptive multiplier notch filter to lock the standard displacement characteristic frequency and separate the co-frequency component amplitude) and the algorithm portion of the bandwidth calibration module (fitting the amplitude-frequency characteristic curve based on dynamic sensitivity parameters and calculating the bandwidth using a least squares algorithm); the human-computer interaction interface integrates software control of the amplitude-frequency adjustment module (setting speed parameters to change the standard sinusoidal displacement frequency), interactive display of the bandwidth calibration module (attenuation threshold determination, curve visualization), and real-time parameter monitoring functions; the position-adjustable mounting base serves as a hardware carrier, providing physical support for turntable installation, sensor fixation, and mechanical eccentricity, ensuring spatial accuracy and stability when the modules operate in coordination.

[0050] The standard dynamic displacement generator consists of a speed generator and a sinusoidal edge turntable. The speed generator provides a high-precision standard speed, and the speed value can be set via the host computer interface. The sinusoidal edge turntable is mounted on the speed generator's shaft, ensuring that its center axis is coaxial with the speed generator's rotor axis. A standard dynamic displacement generator typically features a set of sinusoidal edge turntables with varying amplitudes A0, centerline radii R0, and sinusoidal period numbers k. The appropriate turntable can be selected based on the estimated range, bandwidth, and sensor probe size of the displacement sensor to be calibrated. If necessary, a custom turntable can be customized based on the range, bandwidth, and other parameters of the displacement sensor to be calibrated.

[0051] When the displacement sensor to be measured is fixed to one side of the turntable and the probe direction points to the center of the turntable, the speed generating device cooperates with the sine edge turntable to generate a dynamic standard sinusoidal displacement relative to the probe of the sensor to be measured, and the frequency f of the generated standard sinusoidal displacement is the rotation frequency f of the speed generating device shaft. r The product of the number of sinusoidal periods k in one cycle of the sinusoidal edge turntable. The amplitude of the standard sinusoidal displacement is the amplitude A0 of the sinusoidal edge turntable. The frequency f can be generated by adjusting the speed of the speed generator through the human-computer interaction interface. sinmax =k×f rmax The standard sinusoidal displacement of any frequency below, where f rmax It is the maximum speed of the speed generating device.

[0052] The host computer interface is written by the software LabVIEW, and the input controls in the interface include the starting frequency f rstart , maximum rotation frequency f rmax , calibration point frequency switching interval d fr , Calibration point steady speed time T r And the acceleration a, the number of sinusoidal cycles k in one cycle of the sinusoidal edge turntable, the turntable amplitude A0, and the envelope extraction module low-pass cutoff frequency w c , adaptive same-frequency extraction coefficient k qf and adaptive frequency notch coefficient k nf ; The selection switch has a speed control mode selection switch; the signal value display module can display the standard sine frequency fsin, standard sine displacement peak-to-peak value A vpp , displacement sensor output peak-to-peak value V pp , displacement sensor output frequency f ssin , the sensitivity S of the displacement sensor to be measured, the bandwidth w of the displacement sensor to be measured s The test result image display module can display the amplitude-frequency characteristic curve of the displacement sensor to be tested, the standard sinusoidal displacement provided by the sinusoidal edge turntable and the time domain diagram of the displacement signal output by the displacement sensor to be tested, the standard displacement spectrum and the displacement spectrum diagram of the displacement sensor to be tested.

