Semi-physical simulation device with visible light platform seeker and simulation method

Abstract

The invention discloses a semi-physical simulation device with a visible light platform seeker. The semi-physical simulation device comprises a signal simulation part, a motion simulation part and a test main control part, the signal simulation part comprises a television screen and a target simulation device, and the television screen is connected with the target simulation device; the motion simulation part comprises a three-axis rotary table, the three-axis rotary table comprises a table body and a control cabinet, and a guide head for testing is loaded on the table body; the control cabinet is used for realizing local control of the table body and outputting a real-time sight angle to the target simulation device; the test main control part comprises a seeker, a computer, a simulation machine and a main control computer, the seeker, the computer and the main control computer are connected in sequence, and the main control computer is connected with the simulation machine and the target simulation device. The combination of the television screen and the target simulation device is used for replacing a five-axis rotary table, a visible light source and a parallel light tube, performance verification of the seeker can be rapidly carried out, faster product function verification and version iteration are achieved, and the verification cost is greatly reduced.

Description

Technical Field

[0001] The invention relates to a semi-physical simulation device and a simulation method carrying a visible light platform seeker. Background Art

[0002] With the rapid development of image recognition and AI algorithms, more and more intelligent aircraft are choosing to be equipped with visible light platform seekers. In order to see distant targets clearly, the seeker will adjust the focal length, resulting in a smaller field of view of the seeker. The flight speed of intelligent aircraft is very fast, and a slight interference may cause the target to leave the seeker field of view, resulting in target loss. In order to isolate the influence of the aircraft's attitude movement on the target locking of the seeker, a position marker is added to assist in increasing the adjustable field of view of the seeker.

[0003] In the semi-physical simulation test, after the seeker is installed on the turntable, it can only follow the turntable to perform the attitude movement of the aircraft. At this time, the seeker still stably tracks the target, and its target sight angle changes with the flight trajectory simulation. Therefore, it is necessary to simulate the change in the seeker's sight angle caused by the change in the aircraft position or the target position.

[0004] The conventional test method is to use a five-axis turntable with a visible light source and a collimator for testing. After the seeker is installed on the turntable, the three frames inside, middle and outside the turntable simulate the attitude movement of the aircraft, and the other two frames of pitch and heading are installed with visible light sources and collimators to simulate the line of sight angle movement caused by the change of the spatial position of the aircraft or target. This test method is a conventional method. Due to the rapid development of target tracking and recognition and AI algorithms, there is a situation where conventional test equipment cannot be available in a short time. The five-axis turntable requires a long time to build, and the simulated light source and the corresponding collimator also have high costs. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a semi-physical simulation device of a portable visible light platform seeker with simple structure and reliable operation, and provides a semi-physical simulation method of a portable visible light platform seeker with easy operation.

[0006] The technical solution of the present invention to solve the above technical problems is: a semi-physical simulation device carrying a visible light platform seeker, including a signal simulation part, a motion simulation part and a test main control part; The signal simulation part includes a TV screen and a target simulation device, and the TV screen is connected to the target simulation device; the target simulation device realizes the calibration of the seeker and receives the sight angle signal sent by the main control machine, and generates the size and position information of the target on the TV screen; the TV screen receives the signal generated by the target simulation device for screen projection and display, and is received by the seeker; The motion simulation part includes a three-axis turntable for simulating the pitch, yaw and roll angle position motion of the aircraft. The three-axis turntable includes a platform body and a control cabinet. The platform body is loaded with a test seeker. The control cabinet is used to realize local control of the platform body and output the real-time sight angle to the target simulation device. The main control part of the test includes a seeker, a computer, a simulator and a main control machine. The seeker, the computer and the main control machine are connected in sequence, and the main control machine is connected to the simulator and the target simulation device. The seeker identifies and tracks the target displayed on the TV screen, generates the target's sight angle to the computer, and the computer calculates the control instructions based on the sight angle and the collected gyroscope data. The simulator is used to simulate the spatial position movement of the aircraft, and calculates and updates the current aircraft attitude and ballistic position in real time according to the control instructions calculated by the computer. The main control machine serves as a control terminal provided to the operator to realize visualization functions and data interaction between various components, and saves the simulation test data for analysis after the test.

