Dynamic flight target infrared simulation method and system

Abstract

The invention relates to the technical field of target simulation, in particular to a dynamic flight target infrared simulation method and system, and the method comprises the steps: firstly calculating a target three-dimensional temperature field, and then generating infrared radiation characteristic diagrams of different attitudes through the rendering of the data of the three-dimensional temperature field, so as to construct a target infrared characteristic diagram data set; during simulation, according to simulation data, the infrared radiation characteristic diagram number of the target under the corresponding attitude is solved, and target imaging parameters are calculated; calling a posture infrared radiation characteristic diagram corresponding to the target by using the number, adjusting the target image according to the target imaging parameter, and fusing the target image with the background to generate an infrared scene diagram; and finally, converting the scene graph into a thermal radiation signal through an infrared target simulator, and simulating a relative visual angle of the target and the aircraft by using a five-axis simulation turntable to realize dynamic target relative motion simulation detection semi-physical simulation. The method solves the problems of poor real-time performance and low fidelity of infrared target simulation in the prior art, and has the advantages of high simulation efficiency and good fidelity.

Description

Technical Field

[0001] The present application relates to the technical field of target simulation, and in particular to a method and system for infrared simulation of dynamic flying targets. Background Art

[0002] With the continuous development of optical infrared imaging detection technology, infrared detection methods have demonstrated significant advantages in the detection, identification, and tracking of civilian and military targets, becoming a key technology in modern optical detection systems. Infrared target scene generation and simulation are widely used in flight simulator design, target detection and identification algorithm development, and infrared imaging guidance system development. However, generating high-fidelity infrared images of targets is difficult and costly, especially for high-speed dynamic targets, which are particularly challenging and rely heavily on simulation.

[0003] Existing infrared target scene generation and simulation solutions primarily include full mathematical simulation and image simulation based on existing data. Full mathematical simulation utilizes target radiation characteristics, atmospheric and environmental radiation characteristics, atmospheric transmission of infrared radiation, and the imaging mechanism of imaging equipment to simulate infrared images. However, full mathematical simulation methods struggle to meet the demands of real-time dynamic simulation, require high modeling fidelity, and are computationally time-consuming. Image simulation based on existing data, on the other hand, primarily assigns material properties (thermal properties, optical parameters, spectral characteristics, etc.) to the target and background, combining physical effect modeling to recreate the infrared imaging process. This approach can generate infrared images of large, complex scenes (such as Digital Earth-level scenes). However, its reliance on material partitioning and frame rate requirements results in insufficient modeling accuracy of target thermal infrared characteristics and inadequate analysis of heat source impacts, impacting the accuracy of target infrared signatures and the reliability of software and hardware verification.

[0004] Hardware-in-the-loop simulation can replace physical tests with repeated experimental research at a lower cost and higher execution rate through theoretical analysis, ground tests and selected physical tests, and obtain complete experimental data of the system under various states. Therefore, hardware-in-the-loop simulation has been applied to various fields with its unique functions and outstanding advantages.

[0005] For example, the invention patent application with publication number CN102538598A discloses a motion simulation system for infrared targets, which provides target simulators with different target energies, and drives the target simulators to perform individual or compound movements on the horizontal and pitch planes, and a positioning fixture that supports the guidance cabin. The industrial computer then completes the human-computer interaction and sends the processed control signal to the motion control system. The motion control system receives the control signal sent by the host computer, further processes the control signal, and sends it to the execution component.

[0006] However, the above simulation system has a simple structure and limited simulation dimension. The detection and guidance head is fixedly placed to aim at the target simulator. There is no attitude simulation and it is only suitable for the simulation of simple dynamic scenes. Summary of the Invention

[0007] The purpose of the present invention is to provide a dynamic flying target infrared simulation method and system, which partially solves or alleviates the above-mentioned deficiencies in the prior art, can meet the real-time simulation requirements, and also generate infrared target characteristic images with high fidelity, significantly improving the simulation efficiency and accuracy.

[0008] In order to solve the above-mentioned technical problems, the present invention specifically adopts the following technical solutions: A first aspect of the present invention is to provide a method for infrared simulation of a dynamic flying target, comprising the following steps: Using fluid simulation software to calculate the three-dimensional temperature field data of the simulated target, quantizing and rendering the three-dimensional temperature field data to obtain the target infrared radiation characteristic map, and collecting and numbering the corresponding target infrared radiation characteristic maps by controlling the posture changes of the simulated target, thereby forming a target infrared characteristic map data set; During simulation, a real-time simulator is used to calculate and output the pose data of the simulated target and the aircraft in real time, a relative viewing angle is calculated based on the pose data of the simulated target and the aircraft, and the number of the corresponding target infrared radiation characteristic diagram is solved using the relative viewing angle; Calculating the coordinates of the head and tail vertices of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, converting the coordinates of the head and tail vertices into a pixel coordinate system based on a preset camera imaging model, and calculating target imaging parameters, wherein the target imaging parameters include pixel size, imaging position, and pointing angle; Based on the number of the calculated target infrared radiation characteristic map, the target infrared radiation characteristic map of the corresponding posture is read from the target infrared characteristic map data set, and the target size and direction of the target infrared radiation characteristic map are adjusted according to the target imaging parameters to obtain an adjusted target infrared image, and then the scene background image is read, and the adjusted target infrared image is pasted into the background image according to the calculated target imaging position to form a scene image with the target infrared characteristics; The scene graph with the target infrared characteristics is output to the infrared dynamic target simulator in real time at a fixed frequency. The infrared dynamic target simulator converts the image data into a realistic infrared thermal radiation signal, and uses a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft. Then, the motion control of the five-axis simulation turntable is used to realize the semi-physical simulation of the relative motion simulation detection of the dynamic target.

