Underwater pressure sensor dynamic calibration system and method using three-axis vibration synchronous control

Abstract

The invention discloses an underwater pressure sensor dynamic calibration system and method using three-axis vibration synchronous control. According to a three-axis vibration table displacement control algorithm, a three-degree-of-freedom vibration table is accurately controlled to realize vibration environment simulation in the X-axis, Y-axis and Z-axis orthogonal directions, and millisecond-level synchronous control of vibration of the vibration table and laser emission is realized in cooperation with an FPGA controller; the key technical problems of vibration environment accurate reproduction, cavitation bubble generation position stability control, multi-device simultaneous control and the like in the dynamic calibration process are effectively solved. Therefore, the calibration result of the underwater pressure sensor in the in-situ vibration environment is ensured to be accurate and reliable, and a reliable technical scheme is provided for sensor calibration in a complex vibration environment.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic pressure calibration of underwater pressure sensors, and in particular to a dynamic calibration system and method that combines a vibration simulation pressure sensor with an underwater in-situ working environment, for realizing precise in-situ calibration of underwater pressure sensors under vibration conditions. Background Art

[0002] In the field of strategic equipment research and development, there is a widespread demand for microsecond-level dynamic pressure measurement in liquid environments. Examples include research on ship explosion and shock resistance, aircraft engine operating status monitoring, and dynamic monitoring of high-frequency water pressure fluctuations in deep-sea submersibles. The accuracy of underwater microsecond-level dynamic pressure measurement is directly related to equipment performance evaluation and safety and reliability. In these scenarios, pressure sensors must achieve high-precision capture of dynamic signals in complex liquid vibration environments. To ensure accurate and reliable dynamic pressure measurement results, regular dynamic calibration of pressure sensors is required.

[0003] However, existing underwater dynamic pressure sensor calibration techniques have significant limitations and are difficult to meet practical needs. Traditional underwater dynamic calibration techniques often use a reference material method, using the shock wave generated by explosive detonations as the excitation source. However, this method has inherent drawbacks such as poor repeatability and low safety. Furthermore, the vibration and noise caused by the explosion can severely interfere with sensor signal acquisition, significantly reducing calibration accuracy.

[0004] The researchers proposed an improved solution, combining a high-pressure liquid environment simulation chamber with laser-induced cavitation bubbles to generate pressure waves as a dynamic calibration excitation source. The shock waves during the cavitation collapse process were then used to simulate the in-situ environmental pressure. However, the application scenarios of microsecond underwater dynamic pressure sensors are often accompanied by vibration. Existing dynamic calibration technology does not consider the underwater vibration environment that the sensor may encounter in actual application, and cannot reproduce the vibration excitation in the sensor's in-situ working environment. Therefore, its calibration results cannot truly reflect the sensor's performance in the in-situ environment. Furthermore, the calibration system relies on a single trigger mechanism and static positioning method, making it difficult to maintain the stability of the cavitation bubble generation position under vibration conditions. Summary of the Invention

[0005] To address the in-situ calibration challenges of pressure sensors operating in underwater vibration environments, this paper proposes a dynamic calibration system and method for underwater pressure sensors based on synchronous vibration control. This system uses a three-axis vibration table to simulate the dynamic environment, and an FPGA controller to synchronize the vibration table's motion with the laser emission timing, achieving high-precision calibration in this vibrating environment.

[0006] The method for dynamic calibration of an underwater pressure sensor using three-axis vibration synchronous control in the present invention comprises the following steps:

[0007] Set the trigger phase angles of the three vibration directions of the triaxial vibration table, and the motor drives the vibration table to move to the corresponding position, which is recorded as the laser trigger position;

[0008] After the vibration table reaches the laser trigger position, it controls the pulsed laser to emit laser light, and uses an ultra-high-speed camera to capture the morphological changes of the cavitation bubble generation and collapse process to obtain the cavitation bubble position information;

[0009] According to the cavitation bubble position information, adjust the beam expansion and focusing optical path module so that the cavitation bubble center is located on the line connecting the standard pressure sensor and the pressure sensing surface center of the pressure sensor to be calibrated; then adjust the sensor clamping and fine-tuning device so that the cavitation bubble center is at the midpoint of the line to complete the cavitation bubble position calibration;

