Photoelectric pod optical axis guide calibration method

Abstract

The invention relates to the technical field of airborne photoelectric pods, in particular to a photoelectric pod optical axis guide calibration method. Comprising the following steps: installing a photoelectric pod, and obtaining a reference point according to an angle value of the photoelectric pod; observing the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser, and adjusting the orientations of the visible light and infrared cameras; according to the focal length value range of the visible light lens and the infrared lens, the number of automatic axis calibration reference groups is calculated, and deviation calibration is carried out; the calibration parameters are stored, deviation is read from the calibration parameter file every time the photoelectric pod is started, and the center of the laser optical axis is indicated through the cross; in this way, the photoelectric pod optical axis calibration operation process is simplified, and the photoelectric pod optical axis calibration implementation cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of airborne optoelectronic pods, and particularly to an optoelectronic pod optical axis guiding and calibration method. Background Art

[0002] Existing optoelectronic pods usually have multiple imaging sensors such as visible light, long-wave infrared, mid-wave infrared, etc., as well as laser ranging and illuminating devices that are strongly correlated with positioning and guidance. Each component corresponds to an optical path. The optical axis of the optoelectronic pod is mostly based on the visible light or laser optical path, and the other components should be as consistent with the reference optical path as possible. The optical axis has a great influence on the functions of the optoelectronic pod such as positioning, guidance, and tracking channel switching. Especially for the positioning and guidance functions, it is a decisive factor for whether the stable platform type should be a pan-tilt or a pod. Therefore, the calibration of the optical axis is a very necessary task for the optoelectronic pod. Even if the machining accuracy of the optical bench and the mounting base is very high, there are still certain tolerances. Coupled with the influence of stress release and the error accumulation during the assembly process, it will ultimately lead to a large deviation of the optical axis. Optoelectronic pods are often used in vehicles such as unmanned aerial vehicles, helicopters, and ships with complex vibration conditions. Affected by the structural stress of the optical bench, the calibrated optical axis will shift to a certain extent during long-term operation, and the accumulated error will increase.

[0003] Currently, the optical axis calibration of optoelectronic pods mostly uses a collimator for measurement and calibration. The cost is expensive, and it requires a fixed professional site support and professional operators for operation and guarantee, which increases the complexity of the whole process. If it is an imaging component with a zoom lens, there will also be a certain deviation in the optical axis consistency. If the position of the laser is judged based on the image after zooming in or out by the zoom lens, it will introduce a systematic error.

[0004] Therefore, it is very necessary to propose an optoelectronic pod optical axis guiding and calibration method that simplifies the operation process of optoelectronic pod optical axis calibration and reduces the implementation cost of optoelectronic pod optical axis calibration. Summary of the Invention

[0005] The purpose of the present invention is to provide an optoelectronic pod optical axis guiding and calibration method, aiming to simplify the operation process of optoelectronic pod optical axis calibration and reduce the implementation cost of optoelectronic pod optical axis calibration.

[0006] To achieve the above purpose, an optoelectronic pod optical axis guiding and calibration method adopted by the present invention includes the following steps:

[0007] Install the optoelectronic pod, and obtain a reference reference point according to the angle value of the optoelectronic pod;

[0008] Observe the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser, and adjust the orientations of the visible light and infrared cameras;

[0009] Calculate the automatic alignment reference group numbers according to the visible light and infrared lens focal length value ranges respectively, and perform deviation calibration;

[0010] Save the alignment parameters. When the optoelectronic pod is started each time, read the deviation from the alignment parameter file and indicate the center of the laser optical axis through a cross.

[0011] Among them, in the step of obtaining the reference benchmark point according to the optoelectronic pod angle value during the installation of the optoelectronic pod:

[0012] Install the assembled frame of the optoelectronic pod on the optical experimental table by the window. Open the window to ensure that the laser can be normally emitted and received and the infrared detector can normally detect the target building, and connect the optoelectronic pod to the control computer with a network cable;

[0013] Power on the optoelectronic pod and use the control computer to control the optoelectronic pod screen to turn to the upper right corner of the target building;

[0014] Enable the laser emission, continuously fine-tune the optoelectronic pod. When one of the situations of invalid ranging value and increasing ranging value occurs, determine that the laser just hits the upper right corner of the target building, and record the current angle as the reference benchmark point.