[0007] The above-mentioned semi-physical simulation device carrying a visible light platform seeker, the platform body serves as the final actuator of the entire three-axis turntable, and includes an inner frame, a middle frame, an outer frame and a base. The inner frame is used to simulate the rotation of the aircraft itself, and the seeker and the computer are fixed on the inner frame; the middle frame is used to simulate the yaw angle movement of the aircraft; and the outer frame is used to simulate the pitch angle movement of the aircraft.

[0008] The above-mentioned semi-physical simulation device carrying a visible light platform seeker, the main control machine is equipped with multiple RS422, RS485 communication interfaces, optical fiber communication interfaces, Ethernet communication interfaces, AD modules, and DA modules. The main control machine realizes real-time signal interaction with the computer through serial port communication and sends line of sight angle signal data to the target simulation device.

[0009] The semi-physical simulation device carrying the visible light platform seeker, wherein the seeker coincides with the rotation center of the three-axis turntable.

[0010] A semi-physical simulation method for a visible light platform seeker includes the following steps: Step 1: Establish a simulation model; Establish the motion control model, data analysis module, data display module, human-computer interaction module and data storage module of the three-axis turntable; Step 2: Initialize and test the three-axis turntable; Step 3: Calibration of the visible light platform seeker; Step 4: Start the semi-physical simulation test; Step 5: Post-test processing; After the test is completed, the parameters obtained from the test are stored in a data storage device, and the control performance is guided by parameter analysis.

[0011] The specific process of step 2 of the semi-physical simulation method of the visible light platform seeker is as follows: The three-axis turntable control system is powered on, and the control cabinet initializes the inner frame, middle frame, and outer frame of the three-axis turntable according to the instructions given by the three-axis turntable control system, controls the inner frame, middle frame, and outer frame to find the initial zero point, and sets the working mode of the inner frame, middle frame, and outer frame as well as the soft limit and soft speed limit values ​​of each frame; The three-axis turntable control system performs static and dynamic tests on the three-axis turntable body to ensure that the three frames of the three-axis turntable body work normally.

[0012] The specific process of step 3 of the semi-physical simulation method of the visible light platform seeker is as follows: The seeker is installed at the center of the inner frame of the three-axis turntable. The rotation centers of the seeker and the three-axis turntable coincide with each other. The lens of the seeker is horizontally facing the TV screen. The current frame angle of the three-axis turntable is fixed. The TV screen is placed 3m away from the seeker. Use the target simulation device to enter the calibration mode. The target is displayed at the center of the TV screen. The target size is first selected as a circle with a diameter of 10 pixels. The position of the TV screen is adjusted to allow the target to enter the seeker field of view or the center of the field of view. Then the seeker locks the target, adjusts the position of the target on the TV screen, records the corresponding frame movement angle of the seeker, calculates the corresponding relationship between pixel point movement and frame angle at the current position, and then fixes the TV screen position.

[0013] In the above-mentioned semi-physical simulation method of the visible light platform seeker, in the step 3, the formula for calculating the corresponding relationship between the pixel point movement and the frame angle at the current position is: ; In the formula, x is the number of pixels moving on the TV screen, L is the distance between the TV screen and the seeker, deg is the frame angle of the seeker movement, p It is the ratio of the moving frame angle of the seeker to the moving pixels of the TV screen.

[0014] The specific process of step 4 of the semi-physical simulation method of the visible light platform seeker is as follows: The simulator controls the three-axis turntable to move to the launch frame angle, enters the simulation mode, powers on all components, and runs the simulator, main control machine, and target simulation device. After the platform is in place, the main control machine controls the seeker to lock onto the target on the TV screen, and then gives a launch signal. The simulator sends the current sight angle to the target simulation device through the main control machine, and the target simulation device simulates and generates the target. The simulator simulates the flight process to control the turntable attitude. The target simulation device simulates the target position and size. The seeker identifies and tracks the target and transmits the sight angle to the computer in real time. The computer receives the sight angle and collects gyro data to calculate the current attitude, and calculates the control instructions according to the guidance information of the seeker. The main control machine receives the control instructions and writes them into the corresponding optical fiber address. The simulator reads the control instructions in the optical fiber address in real time, calculates and corrects the position and attitude information of the aircraft under the current launch system, and drives the turntable at the same time.

