A rapid measurement method of water transparency based on drone

Abstract

The present invention provides a method for rapid measurement of water transparency based on an unmanned aerial vehicle, and relates to the technical field of environmental monitoring. The specific implementation method includes: controlling the unmanned aerial vehicle to fly vertically to a predetermined height above the water body; controlling a laser transmitter to emit a laser beam to the water body, and detecting the scattered light intensity on the scattered light path; obtaining the laser intersection imaging information on the scattered light path in real time, and fusing the laser intersection imaging information and the scattered light intensity to obtain the original scattered light intensity; defining a wave correction coefficient, and creating a wave correction coefficient table under different wind speeds; obtaining corresponding wind speed data in real time, and matching the corresponding wave correction coefficient in the wave correction coefficient table; correcting the original scattered light intensity by the wave correction coefficient, and obtaining the corrected scattered light intensity; and calculating the current water transparency according to the corrected scattered light intensity. The present invention has a high degree of automation, reduces human intervention, and greatly improves the accuracy and efficiency of water transparency measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental monitoring, and in particular to a method for quickly measuring water transparency based on an unmanned aerial vehicle. Background Art

[0002] Current methods for quickly obtaining river transparency mainly rely on traditional tools and instruments, such as Secchi disks and transparency meters. Although Secchi disks and transparency meters have certain application value in transparency measurement, they have several technical problems.

[0003] The Secchi disk is a simple measuring tool, usually consisting of a black and white disk and a measuring rod. When using it, slowly lower the Secchi disk into the water until it disappears, and then record the depth as an indicator of transparency. This method is simple to operate, low-cost, and suitable for various water environments, but the measurement method of the Secchi disk relies on manual operation, is highly subjective, and the results are easily affected by human factors and environmental conditions. Different operators may obtain different measurement results in different environments, lacking consistency and repeatability. In addition, the measurement accuracy of the Secchi disk is greatly reduced when used in waves, turbid waters, and deep water environments.

[0004] The transparency meter is a more modern instrument that uses optical principles for measurement. It calculates transparency by emitting a light beam through the water body and detecting the intensity of the light after penetration. The transparency meter has high measurement accuracy and is suitable for refined water quality monitoring. However, its application requires specific equipment and technical support, the equipment cost is high, maintenance is complex, and the professional quality of the operator is required to be high. In addition, in complex field environments, the use of transparency meters is limited by the portability of the equipment and operating conditions, making it difficult to achieve large-scale and rapid transparency monitoring.

[0005] Therefore, the existing technology has problems such as complex operation, strong subjectivity, and high equipment dependence in quickly obtaining river transparency, which makes it difficult to meet the needs of modern environmental monitoring for speed, accuracy, and automation. Summary of the invention

[0006] In view of this, an embodiment of the present application provides a method for rapid measurement of water transparency based on a drone. The embodiment of the present application has a high degree of automation, reduces human intervention, and greatly improves the accuracy and efficiency of water transparency measurement.

[0007] The embodiment of the present application provides the following technical solution: a method for rapid measurement of water transparency based on an unmanned aerial vehicle, comprising:

[0008] Controlling a drone to fly vertically to a predetermined height above a body of water, the drone being equipped with a laser transmitter, a wind speed sensor, and a camera device;

[0009] Controlling the laser transmitter to emit a laser beam to the water body, and using a photoelectric detector to detect the scattered light intensity of the laser beam at different positions and times on the scattered light path;

[0010] The imaging information of the laser intersection corresponding to different positions and times on the scattered light path is acquired in real time by the camera device, and the imaging information of the laser intersection corresponding to different positions and times and the scattered light intensities corresponding to different positions and times are data-fused to obtain the original scattered light intensities corresponding to different positions and times of the laser beam on the scattered light path;

[0011] Simulate the wave characteristics under different wind speed conditions under scattering experimental conditions, analyze the influence of different wave characteristic parameters on the scattered light intensity, define the wave correction coefficient, and create a wave correction coefficient table under different wind speeds;

[0012] According to the wind speed data corresponding to different positions and times on the scattered light path acquired in real time by the wind speed sensor, matching is performed in the wave correction coefficient table according to the wind speed data to obtain the wave correction coefficients corresponding to different positions and times on the scattered light path;

[0013] The original scattered light intensity is corrected by the wave correction coefficient to obtain the corrected scattered light intensity corresponding to different positions and times on the scattered light path; and the current water transparency is calculated based on the corrected scattered light intensity.