[0015] Among them, in the step of enabling the laser emission, continuously fine-tuning the optoelectronic pod. When one of the situations of invalid ranging value and increasing ranging value occurs, determine that the laser just hits the upper right corner of the target building, and record the current angle as the reference benchmark point:

[0016] Turn on the laser ranging function of the optoelectronic pod, observe the ranging value in the picture, adjust the turning of the optoelectronic pod towards the upper right corner of the target building. When the optoelectronic pod turns to the right and the laser hits behind the target building, and one of the situations of invalid ranging value and increasing ranging value occurs, or when the optoelectronic pod turns upwards and the laser hits behind the target building, and one of the situations of invalid ranging value and increasing ranging value occurs, record the angle value of the optoelectronic pod at this moment, switch the mode of the optoelectronic pod to the follow-up frame angle mode of the current angle, and continuously fix this position as the reference benchmark point.

[0017] Among them, in the step of observing the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser and adjusting the orientations of the visible light and infrared cameras:

[0018] Respectively observe the pixel deviation values between the centers of the visible light and infrared pictures at the reference benchmark point and the target building, and calculate the installation errors of the visible light and infrared cameras on the optical bench according to the field of view angles of the imaging components and the deviation pixels in the pictures;

[0019] Power off the optoelectronic pod, and adjust the orientations of the visible light and infrared cameras on the optical bench according to the calculated installation deviations.

[0020] After powering off the optoelectronic pod and adjusting the orientations of the visible light and infrared cameras on the optical bench according to the calculated installation deviation:

[0021] Power on the optoelectronic pod and observe whether the deviation between the minimum fields of view of the visible light and infrared images and the actual position of the laser is within a half 64*64 pixel gate.

[0022] In the step of powering on the optoelectronic pod and observing whether the deviation between the minimum fields of view of the visible light and infrared images and the actual position of the laser is within a half 64*64 pixel gate:

[0023] If the deviation exceeds a half 64*64 pixel gate, continue to adjust the orientations of the visible light and infrared cameras on the optical bench.

[0024] In the step of calculating the automatic alignment reference groups respectively according to the focal length value ranges of the visible light and infrared lenses and performing deviation calibration:

[0025] Operate the computer to turn on the automatic alignment function of the optoelectronic pod and click on the upper right corner of the target building in the image, i.e., the actual position where the laser hits;

[0026] By means of image tracking, calculate in real time the deviation between the laser optical axis and the centers of the visible light and infrared images, calculate the appropriate calibration groups according to the range of the focal length values, pull the focal length to the positions of the calculated values accordingly to calibrate the deviation, and move the cross and the gate to the actual position of the laser optical axis.

[0027] An optoelectronic pod optical axis guidance and calibration method of the present invention obtains a reference reference point according to the optoelectronic pod angle value by installing the optoelectronic pod; observes the deviation between the minimum fields of view of the visible light and infrared images and the actual position of the laser and adjusts the orientations of the visible light and infrared cameras; calculates the automatic alignment reference groups respectively according to the focal length value ranges of the visible light and infrared lenses and performs deviation calibration; saves the alignment parameters, reads out the deviation from the alignment parameter file each time the optoelectronic pod is started, and indicates the center of the laser optical axis through the cross; simplifies the operation process of optoelectronic pod optical axis calibration and reduces the implementation cost of optoelectronic pod optical axis calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 is a step flow chart of the optoelectronic pod optical axis guidance and calibration method of the present invention.

[0030] Figure 2 is the flowchart of step S100 of the present invention.

[0031] Figure 3 is the flowchart of step S200 of the present invention.

[0032] Figure 4 is the flowchart of step S300 of the present invention.

[0033] Figure 5 is the schematic diagram of the implementation of the optical axis guidance calibration process of the optoelectronic pod of the present invention.

[0034] 1 - Optoelectronic pod, 2 - Frame, 3 - Control computer, 4 - Optical experiment table, 5 - Target building. Specific implementation manner

[0035] Here, exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present application.

[0036] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0037] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0038] Please refer to Figures 1 to 5 , the present invention provides an optoelectronic pod optical axis guidance calibration method, including the following steps:

[0039] S100: Install the optoelectronic pod 1, and obtain a reference benchmark point according to the angle value of the optoelectronic pod 1;

[0040] In this embodiment, a reference benchmark point is obtained according to the angle value of the optoelectronic pod 1; the specific process is as follows:

[0041] S101: Install the assembled frame 2 of the optoelectronic pod 1 on the optical experimental table 4 by the window. Open the window to ensure that the laser can be normally emitted and received and the infrared detector can normally detect the target building 5. Connect the network cable between the optoelectronic pod 1 and the control computer 3.

[0042] S102: Power on the optoelectronic pod 1 and use the control computer 3 to control the image of the optoelectronic pod 1 to turn to the upper right corner of the target building 5.

