Imaging device calibration apparatus and method, and imaging device and electronic device

Abstract

The present disclosure relates to the field of imaging device calibration. Provided are an imaging device calibration apparatus and method, and an imaging device and an electronic device. The imaging device calibration apparatus comprises a deviation analysis module and a calibration module, wherein the deviation analysis module is configured to obtain, on the basis of at least three celestial images at different spatial positions, a deviation amount between a current position and an ideal position of the rotation axis of an imaging device; and the calibration module is configured to calibrate the imaging device on the basis of the deviation amount. The imaging device calibration apparatus provided in the embodiments of the present disclosure can effectively improve the autonomy of device calibration, and from the perspective of a user end, the apparatus greatly simplifies the calibration procedure and improves the efficiency, accuracy and reliability of calibration.

Description

Calibration apparatus, methods, imaging equipment, and electronic equipment for imaging devices

[0001] Relevant publicly available cross-references

[0002] This disclosure claims priority to Chinese Patent Application No. 2025100240272, filed on January 7, 2025, entitled "Calibration Apparatus, Method, Imaging Equipment and Electronic Equipment for Imaging Devices", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of imaging equipment calibration, and more specifically, to a calibration apparatus, method, imaging equipment, and electronic equipment for imaging equipment. Background Technology

[0004] Imaging equipment, such as astronomical telescopes, plays a crucial role in astronomical observation and photography. Because astronomical objects, such as stars, planets, and galaxies, are in motion, and the Earth itself rotates, precise tracking of the objects is necessary to ensure the accuracy and clarity of observations and photographs.

[0005] During filming, current technologies typically use equatorial mounts or theodolites to track the subject. Equatorial mounts offer high-precision tracking, but are complex to operate, require cumbersome and time-consuming calibration, and have limited adaptability to extreme weather conditions. Theodolite tracking requires calibration using a level or other mechanical equipment, but this calibration process is also not simple and has limited accuracy. Therefore, the efficiency and reliability of calibration for filming equipment need to be improved.

[0006] Public content

[0007] The purpose of this disclosure is to provide a calibration device, method, imaging device, and electronic device for imaging equipment. It achieves compensation for deviations through software algorithms and a calibration method that simply adjusts the rotation axis of the imaging device to an ideal position (e.g., an absolutely vertical position, where the device is absolutely horizontal) by physical means. This overcomes the deviations that occur during the imaging process and improves the calibration efficiency and reliability.

[0008] In a first aspect, embodiments of this disclosure provide a calibration device for an imaging apparatus, the calibration device including a deviation analysis module and a calibration module; the deviation analysis module is configured to obtain the deviation between the current position and the ideal position of the rotation axis of the imaging apparatus based on at least three celestial images at different spatial locations; the calibration module is configured to calibrate the imaging apparatus based on the deviation.

[0009] In the above implementation process, the deviation analysis module of the calibration device of the imaging device provided in this embodiment calculates the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations; and calibrates the imaging device based on this deviation value. The calibration device of the imaging device provided in this embodiment compensates for the deviation through software algorithms, overcoming the deviation that occurs during imaging in calibration methods that simply adjust the rotation axis of the imaging device to the ideal position (e.g., an absolutely vertical position, where the device is absolutely horizontal) using physical means; using the imaging device calibration method provided in this embodiment to calibrate the imaging device can enhance the stability of the imaging device in tracking the target object.

[0010] Optionally, in this embodiment of the disclosure, the different spatial positions include: a first spatial position and at least two second spatial positions; the calibration device further includes an image acquisition module; the image acquisition module is configured to control the imaging device to acquire a celestial body image in the first spatial position and to acquire at least two celestial body images in the at least two second spatial positions.

[0011] Optionally, in this embodiment of the disclosure, the first spatial position and the second spatial position include spatial positions at different azimuth angles under a preset elevation angle; or, spatial positions at different elevation angles under a preset azimuth angle.

[0012] In the above implementation process, the image acquisition module of the imaging device provided in this disclosure can acquire at least three different celestial images in two different ways. Corresponding to these two different celestial image acquisition methods, the deviation analysis module and calibration module of this disclosure have different processing procedures. Therefore, the calibration device of the imaging device provided in this disclosure can provide at least two calibration methods. Through the settings of the image acquisition module, it provides accurate support for the subsequent calculation of deviation, and provides a reliable basis for the calibration of the imaging device.

[0013] Optionally, in this embodiment of the disclosure, the calibration module includes a deviation compensation unit and a device control unit; during the process of calibrating the imaging device based on the deviation amount: the deviation compensation unit is configured to use the deviation amount to compensate for the current position of the rotation axis to obtain a virtual position; the device control unit is configured to control the imaging device to operate based on the virtual position.

[0014] In the above implementation process, the deviation compensation unit of the imaging device calibration apparatus provided in this disclosure can compensate for the position of the rotating axis based on the deviation amount, ensuring that the rotating axis of the imaging device is always close to or reaches the ideal position. This avoids the complexity and errors of physical adjustment, directly obtaining the virtual position through deviation compensation, thus improving the accuracy of the calibration process. The deviation compensation unit uses the calculated deviation amount to accurately compensate for the position of the rotating axis of the imaging device through mathematical methods, ensuring that the rotating axis of the imaging device can operate in the ideal position, greatly avoiding image distortion or deviation caused by an undesirable position of the rotating axis. Furthermore, the imaging device calibration apparatus provided in this disclosure is algorithm-based, enabling the rotating axis of the imaging device to be quickly adjusted to the ideal position without relying on repeated physical adjustments. This reduces errors caused by manual adjustment and improves the overall system efficiency, especially in applications requiring multiple calibrations or high-frequency observations, enabling fast and efficient calibration.

[0015] Optionally, in this embodiment of the disclosure, the deviation includes a first deviation between the current position of the rotation axis and the absolute vertical position. When the deviation is the first deviation, the deviation compensation unit is configured to use the first deviation to compensate for the current position of the rotation axis to obtain the virtual horizontal position of the imaging device. The device control unit is specifically configured to control the theodolite of the imaging device to work in the virtual horizontal position.

[0016] In the above implementation process, the calibration module of the imaging device calibration apparatus provided in this disclosure replaces physical adjustment with a virtual horizontal position, making the calibration process more efficient. The device does not need to perform frequent physical adjustments; it only needs to operate based on the virtual horizontal GPS position, thereby reducing debugging time and workload and improving calibration efficiency.

[0017] Optionally, in this embodiment of the disclosure, the calibration module further includes: a virtual level monitoring unit; the virtual level monitoring unit is configured to monitor whether the amount of horizontal change of the virtual level of the imaging device operating in a virtual position exceeds a horizontal change threshold; and generate a recalibration signal if the amount of horizontal change of the virtual level exceeds the horizontal change threshold.

[0018] Optionally, in this embodiment of the disclosure, the range of the horizontal change threshold includes [3°, 6°].

[0019] In the above implementation process, the calibration device for the imaging equipment provided in this embodiment of the present disclosure, by setting a virtual level monitoring unit, ensures that once the virtual level change of the equipment exceeds a set threshold, the virtual level monitoring unit generates a recalibration signal, triggering an automatic calibration process, thus ensuring that the virtual level position of the equipment remains stable. This guarantees that the equipment can maintain high-precision level calibration during long-term operation or in changing environments. The virtual level monitoring unit provides the imaging equipment with a dynamic correction function, enabling the equipment to cope with level deviations caused by external disturbances or internal wear. By setting a reasonable level change threshold, timely correction can be performed when the equipment malfunctions, enhancing the system's fault tolerance and avoiding major errors caused by the accumulation of minor deviations.

