A method and system for monitoring the structure of a movable tail pontoon of a large semi-submersible carrier

Abstract

The present invention discloses a method and system for monitoring the structure of a movable tail pontoon of a large semi-submersible carrier. The method comprises dividing the detection area of ​​the movable tail pontoon system of the semi-submersible carrier, arranging array piezoelectric sensors in each area, and collecting reference signals; collecting the signal of the movable tail pontoon system of the semi-submersible carrier when the tail pontoon system of the semi-submersible carrier is in service; preprocessing the signal, and obtaining a differential signal through the signal in service and the reference signal; solving the bode time series by using the skewed exponential distribution; superimposing and summing the delay matrix by using the bode time series to obtain the imaging result of the detection area; analyzing the structural integrity of the tail pontoon system according to the imaging result, and identifying the damaged area by using the threshold judgment. The system comprises a tail pontoon system module, a medium voltage power supply system, an electric propulsion system module, a pressure displacement system module, a dynamic positioning module and a structural health monitoring module.

Description

Technical Field

[0001] The present invention relates to the technical field of semi-submersible vehicle equipment and structural health detection, and in particular to a method and system for monitoring the structure of a movable tail pontoon of a large semi-submersible vehicle equipment. Background Art

[0002] Semi-submersible carriers are the only means of transporting super-large structures across the ocean. They enjoy the reputation of "forklifts at sea" and are strategic "heavy weapons" for offshore oil and gas development, large bridge and tunnel construction, shipwreck rescue and salvage, and offshore clean energy construction. With the rapid development of marine engineering and deep-sea exploration, semi-submersible carriers play an important role in marine operations. However, during long-term use, semi-submersible carriers will be affected by factors such as marine environment, mechanical wear and accidents, resulting in structural damage. Traditional damage detection methods often rely on manual inspections, which have limited accuracy, slow response speed, difficulty in real-time monitoring, and low reliability under extreme marine conditions. Under the harsh test of the marine environment, any failure of the tail pontoon system of the semi-submersible carrier may pose a threat to the operation of the entire equipment and even the safety of marine operations, resulting in economic losses and environmental risks. Therefore, it is crucial to use new monitoring technologies to monitor semi-submersible carriers in real time during service projects.

[0003] Ultrasonic guided wave testing is a non-destructive testing technology that is widely used in the fields of structural health monitoring, defect detection and material performance evaluation. It is an important application technology in structural monitoring. The use of intelligent ultrasonic guided wave testing technology to monitor semi-submersible carriers aims to monitor the working status of the tail pontoon in real time through intelligent sensor technology and data processing algorithms. It can effectively respond to the health status detection of key structures of semi-submersible carriers under conditions such as variable loads, variable media, variable temperatures and vibrations, improve the accuracy of detection, ensure the safe operation of equipment, improve the operating efficiency and safety of equipment, and reduce operating costs. It is of great significance to improve the technical level of the entire marine engineering industry. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a method and system for monitoring the movable tail pontoon structure of large semi-submersible carrier equipment.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A method for monitoring the structure of a movable tail pontoon of a large semi-submersible carrier, comprising:

[0007] S1 divides the detection area of ​​the movable tail buoy system of the semi-submersible carrier equipment, arranges array piezoelectric sensors in each area, and collects reference signals;

[0008] S2 collects the signal of the movable tail pontoon system of the semi-submersible carrier equipment when the tail pontoon system of the semi-submersible carrier equipment is in service;

[0009] S3 pre-processes the signal and obtains a differential signal through the signal in the service state and the reference signal;

[0010] S4 uses skewed exponential distribution to solve the Boda time series;

[0011] S5 uses the wave arrival time series to stack and sum the delay matrix to obtain the imaging result of the detection area;

[0012] S6 analyzes the structural integrity of the tail pontoon system based on the imaging results and uses threshold judgment to identify the damaged area.

[0013] Furthermore, the S1 includes: arranging array sensors in each detection area of ​​the tail pontoon system, and using the sensor network to obtain ultrasonic guided wave signals in a healthy state of the regional structure as reference signals for structural damage detection;

[0014] The inspection area of ​​the movable tail pontoon system of the semi-submersible carrier equipment includes the tail pontoon wall area, the tail pontoon top area, the tail pontoon connection structure area, the mobile device area, the ballast system pipeline structure area, the ballast tank structure area, the propulsion system main shaft structure area, the propulsion system propeller structure area and the deck structure area.