[0043] S103: Enable the laser emission and continuously fine-tune the optoelectronic pod 1. When one of the situations of invalid ranging value and increasing ranging value occurs, determine that the laser exactly hits the upper right corner of the target building 5, and record the current angle as the reference benchmark point.

[0044] In the above process, first install the assembled frame 2 of the optoelectronic pod 1 on the optical experimental table 4 by the window. Open the window to ensure that the laser can be normally emitted and received and the infrared detector can normally detect the target building 5. Connect the network cable between the optoelectronic pod 1 and the control computer 3 for observing the video and control. Then power on the optoelectronic pod 1 and use the control computer 3 to control the image of the optoelectronic pod 1 to turn to the vicinity of the upper right corner of the target building 5. Adjust the turning of the optoelectronic pod 1 towards the upper right corner of the target building 5. When the optoelectronic pod 1 turns to the right and the laser hits behind the target building 5, or when the optoelectronic pod 1 turns up and the laser hits behind the target building 5, and one of the situations of invalid ranging value and increasing ranging value occurs, record the angle value of the optoelectronic pod 1 at this moment. Switch the mode of the optoelectronic pod 1 to the follow-up frame 2 angle mode of the current angle, and continuously fix this position as the reference benchmark point.

[0045] S200: Observe the deviation between the minimum fields of view of the visible light and infrared images and the actual position of the laser, and adjust the orientations of the visible light and infrared cameras.

[0046] In this embodiment, observe the deviation between the minimum fields of view of the visible light and infrared images and the actual position of the laser, and adjust the orientations of the visible light and infrared cameras. The specific process is as follows:

[0047] S201: Observe the pixel deviation values between the centers of the visible light and infrared images at the reference benchmark point and the upper right corner of the target building 5 respectively, and calculate the installation errors of the visible light and infrared cameras on the optical bench according to the field of view angles of the imaging components and the pixel deviation of the images.

[0048] S202: Power off the optoelectronic pod 1 and adjust the orientations of the visible light and infrared cameras on the optical bench according to the calculated installation deviations.

[0049] S203: Power on the optoelectronic pod 1 and observe whether the deviations between the minimum fields of view of the visible light and infrared images and the actual position of the laser are within a half 64*64 pixel gate.

[0050] In the above process, first, observe the pixel deviation values between the centers of the visible light and infrared images at the reference reference point and the upper right corner of the target building 5 respectively. As Figure 5 shown in the laser optical path position, and calculate the installation errors of the visible light and infrared cameras on the optical bench according to the field of view angle of the imaging component and the deviation pixels in the image. Then, power off the optoelectronic pod 1. According to the calculated installation deviation, adjust the orientations of the visible light and infrared cameras on the optical bench by adding gaskets at the installation hole positions or other methods to reduce the installation deviation. Next, power on the optoelectronic pod 1 and observe whether the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser is within a half 64*64 pixel gate. If the deviation exceeds a half 64*64 pixel gate, continue to adjust the orientations of the visible light and infrared cameras on the optical bench.

[0051] S300: Calculate the automatic alignment reference groups respectively according to the visible light and infrared lens focal length value ranges, and perform deviation calibration;

[0052] In this embodiment, calculate the automatic alignment reference groups respectively according to the visible light and infrared lens focal length value ranges, and perform deviation calibration; the specific process is as follows:

[0053] S301: Turn on the automatic alignment function of the optoelectronic pod 1 through the control computer 3, and click on the upper right corner of the target building 5 in the image, that is, the position where the laser actually hits;

[0054] S302: By means of image tracking, calculate the deviation between the laser optical axis and the center of the visible light image in real time, calculate the appropriate calibration groups according to the range of the lens focal length value, pull the focal length to the calculated positions respectively to calibrate the deviation, and move the cross and the gate to the actual position of the laser optical axis.

[0055] In the above process, first, turn on the automatic alignment function of the optoelectronic pod 1 through the control computer 3, and click on the upper right corner of the target building 5 in the image, that is, the position where the laser actually hits. By means of image tracking, calculate the deviation between the laser optical axis and the center of the visible light image in real time, calculate the appropriate calibration groups according to the range of the lens focal length value, pull the focal length to the calculated positions respectively to calibrate the deviation, and move the cross and the gate to the actual position of the laser optical axis. The program automatically repeats the zooming and calibration operations; the automatic alignment program for the infrared processing process is the same as that for the visible light.

[0056] S400: Save the alignment parameters, and read the deviation from the alignment parameter file each time the optoelectronic pod 1 is started, and indicate the center of the laser optical axis through the cross.

