A wind-blown snow particle adaptive imaging measurement system and method based on double-view field fusion

Abstract

The present application relates to a kind of wind snow particle adaptive imaging measurement system and method based on double view field fusion, system includes: optical illumination unit, double view field imaging unit, field of view switching unit, data acquisition control unit, data processing unit;Optical illumination unit, for illuminating sampling space;Double view field imaging unit, for wind snow particle double view field imaging;Field of view switching unit, for controlling double view field imaging unit field of view switching and adjustment;Data acquisition control unit, for controlling optical illumination unit and double view field imaging unit, wind snow particle image data acquisition;Data processing unit, for wind snow particle image data processing and display.The present application is based on the development of large field of view and small field of view array camera, can provide important data support for atmospheric science research, snow field observation, weather modification etc..

Description

TECHNICAL FIELD

[0001] The present application relates to the meteorological monitoring technical field, in particular to a wind-blowing snow particle adaptive imaging measurement system and method based on double-view field fusion, which is suitable for multi-parameter dynamic detection of wind-blowing snow particles in complex wind field environment. BACKGROUND

[0002] Wind-blowing snow phenomenon is widely distributed in cold regions, which has a significant impact on transportation, power infrastructure, agricultural production and other fields. Accurate determination of the speed, particle size and morphology of wind-blowing snow particles and other parameters is crucial for understanding the formation mechanism of wind-blowing snow, predicting its hazards and developing effective protection strategies. Snow particle counter (SPC) can directly measure the micro characteristics of wind-blowing snow, but it can only obtain the size and number information of wind-blowing snow particles in a very small sampling space. In order to obtain the particle size and speed distribution information in a larger space range, some scholars have used PIV (particle image velocimetry) and PTV (particle tracking velocimetry) techniques for wind-blowing snow measurement in different range fields. However, the above measurement methods have limitations. Single range field is difficult to balance the wide range measurement of particle velocity field and the high precision measurement of particle diameter and morphology. Although large field measurement can obtain the particle velocity field, it lacks in the measurement accuracy of particle diameter and morphology. Small field measurement can accurately measure the particle diameter and morphology, but it cannot effectively cover a larger range for particle velocity field measurement. Moreover, fixed focal length system is difficult to adapt to the best focusing requirements of particles of different diameters, and frequent mechanical field switching also leads to reduced time resolution and limited dynamic tracking capability. Therefore, it is of great practical significance to develop a wind-blowing snow particle measurement system and method that integrates the advantages of large and small fields for better observation of wind-blowing snow phenomenon. SUMMARY

[0003] The purpose of the present application is to provide a wind-blowing snow particle adaptive imaging measurement system and method based on double-view field fusion to solve the problems existing in the prior art. The method combines large field and small field imaging and uses field switching technology to realize large range flow field measurement and small range particle tracking in precipitation scene.

[0004] To achieve the above purpose, the present application discloses a wind-blowing snow particle adaptive imaging measurement system based on double-view field fusion, which comprises an optical illumination unit, a double-view field imaging unit, a field switching unit, a data acquisition and control unit and a data processing unit.

[0005] The optical illumination unit is used to illuminate the sampling space.

[0006] The dual-view field imaging unit is configured to perform dual-view field imaging on the wind-blown snow particles.

[0007] The field-of-view switching unit is configured to control the dual-view field imaging unit to switch and adjust the field of view.

[0008] The data acquisition control unit is configured to control the optical illumination unit and the dual-view field imaging unit to acquire the wind-blown snow particle image data.

[0009] The data processing unit is configured to process and display the wind-blown snow particle image data.

[0010] Optionally, the optical illumination unit comprises a first illumination module and a second illumination module.

[0011] The first illumination module is configured to provide a high-repetition-frequency LED light source to extract the particle velocity field.

[0012] The second illumination module is configured to provide a constant-brightness LED light source to perform real-time continuous tracking measurement on the wind-blown snow particles.

[0013] The first illumination module and the second illumination module are located on the same side of the target imaging field of view.