[0014] According to an embodiment of the present application, calculating the current water transparency according to the corrected scattered light intensity includes:

[0015] According to the correspondence between the scattered light intensity, the wave correction coefficient and the water transparency, a water transparency database is established, and the corrected scattered light intensity is matched in the water transparency database to obtain reference transparency corresponding to different positions and times on the scattered light path;

[0016] The current water body transparency is obtained by calculation according to the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient.

[0017] According to an embodiment of the present application, a water transparency database is established based on the correspondence between scattered light intensity, wave correction coefficient and water transparency, including:

[0018] Laser imaging data under different water transparency conditions are obtained through experiments, and the phase function is used to simulate the light scattering angle distribution under different water quality conditions. The theoretical scattered light intensity is calculated according to the phase function, and the corresponding scattered light intensity, wave correction coefficient and water transparency are recorded to obtain the water transparency database.

[0019] According to an embodiment of the present application, the imaging information of laser intersections corresponding to different positions and times on the scattered light path is obtained in real time by the camera device, including:

[0020] The two-dimensional laser intersection imaging information corresponding to different positions and times on the scattered light path is obtained in real time by the camera device, and stray light and noise in the two-dimensional laser intersection imaging information are identified and removed by using image filtering and denoising algorithms; key features are extracted from the two-dimensional laser intersection imaging information, and the key features include the scattering angle, position and scattered light intensity distribution of the scattered light.

[0021] According to an embodiment of the present application, according to the following formula, the laser intersection imaging information corresponding to different positions and times and the scattered light intensity corresponding to different positions and times are data fused to obtain the original scattered light intensity corresponding to different positions and times of the laser beam on the scattered light path, including:

[0022]

[0023] in, and are the data weights of the photodetector and camera, is the scattered light intensity obtained from the laser intersection imaging information, is the scattered light intensity obtained by the photodetector, is the intensity of the scattered light after fusion.

[0024] According to an embodiment of the present application, after data fusion of laser intersection imaging information corresponding to different positions and times and scattered light intensities corresponding to different positions and times, the method further includes:

[0025] The theoretical incident light intensity of the laser beam is calculated, and the ratio of the fused scattered light intensity to the theoretical incident light intensity is calculated, the fused scattered light intensity is normalized, and the obtained normalized scattered light intensity is used as the original scattered light intensity.

[0026] According to an embodiment of the present application, wave characteristics under different wind speed conditions are simulated under scattering experimental conditions, the influence of different wave characteristic parameters on the scattered light intensity is analyzed, and a wave correction coefficient is defined, wherein the wave correction coefficient is defined as the following formula:

[0027]

[0028] in, is the wave correction factor, is the correction factor for the incident angle variation, is the correction factor for optical path length variation, is the surface reflection correction factor.

[0029] According to one embodiment of the present application, the wave characteristic parameters include amplitude, wavelength and wave surface inclination angle.

[0030] According to an embodiment of the present application, the formula for correcting the original scattered light intensity by the wave correction coefficient is as follows:

[0031] =

[0032] in, is the corrected scattered light intensity, is the original scattered light intensity, is the wave correction factor.

[0033] According to an embodiment of the present application, the current water transparency is obtained by calculating the following formula based on the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient:

[0034]

[0035] Among them, T c is the current water transparency, I s is the current scattered light intensity, is the wave correction factor, T d（1.2...n） is the reference transparency, and n is the number of reference transparency values ​​matched in the water transparency database.

[0036] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0037] 1. The embodiment of the present invention reduces environmental interference and ensures the accuracy of laser scattering data by adjusting the laser and intelligent wave correction algorithm in real time, thereby greatly improving the accuracy of water transparency measurement.

