A method for correcting IMU installation deviation angle based on geo-tracking mode of photoelectric pod
By calibrating the IMU installation deviation angle online, the positioning and tracking accuracy problems caused by line-of-sight installation errors in the optoelectronic pod were solved, enabling precise target positioning and geographic tracking of the optoelectronic pod in flight and improving the efficiency of flight missions.
Patent Information
- Application Number
- CN202411642730.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2044-11-18
AI Technical Summary
In electro-optical pods, the installation error between the IMU and the line of sight of the electro-optical pod causes the frame to be non-orthogonal, affecting the accuracy of target positioning and geographic tracking. Traditional calibration methods require multiple flights or fixed routes, which compresses the effective time for mission execution.
By acquiring the target's true geographical location, the aiming line thickness adjustment angle is calculated in real time and written into the geographic tracking function. Combined with the attitude information of the electro-optical pod, online calibration is performed, and the final installation deviation angle is stored to achieve accurate calibration.
By completing basic alignment of the line of sight before takeoff, and achieving precise positioning and geographic tracking of the target during flight, the efficiency of flight mission execution is improved, and the positioning and tracking effects of subsequent flights are guaranteed.
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Figure CN119540355B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of optoelectronic control technology, and in particular to a method for correcting IMU installation deviation angles based on optoelectronic pod geographic tracking mode. Background Technology
[0002] The electro-optical pod is a multispectral airborne electro-optical detection system integrating infrared, visible light, and laser technologies, serving as a primary electro-optical reconnaissance device for aircraft platforms. The key component for high-precision positioning and geographic tracking within the electro-optical pod is the positioning and orientation system (POS), composed of an inertial measurement unit (IMU) and a navigation calculation (PCS) board. An external GPS provides GNSS signals to the POS, which then outputs combined navigation information to the electro-optical pod controller, enabling the pod to locate the target and obtain its geographic location. Simultaneously, combining this with the target's geographic location information, the electro-optical pod controller calculates the required rotational deviation angle, driving the pod's aiming line to quickly point towards the target, completing the staring tracking.
[0003] During actual assembly, installation errors between the IMU and the electro-optical pod's line of sight can cause the frame to be non-orthogonal, affecting target positioning and geographic tracking accuracy. Therefore, to obtain higher accuracy in target positioning and geographic tracking, it is necessary to calibrate the installation errors between the IMU and the electro-optical pod's line of sight.
[0004] Traditional installation error calibration methods require multiple flights or fixed routes, which have specific requirements on time and route, compressing the effective execution time of the mission. This invention performs online calibration by continuously correcting the target geographic tracking results through image-based line-of-sight angle calculation. This not only makes the target positioning and geographic tracking of the electro-optical pod more accurate during the current flight, but also ensures the target positioning and geographic tracking effect of subsequent flights by storing the calibrated installation deviation angle, significantly improving the execution efficiency of flight missions.
[0005] Therefore, it is necessary to improve one or more of the problems existing in the above-mentioned related technical solutions.
[0006] It should be noted that this section is intended to provide background or context for the technical solutions of this disclosure as set forth in the claims. The description herein does not constitute an admission that it is prior art simply because it is included in this section. Summary of the Invention
[0007] The purpose of this disclosure is to provide a method for correcting the installation deviation angle of an IMU based on a geographic tracking mode of an optoelectronic pod, thereby overcoming, to at least some extent, one or more problems caused by the limitations and defects of related technologies.
[0008] According to an embodiment of this disclosure, a method for correcting IMU installation deviation angle based on a photoelectric pod geographic tracking mode is provided, the method comprising:
[0009] The target's true geographical location is obtained, enabling the photoelectric pod to perform geographic tracking on the target;
[0010] Adjust the photoelectric sensor to a wide field of view, perform coarse adjustment on the photoelectric pod, align the aiming line of the photoelectric pod with the target, and calculate in real time the coarse adjustment angle corresponding to the aiming line in the current field of view; wherein, the coarse adjustment angle includes azimuth coarse adjustment angle and pitch coarse adjustment angle;
[0011] The coarse adjustment angle is written into the geographic tracking function as the initial IMU installation deviation angle;
[0012] Adjust the photoelectric sensor to a small field of view, fine-tune the photoelectric pod, and press the aiming line of the photoelectric pod onto the target, and calculate in real time the fine adjustment angle corresponding to the aiming line in the current field of view; wherein, the fine adjustment angle includes azimuth fine adjustment angle and pitch fine adjustment angle;
[0013] The fine-tuning angle is written into the geographic tracking function as the final IMU installation deviation angle and saved to the storage chip.
