A hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation

Abstract

This invention relates to a hardware-in-the-loop (HIL) testing system for unmanned aerial vehicles (UAVs) based on visual simulation. It falls under the field of UAV testing technology, specifically focusing on HIL testing of UAVs based on visual simulation. The system enables comprehensive testing of UAVs in a laboratory environment. The system includes a seeker, a visual display screen, a visual simulator, the UAV body, a navigation simulator, a three-axis turntable, and a closed-loop simulator. The seeker calculates the miss distance; the visual display screen shows the virtual scene generated by the visual simulator, providing scene data; the UAV body measures the UAV's attitude data; it calculates the UAV's pitch and yaw line-of-sight angular velocities; and it determines the UAV's control variables. The navigation simulator generates navigation signals; the three-axis turntable adjusts the UAV body's attitude in real time; and the closed-loop simulator generates the UAV's position and velocity information, as well as updated attitude data.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) testing technology, and more specifically to the field of UAV hardware-in-the-loop testing technology based on visual simulation. Background Technology

[0002] Unmanned aerial vehicles (UAVs) are increasingly used in military and civilian fields, and their performance and reliability directly affect the success of missions. Traditional UAV testing methods typically rely on actual flight tests, which are not only costly and time-consuming but also subject to limitations imposed by external conditions such as weather and airspace. Therefore, developing a system capable of conducting UAV performance testing in a laboratory environment is of significant practical importance.

[0003] Hardware-in-the-loop (HIL) testing is a testing method that combines actual hardware with simulation models, effectively simulating real-world flight environments and improving the accuracy and reliability of testing. However, existing HIL testing systems have shortcomings in visual and navigation signal simulation, failing to accurately reflect the aircraft's visual perception, navigation signal reception, and seeker's operational status in real-world environments.

[0004] When conducting hardware-in-the-loop testing of visual simulation for controlled aircraft, it is necessary to calculate the aircraft's line-of-sight angular rate based on the aircraft's miss distance. However, there is no direct conversion relationship between the aircraft's miss distance and the line-of-sight angular rate. Traditional methods, when calculating the line-of-sight angular rate, utilize information not only from the line-of-sight angle but also comprehensively consider the aircraft's trajectory information, which not only increases the computational load but also introduces new errors. Summary of the Invention

[0005] To address the problem that existing testing methods cannot accurately reflect the visual perception, navigation signal reception, and seeker status of aircraft in real-world environments, this invention discloses a hardware-in-the-loop testing system for unmanned aerial vehicles (UAVs) based on visual simulation. By organically combining components such as the seeker, aircraft body, closed-loop simulator, three-axis turntable, navigation simulator, visual display screen, and scene simulation software, this invention enables comprehensive testing of UAVs in a laboratory environment. Furthermore, this invention proposes an independently developed method for calculating line-of-sight angular rate, which significantly reduces the error rate.

[0006] The system includes: a seeker head, a visual display screen, a visual simulator, an aircraft body, a navigation simulator, a three-axis turntable, and a closed-loop simulator;

[0007] The seeker head is used to collect scene data on the visual display screen, calculate the miss distance, and send the calculation results to the aircraft body;

[0008] The visual display screen is used to display the virtual scene generated by the visual simulator, providing scene data to the seeker head;

[0009] The visual simulator is used to receive updated aircraft attitude data sent by the closed-loop simulator, generate corresponding virtual scenes in real time, and project them onto the visual display screen.

[0010] The aircraft fuselage is used to receive the miss distance data sent by the seeker;

[0011] Used to measure aircraft attitude data;

[0012] Used to calculate the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of an aircraft;

[0013] Used to determine the control parameters of the aircraft;

[0014] Used to send aircraft attitude data and aircraft control quantities to a closed-loop simulator;

[0015] The navigation simulator is used to receive the aircraft position and velocity information sent by the closed-loop simulator, and to perform coordinate transformation on the aircraft position and velocity information to obtain navigation signals which are then sent to the aircraft body.

[0016] The three-axis turntable is used to receive updated aircraft attitude data sent by the closed-loop simulator and adjust the aircraft's attitude in real time.

