4pi full-sphere space target display and tracking observation simulation device

Abstract

The application relates to a 4PI full-sky space target display and tracking observation simulation device, and relates to the technical field of space optical tracking and measurement. The device solves the problems of insufficient field of view, low precision and poor dynamic performance of a traditional dynamic space target simulator. In the test, a 4PI full-sky star field scene and a space dynamic target are simulated and generated on a full-sky target display device, the process of actively discovering a space target and tracking observation of an optical monitoring satellite in orbit is simulated, a spaceborne optical load images the star field scene on the full-sky space target display, space targets are detected and angle measurement is carried out through image processing, and the motion attitude of a to-be-measured optical load is adjusted according to the motion track of the space target, so that the space target is monitored and tracked. The application simulates the whole process from the discovery of the space target to the continuous tracking of the optical monitoring satellite in orbit, analyzes and evaluates the target tracking performance of the optical load.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of space optical tracking and measurement, in particular to a 4Π full-sky space target display and tracking observation simulation device. BACKGROUND

[0002] The space target simulation device is a device for testing the function of a space target optical monitoring system, which is usually combined with a measured optical load and a host computer to form a closed-loop test system, and can simulate a star field scene and a space target in real time. The working principle of the space target simulation device is as follows: according to the attitude angle and the orbit position of a star given by a simulation computer, the direction of the optical load optical axis is calculated through coordinate transformation, and a star field scene and a space target in the field of view are simulated and generated. Since the space target to be observed can be located in any direction of the in-orbit optical monitoring satellite, i.e. in the direction of the full-sky 4Π solid angle, a simulation system that can simulate and display space targets in the full-sky 4Π needs to be constructed to simulate the entire process from the discovery of a space target to the continuous tracking of the in-orbit optical monitoring satellite. In addition, since high-dynamic targets such as satellites, spaceships and space debris move very fast in the field of view, they will soon leave the observation field of view, so the satellite platform needs to actively adjust the attitude to complete the observation and tracking of the space target. In summary, in the research of space target optical monitoring technology, a full-sky space target display and tracking observation simulation device with a large field of view, high precision and high dynamics is needed.

[0003] The current space target simulator mainly projects a display device to the entrance pupil of the optical load through a collimation system to simulate a space target. Due to the limitation of the field of view angle of the collimation optical system, the maximum field of view angle is only about 40°, so it is difficult to simulate high-speed moving space targets. In addition, the simulation accuracy of the existing space target simulator is limited by the resolution of the display device, and it is difficult to achieve high-precision simulation of space targets. The collimation optical system also introduces optical aberrations such as distortion and field curvature, further reducing the simulation accuracy of the space target. The above problems are increasingly unable to meet the requirements of real-time simulation of full-sky space targets. In recent years, research at home and abroad has mainly focused on improving the field of view angle and the simulation accuracy of space targets of the simulator. Space target simulators are only found in the research of star sensors, and there is a lack of simulation devices and experimental environments specifically for 4Π full-sky space targets, which cannot provide effective guidance for the research of space target optical monitoring technology. SUMMARY

[0004] The present application provides a 4Π full-sky space target display and tracking observation simulation device to solve the problems of insufficient field of view, low precision and poor dynamic performance of traditional dynamic space target simulators.

[0005] To solve the above technical problems, the technical scheme of the present application is as follows:

[0006] A 4Π full-sky space target display and tracking observation simulation device, comprising: a full-sky space target display, a video signal processor, a network control switch, a three-axis air floatation high-precision rotating table, an optical load to be tested, a starry sky simulation computer, an image processing computer and a dynamics simulation computer;

[0007] The full-sky space target display is composed of a spherical LED display panel;

[0008] The optical load to be tested is fixed on the three-axis air floatation high-precision rotating table,

[0009] The starry sky scene and the space dynamic target are generated by the full-sky space target display, and the starry sky scene and the space dynamic target generated by the full-sky space target display are imaged by the optical load to be tested and then transmitted to the image processing computer;

[0010] The image processing computer extracts the motion parameters of the space dynamic target through the identification and tracking algorithm of the space dynamic target for the received image, obtains the azimuth information of the space dynamic target through calculation and analysis, and transmits the azimuth information to the dynamics simulation computer;