[0010] Configure the amplitude parameters, frequency parameters, and acceleration parameters of the three orthogonal axes of the vibration table to simulate the vibration environment in the orthogonal directions of X, Y, and Z axes;

[0011] The FPGA controller generates drive signals based on set parameters and implements independent control of three orthogonal vibration directions based on the displacement control algorithm of the three-axis vibration table, causing the vibration table to perform sinusoidal motion in the three directions according to preset parameters. An internal counter accurately monitors the real-time phase angle of each vibration axis of the vibration table to determine whether the laser trigger position has been reached.

[0012] When the vibration table moves periodically to the laser trigger position, the digital delay trigger sends a trigger signal to the pulse laser. The laser enters the water tank through the beam expansion and focusing optical path module, and is precisely focused on the midpoint of the line connecting the pressure-sensitive surfaces of the two sensors to generate cavitation, thus achieving high-precision synchronous control of the vibration table movement and laser emission.

[0013] The pressure wave generated by the collapse of the cavitation bubble acts on the pressure-sensing surface of the pressure sensor, and the sensor signal acquisition device collects the output signals of the standard sensor and the sensor to be calibrated;

[0014] Perform Fourier transform on the collected output signals of the two sensors, compare the frequency response characteristics of the two sensors, and complete the calibration of the pressure sensor to be calibrated.

[0015] The present invention uses a dynamic calibration device for underwater pressure sensors using three-axis vibration synchronous control, which is used to implement the above calibration method, and includes:

[0016] An electronically controlled three-axis vibration table is used to simulate the in-situ vibration environment of the pressure sensor and provide the vibration conditions required for dynamic calibration;

[0017] An ultra-high-speed camera, in conjunction with the electronically controlled three-axis vibration table, is used to collect morphological changes during the generation and collapse of cavitation bubbles to obtain cavitation bubble position information;

[0018] An environmental chamber, accommodating the sensor and providing a liquid environment for the calibration process;

[0019] a pulsed laser, used in conjunction with the electrically controlled three-axis vibration table and the ultra-high-speed camera, to emit laser light to generate cavitation bubbles;

[0020] A sensor signal acquisition device, connected to the sensor in the environmental chamber, for acquiring output signals of the standard pressure sensor and the pressure sensor to be calibrated;

[0021] A digital delay trigger is connected to the pulse laser and the electrically controlled three-axis vibration table, and is used to send a trigger signal to the pulse laser when the vibration table reaches the laser trigger position;

[0022] A beam expansion and focusing optical path module, which cooperates with the pulsed laser and the ultra-high-speed camera to adjust the focus position of the laser to ensure that cavitation bubbles are generated at the midpoint of the line connecting the pressure-sensitive surface of the standard pressure sensor and the pressure sensor to be calibrated;

[0023] Sensor clamping and fine-tuning device, used to install and adjust the position of the standard pressure sensor and the pressure sensor to be calibrated;

[0024] The FPGA controller is connected to the electronically controlled three-axis vibration table and the digital delay trigger, and is used to generate a drive signal and realize high-precision synchronous control of the vibration table movement and laser emission, as well as realize independent control of the three orthogonal vibration directions of X, Y, and Z according to the displacement control algorithm of the three-axis vibration table.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) A cavitation bubble position calibration method for an adjustable laser trigger position is proposed. By adjusting the two sensor clamping and fine-tuning devices and the adjustable beam expansion and focusing optical path module respectively, the cavitation generation position and the sensor position are adjusted respectively, ensuring that the cavitation center can be accurately positioned at the geometric midpoint of the line connecting the pressure-sensitive surfaces of the two sensors each time the vibration table periodically moves to the laser trigger position.

[0027] (2) The millisecond-level synchronous control of the vibration table movement and laser emission is achieved through the FPGA controller to ensure that the relative position of the cavitation bubble generation position and the sensor pressure sensing surface is constant under the vibration environment, eliminating vibration interference.

