An aerial array camera view axis calibration device and method

Abstract

The application provides an aerial array camera visual axis calibration device, and particularly relates to the technical field of aerial calibration, which comprises an aerial array camera, a test support and a collimator, wherein the aerial array camera comprises a primary mirror, a secondary mirror, a back mirror, a first installation base surface, a positioning pin, a servo outer frame, a servo inner frame and a detector; the first installation base surface of the aerial array camera and the back mirror of the aerial array camera are related through a first plane mirror and a theodolite; the back mirror of the aerial array camera and the visual axis of the aerial array camera are related through the collimator and the theodolite; and the deviation angle is corrected through the servo inner frame and the servo outer frame, so that the visual axis calibration of the aerial array camera is completed. The optical equipment adjustment personnel do not need to consider the influence of the installation positions of the adjusting pads and the detector on the visual axis, and the calibration efficiency is higher.

Description

Technical Field

[0001] This invention relates to the field of aviation calibration technology, and in particular to an aerial area array camera line-of-sight calibration device and method. Background Technology

[0002] Long-range high-resolution aerial cameras are one of the important devices for achieving ground reconnaissance, target search, positioning and tracking, and detection. With the improvement of performance, aerial cameras not only need to acquire high-resolution, high-quality images, but also need to have the function of high-precision target positioning. The target positioning accuracy of aerial cameras is directly related to the line-of-sight pointing accuracy, onboard POS accuracy, onboard IMU accuracy, and encoder accuracy. Due to the long imaging distance, the angular accuracy of the line-of-sight pointing has the most significant impact on the target positioning accuracy.

[0003] When calculating the target position, the line-of-sight pointing angle is determined in the aircraft coordinate system. Due to factors such as mechanical installation and encoder zero-position error, there is a certain angular error between the actual line-of-sight pointing reference and the aircraft coordinate system. Therefore, in order to achieve high-precision positioning of long-range aerial cameras, the line-of-sight pointing reference of the aerial camera must be calibrated. This is done by calibrating the encoder zero position in both the pitch and azimuth directions to make the line-of-sight pointing reference consistent with the aircraft coordinate system.

[0004] Application number CN111083470A provides a line-of-sight calibration method. This invention involves installing a self-collimating through-center mirror on the lens base surface, adjusting the relative position of the detector and lens using a theodolite, determining the position of the lens and detector relative to the housing using the theodolite and a nearby target, and finally fixing the detector and lens by adjusting the installation pads. First, this patent heavily relies on the installation experience of optical technicians and requires repeated adjustments to the installation pads. Second, since this method is mainly aimed at transmissive short-focal-length optical systems, it is not suitable for aerial cameras with reflective long-focal-length optical systems that require long-range imaging. Furthermore, long-focal-length optical systems cannot produce clear images of nearby targets. Therefore, this patent is not applicable to aerial cameras with reflective long-focal-length optical systems that require long-range imaging. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a line-of-sight calibration device and method for an airborne area array camera.

[0006] This invention is achieved through the following technical solution:

[0007] This invention proposes a line-of-sight calibration device for an airborne area array camera.

[0008] Includes an aerial area array camera, a test stand, a theodolite, and a collimator, among which:

[0009] The airborne area array camera includes a primary mirror, a secondary mirror, a rear mirror, a first mounting base, positioning pins, a servo outer frame, a servo inner frame, and a detector.

[0010] The rear mirror is fixed to one side of the secondary mirror, the servo inner frame is fixed to the inner side of the servo outer frame, the secondary mirror is located on one side of the servo inner frame, and the imaging detector is fixed to the other side of the servo inner frame.

[0011] The test bracket includes a second mounting base surface located on both sides, and positioning pin holes are provided on the second mounting base surface. A first plane mirror is provided on the top edge of the other side of the test bracket. The first plane mirror is parallel to the second mounting base surface and is fixedly connected to the test bracket.

