A real-time processing system and method for aircraft-to-ground laser illumination accuracy

Abstract

This invention relates to a real-time processing system and method for the accuracy of laser illumination of ground targets by aircraft, belonging to the field of civil test aircraft and helicopter avionics technology. It includes a spot monitor and a laser illumination accuracy processing system at a ground flight monitoring center, suitable for scenarios where test aircraft illuminate ground targets with lasers. The spot monitor records the laser illumination spot data of the test aircraft illuminating the ground target in real time and transmits the data to the laser illumination accuracy processing system at the flight monitoring center. This system preprocesses the spot data, locates the spot center, calculates the deviation between the spot center and the target center, and then calculates the laser illumination accuracy based on the distance between the test aircraft and the target.

Description

Technical Field

[0001] This invention relates to a real-time processing system and method for the accuracy of laser illumination of ground targets by aircraft, belonging to the field of civil test aircraft and helicopter avionics technology. Background Technology

[0002] Optoelectronic pods have become the most common payloads for civilian drones and helicopters, possessing functions such as detection, identification, positioning, and ranging. Flight tests require experimental verification of these platforms. The accuracy of laser illumination on the experimental pod is one of the key factors in deciding whether to execute important tasks. Traditional flight tests involve post-flight processing, using the illumination accuracy to determine whether to proceed with subsequent important tasks—a method that is inefficient. The reasons for this inefficiency are twofold: firstly, it requires one test flight to assess illumination accuracy, and a decision on whether to execute an important task can only be made on the second flight; secondly, current flight tests largely rely on manual operation of video interpretation software to find the center of the light spot image frame by frame. A single illumination session can last from several seconds to tens of seconds, with 20-30 illuminations per second, requiring the processing of hundreds of video images per session. This manual processing is time-consuming, especially when multiple illuminations are performed within a single test flight, severely impacting data processing efficiency and hindering the planning of subsequent test procedures. Summary of the Invention

[0003] The purpose of this invention is to provide a real-time processing system and method for the accuracy of laser illumination on the ground from an aircraft. This method can complete the processing of the accuracy of each laser illumination during flight of the test aircraft, which can serve as the basis for whether to execute subsequent tasks and can scientifically and fairly evaluate the performance of the optoelectronic pod and the laser illuminator.

[0004] The technical solution of the present invention:

[0005] To achieve the above-mentioned objectives, according to a first aspect of the present invention, a real-time processing system for the accuracy of aircraft-to-ground laser irradiation is proposed, which is suitable for scenarios where a test aircraft irradiates a ground target with laser. The system is characterized by including a spot monitor and a ground flight monitoring center.

[0006] The light spot monitor is positioned diagonally in front of the ground target;

[0007] The ground flight monitoring center is equipped with a laser irradiation accuracy processing system and a test aircraft status monitoring system.

[0008] The spot monitor is communicatively connected to the ground monitoring center; the laser irradiation accuracy processing system is communicatively connected to the testing machine status monitoring system.

[0009] The spot monitor is used to record the laser spot data of the test aircraft illuminating the ground target, and transmit the data to the laser illumination accuracy processing system of the flight monitoring center.

[0010] The testing machine status monitoring system is communicatively connected to the testing machine; it receives flight status data transmitted by the testing machine and transmits the position and time data from the flight data to the laser irradiation accuracy processing system.

[0011] The laser irradiation accuracy processing system utilizes the received laser irradiation spot data and the position and time data in the flight data to achieve real-time image preprocessing, spot irradiation center point positioning, irradiation accuracy calculation and evaluation.

[0012] In one possible embodiment, the spot monitor is positioned 1.5-2 km diagonally in front of the ground target, at an angle of 30°-45° to the front of the ground target.

[0013] According to a second aspect of the present invention, a real-time processing method for the accuracy of aircraft-to-ground laser illumination is proposed. The method employs the aforementioned real-time processing system for aircraft-to-ground laser illumination accuracy. The overall scheme involves a spot monitor recording a video of the laser illumination spot of the test aircraft and transmitting it to the flight monitoring center via a data link. The spot illumination accuracy processing system at the flight monitoring center calculates the spot illumination accuracy based on the test aircraft's position data and the spot video, and compares and analyzes it with indicators as one of the bases for deciding whether to execute subsequent important tasks.