[0011] The dynamics simulation computer adopts a corresponding control strategy according to the relative angle change of the space dynamic target, and transmits the control instruction to the three-axis air floatation high-precision rotating table and the starry sky simulation computer;

[0012] After receiving the control instruction, the three-axis air floatation high-precision rotating table changes the attitude angle of the optical load to be tested through the control of the three-axis air floatation high-precision rotating table, so that the optical load to be tested is always aligned with the space dynamic target on the full-sky space target display, and the tracking observation of the space dynamic target by the optical load to be tested is completed;

[0013] The starry sky simulation computer receives the satellite position, velocity and attitude information transmitted by the dynamics simulation computer, and then simulates the generation of the space dynamic target and the real-time starry sky scene in the viewing area of the optical load to be tested according to the predetermined parameters and transmits them to the video signal processor;

[0014] The video signal processor performs fusion processing on the received space dynamic target and real-time starry sky scene image, generates a full-sky video image, and transmits the full-sky video image to the network control switch;

[0015] The network control switch decomposes the full-sky video image and transmits it to each LED display panel of the full-sky space target display, and each LED display panel synchronously refreshes the scene at the same refresh rate.

[0016] The beneficial effects of the present application are:

[0017] The 4Π full-sky space target display and tracking observation simulation device of the present application. During testing, the 4Π full-sky starry sky scene and space dynamic target are simulated on the full-sky target display device, simulating the process of active discovery and tracking observation of space targets by the optical monitoring satellite in orbit. The spaceborne optical load images the starry sky scene on the full-sky space target display, detects and measures the angle of the space target through image processing, and adjusts the motion attitude of the optical load to be tested according to the motion trajectory of the space target, realizing the monitoring and tracking of the space target.

[0018] In the present application, the spherical surface spliced LED display panel is used to realize the simulation of full-sky space targets and starry sky scenes, simulate the monitoring and tracking process of space dynamic targets by the satellite in the actual in-orbit scene. Finally, through computer processing, the target tracking algorithm performance of the optical load to be tested is specifically analyzed and evaluated. The experimental device has very important guiding significance for the research of space target optical monitoring technology. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0020] Figure 2 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0021] Figure 3 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0022] Figure 4 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0023] Figure 5 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0024] Figure 6 Fig. 1 is a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device of the present application;

[0025] In the figure: 1, full-sky space target display, 2, video signal processor, 3, network control switch, 4, three-axis air floatation high-precision rotary table mounting support frame, 5, optical load to be tested, 6, starry sky simulation computer, 7, image processing computer, 8, dynamic simulation computer. DETAILED DESCRIPTION

[0026] The following embodiments given in conjunction with the drawings further describe the simulation device of the present application.

[0027] As Figure 1As shown, a schematic diagram of a 4Π full-sky space target display and tracking observation simulation device. A 4Π full-sky space target display and tracking observation simulation device, comprising: a full-sky space target display 1, a video signal processor 2, a network control switch 3, a three-axis air floatation high-precision rotating table, a rotating table mounting support frame 4, an optical load to be tested 5, a starry sky simulation computer 6, an image processing computer 7, and a dynamics simulation computer 8.

[0028] An external aluminum alloy rotating table support frame is installed on a horizontal platform;

[0029] The dynamics simulation computer 8 sends attitude adjustment instructions to the three-axis air floatation high-precision rotating table;

[0030] The optical load to be tested 5 is fixed on the three-axis air floatation high-precision rotating table, and changes attitude according to the corresponding attitude adjustment instructions to simulate the attitude adjustment process during satellite flight in orbit.

[0031] The optical load to be tested 5 images the simulated dynamic optical target on the focal plane of the camera, and after receiving the video signal through the photosensitive element, transmits the video signal to the image processing computer 7.

[0032] The image processing computer 7 is used to process the images collected by the optical load to be tested, identifies and tracks the space dynamic target, extracts the motion parameters of the space dynamic target, calculates and analyzes the accurate position of the target, and sends it to the dynamics simulation computer.

[0033] The starry sky simulation computer 6 is responsible for receiving the satellite position, velocity and attitude information transmitted by the dynamics simulation computer, as well as the position and velocity information of the space dynamic target, and simulating the starry sky scene in the area viewed by the optical load to be tested carried by the satellite.

