Wind-blown snow particle adaptive imaging measurement system and method based on dual-view-field fusion

Abstract

The invention relates to a wind-blown snow particle adaptive imaging measurement system and method based on dual-view-field fusion. The system comprises an optical illumination unit, a dual-view-field imaging unit, a view field switching unit, a data acquisition control unit and a data processing unit. The optical illumination unit is used for illuminating the sampling space; the double-view-field imaging unit is used for performing double-view-field imaging on the snow particles blown by the wind; the view field switching unit is used for controlling the dual-view-field imaging unit to perform view field switching and adjustment; the data acquisition control unit is used for controlling the optical illumination unit and the double-view-field imaging unit and acquiring image data of snow particles blown by wind; and the data processing unit is used for processing and displaying the wind-blown snow particle image data. The method is developed on the basis of large-view-field and small-view-field area-array cameras, and important data support can be provided for atmospheric scientific research, snow blowing field observation, artificial weather influence and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of meteorological monitoring, and in particular to a self-adaptive imaging measurement system and method for blowing snow particles based on dual-field fusion, which is applicable to multi-parameter dynamic detection of blowing snow particles in a complex wind field environment. Background Art

[0002] The phenomenon of blowing snow is widely distributed in cold regions and has a significant impact on fields such as transportation, power infrastructure, and agricultural production. Accurately measuring parameters such as the velocity, particle size, and morphology of blowing snow particles is crucial for understanding the formation mechanism of blowing snow, predicting its hazards, and formulating effective protection strategies. The Snow Particle Counter (SPC) can directly measure the microscopic characteristics of blowing snow, but it can only obtain the scale and quantity information of blowing snow particles in a very small sampling space. In order to obtain the particle scale velocity distribution information in a larger space range, some scholars have currently applied the Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV) technologies to the measurement of blowing snow in different field of view ranges. However, the above measurement methods have limitations. It is difficult for a single field of view to balance the wide-area measurement of the particle velocity field and the high-precision measurement of particle diameter and morphology. Although the large field of view measurement can obtain the particle velocity field, there are deficiencies in the measurement accuracy of particle diameter and morphology; although the small field of view measurement can accurately measure the particle diameter and morphology, it cannot effectively cover a large range for particle velocity field measurement. Moreover, the fixed focal length system is difficult to adapt to the best focusing requirements of particles with different diameters; and the frequent mechanical field of view switching will also lead to a reduction in time resolution and limited dynamic tracking ability. Therefore, it is of great practical significance to develop a measurement system and method for blowing snow particles that integrates the advantages of large and small fields of view for better observation of the blowing snow phenomenon. Summary of the Invention

[0003] The purpose of the present invention is to provide a self-adaptive imaging measurement system and method for blowing snow particles based on dual-field fusion to solve the problems existing in the above-mentioned prior art. By using the method of combining large-field and small-field imaging and the field of view switching technology, it realizes large-range flow field measurement and small-range particle tracking of the precipitation scene.

[0004] To achieve the above purpose, the present invention discloses a self-adaptive imaging measurement system for blowing snow particles based on dual-field fusion, including: an optical illumination unit, a dual-field imaging unit, a field of view 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-field imaging unit is used for dual-field imaging of blowing snow particles;

[0007] The field-of-view switching unit is used to control the dual-field imaging unit for field-of-view switching and adjustment;

[0008] The data acquisition and control unit is used to control the optical illumination unit and the dual-field imaging unit to acquire blowing snow particle image data;

[0009] The data processing unit is used to process and display the blowing snow particle image data.

[0010] Optionally, the optical illumination unit includes: a first illumination module and a second illumination module;

[0011] The first illumination module is used to provide a high-repetition-rate LED light source for extracting the particle velocity field;

[0012] The second illumination module is used to provide a constant-on LED light source for real-time continuous tracking measurement of blowing 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-field imaging unit includes: a first field-of-view imaging module and a second field-of-view imaging module;

[0015] The first field-of-view imaging module is used to acquire continuous image data of blowing snow particles in a first target range;

[0016] The second field-of-view imaging module is used to acquire high-definition continuous images of blowing snow particles in a second target range; wherein, the first target range is larger than the second target range;

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

[0018] Optionally, the field-of-view switching unit includes: a switchable mirror module and a translation device;

[0019] 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;

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

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

[0022] Optionally, the data acquisition and control unit includes: a trigger module, an exposure driving module, an image acquisition module, and an image transmission module;

[0023] The trigger 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 passes by;

[0024] 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;

[0025] 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.

