Ship propeller pulsating pressure measuring device and ship navigation state monitoring method

Abstract

The invention provides a ship propeller pulsating pressure measuring device and a ship navigation state monitoring method, and the measuring device comprises a mounting base, a rapid connection assembly and a housing. One end of the mounting base is fixed on a preset measuring point position of a ship hull plate; the quick connecting assembly is arranged at the other end of the mounting base, one end of the quick connecting assembly is provided with a pressure sensor, the other end of the quick connecting assembly is clamped and fixed with the other end of the mounting base, so that the pressure sensor is detachably connected with the mounting base, and the pressure sensor is in communication connection with the central control system through a signal cable pre-embedded in the mounting base; pulsating pressure signals of the ship propeller are monitored in real time; the pressure sensor is sleeved with the shell, and one end of the shell is fixedly connected with one end of the quick connecting assembly. According to the scheme provided by the invention, the ship propeller pulsating pressure monitoring cost can be reduced, the monitored propeller pulsating pressure and the operation parameters are subjected to fusion processing and identification, and a basis is provided for safe and green operation of a ship.

Description

Technical Field

[0001] This invention relates to the field of ship navigation status monitoring technology, specifically to a device for measuring ship propeller pulsation pressure and a method for monitoring ship navigation status. Background Technology

[0002] Propeller pulsating pressure is a major excitation source causing ship vibration, and its accurate measurement is crucial for ship design and vibration reduction. Currently, ship-based measurements primarily employ direct sensor installation, which often presents several drawbacks: 1. Installation difficulties: Drilling or welding into the hull is required, damaging the hull structure and posing a risk of leakage. 2. Non-reusability: Sensors are typically installed only once and are difficult to recover for use on other vessels, resulting in high costs. 3. Low measurement efficiency: Installation and disassembly are time-consuming and labor-intensive, impacting testing cycles.

[0003] Furthermore, due to the lack of a reliable and stable method for obtaining high-quality ship propeller pulsation pressure over a long period, the understanding of critical states such as ship propeller cavitation remains at a reactive, offline, and one-sided stage, failing to serve the real-time safety and energy efficiency optimization of ships. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a device for measuring the pulsating pressure of a ship propeller and a method for monitoring the ship's navigation status, so as to monitor the pulsating pressure of the ship propeller in real time and accurately, reduce the cost of existing monitoring equipment, and at the same time, combine operating parameters for fusion processing and identification, so as to provide a basis for the safe and green operation of ships.

[0005] To address the aforementioned technical problems, embodiments of the present invention provide a measuring device for ship propeller pulsation pressure, comprising:

[0006] The mounting base is fixed at one end to a preset monitoring point on the hull plate.

[0007] A quick-connect assembly is located at the other end of the mounting base. A pressure sensor is mounted on one end of the quick-connect assembly, and the other end of the quick-connect assembly can be snapped into and fixed to the other end of the mounting base, enabling a detachable connection between the pressure sensor and the mounting base. The pressure sensor is communicatively connected to the central control system via a signal cable pre-embedded in the mounting base to monitor the pulsating pressure signal of the ship's propeller in real time.

[0008] The housing is fitted over the pressure sensor, and one end of the housing is fixedly connected to one end of the quick-connect assembly.

[0009] In one embodiment, the fast connection component includes:

[0010] A first flange is fitted onto one end of the outer casing, and the first flange has a plurality of first bolt holes.

[0011] A second flange is disposed opposite to the first flange, and the second flange has a plurality of second threaded holes corresponding to the first threaded holes; and

[0012] Multiple locking lugs are evenly distributed on the other end of the second flange so as to be snapped and fixed to the other end of the mounting base.

[0013] In one embodiment, the other end of the mounting base is provided with a plurality of guide structures, which are evenly distributed on the other end of the mounting base. Each guide structure corresponds to a locking lug and can be engaged and fixed with the locking lug.

[0014] In one embodiment, each guide structure includes:

[0015] A guide groove is provided at the other end of the mounting base, and the shape of the guide groove matches the shape of the end of the locking lug.

[0016] A limiting block is disposed within the guide groove and located at one end of the guide groove;

[0017] A locking pin is disposed on one side of the guide groove, with one end of the locking pin located inside the guide groove and the other end located outside the guide groove; and

[0018] An elastic element is disposed between the guide groove and the other end of the locking pin, and is sleeved on the outside of the other end of the locking pin; when the locking lug is inserted and moves along the guide groove to the position of the limiting block, the locking pin is pressed to squeeze the elastic element, and under the elastic action of the elastic element, one end of the locking pin is engaged and fixed with the end of the locking lug.

[0019] In one embodiment, the device for measuring the pulsating pressure of the ship propeller further includes:

[0020] A preamplifier is disposed inside the housing. One end of the preamplifier is communicatively connected to the pressure sensor, and the other end of the preamplifier is electrically connected to the signal sensor via a cable adapter terminal.

[0021] In one embodiment, the housing is configured as a streamlined fairing shape, and the surface of the housing is coated with an anti-fouling coating; and / or

[0022] The mounting base is equipped with an underwater wet-plug electrical connector, one end of which is connected to the signal cable, and the other end is snapped into the cable adapter terminal.

