A data analysis-based underwater sewage outlet location and investigation system and method

Abstract

A data analysis-based underwater sewage outlet location and investigation system and method are disclosed. The system includes a hull, on which are mounted a water quality detection device, a pressure acquisition device, an image acquisition device, a power unit, and an environmental sensing device. It also includes a processor. The water quality detection device includes a water quality probe that can extend downwards into the water to detect NH3-N and TP, and transmits the detection data to the processor. The pressure acquisition device detects the pressure at different depths in the water and transmits the pressure data to the processor. The image acquisition device takes photographs at different underwater depths and transmits the images to the processor. The power unit drives the hull. The environmental sensing device determines the distance between the hull and the shore, as well as the water depth, and transmits the data to the processor. A GPS module is also installed within the hull to send the hull's position information to the processor.

Description

Technical Field

[0001] This invention relates to the field of underwater sewage outlet investigation technology, and in particular to an underwater sewage outlet investigation and positioning system and method based on data analysis. Background Technology

[0002] Locating underwater sewage outlets has always been a crucial aspect of aquatic environment management, as their submerged nature makes the search challenging. Current technologies commonly employ two methods: precipitation-based investigation and water quality testing result inversion. Precipitation-based investigation involves lowering the water depth to expose the outlets, but this method is difficult to coordinate and has limited practicality. Water quality testing result inversion involves analyzing water quality trends to determine the presence of outlets, but this method suffers from high randomness, high costs, and inability to accurately pinpoint the outlets. With advancements in technology, underwater robots and other methods have been introduced to assist in the investigation.

[0003] For example, patent application CN112381369A discloses a method for inverting the location of sewage outlets based on water quality test results using a mathematical model. This method uses theoretical formulas for deduction and calculation, but the factors affecting the migration of pollutants in water bodies are complex, and the accuracy of the results is not easy to guarantee.

[0004] For example, patent application CN113741489A discloses an underwater robot and search and positioning method that has been used for tracing sewage outlets. Its search method relies on turbidity for route planning. If the water discharged from the underwater sewage outlet is cleaner than the water in the water body, the path planning mode that relies on the direction of maximum turbidity as the direction of movement has a chance of omission. Moreover, in actual water bodies with low transparency, the success rate of the method of taking pictures and identifying by underwater cameras is not high.

[0005] For example, although the patent application with publication number CN110672807A proposes to rely on unmanned ships to sample and analyze water quality to determine whether the water quality of sewage outlets exceeds the standard, the application scenario is to dynamically monitor sewage outlets that have been identified, and it is not suitable for the investigation and location of unknown sewage outlets. Summary of the Invention

[0006] The main objective of this invention is to propose a data analysis-based underwater sewage outlet investigation and location system and method to solve the aforementioned technical problems.

[0007] To achieve the above objectives, this invention proposes a data analysis-based underwater sewage outlet location and investigation system, comprising a hull equipped with a water quality detection device, a pressure acquisition device, an image acquisition device, a power unit, and an environmental sensing device; and a processor. The water quality detection device includes a water quality probe that can extend downwards into the water to detect NH3-N and TP, and transmits the detection data to the processor. The pressure acquisition device detects the pressure at different depths in the water and transmits the pressure data to the processor. The image acquisition device takes photographs at different underwater depths and transmits the images to the processor. The power unit drives the hull. The environmental sensing device determines the distance between the hull and the shore, as well as the water depth, and transmits the data to the processor. A GPS module is also installed within the hull to send the hull's location information to the processor. The system also includes a human-machine interface terminal and a remote control device. The human-machine interface terminal is connected to the processor, and the remote control device is connected to the power unit, the image acquisition device, the water quality detection device, and the pressure acquisition device.

[0008] Preferably, the pressure acquisition device includes a telescopic rod and a pressure acquisition plate disposed at the lower end of the telescopic rod; the upper end of the telescopic rod is connected to the hull; and multiple pressure sensors are evenly distributed on the pressure acquisition plate.