[0028] (3) According to the displacement control algorithm of the three-axis vibration table, the three-degree-of-freedom vibration table can be precisely controlled to realize the vibration environment simulation in the three orthogonal directions of X / Y / Z. It supports the setting of continuously adjustable vibration frequency from 50Hz to 1KHz, variable amplitude from 1mm to 5mm and acceleration range from 1.5m / s² to 2m / s² in three directions, thereby realizing the precise in-situ calibration of pressure sensors in the in-situ underwater vibration environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the dynamic calibration system of the liquid phase pressure sensor for vibration synchronization control;

[0030] Figure 2 Schematic diagram of the sensor clamping and fine-tuning device;

[0031] Figure 3 Schematic diagram of the corresponding vibration table position and control equation;

[0032] Figure 4 This is the workflow diagram of the dynamic calibration system. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0034] To address the calibration requirements of underwater pressure sensors under complex vibration conditions, the present invention proposes an innovative in-situ calibration system and method. Based on a three-axis vibration table displacement control algorithm, the present invention precisely controls a three-degree-of-freedom vibration table to simulate the vibration environment in the orthogonal directions of the X, Y, and Z axes. In conjunction with an FPGA controller, millisecond-level synchronization control of the vibration table and laser emission is achieved. This effectively addresses key technical challenges during dynamic calibration, such as accurate reproduction of the vibration environment, positional stability control of cavitation bubble generation, and simultaneous control of multiple devices. This ensures the accuracy and reliability of the calibration results of underwater pressure sensors in in-situ vibration environments, providing a reliable technical solution for sensor calibration in complex vibration environments.

[0035] like Figure 1 As shown, this embodiment proposes a dynamic calibration system for a liquid-phase pressure sensor based on synchronous vibration control. The calibration system includes an electrically controlled triaxial vibration table 1, an ultrahigh-speed camera 2, an environmental chamber 3, a pulsed laser 7, a sensor signal acquisition device 8, a digital delay trigger 9, a computer 10, and a beam expansion and focusing optical module. The beam expansion and focusing optical module includes a focusing lens 4, an electrically controlled translation stage 5, and a beam expander 6. The system also includes an inner collet 11, an outer collet 12, and a fixing screw 13.

[0036] An electrically controlled triaxial vibration table 1 is used to simulate the in-situ vibration environment of the pressure sensor and provide the vibration conditions required for dynamic calibration;

[0037] An ultra-high-speed camera, in conjunction with the electronically controlled three-axis vibration table 1, is used to collect morphological changes during the generation and collapse of cavitation bubbles to obtain cavitation bubble position information;

[0038] Environmental chamber, which houses the sensor and provides a liquid environment for the calibration process;

[0039] A pulse laser, in conjunction with the electrically controlled three-axis vibration table 1 and the ultra-high-speed camera 2, is used to emit laser light to generate cavitation bubbles;

[0040] A sensor signal acquisition device, connected to the sensor in the environmental chamber 3, for acquiring output signals of the standard pressure sensor and the pressure sensor to be calibrated;

[0041] A digital delay trigger, connected to the pulse laser 7 and the electronically controlled three-axis vibration table 1, for sending a trigger signal to the pulse laser when the vibration table reaches the laser trigger position;

[0042] A computer 10 is connected to the electronically controlled triaxial vibration table 1, the ultra-high-speed camera 2, the sensor signal acquisition device 8 and the digital delay trigger 9, and is used to control the entire calibration process and process the collected signals;

[0043] The beam expansion and focusing optical path module cooperates with the pulse laser 7 and the ultra-high-speed camera 2 to adjust the focus position of the laser to ensure that cavitation bubbles are generated at the midpoint of the line connecting the pressure-sensitive surface of the standard pressure sensor and the pressure sensor to be calibrated;

[0044] The sensor clamping and fine-tuning device includes an inner collet 11, an outer collet 12 and a fixing screw 13, which is used to install and adjust the position of the standard pressure sensor and the pressure sensor to be calibrated. Figure 2 ;

[0045] The FPGA controller is connected to the electronically controlled three-axis vibration table 1 and the digital delay trigger 9, and is used to generate a drive signal and realize high-precision synchronous control of the vibration table movement and laser emission, as well as to realize independent control of the three orthogonal vibration directions of X, Y, and Z according to the displacement control algorithm of the three-axis vibration table.