[0023] Embodiments of the present invention also provide a method for monitoring ship navigation status based on ship propeller pulsation pressure, comprising the following steps:

[0024] Within a preset time period, the pulsating pressure signal of the propeller and the operating parameters of the ship's navigation system are acquired during the ship's navigation. The pulsating pressure signal is obtained by monitoring the ship propeller pulsating pressure measurement device described in the above embodiment. The operating parameters include the ship's speed, acceleration, rudder angle, engine speed, and ship's draft.

[0025] Based on the pulsating pressure signal and the operating parameters, a multidimensional feature vector is determined when the ship is sailing within a preset time period. The multidimensional feature vector includes multiple feature values.

[0026] Based on the multidimensional feature vector, target navigation events that occur when the ship is sailing within a preset time period are determined; the target navigation events include cavitation events, steering events, and emergency stop events.

[0027] In one embodiment, based on the pulsating pressure signal and the operating parameters, determining the multidimensional feature vector of the ship during navigation within a preset time period includes:

[0028] The pulsating pressure signal is subjected to time-domain features, frequency-domain features, and time-frequency features extraction to obtain at least one pulsating pressure feature value of the pulsating pressure signal;

[0029] Feature extraction is performed on the operation parameters to obtain at least one operation feature value of the operation parameters;

[0030] Based on the pulsating pressure signal, the operating parameters, at least one of the pulsating pressure characteristic values, and at least one of the operating characteristic values, a composite characteristic value is determined when the ship is sailing within a preset time period;

[0031] The multidimensional feature vector is determined based on at least one of the pulsating pressure feature values, at least one of the operational feature values, and the composite feature value.

[0032] In one embodiment, determining the target navigation event that occurs when a ship is sailing within a preset time period based on the multidimensional feature vector includes:

[0033] When the comprehensive cavitation index in the multidimensional feature vector is greater than the cavitation index threshold, the rate of change of rotation speed in the multidimensional feature vector is greater than the rate of change of rotation speed, and the shallow water factor in the multidimensional feature vector is less than the shallow water factor threshold, it is determined that a cavitation event has occurred during the ship's navigation within a preset time period.

[0034] When the rate of change of rudder angle in the multidimensional feature vector is greater than the threshold of the rate of change of rudder angle and the absolute value of the rudder angle in the multidimensional feature vector is greater than the threshold of the rudder angle, it is determined that the ship has experienced a rudder turning event while sailing within a preset time period.

[0035] When the rate of change of rotational speed in the multidimensional feature vector is less than the rate of change of rotational speed threshold, it is determined that the ship has experienced an emergency stop event while sailing within a preset time period.

[0036] In one embodiment, the ship navigation status monitoring method based on ship propeller pulsation pressure further includes:

[0037] Based on the target navigation event, the target monitoring mode of the measuring device and the target sampling frequency of the ship control system are determined, and the monitoring data under the target monitoring mode and the target sampling frequency are output; the monitoring mode of the measuring device includes a background monitoring mode and a fine capture mode, and the sampling frequency of the ship control system includes a first preset sampling frequency and a second preset sampling frequency, wherein the first preset sampling frequency is less than the second preset sampling frequency.

[0038] The above-described solution of the present invention has at least the following beneficial effects:

[0039] 1. The measuring device provided by the present invention has a modular and detachable connection design, which reduces the installation time of the measuring device on the one hand, and allows the sensor unit in the measuring device to be completely recovered on the other hand. This significantly reduces the cost of frequent sensor replacement or docking maintenance, and also greatly simplifies the deployment and subsequent maintenance process, making the large-scale fleet application of the measuring device possible.

[0040] 2. The measuring device provided by the present invention ensures the accuracy and authenticity of the collected pulsating pressure signal from the source by setting a protective shell in the shape of a flow guide, an amplifier, and a quick connection component, providing a reliable input for complex intelligent data analysis and processing in the back end.

[0041] 3. The condition monitoring method provided by this invention deeply integrates the precise pulsating pressure monitored by the propeller measuring device with the ship's operating parameters, realizing laboratory-level refined monitoring capabilities. It solves the multi-dimensional contradictions of traditional methods in terms of real-time performance, accuracy, economy, and scalability, and provides data support and theoretical basis for the intelligent management and safety assurance of ship propulsion systems.

[0042] It should be understood that the implementation of any embodiment of the present invention does not mean that it will simultaneously possess or achieve multiple or all of the above-mentioned beneficial effects. Attached Figure Description

[0043] Figure 1This is a schematic diagram of the measuring device provided in an embodiment of the present invention installed on the outer plate of a ship.

[0044] Figure 2 This is a schematic diagram of the overall structure of the measuring device provided in an optional embodiment of the present invention;

[0045] Figure 3 This is an exploded view of a measuring device provided in an optional embodiment of the present invention;

[0046] Figure 4 This is a cross-sectional view of a measuring device provided in an optional embodiment of the present invention;

[0047] Figure 5 This is an exploded view of the measuring device provided in an optional embodiment of the present invention from another perspective;

[0048] Figure 6 This is a schematic diagram of the structure of the locking lug when it is inserted into the guide groove and not rotated, according to an optional embodiment of the present invention;

[0049] Figure 7 This is a schematic diagram of the structure after the locking lug is inserted into the guide groove and rotated by an angle according to an optional embodiment of the present invention;

[0050] Figure 8 This is a schematic diagram of the locking lug and guide groove engaging in an optional embodiment of the present invention;

[0051] Figure 9 This is a flowchart of a ship navigation status monitoring method based on ship propeller pulsating pressure provided in an embodiment of the present invention;

[0052] Figure 10 This is a schematic block diagram of the electronic device provided in the embodiments of the present invention;

[0053] Figure 11 This is a schematic block diagram of a computing device provided in an embodiment of the present invention.