[0020] Optionally, in this embodiment of the disclosure, the deviation includes a second deviation between the current position of the rotation axis and the position of the North Celestial Pole in the same coordinate system. When the deviation is the second deviation, the deviation compensation unit is configured to use the second deviation to compensate for the current position of the rotation axis to obtain the virtual North Pole position of the imaging device. The device control unit is configured to generate a device control signal including the second deviation and / or the virtual North Pole position.

[0021] In the above implementation process, the calibration module obtains the virtual north pole position of the imaging device by compensating for the deviation of the rotation axis. With the virtual north pole position, the theodolite can simulate the working mode of an equatorial mount, greatly improving the applicability and accuracy of the device. Especially in astronomical imaging, it can largely avoid field rotation, achieving better imaging results. This not only reduces the cost of hardware adjustments and improves imaging quality but also enhances the overall performance and application range of the imaging device.

[0022] Optionally, in this embodiment of the disclosure, in the process of obtaining the deviation between the current position and the ideal position of the rotation axis of the imaging device based on at least three celestial images at different spatial locations, the deviation analysis module is configured to: obtain the coordinate positions of the three celestial images in the equatorial coordinate system based on the three celestial images at different spatial locations; convert the coordinate positions in the equatorial coordinate system to coordinate positions in the rectangular coordinate system, and calculate the normal vector of the plane formed by the three coordinate positions in the rectangular coordinate system; convert the normal vector in the rectangular coordinate system to coordinate positions in the horizontal coordinate system to obtain the horizontal coordinates of the rotation axis; and obtain the deviation of the rotation axis based on the horizontal coordinates of the rotation axis and the standard horizontal coordinates of the rotation axis in an absolutely vertical position.

[0023] In the above implementation process, the calibration device of the imaging device provided in this embodiment of the present disclosure sets up a deviation analysis module, which can accurately obtain the first deviation between the current position of the rotation axis of the imaging device and the absolute vertical position by analyzing the position of the celestial body in the celestial image and combining coordinate transformation and geometric calculation. The first deviation is configured to compensate for the position of the rotation axis of the device, so that the rotation axis of the imaging device can be in the ideal horizontal position.

[0024] Optionally, in this embodiment of the disclosure, the deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in an absolutely vertical position. In the process of obtaining the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations, the deviation analysis module is specifically configured to: use the first celestial image as a reference image and obtain a reference origin; acquire at least two sets of commanded position coordinates and actual position coordinates of the second celestial image relative to the reference origin; wherein, the commanded position coordinates characterize the position coordinates of the second celestial image acquired by the imaging device when the rotation axis of the imaging device is in an absolutely vertical position, and the actual position coordinates characterize the coordinate position of the second celestial image acquired by the imaging device when the rotation axis of the imaging device is in its current position; and calculate the third deviation based on the commanded position coordinates and actual position coordinates of the at least two sets of second celestial images.

[0025] Optionally, in this embodiment of the disclosure, during the process of calculating the third deviation based on the command position coordinates and actual position coordinates of at least two sets of celestial images, the deviation analysis module is specifically configured to: calculate the transformation matrix from the command position coordinates to the actual position coordinates based on the command position coordinates and actual position coordinates of at least two sets of celestial images; and calculate the inverse matrix of the transformation matrix to obtain the third deviation.

[0026] Optionally, in this embodiment of the disclosure, when the deviation is a third deviation: the deviation compensation unit is configured to use the third deviation to compensate for the current position of the rotation axis and obtain virtual command coordinates; the device control unit is specifically configured to control the imaging device to work under the virtual command coordinates during the imaging process of the imaging device.

[0027] In the above implementation process, the calibration device for the imaging equipment provided in this disclosure can perform real-time calibration before each imaging operation. By applying the inverse matrix of the transformation matrix, the current position of the actual rotation axis of the imaging equipment (i.e., the current coordinates of the rotation axis) can be converted into the ideal position of the rotation axis, thereby generating virtual command coordinates. This effectively compensates for the difference between the actual and ideal positions of the rotation axis caused by deviations in the rotation axis, thus achieving real-time calibration of the imaging equipment and ensuring the accuracy and stability of the imaging after calibration.

[0028] Secondly, embodiments of this disclosure provide a calibration method for an imaging device. The calibration method includes: obtaining the deviation between the current position and the ideal position of the rotation axis of the imaging device based on at least three celestial images at different spatial locations; and calibrating the imaging device based on the deviation.

[0029] Optionally, in this embodiment of the disclosure, the deviation includes a first deviation between the current position of the rotation axis and the absolute vertical position; calibrating the imaging device based on the deviation includes: using the first deviation to compensate for the current position of the rotation axis to obtain a virtual horizontal position of the rotation axis; and controlling the theodolite to operate in the virtual position.

[0030] Optionally, in this embodiment of the disclosure, the deviation includes a second deviation between the current position of the rotation axis and the position of the North Celestial Pole in the same coordinate system; calibrating the imaging device based on the deviation includes: using the second deviation to compensate for the current position of the rotation axis to obtain a virtual North Pole position of the imaging device; and generating a device control signal including the second deviation and / or the virtual North Pole position.

[0031] Optionally, in this embodiment of the disclosure, the deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in an absolutely vertical position; calibrating the imaging device based on the deviation includes: using the third deviation to compensate for the current position of the rotation axis to obtain virtual commanded coordinates; and controlling the imaging device to image under the virtual commanded coordinates during the imaging process.

[0032] Thirdly, embodiments of this disclosure provide an imaging device, which includes: an imaging module, a theodolite, and a controller; the imaging module and the theodolite are connected to the controller; the imaging module is configured to acquire at least three celestial images at different spatial locations and send the celestial images to the controller; the controller is configured to compensate for the current position of the rotation axis based on the celestial images to obtain an imaging virtual position and send the virtual position to the theodolite; the theodolite is configured to receive the virtual position.

[0033] In the above implementation process, the imaging device provided in this disclosure achieves rotation axis calibration based on celestial images through the coordinated operation of the imaging module, theodolite, and controller. The imaging module acquires celestial images at different spatial locations and sends them to the controller. The controller compensates for the current position of the rotation axis based on these images, calculates a virtual position, and sends this virtual position to the theodolite. After receiving the virtual position, the theodolite calibrates the imaging device. This imaging device can effectively compensate for the physical position deviation of the device's rotation axis, ensuring that the imaging device can accurately align with the target, thus improving the device's positioning accuracy and imaging effect.

[0034] Fourthly, embodiments of this disclosure provide an electronic device, which includes a memory and a processor. The memory stores program instructions, and when the processor executes the program instructions, it performs steps in any implementation of the calibration method for the imaging device described above.

[0035] Fifthly, embodiments of this disclosure provide a computer program product, the computer program product including a computer program / instructions, which are executed by a processor as steps in any implementation of the calibration method for the imaging device described above.

[0036] Sixthly, embodiments of this disclosure also provide a computer-readable storage medium storing computer program instructions, which, when read and executed by a processor, perform steps in any implementation of the calibration method for the imaging device described above. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments of this disclosure will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 is a first schematic diagram of the module of the calibration device for the imaging equipment provided in an embodiment of this disclosure;

[0039] Figure 2 is a second schematic diagram of the module of the calibration device for the imaging equipment provided in the embodiments of this disclosure;

[0040] Figure 3 is a calibration flowchart of the imaging device provided in this disclosure;

[0041] Figure 4 is a flowchart of a first calibration example provided in this embodiment of the present disclosure;

[0042] Figure 5 is a flowchart of a second calibration example provided in this disclosure;

[0043] Figure 6 is a flowchart of a third calibration example provided in this disclosure;

[0044] Figure 7 is a schematic diagram of the structure of the electronic device provided in the embodiments of this disclosure.