[0009] Preferably, the image acquisition device includes a pole, a steering rod, a lifting rod, and a waterproof camera; the pole is vertically installed on the hull, the steering rod is horizontally set, and one end of the steering rod is rotatably installed on the top of the pole, the other end of the steering rod is connected to the top of the lifting rod, and the waterproof camera is installed at the lower end of the lifting rod.

[0010] On the other hand, this invention proposes a data analysis-based method for locating and investigating underwater sewage outlets, employing the aforementioned data analysis-based underwater sewage outlet locating and investigation system, comprising:

[0011] S1: Place the ship on the water body to be studied, and move the ship in the water body according to the set inspection route;

[0012] S2: During the movement of the ship in the water, the water quality detection probe in the water quality detection device is lowered to detect the concentration of NH3-N and TP in the water at a set time step, and the detection data is transmitted to the processor. At the same time, the GPS module is used to send the coordinates of the sampling point to the processor.

[0013] S3: The processor performs real-time analysis of pollutant concentrations in the received water quality data and displays the results on the human-computer interaction terminal. The pollutant concentrations at time t are denoted as follows: ={ , The pollutant concentration detected at the previous time point, i.e., time t-1, is} , Through analysis and The relationship is such that commands are issued via remote control to control the ship's forward or backward movement;

[0014] S4: If the ship needs to move forward, repeat steps S2 and S3; if the ship needs to move backward, move the ship to the position at time t-1 and keep it stable. Execute the backward command, and mark the region between the ship's position at time t-1 and time t as the suspected region W. i ;

[0015] S5: Activate the pressure acquisition device and acquire pressure data at different depth locations, and transmit the pressure data to the processor; activate the image acquisition device, acquire images at different depth locations, and transmit them to the processor; display the acquired data on the human-computer interaction terminal;

[0016] S6: Drive the hull to move a certain distance in the direction of the position at time t, repeat step S5 until the hull moves to the position at time t to complete the profile pressure acquisition and profile image acquisition.

[0017] S7: The processor uses Kalman filtering to filter the pressure data collected in steps S5 to S6 and performs water depth calibration to establish a suspected area W. i Data E of each pressure submatrix i The suspected regions W were obtained by arranging them sequentially according to the sampling order. i The profile pressure matrix R i The processor automatically traverses all values ​​in matrix R, filters to obtain the maximum value in the matrix, marks the intersection nodes with the maximum value as the center, and uses the marked points as the location range of the sewage outlet.

[0018] S8: Determine the position of the point in the matrix and calculate the location coordinates and depth coordinates of the sewage outlet;

[0019] S9: Repeat steps S2 to S8 above to complete the search for all underwater sewage outlets in the water area.

[0020] Preferably, in step S3,

[0021] when - When ≥0:

[0022] ,

[0023] Among them: A i A threshold coefficient is added to the pollutant concentration, with a value ranging from 0.1 to 0.5.

[0024] when - When <0,

[0025] ,

[0026] Among them: B i To reduce the threshold coefficient for pollutant concentration;

[0027]

[0028] In the formula: k i The combined attenuation coefficient of NH3-N and TP. For time step.

[0029] Preferably, in step S4, the distance between the ship and the shore and the water depth are determined by the environmental sensing device on the ship. The environmental sensing device is a sonar device, which emits sonar signals and receives feedback to transmit information to the processor. The processor deduces the distance H between the ship and the shore and the seabed based on the sonar information.

[0030] Preferably, the pressure acquisition device comprises a telescopic rod body composed of multiple rod segments, with the lower end of the telescopic rod body connected to a pressure acquisition plate. Each rod segment has a length of L. The number of rod segments Nmax is determined based on the distance H between the hull and the seabed, calculated using the following formula: In step S5, when collecting pressure data at different depths, the telescopic rod is extended to lower the pressure acquisition plate into the water. The number of rod extension sections is Nmax, where Nmax = {0, 1, 2, ...}. When the number of rods is 0, the pressure acquisition plate is extended. After extension, it remains stationary for 1 minute before the pressure sensor is activated and data is collected. The data collection time is 1 minute. After data collection, the next rod is extended, and the above process is repeated until the number of extended rods equals Nmax. After data collection, the pressure acquisition plate is retracted. When Nmax = 0, only a positioning mark is made, and pressure detection is abandoned.