[0046] The electrically controlled three-axis vibration table in this application can simulate the in-situ vibration environment of the pressure sensor. First, the cavitation bubble position information is observed through an ultra-high-speed camera, and then the cavitation bubble position is calibrated by adjusting the beam expansion and focusing optical path module and the sensor clamping and fine-tuning device. Then, the FPGA controller is used to drive the vibration table and synchronously trigger the laser so that the laser is precisely focused on the midpoint of the line connecting the pressure-sensitive surfaces of the two sensors. Then, the sensor signal acquisition device is used to collect and compare the output signals of the standard sensor and the sensor to be calibrated to complete the dynamic performance calibration of the sensor to be calibrated.

[0047] like Figure 4 As shown, Figure 4 FIG. 1 is a schematic diagram of a method for dynamic calibration of a pressure sensor in an underwater vibration environment according to an embodiment of the present invention, comprising the following steps:

[0048] First, the center position of the cavitation bubble needs to be calibrated before formal calibration. The calibration steps are as follows:

[0049] Step S1: Install the standard pressure sensor and the pressure sensor to be calibrated and preliminarily adjust their positions.

[0050] Specifically, first, the standard pressure sensor and the pressure sensor to be calibrated are symmetrically installed in the two sensor clamping and fine-tuning devices in the water tank. The two sensor clamping and fine-tuning devices are welded to the upper and lower surfaces of the tank respectively and are distributed along the same straight line. Therefore, the sensors installed in the device are also distributed along the same straight line following the collet. The sensor clamping and fine-tuning device adopts a double-layer collet structure. The three-dimensional schematic, side view and cross-sectional view of the sensor clamping and fine-tuning device are as follows: Figure 2 After the sensor is installed, it is clamped by the inner collet 11. By loosening the two fixing screws 13 on the outer collet 12, the inner collet 11 can be released, thereby adjusting the vertical degree of freedom of the sensor.

[0051] Step S2: Set the trigger phase angles θ1 (X-axis), θ2 (Y-axis), and θ3 (Z-axis) of the three vibration directions of the vibration table. After setting, the motor drives the vibration table to move to the corresponding position, and this position is recorded as the laser trigger position.

[0052] Specifically, the water tank is connected to a three-axis vibration table via slide rails, which drive the vibration table to achieve independent vibration control in three orthogonal directions: X, Y, and Z. The trigger phase angles θ1 (X-axis), θ2 (Y-axis), and θ3 (Z-axis) can be set separately for each of the three vibration directions. Once set, the motor drives the vibration table to the corresponding position, which is recorded as the laser trigger position.

[0053] Step S3: After the vibration table moves to the laser trigger position, the pulse laser is controlled to emit laser light, and the ultra-high-speed camera is used to obtain accurate cavitation bubble position information.

[0054] Specifically, when the vibration table is in the laser trigger position, the pulse laser is controlled to emit laser, and cavitation is formed between the two sensors after passing through the beam expansion and focusing optical path module. The high-speed camera combined with the shadow imaging method can be used to monitor the morphological changes of the cavitation bubble generation and collapse process in real time, and obtain accurate cavitation bubble position information.

[0055] Step S4: According to the obtained cavitation bubble position information, the beam expansion and focusing optical path module and the sensor clamping and fine-tuning device are adjusted to complete the calibration of the cavitation bubble center position.

[0056] Specifically, the electrically controlled displacement stage below the beam expanding and focusing optical path module is adjusted according to the accurate cavitation bubble position information obtained above, and the position of the generated cavitation bubble is adjusted by changing the positions of the beam expanding mirror and the focusing mirror, so that the center of the cavitation bubble is located on the line connecting the center of the pressure-sensitive surface of the standard pressure sensor and the pressure sensor to be calibrated.