[0045] Icons: Calibration device for imaging equipment - 100; Image acquisition module - 110; Deviation analysis module - 120; Calibration module - 130; Deviation compensation unit - 131; Equipment control unit - 132; Virtual level monitoring unit - 133; Electronic equipment - 200; Processor - 201; Memory - 202. Detailed Implementation

[0046] The technical solutions of the embodiments of this disclosure will now be described with reference to the accompanying drawings. For example, the flowcharts and block diagrams in the drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, program segment, or part of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or can be implemented using a combination of dedicated hardware and computer instructions. In addition, the functional modules in the various embodiments of this disclosure may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0047] Imaging equipment, such as astronomical telescopes, plays a crucial role in astronomical observation and photography. Because astronomical objects, such as stars, planets, and galaxies, are in motion, and the Earth itself rotates, their positions change over time. To ensure accuracy in observation and photography, these celestial bodies need to be tracked in real time. Furthermore, the Earth's rotation causes the position of the observed target relative to the ground-based observation point to change. To maintain continuous observation and photography of the target, the effects of the Earth's rotation must also be considered during the imaging process. Additionally, in astronomy, long exposures are often required to capture faint celestial signals or conduct in-depth observations. This necessitates that the imaging equipment maintain stable tracking of the target during the exposure. Therefore, precise tracking of the subject is essential to ensure the accuracy and clarity of observation and photography.

[0048] In existing technologies, tracking of the subject is usually achieved using an equatorial mount or a theodolite.

[0049] The equatorial mount was designed to improve upon the shortcomings of altazimuth mounts, its main purpose being to overcome the influence of the Earth's rotation on stargazing. The equatorial mount has two mutually perpendicular axes of rotation, called the right ascension axis and the declination axis. When using the equatorial mount, the right ascension axis must first be aligned parallel to the Earth's rotation axis. By aligning its rotation axis parallel to the Earth's rotation axis, the telescope can rotate synchronously with the Earth's rotation, thus achieving stable tracking of celestial bodies.

[0050] However, tracking objects using an equatorial mount is relatively complex and requires specialized knowledge and experience. Because equatorial mount calibration involves multiple steps and details, the entire process can be time-consuming. Furthermore, equatorial mounts are typically large and heavy, making them inconvenient to carry and move, limiting their use outdoors or far from fixed observation points. Additionally, the calibration accuracy of an equatorial mount can be affected by environmental factors such as temperature, humidity, and air pressure. These changes can alter the mount's calibration status, thus affecting the accuracy of observations.

[0051] Theodolites are widely used photoelectric surveying instruments in fields such as aerospace, geographical surveying, land resource mapping, and oil exploration. The tracking capability of a theodolite relies primarily on its internal precision mechanical structure and optical system, as well as its built-in level or other calibration components. Before use, theodolites need to be calibrated. First, the theodolite must be correctly mounted on a tripod or other stable support to ensure stability and minimize external interference. Then, using the level or other calibration components on the theodolite, preliminary horizontal and vertical adjustments are made to ensure the accuracy of its measurement and tracking.

[0052] Theodolite's tracking is based on its angle measurement principle. It determines the target point's position and orientation by accurately measuring the relative positional relationship (i.e., horizontal and altitude angles) between the target point and a reference point. During tracking, the theodolite's telescope continuously points at the target, while its internal angle measurement system records and updates the target's position information in real time.

[0053] However, when using a tripod and theodolite together, if the ground is not perfectly level, the theodolite's rotation plane will not be horizontal during its rotation around its horizontal axis, and the axis will not point towards the GPS-positioned center of the Earth. This "horizontal rotation" in a non-horizontal state is actually accompanied by changes in altitude, thus affecting the stability of tracking. To meet the requirements of theodolite tracking celestial bodies, the rotation speed of the elevation angle and horizontal direction angle must be calculated independently. This calculation is mainly based on GPS coordinates, time, and the specific object to be observed, and is crucial to ensuring that the equipment can accurately and stably track the target. Therefore, when the tripod and theodolite are not level on the ground, the altitude change caused by its horizontal rotation becomes a significant problem, affecting the accuracy and stability of tracking.

[0054] Based on this, this disclosure proposes a calibration device, method, imaging device, and electronic device for imaging equipment. The calibration device includes a deviation analysis module and a calibration module. The deviation analysis module can obtain the deviation between the current position and the ideal position of the imaging device's rotation axis based on different celestial images. After obtaining the deviation, the calibration module assigns a virtual position to the imaging device based on this deviation, enabling the imaging device to operate based on this virtual position. The calibration device for imaging equipment provided by this disclosure can effectively improve the autonomy of equipment calibration, greatly simplifying the calibration process for users and improving the efficiency, accuracy, and reliability of calibration.

[0055] Please refer to Figure 1. Figure 1 is a first schematic diagram of the module of the calibration device for an imaging device provided in the embodiment of this disclosure. This disclosure provides a calibration device 100 for an imaging device, which includes a deviation analysis module 120 and a calibration module 130.

[0056] The deviation analysis module 120 is configured to obtain the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations.

[0057] The calibration module 130 is configured to calibrate the imaging device based on the deviation.

[0058] In the above implementation process, the deviation analysis module 120 acquires at least three celestial images at different spatial locations at the current position, and processes and analyzes these three celestial images at different spatial locations to obtain the deviation between the current position and the ideal position of the imaging device's rotation axis.

[0059] In this embodiment of the disclosure, the ideal position is the desired location of the rotation axis of the imaging device, such as an absolutely vertical position (in which case the imaging device is absolutely horizontal), or other positions. It should be noted that the ideal position is the position of the rotation axis of the imaging device, not the position of the imaging device itself; when the rotation axis of the imaging device is absolutely vertical, the imaging device is in an absolutely horizontal position.

[0060] The current position of the rotation axis is the position of the rotation axis when the imaging device is in its current position. It should be noted that the current position of the device is not the current position of the rotation axis.

[0061] The celestial images obtained by the deviation analysis module 120 are from different locations, such as three celestial images at different altitude angles and azimuth angles, or three celestial images at the same altitude angle but different azimuth angles, or three celestial images at the same azimuth angle but different altitude angles.

[0062] The deviation analysis module 120 analyzes at least three celestial images at different spatial locations to obtain the deviation between the current position of the imaging device's rotation axis and its ideal position (the desired position of the imaging device's rotation axis). Based on this deviation, the calibration module 130 obtains a virtual position and assigns this virtual position to the imaging device, making the imaging device believe that its rotation axis is currently in the aforementioned ideal position. It should be emphasized that the calibration module 130 of the imaging device calibration device 100 provided in this embodiment of the present disclosure assigns a virtual position to the imaging device. Under this virtual position, the device's rotation axis is in the ideal position, and the imaging device is also in a virtual ideal position, but the imaging device itself will never reach this virtual ideal position.

[0063] Therefore, the deviation analysis module 120 of the imaging device calibration apparatus provided in this embodiment calculates the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations; and calibrates the imaging device based on this deviation value. The imaging device calibration apparatus 100 provided in this embodiment compensates for the deviation through software algorithms, overcoming the deviation that occurs during imaging in calibration methods that simply adjust the rotation axis of the imaging device to the ideal position (e.g., an absolutely vertical position) using physical means; using the imaging device calibration method provided in this embodiment to calibrate the imaging device can enhance the stability of the imaging device in tracking the target object.