[0053] Among them, the core operation module is mainly used to obtain the current frequency f r The standard sinusoidal displacement and the sinusoidal displacement signal of the displacement sensor to be calibrated are obtained, and the sensitivity of the displacement sensor to be measured is calculated; finally, the amplitude-frequency characteristic curve of the displacement sensor to be measured is plotted and the bandwidth is calculated. The core algorithm is mainly composed of an adaptive same-frequency extractor, an envelope extraction module and an adaptive frequency multiplication notch filter cascade. The same-frequency and frequency multiplication mentioned here refer to the frequency relative to the standard sinusoidal displacement. This module is a universal signal processing module in the present invention, which can be used to process signals from standard displacement sensors as well as signals from displacement sensors to be measured. The device can provide a standard sinusoidal signal through a rotating sinusoidal edge turntable, but since the turntable may be affected by installation eccentricity, unbalanced vibration and circuit noise interference, it will produce a frequency different from f sin =k×f r In order to extract the standard sinusoidal displacement signal, the signal is first passed through the adaptive frequency extractor, which can extract the signal with a frequency of f. sin The sine signal is extracted; then the signal is passed through the envelope extraction module, which first takes the absolute value of the signal and then filters out the high-frequency signal to extract the sine signal amplitude envelope; considering that the absolute value transformation will introduce a larger frequency f dsin =2×k×f r The frequency multiplication interference is not easy to be filtered out, so the envelope signal is finally input into the adaptive frequency multiplication notch filter, and the frequency introduced in the envelope module is f dsin The disturbance signal is filtered out.

[0054] like Figure 1 As shown, the dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable mainly includes a sinusoidal edge turntable, a standard displacement sensor, a speed generator, a controller, and a human-machine interface. The device's workflow involves selecting appropriate sinusoidal edge turntable and speed generator parameters based on the estimated sensitivity, range, and bandwidth of the displacement sensor to be measured. These parameters include the sinusoidal edge turntable amplitude A0, the number of sinusoidal cycles k per revolution of the sinusoidal edge turntable, and the maximum speed f of the speed generator. rmax ; Then place the displacement sensor to be measured and the standard displacement sensor in parallel on one side of the sinusoidal edge turntable so that the physical displacement of the rotor measured by them is the same; then start the speed generating device through the human-machine interface and controller to make the rotation frequency f rmax The output of the displacement sensor to be tested and the output of the standard displacement sensor are read simultaneously; the sensitivity of the displacement sensor to be tested at each speed calibration point is then calculated, and finally the amplitude-frequency characteristic curve of the displacement sensor to be tested is drawn and the bandwidth is calculated.

[0055] like Figure 2As shown, the sinusoidal edge turntable can generate a sinusoidal displacement relative to the sensor probe to be measured when rotating at a constant speed (for example, the amplitude A0 of the sinusoidal edge is selected to be within a range of approximately one-third to two-thirds of the range of the displacement sensor to be measured). A polar coordinate system and a plane rectangular coordinate system are established with the center of the turntable as the origin O. The turntable edge curve can be expressed in the polar coordinate system as follows:

[0056] ,

[0057] in, is the radian corresponding to one sine cycle, and , R0 is the centerline radius of the turntable edge curve, and A0 is the amplitude of the sine curve.

[0058] Specifically, a polar coordinate system is established with the center of the sinusoidal edge turntable as the origin, and the centerline arc length B of one sinusoidal cycle of the sinusoidal edge turntable is selected according to the diameter of the displacement sensor probe to be measured (such as a multiple of ten times the diameter). c ;

[0059] According to the bandwidth w of the displacement sensor to be measured s and the maximum speed frequency f of the speed generator r Design the number of sinusoidal periods k of the turntable edge so that the number of sinusoidal periods k satisfies:

[0060] ,

[0061] The centerline radius R0 of the sinusoidal edge curve is calculated as:

[0062] ,

[0063] Calculate the radians corresponding to one sine cycle as:

[0064] ,

[0065] The amplitude A0 of the sinusoidal edge is selected according to the measuring range of the displacement sensor to be measured;

[0066] Preferably, by designing the turntable edge curve, the radial displacement between the sinusoidal edge and the sensor probe to be measured can be changed to a standard sine when the sinusoidal edge rotates.

