Sighting and field-of-view information acquisition device and spectral field-of-view range determination method and device

Abstract

The invention discloses a sighting and field-of-view information acquisition device and a spectrum field-of-view range determination method and device, and relates to the technical field of remote sensing. Wherein the sighting and view field information acquisition device comprises a controller, a laser sighting and distance measuring module and an optical image acquisition module which are arranged on a holder; wherein the controller is used for responding to an initial signal triggered when the unmanned aerial vehicle collects a non-imaging spectrum, and generating a control signal; the laser sighting and ranging module is used for emitting laser to a sight area according to the control signal; the optical image acquisition module is used for acquiring a ground image of the target area according to a control signal; the laser sighting and ranging module is also used for collecting the height difference between the unmanned aerial vehicle and the target area to obtain laser ranging; and the controller is also used for taking the ground image and the laser ranging as view field information. By implementing the technical scheme provided by the invention, the reliability of spectral data acquisition can be improved.

Description

Technical Field

[0001] The invention relates to the field of remote sensing technology, and in particular to a sighting and field of view information acquisition device, and a method and device for determining a spectral field of view range. Background Art

[0002] Non-imaging spectral acquisition technology plays an important role in the field of remote sensing applications. This technology can be used for object identification, data calibration, and precision analysis by collecting the energy reflection characteristics of objects in different spectral bands. With the development of technology, it has gradually become an important acquisition method to carry non-imaging spectrometers on UAV platforms for data acquisition. This method can not only reduce the interference of mixed spectra during ground acquisition, but also obtain a wider range of acquisition data.

[0003] At present, when drones are equipped with non-imaging spectrometers to collect data, they mainly set the flight route and collection points, and hover to collect data after reaching the specified location. During the collection process, the ground control station sends a collection command to trigger the spectrometer to obtain the spectral data of the target area. In order to assist in determining the collection location, some systems will be equipped with camera equipment to take pictures of the target area while collecting the spectrum.

[0004] However, due to the high altitude of the UAV and the fluctuation of its attitude during the acquisition process, there are height and plane position differences between the operator and the aircraft, making it difficult for ground operators to accurately determine the actual spectral acquisition area. Especially when performing side-view acquisition, the uncertainty of the target area positioning is further increased, which may result in the spectral data collected not being the data of the expected target area, reducing the reliability and controllability of the collected data. Summary of the invention

[0005] The present invention provides a sighting and field of view information collection device, a spectral field of view range determination method and device, which effectively solve the technical problem in the prior art that it is difficult to accurately judge the actual spectral collection area due to the high flying altitude and posture fluctuation of the unmanned aerial vehicle, and improve the reliability and controllability of spectral data collection.

[0006] In a first aspect of the present invention, there is provided a sighting and field of view information acquisition device, comprising a controller disposed on a pan / tilt platform, a laser sighting and ranging module, and an optical image acquisition module; The controller is used to respond to a start signal triggered when the drone collects non-imaging spectra and generate a control signal; The laser aiming and ranging module is used to emit laser at the sight area according to the control signal, so that the fiber optic probe of the drone spectrometer aims at the target area according to the light spot generated by the target area; The optical image acquisition module is used to acquire the ground image of the target area according to the control signal; The laser aiming and ranging module is also used to collect the height difference between the fiber optic probe of the drone spectrometer and the target area to obtain the laser ranging; The controller is also used to use the ground image and the laser ranging as field of view information.

[0007] In a second aspect of the present invention, a method for determining a spectral field of view range is provided, comprising: Acquire the field of view information when the drone collects non-imaging spectrum, the field of view information sighting and field of view information acquisition device collects, including the ground image of the target area and the laser ranging between the drone and the target area; The acquisition mode of the UAV is acquired, and the spectral field of view range is determined based on the acquisition mode and the field of view information.

[0008] In a third aspect of the present invention, a field of view information acquisition module is provided, which is used to acquire field of view information when a drone collects non-imaging spectra, wherein the field of view information is acquired by a sighting and field of view information acquisition device, and includes a ground image of a target area and a laser ranging between the drone and the target area; The field of view range determination module is used to obtain the acquisition mode of the drone and determine the spectral field of view range based on the acquisition mode and the field of view information.

[0009] In a fourth aspect of the present invention, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for determining the spectral field range as described above is implemented.

[0010] In a fifth aspect of the present invention, a non-transitory computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the method for determining the spectral field range as described in any one of the above is implemented.

[0011] In a sixth aspect of the present invention, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned spectral field range determination methods.