[0064] Please refer to Figure 2, which is a second schematic diagram of the module of the calibration device for the imaging equipment provided in this embodiment of the present disclosure; as shown in Figure 2, the calibration device for the imaging equipment provided in this embodiment of the present disclosure further includes an image acquisition module 110. The aforementioned different spatial positions include a first spatial position and at least two different second spatial positions.

[0065] In this embodiment of the disclosure, the image acquisition module 110 is configured to control the imaging device at a first spatial position to acquire a first celestial body image, and to acquire at least two second celestial body images at at least two second spatial positions.

[0066] In other words, the acquisition method of at least three celestial body images at different spatial locations obtained by the image acquisition module 110 can be as follows: acquiring one celestial body image at the first spatial location, which can be used as the base image; or the image acquisition module 110 or the operator controls the imaging device to rotate, thereby acquiring at least two different celestial body images at at least two different spatial locations.

[0067] In a first possible implementation, the first spatial position and the second spatial position include spatial positions at different azimuth angles under a preset elevation angle; or, spatial positions at different elevation angles under a preset azimuth angle.

[0068] The first celestial body image is captured at a specific elevation angle. Then, the rotation axis is controlled to rotate horizontally to two different horizontal angle positions (i.e., the second spatial positions mentioned above) at that specific elevation angle, thereby acquiring two second celestial body images. Alternatively, the first celestial body image is captured at a specific horizontal angle. Then, the rotation axis is controlled to rotate vertically to two different elevation angle positions (i.e., the second spatial positions mentioned above) at that specific horizontal angle, thereby acquiring two second celestial body images.

[0069] For example, assuming the operator is outdoors and wants to calibrate the imaging device, the operator first needs to raise the lens of the imaging device to a certain elevation angle as the initial position (e.g., 30 degrees) and take an image of the first celestial body from this initial position. After taking the first celestial body image, the operator controls the azimuth angle of the imaging device to rotate twice (e.g., 15 degrees each time) to obtain two different images of the second celestial body.

[0070] For example, suppose the operator is indoors, such as on a balcony, and is acquiring celestial images through a window. In this case, the operator's available angles through the window are limited. It is recommended that the operator first take one image of the celestial body from the center of the window, and then perform multiple changes in elevation or azimuth angles to obtain at least two more images of the celestial body.

[0071] In the above implementation process, the elevation angle ranges from 0° to 90°, and the azimuth angle ranges from 0° to 120°. During the process of capturing images of the second celestial body, the changes in elevation or azimuth angle can be regular, such as an arithmetic progression; or they can be irregular, for example, changing from an azimuth (or elevation) angle of 30 degrees to 50 degrees, and then from 50 degrees to 60 degrees.

[0072] In a second possible implementation, an image of the first celestial body is captured at a first spatial position, and the horizontal and vertical angles of the rotation axis of the imaging device are changed to obtain an image of the second celestial body; the horizontal and vertical angles of the rotation axis of the imaging device are changed again to obtain another image of the second celestial body.

[0073] For example, the operator takes a picture of the first celestial body from a first spatial position, and then rotates the axis of rotation to change both the elevation and horizontal angles to obtain a picture of the second celestial body. In the current embodiment, the requirements for rotation are lower, often involving random rotation, and rotation in a specific direction is not required.

[0074] Therefore, it can be seen that the image acquisition module 110 of the imaging device provided in this embodiment can acquire at least three different celestial images in two different ways. Corresponding to these two different celestial image acquisition methods, the deviation analysis module 120 and calibration module 130 of this disclosure have different processing procedures. Therefore, the calibration device of the imaging device provided in this embodiment can provide at least two calibration methods. Through the settings of the image acquisition module 110, accurate support is provided for the subsequent calculation of deviation, providing a reliable basis for the calibration of the imaging device.

[0075] Please continue referring to Figure 2. In an optional embodiment of this disclosure, the calibration module 130 in the calibration device of the imaging equipment provided in this embodiment includes a deviation compensation unit 131 and a device control unit 132. Regarding the first embodiment of celestial image acquisition described above, during the process of calibrating the imaging equipment based on the deviation amount:

[0076] The deviation compensation unit 131 is configured to use the deviation amount to compensate for the current position of the rotating axis and obtain a virtual position.

[0077] The device control unit 132 is configured to control the imaging device to operate in a virtual location.

[0078] In the above implementation process, the deviation compensation unit 131 compensates for the current position of the rotating axis based on the calculated deviation between the current position and the ideal position of the rotating axis of the imaging device, obtains a virtual position, and sends this virtual position to the device control unit 132. After receiving the virtual position, the device control unit 132 controls the imaging device to work based on the virtual position, thereby completing the calibration of the device.

[0079] In this embodiment of the disclosure, since the deviation is calculated in real time from the image data, the device can be dynamically calibrated under different observation conditions. When the imaging device encounters different errors or deviations, the deviation compensation unit 131 can automatically calculate the deviation of the desired ideal position based on the current position and the ideal position of the imaging device's rotation axis, and use this deviation to compensate for the current position, thereby ensuring that the imaging device always maintains its optimal working state.

[0080] In this embodiment of the disclosure, the virtual position is a quantity generated based on the deviation between the current position and the ideal position of the imaging device's rotation axis, and by compensating for the current position of the rotation axis. In some cases, the virtual position refers to a virtual coordinate position assigned to the imaging device (i.e., a virtual location of the device). In other cases, the virtual position refers to the position where the imaging device is controlled to image (a position in the celestial sphere), and can also be understood as the coordinate position to which the imaging device's equatorial mount or theodolite needs to move.

[0081] Therefore, the deviation compensation unit 131 of the imaging device calibration apparatus 100 provided in this embodiment can compensate for the position of the rotating axis based on the deviation amount, ensuring that the rotating axis of the imaging device is always close to or reaches the ideal position. This avoids the complexity and errors of physical adjustment, directly obtaining a virtual position through deviation compensation, and enabling the imaging device to operate based on this virtual position, thus improving the accuracy of the calibration process. The deviation compensation unit 131 uses the calculated deviation amount to accurately compensate for the position of the rotating axis through mathematical methods, ensuring that the rotating axis of the imaging device can operate in the ideal position, greatly avoiding image distortion or deviation caused by an undesirable position of the rotating axis. Furthermore, the imaging device calibration apparatus 100 provided in this embodiment is based on an algorithm, enabling the rotating axis of the imaging device to be quickly adjusted to the ideal position without relying on repeated physical adjustments. This reduces errors caused by manual adjustment and improves the overall system efficiency, especially in applications requiring multiple calibrations or high-frequency observations, enabling fast and efficient calibration.

[0082] In an optional embodiment of this disclosure, the deviation includes a first deviation between the current position of the rotation axis and its absolute vertical position. The calibration device for the imaging apparatus provided in this disclosure is most commonly used for the horizontal calibration of the imaging apparatus. That is, the deviation is the difference between the current horizontal position of the rotation axis and the desired absolute vertical position, which is referred to here as the first deviation.

[0083] When the deviation is the first deviation:

[0084] The deviation compensation unit 131 is configured to use a first deviation amount to compensate for the current position of the rotation axis to obtain the virtual horizontal position of the imaging device. The device control unit 132 is specifically configured to control the theodolite of the imaging device to operate in the virtual horizontal position.