[0015] The beneficial effects of the present invention are: 1. The present invention uses a combination of a television screen and a target simulation device to replace a five-axis turntable, a visible light source, and a collimator, which can quickly verify the performance of the seeker, achieve faster product function verification and version iteration, and greatly reduce verification costs.

[0016] 2. The analog signal of the present invention is finally projected and displayed on a TV screen, so the distance between the TV screen and the guide head can be flexibly increased to avoid the problem of the lens being unable to focus and image due to the distance being too close when there is no parallel light tube. The actual distance is related to the size of the TV screen used and the angle range of the guide head's use frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the simulation device of the present invention.

[0018] Figure 2 Schematic diagram of the signal flow of the simulation method of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0020] like Figure 1 As shown, a semi-physical simulation device carrying a visible light platform seeker includes a signal simulation part U1, a motion simulation part U2 and a test main control part U3.

[0021] The signal simulation part U1 includes a TV screen 110 and a target simulation device 120, and the TV screen 110 is connected to the target simulation device 120; the target simulation device 120 realizes the calibration of the seeker 200 and receives the line of sight angle signal sent by the main control computer 160, and generates the size and position information of the target on the TV screen 110; the TV screen 110 receives the signal generated by the target simulation device 120 for screen projection and display, and is received by the seeker 200.

[0022] The motion simulation part U2 includes a three-axis turntable 140 for completing the simulation of the three-channel angular position movement of the pitch, yaw and roll of the aircraft, which can be as close to the actual situation as possible; the three-axis turntable 140 includes a platform 141 and a control cabinet 142, and the platform 141 is loaded with a test seeker 200 to simulate the movement of the aircraft to the greatest extent; the control cabinet 142 is used to realize local control of the platform 141 and output the real-time line of sight angle to the target simulation device 120.

[0023] The test main control part U3 includes a seeker 200, a computer 170, a simulator 150 and a main control machine 160, which are connected in sequence, and the main control machine 160 is connected to the simulator 150 and the target simulation device 120; the seeker 200 identifies and tracks the target displayed on the TV screen 110, generates the target's sight angle to the computer 170, and the computer 170 calculates the control command according to the sight angle and the collected gyro data; the main function of the simulator 150 is to simulate the spatial position movement of the aircraft by using a program pre-written based on at least one of the aircraft kinematics and dynamics model, the target kinematics model, and the aircraft-target relative kinematics model, and calculate and update the current aircraft attitude and ballistic position in real time according to the control command calculated by the computer 170; the main control machine 160 is used as a control terminal provided to the operator to realize the visualization function and the data interaction between the components, and save the simulation test data for analysis after the test is completed. When the program of the simulation machine 150 is running, the main control machine 160 enables the operator to reset the parameters of the program in the simulation machine 150 and control the start and stop of the entire simulation.

[0024] The TV screen 110 is a normal TV screen, including a signal input interface such as HDMI. The larger the size, the better. The display target can also be placed farther away from the seeker 200 to reduce the impact of the focal length. The signal transmission delay and display delay of HDMI are within 40ms, which is a fixed small delay and has little impact on the simulation.

[0025] The target simulation device 120 uses the opencv3.4 library and is written using MFC on the software Visual Studio. The main functions include automatic calibration of the seeker 200 and receiving the sight angle generated by the simulator 150 forwarded by the main control machine 160 through the RS422 serial port to generate the position and size signal of the target on the TV screen 110 and transmit it to the TV screen 110 through the HDMI transmission line. The generated target can select a typical combat target or a recommended target, and can choose to directly generate a pixel map or load a picture, with a personnel operation interface. The target generation time is less than the transmission period of the sight angular velocity of the seeker 200, which is 20ms. If the sight angle data is not received for a long time, the software defaults to stop the simulation, and the simulated target automatically returns to the initial position of the simulation.

[0026] The platform body 141 is the final actuator of the entire three-axis turntable 140, including an inner frame, a middle frame, an outer frame and a base. The inner frame is used to simulate the rotation of the aircraft itself, and the guide head 200 and the computer 170 are fixed on the inner frame; the middle frame is used to simulate the yaw angle movement of the aircraft; and the outer frame is used to simulate the pitch angle movement of the aircraft. The three frames can realize independent movement. The performance indicators of the three-axis turntable used can meet the working conditions at various time points during the program operation.