[0067] In the rectangular coordinate system with the center of the turntable as the origin (0,0), it can be expressed as:

[0068] ,

[0069] Among them, x and y are the coordinate values ​​of any point on the edge of the turntable. The angle between the line connecting the point (x, y) on the edge of the turntable and the center of the turntable and the Y axis of the rectangular coordinate system is within the range of ; B c is the arc length of a circle with radius R0 corresponding to one sinusoidal cycle of the sinusoidal edge turntable, When processing the sinusoidal edge turntable, the coordinates of each point of the sinusoidal edge turntable can be obtained according to the above method.

[0070] like Figure 3 As shown, when the turntable edge is processed Figure 2 When the sine curve is shown, the displacement sensor probe to be measured is installed on the Y axis at a suitable position away from the edge of the turntable and points to the origin O. When the turntable rotates at a constant speed for one circle, the sinusoidal edge turntable will generate k standard dynamic sinusoidal displacements with an amplitude of A0. The sinusoidal displacement is proportional to the angle The relationship is described as:

[0071] ,

[0072] like Figure 4 As shown, when the turntable rotates at a frequency f r During rotation, due to , dynamic distance ρ between the turntable edge and the sensor probe dy(t) for:

[0073] ,

[0074] is the initial phase. The dynamic distance between the dynamic displacement sensor probe and the turntable edge will show a standard sinusoidal displacement. The amplitude of the sinusoidal displacement A0 can be adjusted by designing and installing a turntable with different sinusoidal edges, and the frequency of the sinusoidal displacement can be adjusted by adjusting the rotational frequency f of the speed generator. r The adjustment is achieved by adjusting the number of sinusoidal periods k of the designed and installed sinusoidal edge turntable in one circle.

[0075] like Figure 5 As shown in the figure, the core operation module of the dynamic displacement sensor calibration device based on the rotating sine edge turntable is mainly composed of an adaptive frequency extractor, an envelope extraction module and an adaptive frequency multiplication notch filter cascade. When the displacement sensor signal to be measured or the standard displacement sensor signal is collected and input into the core operation module, X in Indicates that when the number of approximate sines in one cycle of the sinusoidal edge turntable is k, the rotation frequency of the shaft is f r When , the transfer function and amplitude-frequency characteristic function of the adaptive same-frequency extractor are:

[0076] ,

[0077] ,

[0078] in, It can be seen that the displacement sensor signal to be measured or the standard displacement sensor signal X can be extracted by the adaptive frequency extractor. in The frequency in The components of are extracted and the output is c(t). Figure 5 The envelope extraction module is composed of absolute value conversion, low-pass filtering and amplification modules. After c(t) passes through the envelope extraction module, the envelope can be extracted and recorded as d(t). However, due to the existence of the absolute value conversion module, d(t) is mixed with the frequency of The interference signal is filtered out by the adaptive frequency multiplication notch filter, where the transfer function and amplitude-frequency characteristic curve of the adaptive frequency multiplication notch filter are as follows:

[0079] ,

[0080] ,

[0081] It can be seen that after d(t) passes through the adaptive notch module, the frequency that can be filtered out is The interference signal makes the final output X out In order to obtain an envelope curve with less interference, it is convenient to read the amplitude of the same frequency component of the displacement signal.

[0082] Furthermore, the peak-to-peak values ​​of the standard signal and the signal to be measured are compared using a polynomial regression model: first, the peak-to-peak values ​​of the synchronized signal are aligned in time series and the clock deviation is compensated. Then, a quadratic regression equation containing nonlinear error terms is established, and the dynamic sensitivity parameters are solved using the least squares method. Finally, the reliability is verified through residual analysis.

[0083] It should also be noted that the establishment of the polynomial regression model is based on the peak-to-peak sample set of the dynamic displacement sensor and the sensor to be tested at different speeds collected from historical calibration data. The input and output data are normalized to the same dimension through feature scaling, and the leave-one-out cross-validation method is used to determine the optimal polynomial order to avoid overfitting. The regularized least squares method is used to solve the regression coefficient matrix to save the benchmark parameters for the calculation of dynamic sensitivity parameters; during the real-time calibration process, the online residual monitoring dynamically adjusts the model weights to ensure that the optimal fitting accuracy is maintained in different speed ranges.