[0012] The collimator is used to reflect parallel light, and the theodolite is placed between the collimator and the first plane mirror.

[0013] Furthermore, it also includes a two-dimensional adjustment frame, wherein the airborne area array camera is fixed to the side of the test bracket near the second mounting base, the two-dimensional adjustment frame is located at the bottom of the test bracket, and the test bracket is fixedly connected to the two-dimensional adjustment frame.

[0014] Furthermore, the servo outer frame also includes a pitch encoder, and the servo inner frame also includes an azimuth encoder. The pitch encoder is used to monitor the rotation degree of the servo outer frame, and the azimuth encoder is used to monitor the rotation degree of the servo inner frame.

[0015] Furthermore, it also includes an encoder degree display device and a computer. The encoder degree display device is used to read the degrees of the pitch encoder and the azimuth encoder, and the computer is used to read the real-time output images of the aerial area array camera.

[0016] Furthermore, it also includes a light source and a target, the target being located at the focal plane of the collimator, the light source being used to provide light, and the light emitted from the light source passing sequentially through the target, the collimator, the theodolite, and the airborne area array camera.

[0017] Furthermore, a calibration method for an aerial area array camera line-of-sight calibration device is provided.

[0018] Includes the following steps:

[0019] S1. Install and adjust the aerial array camera;

[0020] S2. Establish the normal relationship between the first mounting base of the airborne area array camera and the back mirror of the airborne area array camera;

[0021] S3. Establish the relationship between the normal of the back mirror of the airborne area array camera and the line of sight of the airborne area array camera;

[0022] S4. Complete the line-of-sight calibration of the aerial area array camera.

[0023] Furthermore, the installation and adjustment of the aerial area array camera in step S1 includes the following steps:

[0024] The airborne area array camera was mounted on the test bracket, and the test bracket was placed on the two-dimensional adjustment frame;

[0025] Adjust the position of the two-dimensional adjustment frame so that the aperture of the collimator completely covers the optical aperture of the airborne area array camera and the first plane mirror;

[0026] The encoder degree display device is connected to the airborne area array camera via a cable.

[0027] Furthermore, establishing the normal relationship between the mounting base of the aerial area array camera and the back mirror of the aerial camera in step S2 includes the following steps:

[0028] Place the theodolite between the collimator and the first plane mirror, and place the visible light source at the target location.

[0029] Level the theodolite and align it with the collimator, ensuring that the visible light from the target falls on the crosshairs of the theodolite.

[0030] Record the pitch angle M1 and azimuth angle N1 of the theodolite;

[0031] Rotate the theodolite horizontally by 180 degrees, and adjust the pitch angle to 180-M1 degrees and the azimuth angle to -N1 degrees, while simultaneously aligning the theodolite with the first plane mirror;

[0032] Adjust the two-dimensional adjustment frame so that the autocollimation of the theodolite falls completely on the crosshairs of the theodolite;

[0033] Keeping the collimator and test bracket in the same position, place the theodolite between the back mirror and the collimator;

[0034] Level the theodolite and align it with the collimator, ensuring that the visible light from the target falls on the crosshairs of the theodolite.

[0035] Record the pitch angle M2 and azimuth angle N2 of the theodolite;

[0036] Rotate the theodolite horizontally by 180 degrees, and adjust the pitch angle to 180-M2 degrees and the azimuth angle to -N2 degrees, while simultaneously aligning the theodolite with the rear mirror;

[0037] Adjust the inner and outer servo frames so that the autocollimation of the theodolite falls completely on the crosshairs of the theodolite;

[0038] Read and record the pitch and azimuth encoder values ​​M3 and N3 of the aerial array camera;

[0039] M3 and N3 are used as the initial zero positions of the pitch encoder and azimuth encoder, respectively, while the servo outer frame and servo inner frame are controlled to move to the positions of M3 and N3.