[0054] Reference numerals: 1. Hull plate; 2. Mounting base; 21. Guide groove; 22. Limiting block; 23. Locking pin; 24. Underwater wet-plug electrical connector; 3. Quick-connect assembly; 31. First flange; 32. Second flange; 33. Locking lug; 34. Locking pin hole; 4. Pressure sensor; 5. Signal cable; 6. Housing; 7. Preamplifier; 8. Cable adapter terminal; 9. Propeller; 10. First sealing ring; 11. Second sealing ring. Detailed Implementation

[0055] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0056] In the description of this invention, it should be understood that the terms "comprising / including," "consisting of," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements includes not only those elements but may also include, where necessary, other elements not expressly listed, or elements inherent to such a product, apparatus, process, or method. Without further limitation, an element defined by the phrases "comprising / including," "consisting of," does not exclude the presence of additional identical elements in the product, apparatus, process, or method that includes said element.

[0057] It should also be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device, component or structure referred to must have a specific orientation, be constructed or operated in a specific orientation, and should not be construed as a limitation of the present invention.

[0058] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0059] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0060] See Figure 1 and Figure 2This invention provides a device for measuring the pulsating pressure of a ship propeller, which may include a mounting base 2, a quick-connect assembly 3, and a housing 6. One end of the mounting base 2 is fixed to a preset monitoring point on the hull hull 1. Preferably, this preset monitoring point is above the propeller disk of the propeller 9 to ensure the representativeness of the monitored pulsating pressure signal, and setting the preset monitoring point above the propeller disk minimizes the impact on hull resistance. Here, one end of the mounting base 2 may be welded and fixed above the propeller disk of the propeller 9, rigidly connected to the hull structure through welding, so that the mounting base 2 can withstand long-term high-speed water flow impact. Furthermore, welding the mounting base 2 to the hull structure avoids drilling holes in the hull structure, reducing damage to the hull.

[0061] A quick-connect component 3 is located at the other end of the mounting base 2. A pressure sensor 4 is installed at one end of the quick-connect component 3, and the other end of the quick-connect component 3 can be snapped into and fixed to the other end of the mounting base 2 to achieve a detachable connection between the pressure sensor 4 and the mounting base 2. The pressure sensor 4 is connected to the central control system via a signal cable 5 embedded in the mounting base 2 to monitor the pulsating pressure signal of the ship's propeller in real time. Here, the signal cable 5 is embedded in the hull structure, and the pulsating pressure signal collected by the pressure sensor 4 can be stably transmitted through the embedded signal cable 5. Here, the pressure sensor can be a piezoelectric pressure sensor, a fiber optic pressure sensor, etc., and there is no specific limitation.

[0062] By setting up the quick-connect component 3, on the one hand, the connection can be made secure and the sealing can be made reliable, and on the other hand, the pressure sensor 4 can be quickly installed and removed, reducing the installation cost; at the same time, the quick-connect component 3 allows the pressure sensor 4 to be independently recovered for use in the next ship monitoring, which greatly reduces the cost of a single test.

[0063] The housing 6 is fitted over the pressure sensor 4, and one end of the housing 6 is fixedly connected to one end of the quick-connect assembly 3. Preferably, a first sealing ring 10 is provided between the other end of the housing 6 and the pressure sensor 4 to ensure the airtightness of the cavity inside the housing 6 and to protect the components inside the cavity of the housing 6.

[0064] In an optional embodiment, the outer shell 6 can be configured as a streamlined flow guide shape to reduce water flow impact vibration and cavitation erosion, ensuring the accuracy of pulsating pressure signal monitoring; and the surface of the outer shell 6 is coated with an antifouling coating to effectively inhibit the attachment of organisms such as shellfish and algae, preventing the sensitive membrane from being covered or the flow channel from being blocked; preferably, the outer shell can be made of high-strength stainless steel or titanium alloy, which can resist salt spray corrosion and ensure long-term service, and can also effectively protect the encapsulated devices inside.

[0065] The measuring device provided in this embodiment, through the flow-stabilizing effect of the dome-shaped shell 6, the detachable connection of the quick-connect assembly 3, and the secure installation of the mounting base 2, ensures from the source that the acquired pulsating pressure signal is high-fidelity, low-noise, and accurate pulsating pressure data. This provides reliable input data for complex intelligent analysis algorithms in the backend, thereby ensuring the accuracy of backend data analysis. Simultaneously, the combination of the "one-time installation, permanent use" mounting base 2 and the "underwater quick-change" pressure sensor connection assembly (quick-connect assembly 3) simplifies the deployment and subsequent maintenance process of the measuring device, making large-scale fleet application of the measuring device possible.

[0066] See Figures 3 to 5 In an optional embodiment of the present invention, the quick-connect assembly 3 may include a first flange 31, a second flange 32, and a plurality of locking lugs 33. The first flange 31 is fitted onto one end of the housing 6 and has a plurality of first threaded holes. The second flange 32 is disposed opposite to the first flange 31 and has a plurality of second threaded holes corresponding to the first threaded holes. The plurality of locking lugs 33 are evenly distributed at the other end of the second flange 32 to be snapped into and fixed to the other end of the mounting base 2.