[0057] Then, the position of the sensor is adjusted by adjusting the sensor clamping and fine-tuning device to ensure that the center of the generated cavitation bubble is located at the midpoint of the line connecting the center of the pressure-sensitive surface of the standard pressure sensor and the pressure sensor to be calibrated, so as to complete the calibration of the center position of the cavitation bubble.

[0058] Then calibrate the sensor to be calibrated. The calibration steps are as follows:

[0059] Step S1: The amplitude parameters A1, A2, A3, the frequency parameters f1, f2, f3, and the acceleration parameters a1, a2, a3 of the three orthogonal axes of the vibration table are independently configured to realize the vibration environment simulation in the orthogonal directions of X, Y, and Z axes.

[0060] Specifically, the displacement control algorithm for a three-axis vibration table allows precise manipulation of the three-degree-of-freedom vibration table to simulate the vibration environment in the orthogonal X / Y / Z directions. The vibration table's displacement Δd in each direction follows simple harmonic motion over time. This algorithm supports continuously adjustable vibration frequency f from 50Hz to 1kHz, variable amplitude A from 1mm to 5mm, and acceleration a from 1.5m / s² to 2m / s² in all three directions, enabling accurate simulation of the in-situ operating vibration environment of underwater pressure sensors. Operators can independently configure key parameters for the three orthogonal axes: amplitude parameters A1, A2, and A3; frequency parameters f1, f2, and f3; and acceleration parameters a1, a2, and a3.

[0061] Step S2: The FPGA controller generates a drive signal and implements independent control of the three orthogonal vibration directions of X, Y, and Z according to the displacement control algorithm of the three-axis vibration table, so that the vibration table can perform sinusoidal motion in the three directions according to preset parameters.

[0062] Specifically, the FPGA controller can generate a driving signal to drive the vibration table to perform sinusoidal motion according to preset parameters. The corresponding relationship between the highest and lowest points of the vibration table's displacement in each direction and the control equation is as follows: Figure 3 As shown, a dynamic excitation environment that is highly matched with the actual working conditions of the sensor is constructed.

[0063] Step S3: Implement high-precision synchronous control of the vibration table movement and laser emission based on the FPGA controller.

[0064] Specifically, a counter within the FPGA monitors the real-time phase angles θ1, θ2, and θ3 of each vibration axis of the current vibration table and determines whether the vibration table has reached the laser trigger position. Each time the vibration table periodically moves to the corresponding laser trigger position, a digital delay trigger immediately sends a trigger signal to the pulsed laser, triggering a single laser pulse. The laser is then focused on the calibration point via an adjustable beam expansion and focusing optical module, synchronizing the vibration table's motion with the laser emission. After passing through the beam expansion and focusing optical module, the laser is precisely focused at the midpoint of the line connecting the pressure-sensitive surfaces of the standard sensor and the sensor to be calibrated, generating cavitation bubbles.

[0065] Step S4: collecting the output signals of the standard sensor and the sensor to be calibrated, and calibrating the pressure sensor to be calibrated by comparing the two output signals.

[0066] Specifically, the standard pressure wave generated by the collapse of the cavitation acts on the pressure-sensitive surface of the pressure sensor. At this time, the sensor signal acquisition device synchronously acquires the output signals of the standard sensor and the sensor to be calibrated. When the natural frequency of the standard pressure sensor is much greater than the natural frequency of the sensor to be calibrated, it is only necessary to obtain the output response signal of the standard pressure sensor. The calibrated pressure sensor outputs a response signal Fourier transform of 、 , the frequency response characteristics of the two sensors can be obtained by comparing the two output signals 、 The relationship between the two is used to calibrate the pressure sensor to be calibrated. The basic principle is as follows.

[0067]

[0068] In the formula is the angular frequency, is the Fourier transform result of the input signal, 、 is the Fourier transform result of the output signal, 、 are the frequency response characteristics of the two sensors.

[0069] Furthermore, the sensor signal acquisition device is a collection device composed of an acquisition card, a signal amplifier and a filter circuit. The signal acquisition device includes collecting the pressure signal of the pressure sensor and monitoring the accuracy of the calibrated sensor.