[0009] Furthermore, the quantifying and rendering the three-dimensional temperature field data to obtain a target infrared radiation characteristic diagram includes: The radiation brightness of the temperature value of each point in the three-dimensional temperature field data is calculated and quantized to a range of 0-255 to form the thermal radiation grayscale value of the simulated target, and the target infrared radiation characteristic map is obtained by rendering.

[0010] Furthermore, the collecting and numbering of corresponding target infrared radiation characteristic diagrams by controlling the posture change of the simulated target includes: By controlling the roll angle of the simulated target around the X-axis from 0 to 360 degrees, with an interval of N degrees, and adjusting the yaw angle around the Y-axis from 0 to 180 degrees, with an interval of N degrees, the target infrared radiation characteristic maps of the simulated target in different postures are collected and numbered according to the posture angle information to form a target infrared characteristic map dataset.

[0011] Furthermore, the collecting and numbering of corresponding target infrared radiation characteristic diagrams by controlling the posture change of the simulated target includes: The roll angle or relative viewing angle of the simulated target is used as the first digit of the number, the relative viewing angle or roll angle between the simulated target and the aircraft is used as the second digit of the number, and the first digit and the second digit are separated by a short line.

[0012] Furthermore, the step of calculating the relative viewing angle based on the pose data of the simulated target and the aircraft, and using the relative viewing angle to calculate the number of the corresponding target infrared radiation characteristic diagram includes: The position of the aircraft is converted to the coordinate system of the simulated target, the unit vector of the aircraft in the target coordinate system is obtained, and the angle between the unit vector of the aircraft in the target coordinate system and the unit vector of the X-axis of the simulated target is calculated. The angle is used as the relative viewing angle and combined with the roll angle of the simulated target itself to solve the corresponding target infrared radiation characteristic diagram number.

[0013] Furthermore, the step of calculating the head and tail vertex coordinates of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, and converting the head and tail vertex coordinates into a pixel coordinate system based on a preset camera imaging model includes: The real-time simulation machine calculates and outputs the pose data of the simulated target and the aircraft in real time as spatial three-dimensional coordinate points in the geodetic coordinate system. According to the pose of the preset camera imaging model in the geodetic coordinate system, the transformation matrix between the camera coordinate system and the geodetic coordinate system is calculated, and the head and tail vertices of the simulated target in the geodetic coordinate system are converted to the camera coordinate system. Then, the pixel coordinate points of the simulated target in the two-dimensional image are calculated according to the three-dimensional coordinate points of the head and tail of the simulated target in the camera coordinate system.

[0014] Furthermore, the calculation of target imaging parameters includes: The pixel coordinates of the head vertices imaged in the image according to the simulated target and the pixel coordinates of the tail vertex , calculate the Euclidean distance between the two points as the pixel size K of the target imaging: ; The pixel coordinates of the head vertices and the pixel coordinates of the tail vertex The midpoint of the line connecting the two points is used as the imaging position of the target image : ; The horizontal right direction of the image is 0° as the reference direction, the counterclockwise direction is the positive angle direction, and the As a starting point, The angle between (w / 2, h / 2) in the image as the starting point and (w, h / 2) as the end point is the pointing angle of the target imaging; where w is the image width and h is the image height.

[0015] Furthermore, adjusting the target infrared radiation characteristic diagram according to the target imaging parameter to obtain the adjusted target infrared image includes: The target infrared radiation characteristic map with the corresponding number is read from the target infrared characteristic map data set, the target infrared radiation characteristic map is scaled proportionally according to the calculated pixel size of the target imaging, the imaging position of the calculated target imaging is used as the imaging position of the background image, and the target infrared radiation characteristic map is rotated according to the pointing angle of the target imaging.