[0012] In summary, one or more technical solutions provided in the present invention have at least the following technical effects or advantages: The controller responds to the start signal of the drone when collecting non-imaging spectra and generates a control signal. The laser sighting and ranging module forms a visible light spot in the target area according to the control signal, providing an intuitive sighting reference for ground operators, and at the same time obtains the actual height difference between the drone and the target area. The optical image acquisition module collects the ground image of the target area according to the control signal, and the controller uses the ground image and laser ranging as the field of view information, thereby realizing accurate positioning of the spectrum collection area and recording of the field of view information. The above technical solution provides real-time visible target area indication through laser sighting, combines height measurement and image acquisition to form complete field of view information, effectively solves the technical problem in the prior art that it is difficult to accurately judge the actual spectrum collection area due to the high flying altitude of the drone and the existence of attitude fluctuations, and improves the reliability of spectral data acquisition. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of a sighting and field of view information acquisition device provided by an embodiment of the present invention.

[0015] Figure 2 It is a flow chart of a method for determining a spectral field of view range provided by an embodiment of the present invention.

[0016] Figure 3 It is a schematic diagram of program solution provided by an embodiment of the present invention.

[0017] Figure 4 It is a structural schematic diagram of a spectral field range determination device provided by an embodiment of the present invention.

[0018] Figure 5 It is a structural schematic diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Remote sensing ground non-imaging spectrometer is an important device in remote sensing scientific research and application. Its working principle is to sample and record the light energy emitted by the ground object within a specific wavelength range. Through the preset spectral resolution, the system can record the energy reflection and absorption characteristics of the target ground object in different spectral bands to form a continuous spectral curve. This spectral curve has important scientific value, because different ground objects will show specific absorption and reflection characteristics on their spectral curves due to differences in physical and chemical properties, which provides a scientific basis for ground object identification and quantitative application.

[0021] In traditional ground-based spectral collection, operators need to hold a fiber or a collector equipped with a fiber and aim it at the target object for collection. This collection mode has obvious limitations: first, due to the height of the personnel or the height of the collection platform, the fiber entrance is usually only 0.5-1.5 meters from the ground. This low collection height easily leads to a small field of view; second, the field of view of the fiber forms a cone, and all light within this cone may be received by the detector. When the field of view is too large or too close to the target, the spectral information of non-target objects will be collected together, resulting in contamination of the spectral data. These problems seriously affect the quality and availability of spectral data.

[0022] In recent years, with the development of drone technology, researchers have developed drone non-imaging spectral acquisition systems to try to overcome the limitations of traditional acquisition methods. The system carries a spectrometer on a rotary-wing drone and performs flight acquisition at a preset altitude and route. This innovative acquisition method brings many advantages: a higher acquisition platform provides a larger field of view and reduces the mixing of impurity spectra; it also provides a new technical approach for spectral scale conversion and bidirectional reflectance distribution function measurement.

[0023] However, the UAV spectral acquisition system also faces new technical challenges. Due to the high flight altitude, fast flight speed and large operating range of UAVs, it is difficult for ground staff to reach the acquisition area in time for on-site confirmation. More importantly, the high flight altitude makes it difficult to accurately locate the observation field, which makes it impossible to effectively grasp key information such as the spatial composition and texture structure of the acquisition target. This situation seriously affects the reliability of spectral data and the accuracy of subsequent applications.

[0024] In terms of determining the field of view, in vertical acquisition mode, it can be estimated through a series of parameters, including the fiber field of view angle, flight altitude, image collector parameters, etc. These parameters can be used to calculate the radius of the field of view projection circle, and the field of view range can be determined in combination with the image resolution. However, in the side-view acquisition mode, due to the more complex observation geometry, it becomes more difficult to determine the field of view range, and often only a rough estimate can be made.

[0025] At present, there are still relatively few non-imaging spectral acquisition systems for drones on the market. Although the existing systems have realized basic spectral acquisition and synchronous photography functions, their functions in field of view extraction are still insufficient, especially the field of view determination problem in the side-view acquisition mode has not been effectively solved. These technical bottlenecks have seriously restricted the application effect and promotion of drone spectral acquisition systems. Therefore, developing a system that can accurately determine the field of view range, especially the side-view acquisition mode, is of great significance to improving the data quality and application effect of drone spectral acquisition.

[0026] Based on the above questions, please refer to Figure 1 , Figure 1 is a schematic diagram of a sighting and field of view information acquisition device provided by an embodiment of the present invention, the sighting and field of view information acquisition device comprising a controller arranged on a pan / tilt platform, a laser sighting and ranging module, and an optical image acquisition module; The controller is used to respond to a start signal triggered when the drone collects non-imaging spectra and generate a control signal.