[0040] Furthermore, establishing the relationship between the normal of the back mirror of the airborne area array camera and the line of sight of the airborne area array camera in step S3 includes the following steps:

[0041] Read real-time images from the airborne area array camera and record the target's pitch and azimuth image coordinates M4 and N4;

[0042] Calculate the pitch angle and azimuth angle between the line of sight and the normal to the back mirror, where:

[0043] Pitch direction: M5 = arctan((H / 2 - M4) * d / f) * 57.3;

[0044] Azimuth: N5 = arctan((L / 2 - N4) * d / f) * 57.3;

[0045] The size of the detector's imaging target surface is H*L, d is the detector pixel size, and f is the focal length of the airborne area array camera.

[0046] Update the zero-position angles of the pitch encoder and azimuth encoder, where:

[0047] Pitch encoder zero-position angle: M6 = (M3 + M5);

[0048] The zero-position angle of the azimuth encoder is: N6 = (N3 + N5).

[0049] The beneficial effects of this invention are:

[0050] (1) The aerial array camera line-of-sight calibration device proposed in this invention establishes the relationship between the first mounting base of the aerial array camera and the rear mirror of the aerial array camera through the first plane mirror and the theodolite, and then establishes the relationship between the secondary rear mirror of the aerial array camera and the line-of-sight of the aerial array camera through the collimator and the theodolite. The deviation angle is corrected by the servo inner frame and the servo outer frame, thereby completing the line-of-sight calibration of the aerial array camera. Optical assembly personnel do not need to consider the influence of the installation position of the adjustment pad and the detector on the line-of-sight, and the calibration efficiency is higher.

[0051] (2) When the line of sight of the airborne area array camera proposed in this invention changes due to long-term vibration and high and low temperatures, the assembly and adjustment personnel do not need to open the airborne area array camera housing to reinstall the detector, and the accuracy of the airborne area array camera will not be reduced.

[0052] (3) After the airborne area array camera leaves the factory, due to environmental factors such as long-term vibration and high and low temperatures, the line of sight of the airborne area array camera may be inconsistent with that at the time of leaving the factory, which will affect the positioning accuracy of the airborne area array camera. The present invention does not require opening the airborne area array camera shell, so it will not affect the airtightness of the airborne area array camera. At the same time, it does not require optical assembly personnel to reinstall the detector to avoid accidental damage to the airborne area array camera. Attached Figure Description

[0053] Figure 1 This is an overall view of the aerial area array camera line-of-sight calibration device of the present invention;

[0054] Figure 2 This is a structural diagram of an airborne area array camera for the airborne area array camera line-of-sight calibration device of the present invention;

[0055] Figure 3 This is a structural diagram of the test bracket for the aerial area array camera line-of-sight calibration device of the present invention;

[0056] Figure 4 The target imaging position of the aerial array camera line-of-sight calibration device of the present invention;

[0057] In the figure: 1. Airborne area array camera, 11. Primary mirror, 12. Secondary mirror, 13. Rear mirror, 14. First mounting base, 15. Positioning pin, 16. Servo outer frame, 17. Servo inner frame, 18. Detector, 2. Theodolite, 3. Light source, 4. Target, 5. Collimator, 6. Computer, 7. Test bracket, 71. First plane mirror, 72. Second mounting base, 73. Positioning pin hole, 8. Two-dimensional adjustment frame, 9. Encoder degree display device;

[0058] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0059] To more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0060] Please refer to Figures 1-4 This invention proposes a line-of-sight calibration device for an airborne area array camera 1, comprising an airborne area array camera 1, a test support 7, a theodolite 2, and a collimator 5, wherein:

[0061] The airborne area array camera 1 includes a primary mirror 11, a secondary mirror 12, a rear mirror 13, a first mounting base 14, a positioning pin 15, a servo outer frame 16, a servo inner frame 17, and a detector 18;

[0062] The rear mirror 13 is fixed to one side of the secondary mirror 12, the servo inner frame 17 is fixed to the inside of the servo outer frame 16, the secondary mirror 12 is located on one side of the servo inner frame 17, and the imaging detector 18 is fixed to the other side of the servo inner frame 17.