[0031] Preferably, the pressure acquisition plate on the pressure acquisition device has nine pressure sensors distributed in a 3×3 matrix. In step S7, after the pressure data undergoes Kalman filtering and water depth calibration, a pressure submatrix E is output. i After performing Kalman filtering, the average value is retained. Perform water depth calibration, and obtain the actual hydrodynamic pressure value after water depth calibration. The actual values ​​of the obtained hydrodynamic pressure are output to form a pressure submatrix E. i .

[0032] Preferably, the pressure submatrix is ​​3. 3 matrix The profile pressure matrix Ri is m n matrix, Where m= , n = Nmax + 1; and These represent the planar position coordinates of the ship in the waters to be investigated at time t and time t-1, respectively.

[0033] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0034] (1) This invention identifies suspected areas of underwater sewage outlets by judging the fluctuation of pollutant concentration in the water in real time. Then, it uses pressure sensors to locate the plane and elevation of the underwater sewage outlets. This overcomes the shortcomings of the previous method of relying solely on underwater cameras to take pictures and identify in water with high turbidity. The whole process is automatic and efficient. All collected and analyzed data can be transmitted to the terminal display screen. Staff can correct the behavior of the inspection boat, which greatly improves the accuracy of underwater sewage outlet investigation and location.

[0035] (2) This invention proposes a method for locating and investigating sewage outlets based on the coupled data analysis of pollutant concentration and dynamic water pressure, supplemented by sonar and underwater camera recording. This method effectively improves the accuracy of underwater sewage outlet investigation and can locate the plane position and underwater depth of the sewage outlet in one go.

[0036] (3) The present invention overcomes the drawback of the previous single underwater camera being too far from the sewage outlet and the image being unclear by using a combination of sonar and underwater camera.

[0037] (4) After the sewage outlet is located, the water quality testing instrument can be activated to achieve accurate sampling of the sewage outlet.

[0038] (5) This invention utilizes water quality testing instruments for analysis and a ship positioning system, and can also display the spatial distribution of pollutant concentrations in water. The system provided by this invention can be used for routine waterway patrols, underwater surveys, and other purposes. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be 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 the structures shown in these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the structure in which the hull and the image acquisition device cooperate in this invention;

[0041] Figure 2 This is a top view of the hull in this invention;

[0042] Figure 3 This is a schematic diagram of the pressure acquisition device in this invention;

[0043] Figure 4 This is a schematic diagram showing the connection relationship of the various devices in this method.

[0044] The following are the reference numerals: 1. Hull; 2. Water quality testing device; 3. Pressure acquisition device; 3a. Telescopic pole; 3b. Pressure acquisition plate; 3c. Pressure sensor; 4. Image acquisition device; 4a. Pole; 4b. Steering pole; 4c. Lifting pole; 4d. Waterproof camera; 5. Power unit; 6. Processor; 7. Environmental sensing device. Detailed Implementation