[0070] Furthermore, the specific principle of the displacement control algorithm of the three-axis vibration table is as follows:

[0071] The displacement control formula of each vibration direction of the vibration table is as follows:

[0072]

[0073] in is the displacement of the vibration table in the vibration direction, f is the vibration frequency, t is the vibration time, and the amplitude A, frequency f, and phase angle θ of each vibration direction are set by the user.

[0074] The acceleration setting method is as follows:

[0075] The relationship between the acceleration a, amplitude A, and frequency f in each direction of the vibration table is:

[0076]

[0077] When the user enters the target acceleration in a certain direction, the vibration frequency of the fixed vibration table in this vibration direction is 400 Hz. Therefore, the FPGA automatically reverses the value of amplitude A according to the following formula and adjusts amplitude A to achieve the required acceleration value.

[0078]

[0079] Furthermore, the beam expansion and focusing optical path module is a device composed of a beam expander, a focusing lens, and a motorized translation stage. The sensor signal acquisition device is a device composed of an acquisition card, a signal amplifier, and a filter circuit. The signal acquisition device collects pressure signals from pressure sensors and monitors the accuracy of the calibrated sensor.

[0080] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions, and variations of these embodiments, including components, without departing from the principles and spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A dynamic calibration method for underwater pressure sensors using three-axis vibration synchronous control, characterized in that: The following steps are involved: Set the trigger phase angles of the three vibration directions of the triaxial vibration table, and the motor drives the vibration table to move to the corresponding position, which is recorded as the laser trigger position; After the vibration table reaches the laser trigger position, it controls the pulsed laser to emit laser light, and uses an ultra-high-speed camera to capture the morphological changes of the cavitation bubble generation and collapse process to obtain the cavitation bubble position information; According to the cavitation bubble position information, adjust the beam expansion and focusing optical path module so that the cavitation bubble center is located on the line connecting the standard pressure sensor and the pressure sensing surface center of the pressure sensor to be calibrated; then adjust the sensor clamping and fine-tuning device so that the cavitation bubble center is at the midpoint of the line to complete the cavitation bubble position calibration; Configure the amplitude parameters, frequency parameters, and acceleration parameters of the three orthogonal axes of the vibration table to simulate the vibration environment in the orthogonal directions of X, Y, and Z axes; The FPGA controller generates drive signals based on set parameters and implements independent control of three orthogonal vibration directions based on the displacement control algorithm of the three-axis vibration table, causing the vibration table to perform sinusoidal motion in the three directions according to preset parameters. An internal counter accurately monitors the real-time phase angle of each vibration axis of the vibration table to determine whether the laser trigger position has been reached. When the vibration table moves periodically to the laser trigger position, the digital delay trigger sends a trigger signal to the pulse laser. The laser enters the water tank through the beam expansion and focusing optical path module, and is precisely focused on the midpoint of the line connecting the pressure-sensitive surfaces of the two sensors to generate cavitation, thus achieving high-precision synchronous control of the vibration table movement and laser emission. The pressure wave generated by the collapse of the cavitation bubble acts on the pressure-sensing surface of the pressure sensor, and the sensor signal acquisition device collects the output signals of the standard sensor and the sensor to be calibrated; Perform Fourier transform on the collected output signals of the two sensors, compare the frequency response characteristics of the two sensors, and complete the calibration of the pressure sensor to be calibrated.

2. The method for dynamic calibration of underwater pressure sensors using three-axis vibration synchronous control according to claim 1, characterized in that: The amplitude parameters of the vibration table range from 1mm to 5mm, the frequency parameters range from 50Hz to 1KHz, and the acceleration parameters range from 1.5m / s² to 2m / s².

3. The method for dynamic calibration of an underwater pressure sensor using three-axis vibration synchronous control according to claim 1 or 2, characterized in that: The synchronization control accuracy of the FPGA controller reaches the millisecond level, ensuring that the relative position of the cavitation bubble generation position and the pressure-sensitive surface of the sensor remains constant each time the vibration table periodically moves to the laser trigger position.