[0016] In a second aspect, the present application further discloses a dynamic flying target infrared simulation system, the system comprising: a target infrared characteristic map data set acquisition module configured to use fluid simulation software to calculate the three-dimensional temperature field data of the simulated target, quantify and render the three-dimensional temperature field data to obtain the target infrared radiation characteristic map, and collect and number the corresponding target infrared radiation characteristic maps by controlling the posture changes of the simulated target, thereby forming a target infrared characteristic map data set; an infrared radiation characteristic diagram acquisition module configured to calculate and output, in real time, the pose data of the simulated target and the aircraft using a real-time simulator, calculate a relative viewing angle based on the pose data of the simulated target and the aircraft, and calculate a number of the corresponding target infrared radiation characteristic diagram using the relative viewing angle; a target imaging calculation module configured to calculate the coordinates of the head and tail vertices of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, convert the coordinates of the head and tail vertices into a pixel coordinate system based on a preset camera imaging model, and calculate target imaging parameters; the target imaging parameters include pixel size, imaging position, and pointing angle; a scene graph generation module configured to read a target infrared radiation characteristic map of a corresponding posture from the target infrared characteristic map data set based on the number of the calculated target infrared radiation characteristic map, and adjust the target size and direction of the target infrared radiation characteristic map according to the target imaging parameters to obtain an adjusted target infrared image, and then read a scene background image, and paste the adjusted target infrared image into the background image according to the calculated target imaging position to form a scene graph with the target infrared characteristics; The dynamic simulation module is configured to output the scene image with the target infrared characteristics to the infrared dynamic target simulator in real time at a fixed frequency, convert the image data into a realistic infrared thermal radiation signal through the infrared dynamic target simulator, and use a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft. Then, the motion control of the five-axis simulation turntable is used to realize the semi-physical simulation of the relative motion simulation detection of the dynamic target.

[0017] Furthermore, the target infrared characteristic map dataset acquisition module specifically includes: a temperature field data calculation unit configured to calculate three-dimensional temperature field data of a simulation target using fluid simulation software; A first image processing unit is configured to quantify the three-dimensional temperature field data and render it to obtain a target infrared radiation characteristic map; The second image processing unit is configured to control the posture change of the simulated target to collect and number the corresponding target infrared radiation characteristic diagrams, thereby forming a target infrared characteristic diagram data set.

[0018] Beneficial effects: 1. Fluid dynamics simulation software is used to calculate the target's three-dimensional temperature field data. By precisely quantifying the mapping relationship between temperature and grayscale values, high-precision infrared radiation characteristic map rendering is achieved. A data acquisition method based on roll and yaw dual-angle interval sampling is specially designed to construct a comprehensive target infrared characteristic map dataset at fixed angle intervals (e.g., 3°), ensuring that the thermal radiation characteristics of each attitude angle can be accurately recorded and reproduced. This data generation method overcomes the limitations of the insufficient accuracy of thermal models in traditional simulations and provides a realistic and reliable data foundation for target dynamic simulation. 2. To meet the high fidelity and real-time requirements of dynamic simulation targets, the present invention pre-generates a high-fidelity target infrared characteristic image dataset. During real-time simulation, the preset camera model is used to calculate the target's imaging parameters and solve the target's posture data. The infrared characteristic map of the target's corresponding posture is retrieved from the collected image library, and the size, position, and direction are adjusted. The simulation scene map is generated in real time in combination with the background, which greatly improves the fluency and realism of the simulation. 3. This invention pioneers dynamic overlay technology for infrared signature images with transparent channels, achieving seamless fusion of target and background by precisely controlling pixel transparency. This establishes a scientific background-target radiation characteristic fusion model, resolving the radiation characteristic mismatch problem common in traditional simulations. This innovative scene generation method significantly enhances the realism of the synthesized images, providing a more reliable simulation environment for infrared detection system testing. 4. Combining the classic pinhole camera model with the target's geometric characteristics, a method for calculating imaging parameters based on the projection of the target's head and tail vertices is proposed. By accurately calculating key parameters such as the target's image size, position, and pointing angle in the pixel coordinate system, the infrared signature image can be intelligently scaled, rotated, and repositioned. This parameterized adjustment method effectively overcomes the distortion of thermal radiation characteristics caused by traditional image deformation, ensuring the accuracy of the target's infrared signature at different distances and postures. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the embodiments or the description of the prior art. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the various elements or parts are not necessarily drawn according to the actual scale. Obviously, the drawings described below are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without inventive work.

[0020] Figure 1 This is a flow chart of an embodiment of a dynamic flying target infrared simulation method of the present application; Figure 2 is a schematic diagram of a structure diagram of a hardware-in-the-loop simulation system for target simulation detection in one embodiment of the present application; Figure 3 This is a flow chart of infrared dynamic target scene generation in one embodiment of the present application; Figure 4 is a schematic diagram of a target coordinate system in one embodiment of the present application; Figure 5 It is a schematic diagram of the module structure of a dynamic flying target infrared simulation system in one embodiment of the present application. DETAILED DESCRIPTION

[0021] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] Herein, suffixes such as "module," "component," or "unit" used to represent elements are only used to facilitate description of the present invention and have no specific meaning. Therefore, "module," "component," or "unit" may be used interchangeably.

[0023] As used herein, terms such as "upper," "lower," "inner," "outer," "front," "back," "one end," and "the other end" indicate positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate and simplify the description of the present invention and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] As used herein, unless otherwise expressly specified or limited, the terms "installed," "provided with," and "connected" should be understood broadly. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; it may refer to a mechanical connection, a direct connection, an indirect connection via an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention on a case-by-case basis.

