Shipborne temperature-salt towing data space-time correction method and system based on dynamic positioning

Abstract

The invention provides a shipborne temperature and salt drag data space-time correction method and system based on dynamic positioning, and the method comprises the steps: collecting drag chain attitude data and ship maneuvering data in real time, and obtaining an initial three-dimensional offset estimation value; obtaining corrected drag chain attitude data based on the initial three-dimensional offset estimation value and the marine environment interference information; if the corrected drag chain attitude data shows that the position deviation parameter exceeds a preset deviation threshold value, ship maneuvering data are corrected, and real-time space positioning coordinates of the drag chain are obtained; on the basis of the real-time space positioning coordinates, correcting a ship-borne temperature and salt dragging data acquisition time sequence to obtain matched geographical attribution information; and if the matched geographical affiliation information and the preset initial geographical affiliation data are misplaced, the dynamic deviation parameter is adjusted, and a space-time synchronization correction value is obtained. According to the method, a dynamic positioning technology is utilized, the space-time error of the shipborne thermohaline drag chain data is corrected in real time, the space-time consistency of the data is ensured, and the space-time resolution of the thermohaline data is improved.

Description

Technical Field

[0001] This invention belongs to the field of data processing technology, specifically relating to a method and system for spatiotemporal correction of shipborne temperature and salinity towing data based on dynamic positioning. Background Technology

[0002] Marine environmental monitoring is a crucial foundation for ensuring the development of marine resources, environmental protection, and climate research. Especially against the backdrop of global climate change and marine ecosystem protection, acquiring high-precision ocean temperature and salinity data is paramount. Temperature and salinity data reflect the temperature and salinity characteristics of seawater, directly impacting the accuracy of ocean circulation, ecosystems, and climate models. However, shipborne towed temperature and salinity systems, as a commonly used data acquisition method, suffer from data quality constraints imposed by various complex marine environmental factors. Therefore, it is urgent to address the accuracy issues of spatial positioning and temporal synchronization to meet the demands of high-precision marine monitoring.

[0003] Existing methods for processing CTD data primarily rely on ship navigation information and simple towed body position estimation. However, these methods often overlook the complex and variable factors affecting the marine environment. For example, traditional methods typically assume a fixed relative position between the towed body and the ship, failing to adequately account for the interference of dynamic factors such as ocean currents, waves, and ship maneuvers on the towed body's position. This assumption leads to significant deviations in the geographic coordinates of data collection points, especially under complex sea conditions, where the deviations can be further amplified, affecting the reliability of the data and the accuracy of subsequent analysis. In shipborne CTD systems, the actual position of the towed body is significantly affected by changes in the attitude of the tow cable. Under the influence of ocean currents, the tow cable undergoes three-dimensional attitude shifts, causing the towed body to deviate from its expected trajectory. For instance, when the ship turns or encounters strong lateral currents, the cable may exhibit complex bending or tilting states, creating a dynamic deviation between the actual position of the towed body and the ship's position. This deviation not only affects the accuracy of spatial positioning but also, due to the mismatch between data acquisition time and location, further leads to misalignment of time-series data. Spatial positioning deviations directly affect the geographical attribution of temperature and salinity data, while time synchronization misalignments prevent the data from accurately reflecting the instantaneous state of a particular sea area.

[0004] Therefore, how to accurately determine the three-dimensional spatial position of the towed body in real time under dynamic sea conditions, and simultaneously correct the relationship between the time and position of data acquisition, has become a key issue in improving the quality of temperature, salinity, and thermal towed data. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a method and system for spatiotemporal correction of shipborne temperature and salinity towed chain data based on dynamic positioning. The aim is to utilize dynamic positioning technology to provide high-precision positioning information, correct the spatiotemporal errors of shipborne temperature and salinity towed chain data in real time, ensure the spatiotemporal consistency of the data, and improve the spatiotemporal resolution of temperature and salinity data.