[0014] Optionally, the dual-view field imaging unit comprises a first view field imaging module and a second view field imaging module.

[0015] The first view field imaging module is configured to acquire continuous image data of wind-blown snow particles in a first target range.

[0016] The second view field imaging module is configured to acquire high-definition continuous image data of wind-blown snow particles in a second target range; wherein the first target range is larger than the second target range.

[0017] The first view field imaging module is placed perpendicular to the sampling plane, the second view field imaging module is cross-mounted with the first view field imaging module at a preset angle, and the optical axes of the first view field imaging module and the second view field imaging module coincide, the particles observed by the two modules are in the same spatial coordinate system, and the sampling plane formed by the first view field imaging module has a fixed field of view while the field of view of the second view field imaging module is adjustable.

[0018] Optionally, the field-of-view switching unit comprises a switchable mirror module and a translation device.

[0019] The switchable mirror module is configured to integrate the optical paths of the first view field imaging module and the second view field imaging module into the same main optical axis.

[0020] The translation device is configured to carry the second view field imaging module and adjust the working distance of the second view field imaging module.

[0021] The switchable mirror module is mounted on the optical axis of the first field-of-view imaging module and the second field-of-view imaging module, and is driven by a motor to control the angle and realize dynamic switching of the light reflection path.

[0022] Optionally, the data acquisition control unit comprises a triggering module, an exposure driving module, an image acquisition module and an image transmission module.

[0023] The triggering module is configured to trigger the first field-of-view imaging module to start collecting image data when the second field-of-view imaging module detects that a particle passes.

[0024] The exposure driving module is configured to synchronously start the first illumination module when the first field-of-view imaging module starts collecting image data.

[0025] The image acquisition module is configured to time-pair and encode the image data collected by the first field-of-view imaging module and the image data collected by the second field-of-view imaging module, and then transmit the encoded image data to the data processing unit in real time through the image transmission module.

[0026] Optionally, the data processing unit comprises a preprocessing module and a matching module.

[0027] The preprocessing module is configured to preprocess the wind-blown snow particle image data, and obtain microphysical parameters of wind-blown snow particles in different fields of view based on the preprocessed image, wherein the microphysical parameters comprise diameter, outline and speed.

[0028] The matching module is configured to realize time sequence matching of wind-blown snow particles by using the microphysical parameters, and obtain the motion speed of wind-blown snow particles and the wide-range particle speed field vector distribution according to the motion trajectory of wind-blown snow particles between continuous frames.

[0029] Optionally, the preprocessing of the wind-blown snow particle image data by the preprocessing module comprises:

[0030] The wind-blown snow particle image data is subjected to background separation processing and binarization processing to identify and extract wind-blown snow particles, and the trajectory tracking and speed calculation of wind-blown snow particles are realized by using a particle matching algorithm.

[0031] Optionally, the data processing unit further comprises a display module.

[0032] The display module is configured to display the microphysical parameters and the motion trajectory of wind-blown snow particles by using data visualization technology.

[0033] To achieve the above object, the application further discloses a wind-blowing snow particle adaptive imaging measurement method based on double-view field fusion, comprising the following steps of:

[0034] Initializing the measurement system, starting the optical illumination unit, the double-view field imaging unit, the view field switching unit, and the data acquisition control unit;

[0035] The trigger module drives the second view field imaging module to scan the sampling space, and detects whether the wind-blowing snow particle exists through the interframe difference processing of the high-frame-rate continuous image; when there is no wind-blowing snow particle in the sampling space, the first view field imaging module and the exposure are not started;

[0036] When the second view field imaging module detects that the wind-blowing snow particle appears in the sampling space, the trigger module transmits a synchronous trigger pulse to the exposure driving module, starts the first view field imaging module and the first illumination module, realizes the synchronous exposure of the wind-blowing snow particle in the double view field, and obtains the distribution image of the wind-blowing snow particle in the large view field;

[0037] After the second view field imaging module detects the particle, the system sends a trigger signal, starts the large view field camera to start image acquisition, the first illumination module flashes to illuminate the particles in the large view field range at a set frequency, and the large view field camera shoots multiple particle images;