[0025] As used herein, "and / or" includes any and all combinations of one or more of the associated listed items.

[0026] Herein, "plurality" means two or more than two, ie, it includes two, three, four, five, etc.

[0027] Figure 1 The flowchart of the present invention shows a method for infrared simulation of a dynamic flying target, which specifically includes the following steps: S1 uses fluid simulation software to calculate the three-dimensional temperature field data of the simulated target. The three-dimensional temperature field data is quantified and rendered (using Python's pyvista library to render the temperature field data as a point cloud) to obtain the target infrared radiation characteristic map. By controlling the simulated target's posture changes, the corresponding target infrared radiation characteristic maps are collected and numbered, thus forming a target infrared characteristic map dataset (i.e., a multi-pose infrared characteristic map dataset). During S2 simulation, a real-time simulator is used to calculate and output the pose data of the simulated target and the aircraft in real time. The relative viewing angle is calculated based on the pose data of the simulated target and the aircraft (specifically, the pose data can be obtained by using a scene generation computer and the relative viewing angle is calculated). The number of the corresponding target infrared radiation characteristic diagram is calculated using the relative viewing angle. S3 calculates the coordinates of the head and tail vertices of the simulated target in the camera coordinate system based on the pose data of the simulated target and the aircraft, converts the coordinates of the head and tail vertices to the pixel coordinate system based on the preset camera imaging model, and calculates the target imaging parameters, which include pixel size, imaging position and pointing angle; S4 reads the target infrared radiation characteristic map of the corresponding posture from the target infrared characteristic map data set based on the number of the calculated target infrared radiation characteristic map, and adjusts the target size and direction of the target infrared radiation characteristic map according to the target imaging parameters to obtain an adjusted target infrared image, then reads the scene background image, and pastes the adjusted target infrared image into the background image according to the calculated target imaging position to form a scene image with the target infrared characteristics; S5 outputs a scene image with the target's infrared characteristics to an infrared dynamic target simulator in real time at a fixed frequency. The infrared dynamic target simulator converts the image data into a realistic infrared thermal radiation signal, and uses a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft. The motion control of the five-axis simulation turntable is then used to achieve semi-physical simulation of the relative motion of the dynamic target.

[0028] This embodiment focuses on hardware-in-the-loop simulation of infrared dynamic scenes of aerial targets. First, high-fidelity infrared signature maps of the simulated target (i.e., dynamic target) are generated using temperature field data of the simulated target (i.e., dynamic target) to generate and capture these maps. These maps are then numbered according to their angles, resulting in a dataset of infrared signature images of the simulated target at different poses. During simulation, the simulated target's imaging parameters are calculated using a camera imaging model based on the simulation data. Based on these calculated parameters, infrared radiation signature maps from the corresponding infrared signature map dataset are retrieved and adjusted to simulate targets of any size and pose. Finally, infrared images of the simulated target and background are generated by fusion with the background image at any time, at different distances, and in different poses. The generated real-time sequence of target infrared simulated images is then output to an infrared dynamic target simulator for dynamic simulation of the target's infrared characteristics.

[0029] In a specific embodiment, quantifying and rendering the three-dimensional temperature field data to obtain a target infrared radiation characteristic map includes: The temperature value of each point in the three-dimensional temperature field data is converted and quantized to the range of 0-255 to form the thermal radiation grayscale value of the simulated target, and then rendered to obtain the target infrared radiation characteristic map. In the three-dimensional temperature field data, each point [x, y, z, c] of the simulated target contains the three-dimensional position x, y, z and the temperature value c of the current point.

[0030] In a specific embodiment, collecting and numbering corresponding target infrared radiation characteristic graphs by controlling the posture change of the simulated target includes: By controlling the roll angle of the simulated target around the X-axis from 0 to 360 degrees, with an interval of N degrees (for example, 3 degrees), and adjusting the yaw angle around the Y-axis from 0 to 180 degrees, with an interval of N degrees (for example, 3 degrees), the target infrared radiation characteristic maps of the simulated target in different postures are collected and numbered according to the posture angle information to form a target infrared characteristic map dataset.

[0031] In a specific embodiment, collecting and numbering corresponding target infrared radiation characteristic graphs by controlling the posture change of the simulated target includes: The first digit of the number is the roll angle of the simulated target, the second digit is the relative angle of view between the simulated target and the aircraft, and a dash is used to separate the first and second digits. Of course, in other embodiments, the first digit may be the relative angle of view between the simulated target and the aircraft, the second digit may be the roll angle of the simulated target, and the first and second digits may be separated by a dash.

[0032] In a specific embodiment, the relative viewing angle is calculated based on the pose data of the simulated target and the aircraft, and the number of the corresponding target infrared radiation characteristic diagram is calculated using the relative viewing angle, including: The position of the aircraft is converted to the coordinate system of the simulated target, and the unit vector of the aircraft in the target coordinate system is obtained. The angle between the unit vector of the aircraft in the target coordinate system and the unit vector of the X-axis of the simulated target is calculated. The angle is used as the relative viewing angle and combined with the roll angle of the simulated target itself to solve the corresponding target infrared radiation characteristic diagram number.