4. The method for dynamic calibration of an underwater pressure sensor using three-axis vibration synchronous control according to claim 1 or 2, characterized in that: The beam expansion and focusing optical path module includes a beam expander, a focusing mirror and an electrically controlled displacement stage. The positions of the beam expander and the focusing mirror are adjusted by adjusting the position of the electrically controlled displacement stage, thereby accurately controlling the generation position of cavitation bubbles.

5. The method for dynamic calibration of underwater pressure sensor using three-axis vibration synchronous control according to claim 2, characterized in that: The sensor clamping and fine-tuning device adopts a double-layer collet structure. By loosening the fixing screws on the outer collet and releasing the inner collet, the vertical degree of freedom of the sensor can be adjusted.

6. The method for dynamic calibration of underwater pressure sensors using three-axis vibration synchronous control according to claim 5, characterized in that: The sensor signal acquisition device includes an acquisition card, a signal amplifier and a filtering circuit, and can synchronously acquire the output signals of the standard sensor and the sensor to be calibrated, and amplify and filter the acquired signals.

7. The method for dynamic calibration of underwater pressure sensors using three-axis vibration synchronous control according to claim 5, characterized in that: The ultra-high-speed camera is combined with a shadow imaging method to monitor the morphological changes of the cavitation bubble generation and collapse process in real time to obtain accurate cavitation bubble position information.

8. A dynamic calibration device for an underwater pressure sensor using three-axis vibration synchronous control, used to implement the method according to any one of claims 1 to 7, characterized in that: include: An electronically controlled three-axis vibration table is used to simulate the in-situ vibration environment of the pressure sensor and provide the vibration conditions required for dynamic calibration; An ultra-high-speed camera, in conjunction with the electrically controlled three-axis vibration table (1), is used to collect morphological changes during the generation and collapse of cavitation bubbles to obtain cavitation bubble position information; An environmental chamber, accommodating the sensor and providing a liquid environment for the calibration process; A pulse laser, in conjunction with the electrically controlled three-axis vibration table (1) and the ultra-high-speed camera (2), for emitting laser light to generate cavitation bubbles; A sensor signal acquisition device, connected to the sensor in the environmental chamber (3), for acquiring output signals of the standard pressure sensor and the pressure sensor to be calibrated; A digital delay trigger, connected to the pulse laser (7) and the electrically controlled three-axis vibration table (1), for sending a trigger signal to the pulse laser when the vibration table reaches a laser trigger position; A beam expansion and focusing optical path module, in conjunction with the pulse laser (7) and the ultra-high-speed camera (2), is used to adjust the focus position of the laser to ensure that cavitation bubbles are generated at the midpoint of the line connecting the standard pressure sensor and the pressure-sensitive surface of the pressure sensor to be calibrated; Sensor clamping and fine-tuning device, used to install and adjust the position of the standard pressure sensor and the pressure sensor to be calibrated; The FPGA controller is connected to the electrically controlled three-axis vibration table (1) and the digital delay trigger (9), and is used to generate a drive signal and realize high-precision synchronous control of the vibration table movement and laser emission, and realize independent control of three orthogonal vibration directions of X, Y, and Z according to the displacement control algorithm of the three-axis vibration table.

9. The underwater pressure sensor dynamic calibration device using three-axis vibration synchronous control according to claim 8, characterized in that: The electrically controlled three-axis vibration table (1) can realize independent vibration control in three orthogonal directions of X, Y, and Z, and supports continuously adjustable vibration frequency from 50 Hz to 1 kHz, variable amplitude from 1 mm to 5 mm, and acceleration setting in the range of 1.5 m / s² to 2 m / s².

10. The underwater pressure sensor dynamic calibration device using three-axis vibration synchronous control according to claim 8 or 9, characterized in that: The sensor clamping and fine-tuning device adopts a double-layer collet structure, including an inner collet (11), an outer collet (12) and a fixing screw (13). By loosening the fixing screw (13) on the outer collet (12), the inner collet (11) is released, thereby achieving vertical freedom adjustment of the sensor.

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