[0006] To achieve the above objectives, the present invention provides the following solution: A spatiotemporal correction method for shipborne temperature, salinity, and towing data based on dynamic positioning, the method comprising: Real-time acquisition of tow chain attitude data and ship maneuver data yields initial three-dimensional offset estimates. Based on the initial three-dimensional offset estimate and marine environmental disturbance information, the corrected towed chain attitude data is obtained; If the corrected tow chain attitude data shows that the position deviation parameter exceeds the preset deviation threshold, then the ship maneuver data is corrected. Based on the corrected ship maneuver data, the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained; Based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition to obtain matching geographic attribution information. If the matched geographic attribution information is misaligned with the preset initial geographic attribution data, the dynamic deviation parameter is iteratively adjusted to obtain the final spatiotemporal synchronization correction value, thus completing the spatiotemporal correction of the shipborne temperature and salinity towed data.

[0007] Preferably, if the corrected tow chain attitude data shows that the position deviation parameter exceeds a preset deviation threshold, then the ship maneuver data is corrected, including: Calculate the course adjustment amount and adjust the ship's yaw to compensate for the lateral deviation; If the towing chain tension is less than the preset tension threshold, the boat speed is changed to adjust the towing chain tension. The ship's turning rate is directly controlled by the PD controller.

[0008] Preferably, based on the corrected ship maneuver data, the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained, including: The corrected ship maneuver data is converted into the motion of the tow chain head, and the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained by using the finite difference method. Predict the instantaneous motion of the towing chain head using ship MRU data, and perform ship motion compensation based on real-time spatial positioning coordinates; Based on real-time ocean current data acquired through ADCP, ocean current motion compensation is performed on the real-time spatial positioning coordinates.

[0009] Preferably, based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition to obtain matching geographic attribution information, including: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ; in, ri ( t k ) is the drag chain i Geographic affiliation information for each node. t k For the sampling timestamp of shipborne temperature and salinity towing data, t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, the timestamp is later than t k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chain i Each node t j+1 Real-time spatial positioning coordinates at any given moment.

[0010] The present invention also provides a shipborne temperature and salinity towed data spatiotemporal correction system based on dynamic positioning. The system is used to implement the aforementioned method. The system includes: an initial offset estimation module, a first correction module, a correction module, a coordinate acquisition module, a matching module, and a second correction module. The initial offset estimation module is used to collect tow chain attitude data and ship maneuver data in real time to obtain the initial three-dimensional offset estimate. The first correction module is used to obtain the corrected towed chain attitude data based on the initial three-dimensional offset estimate and marine environmental disturbance information. The correction module is used to correct the ship's maneuvering data if the position deviation parameter displayed by the corrected tow chain attitude data exceeds a preset deviation threshold. The coordinate acquisition module is used to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment based on the corrected ship maneuver data. The matching module is used to correct the timing of shipborne temperature and salinity towing data acquisition based on real-time spatial positioning coordinates and a time synchronization mechanism to obtain matching geographic attribution information. The second correction module is used to iteratively adjust the dynamic deviation parameter if there is a mismatch between the matched geographic attribution information and the preset initial geographic attribution data, so as to obtain the final spatiotemporal synchronization correction value and complete the spatiotemporal correction of the shipborne temperature and salinity towing data.

[0011] Preferably, the correction module includes: a heading adjustment unit, a tension adjustment unit, and a rudder angle adjustment unit; The heading adjustment unit is used to calculate the heading adjustment amount and adjust the ship's yaw to compensate for lateral deviation; The tension adjustment unit is used to adjust the towing chain tension by changing the boat speed if the towing chain tension is less than a preset tension threshold. The rudder angle adjustment unit is used to directly control the ship's turning rate via the PD controller.

[0012] Preferably, the coordinate acquisition module includes: a coordinate acquisition unit, a first compensation unit, and a second compensation unit; The coordinate acquisition unit is used to convert the corrected ship maneuver data into the motion of the tow chain head, and to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment using the finite difference method. The first compensation unit is used to predict the instantaneous motion of the towing chain head through ship MRU data and to compensate for ship motion based on real-time spatial positioning coordinates. The second compensation unit is used to compensate for ocean current motion based on real-time ocean current data acquired by ADCP and the real-time spatial positioning coordinates.