[0038] When the first view field imaging module works, the second view field imaging module continues to measure the particle, the translation device automatically adjusts the working distance of the second view field imaging module according to the distance information of the particle and the camera, and optimizes the focusing effect;

[0039] The data processing unit analyzes the large view field particle image, obtains the wind-blowing snow particle velocity field distribution, analyzes the small view field particle image, obtains the diameter, contour and speed parameters of the particle, performs fusion processing according to the position correspondence of the particle in different view fields, and stores and analyzes the fused data;

[0040] With the continuous movement of the wind-blowing snow particle, when the particle leaves the current view field range, the next possible particle position is predicted according to the movement direction and speed of the particle, the angle of the switchable mirror is adjusted through the control system, the view field is switched to the predicted position, and continuous and adaptive measurement is realized.

[0041] Optionally, the step of initializing the measurement system, starting the optical illumination unit, the double-view field imaging unit, the view field switching unit, and the data acquisition control unit comprises the following steps of:

[0042] The measurement range of the first view field imaging module, the resolution of the second view field imaging module, the moving step of the translation device, and the illumination parameter of the first illumination module are determined, the optical axes of the second view field imaging module and the first view field imaging module are ensured to be coincident, and the switchable mirror is set to the initial state so that the light enters the second view field imaging module.

[0043] The beneficial effects of the present application are:

[0044] The wind-blown snow particle adaptive imaging measurement system and method based on double field of view fusion provided by the present application realize high-precision wind-blown snow particle parameter measurement through the large and small field of view fusion technology: the large field of view camera is responsible for global particle velocity field measurement, and the small field of view camera focuses on the fine detection of particle size and shape, and the two work together to improve the parameter measurement accuracy; an adaptive field of view switching mechanism is adopted, the large field of view camera is driven to work based on the real-time detection result of the small field of view, and the field of view is dynamically adjusted through the switchable mirror, which significantly enhances the measurement flexibility and efficiency, and the coaxial design of the optical axis makes the large and small fields of view share the coordinate system, which can avoid the problem of trajectory break caused by field of view switching; in addition, the system integrates a high-precision electric translation stage to optimize the working distance of the small field of view camera for dynamic focusing compensation, ensuring that the particles are always in a clear imaging state, and further improving the accuracy of micro parameter measurement. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0046] Figure 1 The composition block diagram of the wind-blown snow particle adaptive imaging measurement system based on double field of view fusion according to an embodiment of the present application is shown in the figure.

[0047] Figure 2 The imaging schematic diagram according to an embodiment of the present application is shown in the figure.

[0048] Figure 3 The workflow diagram of the wind-blown snow particle adaptive imaging measurement method based on double field of view fusion according to an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only constitute some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0050] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0051] As Figure 1As shown, this embodiment proposes an adaptive imaging measurement system for windblown snow particles based on dual-field-of-view fusion, including: an optical illumination unit, a dual-field-of-view imaging unit, a field-of-view switching unit, a data acquisition and control unit, and a data processing unit;

[0052] The system includes an optical illumination unit for illuminating the sampling space; a dual-field imaging unit for imaging windblown snow particles in a dual-field manner; a field-of-view switching unit for controlling the dual-field imaging unit to switch and adjust the field of view; a data acquisition and control unit for controlling the optical illumination unit and the dual-field imaging unit to acquire windblown snow particle image data; and a data processing unit for processing and displaying the windblown snow particle image data.

[0053] Furthermore, the optical illumination unit includes: a first illumination module and a second illumination module;

[0054] Specifically, in this embodiment, the first illumination module uses a high repetition rate LED light source, and the second illumination module uses a constant-on LED light source. The high repetition rate LED light source and the constant-on LED light source are located on the same side of the target imaging field of view and are used to illuminate the sampling plane.

[0055] Among them, the high repetition rate LED light source provides illumination for large field-of-view measurement, enabling the extraction of particle velocity fields; the constant-light LED light source provides illumination for small field-of-view measurement, enabling real-time continuous tracking and measurement of windblown snow particles.