[0027] The start signal refers to the trigger acquisition signal sent by the flight control system when the drone performs non-imaging spectrum acquisition. In the embodiment of the present invention, it can be understood as a digital level signal automatically generated by the flight control system when the drone reaches the set acquisition position and maintains a stable hovering state, or a level signal converted from a control instruction manually issued by the ground station operator through a remote control device. The start signal is used to notify the controller to start a complete data acquisition process.

[0028] For example, when the drone flies along a pre-planned route, the flight control system can automatically generate a start signal based on the location of the collection point marked on the route. Alternatively, when the operator finds a suitable collection target, he can send a command through the ground station, which is converted by the flight control system to form a start signal. The start signal can be a level signal triggered by a rising edge or a falling edge, or a specific data instruction. The specific form can be selected according to the design requirements of the controller.

[0029] The control signal refers to a set of timing level signals generated by the controller according to a preset timing after receiving the start signal, which is used to coordinate the work of each functional module. In the embodiment of the present invention, it can be understood as a multi-channel timing control level generated by the controller through the internal delay circuit, and these control levels trigger the laser aiming and ranging module and the optical image acquisition module to perform corresponding work tasks in a specific order.

[0030] The laser aiming and ranging module is used to emit laser at the sight area according to the control signal, so that the fiber optic probe of the drone spectrometer can aim at the target area according to the light spot generated by the target area.

[0031] Specifically, in order to solve the problem of difficulty in accurately determining the spectrum collection position during the spectrum collection process of the drone, the laser aiming and ranging module adopts a design scheme of rigid connection between the visible laser emitting device and the optical fiber probe. After receiving the control signal from the controller, the module emits a visible laser beam to the target area through the laser emitting device, forming a clearly visible light spot on the ground, thereby providing an intuitive visual reference for the operator.

[0032] Specifically, the laser aiming and ranging module and the fiber optic probe adopt a rigid connection structure, and through precise adjustment, ensure that the laser beam is strictly parallel to the optical fiber line of sight. The module is installed as close to the optical fiber probe as possible, so that the distance between the laser spot formed on the ground and the ground projection point of the optical fiber is controlled within a range of several millimeters to tens of millimeters. Considering the actual stability and application accuracy requirements of the UAV platform, this slight deviation can be ignored, and the laser spot position can be considered to be the ground projection position of the optical fiber.

[0033] When the control signal triggers the laser aiming and ranging module to work, the laser beam emitted by the module will form a clear light spot in the target area. This light spot can not only help ground operators to grasp the specific location of spectrum collection in real time, but also assist UAV operators to make fine adjustments to ensure that the spectrum data of the expected target is collected. Especially when performing side-view observation, the change in the collection angle will make it more difficult to locate the target, and the importance of the laser aiming function is more prominent at this time.

[0034] Through the above design, the module significantly improves the positioning accuracy during spectral acquisition and improves the controllability of acquisition operations. The operator can observe the acquisition position in real time and adjust the drone position or acquisition parameters in time, avoiding data quality problems caused by acquisition position deviation. At the same time, this visual positioning method also greatly improves the efficiency of field operations and reduces the probability of repeated acquisition.

[0035] The optical image acquisition module is used to acquire ground images of the target area according to the control signal.

[0036] Specifically, the optical image acquisition module uses a high-resolution optical camera, which is installed on the gimbal synchronously with the fiber optic probe and the laser aiming and ranging module. After receiving the control signal from the controller, the module can obtain a high-definition ground image of the target area to record the actual ground conditions at the time of spectrum acquisition.

[0037] Specifically, the optical axis direction of the optical image acquisition module is consistent with that of the optical fiber probe, ensuring that its field of view completely covers the spectrum acquisition area. When the control signal triggers the module to work, the optical camera will collect ground images of the target area, which not only contains the center position of the spectrum acquisition marked by the laser aiming point, but also records the ground object information of the surrounding area, providing an important reference for the subsequent determination of the actual spectrum acquisition range.

[0038] Furthermore, the collected ground images can clearly display key information such as the composition of ground objects, texture distribution characteristics, and terrain features in the target area. This information is of great significance for understanding the representativeness of the collected spectral data, and can help data users accurately judge the ground object characteristics reflected by the spectral curve. For example, through the image, it can be clearly seen whether there are heterogeneous objects within the collection range, or whether the ground object coverage is uniform, which are important factors affecting the quality of spectral data.