[0045] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0046] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0047] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0048] Referring to the accompanying drawings, this embodiment provides an underwater sewage outlet investigation and location system based on data analysis, including a hull 1. The hull 1 is equipped with a water quality detection device 2, a pressure acquisition device 3, an image acquisition device 4, a power unit 5, and an environmental sensing device 7. It also includes a processor 6. The water quality detection device 2 includes a water quality detection probe that can extend downwards into the water to detect NH3-N and TP, and transmits the detection data to the processor 6. The pressure acquisition device 3 is used to detect the pressure at different depths in the water and transmits the pressure data to the processor 6. The image acquisition device 4 is used to take pictures at different underwater depths and transmit the images to the processor 6; the power unit 5 is used to drive the hull 1 to move; the environmental sensing device 7 is used to determine the distance between the hull 1 and the shore and the water depth, and transmit the data to the processor 6; a GPS module is also installed in the hull 1 to send the position information of the hull 1 to the processor 6; it also includes a human-machine interaction terminal and a remote control device, the human-machine interaction terminal is connected to the processor 6, and the remote control device is connected to the power unit 5, the image acquisition device 4, the water quality detection device 2, and the pressure acquisition device 3 respectively.

[0049] In addition, a battery pack is installed on the hull 1 to power various electrical devices on the hull 1. The processor 6 includes a water quality analysis module for analyzing the water quality data collected by the water quality detection device 2, a data storage module for storing the water quality data, and a transmission module for transmitting the analysis results to a human-computer interaction terminal for display.

[0050] In this embodiment, the pressure acquisition device 3 includes a telescopic rod 3a and a pressure acquisition plate 3b disposed at the lower end of the telescopic rod 3a; the upper end of the telescopic rod 3a is connected to the hull 1; and multiple pressure sensors 3c are evenly distributed on the pressure acquisition plate 3b. Specifically, the pressure acquisition plate 3b is a 50×40×5cm cuboid plate, and nine pressure sensors 3c are distributed in a 3×3 matrix on the 50×40cm plane. Further, the telescopic rod 3a is composed of multiple rod segments, each segment having a length L, and the length L has various specifications such as 10, 20, and 30cm; when the pressure acquisition device 3 is not activated, the telescopic rod 3a is in a retracted state.

[0051] Combination Figure 1As shown, the image acquisition device 4 includes a pole 4a, a steering rod 4b, a lifting rod 4c, and a waterproof camera 4d. The pole 4a is vertically mounted on the hull 1, the steering rod 4b is horizontally positioned, and one end of the steering rod 4b is rotatably mounted on the top of the pole 4a. The other end of the steering rod 4b is connected to the top of the lifting rod 4c, and the waterproof camera 4d is mounted on the lower end of the lifting rod 4c. The water depth of the waterproof camera 4d is controlled by the lifting rod 4c to take pictures at different underwater depths. When the image acquisition device 4 is not activated, the lifting rod 4c is in a retracted state.

[0052] The power unit 5 includes motor-driven propellers fixed around the hull 1. The rotation of the propellers can be remotely controlled via a remote control device, thereby driving the free movement of the hull 1.

[0053] In this embodiment, the environmental sensing device 7 is a sonar device.

[0054] On the other hand, this embodiment also provides a data analysis-based method for locating and investigating underwater sewage outlets, employing the aforementioned data analysis-based underwater sewage outlet locating and investigating system, including:

[0055] S1: Place hull 1 on the water body to be studied, and hull 1 moves in the water body according to the set inspection route;

[0056] S2: During the movement of the hull 1 in the water, the water quality detection probe in the water quality detection device 2 is lowered to detect the concentration of NH3-N and TP in the water at a set time step, and the detection data is transmitted to the processor 6. At the same time, the GPS module is used to send the coordinates of the sampling point to the processor 6.

[0057] S3: Processor 6 performs real-time analysis of pollutant concentrations in the received water quality data and displays the results on the human-computer interaction terminal. The pollutant concentrations at time t are denoted as follows: ={ , The pollutant concentration detected at the previous time point, i.e., time t-1, is} , Through analysis and The relationship is such that the remote control device is used to send commands to control the ship 1 to move forward or backward; the human-machine interaction terminal can display images of pollutant concentration changes in real time, and can determine that a certain area needs further detection based on the images, and send commands through the remote control device to execute the operation.