[0017] The closed-loop simulator is used to receive and process the aircraft attitude data and aircraft control quantities sent by the aircraft body, and generate aircraft position and velocity information as well as updated aircraft attitude data.

[0018] Used to send aircraft position and speed information to the navigation simulator;

[0019] Used to send updated aircraft attitude data to the three-axis turntable and visual simulator.

[0020] Furthermore, the miss distance includes: the miss distance deviation Δx between the x-axis target point and the center of the field of view. p The deviation Δy between the target point on the y-axis and the center of the field of view p .

[0021] Furthermore, the closed-loop simulator includes: a magnetometer simulator, an accelerometer simulator, a barometer simulator, an airspeed meter simulator, and a dynamics module;

[0022] Magnetometer simulators are used to measure magnetic field strength;

[0023] Accelerometer simulators are used to measure the acceleration of aircraft;

[0024] Barometer simulators are used to measure the air pressure of aircraft;

[0025] Airspeed meter simulators are used to measure the airspeed of aircraft;

[0026] The dynamics module is used to run dynamics models and process data sent by the aircraft.

[0027] Furthermore, the aircraft airframe includes: a navigation receiver, a main control unit, and an inertial measurement unit;

[0028] The main control unit is connected to both the navigation receiver and the inertial measurement unit.

[0029] Furthermore, the measurement of the aircraft attitude data specifically involves: measuring the aircraft attitude data in real time through an inertial measurement unit; the aircraft attitude data includes gyro angular velocity and three-axis angles; the three-axis angles include the aircraft's pitch angle, yaw angle, and roll angle.

[0030] Furthermore, the calculation of the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity specifically involves: running a flight control algorithm through the main control unit to calculate the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity.

[0031] S1. Calculate the pitch angle θ between the seeker's optical axis and the target based on the miss distance and the seeker's camera focal length f. p and yaw angle

[0032] S2, according to θ p and Solve for the pitch line-of-sight angle θ and yaw line-of-sight angle of the aircraft.

[0033] θ = 90 - q - θ p , Where q represents the pitch angle of the aircraft, and r represents the yaw angle of the aircraft;

[0034] S3, for θ and By taking the derivative, we can obtain the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of the aircraft.

[0035] Furthermore, the decision-making of the aircraft control quantity specifically involves the main control unit determining the aircraft control quantity based on the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity combined with sensor data; the sensor data includes: gyro angular velocity, magnetic field strength, aircraft acceleration, aircraft air pressure, and aircraft airspeed.

[0036] Furthermore, the specific steps of receiving and processing the aircraft attitude data and aircraft control quantities sent by the aircraft body to generate aircraft position and velocity information and updated aircraft attitude data are as follows: the dynamics module runs the dynamics model to generate aircraft position and velocity information and updated aircraft attitude data based on the aircraft attitude data and aircraft control quantities.

[0037] The beneficial effects of this invention are as follows:

[0038] (1) The system described in this invention organically combines components such as a seeker head, aircraft body, closed-loop simulator, three-axis turntable, navigation simulator, visual display screen, and scene simulation software to achieve comprehensive testing of unmanned aerial vehicles in a laboratory environment. This system has advantages such as high-precision simulation, realistic scene reproduction, navigation signal simulation, closed-loop control, and laboratory environment testing, which can effectively improve the testing efficiency and reliability of unmanned aerial vehicles.

[0039] (2) High real-time performance: The closed-loop simulator of this invention is built using the PXI real-time simulation system, which has higher real-time performance compared with pure simulation.

[0040] (3) Use real single units as much as possible: The hardware-in-the-loop test system provided by this invention uses real main control unit, inertial measurement unit (IMU), seeker, etc. Compared with traditional aircraft simulation test, only the main control unit is a real single unit, while the other sensors and actuators are simulated models, which can truly simulate the working state of a single unit.

[0041] (4) Communication protocol is consistent with the real machine: In the solution provided by the present invention, the single machine uses the same communication protocol as the real single machine to communicate with the closed-loop simulator or main control unit. Compared with the traditional aircraft simulation experiment, which requires specifying a virtual communication protocol to complete the closed loop, it has a higher degree of simulation.