[0015] Furthermore, S2 includes: using a sensor network to collect key signals of a movable tail pontoon system of a semi-submersible vehicle in service; wherein the service status of the movable tail pontoon system of a semi-submersible vehicle includes the diving and surfacing operation process of the semi-submersible vehicle.

[0016] Further, the S3 includes: preprocessing the signal by smoothing filtering method, eliminating signal noise and abnormal values, aligning the first wave of the service status signal with the reference signal and performing subtraction to obtain a differential signal;

[0017] The smoothing filtering method adopts a moving average filter, and the window size value is a dimensionless value of a small factor of the ultrasonic guided wave signal sampling rate; and

[0018] Each detection area includes a group of array sensors, each group of array sensors includes at least eight piezoelectric sensors, and the piezoelectric sensors are interconnected in pairs to form a sensing network, wherein every two sensors form a sensing path, and each sensor path includes two groups of differential signals.

[0019] Furthermore, in S4, the wave arrival time sequence uses the first wave arrival time t a Solve the skewed exponential distribution, where the exponential distribution parameter is λ, and its value is related to the size of the detection imaging area and the ultrasonic guided wave velocity; before the first wave arrives, that is, t <ta , the tail pontoon structure has no damage, so the value is 0. After the first wave arrives, that is, t>t a , the tail pontoon structure may be damaged, and the possible damage area is similar to t a The farther away from the value, the smaller the probability of damage, so the value decreases exponentially; the skewed exponential distribution formula is:

[0020]

[0021] Where t is the time, and the λ value of the sensor network in a single detection area is consistent.

[0022] Furthermore, S5 includes linearly interpolating the wave arrival time series to the delay matrix of the full sensing network, and then summing the energy values ​​on all sensing paths to obtain the imaging result of the detection area; the larger the energy value in the imaging result, the greater the probability of damage.

[0023] The movable tail pontoon structure monitoring system for large semi-submersible carrier equipment includes the tail pontoon system module, medium voltage power supply system, electric propulsion system module, pressure-displacement system module, dynamic positioning module and structural health monitoring module;

[0024] Structural health monitoring module, used to monitor the tail pontoon system module and the ballast load system module;

[0025] Medium voltage power supply system, used to provide power for the electric propulsion system module, tail pontoon system module, ballast load system module, dynamic positioning module and structural health monitoring module;

[0026] The pressure-displacement system module is used to control the buoyancy and load distribution of the semi-submersible vehicle during the diving and surfacing operations, ensuring the stability of the semi-submersible vehicle during operation and monitoring.

[0027] The dynamic positioning module is used to monitor the position and posture of semi-submersible transportation equipment in real time to ensure the stable and safe operation of the semi-submersible transportation equipment.

[0028] Furthermore, the structural health monitoring module includes an array piezoelectric sensor module, a signal generator module, a power amplifier module, a charge amplifier module, a data acquisition module, an acoustic control module and a computer;

[0029] The piezoelectric sensor module includes a plurality of piezoelectric sensor modules, which are arrayed and distributed in each tail pontoon detection area and are used to excite and receive ultrasonic signals;

[0030] The signal generator module is used to generate an ultrasonic signal;

[0031] The acoustic control module is used to control the wave field of the ultrasonic guided wave.

[0032] Furthermore, the wave field control of the ultrasonic guided wave is achieved by changing the structural parameters, shape parameters, material properties, and arrangement position; the wave field control includes acoustic impedance matching, acoustic directional transmission, acoustic focusing, acoustic shielding, and acoustic mode conversion.

[0033] Furthermore, at the excitation end, the signal generator module is connected to the power amplifier module, and the power amplifier module is connected to the piezoelectric sensor module; at the receiving end, the piezoelectric sensor module is connected to the charge amplifier module, and then connected to the data acquisition module and the computer; the sound control module is arranged between the piezoelectric sensor module and the tail pontoon system module, or on the tail pontoon system module.