[0085] After the deviation analysis module 120 obtains the first deviation between the current position of the rotation axis and the absolute vertical position, the compensation unit uses the first deviation to compensate for the current position, obtaining a virtual absolute horizontal GPS for the imaging device (under this virtual absolute horizontal GPS, the rotation axis of the imaging device is absolutely vertical). Further, this virtual horizontal position is given to the theodolite of the imaging device, allowing the theodolite to operate under this virtual horizontal position, thereby completing the calibration of the imaging device. Before the theodolite begins the tracking process, this virtual GPS is given to the theodolite control device, causing the control device to control the horizontal and vertical rotation according to the tracking mode of the target under the virtual GPS.

[0086] This section briefly explains the process of obtaining the virtual horizontal position of the imaging device based on the current position of the rotation axis after compensating for the first deviation. Assuming a first deviation is obtained, this first deviation is substituted with the geographical location of the imaging device, and then converted into a virtual horizontal position for the imaging device. In this virtual horizontal position, the rotation axis can be considered absolutely vertical.

[0087] For example, suppose the rotation axis of the imaging device is currently located at position A, but the rotation axis of the imaging device at position A is not absolutely vertical; the image acquisition module 110 obtains three different celestial images at position A through the first image acquisition method described above; the deviation analysis module 120 analyzes these three different celestial images to obtain a first deviation between position A and the absolutely vertical position of the rotation axis of the imaging device; the deviation compensation unit 131 uses the first deviation to compensate position A to obtain a virtual horizontal position where the device is absolutely horizontal, assuming it is position B; position B is given to the theodolite, making it believe that the device is currently at position B, and the algorithm deceives the device into believing that the rotation axis of the device is absolutely vertical at the current position.

[0088] Therefore, it can be seen that the calibration module 130 of the imaging device calibration apparatus 100 provided in this embodiment replaces physical adjustment with virtual horizontal position, making the calibration process more efficient. The device does not need to perform frequent physical adjustments, but only needs to work according to the virtual horizontal GPS position, thereby reducing debugging time and workload and improving calibration efficiency.

[0089] In an optional embodiment, referring to FIG2, the calibration module 130 of the calibration device for the imaging equipment provided in this embodiment of the present disclosure further includes: a virtual level monitoring unit 133.

[0090] The virtual level monitoring unit 133 is configured to monitor whether the amount of horizontal change of the virtual level of the imaging device operating in a virtual position exceeds a horizontal change threshold; and to generate a recalibration signal if the amount of horizontal change of the virtual level exceeds the horizontal change threshold.

[0091] In the above implementation process, after the imaging equipment is calibrated, its horizontal position may change again during operation due to factors such as changes in the external environment, equipment vibration, or mechanical deformation. The virtual level monitoring unit 133 monitors in real time whether the virtual level of the equipment has changed by an amount exceeding the level change threshold. If it exceeds the level change threshold, the virtual level monitoring unit 133 generates a recalibration signal and sends it to the control center of the imaging equipment calibration device 100, thereby recalibrating the equipment's level.

[0092] It should be noted that, since the calibration device 100 for the imaging device provided in this embodiment does not actually change the position of the imaging device during calibration, but rather performs deviation compensation in the algorithm; since the position of the imaging device itself does not change, the physical position of the imaging device is not horizontal. Therefore, in this embodiment, the position of the imaging device after calibration by the calibration device is regarded as the virtual horizontal position of the device.

[0093] Optionally, the range of the horizontal change threshold includes [3°, 6°]. For example, assuming the horizontal change threshold is 5°, and after the imaging device is calibrated, assuming the virtual horizontal level after calibration is 10°, during the operation of the imaging device, the virtual horizontal monitoring unit 133 monitors the change of the virtual horizontal level in real time. If it exceeds 15° or falls below 5°, the virtual horizontal monitoring unit 133 will generate a recalibration signal to inform the device that recalibration is required.

[0094] Therefore, the calibration device for the imaging equipment provided in this embodiment utilizes a virtual level monitoring unit 133. Once the virtual level change exceeds a set threshold, the virtual level monitoring unit 133 generates a recalibration signal, triggering an automatic calibration process. This ensures the virtual level position of the equipment remains stable, thereby guaranteeing high-precision level calibration during long-term operation or in changing environments. The virtual level monitoring unit 133 provides dynamic correction functionality for the imaging equipment, enabling it to cope with level deviations caused by external disturbances or internal wear. By setting a reasonable level change threshold, timely correction can be performed when equipment malfunctions, enhancing system fault tolerance and preventing significant errors caused by the accumulation of minor deviations.

[0095] In an optional embodiment, still referring to the first method of acquiring celestial images described above, the deviation includes a second deviation where the current position of the rotation axis is in the same coordinate system as the position of the North Celestial Pole.

[0096] When the deviation is the second deviation:

[0097] The deviation compensation unit 131 is configured to use a second deviation amount to compensate for the current position of the rotation axis to obtain a virtual north pole position of the imaging device. The device control unit 132 is configured to generate a device control signal that includes the second deviation amount and / or the virtual north pole position.

[0098] In the above implementation process, the second deviation reflects the difference between the current position of the rotation axis and the position of the North Celestial Pole. It can be an angle or coordinate offset, reflecting the deviation of the device's rotation axis from the ideal direction (North Celestial Pole).

[0099] The deviation compensation unit 131 uses a second deviation amount to compensate for the current position of the rotation axis, thereby obtaining the virtual north pole position of the imaging device. In other words, the deviation compensation unit 131 obtains a virtual position based on the acquired celestial image, simulating the device's current position at the geographic North Pole (where the horizontal rotation axis points towards the North Celestial Pole). When the theodolite is informed that it is located at the geographic North Pole, based on the device control signal, the horizontal rotation axis is pointed towards the North Celestial Pole (either through a clamping device or manual rotation). The theodolite rotates in the manner that the device is at the geographic North Pole, thus enabling the theodolite to be reused as an equatorial mount.

[0100] After the compensation process is complete, the device control unit 132 generates a control signal containing a second deviation amount and / or a virtual north pole position. The control signal guides the imaging device to operate at the virtual north pole position.

[0101] For a theodolite, this means that without changing the hardware structure, it can perform operations similar to an equatorial mount through compensation. Before using an equatorial mount, there is an operation to align the polar axis (right ascension axis), that is, to point the right ascension axis to the North Celestial Pole, and then lock the position of the right ascension axis (the direction of the right ascension axis remains unchanged, but the device can rotate around the right ascension axis); then adjust the right ascension and declination to find the target to be tracked, and then simply rotate the device around the right ascension axis to achieve target tracking.

[0102] The equatorial mount mode is used in conjunction with external equipment. The horizontal rotation axis of the theodolite points to the North Celestial Pole (if the equipment is placed at the North Pole and is absolutely horizontal, its horizontal rotation axis will also point to the North Celestial Pole). Then, the horizontal rotation axis is equivalent to the right ascension axis of the equatorial mount. Once aligned with the target, you only need to rotate the horizontal rotation axis to achieve the effect of rotating the right ascension axis on the equatorial mount. This allows the theodolite to be reused as an equatorial mount.

[0103] It is worth noting that since theodolites can only rotate on the horizon, even if the theodolite always keeps the tracked target in the center of the image, the image will still rotate, i.e., field spin will occur. However, the calibration device of the imaging equipment provided in this embodiment can reuse the theodolite as an equatorial mount. After conversion, the entire device rotates around the North and South Poles (at which point the polar axis points to the North Poles) (in line with the Earth's rotation center), so the image will not rotate.

[0104] Therefore, the calibration module 130, through deviation compensation of the rotation axis, enables the theodolite to simulate the working mode of an equatorial mount, greatly improving the applicability and accuracy of the equipment. Especially in astronomical imaging, it can largely avoid field rotation and achieve better imaging results. This not only reduces the cost of hardware adjustments and improves imaging quality but also enhances the overall performance and application range of the imaging equipment.