[0038] 2. The embodiment of the present invention adopts an unmanned aerial vehicle platform and multi-sensor fusion technology, so that the system can adapt to different types of water bodies and complex environments, with a high degree of automation, reducing human intervention, and improving measurement efficiency and convenience of data acquisition.

[0039] 3. The embodiment of the present invention uses the technology of matching laser reflection data with transparency database to realize the real-time calculation and output of water transparency, providing timely and accurate decision support for environmental monitoring and water resources management. In addition, multi-sensor data fusion and intelligent wave correction algorithm ensure the reliability and consistency of measurement data, providing a high-quality data foundation for subsequent water quality analysis and pollution assessment.

[0040] 4. The embodiments of the present invention are not only suitable for monitoring large-scale lakes, rivers and other water bodies, but can also be applied to water quality monitoring in complex environments such as urban rivers and reservoirs, which expands the application scope of the technology and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a schematic flow chart of a method for rapid measurement of water transparency based on a drone according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0044] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0045] like Figure 1 As shown, an embodiment of the present invention provides a method for quickly measuring water transparency based on a drone, comprising:

[0046] S101. Controlling the UAV to fly vertically to a predetermined height above the water body, wherein the UAV is equipped with a laser transmitter, a wind speed sensor and a camera device;

[0047] S102. Control the laser emitter to emit a laser beam to the water body, and use a photoelectric detector to detect the scattered light intensity of the laser beam at different positions and times on the scattered light path;

[0048] S103. Obtaining the laser intersection imaging information corresponding to different positions and times on the scattered light path in real time by means of the camera device, fusing the laser intersection imaging information corresponding to different positions and times with the scattered light intensities corresponding to different positions and times, and obtaining the original scattered light intensities corresponding to different positions and times of the laser beam on the scattered light path;

[0049] S104. Simulate the wave characteristics under different wind speed conditions under the scattering experiment conditions, analyze the influence of different wave characteristic parameters on the scattered light intensity, define the wave correction coefficient, and create a wave correction coefficient table under different wind speeds;

[0050] S105. According to the wind speed data corresponding to different positions and times on the scattered light path acquired in real time by the wind speed sensor, matching is performed in the wave correction coefficient table according to the wind speed data to obtain the wave correction coefficients corresponding to different positions and times on the scattered light path;

[0051] S106. Correct the original scattered light intensity by using the wave correction coefficient to obtain the corrected scattered light intensity corresponding to different positions and times on the scattered light path; calculate the current water transparency according to the corrected scattered light intensity.

[0052] According to a specific implementation method of an embodiment of the present invention, in step S106, the current water body transparency is calculated according to the corrected scattered light intensity, including: establishing a water body transparency database according to the correspondence between the scattered light intensity, the wave correction coefficient and the water body transparency, matching the corrected scattered light intensity in the water body transparency database to obtain the reference transparency corresponding to different positions and times on the scattered light path; calculating the current water body transparency according to the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient.

[0053] Among them, a water transparency database is established according to the correspondence between scattered light intensity, wave correction coefficient and water transparency, including: obtaining laser imaging data under different water transparency conditions through experiments, simulating the light scattering angle distribution under different water quality conditions by using a phase function, and calculating the theoretical scattered light intensity according to the phase function. Record the corresponding scattered light intensity, wave correction coefficient and water transparency to obtain the water transparency database.

[0054] According to a specific implementation method of an embodiment of the present invention, in step S103, the laser intersection imaging information corresponding to different positions and times on the scattered light path is obtained in real time by the camera device, including: according to the camera device, two-dimensional laser intersection imaging information corresponding to different positions and times on the scattered light path is obtained in real time, and image filtering and denoising algorithms are used to identify and remove stray light and noise in the two-dimensional laser intersection imaging information; key features are extracted from the two-dimensional laser intersection imaging information, and the key features include the scattering angle, position and scattered light intensity distribution of the scattered light.

[0055] Furthermore, according to the following formula, the laser intersection imaging information corresponding to different positions and times and the scattered light intensity corresponding to different positions and times are data fused to obtain the original scattered light intensity corresponding to different positions and times of the laser beam on the scattered light path, including:

[0056]

[0057] in, and are the data weights of the photodetector and camera, is the scattered light intensity obtained from the laser intersection imaging information, is the scattered light intensity obtained by the photodetector, is the intensity of the scattered light after fusion.