[0034] Compared with the prior art, one or more embodiments of the present invention may have the following advantages:

[0035] The present invention divides the key structures of each system of the semi-submersible vehicle into detection areas, adopts ultrasonic guided wave detection technology, arranges array piezoelectric sensors in each area, collects and processes ultrasonic guided wave signals, and realizes health status monitoring of the tail pontoon structure.

[0036] The method of the present invention is suitable for structural health monitoring of semi-submersible carrier equipment during diving and surfacing operations, and can effectively cope with working conditions such as variable loads, variable media, variable temperatures and vibrations.

[0037] The time-delay stacking imaging method based on wave arrival time series proposed in the present invention can effectively solve the problem of excessive positioning area caused by modal aliasing of detection signals in various complex key structures of the tail pontoon system, and realize accurate detection and positioning of structural damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a flow chart of the monitoring method of the movable tail pontoon structure of large semi-submersible carrier equipment;

[0039] Figure 2 It is a schematic diagram of the structure monitoring system of the movable tail pontoon of a large semi-submersible carrier;

[0040] Figure 3 It is a structural diagram of the double-layer metal hull with a movable tail pontoon system;

[0041] Figure 4 It is a schematic diagram of the detection area image matrix;

[0042] Figure 5 It is a diagram of the signal processing process;

[0043] Figure 6 It is a Boda time series graph;

[0044] Figure 7a is a schematic diagram of the imaging results of the detection area;

[0045] Figure 7b It is a schematic diagram of the damaged area after 99.97% threshold processing. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with embodiments and drawings.

[0047] like Figure 1 The figure shows the process of monitoring the structure of the movable tail pontoon of large semi-submersible carrier equipment, including:

[0048] Step 10: dividing the detection area of ​​the tail pontoon system of the semi-submersible carrier equipment, arranging array piezoelectric sensors in each area, and collecting reference signals;

[0049] Step 20 collects the signal of the semi-submersible carrier equipment tail pontoon system when the semi-submersible carrier equipment movable tail pontoon system is in service;

[0050] Step 30 pre-processes the signal and obtains a differential signal by comparing the signal in the service state with the reference signal;

[0051] Step 40 uses skewed exponential distribution to solve the boda time series;

[0052] Step 50 uses the wave arrival time series to perform superposition and summation on the delay matrix to obtain the imaging result of the detection area;

[0053] Step 60 analyzes the structural integrity of the tail pontoon system according to the imaging results, and identifies the damaged area using a threshold value.

[0054] In the above step 10, array sensors are arranged in each detection area of ​​the tail pontoon system, and the ultrasonic guided wave signal of the regional structure in a healthy state is obtained by using the sensor network as a reference signal for structural damage detection.

[0055] The detection area of ​​the movable tail pontoon system of the semi-submersible carrier equipment includes the tail pontoon wall area, the tail pontoon top area, the tail pontoon connection structure area, the mobile device area, the pressure-displacement system pipeline structure area, the ballast tank structure area, the propulsion system main shaft structure area, the propulsion system propeller structure area and the deck structure area. The array sensor adopts a piezoelectric sensor to excite the ultrasonic guided wave signal in the structure of the area; the damage detection method is an array piezoelectric ultrasonic guided wave intelligent detection technology; the ultrasonic guided wave signal in the healthy state of the structure of the area is obtained by using a sensor network as a reference signal for structural damage detection.

[0056] The above 20 includes: using a sensor network to collect key signals of a movable tail pontoon system of a semi-submersible vehicle in a service state; wherein, the service state of the movable tail pontoon system of a semi-submersible vehicle includes the diving and surfacing operation process of the semi-submersible vehicle, and the working conditions encountered include but are not limited to variable loads, variable media, variable temperatures and vibrations; and obtaining ultrasonic guided wave signals in a service state through a piezoelectric array sensor.

[0057] Step 30 includes: preprocessing the signal by smoothing filtering method to eliminate signal noise and abnormal values, aligning the first wave of the service status signal with the reference signal and performing subtraction to obtain a differential signal;

[0058] The smoothing filtering method adopts a moving average filter, and the window size value is a dimensionless value of a small factor of the ultrasonic guided wave signal sampling rate.