[0067] In this embodiment, the quick-connect assembly 3 uses a flange snap-fit ​​design to ensure the secure installation of the pressure sensor 4. Preferably, a second sealing ring 11 is provided between the first flange 31 and the second flange 32 to further ensure the sealing of the cavity of the housing 6, thereby protecting the components inside the cavity of the housing 6. Here, multiple locking lugs 33 are evenly distributed on the other end of the second flange 32. Preferably, the locking lugs 33 can be configured as three-dimensional L-shaped claws to achieve a detachable connection with the other end of the mounting base 2.

[0068] See Figures 5 to 8 In an optional embodiment of the present invention, a plurality of guide structures are provided at the other end of the mounting base 2. The plurality of guide structures are evenly distributed at the other end of the mounting base 2. The guide structures correspond one-to-one with the locking lugs 33 and can be snapped and fixed with the locking lugs 33.

[0069] See Figures 6 to 8 In an optional embodiment of the present invention, each guide structure may include a guide groove 21, a limiting block 22, a locking pin 23, and an elastic element. The guide groove 21 is formed at the other end of the mounting base 2, and its shape matches the shape of the end of the locking lug 33. The limiting block 22 is disposed within the guide groove 21 and located at one end of the guide groove 21. The locking pin 23 is disposed on one side of the guide groove 21, with one end of the locking pin 23 located inside the guide groove 21 and the other end located outside the guide groove 21. The elastic element is disposed between the guide groove 21 and the other end of the locking pin 23, and is sleeved on the outside of the other end of the locking pin 23.

[0070] Preferably, a locking pin hole 34 matching one end of the locking lug 33 (the end that is detachably connected to the other end of the mounting base 2) is provided on one end of the locking lug 33. When the locking lug 33 is not installed in the guide groove 21, the elastic element is in an extended state. When the locking lug 33 is inserted and moves along the guide groove 21, after one end of the locking lug 33 contacts the locking pin 23, it will squeeze the locking pin 23 and the elastic element, causing one end of the locking pin 23 to partially detach from the guide groove 21 (at this time, the elastic element connects the locking pin 23 completely, preventing the locking pin 23 from completely detaching from the guide groove 21). As the locking lug 33 continues to move along the guide groove 21 and toward the limiting block 22, when the locking pin hole 34 moves to the position of the locking pin 23, the locking pin 23 is inserted into the locking pin hole 34 under the elastic force of the elastic element. Under the elastic force of the elastic element, one end of the locking pin 23 is engaged and fixed with the end of the locking lug 33, thereby realizing the connection between the mounting base 2 and the quick connection assembly 3.

[0071] Here, the guide groove 21 can be set as a J-shaped guide groove. Preferably, the width of the guide groove 21 matches the end width of the horizontal bottom of the L-shaped claw corresponding to the locking lug 33, and the length of the guide groove 21 is greater than the end length of the horizontal bottom of the L-shaped claw corresponding to the locking lug 33, so that the locking lug 33 can rotate along the length direction of the guide groove 21 after being inserted into the guide groove 21, so that the limiting block 22, the locking pin 23 and the elastic element can cooperate to realize the detachable connection between the quick connection component 3 and the mounting base 2.

[0072] See Figures 3 to 5 In an optional embodiment of the present invention, the above-mentioned device for measuring the pulsating pressure of a ship propeller may further include a preamplifier 7. Here, the preamplifier 7 is disposed inside the housing 6, one end of the preamplifier 7 is communicatively connected to the pressure sensor 4, and the other end of the preamplifier 7 is connected to the signal cable 5 through a cable adapter terminal 8.

[0073] In this embodiment, by setting a preamplifier 7, the weak pulsating pressure signal collected by the pressure sensor 4 can be converted into a voltage or current signal with a high signal strength within the housing 6, thereby improving the anti-interference capability of the collected signal. That is, at the first moment when the pulsating pressure signal leaves the pressure sensor 4, the preamplifier 7 can amplify it into a strong signal at the volt level, thereby improving the signal-to-noise ratio and ensuring that the tiny pulsating pressure can be clearly identified.

[0074] Furthermore, the preamplifier 7 features high input impedance (for accurate reading of the pressure sensor 4 signal without causing load) and low output impedance (allowing for driving long cables and resisting interference), enabling preliminary filtering and conditioning of pulsating pressure signals, further ensuring the accuracy and reliability of the complex intelligent analysis algorithms in the backend. (See also...) Figure 3 and Figure 5 In an optional embodiment of the present invention, an underwater wet-plug electrical connector 24 is provided on the mounting base 2. One end of the underwater wet-plug electrical connector 24 is connected to the signal cable 5, and the other end is snapped into the cable adapter terminal 8.

[0075] Here, the underwater wet-plug electrical connector 24 can be a standard interface, and the underwater wet-plug electrical connector 24 is compatible with the cable adapter terminal 8, enabling plug-and-play operation of the pressure sensor 4. Furthermore, the underwater wet-plug electrical connector 24 allows divers or remotely operated vehicles (ROVs) to directly plug and unplug the pressure sensor 4 underwater, enabling repair and replacement of the pressure sensor 4 without docking, thereby reducing maintenance costs. In addition, the standardized interface of the underwater wet-plug electrical connector 24 provides a physical basis for the future integration of other types of sensors (such as acoustic and temperature sensors) into the measuring device, further expanding the functionality of the measuring device.