[0042] (5) The method for calculating line-of-sight angular rate proposed in this invention only uses the relationship between the three-axis attitude information of the aircraft and the rotation angle of the coordinate system obtained from the seeker sampling, thereby reducing error sources and improving calculation accuracy. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the system structure described in an embodiment of the present invention;

[0044] Figure 2 This is a flowchart illustrating the calculation of the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of an aircraft in an embodiment of the present invention.

[0045] 1-Seeker, 2-Visual display screen, 3-Visual simulator, 4-Aircraft body, 401-Power module, 402-Measurement and control module, 403-Navigation receiver, 404-Main control unit, 405-Inertial measurement unit, 5-Navigation simulator, 6-Three-axis turntable, 7-Closed-loop simulator, 701-Magnetometer simulator, 702-Accelerometer simulator, 703-Barometer simulator, 704-Airspeed meter simulator, and 705-Dynamics module. Detailed Implementation

[0046] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] This embodiment provides a hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation. The structure of the system is as follows: Figure 1 As shown, the system includes: a seeker head 1, a visual display screen 2, a visual simulator 3, an aircraft body 4, a navigation simulator 5, a three-axis turntable 6, and a closed-loop simulator 7;

[0048] The guide head 1 is placed on the table, facing the viewing display screen 2;

[0049] The aircraft fuselage 4 is mounted on a three-axis turntable 6;

[0050] The closed-loop simulator 7 is connected to the seeker head 1, the three-axis turntable 6, the visual simulator 3, the navigation simulator 5, and the aircraft body 4, respectively.

[0051] The visual display screen 2 is connected to the visual simulator 3.

[0052] The seeker head 1 is used to collect scene data on the visual display screen 2, calculate the miss distance, and send the calculation results to the aircraft body 4 through the closed-loop simulator 7; the miss distance includes: the deviation Δx between the x-axis target point and the center of the field of view. p The deviation Δy between the target point on the y-axis and the center of the field of view p .

[0053] The visual display screen 2 is used to display the virtual scene generated by the visual simulator 3 and to provide scene data to the guide head 1.

[0054] The visual simulator 3 is used to receive updated aircraft attitude data sent by the closed-loop simulator 7, generate corresponding virtual scenes in real time, and project them onto the visual display screen 2.

[0055] The aircraft body 4 is used to receive the miss distance sent by the seeker 1;

[0056] Used to measure aircraft attitude data;

[0057] Used to calculate the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of an aircraft;

[0058] Used to determine the control parameters of the aircraft;

[0059] Used to send aircraft attitude data and aircraft control quantities to closed-loop simulator 7;

[0060] It is used to receive and update the navigation signals sent by the navigation simulator 5, obtain the updated aircraft position and speed information, and send the updated aircraft position and speed information to the closed-loop simulator 7.

[0061] The navigation simulator 5 is used to receive the aircraft position and velocity information sent by the closed-loop simulator 7, and to perform coordinate transformation on the aircraft position and velocity information to obtain navigation signals which are then sent to the aircraft body 4.

[0062] The three-axis turntable 6 is used to receive updated aircraft attitude data sent by the closed-loop simulator 7 and adjust the attitude of the aircraft body 4 in real time.

[0063] The closed-loop simulator 7 is used to receive and process the aircraft attitude data and aircraft control quantities sent by the aircraft body 4, and generate aircraft position and velocity information as well as updated aircraft attitude data.

[0064] Used to send aircraft position and speed information to navigation simulator 5;

[0065] Used to send updated aircraft attitude data to the three-axis turntable 6 and the visual simulator 3;

[0066] Used to receive and process updated aircraft position and speed information sent by aircraft body 4.

[0067] The closed-loop simulator 7 is built using the PXI real-time simulation system.

[0068] like Figure 1 As shown, the closed-loop simulator 7 includes: a magnetometer simulator 701, an accelerometer simulator 702, a barometer simulator 703, an airspeed meter simulator 704, and a dynamics module 705.