[0039] Based on the above embodiment, the optical image acquisition module is also used to acquire a first ground image of the target area after the laser aiming and ranging module is turned on, and to acquire a second ground image of the target area after the laser aiming and ranging module is turned off.

[0040] Specifically, in order to meet different data analysis requirements and improve the application flexibility of ground images, the optical image acquisition module adopts a dual acquisition mode. The module follows the timing preset by the controller and performs image acquisition at two different moments when the laser aiming and ranging modules are in different working states, obtaining two different state images of the same target area.

[0041] Specifically, when the controller triggers a complete acquisition process, the optical image acquisition module first acquires the first ground image with the laser aiming and ranging modules turned on. The image at this time contains the laser aiming point, which clearly marks the ground projection position of the fiber optic probe and provides an important reference for determining the precise position of the spectrum acquisition. Subsequently, the controller sends a signal to turn off the laser, and after the laser is turned off, the optical image acquisition module collects the second ground image again. This image without the laser aiming point fully records the original state of the target area.

[0042] Furthermore, the main purpose of adopting the above-mentioned dual acquisition mode is to meet different data processing requirements. The first ground image with the laser aiming point is mainly used to accurately locate and verify the accuracy of the spectral acquisition position, so that operators and data users can confirm whether the acquisition point position meets the expected requirements. The second ground image without the laser aiming point is used for subsequent image processing and analysis to avoid the interference of the laser point on the original information of the ground object. For example, when it is necessary to extract the spectral characteristics of the ground object within the field of view, the second ground image that is not interfered by the laser can be used for analysis.

[0043] The laser aiming and ranging module is also used to collect the height difference between the fiber optic probe of the drone spectrometer and the target area to obtain the laser ranging.

[0044] Specifically, in order to accurately calculate the spectral field of view and obtain the actual acquisition distance, the laser aiming and ranging module integrates a high-precision laser ranging function. This function measures the actual distance between the drone and the target area in real time by emitting ranging laser to the target area and receiving the reflected signal, thus obtaining more accurate laser ranging data.

[0045] Specifically, when the controller triggers the acquisition process, the laser aiming and ranging module performs the aiming function while also measuring the actual distance from the device to the ground through the built-in laser ranging device. The ranging laser and the aiming laser share the same optical path system to ensure the consistency of the measured position and the acquisition position. After the module receives the laser signal reflected from the ground, it calculates the laser ranging value based on the flight time principle and transmits the value to the controller for recording and storage. This design overcomes the errors caused by relying solely on the calculation of the UAV flight control height. Especially under complex terrain conditions, the traditional flight control height may deviate greatly from the actual acquisition distance.

[0046] Furthermore, the acquisition of laser distance measurement is of great significance for the subsequent accurate calculation of the field of view. In the vertical acquisition mode, the laser distance measurement is directly used as the height value for calculating the field of view; in the side-view acquisition mode, the laser distance measurement is used as the slant distance, and the horizontal distance and vertical height can be accurately calculated in combination with the tilt angle of the gimbal. These parameters are key data for determining the actual field of view of spectral acquisition, and directly affect the accuracy of the field of view calculation.

[0047] The controller is also used to use ground images and laser ranging as field of view information.

[0048] Specifically, after each acquisition process is triggered, the controller will associate and store the ground image acquired by the optical image acquisition module and the laser ranging value measured by the laser aiming and ranging module. The controller also generates a log file (log file) to record key parameters such as the timestamp of the current acquisition, the gimbal attitude angle, the image file name, and the laser ranging value. This organization method ensures the correspondence between all data in the same acquisition process and avoids data confusion and association errors.

[0049] Please refer to Figure 2 , Figure 2The present invention provides a flow chart of a method for determining the spectral field of view range provided by an embodiment of the present invention. The method can be implemented by a computer program, can be implemented by a single-chip microcomputer, or can be run on a spectral field of view range determination system based on a von Neumann system. The computer program can be integrated into an application or run as an independent tool application. Specifically, the method can include the following steps: S101, obtaining the field of view information when the drone collects non-imaging spectra, the field of view information being collected by the above-mentioned sighting and field of view information collection device, including the ground image of the target area and the laser ranging between the drone and the target area.

[0050] Specifically, in order to accurately determine the spectral field of view range, it is first necessary to obtain the field of view information of the drone during the non-imaging spectrum collection process. This information is synchronously collected by the aiming and field of view information collection device during the spectrum collection process, including the ground image and laser ranging data of the target area, providing basic data support for the subsequent field of view range calculation.