[0033] In a specific embodiment, calculating the head and tail vertex coordinates of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, and converting the head and tail vertex coordinates to a pixel coordinate system based on a preset camera imaging model includes: The real-time simulation machine calculates and outputs the pose data of the simulated target and the aircraft in real time as spatial three-dimensional coordinate points in the geodetic coordinate system. According to the pose of the preset camera imaging model in the geodetic coordinate system, the transformation matrix between the camera coordinate system and the geodetic coordinate system is calculated, and the head and tail vertices of the simulated target in the geodetic coordinate system are converted to the camera coordinate system. Then, the pixel coordinate points of the simulated target in the two-dimensional image are calculated according to the three-dimensional coordinate points of the head and tail of the simulated target in the camera coordinate system.

[0034] In a specific embodiment, the target imaging parameters include pixel size, imaging position, and pointing angle.

[0035] In a specific embodiment, calculating the target imaging parameters includes: The pixel coordinates of the head vertices imaged in the image according to the simulated target and the pixel coordinates of the tail vertex , calculate the Euclidean distance between the two points as the pixel size K of the target imaging: ; The pixel coordinates of the head vertices and the pixel coordinates of the tail vertex The midpoint of the line connecting the two points is used as the imaging position of the target image : ; The horizontal right direction of the image is 0° as the reference direction, the counterclockwise direction is the positive angle direction, and the As a starting point, The angle between (w / 2, h / 2) in the image as the starting point and (w, h / 2) as the end point is the pointing angle of the target imaging; where w is the image width and h is the image height.

[0036] In a specific embodiment, adjusting the target infrared radiation characteristic image according to the target imaging parameters to obtain the adjusted target infrared image includes: The target infrared radiation characteristic map with the corresponding number is read from the target infrared characteristic map data set, and the target infrared radiation characteristic map is scaled proportionally according to the calculated pixel size of the target imaging. The calculated imaging position of the target imaging is used as the imaging position of the background image, and the target infrared image is rotated according to the pointing angle of the target imaging.

[0037] In a specific embodiment, the following describes a dynamic flying target infrared simulation method and system of the present application in detail: In this embodiment, the dynamic flying target infrared simulation method relies on the following Figure 2The target simulation detection semi-physical simulation system shown is implemented, which includes an infrared dynamic target simulator, an infrared target detector, a five-axis simulation turntable, a scene generation computer, an external mission computer, a flight control computer and a real-time simulation computer.

[0038] The real-time simulator calculates and outputs the real-time position and attitude data of the simulated target and the aircraft, simulating the relative position of the target relative to the aircraft through a five-axis simulation turntable. The infrared dynamic target simulator is fixedly mounted on the outer two axes of the five-axis simulation turntable system, providing target detection information to the infrared target detector on the inner three axes. The scene generation computer generates dynamic target images from the aircraft's perspective in real time and transmits them to the infrared dynamic target simulator for simulation of the infrared dynamic target scene. The external mission computer is used to provide target detection computing resource support. The flight control computer provides aircraft flight guidance control in semi-physical simulations.

[0039] In the simulation, the infrared dynamic target simulator is used to simulate the infrared optical characteristics of infrared moving targets. The input infrared target image is generated by the scene generation computer in real time. The scene generation computer calculates and updates the target relative to the aircraft's perspective in real time according to the output of the real-time simulator to form a dynamic target scene. The infrared dynamic target scene generation process in the scene generation computer is as follows: Figure 3 shown.

[0040] First, before simulation, the infrared characteristic maps of the target in different postures are calculated and collected to form a target infrared characteristic map data set. The three-dimensional temperature field data of the target is simulated and calculated using fluid software. Each point [x, y, z, c] of the target contains the three-dimensional position and the temperature value information of the current point. The temperature value of each point is converted and quantized to the range of 0-255 to form the target's thermal radiation grayscale value, thereby rendering the target's infrared radiation characteristic map.

[0041] By controlling the target's different postures to form different infrared characteristic images of the target, a certain imaging distance is set during acquisition with a pure black background, and the image resolution size is set to (w, h) so that the target image is in the center of the picture, and the target imaging pixel size is a certain value. .

[0042] Reference Figure 4 In the target coordinate system in the image, the target's attitude change is simulated to roll around the target's x-axis from 0 to 360 degrees at intervals of 3 degrees. Each time the roll angle changes, the yaw attitude around the y-axis changes from 0 to 180 degrees at intervals of 3 degrees. The infrared characteristic image of the target in the current attitude is saved. The image name is numbered with the current target attitude angle information. For example, the first number represents the target's roll angle value, separated by a short line "-", and the second number represents the target's sight angle value, thereby collecting and forming an infrared image dataset with different characteristics of the target.