[0056] Furthermore, the dual-field-of-view imaging unit includes: a first field-of-view imaging module and a second field-of-view imaging module;

[0057] Specifically, in this embodiment, the first field-of-view imaging module uses a large field-of-view imaging camera, and the second field-of-view imaging module uses a small field-of-view imaging camera.

[0058] Among them, the large field-of-view imaging camera is used to acquire continuous images of a large area of ​​windblown snow particles, while the small field-of-view imaging camera is used to acquire high-definition continuous images of a small area of ​​windblown snow particles.

[0059] In the dual-field-of-view imaging unit, the large-field-of-view imaging camera is placed perpendicular to the sampling plane, while the small-field-of-view imaging camera is erected at a preset angle, with their relative positions depending on the optical path angle of the switchable mirror. Furthermore, the optical axes of the large-field-of-view and small-field-of-view imaging cameras are strictly aligned to ensure that the particles observed by both cameras are in the same spatial coordinate system, avoiding spatial registration errors after field-of-view switching. A high-repetition-rate LED light source and a constant-on LED light source are located on the same side of the sampling plane to illuminate the sampling space. The dual-field-of-view imaging unit images windblown snow particles by receiving scattered and reflected light. The high-repetition-rate LED light source has an adjustable flashing frequency, which, in conjunction with the camera frame rate, illuminates the particles, preventing motion trailing. The imaging optical path is as follows: Figure 2 As shown.

[0060] The large field of view imaging camera adopts a large aperture lens, and has an imaging range of 1 m x 1 m and a maximum frame rate of 40 frames / s, and is used for global particle velocity field measurement; the small field of view imaging camera adopts a small aperture lens, and has an imaging range of 0.1 m x 0.1 m and a maximum frame rate of 1000 frames / s, and is used for fine measurement of particle size and shape. The optical axes of the large field of view imaging camera and the small field of view imaging camera are strictly coincident, and constitute a sampling plane with a large field of view being constant and a small field of view being adjustable. The included angle between the main axes of the large / small field of view imaging cameras is adjustable in a range of 20° to 120°, and the angle depends on the light path angle of the switchable mirror.

[0061] The exposure time of the large field of view imaging camera depends on the lighting time length of the high-frequency LED light source, and can adopt a single frame single exposure and a single frame multi-exposure mode, and the single exposure time length is adjustable in a range of 1 μs to 1 ms, and the exposure interval time is adjustable in a range of 1 μs to 1 ms.

[0062] When the small field of view imaging camera detects wind-blowing snow particles in the field of view, the large field of view imaging camera is started to work for high-precision synchronous exposure, and a high-precision pulse signal is output by a high-precision clock manager, and the delay of synchronous triggering is not more than 10 ns.

[0063] Further, the field of view switching unit comprises a switchable mirror module and a translation device.

[0064] Specifically, in the embodiment, the translation device adopts a high-precision electric translation stage; the switchable mirror module adopts a coated beam splitter or a switchable mirror group, and is used for integrating the light paths of the first field of view imaging module and the second field of view imaging module into the same main optical axis; and the high-precision electric translation stage is used for fine adjustment of the field of view of the small field of view camera.

[0065] The switchable mirror module is installed on the optical axes of the large / small field of view lenses, and is driven and controlled by a motor to control the angle, so as to realize dynamic switching of the light reflection path and ensure rapid adjustment of the field of view. The high-precision electric translation stage carries the small field of view camera, has a moving precision of 0.5 mm and a maximum stroke of 100 mm, and is used for real-time adjustment of the working distance of the camera to optimize focusing.

[0066] Further, the data acquisition control unit comprises a trigger module, an exposure driving module, an image acquisition module and an image transmission module.

[0067] The trigger module is used for triggering the first field of view imaging module to start collecting image data when the second field of view imaging module detects that there is a particle passing through.

[0068] The exposure driving module is used for synchronously starting the first illumination module when the first field of view imaging module starts collecting image data.