[0051] Specifically, the system obtains the field of view information by reading the log file generated by the controller. The log file records the key data of each spectrum acquisition process, including the first ground image with the laser aiming point, the file path of the second ground image without the laser aiming point, and the corresponding laser ranging value. The system first reads the image file path in the log file and loads the corresponding ground image data; at the same time, it extracts the recorded laser ranging value, which reflects the actual distance between the drone and the target area. For the first ground image, the system also needs to locate the position of the laser aiming point. This position information is important for determining the center point of the field of view.

[0052] S102: Acquire the acquisition mode of the drone, and determine the spectral field of view range based on the acquisition mode and field of view information.

[0053] Among them, the acquisition mode refers to the observation method when the spectrum acquisition system carried by the drone obtains the spectrum information of the ground object. In the embodiment of the present invention, it can be understood as two basic acquisition modes determined based on the gimbal attitude angle: vertical acquisition mode and side-view acquisition mode. Among them, the vertical acquisition mode refers to the acquisition method in which the pitch angle of the gimbal is in the range of 88-92 degrees and the optical fiber probe is approximately vertically pointed to the ground; the side-view acquisition mode refers to the acquisition method in which the pitch angle of the gimbal is in other angle ranges and the optical fiber probe is at a certain angle to the ground. This acquisition mode is used to determine the geometric model and calculation method used in the field of view range calculation.

[0054] For example, when the system determines that it is in vertical acquisition mode, the laser ranging value can be directly used as the acquisition height, the field of view range appears as a perfect circle on the ground, and the calculation method is relatively simple; when it is determined to be a side-view acquisition mode, the influence of the observation angle needs to be considered, and the actual vertical and horizontal distances are calculated through trigonometric functions. The field of view range appears as an ellipse on the ground, and the calculation process is relatively complicated. The difference in geometric relationships under different acquisition modes directly affects the shape and size of the field of view range, so accurately identifying the acquisition mode is an important prerequisite for achieving accurate field of view range calculation.

[0055] Based on the above embodiment, as an optional embodiment, in S102: the step of obtaining the collection mode of the drone may further include the following steps: S201. Determine the collection mode of the drone based on the verticality of the gimbal.

[0056] Specifically, in order to accurately distinguish the specific modes of drone spectral acquisition, the system needs to make judgments based on the verticality of the gimbal. Since the geometric relationships under different acquisition modes are significantly different, mode judgment based on the gimbal attitude angle is a simple and effective method. This judgment method makes full use of the existing gimbal attitude information without adding additional hardware equipment.

[0057] Specifically, the system reads the gimbal attitude data from the log file generated by the controller, which contains the pitch angle information of the gimbal at the time of acquisition. Taking into account the errors and jitters in actual operation, the system sets a reasonable angle threshold range, usually 88-92 degrees as the judgment standard. When the pitch angle of the gimbal is within this range, it is judged as a vertical acquisition mode, and the fiber optic probe is approximately vertically pointing to the ground; when the pitch angle of the gimbal exceeds this range, it is judged as a side-view acquisition mode, indicating that the fiber optic probe is at a certain angle to the ground. This judgment method based on angle threshold takes into account the tolerance of actual operation and ensures the reliability of the judgment result.

[0058] S202: If it is determined that the acquisition mode is the vertical acquisition mode, the laser distance measurement is used as the vertical distance.

[0059] S203: If it is determined that the acquisition mode is the oblique acquisition mode, the laser distance measurement is used as the oblique distance.

[0060] For details, please refer to Figure 3 , Figure 3 A schematic diagram of program solution provided by an embodiment of the present invention is shown.

[0061] In order to accurately calculate the field of view in different acquisition modes, the system needs to perform reasonable geometric analysis on the laser distance measurement value. Due to the different geometric relationships between the vertical acquisition mode and the oblique acquisition mode, the interpretation and use of the laser distance measurement value also need to be adjusted accordingly, which is a key link to ensure the accuracy of the field of view calculation.

[0062] Specifically, after the system completes the acquisition mode judgment, it will process the laser ranging value accordingly according to different modes. When it is determined to be a vertical acquisition mode, since the fiber optic probe is approximately vertically pointing to the ground, the distance measured by the laser ranging device can be directly used as the vertical distance (vertical distance) from the drone to the ground. In this case, the projection of the field of view on the ground appears as a perfect circle, and its radius can be directly calculated by trigonometric functions using the vertical distance and the fiber optic field of view angle. When it is determined to be an oblique acquisition mode, the distance measured by the laser ranging device is actually the oblique distance (slant distance) from the drone to the ground. In this case, the system needs to combine the gimbal pitch angle and decompose the slant distance into horizontal distance and vertical height through trigonometric functions. These parameters jointly determine the projection shape and size of the field of view on the ground.