[0076] The measuring device provided in the above embodiments of the present invention, through its modular and detachable connection design, enables the pressure sensor to be completely recycled and reused, thereby significantly reducing the cost of pressure monitoring; by setting a preamplifier, the signal-to-noise ratio of the monitored pulsating pressure signal is improved, ensuring that minute pulsating pressures can be clearly identified, thereby ensuring the accuracy of data monitoring and further ensuring the reliability of complex intelligent data analysis and processing in the backend.

[0077] like Figure 9 As shown, embodiments of the present invention also provide a method for monitoring ship navigation status based on ship propeller pulsation pressure, comprising the following steps:

[0078] Step 11: Within a preset time period, acquire the propeller pulsation pressure signal and the operating parameters of the ship's navigation system during navigation. The pulsation pressure signal is obtained by monitoring the ship propeller pulsation pressure measurement device provided in the above embodiment. The operating parameters include ship speed, acceleration, rudder angle, engine speed and ship draft.

[0079] Step 12: Based on the pulsating pressure signal and operating parameters, determine the multidimensional feature vector of the ship during navigation within a preset time period. The multidimensional feature vector includes multiple feature values.

[0080] Step 13: Based on the multidimensional feature vector, determine the target navigation events that occur when the ship is sailing within a preset time period; the target navigation events include cavitation events, steering events, and emergency stop events.

[0081] In this embodiment, by precisely aligning data such as pulsating pressure signals and operating parameters on a unified time axis, a related multidimensional feature vector is constructed. Based on the multidimensional feature vector, various navigation events generated during ship navigation are identified, classified, and warned, providing a direct basis for optimizing ship navigation operations. At the same time, it solves the multidimensional contradictions of traditional methods in terms of real-time performance, accuracy, economy, and scalability, providing data support and theoretical basis for the intelligent management and safety assurance of ship propulsion systems.

[0082] In an optional embodiment of the present invention, after acquiring the pulsating pressure signal and operating parameters, the two types of parameters are first preprocessed to provide high-quality input data for subsequent processing, thereby ensuring the accuracy of the subsequent processing. Specifically, the preprocessing process may include the following steps:

[0083] Step 21, Data Cleaning

[0084] Outlier handling: Use statistical methods (such as the 3σ principle) to detect and remove outliers;

[0085] Missing value handling: For data with transient missing values, use linear interpolation or forward filling; for data with long-term missing values, mark it as an invalid data segment.

[0086] Step 22, Data Synchronization and Alignment

[0087] Uniform timestamps: Use GPS time or network synchronization protocols (such as PTP) to stamp each data point with a timestamp accurate to the millisecond level;

[0088] Data resampling: interpolating low-frequency data (such as engine speed in operating parameters) to the timestamp of high-frequency data (such as pulsating pressure signals), or reducing the sampling frequency of high-frequency data to be consistent with the sampling frequency of low-frequency data.

[0089] Step 23, Noise Reduction Processing

[0090] Pulsating pressure signal: Apply a bandpass filter to retain the frequency band related to the propeller blade frequency (e.g., 0.5 times the blade frequency to 10 times the blade frequency) and filter out low-frequency wave interference and high-frequency electronic noise;

[0091] Operating parameters: Use a low-pass filter or moving average to smooth high-frequency fluctuations and extract trend components.

[0092] In an optional embodiment of the present invention, step 12 above may include:

[0093] Step 121: Extract time-domain features, frequency-domain features, and time-frequency features from the pulsating pressure signal to obtain at least one pulsating pressure feature value of the pulsating pressure signal;

[0094] Here, the time-domain features of the pulsating pressure signal are extracted, specifically by calculating the peak value, root mean square value, impulse factor, waveform factor, etc. of each frame of data.

[0095] Extracting the frequency domain features of the pulsating pressure signal specifically includes: power spectrum calculation (performing a fast Fourier transform on each frame of data to estimate the power spectral density), feature frequency extraction (identifying the amplitude of the leaf frequency and its harmonics, such as 2nd leaf frequency, 3rd leaf frequency, etc.), frequency band energy analysis (calculating the energy proportion of a specific frequency band, such as narrow band near the leaf frequency and high-frequency broadband), and spectral statistics (calculating the spectral centroid and spectral entropy, where the spectral centroid is used to reflect the center of energy distribution and the spectral entropy is used to reflect the complexity of the spectral lines).

[0096] The time-frequency characteristics of the pulsating pressure signal are extracted, specifically by using short-time Fourier transform to analyze the variation of the spectrum with time (as the propeller rotation phase).

[0097] Step 122: Extract features from the operation parameters to obtain at least one operation feature value of the operation parameters;

[0098] Here, feature extraction is performed on the operating parameters. Specifically, based on each parameter in the operating parameters, the corresponding instantaneous values ​​(average engine speed, rudder angle, speed, etc. corresponding to each frame), rate of change features (first derivatives of the rate of change of speed (acceleration), rate of change of rudder angle, etc.), and derived indices (load coefficient (power / speed), advance coefficient, etc. characterizing the propeller's working state).