[0013] Preferably, the matching module includes: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ; in, r i ( t k ) is the drag chain i Geographic affiliation information for each node. t k For the sampling timestamp of shipborne temperature and salinity towing data, t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, the timestamp is later than t k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chaini Each node t j+1 Real-time spatial positioning coordinates at any given moment.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a method and system for spatiotemporal correction of shipborne temperature and salinity (TCS) towed data based on dynamic positioning. By dynamically adjusting the ship's motion through real-time feedback of ship maneuvering data and towed chain attitude data, the lateral offset of the towed chain is reduced. The towed chain is discretized using the finite difference method, and the forces on each node are calculated using a hydrodynamic model, improving the three-dimensional spatial positioning accuracy. Real-time ocean current measurement using ADCP, combined with ship MRU data to quantify wind and wave interference, and environmental data fusion using Kalman filtering improves anti-interference capability. Dynamic compensation of real-time spatial positioning coordinates, combined with linear interpolation to match TCS sampling times, and iterative optimization of timestamps achieve high-precision time synchronization. The system robustness is improved through multi-source data fusion from IMU, tension sensor, depth sensor, ADCP, and MRU. Compared with traditional towed data correction techniques, this invention, through innovative methods such as dynamic closed-loop control, multi-source data fusion, and spatiotemporal synchronization optimization, significantly improves the positioning accuracy, anti-interference capability, and spatiotemporal resolution of shipborne TCS towed data. Attached Figure Description

[0015] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a shipborne temperature and salinity towing data spatiotemporal correction method based on dynamic positioning, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a shipborne temperature and salinity towing data spatiotemporal correction system based on dynamic positioning, according to an embodiment of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Example 1 like Figure 1 As shown, this invention provides a spatiotemporal correction method for shipborne temperature and salinity towing data based on dynamic positioning, comprising: Real-time acquisition of tow chain attitude data and ship maneuver data yields initial three-dimensional offset estimates. Based on the initial three-dimensional offset estimate and marine environmental disturbance information, the corrected towed chain attitude data is obtained; If the corrected tow chain attitude data shows that the position deviation parameter exceeds the preset deviation threshold, then the ship maneuver data is corrected. Based on the corrected ship maneuver data, the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained; Based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition to obtain matching geographic attribution information. If the matched geographic attribution information is misaligned with the preset initial geographic attribution data, the dynamic deviation parameter is iteratively adjusted to obtain the final spatiotemporal synchronization correction value, thus completing the spatiotemporal correction of the shipborne temperature and salinity towed data.

[0020] Furthermore, the specific implementation process of this invention is as follows: Attitude sensors are deployed on the tow chain, such as inertial measurement units (IMUs) at equal intervals along the tow chain, tension sensors at the connection between the tow chain and the ship, and depth sensors at key nodes of the tow chain. Attitude sensors are used to collect tow chain attitude data in real time. The tow chain attitude data includes: real-time pitch angle, roll angle, yaw angle, angular velocity, linear acceleration, tow chain tension amplitude and direction, and real-time depth information.

[0021] Ship navigation data such as position (latitude and longitude), speed (SOG), and heading (COG) are obtained by using the ship navigation system. Ship control data such as rudder angle, rudder speed, and propeller or thruster speed are obtained by using the ship control system. Based on the six-degree-of-freedom (6-DoF) dynamic equations of the ship, the ship navigation data and the ship control data are fused to obtain ship maneuver data.

[0022] Preprocessing is performed on the tow chain attitude data and ship maneuver data to obtain denoised tow chain attitude data and ship maneuver data. Using the denoised tow chain attitude data and ship maneuver data, the initial three-dimensional offset estimate is obtained.

[0023] Marine environmental disturbance information includes ocean current influencing factors and wind and wave interference factors. The ocean current influencing factors are obtained by measuring the current velocity and direction at different water depths in real time using a shipborne acoustic Doppler current profiler (ADCP). The forced displacement of the towing chain head is calculated using ship MRU data (roll / pitch / heave) to obtain the wind and wave interference factors.

[0024] By quantifying the influencing factors of ocean currents and wave interference through fluid dynamics and ship dynamics models, marine environmental interference data is obtained. The Kalman filter algorithm is then used to fuse the initial three-dimensional offset estimate and the marine environmental interference data to obtain the corrected towed chain attitude data.