[0069] The image acquisition module is configured to time-pair and encode the image data acquired by the first field-of-view imaging module and the image data acquired by the second field-of-view imaging module, and then transmit the encoded image data to the data processing unit in real time through the image transmission module.

[0070] Further, the data processing unit comprises a preprocessing module and a matching module.

[0071] The preprocessing module is configured to preprocess the wind-blown snow particle image data, and acquire microphysical parameters of the wind-blown snow particles in different fields of view based on the preprocessed image, wherein the microphysical parameters include diameter, outline and speed.

[0072] The matching module is configured to realize time-series matching of the wind-blown snow particles by using the microphysical parameters, and acquire the motion speed of the wind-blown snow particles and the wide-range particle speed field vector distribution according to the motion trajectory of the wind-blown snow particles between continuous frames.

[0073] Further, the preprocessing of the wind-blown snow particle image data by the preprocessing module comprises:

[0074] The background separation processing binarizes the wind-blown snow particle image, identifies and extracts the wind-blown snow particles, and realizes trajectory tracking and speed calculation of the wind-blown snow particles by using a particle matching algorithm.

[0075] Further, the data processing unit further comprises a display module, and the display module is configured to display the microphysical parameters and the motion trajectory of the wind-blown snow particles by using a data visualization technology.

[0076] The embodiment also discloses a wind-blown snow particle adaptive imaging measurement method based on double-field-of-view fusion, as shown in Figure 3 The method comprises the following steps:

[0077] The measurement system is initialized, and the optical illumination unit, the double-field-of-view imaging unit, the field-of-view switching unit and the data acquisition control unit are started. The measurement range of the large-field-of-view camera, the resolution of the small-field-of-view camera, the moving step of the high-precision electric translation stage, the flashing frequency of the high-frequency LED light source and other parameters are determined, the optical axes of the small-field-of-view lens and the large-field-of-view lens are ensured to be coincident, and the switchable mirror is set to the initial state to make the light enter the small-field-of-view camera.

[0078] The trigger module drives the second field-of-view imaging module to scan the sampling space, and detects whether the wind-blown snow particles exist by using the interframe difference processing of the high-frame-rate continuous image, and when there is no wind-blown snow particle in the sampling space, the first field-of-view imaging module and the exposure are not started.

[0079] When the small field of view imaging camera detects the wind blown snow particles appearing in the sampling space, the trigger module transmits a high-precision synchronous trigger pulse to the exposure driving module, starts the large field of view imaging camera and the high repetition frequency LED light source, and realizes the synchronous exposure of the wind blown snow particles in the double fields of view.

[0080] Under the rapid exposure of the high repetition frequency LED light source, the large field of view imaging camera simultaneously obtains the distribution image of the wind blown snow particles in the large field of view at an acquisition rate of not less than 5 frames / s.

[0081] While the large field of view camera is working, the small field of view camera continues to measure the particles, and the high-precision electric translation table automatically adjusts the working distance of the small field of view camera according to the distance information of the particles and the camera, and optimizes the focusing effect.

[0082] The image acquisition module time-pairs and encodes the image data, and then transmits the image data to the data processing unit in real time through the image transmission module.

[0083] The data processing unit performs background separation processing under the control of the upper computer software, binarizes the wind blown snow particle image, identifies and extracts the wind blown snow particles, and according to the positional correspondence of the particles in different fields of view, associates the diameter, contour, speed and other parameters to form complete wind blown snow particle measurement data. The fused data are stored and analyzed, and the measurement results can be displayed in an intuitive manner by using data visualization technology, which is convenient for subsequent research and application.

[0084] For the continuous images obtained by the large / small field of view imaging cameras, the time sequence matching of the wind blown snow particles is realized by using the microphysical parameters, and the motion speed of the wind blown snow particles and the wide-range particle speed field vector distribution are obtained according to the motion trajectory of the wind blown snow particles between continuous frames.