[0014] Specifically, a real-time processing method for the accuracy of aircraft-to-ground laser illumination is applicable to scenarios where test aircraft illuminate ground targets with lasers, including a spot monitor and a ground flight monitoring center before flight testing;

[0015] Before the test aircraft takes off, obtain the coordinates and dimensions of the ground target;

[0016] Before the test aircraft takes off, adjust the time of the spot monitor to match the time of the test aircraft; place the spot monitor diagonally in front of the ground target.

[0017] During flight, the experimental aircraft will conduct a laser irradiation of the ground target once according to the requirements of the experimental mission.

[0018] The spot monitor records the spot video and transmits the laser irradiation spot video to the laser irradiation accuracy processing system in the flight monitoring center after one irradiation is completed; at the same time, the test aircraft transmits position data and time data to the test aircraft status monitoring system in the flight monitoring center.

[0019] The laser irradiation precision processing system performs spot center processing on the laser irradiation spot video and calculates the pixel coordinates of the irradiation center of each spot on the laser irradiation spot video.

[0020] The laser irradiation precision processing system calculates the coordinate distance represented by each pixel based on the size of the ground target.

[0021] The laser irradiation accuracy processing system calculates the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target based on the calculated pixel coordinates of the irradiation center of each spot and the calculated coordinate distance.

[0022] The laser irradiation accuracy processing system calculates the real-time distance between the testing machine and the ground target based on the testing machine's position data, time data, and ground target coordinates received by the testing machine's status monitoring system.

[0023] The real-time laser irradiation accuracy is calculated based on the distance deviation between the pixel coordinates of the irradiation center of each light spot and the center of the ground target, as well as the real-time distance between the test machine and the ground target.

[0024] Advantages of this invention:

[0025] This invention can transform post-flight processing into near real-time processing during flight, providing results quickly after each irradiation, instead of the traditional method of providing results after flight, thus improving processing and decision-making efficiency.

[0026] The processing is highly automated, reducing the time required for the same data processing from 30 minutes to less than 1 minute.

[0027] This method can be applied to the test flights and quality inspection of photoelectric sensors for various types of civilian UAVs and helicopters in my country. It has wide applicability and broad market prospects. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the system composition according to a preferred embodiment of the present invention.

[0029] Figure 2 Typical laser irradiation spot Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings.

[0031] A system and method for real-time processing of the accuracy of aircraft-to-ground laser illumination, the system layout of which is shown in the figure below. Figure 1 As shown, a typical processed light spot is as follows: Figure 2 As shown.

[0032] Step 1: Obtain the coordinates and dimensions of the ground target. Measure the coordinates of the ground target using a GPS measuring device with the same positioning accuracy as the test aircraft's navigation system. Measure the horizontal and vertical dimensions of the target using a ruler with a measurement accuracy of 0.01 meters. Inform the flight monitoring center personnel of the measurement results and input them into the laser illumination accuracy processing system for subsequent illumination accuracy processing.

[0033] Step 2: Before the test aircraft takes off, the spot monitor and the test aircraft use the same time scale system. The time of the spot monitor and the time of the test aircraft are adjusted to be consistent to ensure that they are in the same time coordinate, so as to facilitate subsequent data processing.

[0034] Step 3: Deploy the spot monitor 1.5-2km diagonally in front of the ground target, with an angle of 30°-45° between it and the front of the ground target.

[0035] Step 4: The test aircraft takes off and, in the air, performs a laser irradiation on the ground target according to the test mission requirements.

[0036] Step 5: The spot monitor records the spot video and transmits the laser irradiation spot video to the laser irradiation accuracy processing system of the flight monitoring center after one irradiation is completed; at the same time, the test machine transmits the position data and time data to the test machine status monitoring system of the flight monitoring center.

[0037] Step 6: The laser illumination accuracy processing system performs spot center processing on the laser illumination spot video. This involves two steps: first, preprocessing; then, spot center localization, which calculates the pixel coordinates of the center of the spot in each frame of the laser illumination spot video. The preprocessing algorithm can be one or more of gamma transformation, piecewise linear transformation, or local contrast enhancement algorithms. The spot center localization algorithm can use the gray-scale centroid method, ellipse fitting method, or Gaussian fitting method to locate the pixel coordinates of the center of the spot in each frame.