[0059] Each detection area includes a group of array sensors, each group of array sensors includes n (n≥8) piezoelectric sensors, and the piezoelectric sensors are interconnected in pairs to form a sensing network, wherein every two sensors form a sensing path, and each sensor path includes two groups of differential signals.

[0060] In the above step 40, the ultrasonic guided wave flight time from each detection point in the detection area to each sensing path is solved to obtain the delay matrix of the entire sensing network; the absolute value threshold of the differential signal is used to solve the first wave arrival time t a ; Using the first wave arrival time t a Generate wave arrival time series to facilitate the detection of key structural damage in the tail pontoon system.

[0061] The wave arrival time series uses the first wave arrival time t a Solve the skewed exponential distribution, as shown in formula (1), λ is the exponential distribution parameter, and its value is related to the size of the detection imaging area and the ultrasonic guided wave velocity; before the first wave arrives, that is, t <t a , the tail pontoon structure has no damage, so the value is 0. After the first wave arrives, that is, t>t a , the tail pontoon structure may be damaged, and the possible damage area is similar to t a The farther away from this value, the smaller the probability of damage, so the value decreases exponentially; the value of λ of the sensor network in a single detection area is consistent and consistent with (tt in formula (1) a ) items together ensure that the signal size of each sensing path in the detection area is classified as equal energy level.

[0062]

[0063] Where t is the time. The λ value of the sensor network in a single detection area is consistent.

[0064] The above step 50 includes linearly interpolating the wave arrival time series to the delay matrix of the full sensor network, and then summing the energy values ​​on all sensor paths to obtain the imaging result of the detection area; the larger the energy value in the imaging result, the greater the probability of damage; and using the threshold judgment to identify the area in the key structure of the tail pontoon system that may eventually be damaged.

[0065] like Figure 2 As shown, this embodiment also provides a large-scale semi-submersible carrier equipment movable tail pontoon structure monitoring system, including: a movable tail pontoon system module, an electric propulsion system module, a ballast load system module, a dynamic positioning system module, and a structural health monitoring module; the structural health monitoring module can monitor the pontoon structure unit, the connection and fixing unit, the sealing structure unit, and the movable track unit of the tail pontoon module, monitor the main shaft propulsion unit and the propeller unit of the electric propulsion system module, monitor the ballast tank structure and the ballast pipeline structure of the ballast load system module, and monitor the propeller structure of the dynamic positioning system; the medium voltage power supply unit provides a suitable power supply for the electric propulsion system module, the tail pontoon module, the ballast load system module, the dynamic positioning system module, and the structural health detection module. Control the buoyancy and load distribution during the diving and floating operations of the semi-submersible carrier equipment to ensure the stability of the semi-submersible carrier equipment in the operation and monitoring states;

[0066] Dynamic positioning module, used to monitor the position and posture of semi-submersible vehicles in real time to ensure stable and safe operation of semi-submersible vehicles

[0067] The structural health monitoring module includes a piezoelectric sensor module, a signal generator module, a power amplifier module, a charge amplifier module, a data acquisition module, a sound control module, and a computer, and the required power is provided by a medium voltage power supply system module.

[0068] The signal generator module is connected to the power amplifier module, and the power amplifier module is connected to the piezoelectric sensor module; at the receiving end, the piezoelectric sensor module is connected to the charge amplifier module, and then connected to the data acquisition module and the computer; the sound control module can be arranged between the piezoelectric sensor module and the tail pontoon structure, or arranged on the tail pontoon structure, to achieve the wave field control of the ultrasonic guided wave. The piezoelectric sensor module is provided with multiple arrays distributed in each tail pontoon detection area, which are used to excite and receive ultrasonic guided wave signals; the signal generator module is used to generate ultrasonic guided wave signals; the sound control module can realize the wave field control function of ultrasonic guided waves by changing the structural parameters, shape parameters, material properties, and layout position; the wave field control includes acoustic impedance matching, acoustic directional transmission, acoustic focusing, acoustic shielding, and acoustic mode conversion.

[0069] Further explanation through specific examples:

[0070] like Figure 3As shown in Figure 1, it is a double-layer metal hull structure of the movable tail pontoon system, and 8 piezoelectric sensors are pasted on the surface. The sensor parameters are shown in Table 1. The sound control module is an ultrasonic guided wave shielding metamaterial, and the ultrasonic guided wave excitation signal is a 10-cycle Hanning window modulation signal with a center frequency of 200kHz.