[0063] Based on the above embodiment, as an optional embodiment, for the problem of determining the field of view in the oblique acquisition mode, a reasonable balance needs to be made between calculation accuracy and practicality. Although from a strict geometric optical point of view, when the optical camera has an inclined angle, the field of view projection on the image it acquires should be an ellipse, but considering the characteristics of the actual application scenario and the use of data, the present invention adopts a simplified processing solution.

[0064] Specifically, when processing images in the oblique viewing mode, the system directly uses a perfect circle shape to represent the field of view, without performing complex geometric corrections on the projection deformation. The rationality of this simplified processing is based on the following factors: First, in practical applications, the flight altitude of the drone is usually within tens of meters. In this relatively small altitude range, the image deformation caused by the inclination is relatively small; second, the images acquired by the optical camera are mainly used to assist in determining the type and distribution characteristics of the objects in the target area, and do not require strict geometric accuracy; third, the use of a perfect circle simplified representation can greatly reduce the computational complexity and improve processing efficiency. When determining the field of view, the system still uses the same circular projection method as the vertical acquisition mode, but takes into account the influence of the slant distance when calculating the field of view radius.

[0065] Based on the above embodiment, as an optional embodiment, in S102: the step of determining the spectral field of view range based on the acquisition mode and the field of view information may further include the following steps: S301. Determine the field of view circle radius according to the optical fiber field angle and laser ranging.

[0066] Among them, the fiber field angle refers to the opening angle of the receiving light cone of the fiber optic probe, which is a fixed parameter determined by the numerical aperture of the optical fiber; the field circle radius refers to the radius of the circular area formed by the projection of the spectrum acquisition area on the ground, which is an important parameter for the actual coverage range of the spectrum acquisition. In the embodiment of the present invention, the fiber field angle can be understood as the maximum opening angle that the fiber optic probe can receive the ground reflected light, usually expressed as an angle value, such as 25 degrees; the field circle radius can be understood as the distance from the boundary of the spectrum acquisition coverage area to the center point with the laser aiming point as the center. These parameters are used to determine the actual spatial range of spectral acquisition and provide a spatial reference for data analysis.

[0067] Specifically, the system calculates the radius of the field of view circle through trigonometric functions based on the pre-calibrated fiber field of view angle value and the real-time laser ranging value. In the vertical acquisition mode, the radius of the field of view circle is equal to the product of the laser ranging value and the tangent value of the fiber field of view angle; in the oblique acquisition mode, although the actual projection should be an ellipse, based on the aforementioned simplified processing principle, the same calculation method is still used, that is, the product of the laser ranging value and the tangent value of the fiber field of view angle is used as the radius of the field of view circle. The calculation formula can be expressed as: R=H×tan(θ / 2), where R is the radius of the field of view circle, H is the laser ranging value, and θ is the fiber field of view angle.

[0068] Through the above technical solutions, the system realizes the quantitative description of the field of view and provides an accurate reference for the spatial analysis of spectral data. This calculation method based on the principle of geometric optics not only takes into account the inherent characteristics of the fiber optic probe, but also combines the distance parameters measured in real time, which can accurately reflect the actual coverage under different acquisition conditions. At the same time, this unified calculation method also simplifies the implementation complexity of the system and improves processing efficiency. Especially when it is necessary to quickly evaluate whether the acquisition range meets the research needs, this method can provide an intuitive quantitative reference to help operators make correct judgments.

[0069] S302: Determine the center point of the ground image.

[0070] The center point of the ground image refers to the corresponding point position of the actual position of the spectrum acquisition on the ground image. In the embodiment of the present invention, it can be understood as the pixel coordinate position of the laser aiming point in the first ground image, which identifies the projection center of the optical fiber probe on the ground. This center point is used to determine the specific position of the field of view on the ground image and is the reference point for drawing the field of view.

[0071] Specifically, the system automatically identifies the position of the laser aiming point in the first ground image through image processing methods. Since the laser aiming point usually appears as a high-brightness feature point in the image, the system first grayscales the image, then binarizes it by setting an appropriate brightness threshold, and extracts the high-brightness area. Considering the morphological characteristics of the laser aiming point, the system also needs to perform morphological processing to remove possible noise points, and finally determine the centroid position of the laser point through connected region analysis, and use the pixel coordinates of this position as the center point of the ground image. To improve the reliability of recognition, the system can also verify it in combination with the size, shape and other characteristics of the laser point to exclude other possible high-brightness interference.