[0014] Furthermore, the step of obtaining the target's true geographical location and enabling the optoelectronic pod to perform geographic tracking of the target includes:
[0015] The predetermined geographical location of the target is bound together to obtain the target's location coordinates;
[0016] The target's position coordinates are converted to an optoelectronic geographic coordinate system, and combined with the attitude information of the optoelectronic pod, the target spatial pointing angle of the optoelectronic pod's rotation is obtained; wherein, the target spatial pointing angle of the optoelectronic pod's rotation includes the pointing azimuth angle and the pointing pitch angle;
[0017] The photoelectric pod is directed toward the target based on the target spatial pointing angle of its rotation.
[0018] Further, the step of converting the target's position coordinates to an optoelectronic geographic coordinate system and combining it with the attitude information of the optoelectronic pod to obtain the target spatial pointing angle of the optoelectronic pod's rotation includes:
[0019] The coordinates of the optoelectronic pod and the target are transformed from geodetic coordinates to optoelectronic geographic coordinates; wherein,
[0020] The coordinates of the photoelectric pod in the geographic coordinate system are: The target's coordinates in the geographic coordinate system are: Then the positional difference between the target and the photoelectric pod is:
[0021]
[0022] The coordinates of the target in the photoelectric coordinate system are, i.e., ;in, This is the matrix for converting geographic coordinates to photoelectric coordinates.
[0023] Based on the target's coordinates in the photoelectric coordinate system, the target spatial pointing azimuth angle of the rotating photoelectric pod is obtained. and pitch angle .
[0024] Further, the steps of adjusting the photoelectric sensor to a large field of view, coarsely adjusting the photoelectric pod, aligning the aiming line of the photoelectric pod with the target, and calculating the coarse adjustment angle corresponding to the aiming line in the current field of view in real time include:
[0025] Adjust the photoelectric sensor to the large field of view, divide the image into groups of 10 pixels, and move the aiming line toward the target under the geographic tracking position until it presses against the target;
[0026] The coarse azimuth movement pixel, coarse pitch movement pixel, and photoelectric sensor parameters of the aiming line movement are obtained, and the coarse azimuth adjustment angle and the coarse pitch adjustment angle are calculated.
[0027] Furthermore, the expression for the coarse azimuth adjustment angle is:
[0028]
[0029] The expression for the pitch coarse adjustment angle is:
[0030]
[0031] in, To move the coarse azimuth of the aiming line by pixels, To adjust the coarse pitch of the aiming line, move the pixel. For horizontal dimensions, , The size of the photoelectric sensor, This is the focal length of the photoelectric sensor.
[0032] Further, the steps of adjusting the photoelectric sensor to a small field of view, fine-tuning the photoelectric pod, aligning the aiming line of the photoelectric pod with the target, and calculating in real time the fine-tuning angles of azimuth and pitch corresponding to the aiming line in the current field of view include:
[0033] Reduce the field of view of the photoelectric sensor, adjust the photoelectric sensor to the small field of view, and move the aiming line toward the target in the geographic tracking position until the aiming line coincides with the center of the target;
[0034] The fine-tuning azimuth movement pixels, fine-tuning pitch movement pixels, and photoelectric sensor parameters of the aiming line movement are obtained, and the fine-tuning azimuth adjustment angle and the fine-tuning pitch adjustment angle are calculated.
[0035] Furthermore, the expression for the fine adjustment angle of the azimuth is:
[0036]
[0037] The expression for the pitch coarse adjustment angle is:
[0038]
[0039] in, To fine-tune the azimuth of the aiming line, move the pixel. To fine-tune the elevation of the aiming line, move the pixel. For horizontal dimensions, , The size of the photoelectric sensor, This is the focal length of the photoelectric sensor.