[0063] The test bracket 7 includes a second mounting base surface 72 located on both sides, and a positioning pin hole 73 is provided on the second mounting base surface 72. A first plane mirror 71 is provided on the top edge of the other side of the test bracket 7. The first plane mirror 71 is parallel to the second mounting base surface 72 and is fixedly connected to the test bracket 7.

[0064] The collimator 5 is used to reflect parallel light, and the theodolite 2 is placed between the collimator 5 and the first plane mirror 71.

[0065] In this embodiment: the first mounting base 14 and the second mounting base 72 are used to provide a positioning base for fixing the airborne area array camera 1 on the test bracket;

[0066] Test bracket 7 is used to provide a housing structure for the first plane mirror 71 and the airborne area array camera 1;

[0067] The locating pin hole 73 is used to provide a positioning reference for the locating pin;

[0068] The positioning pin 15 is used to provide a fixing structure for the airborne area array camera 1;

[0069] The collimator 5 is used to provide parallel light;

[0070] The first plane mirror 71 is used to reflect light;

[0071] Theodolite 2 is used to assist in line-of-sight calibration;

[0072] The two-dimensional adjustment bracket 8 is used to adjust the horizontal position of the reflector and the aerial array camera 1;

[0073] Specifically, the mounting base includes a first mounting base 14 and a second mounting base 72. When the airborne area array camera 1 is mounted on the test bracket 7, the first mounting base 14 on the airborne area array camera 1 is aligned with the second mounting base 72 on the test bracket 7 to coincide, and the positioning pin 15 is aligned with the positioning pin hole 73 for fixation. After the test bracket 7 and the airborne area array camera 1 are fixed, the first mounting base 14 and the second mounting base 72 can be understood as the same plane. The back mirror 13 is fixed on the back of the secondary mirror 12. The back mirror 13 is a plane mirror that can reflect light. Through the first plane mirror 71, After the theodolite 2 establishes the relationship between the first mounting base 14 of the airborne area array camera 1 and the back mirror 13 of the airborne area array camera 1, the theodolite 2 then establishes the relationship between the secondary back mirror 13 of the airborne area array camera 1 and the line of sight of the airborne area array camera 1 through the collimator 5. The deviation angle is corrected by the servo inner frame 17 and the servo outer frame 16, thereby completing the line of sight calibration of the airborne area array camera 1. The optical assembly personnel do not need to consider the influence of the installation position of the adjustment pad and the detector 18 on the line of sight. At the same time, the present invention can separate the coupling error in the pitch and azimuth directions, compensate for the installation error of the camera, and achieve higher calibration efficiency.

[0074] In one embodiment, the test bracket 7 is L-shaped and has two sides, a front and a back. The first plane mirror 71 is fixed at the top left of the back of the test bracket 7. The left and right edges of the front of the test bracket 7 are each provided with a second mounting reference surface 72. The second mounting reference surface 72 is parallel to the first plane mirror 71. The two second mounting reference surfaces 72 are provided with a plurality of positioning pin holes 73. The number of positioning pin holes 73 can be selected according to the actual situation.

[0075] In one embodiment, the collimator 5 is an off-axis reflective collimator 5, which is used to convert light into parallel light.

[0076] In a real-time mode, the two-dimensional adjustment frame 8 adjusts the horizontal position of the reflector and the airborne area array camera 1. Through the adjustment of the two-dimensional adjustment frame 8, the collimator 5 can completely cover the airborne area array camera 1.

[0077] Furthermore, the servo outer frame 16 also includes a pitch encoder and the servo inner frame 17 includes an azimuth encoder. The pitch encoder is used to monitor the rotation degree of the servo outer frame 16, and the azimuth encoder is used to monitor the rotation degree of the servo inner frame 17. It also includes an encoder degree display device 9 and a computer 6. The encoder degree display device is used to read the degree values ​​of the pitch encoder and the azimuth encoder, and the computer 6 is used to read the real-time output images of the aerial area array camera 1.