[0084] like Figure 6 As shown, the host computer operation interface of the dynamic displacement sensor calibration device based on the rotating sine edge turntable is written in LabVIEW software. The interface mainly includes a speed generator control module, a turntable parameter setting module, a signal processing parameter setting module, a signal value display module, and a test result image display module. Among them, the speed generator control module can select automatic mode and manual mode by the speed control mode selection switch. In automatic mode, the starting speed frequency f needs to be entered in the input control. rstart , maximum rotation frequency frmax , calibration point frequency switching interval d fr , Calibration point steady speed time T r And the specific value of acceleration a, then click on the motor to start, the speed generator will increase the speed from zero frequency to the starting frequency f with acceleration a. rstart Then continue to increase the speed with acceleration a, and the frequency interval d of the calibration point fr Gradually increase the speed to the next calibration frequency point and maintain a steady speed at the frequency position T r seconds, and then repeat the process of speed increase and speed stabilization until the speed reaches the highest frequency f rmax At each calibration point, the steady speed T r Within seconds, the program will automatically execute the data acquisition and analysis calculation process, and partially display it in the parameter display module and image display module, such as the standard sine frequency f sin , Standard sinusoidal displacement peak-to-peak value A vpp , displacement sensor output peak-to-peak value V pp , displacement sensor output frequency f ssin , the sensitivity S of the displacement sensor to be measured, the bandwidth w of the displacement sensor to be measured s When the motor stop button is clicked, the speed generator will decelerate to zero at an acceleration of -a. At the same time, the program will automatically summarize the amplitudes at the calibration points and fit the amplitude-frequency characteristic curve of the displacement sensor to be tested, which is displayed in the image display module. The bandwidth is calibrated using a preset attenuation threshold (such as -3dB): the frequency points where the sensitivity attenuates to the threshold are scanned on the fitting curve, the cutoff frequency is calculated by linear interpolation, and a multi-threshold verification report is generated.

[0085] It should be noted that the method for obtaining the preset attenuation threshold is: according to the technical specifications or performance requirements of the sensor application scenario, the bandwidth calibration module program defaults to an attenuation decibel value (such as -3dB) corresponding to a frequency that is the bandwidth of the displacement sensor, and normalizes the relative attenuation ratio of the amplitude-frequency characteristic curve (such as -3dB corresponds to an amplitude attenuation of 70.7%). At the same time, it supports importing external configuration files to read customized thresholds for specific application scenarios. All set parameters are stored in the configuration database for subsequent calibration process calls. When the user does not actively set it, the -3dB recommended by the International Electrotechnical Commission is used as the benchmark threshold by default to ensure the industry universality of the measurement results.

[0086] Furthermore, the application method of the preset attenuation threshold is as follows: based on the normalized amplitude-frequency characteristic curve, a critical value of sensitivity attenuation is set as a judgment basis, and the curve data points are scanned forward along the frequency axis. When the first interval with an amplitude lower than the preset attenuation threshold is detected, the frequency and amplitude data of the adjacent sampling points on both sides of the interval are extracted, and the precise intersection frequency of the curve and the threshold line is calculated by linear interpolation as a candidate cutoff frequency value. The candidate value is subjected to harmonic interference analysis and confidence verification. If the signal-to-noise ratio condition is met, it is confirmed as an effective bandwidth. Finally, the threshold line, cutoff frequency mark and bandwidth verification report are synchronously displayed in the interactive interface to complete the quantitative calibration of the sensor's dynamic performance.