[0040] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects:
[0041] In the embodiments of this disclosure, the IMU installation deviation angle correction method based on the above-described geo-tracking mode of the electro-optical pod involves the following steps: First, before takeoff, the ground checks that the zero-point pointing of the electro-optical pod's line of sight is basically consistent with the pointing of the aircraft nose. After the aircraft takes off and enters the flight path, the electro-optical pod performs geo-tracking based on the target position. The electro-optical pod calculates the rotation azimuth and rotation pitch angles in real time based on the relative positions of the aircraft and the target, achieving staring tracking of the target. The electro-optical pod sensor is adjusted to a suitable field of view where the target appears in the image. The image is divided into groups of 10 pixels. Under the geo-tracking position, the aiming line is moved towards the target until it is pressed against the target, completing the coarse calibration of the IMU installation deviation angle. The electro-optical pod sensor is adjusted to the minimum field of view to further correct the geo-tracking position. When the center of the aiming line is moved to coincide with the center of the target, the moved field of view angle is written as the IMU installation deviation angle into the electro-optical pod's storage chip, completing the precise calibration of the IMU installation deviation angle. On the other hand, online calibration by continuously correcting the target geographic tracking results through image conversion of the line-of-sight angle not only makes the target positioning and geographic tracking of the electro-optical pod more accurate during the calibration flights, but also ensures the target positioning and geographic tracking effect of subsequent flights by storing the calibrated installation deviation angle, thus greatly improving the execution efficiency of flight missions. Attached Figure Description
[0042] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.
[0043] Figure 1 This diagram illustrates the steps of an IMU installation deviation angle correction method based on a photoelectric pod geographic tracking mode in an exemplary embodiment of this disclosure.
[0044] Figure 2 This diagram illustrates a specific flowchart of the IMU installation deviation angle correction method based on the geolocation tracking mode of the optoelectronic pod in an exemplary embodiment of this disclosure.
[0045] Figure 3 This diagram illustrates the principle of controlling the optoelectronic pod using an IMU installation deviation angle correction method based on the optoelectronic pod geographic tracking mode in an exemplary embodiment of this disclosure. Detailed Implementation
[0046] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that this disclosure will be more comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0047] Furthermore, the accompanying drawings are merely illustrative diagrams of embodiments of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.
[0048] This example implementation provides a method for correcting IMU installation deviation angles based on a geo-optical pod's geographic tracking mode. (Reference) Figure 1 As shown, the IMU installation deviation angle correction method based on the photoelectric pod geographic tracking mode may include steps S101 to S105.
[0049] Step S101: Obtain the target's true geographical location, and enable the photoelectric pod to perform geographic tracking on the target;
[0050] Step S102: Adjust the photoelectric sensor to a large field of view, perform coarse adjustment on the photoelectric pod, press the aiming line of the photoelectric pod into the target, and calculate the coarse adjustment angle corresponding to the aiming line in the current field of view in real time;
[0051] Step S103: Write the coarse adjustment angle as the initial IMU installation deviation angle into the geographic tracking function; wherein, the coarse adjustment angle includes the azimuth coarse adjustment angle and the pitch coarse adjustment angle;
[0052] Step S104: Adjust the photoelectric sensor to a small field of view, fine-tune the photoelectric pod, press the aiming line of the photoelectric pod into the target, and calculate the fine adjustment angle corresponding to the aiming line in the current field of view in real time; wherein, the fine adjustment angle includes azimuth fine adjustment angle and pitch fine adjustment angle;
[0053] Step S105: Write the fine-tuning angle as the final IMU installation deviation angle into the geographic tracking function and save it to the storage chip.