[0085] For the high-definition images obtained by the small field of view imaging camera, including but not limited to the calculation of the shape, size, position, speed and other microphysical parameters of the wind blown snow particles at different angles by using the mathematical morphology method, including but not limited to the tracking of the trajectory by using the PTV algorithm;

[0086] For the continuous images obtained by the large field of view imaging camera, including but not limited to the determination of the size and overlap rate of the interrogation window according to the size of the measurement region and the motion speed of the particles by using the PIV method, and the obtaining of the speed field distribution characteristics of the wind blown snow particles in the large field of view.

[0087] With the continuous movement of snow particles blown by the wind, the measurement system continuously performs the above measurement process. When the particles leave the current field of view range, the next possible particle position is predicted according to the direction and speed of the particle movement. The angle of the switchable mirror is adjusted by the algorithm control system to switch the field of view to the predicted position, so that the measurement system can timely capture new particles, and realize continuous and adaptive measurement. The relative position of the small field of view and the large field of view can also be changed by manually controlling the high-precision electric translation stage to focus on the detail information of the blown snow in different areas. During the entire measurement process, the system parameters can be dynamically adjusted according to the actual measurement situation to improve the measurement accuracy and efficiency.

[0088] The above-described embodiments are only descriptions of the preferred modes of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. An adaptive imaging and measurement system for windblown snow particles based on dual-field-of-view fusion, characterized in that, include: Optical illumination unit, dual-field-of-view imaging unit, field-of-view switching unit, data acquisition and control unit, and data processing unit; The optical illumination unit is used to illuminate the sampling space; The dual-field-of-view imaging unit is used to perform dual-field-of-view imaging of windblown snow particles. The field-of-view switching unit is used to control the dual-field-of-view imaging unit to switch and adjust the field of view; The data acquisition and control unit is used to control the optical illumination unit and the dual-field imaging unit to acquire wind-blown snow particle image data; The data processing unit is used to process and display the windblown snow particle image data; The optical illumination unit includes: a first illumination module and a second illumination module; The first lighting module is used to provide a high repetition rate LED light source for extracting the particle velocity field; The second lighting module is used to provide a constant-on LED light source for real-time continuous tracking and measurement of windblown snow particles; The first illumination module and the second illumination module are located on the same side of the target imaging field of view; The dual-field-of-view imaging unit includes: a first field-of-view imaging module and a second field-of-view imaging module; The first field-of-view imaging module is used to acquire continuous image data of windblown snow particles within the first target range; The second field-of-view imaging module is used to acquire high-resolution continuous images of windblown snow particles within a second target range; wherein the first target range is larger than the second target range; The first field-of-view imaging module is placed perpendicular to the sampling plane, and the second field-of-view imaging module is erected at a preset angle to the first field-of-view imaging module. The optical axes of the first field-of-view imaging module and the second field-of-view imaging module coincide, and the particles observed by both are in the same spatial coordinate system, forming a sampling plane in which the field of view of the first field-of-view imaging module remains unchanged while the field of view of the second field-of-view imaging module is adjustable. The field-of-view switching unit includes: a switchable mirror module and a translation device; The switchable mirror module is used to integrate the optical paths of the first field-of-view imaging module and the second field-of-view imaging module into the same main optical axis. The translation device is used to mount the second field-of-view imaging module and adjust the working distance of the second field-of-view imaging module; The switchable reflector module is mounted on the optical axis of the first field-of-view imaging module and the second field-of-view imaging module, and its angle is controlled by a motor to achieve dynamic switching of the light reflection path.

2. The adaptive imaging and measurement system for windblown snow particles based on dual-field-of-view fusion according to claim 1, characterized in that, The data acquisition and control unit includes: a trigger module, an exposure drive module, an image acquisition module, and an image transmission module; The triggering module is used to trigger the first field-of-view imaging module to start acquiring image data when the second field-of-view imaging module detects that a particle has passed by. The exposure driving module is used to synchronously start the first illumination module when the first field-of-view imaging module starts acquiring image data; The image acquisition module is used to perform time pairing and encoding on the image data acquired by the first field-of-view imaging module and the image data acquired by the second field-of-view imaging module, and then transmit the encoded image data to the data processing unit in real time through the image transmission module.