[0043] During simulation, the scene generation computer reads the position and pitch, yaw, and roll attitude data of the target and aircraft output by the real-time simulator in real time through optical fibers, which are used to calculate the attitude number information and target imaging geometry information of the target. First, the relative viewing angle is calculated based on the position and attitude data of the target and aircraft, and the aircraft position is converted to the target coordinate system to obtain the unit vector of the aircraft in the target coordinate system. , calculate the unit vector The angle with the target X-axis unit vector (1,0,0) , and then use the target's own roll angle Angle Calculate the target infrared feature map number corresponding to this time, and combine the name of the target infrared feature image according to the number, and then read the corresponding name image from the data set to obtain the infrared feature map corresponding to the target at this viewing angle.

[0044] In the target imaging simulation calculation, the camera is modeled using the classic pinhole imaging model to simulate the target imaging size, position, direction and other imaging geometric parameter information. The earth coordinate system, camera coordinate system and pixel coordinate system are constructed during the calculation. The resolution size of the simulated camera output image is set to (w, h), and certain camera internal parameter values ​​are set, including focal length f, unit pixel size and , center pixel and During simulation, the target position output by the real-time simulator is a three-dimensional coordinate point in the earth coordinate system, and its head and tail vertices are and the tail vertex The pose of the simulated camera in the middle is driven by the aircraft pose output by the real-time simulator. The transformation matrix between the camera coordinate system and the earth coordinate system is calculated based on the pose of the camera in the earth coordinate system. , and the head and tail vertices of the target in the geodetic coordinate system and the tail vertex Converted to the camera coordinate system are and Then, the pixel coordinates of the target in the two-dimensional image are calculated based on the three-dimensional coordinates of the target head and tail in the camera coordinate system. and , the calculation method from a spatial point to a two-dimensional pixel coordinate point is as follows: In the formula, f is the focal length of the camera, and is the unit pixel size, and Center point pixel coordinates, is the distance from the target to the camera.

[0045] The pixel coordinates of the target head vertex and tail vertex imaging are obtained by calculation and , then calculate the pixel size K of the image in the target image and the center position of the image , and the pointing angle of the image in the image. According to the pixel values ​​of the head and tail vertices of the target in the image, the distance between the two points is calculated as the target imaging pixel size ; The imaging position of the target is and midpoint between two points ; The imaging direction of the target in the image, in the image, the horizontal right is 0° positive, counterclockwise is positive, and clockwise is negative. starting point The angle between the end point and the starting point (w / 2, h / 2) and the end point (w, h / 2) in the image is the target imaging direction. .

[0046] The target infrared feature map obtained by the calculated target imaging geometry information is mapped and changed. First, the target infrared feature map is read and a transparent layer is added according to the pixel value size in the image. The pixel value of 0 represents full transparency, and the pixel value of 255 represents opaqueness. Thus, the infrared feature map of the target with a transparent layer is obtained, and the target imaging size is obtained by calculation. The target size in the original feature map Compared to the target scaling value scale, the infrared feature map of the target with the transparent layer is scaled proportionally. After the target is scaled, the target is rotated according to the obtained imaging orientation, and the scaled target feature map is rotated according to the calculated target imaging orientation. Read the scene background image and calculate the target imaging position. , paste the target characteristic image with transparent layer after scaling and rotating the target into the background image, so that the target is on the background image. At this point, a scene graph with the target's infrared characteristics is formed. Finally, the synthesized scene graph is output to the target simulator in real time at a fixed frequency (100Hz to ensure program stability) for target simulation. The scene target image is updated in this cycle until the simulation ends.

[0047] By generating dynamic target infrared scenes based on the target infrared characteristic map, the real-time simulation requirements are met, and the infrared target characteristics with high fidelity are realized. At the same time, the relative position relationship between the detector and the target is simulated by using a five-axis turntable, with high control accuracy. The infrared target detector and the target simulator are introduced into the semi-physical simulation loop through the five-axis turntable to improve the credibility of the simulation.

[0048] Further references Figure 5 As an implementation of the above-mentioned method, the present application provides an embodiment of a dynamic flying target infrared simulation method system. Figure 1 Corresponding to the method embodiment shown, the device can be specifically applied to various electronic devices.