[0058] According to a specific implementation method of an embodiment of the present invention, in step S103, after the laser intersection imaging information corresponding to different positions and times and the scattered light intensities corresponding to different positions and times are fused, it also includes: calculating the theoretical incident light intensity of the laser beam, and calculating the ratio of the fused scattered light intensity to the theoretical incident light intensity, normalizing the fused scattered light intensity, and using the obtained normalized scattered light intensity as the original scattered light intensity.

[0059] According to a specific implementation of an embodiment of the present invention, in step S104, wave characteristics under different wind speed conditions are simulated under scattering experimental conditions, the influence of different wave characteristic parameters on the scattered light intensity is analyzed, and a wave correction coefficient is defined, wherein the wave correction coefficient is defined as follows:

[0060]

[0061] in, is the wave correction factor, is the correction factor for the incident angle variation, is the correction factor for optical path length variation, is the surface reflection correction coefficient. Wherein, the wave characteristic parameters include wave amplitude, wavelength and wave surface inclination angle.

[0062] The embodiment of the present invention, when implemented, includes the following steps:

[0063] Step 1: The drone is equipped with a laser transmitter, a camera and a wind speed sensor and flies vertically above the water surface; the drone is controlled to fly vertically to a predetermined height so that it is above the water body to facilitate subsequent laser measurement and optical sensor work.

[0064] Control the direction of the laser transmitter to shoot a laser beam towards the water.

[0065] Step 2: Detect the intensity of the scattered beam at each point

[0066] The photodetector records the scattering of the laser light path and captures the laser scattering signal.

[0067] (1) Henyey-Greenstein phase function

[0068] This function describes the angular distribution of light during single scattering in a medium and is suitable for simulating the scattering behavior of light in water.

[0069]

[0070] in, : The phase function value under the scattering angle θ and asymmetry factor g; θ: scattering angle, that is, the angle between the incident light and the scattered light; g: asymmetry factor, ranging from −1≤g≤1, reflecting the directionality of scattering; g=0: isotropic scattering, g>0: forward scattering is dominant, g<0: backward scattering is dominant.

[0071] (2) Gaussian beam intensity distribution formula

[0072] This formula describes the intensity distribution of a laser beam in a cross section, assuming that the laser is an ideal Gaussian beam.

[0073]

[0074] Where I(r) is the light intensity at a radial distance r from the central axis of the beam, P is the output power of the laser, and ω0 is the beam waist radius, which refers to the point at which the light intensity drops to 1 / e of the maximum value. 2 Radial distance at, r: Radial distance, the distance between the measuring point and the center of the beam.

[0075] The role and purpose of detecting the scattered light intensity at each point: By measuring the scattered light intensity I(r) at different positions, the scattering characteristics of the water body, including the scattering coefficient and the asymmetry factor g, can be obtained. Multi-point scattered light intensity data can more accurately reflect the actual situation of the water body and help improve the accuracy of database matching.

[0076] The following examples describe this process in detail:

[0077] (1) UAV positioning and laser emission

[0078] Control the drone to hover at a specified height above the target water area to ensure that the laser is vertically directed toward the water surface. Set an appropriate laser power P to ensure sufficient detection signal strength. Select an appropriate beam waist radius ω0 according to the measurement requirements.

[0079] (2) Detecting scattered light intensity

[0080] Install multiple photoelectric detectors under or on the side of the drone to capture scattered light at different distances r. Record the position (r) of each detector and the corresponding scattered light intensity I in real time. s (r).

[0081] (3) Data processing

[0082] ① Calculate the incident light intensity I0

[0083] Using the Gaussian beam intensity distribution formula, calculate the theoretical incident light intensity I0(r) at each position without scattering:

[0084]

[0085] ②Normalized scattered light intensity

[0086] The measured scattered light intensity I s (r) is compared with the incident light intensity I0(r) to obtain the normalized scattered light intensity I norm (r).