[0078] Specifically, the servo inner frame 17 and the servo outer frame 16 can be adjusted in the horizontal and vertical directions respectively. The pitch encoder and the azimuth encoder detect the angles adjusted by the servo outer frame 16 and the servo inner frame 17 respectively. The encoder degree display device 9 monitors the data of the servo inner frame 17 and the servo outer frame 16 and feeds it back to the computer 6. The computer 6 then combines with the aerial array camera 1 to output images in real time to complete real-time monitoring.

[0079] Furthermore, it also includes a light source 3 and a target 4. The target 4 is located at the focal plane of the collimator 5. The light source 3 is used to provide light. The light emitted by the light source 3 passes through the target 4, the collimator 5, the theodolite 2 and the airborne area array camera 1 in sequence.

[0080] In this embodiment:

[0081] The collimator 5 is used to provide parallel light;

[0082] Specifically, the light source 3 includes a blackbody light source and a visible light source. The target 4 is a star target 4. The light emitted from the light source 3 passes through the target 4, the collimator 5, the theodolite 2 and the airborne area array camera 1 in sequence to complete the light focusing and imaging. When the detector 18 uses an infrared detector, it is necessary to switch to a blackbody light source in the later stage. In other cases, a visible light source can be used.

[0083] Furthermore, a calibration method for a line-of-sight calibration device for an aerial area array camera 1 includes the following steps:

[0084] S1. Install and adjust the aerial array camera;

[0085] S2. Establish the normal relationship between the first mounting base surface 14 of the airborne area array camera 1 and the rear mirror 13 of the airborne area array camera;

[0086] S3. Establish the relationship between the normal of the back mirror 13 of the aerial area array camera 1 and the line of sight of the aerial area array camera 1;

[0087] S4. Complete the orientation calibration of the aerial array camera's line of sight. In a real-time example, the line of sight of the aerial array camera 1 is the axis that is imaged through the optical system at the center of the image and perpendicular to the target surface of the detector 18.

[0088] Specifically, the secondary mirror 12 points to the coordinate reference established by the collimator 5, the theodolite 2, the back mirror 13 and the airborne area array camera 1. The relationship between the first mounting base 14 of the airborne area array camera 1 and the line of sight can be completed through two reference calibrations, that is, the line of sight calibration of the airborne area array camera 1 is completed.

[0089] Furthermore, the installation and adjustment of the aerial area array camera 1 in step S1 includes the following steps:

[0090] The airborne area array camera 1 is mounted on the test bracket 7, and the test bracket 7 is placed on the two-dimensional adjustment frame 8;

[0091] Adjust the position of the two-dimensional adjustment frame 8 so that the light transmission aperture of the collimator 5 completely covers the optical aperture of the airborne area array camera 1 and the first plane mirror 71.

[0092] The encoder degree display device 9 is connected to the airborne area array camera 1 via a cable.

[0093] Specifically, the encoder degree display device 9 is connected to the airborne area array camera 1 via a cable to read the real-time readings of the pitch and azimuth encoders. The two-dimensional adjustment frame 8 adjusts the horizontal position of the test bracket 7 so that the light transmission aperture of the collimator 5 completely covers the optical aperture of the airborne area array camera 1 and the first plane mirror 71.

[0094] Furthermore, the establishment of the normal relationship between the first mounting base 14 of the airborne area array camera 1 and the back mirror 13 of the airborne area array camera in step S2 includes the following steps:

[0095] Place the theodolite 2 between the collimator 5 and the first plane mirror 71, and place the visible light source 3 at the target 4.

[0096] Level the theodolite 2 and align it with the collimator 5, so that the visible light from the target 4 falls on the crosshairs of the theodolite 2.