[0034] The video signal processor 2 performs splicing and fusion processing on the video signal output by the starry sky simulation computer, forms a whole full-sky starry sky scene and space dynamic target image, and transmits it to the network control switch through HDMI signal.

[0035] The network switch 3 decomposes the whole full-sky space target and starry sky scene picture, transmits it to each LED display control unit through CAT6 network cable, and synchronously refreshes the scene according to the specific refresh rate of the system.

[0036] In the simulation device described in this embodiment, the image processing computer 7 and the dynamics simulation computer 8 are connected by a data transmission line; the dynamics simulation computer 8 and the star simulation computer 6 are connected by a data transmission line; the star simulation computer 6 and the video signal processor 2 are connected by a video signal line; the video signal processor 2 and the network control switch 3 are connected by an HDMI signal line; the individual LED control units of the spherical display that make up the complete sphere are connected to the network control switch by a CAT6 network cable; the image processing computer and the optical payload to be tested are connected by a video signal transceiver and a PCI image acquisition card; the dynamics simulation computer and the three-axis air-bearing high-precision rotary table are connected by a wireless transceiver for receiving attitude adjustment commands.

[0037] Detailed Working Principle: Before conducting the simulation experiment, the internal parameters and distortion coefficients of the optical payload under test need to be determined using a pinhole model calibration algorithm. During testing, the optical payload under test is fixed on a three-axis air-bearing high-precision rotary table, and the air bearings are opened to simulate the microgravity and micro-friction conditions of a satellite in orbit. The simulation system is run, and a starry sky scene and space targets are generated on the all-sky target display device. The optical payload under test images the starry sky scene on the all-sky space target display and transmits it wirelessly to an image processing computer. The image processing computer corrects the image based on the distortion coefficients before the experiment, uses a moving target recognition algorithm to detect the space targets, and calculates the azimuth information of the space targets. This information is then sent to a dynamic simulation computer, which, based on the relative angle change of the space moving targets, adopts corresponding control strategies and sends attitude adjustment commands to the three-axis air-bearing high-precision rotary table via a wireless transceiver. After receiving the control commands, the rotary table changes the attitude angle of the optical payload under test through the control mechanism, ensuring that it is always aligned with the space moving targets, thereby completing the tracking and observation of the dynamic space targets by the optical payload under test.

[0038] like Figure 2 The diagram shown is a flowchart of the operation of a 4Π all-sky space target display and tracking observation simulation device according to this embodiment, which specifically includes the following:

[0039] The all-sky space target display provides the optical payload under test with a star map scene and dynamic space targets, and then the spaceborne optical payload images the all-sky target display.

[0040] The image processing computer 7 performs distortion correction on the image, detects spatial targets, and obtains the orientation information of the spatial targets;

[0041] The dynamics simulation computer 8 sends the relative angle change of the space target to the three-axis air-bearing high-precision rotary table and the star simulation computer.

[0042] The star simulation computer 6 is responsible for receiving satellite position, velocity and attitude information transmitted by the dynamics simulation computer, and then simulating and generating dynamic space targets and real-time star scenes according to preset parameters;

[0043] The video signal processor fuses the target and scene images to generate a full-sky video image;

[0044] The network control switch 3 breaks down the entire celestial globe image and transmits it to the control unit of each LED display panel;

[0045] The three-axis air-bearing high-precision rotary table receives an attitude adjustment command and controls the rotary table mechanism to change the attitude angle of the optical load to be measured, so that it is always aligned with the target moving in space.

[0046] Figure 3 This is a data flow diagram representing a device for displaying all-sky space targets and simulating starry sky scenes.

[0047] The network switch breaks down the entire celestial target and starry sky scene into individual images and transmits them to each LED display control unit via CAT6 network cables, while simultaneously refreshing the scene according to the frame rate set by the system.

[0048] The star simulation computer 6 is connected to the video signal processor 2 to receive monitoring satellite data and space target data;

[0049] The video signal processor 2 performs position calculations on the corresponding moving objects in the scene based on the received scene driving data, including: calculation of the satellite's on-orbit position (based on monitoring satellite data), calculation of the position of the space target (based on space target data), and calculation of the position of the sun and moon (based on the timestamp of the monitoring satellite); after processing the data sent by the deep space simulation computer, the video signal processor outputs it to the network control switch through the HDMI video interface. Figure 4 A simulation of a starry sky scene and dynamic spatial targets generated for a video signal processor.