[0038] The mathematical expression for piecewise linear enhancement is as follows:

[0039]

[0040] If |c'-a'| < |ca|, then the first interval [a,c] is compressed, |d'-c'| = |dc|, the second interval [c,d] is maintained, and |b'-d'| > |bd|, the third interval [d,b] is expanded. By selecting appropriate segmentation points based on the image characteristics, small target enhancement can be achieved while suppressing background clutter.

[0041] Gamma transform has advantages such as improving the visual effect of images, correcting image illumination, and being computationally simple, and is widely used for enhancing low-quality images. Through nonlinear transformation, the gray values ​​of darker areas in an image can be enhanced, while the gray values ​​of brighter areas can be reduced. The principle is as follows:

[0042] s = cr γ (2)

[0043] Where r is the input value of the grayscale image, s is the grayscale output value after gamma transformation, c is the grayscale scaling factor, usually set to 1; γ is the gamma factor, which controls the scaling degree of the transformation.

[0044] Local contrast enhancement algorithms improve image clarity and visual appeal by readjusting the brightness distribution of the original image. The process involves first dividing the image into a series of sub-blocks, then performing histogram equalization on each sub-block individually, and finally merging the results to obtain the final image.

[0045] The steps of the grayscale centroid method are as follows: 1) After grayscale conversion and color inversion, threshold selection is performed to obtain the light spot feature region; 2) Blur and denoise, eliminating noise and noise caused by pixel inhomogeneity; 3) Threshold selection is performed again to obtain a clearer light spot region; 4) Morphological processing, selecting a suitable template, and performing erosion and filling processing on the image to obtain a regular shape of the connected region; 5) Edge detection is performed to obtain the image edge using detection operators such as Canny; 6) Morphological correlation operations are performed on the edge detection results to obtain a more connected edge curve, and the centroid is calculated through the edge curve function.

[0046] Ellipse fitting is a method that uses the least squares approach to fit an ellipse to the edges based on edge detection results, finding the center of the ellipse to replace the centroid of the light spot in the image. The general formula for an ellipse is as follows:

[0047] ax 2 +bxy+cy 2 +dx+ey+f=0 (3)

[0048] By using the principle of minimizing the difference, the optimal solutions for parameters a, b, c, d, e, and f are found, yielding the general equation of the ellipse. Using the optimal solution, the coordinates of the centroid are calculated. The expression for the centroid is as follows:

[0049]

[0050]

[0051] The Gaussian fitting method assumes that the intensity distribution of the laser spot in one-dimensional space (x) follows a Gaussian distribution. For most laser beams that need to be analyzed, the ideal intensity distribution should satisfy a Gaussian distribution, that is, the intensity distribution on any cross-section (x, y) perpendicular to the beam should be Gaussian. The Gaussian function is taken as:

[0052]

[0053] In the formula: I(x,y) is the light intensity of the laser beam at the cross section (x,y); H is the light intensity amplitude of the spot at the cross section; (x0,y0) is the center position of the spot; σ1 and σ2 are the standard deviations in two directions. It can be seen from the above formula that the position of the light intensity amplitude is the center position of the spot. Therefore, in this paper, the position where the light intensity amplitude is located is used as the center position of the spot. Taking the logarithm of both sides of the above formula and simplifying it to a polynomial, we get:

[0054] z = ax 2 +by 2 +cx+dy+f (6)

[0055] According to the least squares principle (minimum sum of squared residuals), a, b, c, d, and f can be determined by the following formula:

[0056]

[0057] Since image acquisition devices typically have an effective bit depth of 8 bits, high light intensity or long exposure times can easily lead to data saturation (grayscale values ​​exceeding 255), failing to reflect the true light intensity of the spot. Using these saturated points for Gaussian fitting can introduce significant errors; therefore, these saturated points must be removed. The value range of E should be I. th <I(x′ i ,y′ i )<255, where I th The threshold for separating the light spot from the background in the image is given by substituting all points in the image that meet this condition into the above formula to obtain the parameters a, b, c, d, and f. Then, the center position (x0, y0) of the light spot and the light intensity amplitude H can be obtained according to the following formula:

[0058]

[0059] For most beams that need to be analyzed, the ideal beam intensity distribution follows a Gaussian distribution.