[0027] During the simulation test, the seeker 200 and the computer 170 are fixed in the inner frame of the turntable. The locking process of the seeker 200 can be operated according to the actual combat process. After locking the target first, the angles of the three frames of the turntable 140 are adjusted to make the platform 141 in the pitch, yaw and roll angles of the aircraft launch state; the frame of the platform 140 can also be adjusted to the launch angle first, and then the frame angle of the seeker 200 is adjusted to lock the target. The launch angle preset of the platform can be selected manually by the control cabinet 142, or the program of the driving angle can be preset directly in the program of the simulator 150. It can be seen that the turntable 140 can be divided into two modes: local control or simulation. In the local mode, the control cabinet 142 can input instructions to test the performance parameters of the platform 141 and whether the functions are normal, and perform operations such as powering on the platform 141. After switching to the simulation mode, the control right of the platform 141 is handed over from the control cabinet 142 to the simulation machine 150. At this time, the platform only receives instructions issued by the simulation machine 150 until the control cabinet 142 exits the simulation.

[0028] The simulator 150 mainly includes a simulation program based on the ballistic mathematical model. The simulation program is programmed in C / C++ using Visual Studio software under the real-time system. It mainly simulates the attitude of the aircraft during flight and calculates the current position of the aircraft in the launch coordinate system in real time. The main external interface is the optical fiber communication interface to communicate with the three-axis turntable 140 and the main control machine 160, and data interaction is carried out by writing and reading data to a fixed address. The optical fiber model is selected as a multi-mode optical fiber. Different optical fiber types correspond to different optical fiber signal receivers. Single-mode and multi-mode receivers and optical fiber lines cannot be mixed.

[0029] The main control machine 160 also uses a real-time operating system, writes programs in Visual Studio software, and adds an independent UI interface as a human-computer main control interface, which mainly completes the data distribution between components and the record retention of key experiments, as well as some signal triggering functions during the experiment. The main control machine 160 is equipped with multiple RS422, RS485 communication interfaces, optical fiber communication interfaces, Ethernet communication interfaces, AD modules, and DA modules. The main control machine 160 realizes real-time signal interaction with the computer 170 and sends the sight angle signal data to the target simulation device 120 through serial port communication. In order to improve the timeliness and data volume of data transmission, it is more advantageous to choose a higher baud rate. Usually, a baud rate of 921600bps, 1 start bit, 8 data bits, 1 stop bit, and serial port attribute settings without parity are selected; optical fiber communication mainly realizes data interaction with the simulation machine 150; the equipped PCI8510 board, PCI1750 board, etc. realize the acquisition of voltage analog quantity and the state acquisition of digital signals to determine the current simulation test stage.

[0030] The rotation center of the guide head 200 coincides with that of the three-axis turntable 140, reducing the error of the field of view angle. The target is displayed at the center of the TV projection screen, avoiding the problem of a small movable angle of a certain field of view.

[0031] A semi-physical simulation method for carrying a visible light platform seeker 200 comprises the following steps: Step 1: Establish a simulation model.

[0032] A motion control model of the three-axis turntable 140 body 141, a data analysis module, a data display module, a human-computer interaction module and a data storage module are established.

[0033] Step 2: Initialize and test the three-axis turntable 140 .

[0034] The specific process of step 2 is: The three-axis turntable 140 control system is powered on, and the control cabinet 142 initializes the inner frame, middle frame and outer frame of the three-axis turntable 140 body 141 according to the instructions given by the three-axis turntable 140 control system, controls the inner frame, middle frame and outer frame to find the initial zero point, sets the working mode of the inner frame, middle frame and outer frame and the soft limit and soft speed limit values ​​of each frame; the three-axis turntable 140 control system performs static and dynamic tests on the three-axis turntable 140 body 141 to ensure that the three frames of the three-axis turntable 140 body 141 are working normally.

[0035] Step 3: Calibration of the visible light platform seeker 200 .