[0050] like Figure 5 As shown, Figure 5 This simulation establishes the relationship between the coordinate system of the optical payload under test, the coordinate system of the all-sky space target display, the target orientation, and its screen projection position. After determining the orientation of the space target's centroid coordinates within the optical payload coordinate system, the accurate position of the dynamic space target on the display screen can be obtained through view transformation. Because in the optical payload coordinate system O... c In -xyz, the x-axis represents the direction of the optical payload's line of sight center, while according to the definition of view coordinates, the screen coordinate S... x The axis is horizontal to the right. Because the viewpoint can be defined using the same scale as the physical scale of the hardware device, there is only a rotational transformation relationship between the optical load coordinates and the screen coordinates, without any scale difference.Figure 5 It can be seen that the yz plane of the screen coordinate and the optical load field coordinate is parallel, the distance from the optical load to the screen is d, and the extension line of the vector in the optical load coordinate and the screen coordinate is the point of x = d on the straight line. The corresponding relationship between the screen coordinate and the optical load field coordinate is:

[0051] S x = -y; S y = z

[0052] where S x is the X axis of the screen coordinate, and S y is the Y axis of the screen coordinate.

[0053] Suppose that the vector in the optical load field coordinate system is It can be expressed as:

[0054]

[0055] where m, n, and l are the projection lengths in the three-axis coordinate system.

[0056] Then the equation of the straight line derived from the vector is:

[0057]

[0058] The intersection point of the straight line and the screen is:

[0059] x = d;

[0060] Therefore, the projection coordinate of the target point on the screen relative to the optical load field coordinate direction is a unit vector .

[0061]

[0062] After the screen coordinate of the target point is calculated, it can be judged whether the target point projection is in the screen according to the physical size of the screen, and the target point is drawn at the corresponding position.

[0063] The application will be described in detail in combination with examples as follows:

[0064] As shown in the drawings, Figure 6 is a structural schematic view of a full-sky space target display and tracking observation simulation device. Figure 6

[0065] ​​The full-sky space target display is composed of five different size specifications of LED panels. Each LED panel corresponds to a region of 20 degrees of longitude and 20 degrees of latitude on the sphere. The full-sky can be divided into 18 spherical surfaces according to 20 degrees of longitude, and then divided into 8 regions according to 20 degrees of latitude. Due to the symmetry of the full-sky, the LED panels of the northern and southern hemispheres can be interchanged.

[0066] Figure 6 In the figure, ①, ②, ③, ④ and ⑤ represent five specifications of LED display panels that make up the full-sky space target display. ①, ②, ③ and ④ constitute different latitude display regions on the full-sky space target display, and ⑤ constitutes the display region of the north and south poles on the full-sky space target display. ① is the LED display panel corresponding to the spherical display region of 0°-20°N and 0°-20°S; ② is the LED display panel corresponding to the spherical display region of 20°-40°N and 20°-40°S; ③ is the LED display panel corresponding to the spherical display region of 40°-60°N and 40°-60°S; ④ is the LED display panel corresponding to the spherical display region of 60°-80°N and 60°-80°S; the corresponding longitude range of ①, ②, ③ and ④ is 20°, and the 18 groups of display panels are connected end to end to constitute a complete 360° circumference; ⑤ is the LED display panel corresponding to the spherical display region of 80°N-90°N and 80°S-90°S; the full-sky space target display device uses 36 LED display panels of specifications ①, ②, ③ and ④ respectively, and 2 LED panels of region ⑤, for a total of 146 panels.

[0067] This embodiment uses spherical spliced LED display panels to realize full-sky space target and starry sky scene simulation, simulate the monitoring and tracking process of space dynamic targets under the true in-orbit scene of satellites, and through computer processing, specifically analyze and evaluate the target tracking algorithm performance of the optical load to be tested. The experimental device has very important guiding significance for the research of space target optical monitoring technology.