[0060] Step 7: Calculate the coordinate distance represented by each pixel. The flight monitoring center manually marks the pixel coordinates of the four corners and the center marker of the target in the spot video, starting from the upper left corner of the target (x...). l1 ,y l1 ( and bottom right corner) (x) r2 ,y r2 The pixel coordinates of the target plate can be used to calculate the pixel width w and height h:

[0061]

[0062] Based on the actual height H and width W of the target plate, the ratio ε between the actual horizontal and vertical distances and the pixel distances can be calculated. x ε yThey are respectively:

[0063]

[0064] Step 8: The laser irradiation accuracy processing system calculates the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target based on the pixel coordinates of the irradiation center obtained in Step 6 and the coordinate distance obtained in Step 7. Specifically, it calculates the actual horizontal distance x between the center of each spot and the center of the target plate for each frame. n The actual vertical distance y is respectively n for:

[0065]

[0066] Among them, (x n (x, y) represents the center pixel coordinates of the light spot in the nth frame, and (x, y) represents the center pixel coordinates of the target plate.

[0067] Therefore, the actual distance difference between the center of the light spot and the center of the target plate in each frame is:

[0068]

[0069] Step 9: The laser irradiation accuracy processing system calculates the real-time distance L between the testing machine and the ground target based on the testing machine's position data, time data, and ground target coordinates received from the testing machine status monitoring system. n .

[0070] Step 10 calculates the real-time laser irradiation accuracy based on the distance deviation between the pixel coordinates of the irradiation center of each light spot calculated in Step 8 and the center of the ground target, and the real-time distance between the test machine and the ground target calculated in Step 9, thus obtaining the irradiation accuracy at each moment:

[0071]

[0072] Finally, the beam irradiation accuracy was calculated using the root mean square error formula as follows:

[0073]

[0074] Where N is the total number of frames of the spot image during one laser irradiation process, and the irradiation accuracy is in mrad.

[0075] Example

[0076] Taking the number of test flights of an electro-optical pod based on a type of civil experimental aircraft in 2021 as an example, the above steps are illustrated below:

[0077] Step 1: Obtain the coordinates and dimensions of the ground target. Measure the coordinates of the ground target using a GPS measuring device with the same positioning accuracy as the UAV's navigation system. Use a ruler with a measurement accuracy of 0.01 meters to measure the horizontal and vertical dimensions of the target. The target dimensions are found to be 6m wide and 5m high. The measurement results are then communicated to the flight monitoring center personnel for entry into the laser illumination accuracy processing system for subsequent illumination accuracy processing.

[0078] Step 2: Before the test aircraft takes off, place the spot monitor and the test aircraft together on the runway. Use the test aircraft's time synchronization system to synchronize the time of the spot monitor with the time of the test aircraft, ensuring that the two are within the same time coordinate, so as to facilitate subsequent data processing.

[0079] Step 3: Deploy the spot monitor 2km diagonally in front of the ground target, with an angle of 30° between it and the front of the ground target. The spot monitor is 20km away from the flight monitoring center. The spot monitor, the test aircraft and the flight monitoring center all transmit data through the C-band data link.

[0080] Step 4: The test aircraft takes off and performs its mission. At an altitude of 3 km and a slant distance of 7 km from the target, it begins to emit laser light to illuminate the target. Each illumination lasts for 5 seconds, with 20 illuminations per second. The test aircraft transmits its position and time data to the test aircraft status monitoring system at the flight monitoring center in real time.

[0081] Step 5: After the spot monitor detects a spot, it triggers recording and records the spot video. Recording stops after three consecutive cycles when no spot is detected. The operator selects the recorded spot video and sends it to the laser irradiation accuracy processing system in the flight monitoring center via a wireless link.

[0082] Step 6: The laser illumination accuracy processing system performs spot center processing on the laser illumination spot video. This involves two steps: first, preprocessing; then, spot center localization, which calculates the pixel coordinates of the center of the spot in each frame of the laser illumination spot video. The preprocessing algorithm uses a piecewise linear transformation, and the spot center localization algorithm uses ellipse fitting to locate the pixel coordinates of the center of the spot in each frame.