[0087]

[0088] ③ Apply the Henyey-Greenstein phase function

[0089] Using the normalized scattered intensity I norm (r), fit the Henyey-Greenstein phase function and solve for the asymmetry factor g. Use the least squares method or other optimization algorithms to find the g value that best fits the measured data.

[0090] Based on the results obtained in the above steps, wave impact correction is performed, transparency is calculated, and the corrected light intensity data is compared with the transparency database to obtain the current transparency of the water body.

[0091] Step 3: Use the high resolution of the camera to synchronize with the photodetector to obtain the global information of laser scattering in real time. According to the laser intersection imaging recorded by the camera, use the algorithm to remove stray light and noise to obtain the two-dimensional scattering data of the camera. Fuse the scattering data of the camera and the photodetector to obtain the original scattered light intensity. Carry out indoor tests, record wind speed, define wave correction coefficients, and correct the original scattered light intensity for wave effects.

[0092] (1) Imaging data processing

[0093] Analyze the two-dimensional laser intersection imaging recorded by the camera, and use digital image processing technology to extract key features such as the scattering angle, position, and intensity distribution of the scattered light. Use image filtering and denoising algorithms, such as Gaussian filtering, to identify and remove stray light and noise. Map the position of the photodetector to the coordinate system of the camera and perform coordinate conversion. Use methods such as Kalman filtering or weight formulas to fuse the data of the camera and photodetector to obtain the original scattered light intensity. .

[0094] (2) Scattered light intensity correction

[0095] The wave correction coefficient is calculated based on the wind speed sensor equipped by the drone to correct the scattered light intensity.

[0096] The following examples provide a detailed description of the process:

[0097] (1) Fusion of scattered light intensity (such as weighting method)

[0098]

[0099] and They are the data weights of the photodetector and the camera, respectively, and can be determined based on parameters such as the sensor's signal-to-noise ratio and measurement accuracy. is the scattered light intensity obtained by high-resolution image processing. is the scattered light intensity obtained by the photodetector.

[0100] (2) Calculation of wave correction coefficient

[0101] Under the conditions of the scattering experiment, the wave characteristics (amplitude, wavelength, wave surface frequency) under different wind speed conditions are simulated and measured, the influence of different wave characteristic parameters on the scattered light intensity is analyzed, the wave correction coefficient is defined and calculated, and the wave correction coefficient table under different wind speeds is created.

[0102] Total significant wave height (i.e. significant wave height) With wind speed The relationship is:

[0103]

[0104] The wavelength λ is related to the wave frequency f by the dispersion relation:

[0105]

[0106] Simplify irregular waves into regular waves, for:

[0107]

[0108] Wave surface tilt angle :

[0109]

[0110] The water surface fluctuation caused by waves will cause the correction factor of the incident angle to change , Optical path length change correction factor , surface reflection correction factor Therefore, in order to quantify the effect of waves on the scattered light intensity, the wave correction factor is defined as :

[0111]

[0112] Angle of incidence: =

[0113] The refraction angle, the refraction angle of laser in water, satisfies Snell's law:

[0114]

[0115] Correction factor for incident angle variation :

[0116]

[0117] Optical path length variation correction factor :

[0118]

[0119] According to the Fresnel formula, the surface reflectivity R is:

[0120]

[0121] Surface reflection correction factor :

[0122]

[0123] (3) Correction of scattered light intensity

[0124] According to the acquired wind speed data on the scattered light path, a match is made in the wave correction coefficient table to obtain the corresponding wave correction coefficient.

[0125] The original scattered light intensity affected by the waves is , the corrected scattered light intensity is:

[0126] =

[0127] in, is the corrected scattered light intensity, is the original scattered light intensity, is the wave correction factor.

[0128] Use the corrected scattered light intensity Carry out subsequent water transparency calculations.

[0129] Step 4: Automatically calculate water transparency based on the water transparency database corresponding to different laser conditions in the database. Specifically, compare the corrected scattered light intensity with the different laser conditions and water transparency data in the database. The database contains water transparency values ​​corresponding to different laser intersection imaging conditions, and establishes a comprehensive reference transparency model. Based on the database matching results, automatically calculate the transparency of the current water body. Store and output the calculated water transparency data for further analysis and decision support.