[0071] Table 1 Piezoelectric sensor property parameters

[0072]

[0073] Note: d 33 is the piezoelectric strain coefficient, ε T 33 / ε0Relative dielectric constant, tg δ % is dielectric loss, K p , K t is the electromechanical coupling coefficient, Q m is the mechanical quality factor, T c is the Curie temperature.

[0074] like Figure 4 As shown, the current detection area is expanded, and a two-dimensional image matrix is ​​constructed according to the expanded detection area. The image matrix contains m×n discrete points, and formula (3) is obtained:

[0075] P=(x,y)(2)

[0076]

[0077] The sensor network is used to obtain the ultrasonic guided wave signal of the healthy state of the structure in the area as the reference signal for structural damage detection.

[0078] Then obtain the piezoelectric array sensor to obtain the ultrasonic guided wave signal in the service state.

[0079] The sampling rate of the received signal is 8MS / s, and the window value of the moving average filter is 32. The service status signal and the reference signal are aligned and subtracted to obtain a differential signal, such as Figure 5 shown.

[0080] The ultrasonic guided wave flight time from each detection point to each sensing path in the detection area is solved by equation (4) to obtain the delay matrix of the entire sensing network; where c g is the velocity of ultrasonic guided waves propagating in the structure.

[0081]

[0082] like Figure 6 As shown, it is beneficial to solve the first wave arrival time t by using the absolute value threshold of the differential signal a ; Using the first wave arrival time t aGenerate the arrival time series. Among them, the formula (5) is used to generate the arrival time series, λ is the exponential distribution parameter, and its value is 0.02.

[0083]

[0084] Where t is time, λ is the exponential distribution parameter, t a is the first wave arrival time.

[0085] The energy value of the current sensing path is obtained by linearly interpolating the arrival time series of formula (6) to the delay matrix of the entire sensor network.

[0086] E i =E i-1 +INTERP(t,f i (t,λ),D i ,linear,0)(6)

[0087] Among them, E i is the energy value on the current sensing path, INTERP is the interpolation function, linear represents linear interpolation, D i is the delay matrix.

[0088] The energy values ​​on all sensing paths are summed up by formula (7) to obtain the imaging result of the detection area, as follows: Figure 7a As shown in the figure, the larger the energy value in the imaging result, the greater the probability of damage. The imaging result is selected by using the 99.97% threshold, and finally the damaged area in the tail pontoon system structure is identified, as shown in the figure. Figure 7b Show.

[0089]

[0090] Although the embodiments disclosed in the present invention are as above, the above contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for monitoring the movable tail pontoon structure of a large semi-submersible carrier, characterized in that: The following steps are involved: S1 divides the detection area of ​​the movable tail buoy system of the semi-submersible carrier equipment, arranges array piezoelectric sensors in each area, and collects reference signals; S2 collects the signal of the movable tail pontoon system of the semi-submersible carrier equipment when the tail pontoon system of the semi-submersible carrier equipment is in service; S3 pre-processes the signal and obtains a differential signal through the signal in the service state and the reference signal; S4 uses the first wave arrival time t a Solve the skewed exponential distribution and use the skewed exponential distribution to solve the Boda time series; S5 uses the wave arrival time series to stack and sum the delay matrix to obtain the imaging result of the detection area; S6 analyzes the structural integrity of the tail pontoon system based on the imaging results and identifies the damaged area using threshold judgment; In S4, the first wave arrival time t is used a Solve the skewed exponential distribution, where the exponential distribution parameter is λ, and the value of λ is related to the size of the detection imaging area and the ultrasonic guided wave velocity; before the first wave arrives, that is, t <t a , the tail pontoon structure has no damage, so the skewed exponential distribution takes the value of 0. After the first wave arrives, that is, t>t a , the tail pontoon structure may be damaged, and the possible damage area is similar to t a Related, the farther away from t a The smaller the value, the smaller the probability of damage, so the skewed exponential distribution takes exponential decreasing values; the skewed exponential distribution formula is: Where t is the time, and the λ value of the sensor network in a single detection area is consistent.