[0087] When manual mode is selected, the target frequency f can be set. rset and acceleration b. When the motor is clicked to start, the speed generator will stabilize the shaft frequency to the target frequency. When the frequency needs to be adjusted, just enter the target value in the target frequency input control. In the speed generator control module, the current frequency display control can display the frequency at the current moment. The frequency refresh time control can control the time interval for refreshing the value of the current frequency display control. The turntable parameter setting module needs to be set according to the actual parameters of the sinusoidal edge turntable currently installed on the shaft of the speed generator. The parameters that need to be set before each experiment are the number of sinusoidal periods k of the sinusoidal edge turntable in one circle and the turntable amplitude A0. The signal processing parameter setting module can set the low-pass cutoff frequency w of the envelope extraction module. c , adaptive same-frequency extraction coefficient k qf and adaptive frequency notch coefficient k nf The signal value display module can display the standard sinusoidal displacement frequency value f sin , Standard sinusoidal displacement peak-to-peak value A vpp , displacement sensor output peak-to-peak value V pp , displacement sensor output sinusoidal frequency f ssin , and the displacement sensor sensitivity S under test. These parameters are automatically refreshed when the rotational frequency reaches the calibration point in automatic rotation control mode, or after the rotational frequency stabilizes at the target frequency in manual mode. Clicking the refresh button on the signal display module will execute background program calculations and refresh the data. The previous set of data is stored for later estimation of the sensor bandwidth under test and plotting the displacement sensor's amplitude-frequency characteristic curve. After the test is completed, a least-squares fitting algorithm is used to construct the amplitude-frequency characteristic curve based on the dynamic sensitivity data at each calibration point. The sensitivity parameters are normalized and then fitted to a second-order transfer function model. Through optimization iterations, the error between the curve and the measured data is minimized, providing a benchmark for bandwidth determination.

[0088] Furthermore, by clicking the Start Calculation button, the background program automatically calculates the bandwidth of the displacement sensor under test and plots its amplitude-frequency characteristic curve. In the test result graphical display module, the Standard Displacement and Displacement Sensor under Test graph displays the standard sinusoidal displacement provided by the rotating sinusoidal edge turntable and the displacement signal output by the displacement sensor under test. The Standard Displacement and Displacement Spectrum graph displays the frequency spectrum of the standard displacement and the frequency spectrum of the displacement output by the displacement sensor under test.

[0089] In summary, the present invention can generate high-frequency, large-amplitude standard sinusoidal displacements in a limited volume and cost through the synergistic effect of the sinusoidal edge turntable and the speed generating device, effectively solving the technical bottleneck of traditional vibration tables in the generation of high-frequency and large-amplitude displacements; the adaptive same-frequency extractor is combined with envelope extraction and multiplication frequency notch technology to achieve high-precision synchronous measurement and interference suppression of dynamic displacement signals, ensuring the reliability of calibration data; the human-computer interaction interface developed based on LabVIEW integrates parameter configuration, real-time monitoring and curve analysis functions, significantly improving the calibration efficiency of sensor sensitivity and bandwidth; the overall device takes into account both calibration accuracy and engineering applicability through modular design, providing a standardized solution for the dynamic performance evaluation of displacement sensors in industrial scenarios.