[0025] Based on the corrected drag chain attitude data, the position deviation parameters are obtained: ; in, δ p For position deviation parameters, ( X 校正 , Y 校正 ) represents the corrected planar coordinates of the drag chain. X 预期 , Y 预期 ) represents the planar coordinates of the preset drag path.

[0026] If the position deviation parameter exceeds the preset deviation threshold, the ship's maneuver data is corrected, including: Calculate heading adjustment Adjust the ship's yaw to compensate for lateral deviation; ; in, X 偏差 This is the lateral coordinate deviation. Y 偏差 This represents the longitudinal coordinate deviation. A maximum correction range is preset (e.g., ±10°) to prevent the drag chain from getting tangled during sharp turns.

[0027] If the towing chain tension is less than the preset tension threshold, the boat speed is changed to adjust the towing chain tension. ; in, v new It's the changed ship speed. v current That was the ship's speed before the change. K T It is a proportionality coefficient. T min It is a preset tension threshold. T It is the tension of the drag chain.

[0028] Directly control the ship's turning rate via the PD controller: ; in, δ rudder It is the ship's turning rate.K p and K d These are all control coefficients. t It's time.

[0029] The corrected ship maneuvering data is converted into the motion of the tow chain head. The tow chain is discretized into multiple segments using the finite difference method. For each segment, new coordinates of each node are obtained based on the resultant force (current force + gravity + inertial force) and tension acting on the head after the corrected motion, thus obtaining the real-time spatial positioning coordinates of the tow chain in the marine environment. Dynamic compensation is then applied to these real-time spatial positioning coordinates: firstly, the instantaneous motion of the tow chain head is predicted using ship MRU data, while simultaneously using an ARIMA model or LSTM network to predict the ship's motion over a certain period, compensating for ship motion in the real-time spatial positioning coordinates; secondly, ocean current data is acquired in real-time based on ADCP, and ocean current motion compensation is applied to the real-time spatial positioning coordinates.

[0030] R ′= R + R c + R d ; in, R ′ represents the real-time spatial positioning coordinates after dynamic compensation. R The real-time spatial positioning coordinates before dynamic compensation. R c For ship motion compensation coordinates, R d The coordinates are used to compensate for ocean current movement.

[0031] Based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition, resulting in matching geographic attribution information, including: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ; in, r i ( t k (This refers to the sampling timestamps for shipborne temperature and salinity towing data.) t k Aligned drag chain i The interpolated coordinates of each node represent the matched geographic attribution information. t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, the timestamp is later thant k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chain i Each node t j+1 Real-time spatial positioning coordinates at any given moment.

[0032] If the matched geographic attribution information deviates from the preset initial geographic attribution data, the deviation value is calculated through a deviation detection mechanism. The deviation detection mechanism can be implemented by comparing the spatial coordinate differences between the matched geographic attribution information and the preset initial geographic attribution data.

[0033] A gradient descent algorithm is used to adjust the dynamic deviation parameters, with the deviation value as the objective of the loss function. The parameters are iteratively adjusted to minimize the deviation, and the gradient descent algorithm adjusts the coordinate offset through multiple iterations. Furthermore, based on timestamp-based deviation analysis, an iterative optimization method is used to calculate the time synchronization correction value, adjust the timestamp, and obtain the final spatiotemporal synchronization correction value. Based on the final spatiotemporal synchronization correction value, the synchronized and optimized geographic attribution information is obtained.

[0034] In summary, this invention provides a spatiotemporal correction method for shipborne temperature and salinity (TCS) towed data based on dynamic positioning. By dynamically adjusting the ship's motion through real-time feedback of ship maneuvering data and tow chain attitude data, the lateral offset of the tow chain is reduced. The tow chain is discretized using the finite difference method, and the forces on each node are calculated using a hydrodynamic model, improving the three-dimensional spatial positioning accuracy. Real-time ocean current measurement using ADCP, combined with ship MRU data to quantify wind and wave interference, and environmental data fusion using Kalman filtering improve anti-interference capability. Dynamic compensation of real-time spatial positioning coordinates, combined with linear interpolation to match TCS sampling times, and iterative optimization of timestamps achieve high-precision time synchronization. The fusion of multi-source data from IMU, tension sensor, depth sensor, ADCP, and MRU improves system robustness. Compared with traditional towed data correction techniques, this invention, through innovative methods such as dynamic closed-loop control, multi-source data fusion, and spatiotemporal synchronization optimization, significantly improves the positioning accuracy, anti-interference capability, and spatiotemporal resolution of shipborne TCS towed data.