2. The method for monitoring the movable tail pontoon structure of large semi-submersible carrier equipment according to claim 1 is characterized in that: S1 includes: arranging array sensors in each detection area of ​​the tail pontoon system, and using the sensor network to obtain ultrasonic guided wave signals in a healthy state of the regional structure as reference signals for structural damage detection; The inspection area of ​​the movable tail pontoon system of the semi-submersible carrier equipment includes the tail pontoon wall area, the tail pontoon top area, the tail pontoon connection structure area, the mobile device area, the ballast system pipeline structure area, the ballast tank structure area, the propulsion system main shaft structure area, the propulsion system propeller structure area and the deck structure area.

3. The method for monitoring the movable tail pontoon structure of large semi-submersible carrier equipment according to claim 1 is characterized in that: The S2 includes: using a sensor network to collect key signals of a movable tail pontoon system of a semi-submersible vehicle in service; wherein the service status of the movable tail pontoon system of a semi-submersible vehicle includes the diving and surfacing operation process of the semi-submersible vehicle.

4. The method for monitoring the movable tail pontoon structure of large semi-submersible carrier equipment according to claim 1 is characterized in that: The step S3 includes: preprocessing the signal by smoothing filtering method to eliminate signal noise and abnormal values, aligning the first wave of the service status signal with the reference signal and performing subtraction to obtain a differential signal; The smoothing filtering method adopts a moving average filter, and the window size value is a dimensionless value of a small factor of the ultrasonic guided wave signal sampling rate; and Each detection area includes a group of array sensors, each group of array sensors includes at least eight piezoelectric sensors, and the piezoelectric sensors are interconnected in pairs to form a sensing network, wherein every two sensors form a sensing path, and each sensor path includes two groups of differential signals.

5. The method for monitoring the movable tail pontoon structure of large semi-submersible carrier equipment according to claim 1 is characterized in that: The S5 includes linearly interpolating the wave arrival time series to the delay matrix of the full sensing network, and then summing the energy values ​​on all sensing paths to obtain the imaging result of the detection area; the larger the energy value in the imaging result, the greater the probability of damage.

6. A monitoring system used in a method for monitoring a movable tail pontoon structure of a large semi-submersible carrier according to any one of claims 1 to 5, characterized in that: It includes the tail pontoon system module, medium voltage power supply system, electric propulsion system module, pressure-displacement system module, dynamic positioning module and structural health monitoring module; Structural health monitoring module, used to monitor the tail pontoon system module and the ballast load system module; Medium voltage power supply system, used to provide power for the electric propulsion system module, tail pontoon system module, ballast load system module, dynamic positioning module and structural health monitoring module; The pressure-displacement system module is used to control the buoyancy and load distribution of the semi-submersible vehicle during the diving and surfacing operations; The dynamic positioning module is used to monitor the position and attitude of semi-submersible transport equipment in real time.

7. The large semi-submersible carrier movable tail pontoon structure monitoring system according to claim 6 is characterized in that: The structural health monitoring module includes an array piezoelectric sensor module, a signal generator module, a power amplifier module, a charge amplifier module, a data acquisition module, a sound control module and a computer; The piezoelectric sensor module includes a plurality of piezoelectric sensor modules, which are arrayed and distributed in each tail pontoon detection area and are used to excite and receive ultrasonic signals; The signal generator module is used to generate an ultrasonic signal; The acoustic control module is used to control the wave field of the ultrasonic guided wave.

8. The large semi-submersible carrier movable tail pontoon structure monitoring system according to claim 7 is characterized in that: The wave field control of the ultrasonic guided wave is achieved by changing the structural parameters, shape parameters, material properties and layout position of the acoustic control module; the wave field control includes acoustic impedance matching, acoustic directional transmission, acoustic focusing, acoustic shielding and acoustic mode conversion.

9. The large semi-submersible carrier movable tail pontoon structure monitoring system according to claim 7 is characterized in that: At the excitation end, the signal generator module is connected to the power amplifier module, and the power amplifier module is connected to the piezoelectric sensor module; at the receiving end, the piezoelectric sensor module is connected to the charge amplifier module, and then connected to the data acquisition module and the computer; the sound control module is arranged between the piezoelectric sensor module and the tail pontoon system module, or on the tail pontoon system module.

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