[0049] refer to Figure 5 , a dynamic flying target infrared simulation system, comprising: The target infrared characteristic map data set acquisition module 101 is configured to use fluid simulation software to calculate the three-dimensional temperature field data of the simulated target, quantize and render the three-dimensional temperature field data to obtain the target infrared radiation characteristic map, and collect and number the corresponding infrared radiation characteristic maps by controlling the posture changes of the simulated target, thereby forming a target infrared characteristic map data set; The infrared radiation characteristic diagram acquisition module 102 is configured to use a real-time simulator to calculate and output the pose data of the simulated target and the aircraft in real time, calculate the relative viewing angle based on the pose data of the simulated target and the aircraft, and use the relative viewing angle to resolve the number of the corresponding target infrared radiation characteristic diagram; a target imaging calculation module 103 configured to calculate the coordinates of the head and tail vertices of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, convert the coordinates of the head and tail vertices into a pixel coordinate system based on a preset camera imaging model, and calculate target imaging parameters; The scene graph generation module 104 is configured to read an infrared radiation characteristic map of a corresponding posture from the target infrared characteristic map dataset based on the posture data of the simulated target and the aircraft, and adjust the infrared radiation characteristic map according to the target imaging parameters to obtain an adjusted target infrared image, then read a scene background image, and paste the adjusted target infrared image into the background image to form a scene graph having the target infrared characteristics; The dynamic simulation module 105 is configured to output the scene graph with the target infrared characteristics to the infrared dynamic target simulator in real time at a fixed frequency, convert the image data into a realistic infrared thermal radiation signal through the infrared dynamic target simulator, and use a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft, and then perform dynamic simulation of the simulated target through motion control of the five-axis simulation turntable.

[0050] In a specific embodiment, the above-mentioned target infrared characteristic map data set acquisition module 101 specifically includes: a temperature field data calculation unit, configured to use fluid software to simulate and calculate the three-dimensional temperature field data of the simulated target; a first image processing unit, configured to quantify the three-dimensional temperature field data and render it to obtain a target infrared radiation characteristic map; a second image processing unit, configured to control the posture change of the simulated target to collect the corresponding infrared radiation characteristic map and number it, thereby forming a target infrared characteristic map data set.

[0051] As another aspect, the present application also provides a computer-readable storage medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above computer-readable storage medium carries one or more programs, and when the above one or more programs are executed by the electronic device, the electronic device implements the following when executing. Figure 1 The method shown in .

[0052] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0053] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better embodiment. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), including a number of instructions for enabling a computer terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0054] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. A dynamic flying target infrared simulation method, characterized in that: The following steps are involved: Using fluid simulation software to calculate the three-dimensional temperature field data of the simulated target, quantizing and rendering the three-dimensional temperature field data to obtain the target infrared radiation characteristic map, and collecting and numbering the corresponding target infrared radiation characteristic maps by controlling the posture changes of the simulated target, thereby forming a target infrared characteristic map data set; During simulation, a real-time simulator is used to calculate and output the pose data of the simulated target and the aircraft in real time, a relative viewing angle is calculated based on the pose data of the simulated target and the aircraft, and the number of the corresponding target infrared radiation characteristic diagram is solved using the relative viewing angle; Calculating the coordinates of the head and tail vertices of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, converting the coordinates of the head and tail vertices into a pixel coordinate system based on a preset camera imaging model, and calculating target imaging parameters, wherein the target imaging parameters include pixel size, imaging position, and pointing angle; Based on the number of the calculated target infrared radiation characteristic map, the target infrared radiation characteristic map of the corresponding posture is read from the target infrared characteristic map data set, and the target size and direction of the target infrared radiation characteristic map are adjusted according to the target imaging parameters to obtain an adjusted target infrared image, and then the scene background image is read, and the adjusted target infrared image is pasted into the background image according to the calculated target imaging position to form a scene image with the target infrared characteristics; The scene graph with the target infrared characteristics is output to the infrared dynamic target simulator in real time at a fixed frequency. The infrared dynamic target simulator converts the image data into a realistic infrared thermal radiation signal, and uses a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft. Then, the motion control of the five-axis simulation turntable is used to realize the semi-physical simulation of the relative motion simulation detection of the dynamic target.

2. A dynamic flying target infrared simulation method according to claim 1, characterized in that Quantifying the three-dimensional temperature field data and rendering the target infrared radiation characteristic map includes: The radiation brightness of the temperature value of each point in the three-dimensional temperature field data is calculated and quantized to a range of 0-255 to form the thermal radiation grayscale value of the simulated target, and the target infrared radiation characteristic map is obtained by rendering.

3. The infrared simulation method for a dynamic flying target according to claim 1, wherein: The collecting and numbering of corresponding target infrared radiation characteristic diagrams by controlling the posture change of the simulated target includes: By controlling the roll angle of the simulated target around the X-axis from 0 to 360 degrees, with an interval of N degrees, and adjusting the yaw angle around the Y-axis from 0 to 180 degrees, with an interval of N degrees, the target infrared radiation characteristic maps of the simulated target in different postures are collected and numbered according to the posture angle information to form a target infrared characteristic map dataset.

4. The infrared simulation method for a dynamic flying target according to claim 3, wherein: The collecting and numbering of corresponding target infrared radiation characteristic diagrams by controlling the posture change of the simulated target includes: The roll angle or relative viewing angle of the simulated target is used as the first digit of the number, the relative viewing angle or roll angle between the simulated target and the aircraft is used as the second digit of the number, and the first digit and the second digit are separated by a short line.