[0054] The above-described method for correcting IMU installation deviation angles based on the geo-tracking mode of the electro-optical pod involves several steps. First, before takeoff, ground checks ensure the zero-point orientation of the electro-optical pod's line of sight is roughly consistent with the nose direction. After takeoff and entering the flight path, the electro-optical pod performs geo-tracking based on the pre-set target position. The pod calculates the rotation azimuth and pitch angles in real-time based on the relative positions of the aircraft and the target, achieving staring tracking of the target. The pod's sensor is adjusted to a suitable field of view where the target appears in the frame. The frame is divided into groups of 10 pixels, and the aiming line is moved towards the target at the geo-tracking position until it overlaps with the target, completing the coarse calibration of the IMU installation deviation angle. The pod's sensor is then adjusted to the minimum field of view to further correct the geo-tracking position. When the center of the aiming line is moved to coincide with the target center, the shifted field of view angle is written into the pod's storage chip as the IMU installation deviation angle, completing the precise calibration of the IMU installation deviation angle. On the other hand, online calibration by continuously correcting the target geographic tracking results through image conversion of the line-of-sight angle not only makes the target positioning and geographic tracking of the electro-optical pod more accurate during the calibration flights, but also ensures the target positioning and geographic tracking effect of subsequent flights by storing the calibrated installation deviation angle, thus greatly improving the execution efficiency of flight missions.
[0055] Below, we will refer to Figures 1 to 3 The steps of the IMU installation deviation angle correction method based on the optoelectronic pod geographic tracking mode described above in this example embodiment will be explained in more detail.
[0056] In step S101, after the aircraft takes off, it hovers and flies. The electro-optical pod receives the PPS signal sent by the aircraft's GPS and sends it to the internal inertial navigation component. It waits for the inertial navigation data to output attitude information and converges the data through aircraft maneuvers.
[0057] Binding reservation target T1 geographical location P T (lon) T lat T H T The geographic tracking of target T1 requires the following input data for the entire solution process:
[0058] a) Internal inertial navigation information: Aircraft ellipsoidal altitude , yaw angle of the electro-optical pod Pitch angle of the optoelectronic pod Roll angle of the optoelectronic pod Longitude of the carrier aircraft Aircraft latitude ;
[0059] b) Target's true location: Longitude (lon) T latitude T Height H T ;
[0060] The output data is: the rotation angle of the optical pod's line of sight: azimuth angle and pitch angle.
[0061] First, transform the coordinates of the photoelectric sensor and the target point from geodetic coordinates to the photoelectric geographic coordinate system. Let the coordinates in the photoelectric geographic coordinate system be... The target geographic coordinates are The positional difference between the target and the photoelectric source is:
[0062]
[0063] The coordinates of the target in the photoelectric coordinate system are... .in This is the matrix for converting geographic coordinates to photoelectric coordinates.
[0064] Therefore, the target spatial pointing angle for geographic tracking rotation is obtained: the azimuth angle is... Pitch angle .
[0065] In steps S102 and S103, the sensor is adjusted to a suitable field of view to detect target T1, the aiming line is coarsely adjusted towards the target to ensure it hits the target, and the azimuth adjustment angle corresponding to the aiming line movement in the current field of view is calculated in real time. and pitch adjustment angle The initial IMU installation deviation angle in the photoelectric pod positioning algorithm is updated in real time.
[0066] The formula for calculating the field of view angle for each field of view is as follows:
[0067]
[0068] Then adjust the orientation angle:
[0069]
[0070] Pitch adjustment angle:
[0071] .
[0072] In steps S104 and S105, the sensor is adjusted to the minimum field of view, and the aiming line is finely adjusted so that the center of the aiming line coincides with the center of the target. The azimuth adjustment angle corresponding to the amount of movement of the aiming line in the current field of view is calculated in real time. and pitch adjustment angle The final IMU installation deviation angle in the photoelectric pod positioning algorithm is updated in real time.
[0073] Furthermore, the final IMU installation deviation angle is written into the optoelectronic pod storage chip.
[0074] In one specific embodiment, the optoelectronic pod is mounted on an aircraft.
[0075] The electro-optical pod includes optical sensors, a POS (Positioning Target), a controller, and a memory. The optical sensors enable target imaging; the POS measures the pod's heading, pitch, and roll angles, as well as its position in the Earth coordinate system. The controller performs target search and tracking, target localization, and geographic tracking algorithm calculations; the memory stores the calibrated IMU installation deviation angles.