3. The adaptive imaging and measurement system for windblown snow particles based on dual-field-of-view fusion according to claim 1, characterized in that, The data processing unit includes: a preprocessing module and a matching module; The preprocessing module is used to preprocess the image data of the windblown snow particles and, based on the preprocessed image, obtain the microphysical parameters of the windblown snow particles in different fields of view; wherein the microphysical parameters include: diameter, profile, and velocity. The matching module is used to achieve temporal matching of windblown snow particles using the microphysical parameters, and to obtain the motion velocity of windblown snow particles and the large-scale particle velocity field vector distribution based on the motion trajectory of windblown snow particles between consecutive frames.

4. The adaptive imaging and measurement system for windblown snow particles based on dual-field-of-view fusion according to claim 3, characterized in that, The preprocessing module preprocesses the windblown snow particle image data, including: The image data of the blown snow particles is subjected to background separation and binarization processing to identify and extract the blown snow particles. The trajectory tracking and velocity calculation of the blown snow particles are realized through particle matching algorithm.

5. The adaptive imaging and measurement system for windblown snow particles based on dual-field-of-view fusion according to claim 3, characterized in that, The data processing unit further includes: a display module; The display module is used to display the microphysical parameters and motion trajectory of windblown snow particles using data visualization technology.

6. A method for adaptive imaging measurement of windblown snow particles based on dual-field-of-view fusion, characterized in that, The method of using the adaptive imaging measurement system for windblown snow particles based on dual-field-of-view fusion as described in any one of claims 1-5 includes: Initialize the measurement system and start the optical illumination unit, dual-field imaging unit, field-of-view switching unit, and data acquisition and control unit; The trigger module drives the second field-of-view imaging module to scan the sampling space and uses inter-frame difference processing of high frame rate continuous images to detect the presence of windblown snow particles. When there are no windblown snow particles in the sampling space, the first field-of-view imaging module and exposure are not activated. When the second field-of-view imaging module detects wind-blown snow particles in the sampling space, the triggering module will transmit a synchronous trigger pulse to the exposure driving module, start the first field-of-view imaging module and the first illumination module, realize the synchronous exposure of wind-blown snow particles in the dual fields of view, and obtain the distribution image of wind-blown snow particles in the large field of view. After the second field-of-view imaging module detects the particles, the system sends a trigger signal to start the large field-of-view camera to begin image acquisition. The first illumination module flashes at a set frequency to illuminate the particles within the large field of view, and the large field-of-view camera captures multiple frames of particle images. While the first field-of-view imaging module is working, the second field-of-view imaging module continues to measure the particles. The translation device automatically adjusts the working distance of the second field-of-view imaging module based on the distance information between the particles and the camera to optimize the focusing effect. The data processing unit analyzes large field-of-view particle images to obtain the velocity field distribution of windblown snow particles; it analyzes small field-of-view particle images to obtain the diameter, outline, and velocity parameters of the particles; and it performs fusion processing based on the positional correspondence of particles in different fields of view, storing and analyzing the fused data. As the snow particles continue to move, when a particle leaves the current field of view, the position of the next possible particle is predicted based on the particle's direction of motion and speed. The angle of the switchable reflector is adjusted by the control system to switch the field of view to the predicted position, thus achieving continuous and adaptive measurement.

7. The adaptive imaging measurement method for windblown snow particles based on dual-field-of-view fusion according to claim 6, characterized in that, Initializing the measurement system and activating the optical illumination unit, dual-field-of-view imaging unit, field-of-view switching unit, and data acquisition and control unit includes: Determine the measurement range of the first field-of-view imaging module, the resolution of the second field-of-view imaging module, the movement step size of the translation device, and the illumination parameters of the first illumination module. Ensure that the optical axes of the second field-of-view imaging module and the first field-of-view imaging module are aligned, and set the switchable reflector to its initial state to allow light to enter the second field-of-view imaging module.

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