[0083] The mathematical expression for piecewise linear enhancement is as follows:

[0084]

[0085] If |c'-a'| < |ca|, then the first interval [a,c] is compressed, |d'-c'| = |dc|, the second interval [c,d] is maintained, and |b'-d'| > |bd|, the third interval [d,b] is expanded. By selecting appropriate segmentation points based on the image characteristics, small target enhancement can be achieved while suppressing background clutter.

[0086] Ellipse fitting is a method that uses the least squares approach to fit an ellipse to the edges based on edge detection results, finding the center of the ellipse to replace the centroid of the light spot in the image. The general formula for an ellipse is as follows:

[0087] ax 2 +bxy+cy 2 +dx+ey+f=0 (16)

[0088] By using the principle of minimizing the difference, the optimal solutions for parameters a, b, c, d, e, and f are found, yielding the general equation of the ellipse. Using the optimal solution, the coordinates of the centroid are calculated. The expression for the centroid is as follows:

[0089]

[0090]

[0091] Step 7: Calculate the coordinate distance represented by each pixel. The flight monitoring center manually marks the pixel coordinates of the four corners and the center marker of the target in the spot video. The pixel height h and width w of the target can be calculated from the pixel coordinates (550, 1300) and (1100, 210) of the upper left and lower right corners of the target.

[0092]

[0093] Based on the actual length H and width W of the target plate, the ratio ε between the actual horizontal and vertical distances and the pixel distances can be calculated. x ε y They are respectively:

[0094]

[0095] Step 8: The laser irradiation accuracy processing system calculates the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target based on the pixel coordinates of the irradiation center obtained in Step 6 and the coordinate distance obtained in Step 7. Specifically, it calculates the actual horizontal distance x between the center of each spot and the center of the target plate for each frame. n The actual vertical distance y is respectively n for:

[0096]

[0097] Among them, (x n ,y n (x,y) represents the center pixel coordinates of the light spot in the nth frame, and (x,y) represents the center pixel coordinates of the target board, which are (825,755) in this case.

[0098] Therefore, the actual distance difference between the center of the light spot and the center of the target plate in each frame is:

[0099]

[0100] Step 9: The laser irradiation accuracy processing system calculates the real-time distance L between the testing machine and the ground target based on the testing machine's position data, time data, and ground target coordinates received from the testing machine status monitoring system. n .

[0101] Step 10: The distance deviation R between the pixel coordinates of the illumination center of each light spot and the center of the ground target, calculated in Step 8. n The real-time distance L between the testing machine and the ground target, calculated in step 9. n Dividing the two yields the illumination accuracy at each time step. The illumination accuracy at each time step is:

[0102]

[0103] Finally, the beam irradiation accuracy was calculated using the root mean square error formula as follows:

[0104]

[0105] Where N is the total number of frames of the spot image during a single laser irradiation process, which is 100 in this case, and the final calculated irradiation accuracy is 0.077 mrad.

Claims

1. A real-time processing system for the accuracy of aircraft-to-ground laser illumination, suitable for scenarios where a test aircraft illuminates a ground target with a laser, characterized in that... Including spot monitors and ground flight monitoring centers; The light spot monitor is positioned diagonally in front of the ground target; The ground flight monitoring center is equipped with a laser irradiation accuracy processing system and a test aircraft status monitoring system. The spot monitor is connected to the ground monitoring center; the laser irradiation accuracy processing system is connected to the testing machine status monitoring system. The spot monitor is used to record the laser spot data of the test aircraft illuminating the ground target, and transmit the data to the laser illumination accuracy processing system of the flight monitoring center. The testing machine status monitoring system is communicatively connected to the testing machine; it receives flight status data transmitted by the testing machine and transmits the position and time data from the flight data to the laser irradiation accuracy processing system. The laser irradiation accuracy processing system utilizes the received laser irradiation spot data and the position and time data in the flight data to achieve real-time image preprocessing, spot irradiation center point positioning, irradiation accuracy calculation and evaluation. The laser irradiation accuracy processing system processes the laser irradiation spot video to calculate the pixel coordinates of the irradiation center of each spot in the video; it calculates the coordinate distance represented by each pixel based on the size of the ground target; it calculates the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target based on the pixel coordinates and coordinate distances of each spot; it calculates the real-time distance between the testing machine and the ground target based on the testing machine's position data, time data, and ground target coordinates received by the testing machine status monitoring system; and it calculates the real-time laser irradiation accuracy based on the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target, as well as the real-time distance between the testing machine and the ground target.