[0058] S4: If hull 1 needs to move forward, repeat steps S2 and S3; if hull 1 needs to move backward, move hull 1 to the position at time t-1 and keep it stable. If hull 1 executes the backward command, mark the area between the position of hull 1 at time t-1 and time t as the suspected area W. i The position at time t-1 should ideally be such that the distance between the hull 1 and the shore is 0.5m. When the environmental sensing device 7 detects that the distance between the hull 1 and the shore is greater than 0.5m, the propeller of the hull 1 is activated to move the hull 1 toward the shore until the distance between the hull 1 and the shore is 0.5m. In addition, an anchoring device can be installed on the hull 1 to keep the hull 1 relatively stationary.

[0059] S5: Start the pressure acquisition device 3 and acquire pressure data at different depths, and transmit the pressure data to the processor 6; start the image acquisition device 4 and acquire images at different depths and transmit them to the processor 6; display the acquired data on the human-computer interaction terminal;

[0060] S6: Cancel anchoring, drive hull 1 to move a certain distance in the direction of the position at time t, such as 50cm. Repeat step S5 until hull 1 moves to the position at time t to complete the profile pressure acquisition and profile image acquisition. In this step, the distance between the position at time t-1 and the position at time t is... Therefore, during the process of hull component 1 moving from its position at time t-1 to its position at time t, The planar water pressure distribution data along the water depth direction is obtained on the x-scale;

[0061] S7: Processor 6 uses Kalman filtering to filter the pressure data collected in steps S5 to S6 and performs water depth calibration to establish a suspected area W. i Data E of each pressure submatrix i The suspected regions W were obtained by arranging them sequentially according to the sampling order. i The profile pressure matrix R i Processor 6 automatically traverses all values ​​in matrix R, filters to obtain the maximum value in the matrix, marks the intersection nodes with the maximum value as the center, and uses the marked points as the location range of the sewage outlet.

[0062] S8: Determine the position of the point in the matrix and calculate the location coordinates and depth coordinates of the sewage outlet;

[0063] S9: Repeat steps S2 to S8 above to complete the search for all underwater sewage outlets in the water area.

[0064] In this embodiment, in step S3, the judgment logic and execution instructions are as follows: if hull 1 executes the reverse instruction, then the region between the position of the hull at time t-1 and time t is marked as the suspected region W. i :

[0065] (1) When - When ≥0:

[0066] ,

[0067] Among them: A i A threshold coefficient is added to the pollutant concentration, with a value ranging from 0.1 to 0.5.

[0068] (2) When - When <0,

[0069] ,

[0070] Among them: B i To reduce the threshold coefficient for pollutant concentration;

[0071]

[0072] In the formula: k i The combined attenuation coefficient of NH3-N and TP. For time step.

[0073] In this embodiment, in step S4, the environmental sensing device 7 on the hull 1 is used to determine the distance between the hull 1 and the shore, as well as the water depth. The environmental sensing device 7 is a sonar device that emits sonar signals and receives feedback, transmitting the information to the processor 6. The processor 6 deduces the distance H between the hull 1 and the shore and the bottom of the water based on the sonar information. The pressure acquisition device 3 has a telescopic rod 3a composed of multiple rod segments. The lower end of the telescopic rod 3a is connected to the pressure acquisition plate 3b. The length of each rod segment is L. The number of rods Nmax is determined based on the distance H between the hull 1 and the bottom of the water, calculated using the following formula: In step S5, when collecting pressure data at different depths, the telescopic rod 3a is extended so that the pressure acquisition plate 3b descends and is immersed in the water. The number of rod extension sections is Nmax, where Nmax = {0, 1, 2, ...}. When the number of rods is 0, the pressure acquisition plate 3b is extended. After extension, it remains stationary for 1 minute before the pressure sensor is activated and data is collected. The data collection time is 1 minute. After data collection, the next rod is extended, and the above process is repeated until the number of extended rods equals Nmax. After data collection, the pressure acquisition plate 3b is retracted. When Nmax = 0, only positioning marking is performed, and pressure detection is abandoned.