[0076] In one embodiment, such as Figure 2 The diagram shown is a flowchart of the IMU installation deviation angle correction method based on the geographical tracking mode of the photoelectric pod.
[0077] Before takeoff, ground checks ensured that the zero-point alignment of the electro-optical pod's line of sight was basically consistent with the aircraft's nose direction. After takeoff and entering the flight path, the electro-optical pod performed geo-tracking based on the pre-set target position. The pod calculated the rotation azimuth and pitch angles in real time based on the relative positions of the aircraft and the target, achieving staring tracking of the target. The pod's sensors were adjusted to a suitable field of view where the target appeared in the frame. The frame was divided into groups of 10 pixels, and the aiming line was moved towards the target at the geo-tracking position until it was aligned with the target, completing the coarse calibration of the IMU installation deviation angle. The pod's sensors were then adjusted to the minimum field of view to further correct the geo-tracking position. When the center of the aiming line was moved to coincide with the target's center, the moved field of view angle was written as the IMU installation deviation angle into the pod's storage chip, completing the precise calibration of the IMU installation deviation angle.
[0078] like Figure 3 The diagram shown is a schematic of the IMU installation deviation angle correction method for controlling the photoelectric pod based on the geographical tracking mode of the photoelectric pod.
[0079] In one specific embodiment, the input is: local inertial navigation information: longitude: 122.1576959°, latitude: 37.93841°; altitude: 2000m, heading: 10.89°; pitch: -9.10°; roll: 0.23°;
[0080] Target location: Longitude: 122.155234°, Latitude: 37.93091°; Altitude: 100m.
[0081] The angles required for the photoelectric pod to perform geographic tracking are: azimuth: -178.45°, pitch: -74.98°.
[0082] At this point, the crosshairs of the electro-optical pod cannot completely lock onto the target after rotation. Assuming a pixel deviation of 20 in a 1920×1080 pixel image with a horizontal field of view of 1.87° and a pitch field of view of 1.5°, then, based on geographic tracking, adjust the horizontal angle by 0.019° and the pitch angle by 0.028°. At this point, the crosshairs in the center of the electro-optical pod's image will completely lock onto the target.
[0083] The above-described method for correcting IMU installation deviation angles based on the geo-tracking mode of the electro-optical pod involves several steps. First, before takeoff, ground checks ensure the zero-point orientation of the electro-optical pod's line of sight is roughly consistent with the nose direction. After takeoff and entering the flight path, the electro-optical pod performs geo-tracking based on the pre-set target position. The pod calculates the rotation azimuth and pitch angles in real-time based on the relative positions of the aircraft and the target, achieving staring tracking of the target. The pod's sensor is adjusted to a suitable field of view where the target appears in the frame. The frame is divided into groups of 10 pixels, and the aiming line is moved towards the target at the geo-tracking position until it overlaps with the target, completing the coarse calibration of the IMU installation deviation angle. The pod's sensor is then adjusted to the minimum field of view to further correct the geo-tracking position. When the center of the aiming line is moved to coincide with the target center, the shifted field of view angle is written into the pod's storage chip as the IMU installation deviation angle, completing the precise calibration of the IMU installation deviation angle. On the other hand, online calibration by continuously correcting the target geographic tracking results through image conversion of the line-of-sight angle not only makes the target positioning and geographic tracking of the electro-optical pod more accurate during the calibration flights, but also ensures the target positioning and geographic tracking effect of subsequent flights by storing the calibrated installation deviation angle, thus greatly improving the execution efficiency of flight missions.
[0084] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., in the above description indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.
[0085] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.
[0086] In the embodiments of this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.
[0087] In embodiments of this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0088] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.
[0089] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.