[0090] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable, characterized by: include, The signal generation module drives the sine edge turntable to rotate based on the speed generator to generate a multi-band standard sine displacement signal. The sine edge turntable converts the rotational motion into periodic radial sinusoidal displacement changes; The amplitude-frequency adjustment module adjusts the displacement amplitude by replacing the sine edge turntable with different amplitudes according to the periodic radial sinusoidal displacement change requirements, and adjusts the speed parameters of the speed generator to change the displacement frequency; Synchronous acquisition module, deploys a standard dynamic displacement sensor and installs it in parallel with the displacement sensor to be measured, synchronously acquires the sinusoidal displacement signal and the output signal of the displacement sensor to be measured; The feature extraction module uses an adaptive co-frequency extractor to lock the standard displacement characteristic frequency based on the synchronously processed dual-channel signals. It then uses an envelope extraction algorithm to separate the amplitude of the co-frequency component of the sensor output. It then uses an adaptive multiplier notch filter to suppress the multiplier component. A polynomial regression model is then used to perform peak-to-peak comparison of the time domain signals to calculate the dynamic sensitivity parameters. The bandwidth calibration module, based on the dynamic sensitivity parameter, fits the amplitude-frequency characteristic curve by presetting the attenuation threshold and using the least squares method, and calculates the sensor bandwidth according to the amplitude attenuation; The sinusoidal edge turntable converts the rotational motion into periodic radial sinusoidal displacement changes, including the following steps: Establish a polar coordinate system with the center of the sinusoidal edge turntable as the origin, and select the centerline arc length B of one sinusoidal cycle of the sinusoidal edge turntable according to the diameter of the displacement sensor probe to be measured. c ; According to the bandwidth w of the displacement sensor to be measured s and the maximum speed frequency f of the speed generator r Design the number of sinusoidal periods k of the turntable edge so that the number of sinusoidal periods k satisfies: , Calculate the radius R0 of the center line of the sinusoidal edge curve and the arc corresponding to one sinusoidal period; The amplitude A0 of the sinusoidal edge is selected according to the measuring range of the displacement sensor to be measured; In the polar coordinate system, the turntable edge curve is designed as: , in, The angle between the line connecting any point on the edge of the turntable and the center of the turntable and the Y axis of the rectangular coordinate system is in the range of ; Establish a rectangular coordinate system with the turntable edge curve and the turntable center as the origin (0,0), and convert the turntable edge curve into the rectangular coordinate system as follows: , Where x and y are the coordinate values ​​of any point on the edge of the turntable.

2. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The speed generating device includes a switch to select automatic mode and manual mode; In automatic mode, the frequency control command is generated according to the starting frequency, maximum frequency, calibration point interval, steady speed time and acceleration; in manual mode, the frequency is controlled by the target frequency and acceleration; the frequency control is combined with the sine edge turntable to automatically generate standard sinusoidal displacements in different frequency bands.

3. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 2, characterized in that: The dual-path signal refers to the sinusoidal displacement signal output by the standard dynamic displacement sensor and the signal output by the displacement sensor to be measured, both of which are synchronously collected and respectively input into the adaptive frequency-matching extractor.

4. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The feature extraction module includes: By calculating the sinusoidal frequency parameters corresponding to the current rotation frequency and the sinusoidal edge turntable in real time, the numerator and denominator of the adaptive frequency extractor transfer function are updated, and the parameters are dynamically adjusted to make the center frequency match the standard displacement characteristic frequency; The envelope extraction algorithm is used to perform absolute value conversion, low-pass filtering and gain amplification processing; By calculating the double frequency parameters of the sinusoidal frequency corresponding to the current rotating sinusoidal edge turntable in real time, the numerator and denominator of the adaptive frequency doubling notch filter transfer function are updated.

5. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The standard dynamic displacement sensor and the displacement sensor to be measured adopt a coaxial installation structure, and the detection axes of the probes of the two are located in the same tangent direction of the sinusoidal edge turntable.

6. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The feature extraction module is integrated into the human-computer interaction interface. The turntable amplitude, number of sine cycles and speed parameters are input through the turntable parameter setting module, and the calibration results are visualized in real time in the data visualization area of ​​the interaction interface.

7. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The polynomial regression model generates a dynamic sensitivity parameter by comparing the peak-to-peak values ​​of the synchronously processed standard signal and the signal to be measured.

8. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 7, characterized in that: The method of establishing a polynomial regression model includes the following steps: Collect peak-to-peak value sample sets of the standard dynamic displacement sensor and the displacement sensor to be tested at different speeds; The input and output data are normalized to the same dimension through feature scaling, and the leave-one-out cross-validation method is used to determine the optimal polynomial order. The regularized least squares method is used to solve the regression coefficient matrix to save the benchmark parameters.

9. The dynamic displacement sensor calibration device based on a rotating sinusoidal edge turntable according to claim 1, characterized in that: The preset attenuation threshold refers to a critical point set according to the sensitivity attenuation characteristics of the amplitude-frequency characteristic curve.

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