[0026] Optionally, the data processing unit includes: a preprocessing module, a matching module;

[0027] The preprocessing module is used to preprocess the blowing snow particle image data, and based on the preprocessed image, obtain the microphysical parameters of the blowing snow particles in different fields of view; wherein the microphysical parameters include: diameter, contour, speed;

[0028] The matching module is used to realize the timing matching of the blowing snow particles by using the microphysical parameters, and obtain the movement speed of the blowing snow particles and the large-scale particle velocity field vector distribution according to the movement trajectories of the blowing snow particles between consecutive frames.

[0029] Optionally, the preprocessing performed by the preprocessing module on the blowing snow particle image data includes:

[0030] Performing background separation processing and binarization processing on the blowing snow particle image data, identifying and extracting the blowing snow particles, and realizing the trajectory tracking and speed calculation of the blowing snow particles through a particle matching algorithm.

[0031] Optionally, the data processing unit further includes: a display module;

[0032] The display module is used to display the microphysical parameters and movement trajectories of the blowing snow particles by using data visualization technology.

[0033] To achieve the above object, the present invention also discloses an adaptive imaging measurement method for blowing snow particles based on dual-field fusion, including:

[0034] 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;

[0035] The trigger module drives the second-field imaging module to scan the sampling space, and uses the inter-frame difference processing of high-frame-rate continuous images to detect whether there are blowing snow particles. When there are no blowing snow particles in the sampling space, the first-field imaging module and exposure are not started;

[0036] When the second-field imaging module detects that there are blowing snow particles in the sampling space, the trigger module transmits a synchronous trigger pulse to the exposure drive module to start the first-field imaging module and the first illumination module, realizing the synchronous exposure of the blowing snow particles in the dual fields, and obtaining the distribution image of the blowing snow particles in the large field of view;

[0037] After the second-field imaging module detects the particles, the system sends a trigger signal to start the large-field camera to start 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 camera takes multiple frames of particle images;

[0038] While the first-field imaging module is working, the second-field imaging module continues to measure the particles. The translation device automatically adjusts the working distance of the second-field imaging module according to the distance information between the particles and the camera to optimize the focusing effect;

[0039] The data processing unit analyzes the large-field particle images to obtain the velocity field distribution of the blowing snow particles; analyzes the small-field particle images to obtain the diameter, contour, and velocity parameters of the particles; performs fusion processing based on the position correspondence relationship of the particles in different fields of view, and stores and analyzes the fused data;

[0040] As the blowing snow particles continue to move, when the particles leave the current field-of-view range, predict the position where the next possible particles may appear according to the movement direction and speed of the particles, and adjust the angle of the switchable mirror through the control system to switch the field of view to the predicted position to achieve continuous and adaptive measurement.

[0041] Optionally, initializing the measurement system and starting the optical illumination unit, dual-field imaging unit, field-of-view switching unit, and data acquisition and control unit includes:

[0042] Determine the measurement range of the first-field imaging module, the resolution of the second-field imaging module, the moving step of the translation device, and the illumination parameters of the first illumination module, ensure that the optical axes of the second-field imaging module and the first-field imaging module coincide, and set the switchable mirror to the initial state so that the light enters the second-field imaging module.

[0043] The beneficial effects of the present invention are as follows:

[0044] The adaptive imaging measurement system and method for blowing snow particles based on dual-field fusion proposed by the present invention realizes high-precision measurement of blowing snow particle parameters through the large and small field of view fusion technology: the large field of view camera is responsible for measuring the global particle velocity field, and the small field of view camera focuses on the refined detection of particle size and shape. The two cooperate to improve the parameter measurement accuracy; an adaptive field of view switching mechanism is adopted, and the large field of view camera is driven based on the real-time detection results of the small field of view, and the field of view is dynamically adjusted through a switchable mirror, significantly enhancing the measurement flexibility and efficiency. At the same time, the coaxial optical axis design enables the large and small fields of view to share the coordinate system, avoiding the problem of trajectory breakage 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 microscopic parameter measurement. Description of the Drawings

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0046] Figure 1 It is a block diagram of a system for adaptive imaging measurement of blowing snow particles based on dual-field fusion according to an embodiment of the present invention;

[0047] Figure 2 It is an imaging schematic diagram according to an embodiment of the present invention;

[0048] Figure 3 It is a flowchart of the working process of the method for adaptive imaging measurement of blowing snow particles based on dual-field fusion according to an embodiment of the present invention. Detailed Embodiments

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0050] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

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

[0052] Among them, the optical illumination unit is used to illuminate the sampling space; the dual-field imaging unit is used to perform dual-field imaging on the blowing snow particles; the field-of-view switching unit is used to control the field-of-view switching and adjustment of the dual-field imaging unit; the data acquisition and control unit is used to control the optical illumination unit and the dual-field imaging unit and collect the image data of the blowing snow particles; the data processing unit is used to process and display the image data of the blowing snow particles.