Claims
1. A method for correcting IMU installation deviation angle based on photoelectric pod geographic tracking mode, characterized in that, The method includes: The target's true geographical location is obtained, enabling the photoelectric pod to perform geographic tracking on the target; Adjust the photoelectric sensor to a wide field of view, perform coarse adjustment on the photoelectric pod, align the aiming line of the photoelectric pod with the target, and calculate in real time the coarse adjustment angle corresponding to the aiming line in the current field of view; wherein, the coarse adjustment angle includes azimuth coarse adjustment angle and pitch coarse adjustment angle; The coarse adjustment angle is written into the geographic tracking function as the initial IMU installation deviation angle; Adjust the photoelectric sensor to a small field of view, fine-tune the photoelectric pod, and press the aiming line of the photoelectric pod onto the target, and calculate in real time the fine adjustment angle corresponding to the aiming line in the current field of view; wherein, the fine adjustment angle includes azimuth fine adjustment angle and pitch fine adjustment angle; The fine adjustment angle is written as the final IMU installation deviation angle into the geographic tracking function and saved to the storage chip; The steps of adjusting the photoelectric sensor to a wide field of view, coarsely adjusting the photoelectric pod, aligning the aiming line of the photoelectric pod with the target, and calculating the coarse adjustment angle corresponding to the aiming line in the current field of view in real time include: Adjust the photoelectric sensor to the large field of view, divide the image into groups of 10 pixels, and move the aiming line toward the target under the geographic tracking position until it presses against the target; Acquire the coarse azimuth movement pixels, coarse pitch movement pixels, and photoelectric sensor parameters of the aiming line movement, and calculate the coarse azimuth adjustment angle and the coarse pitch adjustment angle. The expression for the coarse azimuth adjustment angle is: The expression for the pitch coarse adjustment angle is: in, To move the first azimuth of the aiming line by one pixel. The first pitch direction of the aiming line moves by one pixel. For horizontal dimensions, , The size of the photoelectric sensor, The focal length of the photoelectric sensor; The steps of adjusting the photoelectric sensor to a small field of view, fine-tuning the photoelectric pod, aligning the aiming line of the photoelectric pod with the target, and calculating the fine-tuning angle corresponding to the aiming line in the current field of view in real time include: Reduce the field of view of the photoelectric sensor, adjust the photoelectric sensor to the small field of view, and move the aiming line toward the target in the geographic tracking position until the aiming line coincides with the center of the target; The fine-tuning azimuth movement pixels and fine-tuning pitch movement pixels of the aiming line movement are obtained, and the fine-tuning azimuth adjustment angle and the fine-tuning pitch adjustment angle are calculated in combination with the parameters of the optoelectronic pod sensor. The expression for the fine adjustment angle of the azimuth is: The expression for the pitch coarse adjustment angle is: in, To fine-tune the azimuth of the aiming line, move the pixel. To fine-tune the elevation of the aiming line, move the pixel. For horizontal dimensions, , The size of the photoelectric sensor, This is the focal length of the photoelectric sensor.
2. The IMU installation deviation angle correction method based on the photoelectric pod geographic tracking mode according to claim 1, characterized in that, The step of obtaining the target's true geographical location and enabling the photoelectric pod to perform geographic tracking of the target includes: The predetermined geographical location of the target is bound together to obtain the target's location coordinates; The target's position coordinates are transformed to a geographic coordinate system, and combined with the attitude information of the electro-optical pod, the target spatial pointing angle of the electro-optical pod's rotation is obtained; wherein, the target spatial pointing angle of the electro-optical pod's rotation includes the pointing azimuth angle and the pointing pitch angle; The photoelectric pod is directed toward the target based on the target spatial pointing angle of its rotation.
3. The IMU installation deviation angle correction method based on the photoelectric pod geographic tracking mode according to claim 2, characterized in that, The step of converting the target's position coordinates to a geographic coordinate system and combining this with the attitude information of the optoelectronic pod to obtain the target spatial pointing angle of the optoelectronic pod's rotation includes: The coordinates of the optoelectronic pod and the target are transformed from geodetic coordinates to a geographic coordinate system; wherein, The coordinates of the photoelectric pod in the geographic coordinate system are: The target's coordinates in the geographic coordinate system are: Then the positional difference between the target and the photoelectric pod is: The coordinates of the target in the photoelectric coordinate system are... ;in, This is the matrix for converting geographic coordinates to photoelectric coordinates. Based on the target's coordinates in the photoelectric coordinate system, the target spatial pointing azimuth angle of the rotating photoelectric pod is obtained. and pitch angle .
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