[0097] Record the elevation angle M1 and azimuth angle N1 of the theodolite 2;

[0098] The theodolite 2 is rotated horizontally by 180 degrees, and the pitch angle is adjusted to 180-M1 degrees and the azimuth angle to -N1 degrees. At the same time, the theodolite 2 is aligned with the first plane mirror 71.

[0099] Adjust the two-dimensional adjustment frame 8 so that the autocollimation of the theodolite 2 falls completely on the crosshairs of the theodolite 2;

[0100] Keeping the positions of the collimator 5 and the test bracket 7 unchanged, place the theodolite 2 between the back mirror 13 and the collimator 5;

[0101] Level the theodolite 2 and align it with the collimator 5, so that the visible light from the target 4 falls on the crosshairs of the theodolite 2.

[0102] Record the elevation angle M2 and azimuth angle N2 of the theodolite 2;

[0103] Rotate the theodolite 2 horizontally by 180 degrees and adjust the pitch angle to 180-M2 degrees and the azimuth angle to -N2 degrees, while simultaneously aligning the theodolite 2 with the back mirror 13.

[0104] Adjust the servo inner frame 17 and servo outer frame 16 so that the autocollimating light source of the theodolite 2 falls completely on the crosshairs of the theodolite 2;

[0105] Read and record the pitch and azimuth encoder values ​​M3 and N3 of the aerial area array camera 1;

[0106] M3 and N3 are used as the initial zero positions of the pitch encoder and azimuth encoder, respectively, while the servo outer frame 16 and servo inner frame 17 are controlled to move to the positions of M3 and N3.

[0107] Specifically, M3 and N3 are used as the initial zero positions of the pitch encoder and azimuth encoder, respectively. At the same time, the servo outer frame 16 and servo inner frame 17 are controlled to move to the positions of M3 and N3. It can be understood that M3 and N3 are two degrees. M3 and N3 are set as the initial zero positions in the program. After power-on, the program recognizes M3 and N3 as 0 degrees. That is, the program controls the servo outer frame 16 and servo inner frame 17 to return to the zero position by moving to the two positions of M3 and N3.

[0108] Furthermore, the S3 step of establishing the relationship between the normal of the back mirror 13 of the airborne area array camera 1 and the line of sight of the airborne area array camera 1 includes the following steps:

[0109] Read the real-time images from the aerial array camera 1 and record the pitch and azimuth image coordinates M4 and N4 of the target 4;

[0110] Calculate the pitch angle and azimuth angle between the visual axis and the normal of the rear mirror 13, where:

[0111] Pitch direction: M5 = arctan((H / 2 - M4) * d / f) * 57.3;

[0112] Azimuth: N5 = arctan((L / 2 - N4) * d / f) * 57.3;

[0113] The imaging target size of detector 3 is H*L, d is the pixel size of detector 3, and f is the focal length of airborne area array camera 1.

[0114] Update the zero-position angles of the pitch encoder and azimuth encoder, where:

[0115] Pitch encoder zero-position angle: M6 = (M3 + M5);

[0116] The zero-position angle of the azimuth encoder is: N6 = (N3 + N5). For details, please refer to [reference needed]. Figure 4After calibration through steps S2 and S3, the aerial camera's line-of-sight pointing reference was made consistent with the aerial camera's coordinates. Then, the aerial array camera 1 was powered on, and the test computer 6 read the real-time image. When the detector target size is 640*512, the target 4 image should be at the center position (320, 256) of the image.

[0117] In one embodiment, before performing step S3, if the autocollimating light source of the theodolite 2 does not fall on the crosshairs of the theodolite 2, it is necessary to keep the positions of the collimator 5 and the test bracket 7 unchanged again, place the theodolite 2 between the back mirror 13 and the collimator 5; level the theodolite 2 and align it with the collimator 5, so that the visible light of the target 4 falls on the crosshairs of the theodolite 2; record the pitch angle M2 and azimuth angle N2 of the theodolite 2; rotate the theodolite 2 horizontally by 180 degrees, and adjust the pitch angle to 180-M2 degrees and the azimuth angle to -N2 degrees, while aligning the theodolite 2 with the back mirror 13; adjust the servo inner frame 17 and the servo outer frame 16 so that the autocollimating light source of the theodolite 2 falls completely on the crosshairs of the theodolite 2.