[0130] According to the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient, the current water transparency is calculated by the following formula:

[0131]

[0132] Among them, T c is the current water transparency, I s is the current scattered light intensity, is the wave correction factor, which is used to correct the laser scattering changes caused by surface waves and usually needs to be calibrated according to specific circumstances; T d（1.2...n） is the reference transparency value matched from the water transparency database, and n is the number of reference transparency values ​​matched in the water transparency database.

[0133] The following examples provide a detailed description of the process:

[0134] (1) Establishing a water transparency database

[0135] In water bodies with known transparency, laser imaging data under different transparency conditions are obtained through experiments. The phase function is used to simulate the light scattering angle distribution under different water quality conditions. The theoretical scattered light intensity calculated by the phase function is compared with the actual measured data to verify the accuracy of the model. The corresponding scattering intensity I is recorded. s , wave correction factor and water transparency T c The above data are stored in a database to form a correlation between scattering intensity, wave correction coefficient and transparency.

[0136] (2) Acquisition of actual measurement data

[0137] The camera on the drone captures the scattered image of the laser in the water, extracts the current scattering intensity value, uses the wind speed sensor to measure the current wind speed, and calculates the correction coefficient according to the above method. , correct the normalized scattered light intensity and obtain .

[0138] (3) Database matching

[0139] The actual measured scattered light intensity distribution is matched with the scattered light intensity distribution generated in the database based on the phase function to find the closest water transparency value. At the same time, the database is searched for the scattered light intensity distribution that matches the current corrected value. Similar records, extract the transparency value T corresponding to all records that meet the conditions d1 ,T d2 ,…,T dn . Set a tolerance range δ to meet the following conditions:

[0140]

[0141] in, is the scattering intensity value in the database.

[0142] (4) Calculate the average transparency T avg :Average the transparency values ​​matched from the database to get a more accurate reference value. By averaging the matched transparency values, the error that may be caused by a single data can be reduced.

[0143]

[0144] The embodiment of the present invention uses a drone equipped with a laser transmitter to determine the transparency of the water body through the scattered signal of the laser, which has the advantages of being fast, contactless, intelligent and automated. A light sensor is used to detect the scattered light intensity of each point on the light path to determine the transparency. The light sensor detection can detect the scattered light intensity of each point on the light path, and automatically calculate the transparency of the water body according to the matching of the laser reflection data with the transparency database and the comparison of the laser reflection imaging, thereby improving the flexibility and accuracy of the measurement. The wave coefficient is used to reduce the measurement error. The embodiment of the present invention introduces an intelligent wave influence correction algorithm. Based on the light intensity, wave characteristics, and wind speed data of the reflection point recorded by the light sensor and the high-resolution camera under experimental conditions, a wave model is established to determine the wave coefficient. The parameters are applied to the actual measurement, and the wave correction coefficient is used to correct the scattered light intensity, ultimately improving the accuracy of the water transparency measurement.

[0145] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for rapid measurement of water transparency based on drones, characterized in that: include: Controlling a drone to fly vertically to a predetermined height above a body of water, the drone being equipped with a laser transmitter, a wind speed sensor, and a camera device; Controlling the laser transmitter to emit a laser beam to the water body, and using a photoelectric detector to detect the scattered light intensity of the laser beam at different positions and times on the scattered light path; The imaging information of the laser intersection corresponding to different positions and times on the scattered light path is acquired in real time by the camera device, and the imaging information of the laser intersection corresponding to different positions and times and the scattered light intensities corresponding to different positions and times are data-fused to obtain the original scattered light intensities corresponding to different positions and times of the laser beam on the scattered light path; Simulate the wave characteristics under different wind speed conditions under scattering experimental conditions, analyze the influence of different wave characteristic parameters on the scattered light intensity, define the wave correction coefficient, and create a wave correction coefficient table under different wind speeds; According to the wind speed data corresponding to different positions and times on the scattered light path acquired in real time by the wind speed sensor, matching is performed in the wave correction coefficient table according to the wind speed data to obtain the wave correction coefficients corresponding to different positions and times on the scattered light path; The original scattered light intensity is corrected by the wave correction coefficient to obtain the corrected scattered light intensity corresponding to different positions and times on the scattered light path; The current water transparency is calculated according to the corrected scattered light intensity.