[0036] The specific process of step three is: The seeker head 200 is installed at the center of the inner frame of the three-axis turntable 140, the rotation centers of the seeker head 200 and the three-axis turntable 140 coincide, the lens of the seeker head 200 is horizontally facing the TV screen 110, the current frame angle of the three-axis turntable 140 is fixed, the TV screen 110 is placed at a distance of 3m from the seeker head 200 (based on the comprehensive consideration of the size of the TV screen and the focal length of the seeker head, the seeker head can clearly see the simulated target on the screen), the target simulation device 120 is used to enter the calibration mode, the target is displayed at the center of the TV screen 110, the target size is first selected as a circle with a diameter of 10 pixels, the position of the TV screen 110 is adjusted to allow the target to enter the field of view of the seeker head 200 or the center of the field of view, then the seeker head 200 locks the target, adjusts the position of the target in the TV screen 110, records the corresponding frame movement angle of the seeker head 200, calculates the corresponding relationship between the pixel point movement and the frame angle at the current position, and then fixes the position of the TV screen 110.

[0037] The formula for calculating the correspondence between pixel movement and frame angle at the current position is: ; In the formula, x is the number of pixels moved in the TV screen 110, L is the distance between the TV screen 110 and the guide head 200, deg is the frame angle of the seeker 200 movement, p It is the ratio of the moving frame angle of the seeker 200 to the moving pixel points of the TV screen 110.

[0038] Step 4: Start the semi-physical simulation test.

[0039] The specific process of step 4 is as follows: The simulator 150 controls the three-axis turntable 140 to move to the launch frame angle, enters the simulation mode, powers on all components, and the simulator 150, the main control machine 160, and the target simulation device 120 operate. After the platform 141 is in place, the main control machine 160 controls the seeker 200 to lock onto the target on the TV screen 110, and then gives a launch signal. The simulator 150 sends the current sight angle to the target simulator 120 through the main control machine 160, and the target simulator 120 simulates and generates the target. The simulator 150 simulates the flight process to control the turntable attitude. The target simulator 120 simulates the target position and size. The seeker 200 identifies and tracks the target and transmits the sight angle to the computer 170 in real time. The computer 170 receives the sight angle and collects gyro data to calculate the current attitude, and calculates the control instruction according to the guidance information of the seeker 200. The main control machine 160 receives the control instruction and writes the control instruction into the corresponding optical fiber address. The simulator 150 reads the control instruction in the optical fiber address in real time, calculates and corrects the position and attitude information of the aircraft under the current launch system, and drives the turntable at the same time to complete the control simulation closed loop. By changing the trajectory deviation conditions and repeating step 4, the control and tracking performance under different harsh working conditions can be obtained.

[0040] Step 5: Post-test processing.

[0041] After the test is completed, the parameters obtained from the test are stored in a data storage device, and the control performance is guided by parameter analysis.

Claims

1. A semi-physical simulation device carrying a visible light platform seeker, characterized in that: It includes signal simulation part, motion simulation part and test main control part; The signal simulation part includes a TV screen and a target simulation device, and the TV screen is connected to the target simulation device; the target simulation device realizes the calibration of the seeker and receives the sight angle signal sent by the main control machine, and generates the size and position information of the target on the TV screen; The television screen receives the signal generated by the target simulation device for projection display, and is received by the seeker; The motion simulation part includes a three-axis turntable for simulating the pitch, yaw and roll angle position motion of the aircraft. The three-axis turntable includes a platform body and a control cabinet. The platform body is loaded with a test seeker. The control cabinet is used to realize local control of the platform body and output the real-time sight angle to the target simulation device. The main control part of the test includes a seeker, a computer, a simulator and a main control machine. The seeker, the computer and the main control machine are connected in sequence, and the main control machine is connected to the simulator and the target simulation device. The seeker identifies and tracks the target displayed on the TV screen, generates the target's sight angle to the computer, and the computer calculates the control instructions based on the sight angle and the collected gyroscope data. The simulator is used to simulate the spatial position movement of the aircraft, and calculates and updates the current aircraft attitude and ballistic position in real time according to the control instructions calculated by the computer. The main control machine serves as a control terminal provided to the operator to realize visualization functions and data interaction between various components, and saves the simulation test data for analysis after the test.