[0072] S303, determining the image spatial resolution based on laser ranging.

[0073] Among them, the image spatial resolution refers to the actual ground distance corresponding to a single pixel in the ground image. In the embodiment of the present invention, it can be understood as the ground sample distance (GSD) calculated based on the laser ranging value and the camera parameters, that is, the actual size of a pixel in the image on the ground. This parameter is used to determine the pixel radius of the field of view circle on the ground image, providing a scale reference for the accurate drawing of the field of view range.

[0074] Specifically, the system uses the internal parameters of the camera (including focal length, pixel size) and laser ranging values ​​to calculate the spatial resolution of the image. In the vertical acquisition mode, the spatial resolution is equal to the ratio of the pixel size to the laser ranging value multiplied by the focal length; in the oblique acquisition mode, the scale change caused by the inclination angle also needs to be considered, but based on the aforementioned simplified processing principle, the vertical mode calculation method is also used. The calculation formula can be expressed as: GSD=(P×H) / f, where GSD is the ground sampling distance, P is the camera pixel size, H is the laser ranging value, and f is the camera focal length. This calculation method takes into account the physical characteristics of the imaging system and the influence of the actual observation distance.

[0075] S304, determining the spectral field of view range according to the field of view circle radius, the center point and the image space resolution.

[0076] The spectral field of view refers to the actual observation coverage area of ​​the fiber optic probe on the ground. In the embodiment of the present invention, it can be understood as a circular area drawn on the ground image with the laser aiming point as the center, which represents the actual spatial range and ground object coverage of the spectrum acquisition. This range is used to determine the spatial representativeness of the spectral data and help researchers accurately judge the ground object composition and spatial characteristics of the collected data.

[0077] Based on the above embodiment, as an optional embodiment, in S304: the step of determining the spectral field of view range according to the field of view circle radius, the center point and the image spatial resolution may further include the following steps: S401, generating a mask according to the field of view circle radius, center point and image space resolution.

[0078] The mask refers to a binary image in the form of a two-dimensional matrix, which is used to mark the spatial position information of a specific area in the image. In the embodiment of the present invention, it can be understood as a binary array with the same size as the ground image, where pixels with a value of 1 represent the valid area of ​​spectral acquisition, and pixels with a value of 0 represent the non-acquisition area. This mask is used to accurately identify the spatial range of spectral acquisition and realize the extraction and statistical analysis of ground feature features.

[0079] Specifically, the system first creates an all-zero matrix based on the size of the ground image. Then, the actual ground distance is converted into pixel units, and the conversion formula is: pixel radius = field of view circle radius / image spatial resolution. With the pixel coordinates of the laser aiming point as the center of the circle, the Bresenham circle generation algorithm or the midpoint circle generation algorithm is used to draw a circular boundary on the mask matrix. Next, the area filling algorithm is used to set the pixel value of the inner area of ​​the circle to 1 to form a complete circular mask. During the generation process, the system needs to process the boundary pixels to ensure that the generated circular area has a smooth boundary. At the same time, the intersection of the circular area and the image boundary must be considered to ensure the effectiveness of the mask.

[0080] S402: Generate a spectral field of view range according to the mask.

[0081] Specifically, in order to convert the digital area defined by the mask into a visual spectral field of view, the system needs to synthesize the mask information with the ground image. This processing can not only intuitively display the spatial range of spectral acquisition, but also retain the feature information of the ground object, providing an intuitive spatial reference for the acquisition process.

[0082] Specifically, the system uses image processing methods to draw the field of view on the ground image based on the generated binary mask. First, the system detects the boundary positions of pixels with a value of 1 in the mask and extracts the outline of the circular area. Then, these outline pixels are mapped to the original ground image and the boundaries are drawn using preset display parameters. In order to enhance the visual effect, the system can also perform semi-transparent filling processing on the circular area. The filling color can be selected with a color that has a large contrast with the background, so that the field of view is clearly visible without completely blocking the ground features below. During the processing, the system needs to ensure the consistency of the drawing parameters to ensure that the field of view collected at different times and locations has a unified visual presentation.

[0083] Please refer to Figure 4 , Figure 4 A device for determining a spectrum field range provided by an embodiment of the present invention includes: A field of view information acquisition module, used to acquire field of view information when the drone collects non-imaging spectra, wherein the field of view information is acquired by the sighting and field of view information acquisition device, including a ground image of a target area and a laser ranging between the drone and the target area; The field of view range determination module is used to obtain the acquisition mode of the drone and determine the spectral field of view range based on the acquisition mode and the field of view information.