[0099] Step 123: Based on at least one pulsating pressure characteristic value and at least one operational characteristic value, determine the composite characteristic value of the ship during navigation within a preset time period;

[0100] Here, the composite characteristic value can be the comprehensive cavitation index, which establishes a causal relationship between each parameter and the principle of cavitation generation, thereby facilitating subsequent judgment on whether a ship has experienced a cavitation event.

[0101] Here, the blade frequency amplitude in the pulsating pressure characteristic value can be correlated with the engine speed in the operating characteristic value to obtain the normalized blade frequency pressure A (characterizing the degree of deviation of the propeller's basic pressure pulsation from its theoretical or historical healthy state under specific instantaneous operating conditions); the spectral change in the pulsating pressure characteristic value can be correlated with the acceleration in the operating characteristic value to obtain the acceleration-high frequency response coefficient B (characterizing the coupling relationship between the dynamic drastic changes in the propeller's operating state (rapid acceleration, high maneuvering) and the surge in high-frequency broadband noise energy, which is key to capturing transient cavitation and cloud cavitation); the ship's draft in the operating characteristic value can be correlated with the engine speed to obtain the environmental sensitivity factor C (quantifying the static risk coefficient of the ship's navigation environment in reducing the threshold for cavitation occurrence and aggravating the severity of cavitation); further, the normalized blade frequency pressure, acceleration-high frequency response coefficient, and environmental sensitivity factor are weighted to obtain the comprehensive cavitation index.

[0102] Preferably, the comprehensive cavitation index D can be calculated using the following formula:

[0103]

[0104] in, , , These represent the preset weights; normalized blade frequency pressure. Acceleration-High Frequency Response Coefficient Environmental sensitive factors .

[0105] Step 123: Determine a multidimensional feature vector based on the pulsating pressure signal, operating parameters, at least one pulsating pressure feature value, at least one operating feature value, and composite feature value.

[0106] Here, the initially obtained pulsating pressure signal, operating parameters, and multiple feature values ​​(pulsating pressure feature value, operating feature value, and composite feature value) are combined to obtain a multidimensional feature vector containing multidimensional data, which facilitates subsequent event discrimination.

[0107] In an optional embodiment of the present invention, step 13 above may include:

[0108] Step 131: When the comprehensive cavitation index in the multidimensional feature vector is greater than the cavitation index threshold, the rate of change of rotation speed in the multidimensional feature vector is greater than the rate of change of rotation speed, and the shallow water factor in the multidimensional feature vector is less than the shallow water factor threshold, it is determined that a cavitation event has occurred when the ship is sailing within a preset time period.

[0109] Step 132: When the rate of change of rudder angle in the multidimensional feature vector is greater than the threshold of the rate of change of rudder angle and the absolute value of rudder angle in the multidimensional feature vector is greater than the threshold of rudder angle, it is determined that the ship has experienced a rudder turning event during navigation within a preset time period.

[0110] Step 133: When the rate of change of rotational speed in the multidimensional feature vector is less than the threshold of the rate of change of rotational speed, it is determined that an emergency stop event has occurred during the ship's navigation within a preset time period.

[0111] When judging each navigation event, the judgment thresholds can be dynamically adjusted according to the ship type, loading status, sea state, etc. At the same time, each navigation event is required to meet the conditions for at least 3 consecutive data frames (e.g., 3 seconds) before it is confirmed as a valid navigation event, and the corresponding navigation event start time, trigger feature value and other metadata are recorded.

[0112] In an optional embodiment of the present invention, based on steps 11 to 13 described above, the invention may further include:

[0113] Step 14: Based on the target navigation event, determine the target monitoring mode of the measuring device and the target sampling frequency of the ship's navigation system, and output the monitoring data under the target monitoring mode and the target sampling frequency; the monitoring mode of the measuring device includes background monitoring mode and fine capture mode, and the sampling frequency of the ship's navigation system includes a first preset sampling frequency and a second preset sampling frequency, wherein the first preset sampling frequency is less than the second preset sampling frequency.

[0114] Here, the background monitoring mode is the default monitoring mode, which is the operating mode of the measuring device when no navigation events occur. After determining that a corresponding target navigation event has occurred on the current vessel, the operating mode of the measuring device is switched, and the sampling frequency of the ship's navigation system is switched, seamlessly switching from the background monitoring mode to the fine capture mode to ensure that the starting point of the navigation event is completely captured. It should be noted that the operating mode of the measuring device is the fine capture mode under all three target navigation events. In the fine capture mode, the navigation characteristics of the target navigation event are continuously monitored, and when the navigation characteristics return to the normal range, the operating mode of the measuring device is switched back to the background monitoring mode.

[0115] Here, in background monitoring mode, the measuring device acquires pulsating pressure data at a lower sampling rate (e.g., 1kHz) and uses a high compression algorithm (e.g., wavelet-based lossy compression) to store the data, significantly reducing storage requirements and power consumption. Navigation control data is recorded at a low frequency. In fine monitoring mode, the measuring device acquires pulsating pressure data at a high sampling rate (e.g., 10kHz) and uses lossless compression or low compression rate storage to ensure high data fidelity. Navigation control data is recorded synchronously at a high frequency and tagged with events. Furthermore, in different operating modes, the measuring device can package and store the corresponding monitored pulsating pressure signals according to the current operating mode. In background monitoring mode, the measuring device can use a circular buffer storage mode to allow older data to be automatically overwritten, ensuring the integrity of data boundaries corresponding to navigation events.