[0035] Example 2 like Figure 2As shown, based on the same inventive concept, the present invention also provides a shipborne temperature and salinity towing data spatiotemporal correction system based on dynamic positioning, used to implement the method described in the foregoing embodiments. The system includes: an initial offset estimation module, a first correction module, a correction module, a coordinate acquisition module, a matching module, and a second correction module. The initial offset estimation module is used to collect tow chain attitude data and ship maneuver data in real time to obtain the initial three-dimensional offset estimate. The first correction module is used to obtain the corrected towed chain attitude data based on the initial three-dimensional offset estimate and marine environmental disturbance information. The correction module is used to correct the ship's maneuvering data if the position deviation parameter displayed by the corrected tow chain attitude data exceeds a preset deviation threshold. The coordinate acquisition module is used to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment based on the corrected ship maneuver data. The matching module is used to correct the timing of shipborne temperature and salinity towing data acquisition based on real-time spatial positioning coordinates and a time synchronization mechanism to obtain matching geographic attribution information. The second correction module is used to iteratively adjust the dynamic deviation parameter if there is a mismatch between the matched geographic attribution information and the preset initial geographic attribution data, so as to obtain the final spatiotemporal synchronization correction value and complete the spatiotemporal correction of the shipborne temperature and salinity towing data.

[0036] Furthermore, the correction module includes: a heading adjustment unit, a tension adjustment unit, and a rudder angle adjustment unit; The heading adjustment unit is used to calculate the heading adjustment amount and adjust the ship's yaw to compensate for lateral deviation; The tension adjustment unit is used to adjust the towing chain tension by changing the boat speed if the towing chain tension is less than a preset tension threshold. The rudder angle adjustment unit is used to directly control the ship's turning rate via the PD controller.

[0037] Furthermore, the coordinate acquisition module includes: a coordinate acquisition unit, a first compensation unit, and a second compensation unit; The coordinate acquisition unit is used to convert the corrected ship maneuver data into the motion of the tow chain head, and to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment using the finite difference method. The first compensation unit is used to predict the instantaneous motion of the towing chain head through ship MRU data and to compensate for ship motion based on real-time spatial positioning coordinates. The second compensation unit is used to compensate for ocean current motion based on real-time ocean current data acquired by ADCP and the real-time spatial positioning coordinates.

[0038] Furthermore, the matching module includes: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ; in, r i ( t k ) is the drag chain i Geographic affiliation information for each node. t k For the sampling timestamp of shipborne temperature and salinity towing data, t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, the timestamp is later than t k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chain i Each node t j+1 Real-time spatial positioning coordinates at any given moment.

[0039] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A spatiotemporal correction method for shipborne temperature and salinity towing data based on dynamic positioning, characterized in that, The method includes: Real-time acquisition of tow chain attitude data and ship maneuver data yields initial three-dimensional offset estimates. Based on the initial three-dimensional offset estimate and marine environmental disturbance information, the corrected towed chain attitude data is obtained; If the corrected tow chain attitude data shows that the position deviation parameter exceeds the preset deviation threshold, then the ship maneuver data is corrected. Based on the corrected ship maneuver data, the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained; Based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition to obtain matching geographic attribution information. If the matched geographic attribution information is misaligned with the preset initial geographic attribution data, the dynamic deviation parameter is iteratively adjusted to obtain the final spatiotemporal synchronization correction value, thus completing the spatiotemporal correction of the shipborne temperature and salinity towing data.

2. The method according to claim 1, characterized in that, If the corrected tow chain attitude data shows that the position deviation parameter exceeds the preset deviation threshold, then the ship maneuver data is corrected, including: Calculate the course adjustment amount and adjust the ship's yaw to compensate for the lateral deviation; If the towing chain tension is less than the preset tension threshold, the boat speed is changed to adjust the towing chain tension. The ship's turning rate is directly controlled by the PD controller.