[0069] The magnetometer simulator 701 is used to measure magnetic field strength;

[0070] The accelerometer simulator 702 is used to measure the acceleration of aircraft;

[0071] The 703 barometer simulator is used to measure the air pressure of aircraft.

[0072] The 704 airspeed meter simulator is used to measure the airspeed of aircraft.

[0073] The dynamics module 705 is used to run the dynamics model to process the data sent by the aircraft body 4.

[0074] like Figure 1 As shown, the aircraft body 4 includes: a navigation receiver 403, a main control unit 404, and an inertial measurement unit (IMU) 405; the main control unit 404 is connected to the navigation receiver 403 and the inertial measurement unit (IMU) 405 respectively.

[0075] The specific method for measuring the aircraft attitude data is as follows: the aircraft attitude data is measured in real time by the inertial measurement unit 405; the aircraft attitude data includes gyro angular velocity and three-axis angles; the three-axis angles include the aircraft pitch angle, the aircraft yaw angle and the aircraft roll angle.

[0076] The seeker described in this embodiment is a strapdown seeker, that is, a seeker in which the detector is rigidly connected to the aircraft shell. There is no direct conversion relationship between the miss distance in the pixel coordinate system and the actual line-of-sight angular rate (the pitch line-of-sight angular rate and yaw line-of-sight angular rate of the aircraft). Therefore, it is considered to obtain the relationship between the pitch and yaw angles between the optical axis center of the seeker 1 and the target by using the miss distance and the focal length of the camera of the seeker 1. On this basis, the angle information of the speed calculated by the navigation unit in the launch inertial frame and the three-axis angle information of the aircraft body 4 in the inertial frame calculated by the inertial measurement unit 405 are used to convert the pitch line-of-sight angle and yaw line-of-sight angle of the aircraft through spatial geometric relationship. The corresponding angular rate information is obtained by differentiating the angles respectively.

[0077] like Figure 2 As shown, the calculation of the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity specifically involves: running the flight control algorithm through the main control unit 404 to calculate the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity.

[0078] S1. Based on the miss distance and the focal length f of the camera of the seeker (1), calculate the pitch angle θ between the optical axis of the seeker and the target. p and yaw angle

[0079] S2, according to θ p and Solve for the pitch line-of-sight angle θ and yaw line-of-sight angle of the aircraft.

[0080] θ = 90 - q - θ p , Where w represents the pitch angle of the aircraft, and r represents the yaw angle of the aircraft;

[0081] S3, for θ and By taking the derivative, we can obtain the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of the aircraft.

[0082] The decision to determine the aircraft control quantity is specifically as follows: the main control unit 404 determines the aircraft control quantity based on the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity combined with sensor data; the sensor data includes: gyro angular velocity, magnetic field strength, aircraft acceleration, aircraft air pressure, and aircraft airspeed.

[0083] The navigation receiver 403 is used to provide navigation information to the aircraft body 4 based on the navigation signals sent by the navigation simulator 5.

[0084] The main control unit 404 is used to update the navigation signals sent by the navigation simulator 5, obtain the updated aircraft position and velocity information, and send the updated aircraft position and velocity information to the dynamics module 705.

[0085] The dynamics module 705 receives updated aircraft position and velocity information and combines it with aircraft attitude data to adjust the parameters of the dynamics model to achieve closed-loop control.

[0086] The specific steps of receiving and processing the aircraft attitude data and aircraft control quantities sent by the aircraft body 4 to generate aircraft position and velocity information and updated aircraft attitude data are as follows: The dynamics module 705 runs the dynamics model to generate aircraft position and velocity information and updated aircraft attitude data based on the aircraft attitude data and aircraft control quantities.

[0087] like Figure 1 As shown, the aircraft body 4 also includes a power module 401 and a telemetry and control module 402. The power module 401 is used to supply power to various modules on the aircraft body 4; the telemetry and control module 402 is used to receive wireless command signals from the ground, such as target information loading signals and transmission signals.