[0118] In one embodiment, if the detector is infrared, the light source at the target needs to be switched to a blackbody light source before reading the real-time image of the airborne area array camera 1. That is, the real-time image of the airborne area array camera 1 is read after switching to the blackbody light source.

[0119] In summary, after establishing the relationship between the first mounting base 14 and the back mirror 13 of the airborne area array camera 1 using the first plane mirror 71 and the theodolite 2, the relationship between the secondary back mirror 13 and the line of sight of the airborne area array camera 1 is established using the collimator 5 and the theodolite 2. The deviation angle is corrected by the servo inner frame 17 and the servo outer frame 16, thereby completing the line of sight calibration of the airborne area array camera 1. Optical assembly personnel do not need to consider the influence of the installation position of the adjustment pad and the detector 18 on the line of sight. At the same time, the present invention can separate the coupling error in the pitch and azimuth directions, compensate for the installation error of the camera, and achieve higher calibration efficiency. Finally, after the airborne area array camera 1 leaves the factory, due to long-term vibration, high and low temperature and other environmental factors, the line of sight of the airborne area array camera 1 may be inconsistent with that at the factory, which will affect the positioning accuracy of the airborne area array camera 1. The present invention does not require opening the outer shell of the airborne area array camera 1, thus avoiding the impact on the airtightness of the airborne area array camera 1. At the same time, optical assembly personnel do not need to reinstall the detector 18 to avoid accidental damage to the airborne area array camera.

[0120] Of course, the present invention may have many other embodiments. Based on this embodiment, other embodiments obtained by those skilled in the art without any creative effort are all within the scope of protection of the present invention.

Claims

1. A line-of-sight calibration device for an airborne area array camera, characterized in that, Includes an aerial area array camera, a test stand, a theodolite, and a collimator, among which: The airborne area array camera includes a primary mirror, a secondary mirror, a rear mirror, a first mounting base, positioning pins, a servo outer frame, a servo inner frame, and a detector. The rear mirror is a plane mirror capable of reflection. The rear mirror is fixed to one side of the secondary mirror, the servo inner frame is fixed to the inner side of the servo outer frame, the secondary mirror is located on one side of the servo inner frame, and the imaging detector is fixed to the other side of the servo inner frame. The test bracket includes a second mounting base surface located on both sides, and positioning pin holes are provided on the second mounting base surface. A first plane mirror is provided on the top edge of the other side of the test bracket. The first plane mirror is parallel to the second mounting base surface and is fixedly connected to the test bracket. The collimator is used to reflect parallel light, and the theodolite is placed between the collimator and the first plane mirror.

2. The aerial area array camera line-of-sight calibration device according to claim 1, characterized in that, It also includes a two-dimensional adjustment frame, wherein the airborne area array camera is fixed to the side of the test bracket near the second mounting base, the two-dimensional adjustment frame is located at the bottom of the test bracket, and the test bracket is fixedly connected to the two-dimensional adjustment frame.

3. The line-of-sight calibration device for an airborne area array camera according to claim 1, characterized in that, The servo outer frame also includes a pitch encoder, and the servo inner frame also includes an azimuth encoder. The pitch encoder is used to monitor the rotation degree of the servo outer frame, and the azimuth encoder is used to monitor the rotation degree of the servo inner frame.

4. The aerial area array camera line-of-sight calibration device according to claim 3, characterized in that, It also includes an encoder degree display device and a computer. The encoder degree display device is used to read the degree values ​​of the pitch encoder and the azimuth encoder, and the computer is used to read the real-time output images of the aerial area array camera.