[0074] In steps S5 and S6, the pressure values ​​collected by the pressure sensor are time-series pressure data within 1 minute. In step S7, the pressure data is Kalman filtered and calibrated for water depth, and then the pressure sub-matrix E is output. i After performing Kalman filtering, the average value is retained. Perform water depth calibration, and obtain the actual hydrodynamic pressure value after water depth calibration. The actual values ​​of the obtained hydrodynamic pressure are output to form a pressure submatrix E. i The pressure submatrix is ​​3. 3 matrix The profile pressure matrix Ri is m n matrix, Where m= , n = Nmax + 1. and These represent the planar position coordinates of the ship in the waters to be investigated at time t and time t-1, respectively.

[0075] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for locating underwater sewage outlets based on data analysis, characterized in that, A data analysis-based underwater sewage outlet location system is adopted, which includes a hull (1). The hull (1) is equipped with a water quality detection device (2), a pressure acquisition device (3), an image acquisition device (4), a power unit (5), and an environmental sensing device (7); it also includes a processor (6); the water quality detection device (2) includes a water quality detection probe, which can be inserted into the water to detect NH3-N and TP in the water, and transmit the detection data to the processor (6); the pressure acquisition device (3) is used to detect the pressure at different depths in the water and transmit the pressure data to the processor (6); the image acquisition device (4) is used to take pictures at different underwater depths and transmit the images. The image is transmitted to the processor (6); the power unit (5) is used to drive the hull (1) to move; the environmental sensing device (7) is used to determine the distance between the hull (1) and the shore and the water depth, and transmit the data to the processor (6); a GPS module is also provided in the hull (1) to send the location information of the hull (1) to the processor (6); it also includes a human-computer interaction terminal and a remote control device, the human-computer interaction terminal is connected to the processor (6), and the remote control device is connected to the power unit (5), the image acquisition device (4), the water quality detection device (2), and the pressure acquisition device (3) respectively; The method includes the following steps: S1: Place the hull (1) on the water body to be studied, and move the hull (1) in the water body according to the set inspection route; S2: During the movement of the hull (1) in the water body, the water quality detection probe in the water quality detection device (2) is lowered to detect the concentration of NH3-N and TP in the water body at a set time step, and the detection data is transmitted to the processor (6). At the same time, the GPS module is used to send the coordinates of the sampling point to the processor (6). S3: The processor (6) performs real-time analysis on the pollutant concentration in the received water quality data and displays it on the human-computer interaction terminal. The pollutant concentration at time t is recorded as follows: ={ , The pollutant concentration detected at the previous time point, i.e., time t-1, is} , Through analysis and The relationship is that the remote control device is used to issue commands to control the hull (1) to move forward or backward; S4: If the hull (1) needs to move forward, repeat steps S2 and S3; if the hull (1) needs to move backward, move the hull (1) to the position at time t-1 and keep it stable. If the hull (1) executes the backward command, mark the area between the position of the hull (1) at time t-1 and time t as the suspected area W. i ; S5: Start the pressure acquisition device (3) and acquire pressure data at different depths, and transmit the pressure data to the processor (6); start the image acquisition device (4) and acquire images at different depths and transmit them to the processor (6); display the acquired data on the human-computer interaction terminal; S6: Drive the hull (1) to move a certain distance in the direction of the position at time t, repeat step S5 until the hull (1) moves to the position at time t to complete the profile pressure acquisition and the profile image acquisition. S7: The processor (6) filters the pressure data collected according to steps S5 to S6 using Kalman filtering and performs water depth calibration to establish a suspected area W. i Data E of each pressure submatrix i The suspected regions W were obtained by arranging them sequentially according to the sampling order. i The profile pressure matrix R i The processor (6) automatically traverses all values ​​in matrix R and filters to obtain the maximum value in the matrix. It marks the intersection nodes with the maximum value as the center and uses the marked points as the location range of the sewage outlet. S8: Determine the position of the point in the matrix and calculate the location coordinates and depth coordinates of the sewage outlet; S9: Repeat steps S2 to S8 above to complete the search for all underwater sewage outlets in the water area.