[0068] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0069] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A 4Π full-sky space target display and tracking observation simulation device, comprising a full-sky space target display, a video signal processor, a network control switch, a three-axis air floating high-precision rotating table, an optical load to be tested, a starry sky simulation computer, an image processing computer and a dynamics simulation computer; characterized in that: the full-sky space target display is composed of a spherical LED display panel; the optical load to be tested is fixed on the three-axis air floating high-precision rotating table; a starry sky scene and a space dynamic target are generated by the full-sky space target display, and the starry sky scene and the space dynamic target generated by the full-sky space target display are imaged by the optical load to be tested and then transmitted to the image processing computer; the image processing computer extracts the motion parameters of the space dynamic target through the identification and tracking algorithm of the space dynamic target, obtains the azimuth information of the space dynamic target through calculation and analysis, and transmits the azimuth information to the dynamics simulation computer; the dynamics simulation computer adopts a corresponding control strategy according to the relative angle change of the space dynamic target, and transmits the control instruction to the three-axis air floating high-precision rotating table and the starry sky simulation computer; the three-axis air floating high-precision rotating table receives the control instruction, changes the attitude angle of the optical load to be tested by controlling the three-axis air floating high-precision rotating table, so that the optical load to be tested always points to the space dynamic target on the full-sky space target display, and the tracking observation of the space dynamic target by the optical load to be tested is completed; the starry sky simulation computer receives the satellite position, velocity and attitude information transmitted by the dynamics simulation computer, then simulates the space dynamic target and the real-time starry sky scene in the viewing area of the optical load to be tested according to the predetermined parameters, and transmits the space dynamic target and the real-time starry sky scene to the video signal processor; the video signal processor performs fusion processing on the received space dynamic target and real-time starry sky scene images, generates a full-sky video image, and transmits the full-sky video image to the network control switch; the network control switch decomposes the full-sky video image and transmits it to each LED display panel of the full-sky space target display, and each LED display panel synchronously refreshes the scene at the same refresh rate. The video signal processor calculates the position of the space dynamic target in the starry sky scene according to the received space dynamic target and real-time starry sky scene images, including the calculation of the satellite position in orbit, the calculation of the space target position and the calculation of the sun and moon position; after the video signal processor processes the data sent by the starry sky simulation computer, the data is transmitted to the network control switch through the HDMI video interface. Further comprising a rotating table mounting support frame, and the three-axis air floating high-precision rotating table is mounted on the rotating table mounting support frame.

4. The 4Π full-sky space target display and tracking observation simulation device according to claim 1, characterized in that: ​ ​ ​ ​ ​ ​ 2. The 4Π all-sky space object display and tracking observation simulation device according to claim 1, characterized in that: ​ 3. The 4Π all-sky space object display and tracking observation simulation device according to claim 1, characterized in that: ​ ​ The image processing computer and the dynamics simulation computer are connected by a data transmission line; the dynamics simulation computer and the starry sky simulation computer are connected by a data transmission line; the starry sky simulation computer and the video signal processor are connected by a video signal line; the video signal processor and the network control switch are connected by an HDMI signal line.

5. The 4Π all-sky space object display and tracking observation simulation device according to claim 1, characterized in that: The single LED control unit in the full-sky space target display and the network control switch are connected by a CAT6 network cable; the image processing computer and the optical load to be tested are connected by a video signal transceiver and a PCI image acquisition card; the dynamics simulation computer and the three-axis air floating high-precision rotating table are connected by a wireless transceiver for receiving attitude adjustment instructions.

6. The 4Π all-sky space object display and tracking observation simulation device according to claim 1, characterized in that: The method for simulation by using the simulation device is as follows: Step one, providing a star map scene and a space dynamic target for the optical load to be tested by the full-sky space target display, and then imaging the full-sky target display by the spaceborne optical load; Step two, imaging the full-sky target display by the spaceborne optical load, correcting the image by the image processing computer, detecting the space target, and obtaining the azimuth information of the space target; Step three, sending the relative angle change of the space target to the three-axis air floating high-precision rotating table and the starry sky simulation computer by the dynamics simulation computer; The starry sky simulation computer is responsible for receiving the satellite position, speed and attitude information transmitted by the dynamics simulation computer, and then simulating and generating the space dynamic target and the real-time starry sky scene according to the preset parameters; The video signal processor performs fusion processing on the target and scene pictures to generate a full-sky video image; The network control switch decomposes the full-sky picture and transmits it to the control unit of each LED display panel; Step four, receiving the attitude adjustment instruction by the three-axis air floating high-precision rotating table, controlling the rotating table mechanism to change the attitude angle of the optical load to be tested, and always aiming at the space moving target.

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