[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 measurement to extract the particle velocity field; the constant-on LED light source provides illumination for small-field measurement to achieve real-time continuous tracking measurement of the blowing snow particles.

[0056] Furthermore, the dual-field 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 obtain continuous images of blowing snow particles in a large range, and the small-field-of-view imaging camera is used to obtain high-definition continuous images of blowing snow particles in a small range.

[0059] In the dual-field imaging unit, the large-field-of-view imaging camera is placed perpendicular to the sampling plane, and the small-field-of-view imaging camera is cross-mounted with the large-field-of-view imaging camera at a preset angle. Its relative position depends on the optical path angle of the switchable mirror, and the optical axes of the large-field-of-view imaging camera and the small-field-of-view imaging camera are strictly coincident to ensure that the particles observed by both are in the same space coordinate system, avoiding spatial registration errors after field-of-view switching. The high-repetition-rate LED light source and the constant-on LED light source are located on the same side of the sampling plane and are used to illuminate the sampling space. The dual-field imaging unit images the blowing snow particles by receiving scattered and reflected light. The flashing frequency of the high-repetition-rate LED light source is adjustable to illuminate the particles in coordination with the camera frame rate to avoid motion trailing. The imaging optical path is as Figure 2 shown.

[0060] The large field of view imaging camera uses a large aperture lens, with an imaging range of 1m×1m and a maximum frame rate of 40 frames per second, and is used for global particle velocity field measurement; the small field of view imaging camera uses a small aperture lens, with an imaging range of 0.1m×0.1m and a maximum frame rate of 1000 frames per second, and is used for refined 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, forming a sampling plane with an unchanged large field of view and an adjustable small field of view. The angle between the main axes of the large / small field of view imaging cameras is adjustable within the range of 20° to 120°, and the angle depends on the optical path angle of the switchable mirror.

[0061] The exposure time of the large field of view imaging camera depends on the lighting duration of the high-repetition-rate LED light source, and single-frame single-exposure and single-frame multi-exposure methods can be used. The single-exposure duration is adjustable within the range of 1μs to 1ms, and the exposure interval time is adjustable within the range of 1μs to 1ms.

[0062] When the small field of view imaging camera detects blowing snow particles in the field of view, it starts the large field of view imaging camera to work for high-precision synchronous exposure. The high-precision clock manager outputs a high-precision pulse signal, and the synchronous trigger delay does not exceed 10ns.

[0063] Furthermore, the field of view switching unit includes: a switchable mirror module and a translation device;

[0064] Specifically, in this embodiment, the translation device uses a high-precision electric translation stage; the switchable mirror module uses a coated beam splitter or a switchable mirror group, which 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 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 and small field of view lenses, and the angle is driven and controlled by a motor to realize the dynamic switching of the light reflection path, ensuring rapid adjustment of the field of view. The high-precision electric translation stage carries the small field of view camera, with a moving accuracy of 0.5mm and a maximum stroke of 100mm, and is used to adjust the working distance of the camera in real time to optimize focusing.

[0066] Furthermore, the data acquisition and control unit includes: a trigger module, an exposure drive module, an image acquisition module, and an image transmission module;

[0067] The trigger module is used 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 has passed by;

[0068] The exposure drive module is used to synchronously start the first lighting module when the first field of view imaging module starts collecting image data;

[0069] The image acquisition module is used to perform time pairing and encoding on 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.

[0070] Further, the data processing unit includes: a preprocessing module and a matching module;

[0071] The preprocessing module is used to preprocess the blowing snow particle image data, and based on the preprocessed image, obtain the microphysical parameters of the blowing snow particles in different fields of view; where the microphysical parameters include: diameter, contour, and velocity;

[0072] The matching module is used to achieve the timing matching of the blowing snow particles by using the microphysical parameters, and based on the movement trajectories of the blowing snow particles between consecutive frames, obtain the movement speed of the blowing snow particles and the vector distribution of the particle speed field in a large range.

[0073] Further, the preprocessing of the blowing snow particle image data by the preprocessing module includes:

[0074] Background separation processing, binarize the blowing snow particle image, identify and extract the blowing snow particles, and realize the trajectory tracking and speed calculation of the blowing snow particles through the particle matching algorithm.