[0116] The measuring device and the method for monitoring ship navigation status based on the pulsating pressure signal measured by the measuring device provided by the embodiments of the present invention reduce the cost of traditional pressure monitoring and improve the accuracy of pulsating pressure signal monitoring. On the other hand, based on the fusion and intelligent analysis and judgment of pulsating pressure signal and operating parameters, it solves the multi-dimensional contradictions of traditional methods in terms of real-time performance, accuracy, economy and scalability, and provides a practical and feasible technical path for the intelligent management and safety assurance of ship propulsion systems.

[0117] like Figure 10 As shown, embodiments of the present invention also provide an electronic device 50, comprising: a memory 51 for storing one or more computer programs; and one or more processors 52 for executing the one or more computer programs. When the computer programs are run by the processors, they execute the ship navigation status monitoring method based on ship propeller pulsation pressure provided in the above embodiments. All implementations in the above method embodiments are applicable to this embodiment and can achieve the same technical effects. The electronic device 50 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components, their connections and relationships, and their functions shown in this invention are merely examples and are not intended to limit the implementation of the invention described and / or claimed herein.

[0118] like Figure 11As shown, electronic device 50 is a computing device or computer system, which may include CPU 501 (computing unit), which can perform various appropriate actions and processes according to a computer program stored in ROM 502 (read-only memory) or a computer program loaded from storage unit 508 into random access RAM 503 (memory). RAM 503 may also store various programs and data required for the operation of device 500. CPU 501, ROM 502, and RAM 503 are interconnected via bus 504. I / O interface 505 (input / output interface) is also connected to bus 504.

[0119] Multiple components in electronic device 500 are connected to I / O interface 505, including: input unit 506, such as keyboard, mouse, etc.; output unit 507, such as various types of monitors, speakers, etc.; storage unit 508, such as disk, optical disk, etc.; and communication unit 509, such as network card, modem, wireless transceiver, etc. Communication unit 509 allows device 500 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0120] CPU 501 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of CPU 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. CPU 501 performs the various methods and processes described above. For example, in some embodiments, a ship navigation status monitoring method based on ship propeller pulsation pressure can be implemented as a computer software program tangibly contained in a computer-readable storage medium, such as storage unit 508. In some embodiments, part or all of the computer program can be loaded and / or installed on device 500 via ROM 502 and / or communication unit 509. When the computer program is loaded into RAM 503 and executed by CPU 501, one or more steps of the ship navigation status monitoring method based on ship propeller pulsation pressure described above can be performed. Alternatively, in other embodiments, CPU 501 may be configured by any other suitable means (e.g., by means of firmware) to perform a ship navigation status monitoring method based on ship propeller pulsation pressure.

[0121] Embodiments of the present invention also provide a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method for monitoring ship navigation status based on ship propeller pulsation pressure provided in the above embodiments. All implementations in the above method embodiments are applicable to this embodiment and can achieve the same technical effects.

[0122] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0123] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0124] In the embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0125] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0126] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0127] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

[0128] Furthermore, it should be noted that in the apparatus and method of the present invention, it is obvious that the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalent solutions of the present invention. Moreover, the steps performing the above series of processes can naturally be executed in the order described, but are not necessarily required to be executed in chronological order; some steps can be executed in parallel or independently of each other. Those skilled in the art will understand that all or any step or component of the method and apparatus of the present invention can be implemented in any computing device (including processors, storage media, etc.) or network of computing devices, in hardware, firmware, software, or a combination thereof. This is something that those skilled in the art can achieve by using their basic programming skills after reading the description of the present invention.

[0129] Therefore, the object of the present invention can also be achieved by running a program or a set of programs on any computing device. The computing device can be a known general-purpose device. Therefore, the object of the present invention can also be achieved simply by providing a program product containing program code for implementing the method or apparatus. That is, such a program product also constitutes the present invention, and the storage medium storing such a program product also constitutes the present invention. Obviously, the storage medium can be any known storage medium or any storage medium developed in the future. It should also be noted that in the apparatus and method of the present invention, it is obvious that the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalent to the present invention. Furthermore, the steps for performing the above series of processes can naturally be performed in the order described, but are not necessarily required to be performed in chronological order. Some steps can be performed in parallel or independently of each other.

[0130] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A device for measuring the pulsating pressure of a ship propeller, characterized in that, include: Mounting base (2), one end of which is fixed to the preset monitoring point on the outer plate (1) of the ship; A quick-connect component (3) is provided at the other end of the mounting base (2). A pressure sensor (4) is installed at one end of the quick-connect component (3). The other end of the quick-connect component (3) can be snapped and fixed to the other end of the mounting base (2) to realize the detachable connection between the pressure sensor (4) and the mounting base (2). The pressure sensor (4) is connected to the central control system through a signal cable (5) embedded in the mounting base (2) to monitor the pulsating pressure signal of the ship propeller in real time. as well as The outer shell (6) is fitted over the pressure sensor (4), and one end of the outer shell (6) is fixedly connected to one end of the quick-connect assembly (3).

2. The measuring device for ship propeller pulsation pressure according to claim 1, characterized in that, The quick connection component (3) includes: The first flange (31) is fitted onto one end of the outer shell (6), and the first flange (31) has a plurality of first bolt holes; The second flange (32) is disposed opposite to the first flange (31), and the second flange (32) has a plurality of second threaded holes opposite to the first threaded holes; and Multiple locking lugs (33) are evenly distributed on the other end of the second flange (32) so as to be snapped and fixed to the other end of the mounting base (2).