[0105] In an optional embodiment, during the process of obtaining the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations, the deviation analysis module 120 is configured to:

[0106] Based on three celestial images from different spatial locations, the coordinates of the three celestial images in the equatorial coordinate system are obtained.

[0107] Convert the coordinate positions in the equatorial coordinate system to the coordinate positions in the rectangular coordinate system, and calculate the normal vector of the plane formed by the three coordinate positions in the rectangular coordinate system.

[0108] Convert the normal vector in the Cartesian coordinate system to the coordinate position in the horizontal coordinate system to obtain the horizontal coordinates of the rotation axis.

[0109] The deviation of the rotation axis is obtained based on the horizontal coordinates of the rotation axis and the standard horizontal coordinates of the rotation axis when it is in an absolutely vertical position.

[0110] In the above implementation process, the positions of three celestial images in the equatorial coordinate system are obtained from three celestial images located at different spatial positions. Each celestial image corresponds to a celestial coordinate in the equatorial coordinate system, usually represented as right ascension (RA) and declination (Dec). Assume the celestial coordinates corresponding to the three images are: equatorial coordinates of the first celestial image: (RA1, Dec1); equatorial coordinates of the second celestial image: (RA2, Dec2); and equatorial coordinates of the third celestial image: (RA3, Dec3). In the equatorial coordinate system, these coordinates are spherical coordinates, which can be converted to Cartesian coordinates in a rectangular coordinate system. Right ascension (RA) and declination (Dec) correspond to longitude and latitude in the spherical coordinate system, respectively.

[0111] To obtain the coordinates of a celestial body image in the equatorial coordinate system, the following method can be used: Randomly select two stars and construct a circular region based on the diameter of the line connecting them. Within this region, select two more stars to form a first four-star combination and calculate its corresponding first geometric hash code. Then, divide the reference star table into a grid. From each grid, select the brightest stars and form a second four-star combination with four of them, calculating its corresponding second geometric hash code. Finally, compare the difference between the first and second geometric hash codes. If the difference is within a preset second threshold, the first and second four-star combinations are considered a successful match. When the number of successfully matched combinations within a grid exceeds a preset third threshold, the image is determined to be located within the corresponding celestial region. Based on the correspondence of the successfully matched combinations, the right ascension and declination coordinates of the celestial body image's center point are obtained. This implementation is merely exemplary; other locations within the celestial body image can also be selected as its coordinates.

[0112] The coordinates (RAi,Deci) of each celestial image in the equatorial coordinate system are converted to the coordinates (xi,yi,zi) in the rectangular coordinate system by using the formulas x=cos(Dec)·cos(RA), y=cos(Dec)·sin(RA), z=sin(Dec).

[0113] For example, suppose we have a first celestial image (RA1 = 10°, Dec1 = 20°), a second celestial image (RA2 = 50°, Dec2 = 20°), and another second celestial image (RA3 = 90°, Dec3 = 20°). Right ascension and declination are given in degrees, but calculations usually require converting these degrees to radians. The calculation process is as follows: RA1 = 10° = 10π / 180 radians ≈ 0.1745 radians. x1=cos(0.3491)cos(0.1745)≈0.9255, y1=cos(0.3491)·sin(0.1745)≈0.1636, z1=sin(0.3491)≈0.3420, (x1, y1, z1)=(0.9255,0.1636,0.3420),

[0114] Similarly, the other two coordinates are calculated as follows: (x2, y2, z2) = (0.6047, 0.7204, 0.3420), (x3, y3, z3) = (0, 0.9397, 0.3420).

[0115] The coordinate positions in the Cartesian coordinate system are obtained as follows: (x1, y1, z1), (x2, y2, z2), (x3, y3, z3). Further, calculate the normal vector of the plane formed by the three coordinate positions in the Cartesian coordinate system.

[0116] First, calculate the vector from (x1, y1, z1) to (x2, y2, z2). And the vector from (x2, y2, z2) to (x3, y3, z3). Calculate vectors and The cross product can yield the normal vector. Right now, For example, using (x1, y1, z1) = (0.9255, 0.1636, 0.3420) and (x2, y2, z2) = (0.6047, 0.7204, 0.3420), the normal vector is calculated as follows: Then, the normal vector in the rectangular coordinate system is converted into the coordinate position in the horizontal coordinate system to obtain the horizontal coordinates of the rotation axis.

[0117] The horizontal coordinate system (Altitude-Azimuth, or Alt-Az for short) has two components: the az azimuth component and the alt altitude component. The azimuth component is the angle measured clockwise from north, typically calculated from north to east (0° is north, 90° is east, 180° is south, and 270° is west). The azimuth component represents the altitude of a celestial body relative to the horizontal plane, ranging from -90° (zenith) to +90° (horizontal plane).

[0118] To calculate the horizontal coordinates of the rotation axis (normal vector), we first need to calculate the angle between the normal vector and the zenith, i.e., the zenith angle; the formula is: The azimuth angle (az) and altitude angle (alt) are calculated based on the projection of the normal vector onto the celestial sphere. The formula is as follows: alt = 90° - θ.

[0119] Assuming the calculated normal vector The horizon coordinates are (az, alt). If the imaging device is absolutely horizontal, then the horizon coordinates of the rotation center should be (0, 90°); therefore, the first deviation in the horizon coordinate system is Diff. az =az, Diff alt =90-alt; In this embodiment of the disclosure, the final first deviation is the value converted from the horizon coordinates to GPS; that is, Diff Lat =cos(Diff az )*Diff alt Diff Lon =sin(Diff az )*Diff alt .

[0120] Therefore, it can be seen that the calibration device of the imaging equipment provided in this embodiment of the present disclosure, by setting up the deviation analysis module 120, can accurately obtain the first deviation between the rotation axis of the imaging equipment and the absolute vertical position by analyzing the position of celestial bodies in the celestial image and combining coordinate transformation and geometric calculation. The first deviation is configured to compensate for the position of the rotation axis of the equipment, so that the rotation axis of the imaging equipment can run in an ideal horizontal position.

[0121] In an optional embodiment, for the second method of acquiring celestial images described above, the deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in an absolutely vertical position.

[0122] To calculate the aforementioned third deviation, in the process of obtaining the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations, the deviation analysis module 120 is specifically configured as follows:

[0123] Using the first celestial body image as a reference image, and obtaining the reference origin, acquire at least two sets of command position coordinates and actual position coordinates of the second celestial body image relative to the reference origin. Based on the command position coordinates and actual position coordinates of the at least two sets of second celestial body images, calculate the third deviation.

[0124] For example, the first set of coordinates is: commanded position coordinates (X1, Y1), actual position coordinates (X2, Y2); the second set of coordinates is: commanded position coordinates (W1, Z1), actual position coordinates (W2, Z2). Assuming that (X1, Y1) and (W1, Z1) are obtained under the same transformation law, or under the same deviation of the device's rotation axis, (X2, Y2) and (W2, Z2) can be calculated by quantifying such transformation law.

[0125] Optionally, based on the commanded position coordinates and actual position coordinates of at least two sets of celestial images, a transformation matrix is ​​calculated to transform the commanded position coordinates to the actual position coordinates; the inverse of the transformation matrix is ​​calculated to obtain the third deviation.

[0126] Suppose that (X1, Y1) and (W1, Z1) are obtained from (X2, Y2) and (W2, Z2) under the same transformation matrix, and assume that this matrix is... Substituting (X1, Y1) and (W1, Z1), (X2, Y2) and (W2, Z2) into the equation, we get:

[0127] Based on the above, the transformation matrix is ​​solved.