2. The real-time processing system for aircraft-to-ground laser illumination accuracy according to claim 1, characterized in that, The spot monitor is positioned 1.5-2 km diagonally in front of the ground target, with an angle of 30°-45° between it and the front of the ground target.

3. A method for real-time processing of aircraft-to-ground laser illumination accuracy, employing the real-time processing system for aircraft-to-ground laser illumination accuracy as described in any one of claims 1-2, characterized in that, Includes the following steps: Step 1: Obtain the coordinates and dimensions of the ground target; Step 2: Before the test machine takes off, adjust the time of the light spot monitor to match the time of the test machine; Step 3: Deploy the light spot monitor diagonally in front of the ground target; Step 4: The test aircraft takes off and performs a laser irradiation on the ground target according to the test mission requirements; Step 5: The spot monitor records the spot video and transmits the laser irradiation spot video to the laser irradiation accuracy processing system of the flight monitoring center after one irradiation is completed; at the same time, the test machine transmits the position data and time data to the test machine status monitoring system of the flight monitoring center. Step 6: The laser irradiation precision processing system performs spot center processing on the laser irradiation spot video and calculates the pixel coordinates of the irradiation center of each spot on the laser irradiation spot video. Step 7: The laser irradiation precision processing system calculates the coordinate distance represented by each pixel based on the size of the ground target; Step 8: The laser irradiation accuracy processing system calculates the distance deviation between the pixel coordinates of the irradiation center of each spot and the center of the ground target based on the pixel coordinates of the irradiation center of each spot calculated in Step 6 and the coordinate distance calculated in Step 7. Step 9: The laser irradiation accuracy processing system calculates the real-time distance between the testing machine and the ground target based on the testing machine position data, time data, and ground target coordinates received by the testing machine status monitoring system. Step 10: Calculate the real-time laser irradiation accuracy based on the distance deviation between the pixel coordinates of the irradiation center of each spot calculated in Step 8 and the center of the ground target, and the real-time distance between the test machine and the ground target calculated in Step 9.

4. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, In step 2, before the test machine takes off, a unified time synchronization system is used to synchronize the time of the spot monitor and the test machine to align the time markers.

5. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, In step 1, before the test aircraft takes off, the coordinates of the ground target are measured using a GPS measuring device with the same positioning accuracy as the test aircraft's navigation system.

6. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, In step 6, the laser-irradiated spot image video is first preprocessed to improve contrast. The specific preprocessing algorithm is one or more of gamma transformation, piecewise linear transformation, or local contrast enhancement algorithm. Then, the center of the spot is located. The specific method can be to use the gray-scale centroid method, ellipse fitting method, or Gaussian fitting method to locate the pixel coordinates of the center of the spot in each frame.

7. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, Step 7 specifically includes the following steps: In the light spot video, the pixel coordinates of the four corners and the center marker of the target are determined, starting from the upper left corner of the target plate. and bottom right corner The pixel coordinates can be used to calculate the pixel width of the target plate. and high : (1) Based on the actual height of the input target plate Hekuan It can calculate the ratio between the actual horizontal and vertical distances and the pixel distances. , They are respectively: (2)。 8. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, Step 8 specifically includes the following steps: Calculate the actual horizontal distance between the center of the light spot and the center of the target plate in each frame. and actual vertical distance respectively for: (3) in, For the first The center pixel coordinates of the frame spot The center pixel coordinates of the target plate. Therefore, the actual distance difference between the center of the light spot and the center of the target plate in each frame is: (4)。 9. The method for real-time processing of the accuracy of aircraft-to-ground laser illumination according to claim 3, characterized in that, Step 10 specifically includes the following steps: After obtaining the physical deviation of the center of the light spot in each frame, it is compared with the distance between the test machine and the target. By performing a division, the irradiation accuracy at each time point is obtained. The irradiation accuracy at each time point is: (5) Finally, the beam irradiation accuracy was calculated using the root mean square error formula as follows: (6) Wherein, is the total number of frames of the spot image during one laser irradiation process, and the irradiation accuracy is in mrad.

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