2. The semi-physical simulation device carrying a visible light platform seeker according to claim 1 is characterized in that: The platform body serves as the final actuator of the entire three-axis turntable, including an inner frame, a middle frame, an outer frame and a base. The inner frame is used to simulate the rotation of the aircraft itself, and a seeker and a computer are fixed on the inner frame; the middle frame is used to simulate the yaw angle movement of the aircraft; and the outer frame is used to simulate the pitch angle movement of the aircraft.

3. The semi-physical simulation device carrying a visible light platform seeker according to claim 1, characterized in that: The main control machine is equipped with multiple RS422, RS485 communication interfaces, optical fiber communication interfaces, Ethernet communication interfaces, AD modules, and DA modules. The main control machine realizes real-time signal interaction with the computer through serial port communication and sends sight angle signal data to the target simulation device.

4. The semi-physical simulation device carrying a visible light platform seeker according to claim 1, characterized in that: The guide head coincides with the rotation center of the three-axis turntable.

5. A semi-physical simulation method for carrying a visible light platform seeker based on the semi-physical simulation device of claim 2, characterized in that: The following steps are involved: Step 1: Establish a simulation model; Establish the motion control model, data analysis module, data display module, human-computer interaction module and data storage module of the three-axis turntable; Step 2: Initialize and test the three-axis turntable; Step 3: Calibration of the visible light platform seeker; Step 4: Start the semi-physical simulation test; Step 5: Post-test processing; After the test is completed, the parameters obtained from the test are stored in a data storage device, and the control performance is guided by parameter analysis.

6. The semi-physical simulation method of the portable visible light platform seeker according to claim 5 is characterized in that: The specific process of step 2 is: The three-axis turntable control system is powered on, and the control cabinet initializes the inner frame, middle frame, and outer frame of the three-axis turntable according to the instructions given by the three-axis turntable control system, controls the inner frame, middle frame, and outer frame to find the initial zero point, and sets the working mode of the inner frame, middle frame, and outer frame as well as the soft limit and soft speed limit values ​​of each frame; The three-axis turntable control system performs static and dynamic tests on the three-axis turntable body to ensure that the three frames of the three-axis turntable body work normally.

7. The semi-physical simulation method of the portable visible light platform seeker according to claim 5, characterized in that: The specific process of step three is: The seeker is installed at the center of the inner frame of the three-axis turntable. The rotation centers of the seeker and the three-axis turntable coincide with each other. The lens of the seeker is horizontally facing the TV screen. The current frame angle of the three-axis turntable is fixed. The TV screen is placed 3m away from the seeker. Use the target simulation device to enter the calibration mode. The target is displayed at the center of the TV screen. The target size is first selected as a circle with a diameter of 10 pixels. The position of the TV screen is adjusted to allow the target to enter the seeker field of view or the center of the field of view. Then the seeker locks the target, adjusts the position of the target on the TV screen, records the corresponding frame movement angle of the seeker, calculates the corresponding relationship between pixel point movement and frame angle at the current position, and then fixes the TV screen position.

8. The semi-physical simulation method of the portable visible light platform seeker according to claim 7, characterized in that: In step 3, the formula for calculating the corresponding relationship between the pixel movement and the frame angle at the current position is: ； In the formula, x is the number of pixels moving on the TV screen, L is the distance between the TV screen and the seeker, deg is the frame angle of the seeker movement, p It is the ratio of the moving frame angle of the seeker to the moving pixels of the TV screen.

9. The semi-physical simulation method of the portable visible light platform seeker according to claim 5, characterized in that: The specific process of step 4 is as follows: The simulator controls the three-axis turntable to move to the launch frame angle, enters the simulation mode, powers on all components, and runs the simulator, main control machine, and target simulation device. After the platform is in place, the main control machine controls the seeker to lock onto the target on the TV screen, and then gives a launch signal. The simulator sends the current sight angle to the target simulation device through the main control machine, and the target simulation device simulates and generates the target. The simulator simulates the flight process to control the turntable attitude. The target simulation device simulates the target position and size. The seeker identifies and tracks the target and transmits the sight angle to the computer in real time. The computer receives the sight angle and collects gyro data to calculate the current attitude, and calculates the control instructions according to the guidance information of the seeker. The main control machine receives the control instructions and writes them into the corresponding optical fiber address. The simulator reads the control instructions in the optical fiber address in real time, calculates and corrects the position and attitude information of the aircraft under the current launch system, and drives the turntable at the same time.

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