5. The infrared simulation method for a dynamic flying target according to claim 4, characterized in that: The step of calculating the relative viewing angle based on the pose data of the simulated target and the aircraft, and calculating the number of the corresponding target infrared radiation characteristic diagram using the relative viewing angle includes: The position of the aircraft is converted to the coordinate system of the simulated target, the unit vector of the aircraft in the target coordinate system is obtained, and the angle between the unit vector of the aircraft in the target coordinate system and the unit vector of the X-axis of the simulated target is calculated. The angle is used as the relative viewing angle and combined with the roll angle of the simulated target itself to solve the corresponding target infrared radiation characteristic diagram number.

6. The infrared simulation method for a dynamic flying target according to claim 1, characterized in that: The step of calculating the head and tail vertex coordinates of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, and converting the head and tail vertex coordinates into a pixel coordinate system based on a preset camera imaging model includes: The real-time simulation machine calculates and outputs the pose data of the simulated target and the aircraft in real time as spatial three-dimensional coordinate points in the geodetic coordinate system. According to the pose of the preset camera imaging model in the geodetic coordinate system, the transformation matrix between the camera coordinate system and the geodetic coordinate system is calculated, and the head and tail vertices of the simulated target in the geodetic coordinate system are converted to the camera coordinate system. Then, the pixel coordinate points of the simulated target in the two-dimensional image are calculated according to the three-dimensional coordinate points of the head and tail of the simulated target in the camera coordinate system.

7. The infrared simulation method for a dynamic flying target according to claim 6, characterized in that: The calculation target imaging parameters include: The pixel coordinates of the head vertices imaged in the image according to the simulated target and the pixel coordinates of the tail vertex , calculate the Euclidean distance between the two points as the pixel size K of the target imaging: ； The pixel coordinates of the head vertices and the pixel coordinates of the tail vertex The midpoint of the line connecting the two points is used as the imaging position of the target image : ； The horizontal right direction of the image is 0° as the reference direction, the counterclockwise direction is the positive angle direction, and the As a starting point, The angle between (w / 2, h / 2) in the image as the starting point and (w, h / 2) as the end point is the pointing angle of the target imaging; where w is the image width and h is the image height.

8. The infrared simulation method for a dynamic flying target according to claim 7, characterized in that: The adjusting the target infrared radiation characteristic diagram according to the target imaging parameters to obtain an adjusted target infrared image comprises: The target infrared radiation characteristic map with the corresponding number is read from the target infrared characteristic map data set, the target infrared radiation characteristic map is scaled proportionally according to the calculated pixel size of the target imaging, the imaging position of the calculated target imaging is used as the imaging position of the background image, and the target infrared radiation characteristic map is rotated according to the pointing angle of the target imaging.

9. A dynamic flying target infrared simulation system, characterized in that: include: a target infrared characteristic map data set acquisition module configured to use fluid simulation software to calculate the three-dimensional temperature field data of the simulated target, quantify and render the three-dimensional temperature field data to obtain the target infrared radiation characteristic map, and collect and number the corresponding target infrared radiation characteristic maps by controlling the posture changes of the simulated target, thereby forming a target infrared characteristic map data set; an infrared radiation characteristic diagram acquisition module configured to calculate and output, in real time, the pose data of the simulated target and the aircraft using a real-time simulator, calculate a relative viewing angle based on the pose data of the simulated target and the aircraft, and calculate a number of the corresponding target infrared radiation characteristic diagram using the relative viewing angle; a target imaging calculation module configured to calculate the coordinates of the head and tail vertices of the simulated target in a camera coordinate system based on the pose data of the simulated target and the aircraft, convert the coordinates of the head and tail vertices into a pixel coordinate system based on a preset camera imaging model, and calculate target imaging parameters; the target imaging parameters include pixel size, imaging position, and pointing angle; a scene graph generation module configured to read a target infrared radiation characteristic map of a corresponding posture from the target infrared characteristic map data set based on the number of the calculated target infrared radiation characteristic map, and adjust the target size and direction of the target infrared radiation characteristic map according to the target imaging parameters to obtain an adjusted target infrared image, and then read a scene background image, and paste the adjusted target infrared image into the background image according to the calculated target imaging position to form a scene graph with the target infrared characteristics; The dynamic simulation module is configured to output the scene image with the target infrared characteristics to the infrared dynamic target simulator in real time at a fixed frequency, convert the image data into a realistic infrared thermal radiation signal through the infrared dynamic target simulator, and use a five-axis simulation turntable to simulate the relative viewing angle relationship between the target and the aircraft. Then, the motion control of the five-axis simulation turntable is used to realize the semi-physical simulation of the relative motion simulation detection of the dynamic target.

10. A dynamic flying target infrared simulation system according to claim 9, characterized in that: The target infrared characteristic map data set acquisition module specifically includes: a temperature field data calculation unit configured to calculate three-dimensional temperature field data of a simulation target using fluid simulation software; A first image processing unit is configured to quantify the three-dimensional temperature field data and render it to obtain a target infrared radiation characteristic map; The second image processing unit is configured to control the posture change of the simulated target to collect and number the corresponding target infrared radiation characteristic diagrams, thereby forming a target infrared characteristic diagram data set.

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