[0075] Further, the data processing unit further includes: a display module; the display module is used to display the microphysical parameters and movement trajectories of the blowing snow particles by using data visualization technology.

[0076] This embodiment also discloses an adaptive imaging measurement method for blowing snow particles based on dual-field fusion, as Figure 3 shown, including the following steps:

[0077] Initialize the measurement system, start the optical lighting unit, dual-field imaging unit, field of view switching unit, and data acquisition control unit. Determine parameters such as 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, and the flashing frequency of the high-repetition-rate LED light source, ensure that the optical axes of the small field of view lens and the large field of view lens coincide, and set the switchable mirror 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 uses the inter-frame difference processing of high-frame-rate continuous images to detect whether there are blowing snow particles. When there are no blowing snow particles 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 blowing snow particles in the sampling space, the trigger module transmits a high-precision synchronous trigger pulse to the exposure drive module to start the large field of view imaging camera and the high-repetition rate LED light source, realizing the synchronous exposure of blowing snow particles in the dual fields of view.

[0080] Under the rapid exposure of the high-repetition rate LED light source, the large field of view imaging camera obtains the distribution image of blowing snow particles in the large field of view at a collection rate of not less than 5 frames per second.

[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 stage automatically adjusts the working distance of the small field of view camera according to the distance information between the particles and the camera to optimize the focusing effect.

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

[0083] Under the control of the host computer software, the data processing unit performs background separation processing, binarizes the blowing snow particle image, identifies and extracts the blowing snow particles. According to the position correspondence relationship of the particles in different fields of view, parameters such as diameter, contour, and speed are correlated to form complete measurement data of blowing snow particles. The fused data is stored and analyzed, and data visualization technology can be used to display the measurement results in an intuitive way for subsequent research and application.

[0084] For the continuous images obtained by the large / small field of view imaging cameras, the microphysical parameters are used to achieve the temporal matching of blowing snow particles. According to the movement trajectories of blowing snow particles between consecutive frames, the movement speed of blowing snow particles and the vector distribution of particle speed fields in a large range are obtained.

[0085] For the high-definition images obtained by the small field of view imaging camera, including but not limited to using mathematical morphology methods, microphysical parameters such as the shape, size, position, and speed of blowing snow particles at different angles are calculated, including but not limited to tracking trajectories through the PTV algorithm;

[0086] For the continuous images obtained by the large field of view imaging camera, including but not limited to using the PIV method, the size of the interrogation window and the overlap rate are determined according to the size of the measurement area and the movement speed of the particles, and the velocity field distribution characteristics of blowing snow particles in the large field of view are obtained.

[0087] As the snow particles blown by the wind continue to move, the measurement system continuously performs the above measurement process. When a particle leaves the current field of view, the position where the next possible particle may appear is predicted based on the movement direction and speed of the particle. The angle of the switchable mirror is adjusted through the algorithm control system to switch the field of view to the predicted position, enabling the measurement system to promptly capture new particles and achieve continuous and adaptive measurement. It is also possible to manually control the high-precision electric translation stage to change the relative position of the small field of view and the large field of view to focus on the detailed information of snow blowing in different regions. 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 embodiments described above are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An adaptive imaging measurement system for blowing snow particles based on dual-field-of-view fusion, characterized in that, Including: An optical illumination unit, a dual-field imaging unit, a field-of-view switching unit, a data acquisition control unit, and a data processing unit; The optical illumination unit is used to illuminate the sampling space; The dual-field imaging unit is used to perform dual-field imaging on the blowing snow particles; The field-of-view switching unit is used to control the field-of-view switching and adjustment of the dual-field imaging unit; The data acquisition control unit is used to control the optical illumination unit and the dual-field imaging unit and acquire the blowing snow particle image data; The data processing unit is used to process and display the blowing snow particle image data.

2. The adaptive imaging measurement system for blowing snow particles based on dual-field-of-view fusion according to claim 1, wherein The optical illumination unit includes: a first illumination module and a second illumination module; The first illumination module is used to provide a high-repetition-rate LED light source for extracting the particle velocity field; The second illumination module is used to provide a constant-on LED light source for real-time continuous tracking measurement of the blowing snow particles; The first illumination module and the second illumination module are located on the same side of the target imaging field of view.