3. The measuring device for ship propeller pulsation pressure according to claim 2, characterized in that, The mounting base (2) is provided with multiple guide structures at the other end. The multiple guide structures are evenly distributed at the other end of the mounting base (2). The guide structures correspond one-to-one with the locking lugs (33) and can be snapped and fixed to the locking lugs (33).

4. The measuring device for ship propeller pulsation pressure according to claim 3, characterized in that, Each guide structure includes: A guide groove (21) is provided at the other end of the mounting base (2), and the shape of the guide groove (21) matches the shape of the end of the locking lug (33); A limiting block (22) is disposed in the guide groove (21) and located at one end of the guide groove (21); A locking pin (23) is disposed on one side of the guide groove (21), with one end of the locking pin (23) located inside the guide groove (21) and the other end located outside the guide groove (21); and An elastic element is disposed between the guide groove (21) and the other end of the locking pin (23), and sleeved on the outside of the other end of the locking pin (23); when the locking lug (33) is inserted and moves along the guide groove (21) to the position of the limiting block (22), the locking pin (23) is pressed to squeeze the elastic element, and under the elastic action of the elastic element, one end of the locking pin (23) is engaged and fixed with the end of the locking lug (33).

5. The measuring device for ship propeller pulsation pressure according to claim 1, characterized in that, Also includes: A preamplifier (7) is disposed inside the housing (6). One end of the preamplifier (7) is connected to the pressure sensor (4) for communication, and the other end of the preamplifier (7) is connected to the signal cable (5) through a cable adapter terminal (8).

6. The measuring device for ship propeller pulsation pressure according to claim 5, characterized in that, The outer casing (6) is configured as a streamlined airflow shield shape, and the surface of the outer casing (6) is coated with an anti-fouling coating; and / or The mounting base (2) is provided with an underwater wet-plug electrical connector (24), one end of which is connected to the signal cable (5), and the other end is snapped into the cable adapter terminal (8).

7. A method for monitoring ship navigation status based on ship propeller pulsating pressure, characterized in that, Includes the following steps: Within a preset time period, the pulsating pressure signal of the propeller and the operating parameters of the ship's navigation system are acquired during the ship's navigation process. The pulsating pressure signal is obtained by monitoring based on the ship propeller pulsating pressure measuring device according to any one of claims 1 to 6. The operating parameters include the ship's navigation speed, acceleration, rudder angle, engine speed, and ship's draft. Based on the pulsating pressure signal and the operating parameters, a multidimensional feature vector is determined when the ship is sailing within a preset time period. The multidimensional feature vector includes multiple feature values. Based on the multidimensional feature vector, target navigation events that occur when the ship is sailing within a preset time period are determined; the target navigation events include cavitation events, steering events, and emergency stop events.

8. The method for monitoring ship navigation status based on ship propeller pulsating pressure according to claim 7, characterized in that, Based on the pulsating pressure signal and the operating parameters, a multi-dimensional feature vector is determined for the ship's navigation within a preset time period, including: The pulsating pressure signal is subjected to time-domain features, frequency-domain features, and time-frequency features extraction to obtain at least one pulsating pressure feature value of the pulsating pressure signal; Feature extraction is performed on the operation parameters to obtain at least one operation feature value of the operation parameters; Based on at least one of the pulsating pressure characteristic values ​​and at least one of the operational characteristic values, determine the composite characteristic value of the ship during navigation within a preset time period; The multidimensional feature vector is determined based on the pulsating pressure signal, the operating parameters, at least one of the pulsating pressure feature values, at least one of the operating feature values, and the composite feature value.

9. The method for monitoring ship navigation status based on ship propeller pulsating pressure according to claim 7, characterized in that, Based on the multidimensional feature vector, target navigation events occurring during a ship's navigation within a preset time period are determined, including: When the comprehensive cavitation index in the multidimensional feature vector is greater than the cavitation index threshold, the rate of change of rotation speed in the multidimensional feature vector is greater than the rate of change of rotation speed, and the shallow water factor in the multidimensional feature vector is less than the shallow water factor threshold, it is determined that a cavitation event has occurred during the ship's navigation within a preset time period. When the rate of change of rudder angle in the multidimensional feature vector is greater than the threshold of the rate of change of rudder angle and the absolute value of the rudder angle in the multidimensional feature vector is greater than the threshold of the rudder angle, it is determined that the ship has experienced a rudder turning event while sailing within a preset time period. When the rate of change of rotational speed in the multidimensional feature vector is less than the rate of change of rotational speed threshold, it is determined that the ship has experienced an emergency stop event while sailing within a preset time period.

10. The method for monitoring ship navigation status based on ship propeller pulsating pressure according to claim 7, characterized in that, Also includes: Based on the target navigation event, the target monitoring mode of the measuring device and the target sampling frequency of the ship control system are determined, and the monitoring data under the target monitoring mode and the target sampling frequency are output; the monitoring mode of the measuring device includes a background monitoring mode and a fine capture mode, and the sampling frequency of the ship control system includes a first preset sampling frequency and a second preset sampling frequency, wherein the first preset sampling frequency is less than the second preset sampling frequency.

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