Claims

1. A hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation, characterized in that, The system includes: a seeker (1), a visual display screen (2), a visual simulator (3), an aircraft body (4), a navigation simulator (5), a three-axis turntable (6), and a closed-loop simulator (7). The seeker (1) is used to collect scene data on the visual display screen (2), calculate the miss distance, and send the calculation results to the aircraft body (4). The visual display screen (2) is used to display the virtual scene generated by the visual simulator (3) and provide scene data for the guide head (1); The visual simulator (3) is used to receive the updated aircraft attitude data sent by the closed-loop simulator (7), generate the corresponding virtual scene in real time, and project it onto the visual display screen (2); The aircraft body (4) is used to receive the miss distance sent by the seeker (1); Used to measure aircraft attitude data; Used to calculate the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of an aircraft; Used to determine the control parameters of the aircraft; Used to send aircraft attitude data and aircraft control quantities to the closed-loop simulator (7). The calculation of the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity specifically involves: running a flight control algorithm through the main control unit (404) to calculate the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity. S1. Based on the miss distance and the focal length of the camera on the seeker (1) Jointly calculate the pitch angle between the seeker's optical axis and the target. and yaw angle : , ; S2, according to and Solve for the pitch line of sight angle of the aircraft and yaw line of sight : , ,in, Indicates the pitch angle of the aircraft. Indicates the yaw angle of the aircraft; S3, to and By taking the derivative, we can obtain the pitch line-of-sight angular velocity and yaw line-of-sight angular velocity of the aircraft. The navigation simulator (5) is used to receive the aircraft position and speed information sent by the closed-loop simulator (7), and to perform coordinate transformation on the aircraft position and speed information to obtain navigation signals to send to the aircraft body (4). The three-axis turntable (6) is used to receive the updated aircraft attitude data sent by the closed-loop simulator (7) and adjust the attitude of the aircraft body (4) in real time. The closed-loop simulator (7) is used to receive and process the aircraft attitude data and aircraft control quantities sent by the aircraft body (4), and generate aircraft position and speed information as well as updated aircraft attitude data. Used to send aircraft position and speed information to the navigation simulator (5); Used to send updated aircraft attitude data to the three-axis turntable (6) and the visual simulator (3).

2. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 1, characterized in that, The off-target amount includes: Miss deviation between the target point and the center of the field of view and Miss deviation between the target point and the center of the field of view .

3. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 2, characterized in that, The closed-loop simulator (7) includes: a magnetometer simulator (701), an accelerometer simulator (702), a barometer simulator (703), an airspeed meter simulator (704), and a dynamics module (705). The magnetometer simulator (701) is used to measure magnetic field strength; The accelerometer simulator (702) is used to measure the acceleration of an aircraft; The barometer simulator (703) is used to measure the air pressure of aircraft; The airspeed simulator (704) is used to measure the airspeed of an aircraft; The dynamics module (705) is used to run the dynamics model to process the data sent by the aircraft body (4).

4. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 3, characterized in that, The aircraft body (4) includes: a navigation receiver (403), a main control unit (404), and an inertial measurement unit (405); The main control unit (404) is connected to the navigation receiver (403) and the inertial measurement unit (405) respectively.

5. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 4, characterized in that, The specific method for measuring the aircraft attitude data is as follows: the aircraft attitude data is measured in real time by an inertial measurement unit (405); the aircraft attitude data includes gyro angular velocity and three-axis angles; the three-axis angles include the aircraft pitch angle, the aircraft yaw angle and the aircraft roll angle.

6. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 5, characterized in that, The decision to determine the aircraft control quantity is specifically as follows: the main control unit (404) determines the aircraft control quantity based on the aircraft's pitch line-of-sight angular velocity and yaw line-of-sight angular velocity combined with sensor data; the sensor data includes: gyro angular velocity, magnetic field strength, aircraft acceleration, aircraft air pressure and aircraft airspeed.

7. The hardware-in-the-loop testing system for unmanned aerial vehicles based on visual simulation according to claim 6, characterized in that, The specific steps of receiving and processing the aircraft attitude data and aircraft control quantities sent by the aircraft body (4) to generate aircraft position and velocity information and updated aircraft attitude data are as follows: The dynamics module (705) runs the dynamics model to generate aircraft position and velocity information and updated aircraft attitude data based on the aircraft attitude data and aircraft control quantities.

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