5. The line-of-sight calibration device for an airborne area array camera according to claim 1, characterized in that, It also includes a light source and a target, the target being located at the focal plane of the collimator, the light source being used to provide light, and the light emitted by the light source passing sequentially through the target, the collimator, the theodolite and the airborne area array camera.

6. A calibration method for the line-of-sight calibration device for an aerial area array camera according to claims 1-5, characterized in that, Includes the following steps: S1. Install and adjust the aerial array camera; S2. Establish the normal relationship between the first mounting base of the airborne area array camera and the back mirror of the airborne area array camera; S3. Establish the relationship between the normal of the back mirror of the airborne area array camera and the line of sight of the airborne area array camera; S4. Complete the line-of-sight calibration of the aerial area array camera.

7. The method for calibrating the line-of-sight of an airborne area array camera according to claim 6, characterized in that, The installation and adjustment of the airborne area array camera in step S1 includes the following steps: The airborne area array camera was mounted on the test bracket, and the test bracket was placed on the two-dimensional adjustment frame; Adjust the position of the two-dimensional adjustment frame so that the aperture of the collimator completely covers the optical aperture of the airborne area array camera and the first plane mirror; The encoder degree display device is connected to the airborne area array camera via a cable.

8. The method for calibrating the line-of-sight of an airborne area array camera according to claim 7, characterized in that, The step S2, establishing the normal relationship between the mounting base of the aerial area array camera and the rear mirror of the aerial camera, includes the following steps: Place the theodolite between the collimator and the first plane mirror, and place the visible light source at the target location. Level the theodolite and align it with the collimator, ensuring that the visible light from the target falls on the crosshairs of the theodolite. Record the pitch angle M1 and azimuth angle N1 of the theodolite; Rotate the theodolite horizontally by 180 degrees, and adjust the pitch angle to 180-M1 degrees and the azimuth angle to -N1 degrees, while simultaneously aligning the theodolite with the first plane mirror; Adjust the two-dimensional adjustment frame so that the autocollimation of the theodolite falls completely on the crosshairs of the theodolite; Keeping the collimator and test bracket in the same position, place the theodolite between the back mirror and the collimator; Level the theodolite and align it with the collimator, ensuring that the visible light from the target falls on the crosshairs of the theodolite. Record the pitch angle M2 and azimuth angle N2 of the theodolite; Rotate the theodolite horizontally by 180 degrees, and adjust the pitch angle to 180-M2 degrees and the azimuth angle to -N2 degrees, while simultaneously aligning the theodolite with the rear mirror; Adjust the inner and outer servo frames so that the autocollimation of the theodolite falls completely on the crosshairs of the theodolite; Read and record the pitch and azimuth encoder values ​​M3 and N3 of the aerial array camera; M3 and N3 are used as the initial zero positions of the pitch encoder and azimuth encoder, respectively, while the servo outer frame and servo inner frame are controlled to move to the positions of M3 and N3.

9. The method for calibrating the line-of-sight axis of an airborne area array camera according to claim 8, characterized in that, The S3 step of establishing the relationship between the back mirror normal of the airborne area array camera and the line of sight of the airborne area array camera includes the following steps: reading the real-time image of the airborne area array camera and recording the pitch and azimuth image coordinates M4 and N4 of the target. Calculate the pitch angle and azimuth angle between the line of sight and the normal to the back mirror, where: Pitch direction: M5 = arctan((H / 2 - M4) * d / f) * 57.3; Azimuth: N5 = arctan((L / 2 - N4) * d / f) * 57.3; The size of the detector's imaging target surface is H*L, d is the detector pixel size, and f is the focal length of the airborne area array camera. Update the zero-position angles of the pitch encoder and azimuth encoder, where: Pitch encoder zero-position angle: M6 = (M3 + M5); The zero-position angle of the azimuth encoder is: N6 = (N3 + N5).

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