2. The underwater sewage outlet investigation and location method based on data analysis as described in claim 1, characterized in that, The pressure acquisition device (3) includes a telescopic rod (3a) and a pressure acquisition plate (3b) disposed at the lower end of the telescopic rod (3a); the upper end of the telescopic rod (3a) is connected to the hull (1); and multiple pressure sensors (3c) are evenly distributed on the pressure acquisition plate (3b).

3. The underwater sewage outlet investigation and location method based on data analysis as described in claim 1, characterized in that, The image acquisition device (4) includes a pole (4a), a steering rod (4b), a lifting rod (4c), and a waterproof camera (4d); the pole (4a) is vertically installed on the hull (1), the steering rod (4b) is horizontally set, and one end of the steering rod (4b) is rotatably installed on the top of the pole (4a), the other end of the steering rod (4b) is connected to the top of the lifting rod (4c), and the waterproof camera (4d) is installed at the lower end of the lifting rod (4c).

4. The underwater sewage outlet investigation and location method based on data analysis as described in claim 1, characterized in that, In step S3, when - When ≥0: ， Among them: A i A threshold coefficient is added to the pollutant concentration, with a value ranging from 0.1 to 0.5; when - When <0, ， Among them: B i To reduce the threshold coefficient for pollutant concentration; In the formula: k i The combined attenuation coefficient of NH3-N and TP. For time step.

5. The underwater sewage outlet investigation and location method based on data analysis as described in claim 1, characterized in that, In step S4, the environmental sensing device (7) on the hull (1) is used to determine the distance between the hull (1) and the shore and the water depth. The environmental sensing device (7) is a sonar device that emits sonar signals and receives feedback to transmit information to the processor (6). The processor (6) deduces the distance H between the hull (1) and the shore and the bottom of the water based on the sonar information.

6. The underwater sewage outlet investigation and location method based on data analysis as described in claim 5, characterized in that, The pressure acquisition device (3) includes a telescopic rod (3a) composed of multiple rod segments. The lower end of the telescopic rod (3a) is connected to a pressure acquisition plate (3b). The length of each rod segment is L. The number of rods Nmax is determined according to the distance H between the hull (1) and the bottom of the water, and the calculation formula is as follows: In step S5, when collecting pressure data at different depths, the telescopic rod (3a) is extended so that the pressure acquisition plate (3b) is lowered and immersed in the water. The number of rod extension sections is Nmax, where Nmax = {0, 1, 2, ...}. When the number of rods is 0, the pressure acquisition plate (3b) is extended. After extension, it remains still for 1 minute before the pressure sensor is turned on and data is collected. The collection time is 1 minute. After the collection is completed, the next rod is extended, and the above process is repeated until the number of extended rods equals Nmax. After the collection is completed, the pressure acquisition plate (3b) is retracted. When Nmax = 0, only positioning is performed, and pressure detection is abandoned.

7. The underwater sewage outlet investigation and location method based on data analysis as described in claim 6, characterized in that, The pressure acquisition plate (3b) on the pressure acquisition device (3) has 9 pressure sensors (3c) distributed in a 3×3 matrix. In step S7, after the pressure data is Kalman filtered and calibrated for water depth, the pressure submatrix E is output. i After performing Kalman filtering, the average value is retained. Perform water depth calibration, and obtain the actual hydrodynamic pressure value after water depth calibration. The actual values ​​of the obtained hydrodynamic pressure are output to form a pressure submatrix E. i .

8. The underwater sewage outlet investigation and location method based on data analysis as described in claim 7, characterized in that, The pressure submatrix is ​​3 3 matrix The profile pressure matrix Ri is m n matrix, Where m= n = Nmax + 1 and These represent the planar position coordinates of the ship in the waters to be investigated at time t and time t-1, respectively.

Images