3. The snow drift particle adaptive imaging measurement system based on dual field of view fusion according to claim 2, wherein The dual-field 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 the blowing snow particles in the first target range; The second field-of-view imaging module is used to acquire high-definition continuous images of the blowing snow particles in the 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, the second field-of-view imaging module is cross-mounted with the first field-of-view imaging module at a preset angle, and the optical axes of the first field-of-view imaging module and the second field-of-view imaging module coincide. The particles observed by both are in the same spatial coordinate system, forming a sampling plane with the field of view of the first field-of-view imaging module unchanged and the field of view of the second field-of-view imaging module adjustable.

4. The adaptive imaging measurement system for blowing snow particles based on dual-field-of-view fusion according to claim 3, wherein 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 carry the second field-of-view imaging module and adjust the working distance of the second field-of-view imaging module; The switchable mirror module is installed on the optical axes of the first field-of-view imaging module and the second field-of-view imaging module, and the angle is driven and controlled by a motor to realize the dynamic switching of the light reflection path.

5. The adaptive imaging measurement system for blowing snow particles based on dual field of view fusion according to claim 3, characterized in that The data acquisition control unit includes: a trigger module, an exposure drive module, an image acquisition module, and an image transmission module; The trigger 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 passes by; The exposure drive 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.

6. The snow particle adaptive imaging measurement system based on dual field of view fusion according to claim 3, wherein The data processing unit includes: a preprocessing module, a matching module; The preprocessing module is used to preprocess the image data of the blowing snow particles, and based on the preprocessed image, obtain the microphysical parameters of the blowing snow particles in different fields of view; wherein the microphysical parameters include: diameter, contour, and velocity. The matching module is used to achieve the temporal matching of the blowing snow particles by using the microphysical parameters, and according to the movement trajectories of the blowing snow particles between consecutive frames, obtain the movement speed of the blowing snow particles and the vector distribution of the particle speed field in a large range.

7. The adaptive imaging measurement system for blowing snow particles based on dual-field-of-view fusion according to claim 6, wherein The preprocessing performed by the preprocessing module on the image data of the blowing snow particles includes: Performing background separation processing and binarization processing on the image data of the blowing snow particles, identifying and extracting the blowing snow particles, and realizing the trajectory tracking and speed calculation of the blowing snow particles through a particle matching algorithm.

8. The adaptive imaging measurement system for blowing snow particles based on dual field of view fusion according to claim 6, wherein The data processing unit further includes: a display module; The display module is used to display the microphysical parameters and movement trajectories of the blowing snow particles by using data visualization technology.

9. An adaptive imaging measurement method for blown snow particles based on dual-field fusion, characterized in that, Applying the blowing snow particle adaptive imaging measurement system based on dual-field fusion as described in any one of claims 1-8, the method includes: Initializing the measurement system, and starting the optical lighting unit, the dual-field imaging unit, the field-of-view switching unit, and the data acquisition control unit; The trigger module drives the second field-of-view imaging module to scan the sampling space, and uses the inter-frame difference processing of high-frame-rate continuous images to detect whether there are blowing snow particles. When there are no blowing snow particles in the sampling space, the first field-of-view imaging module and the exposure are not started. When the second field-of-view imaging module detects that there are blowing snow particles in the sampling space, the trigger module transmits a synchronous trigger pulse to the exposure drive module, starts the first field-of-view imaging module and the first lighting module, realizes the synchronous exposure of the blowing snow particles in the dual fields of view, and obtains the distribution image of the blowing 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 camera to start image acquisition. The first lighting module flashes at a set frequency to illuminate the particles within the large field of view, and the large-field camera takes 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, and the translation device automatically adjusts the working distance of the second field-of-view imaging module according to the distance information between the particles and the camera to optimize the focusing effect. The data processing unit analyzes the large-field particle images to obtain the distribution of the blowing snow particle speed field; analyzes the small-field particle images to obtain the diameter, contour, and speed parameters of the particles; performs fusion processing based on the position correspondence relationship of the particles in different fields of view, and stores and analyzes the fused data. As the blowing snow particles continue to move, when the particles leave the current field-of-view range, predict the position where the particles may appear next according to the movement direction and speed of the particles, and adjust the angle of the switchable mirror through the control system to switch the field of view to the predicted position to achieve continuous and adaptive measurement.

10. The method for adaptive imaging measurement of blowing snow particles based on dual-field-of-view fusion according to claim 9, wherein Initializing the measurement system, and starting the optical lighting unit, the dual-field imaging unit, the field-of-view switching unit, and the data acquisition 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 moving step 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 coincide, and set the switchable mirror to the initial state to allow light to enter the second field of view imaging module.

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