[0128] After obtaining the transformation matrix that can transform the commanded coordinate position into the actual coordinate position. Subsequently, this transformation matrix reflects the deviation between the actual and the ideal; since this embodiment requires calibration of the imaging device based on this transformation matrix, the inverse matrix of the transformation matrix is ​​further obtained. This is the third deviation in the embodiments of this disclosure, thereby enabling the generation of virtual command coordinates to eliminate the third deviation before actual imaging.

[0129] In an optional embodiment, when the deviation is a third deviation:

[0130] The deviation compensation unit 131 is configured to use a third deviation amount to compensate for the current position of the rotation axis and obtain virtual command coordinates. The device control unit 132 is specifically configured to control the imaging device to operate under the virtual command coordinates during the imaging process.

[0131] In the calibration process of imaging equipment, the role of the inverse matrix is ​​to transform the command coordinates of the imaging equipment's rotation axis (where its current position allows the equipment to capture an ideal image at that position) into virtual command coordinates assuming the imaging equipment's rotation axis is in an absolutely vertical position. This ensures that the image captured by the imaging equipment is at the position corresponding to these virtual command coordinates. For example, when it is necessary to transform the coordinates to (I2, J2) (the desired image position), this is done through... The (I2, J2) coordinates are processed to obtain the virtual command coordinates (I1, J1). The (I1, J1) instruction is sent to the device control unit 132 to control the imaging device to work under the virtual command coordinates (I1, J1), thereby achieving the goal of turning to the designated area.

[0132] Therefore, the calibration device 100 of the imaging device provided in this embodiment can calibrate the coordinates of the command position to be captured based on the third deviation (i.e., the inverse matrix of the transformation matrix) before each imaging, so that the imaging device can image at the virtual command coordinate position. This can effectively compensate for the imaging error caused by the deviation between the current position of the device's rotation axis and the absolute vertical position, thereby realizing the real-time calibration of the imaging device and ensuring the accuracy and stability of the imaging after calibration.

[0133] Please refer to Figure 3, which is a flowchart of the calibration process of the imaging device provided in this disclosure. This disclosure also provides an imaging device calibration method, which can be implemented by the electronic device shown in Figure 7. The imaging device calibration method includes the following steps:

[0134] Step S100: Based on at least three images of celestial bodies at different spatial locations, obtain the deviation between the current position and the ideal position of the rotation axis of the imaging device.

[0135] Step S200: Calibrate the imaging device based on the deviation.

[0136] In an optional embodiment, please refer to FIG4, which is a flowchart of a first calibration example provided by an embodiment of the present disclosure; wherein, the deviation includes a first deviation between the current position of the rotation axis and the absolute vertical position; the above step S200 is based on the deviation, and the calibration of the imaging device can be implemented in the following manner:

[0137] Step S211: Use the first deviation amount to compensate for the current position of the rotation axis and obtain the virtual horizontal position of the rotation axis.

[0138] Step S212: Control the theodolite to work in a virtual horizontal position.

[0139] In an optional embodiment, please refer to Figure 5, which is a flowchart of a second calibration example provided by an embodiment of this disclosure; wherein, the deviation includes a second deviation between the current position of the rotation axis and the position of the North Celestial Pole in the same coordinate system; the above step S200 is based on the deviation, and the calibration of the imaging device can be implemented in the following way:

[0140] Step S221: Use the second deviation to compensate for the current position of the rotation axis and obtain the virtual north pole position of the imaging device.

[0141] Step S222: Generate a device control signal including a second deviation and / or a virtual celestial position.

[0142] In an optional embodiment, please refer to Figure 6, which is a flowchart of a third calibration example provided by an embodiment of this disclosure; wherein, the deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in an absolutely vertical position. Step S200 described above is based on the deviation, and the imaging device can be calibrated in the following manner:

[0143] Step S231: Use the third deviation to compensate for the current position of the rotation axis and obtain the virtual command coordinates.

[0144] Step S232: During the imaging process of the imaging device, control the imaging device to work under virtual command coordinates.

[0145] In an optional embodiment, the different spatial locations include: a first spatial location and at least two second spatial locations. Step S100 above: Based on at least three celestial images from different spatial locations, the deviation between the current position and the ideal position of the imaging device's rotation axis can be obtained in the following way:

[0146] An imaging device that controls the rotation axis to acquire a first celestial body image in a first spatial position, and acquires at least two second celestial body images in at least two second spatial positions.

[0147] The first spatial position and the second spatial position include spatial positions at different azimuth angles under a preset elevation angle; or spatial positions at different elevation angles under a preset azimuth angle.

[0148] In an optional embodiment, the calibration method for the imaging device further includes:

[0149] The system monitors whether the level change of the virtual level of the imaging device operating in a virtual position exceeds a level change threshold. If the level change exceeds the threshold, a recalibration signal is generated.

[0150] In an optional embodiment, the calculation of the first deviation and the second deviation described above can be achieved in the following manner:

[0151] Based on three celestial images from different spatial locations, the coordinate positions of the three celestial images in the equatorial coordinate system are obtained respectively. The coordinate positions in the equatorial coordinate system are converted to coordinate positions in the rectangular coordinate system, and the normal vector of the plane formed by the three coordinate positions is calculated in the rectangular coordinate system. The normal vector in the rectangular coordinate system is converted to coordinate positions in the horizontal coordinate system to obtain the horizontal coordinates of the rotation axis. Based on the horizontal coordinates of the rotation axis and the standard horizontal coordinates of the rotation axis when it is in an absolutely vertical position, the deviation of the rotation axis is obtained.

[0152] In an optional embodiment, the calculation of the third deviation described above can be achieved in the following manner:

[0153] Using the first celestial body image as a reference image, a reference origin is obtained; at least two sets of command position coordinates and actual position coordinates of the second celestial body image relative to the reference origin are acquired; wherein, the command position coordinates represent the position coordinates of the second celestial body image acquired when the rotation axis of the imaging device is in an absolutely vertical position, and the actual position coordinates represent the coordinate positions of the second celestial body image acquired when the rotation axis of the imaging device is in the current position; based on the command position coordinates and actual position coordinates of at least two sets of second celestial body images, a third deviation is calculated.

[0154] This disclosure provides an imaging device, which includes an imaging module, a theodolite, and a controller.

[0155] The imaging module and the theodolite are connected to the controller.

[0156] The imaging module is configured to acquire at least three images of celestial bodies at different spatial locations and send the images to the controller.

[0157] The controller is configured to compensate for the current position of the rotation axis based on celestial images, obtain a virtual position, and send the virtual position to the theodolite.

[0158] The theodolite is configured to receive virtual locations.

[0159] The imaging device disclosed herein achieves rotation axis calibration based on celestial images through the coordinated operation of an imaging module, a theodolite, and a controller. The imaging module acquires celestial images from different spatial locations and sends them to the controller. The controller compensates for the current position of the rotation axis based on these images, calculates a virtual position, and sends this virtual position to the theodolite. Upon receiving the virtual position, the theodolite calibrates the imaging device. This imaging device effectively compensates for physical positional deviations of the device's rotation axis, ensuring precise alignment with the target and improving the device's positioning accuracy and imaging performance.

[0160] Please refer to Figure 7, which is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. An electronic device 200 provided in this embodiment includes: a processor 201 and a memory 202. The memory 202 stores machine-readable instructions executable by the processor 201. When the machine-readable instructions are executed by the processor 201, they perform steps in any implementation of the calibration method for the imaging device described above.