[0057] In this embodiment, after calibration is exited, the axis calibration parameters are saved. Each time the optoelectronic pod 1 is started, the deviation is read from the axis calibration parameter file, and the center of the laser optical axis is indicated by a cross. After automatic axis calibration, when the optoelectronic pod 1 is tracking, the tracker will fuse the deviation information between the current component and the field of view angle with the miss distance, so that the image and the servo complete closed-loop linkage. At this moment, the laser will actually hit the tracked target, and the positioning accuracy of the optoelectronic pod 1 is improved.

[0058] Other embodiments of the present application will be readily apparent to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of the present application and include common general knowledge or conventional technical means in the technical field not disclosed herein.

[0059] It should be understood that the present application is not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A method for calibrating the optical axis of an optoelectronic pod, characterized in that: The steps include: Install the optoelectronic pod and obtain the reference point according to the optoelectronic pod angle value; Observe the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser, and adjust the direction of the visible light and infrared cameras; According to the focal length range of visible light and infrared lens, the number of reference groups for automatic axis calibration is calculated and deviation calibration is performed; Save the calibration parameters, read the deviation from the calibration parameter file each time the optoelectronic pod is started, and use the cross to indicate the center of the laser optical axis.

2. The method for calibrating the optical axis of an optoelectronic pod according to claim 1, characterized in that: When installing the optoelectronic pod, in the steps of obtaining the reference point according to the optoelectronic pod angle value: Install the assembled frame of the optoelectronic pod on the optical laboratory table by the window, open the window to ensure that the laser can be transmitted and received normally and the infrared detector can detect the target building normally, and connect the optoelectronic pod to the control computer through the network cable; Power on the optoelectronic pod and use the control computer to turn the optoelectronic pod screen to the upper right corner of the target building; Enable laser emission and continue to fine-tune the optoelectronic pod. When the ranging value becomes invalid or increases, make sure that the laser hits the upper right corner of the target building and record the current angle as the reference point.

3. The method for calibrating the optical axis of an optoelectronic pod according to claim 2, characterized in that: When the laser emission is enabled and the optoelectronic pod is continuously fine-tuned, and the ranging value is invalid or increases, in the steps of determining that the laser is hitting the upper right corner of the target building and recording the current angle as the reference point: Turn on the laser ranging function of the optoelectronic pod, observe the ranging value in the screen, adjust the steering of the optoelectronic pod, aim at the upper right corner of the target building, and make the optoelectronic pod turn right. The laser hits the back of the target building, and the ranging value becomes invalid or increases. The optoelectronic pod turns upward, and the laser hits the back of the target building. The ranging value becomes invalid or increases. Record the angle value of the optoelectronic pod at this moment, switch the mode of the optoelectronic pod to the follow-up frame angle mode of the current angle, and continue to fix this position as the reference reference point.

4. The method for calibrating the optical axis of an optoelectronic pod according to claim 1, characterized in that: In the steps of observing the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser, and adjusting the direction of the visible light and infrared cameras: Observe the pixel deviation values ​​between the center of the visible light and infrared images and the upper right corner of the target building at the reference point, and calculate the installation errors of the visible light and infrared cameras on the optical bench according to the field of view of the imaging component and the image deviation pixels; Turn off the power of the optoelectronic pod and adjust the orientation of the visible light and infrared cameras on the optical bench according to the calculated installation deviation.

5. The method for calibrating the optical axis of an optoelectronic pod according to claim 4, characterized in that: After the optoelectronic pod is powered off and the orientation of the visible light and infrared cameras on the optical bench is adjusted according to the calculated installation deviation: Power on the optoelectronic pod and observe whether the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser is within half a 64*64 pixel wave gate.

6. The method for calibrating the optical axis of an optoelectronic pod according to claim 5, characterized in that: When the optoelectronic pod is powered on, the steps of observing whether the deviation between the minimum field of view of the visible light and infrared images and the actual position of the laser is within half of the wave gate of 64*64 pixels are: If the deviation exceeds half of the 64*64 pixel wave gate, continue to adjust the orientation of the visible light and infrared cameras on the optical bench.

7. The method for calibrating the optical axis of an optoelectronic pod according to claim 1, characterized in that: In the steps of calculating the number of reference groups for automatic axis calibration according to the focal length ranges of visible light and infrared lenses, and performing deviation calibration: Turn on the automatic axis calibration function of the optoelectronic pod by controlling the computer, and click on the upper right corner of the target building in the picture, which is the actual position where the laser hits; Through the image tracking method, the deviation between the laser optical axis and the center of the visible light and infrared image is calculated in real time. According to the range of the lens focal length value, the appropriate number of calibration groups is calculated to pull the focal length to the calculated value position, calibrate the deviation, and move the cross and wave gate to the actual position of the laser optical axis.

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