3. The method according to claim 1, characterized in that, Based on the corrected ship maneuver data, the real-time spatial positioning coordinates of the towed chain in the marine environment are obtained, including: The corrected ship maneuver data is converted into the motion of the tow chain head, and the real-time spatial positioning coordinates of the tow chain in the marine environment are obtained by using the finite difference method. Predict the instantaneous motion of the towing chain head using ship MRU data, and perform ship motion compensation based on real-time spatial positioning coordinates; Based on real-time ocean current data acquired through ADCP, ocean current motion compensation is performed on the real-time spatial positioning coordinates.

4. The method according to claim 1, characterized in that, Based on real-time spatial positioning coordinates, a time synchronization mechanism is used to correct the timing of shipborne temperature and salinity towing data acquisition, resulting in matching geographic attribution information, including: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ； in, r i ( t k ) is the drag chain i Geographic affiliation information for each node. t k For the sampling timestamp of shipborne temperature and salinity towing data, t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, timestamps later than t k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chain i Each node t j+1 Real-time spatial positioning coordinates at any given moment.

5. A shipborne temperature and salinity towed data spatiotemporal correction system based on dynamic positioning, the system being used to implement the method described in any one of claims 1-4, characterized in that, The system includes: an initial offset estimation module, a first correction module, a correction module, a coordinate acquisition module, a matching module, and a second correction module; The initial offset estimation module is used to collect tow chain attitude data and ship maneuver data in real time to obtain the initial three-dimensional offset estimate. The first correction module is used to obtain the corrected towed chain attitude data based on the initial three-dimensional offset estimate and marine environmental disturbance information. The correction module is used to correct the ship's maneuvering data if the position deviation parameter displayed by the corrected tow chain attitude data exceeds a preset deviation threshold. The coordinate acquisition module is used to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment based on the corrected ship maneuver data. The matching module is used to correct the timing of shipborne temperature and salinity towing data acquisition based on real-time spatial positioning coordinates and a time synchronization mechanism to obtain matching geographic attribution information. The second correction module is used to iteratively adjust the dynamic deviation parameter if there is a mismatch between the matched geographic attribution information and the preset initial geographic attribution data, so as to obtain the final spatiotemporal synchronization correction value and complete the spatiotemporal correction of the shipborne temperature and salinity towing data.

6. The system according to claim 5, characterized in that, The correction module includes: a heading adjustment unit, a tension adjustment unit, and a rudder angle adjustment unit; The heading adjustment unit is used to calculate the heading adjustment amount and adjust the ship's yaw to compensate for lateral deviation; The tension adjustment unit is used to adjust the towing chain tension by changing the boat speed if the towing chain tension is less than a preset tension threshold. The rudder angle adjustment unit is used to directly control the ship's turning rate via the PD controller.

7. The system according to claim 5, characterized in that, The coordinate acquisition module includes: a coordinate acquisition unit, a first compensation unit, and a second compensation unit; The coordinate acquisition unit is used to convert the corrected ship maneuver data into the motion of the tow chain head, and to obtain the real-time spatial positioning coordinates of the tow chain in the marine environment using the finite difference method. The first compensation unit is used to predict the instantaneous motion of the towing chain head through ship MRU data and to compensate for ship motion based on real-time spatial positioning coordinates. The second compensation unit is used to compensate for ocean current motion based on real-time ocean current data acquired by ADCP and the real-time spatial positioning coordinates.

8. The system according to claim 5, characterized in that, The matching module includes: Real-time spatial positioning coordinates are matched with temperature and salinity sampling times using linear interpolation to obtain the matched geographic attribution information: ； in, r i ( t k ) is the drag chain i Geographic affiliation information for each node. t k For the sampling timestamp of shipborne temperature and salinity towing data, t j For timestamps in the positioning system that are earlier than t k The most recent recorded time, t j+1 For the location system, timestamps later than t k The most recent recorded time, r i ( t j ) is the drag chain i Each node t j Real-time spatial positioning coordinates at any given moment. r i ( t j+1 ) is the drag chain i Each node t j+1 Real-time spatial positioning coordinates at any given moment.

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