[0084] On the basis of the above embodiment, as an optional embodiment, the field of view range determination module is also used to determine the acquisition mode of the drone based on the verticality of the gimbal; if the acquisition mode is determined to be a vertical acquisition mode, the laser ranging is used as the vertical distance; if the acquisition mode is determined to be an oblique acquisition mode, the laser ranging is used as the slant distance.

[0085] Based on the above embodiments, as an optional embodiment, the field of view range determination module is also used to determine the field of view circle radius according to the optical fiber field angle and the laser ranging; determine the center point of the ground image; determine the image spatial resolution based on the laser ranging; determine the spectral field of view range according to the field of view circle radius, the center point and the image spatial resolution.

[0086] Based on the above embodiment, as an optional embodiment, the field of view range determination module is further used to generate a mask according to the field of view circle radius, the center point and the image spatial resolution; and generate a spectral field of view range according to the mask.

[0087] Figure 5 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 5 As shown, the electronic device may include: a processor 510, a communication interface 520, a memory 530 and a communication bus 540, wherein the processor 510, the communication interface 520 and the memory 530 communicate with each other through the communication bus 540. The processor 510 may call the logic instructions in the memory 530 to execute the spectral field range determination method.

[0088] In addition, the logic instructions in the above-mentioned memory 530 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0089] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the spectral field range determination method provided by the above-mentioned methods.

[0090] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the spectral field range determination method provided by the above methods.

[0091] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0092] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sighting and field of view information acquisition device, characterized in that: It includes a controller, a laser aiming and ranging module and an optical image acquisition module arranged on the gimbal; The controller is used to respond to a start signal triggered when the drone collects non-imaging spectra and generate a control signal; The laser aiming and ranging module is used to emit laser at the sight area according to the control signal, so that the fiber optic probe of the drone spectrometer aims at the target area according to the light spot generated by the target area; The optical image acquisition module is used to acquire the ground image of the target area according to the control signal; The laser aiming and ranging module is also used to collect the height difference between the fiber optic probe of the drone spectrometer and the target area to obtain the laser ranging; The controller is also used to use the ground image and the laser ranging as field of view information.

2. The sighting and field of view information acquisition device according to claim 1, characterized in that: The optical image acquisition module is also used to acquire a first ground image of the target area after the laser sighting and ranging module is turned on, and to acquire a second ground image of the target area after the laser sighting and ranging module is turned off.

3. A method for determining a spectral field of view, characterized in that: include: Acquire the field of view information when the drone collects non-imaging spectra, the field of view information is collected by the sighting and field of view information collection device of any one of claims 1 or 2, including the ground image of the target area and the laser ranging between the fiber optic probe of the drone spectrometer and the target area; The acquisition mode of the UAV spectrum is obtained, and the spectral field of view range is determined based on the acquisition mode and the field of view information.

4. The method for determining the spectral field of view range according to claim 3, characterized in that: The acquisition mode of obtaining the spectrum of the drone includes: Determine the acquisition mode of the spectrum of the drone based on the verticality of the gimbal; If it is determined that the acquisition mode is the vertical acquisition mode, the laser distance measurement is used as the vertical distance; If it is determined that the acquisition mode is the oblique acquisition mode, the laser ranging is used as the oblique distance.

5. The method for determining the spectral field range according to claim 3, characterized in that: The determining of the spectral field of view range based on the acquisition mode and the field of view information includes: Determine the radius of the field of view circle according to the optical fiber field angle of the spectrometer and the laser ranging; Determine the center point of the ground image; Determining the image spatial resolution based on the laser ranging; The spectral field of view range is determined according to the field of view circle radius, the center point and the image space resolution.

6. The method for determining the spectral field range according to claim 5, characterized in that: Determining the spectral field of view range according to the field of view circle radius, the center point and the image spatial resolution includes: Generate a mask according to the field of view circle radius, the center point and the image space resolution; A spectral field of view range is generated according to the mask.

7. A device for determining a spectrum field range, characterized in that: include: A field of view information acquisition module, used to acquire field of view information when the drone collects non-imaging spectra, wherein the field of view information is acquired by the sighting and field of view information acquisition device of any one of claims 1 or 2, including a ground image of a target area and a laser ranging between the drone and the target area; The field of view range determination module is used to obtain the acquisition mode of the drone and determine the spectral field of view range based on the acquisition mode and the field of view information.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for determining the spectral field range according to any one of claims 3 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for determining the spectral field range according to any one of claims 3 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for determining the spectral field range according to any one of claims 3 to 6 is implemented.

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