[0161] Based on the same disclosed concept, embodiments of this disclosure also provide a computer program product, which includes a computer program / instructions that are executed by a processor using steps in any implementation of the calibration method for the imaging device described above.

[0162] Based on the same disclosed concept, embodiments of this disclosure also provide a computer-readable storage medium storing computer program instructions, which, when read and executed by a processor, perform steps in any implementation of the calibration method for the imaging device described above.

[0163] The computer-readable storage medium can be any medium capable of storing program code, such as Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM).

[0164] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0165] The above description is merely an embodiment of this disclosure and is not intended to limit the scope of protection of this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure. Industrial applicability

[0166] By adopting the above solution, the autonomy of equipment calibration can be effectively improved. For users, the calibration process is greatly simplified, and the efficiency, accuracy and reliability of calibration are improved.

Claims

1. A calibration device for an imaging apparatus, characterized in that, The calibration device includes a deviation analysis module and a calibration module; The deviation analysis module is configured to obtain the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations. The calibration module is configured to calibrate the imaging device based on the deviation.

2. The calibration device according to claim 1, characterized in that, The different spatial locations include: a first spatial location and at least two second spatial locations; the calibration device also includes an image acquisition module; The image acquisition module is configured to control the imaging device to acquire a celestial body image at the first spatial position and to acquire at least two celestial body images at at least two second spatial positions.

3. The calibration device according to claim 2, characterized in that, The first spatial position and the second spatial position include spatial positions at different azimuth angles under a preset elevation angle; or spatial positions at different elevation angles under a preset azimuth angle.

4. The calibration apparatus according to any one of claims 1-3, characterized in that, The calibration module includes a deviation compensation unit and a device control unit; during the calibration of the imaging device based on the deviation amount: The deviation compensation unit is configured to use the deviation amount to compensate for the current position of the rotating axis to obtain a virtual position; The device control unit is configured to control the imaging device to operate based on the virtual location.

5. The calibration device according to claim 4, characterized in that, in, The deviation includes a first deviation between the current position of the rotation axis and its absolute vertical position, wherein the deviation is the first deviation: The deviation compensation unit is configured to use the first deviation amount to compensate for the current position of the rotation axis, thereby obtaining the virtual horizontal position of the imaging device; The device control unit is specifically configured to control the theodolite of the imaging device to operate at the virtual horizontal position.

6. The calibration apparatus according to claim 4 or 5, characterized in that, The calibration module further includes: a pseudo-level monitoring unit; The virtual level monitoring unit is configured to monitor whether the horizontal change of the virtual level of the imaging device operating at the virtual position exceeds a horizontal change threshold; and If the change in the virtual level exceeds the level change threshold, a recalibration signal is generated.

7. The calibration apparatus according to claim 6, characterized in that, in, The range of the horizontal change threshold includes [3°, 6°].

8. The calibration apparatus according to any one of claims 4-7, characterized in that, in, The deviation includes a second deviation between the current position of the rotation axis and the position of the North Celestial Pole in the same coordinate system, when the deviation is the second deviation. The deviation compensation unit is configured to use the second deviation amount to compensate for the current position of the rotation axis to obtain the virtual north pole position of the imaging device; The device control unit is configured to generate a device control signal that includes the second deviation amount and / or the virtual North Pole position.

9. The calibration apparatus according to any one of claims 1-8, characterized in that, In the process of obtaining the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations, the deviation analysis module is configured to: Based on the three celestial images from different spatial locations, the coordinate positions of the three celestial images in the equatorial coordinate system are obtained respectively; Convert the coordinate positions in the equatorial coordinate system to the coordinate positions in the rectangular coordinate system, and calculate the normal vector of the plane formed by the three coordinate positions in the rectangular coordinate system; The normal vector in the rectangular coordinate system is converted into the coordinate position in the horizontal coordinate system to obtain the horizontal coordinates of the rotation axis; The deviation of the rotation axis is obtained based on the horizontal coordinates of the rotation axis and the standard horizontal coordinates of the rotation axis when it is in an absolutely vertical position.

10. The calibration apparatus according to any one of claims 2-9, characterized in that, The deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its absolutely vertical position. In the process of obtaining the deviation between the current position and the ideal position of the imaging device's rotation axis based on at least three celestial images from different spatial locations, the deviation analysis module is specifically configured as follows: Using the first celestial body image as a reference image, a reference origin is obtained; At least two sets of commanded position coordinates and actual position coordinates of the second celestial body image relative to the reference origin are obtained; wherein, the commanded position coordinates represent the position coordinates of the second celestial body image obtained by the imaging device when the rotation axis is in an absolutely vertical position, and the actual position coordinates represent the coordinate position of the second celestial body image obtained by the imaging device when the rotation axis is in the current position; The third deviation is calculated based on the commanded position coordinates and actual position coordinates of at least two sets of the second celestial images.

11. The calibration apparatus according to claim 10, characterized in that, In the process of calculating the third deviation based on the commanded position coordinates and actual position coordinates of at least two sets of the second celestial images, the deviation analysis module is specifically configured as follows: Based on the commanded position coordinates and actual position coordinates of at least two sets of the second celestial images, calculate the transformation matrix from the commanded position coordinates to the actual position coordinates; Calculate the inverse of the transformation matrix to obtain the third deviation.

12. The calibration apparatus according to claim 10 or 11, characterized in that, When the deviation is the third deviation: The deviation compensation unit is configured to use the third deviation amount to compensate for the current position of the rotation axis and obtain virtual command coordinates; The device control unit is specifically configured to control the imaging device to operate under the virtual command coordinates during the imaging process of the imaging device.

13. A calibration method for an imaging device, characterized in that, The calibration method includes: Based on at least three images of the celestial body at different spatial locations, the deviation between the current position and the ideal position of the rotation axis of the imaging device is obtained; The imaging device is calibrated based on the deviation.

14. The calibration method according to claim 13, characterized in that, in, The deviation includes a first deviation between the current position of the rotation axis and its absolute vertical position; The calibration of the imaging device based on the deviation includes: Using the first deviation, the current position of the rotation axis is compensated to obtain the virtual horizontal position of the imaging device; Control the theodolite to operate at the virtual horizontal position.

15. The calibration method according to claim 13 or 14, characterized in that, in, The deviation includes a second deviation between the current position of the rotation axis and the position of the North Celestial Pole in the same coordinate system; the calibration of the imaging device based on the deviation includes: Using the second deviation, the current position of the rotation axis is compensated to obtain the virtual north pole position of the rotation axis; Generate a device control signal that includes the second deviation and / or the virtual north celestial pole position.

16. The calibration method according to any one of claims 13-15, characterized in that, in, The deviation includes a third deviation between the actual position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its current position and the commanded position coordinates of the celestial image acquired by the imaging device when the rotation axis is in its absolutely vertical position. The calibration of the imaging device based on the deviation includes: The third deviation is used to compensate for the current position of the rotation axis to obtain the virtual command coordinates; During the imaging process of the imaging device, the imaging device is controlled to operate under the virtual command coordinates.

17. An imaging device, characterized in that, The imaging device includes: an imaging module, a theodolite, and a controller; The imaging module and the theodolite are connected to the controller; The imaging module is configured to acquire at least three celestial images from different spatial locations and send the celestial images to the controller; The controller is configured to compensate for the current position of the rotation axis based on the celestial image, obtain a virtual position, and send the virtual position to the theodolite; The theodolite is configured to receive the virtual location.

18. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory storing program instructions, and the processor executing the program instructions to perform the steps of the method according to any one of claims 13-16.

19. A computer program product, characterized in that, The computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of the method according to any one of claims 13-16.

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