2. The method for rapid measurement of water transparency based on drone according to claim 1 is characterized in that: Calculating the current water transparency according to the corrected scattered light intensity, including: According to the correspondence between the scattered light intensity, the wave correction coefficient and the water transparency, a water transparency database is established, and the corrected scattered light intensity is matched in the water transparency database to obtain reference transparency corresponding to different positions and times on the scattered light path; The current water body transparency is obtained by calculation according to the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient.

3. The method for rapid measurement of water transparency based on drone according to claim 2 is characterized in that: According to the corresponding relationship between scattered light intensity, wave correction coefficient and water transparency, a water transparency database is established, including: Laser imaging data under different water transparency conditions are obtained through experiments, and the phase function is used to simulate the light scattering angle distribution under different water quality conditions. The theoretical scattered light intensity is calculated according to the phase function, and the corresponding scattered light intensity, wave correction coefficient and water transparency are recorded to obtain the water transparency database.

4. The method for rapid measurement of water transparency based on drone according to claim 1 is characterized in that: The imaging information of laser intersections corresponding to different positions and times on the scattered light path is obtained in real time by the camera device, including: The two-dimensional laser intersection imaging information corresponding to different positions and times on the scattered light path is obtained in real time by the camera device, and stray light and noise in the two-dimensional laser intersection imaging information are identified and removed by using image filtering and denoising algorithms; key features are extracted from the two-dimensional laser intersection imaging information, and the key features include the scattering angle, position and scattered light intensity distribution of the scattered light.

5. The method for rapid measurement of water transparency based on drone according to claim 1 is characterized in that: According to the following formula, the laser intersection imaging information corresponding to different positions and times and the scattered light intensity corresponding to different positions and times are fused to obtain the original scattered light intensity corresponding to different positions and times of the laser beam on the scattered light path, including: in, and are the data weights of the photodetector and camera, is the scattered light intensity obtained from the laser intersection imaging information, is the scattered light intensity obtained by the photodetector, is the intensity of the scattered light after fusion.

6. The method for rapid measurement of water transparency based on drone according to claim 5 is characterized in that: After the laser intersection imaging information corresponding to different positions and times and the scattered light intensity corresponding to different positions and times are fused, it also includes: The theoretical incident light intensity of the laser beam is calculated, and the ratio of the fused scattered light intensity to the theoretical incident light intensity is calculated, the fused scattered light intensity is normalized, and the obtained normalized scattered light intensity is used as the original scattered light intensity.

7. The method for rapid measurement of water transparency based on drone according to claim 1 is characterized in that: Under the scattering experiment conditions, the wave characteristics under different wind speed conditions are simulated, the influence of different wave characteristic parameters on the scattered light intensity is analyzed, and the wave correction coefficient is defined, wherein the wave correction coefficient is defined as follows: in, is the wave correction factor, is the correction factor for the incident angle variation, is the correction factor for optical path length variation, is the surface reflection correction factor.

8. The method for rapid measurement of water transparency based on drone according to claim 7 is characterized in that: The wave characteristic parameters include wave amplitude, wavelength and wave surface inclination angle.

9. The method for rapid measurement of water transparency based on drone according to claim 1 is characterized in that: The formula for correcting the original scattered light intensity by the wave correction coefficient is as follows: = in, is the corrected scattered light intensity, is the original scattered light intensity, is the wave correction factor.

10. The method for rapid measurement of water transparency based on drone according to claim 2 is characterized in that: According to the reference transparency, the current scattered light intensity and the corresponding wave correction coefficient, the current water transparency is calculated by the following formula: Among them, T c is the current water transparency, I s is the current scattered light intensity, is the wave correction factor, T d（1.2...n） is the reference transparency, and n is the number of reference transparency values ​​matched in the water transparency database.

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