CN112634704A - Flight simulation system, method and storage medium - Google Patents
Flight simulation system, method and storage medium Download PDFInfo
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Abstract
The embodiment of the invention relates to the technical field of flight simulation, in particular to a flight simulation system, a flight simulation method and a storage medium, which are used for simulating aerodynamic force and engine acting force received by an aircraft during flight, the method simulates the situation that the moment is unbalanced due to the change of the aerodynamic shape and the speed of the aircraft during the flight process, and adds an automatic balancing unit, the trim system in the real flight process is simulated, the flight trim is carried out on the aircraft through the automatic trim unit, namely, the operation surfaces (ailerons, elevators and rudders) are finely adjusted, unbalanced moment and rod force in a steady state are eliminated, the aim of stabilizing the attitude and the course of the aircraft is achieved, the whole system of the aircraft can be more truly restored, and the flight state of the aircraft is completely simulated, so that the state and the operation data of the aircraft in flight simulation training are more fit with a real flight scene.
Description
Technical Field
The embodiment of the application relates to the technical field of flight simulation, in particular to a flight simulation system, a flight simulation method and a storage medium.
Background
The requirements of the aircraft as a complex air vehicle for the pilot are much more complex, and it is also a very complex task to maneuver it. The pilot is trained on the aircraft, so that the cost is high, and the safety is difficult to guarantee. The flight simulation system is used for flight training and flight research, the development of flight simulation is synchronous with the development of an aircraft, and the flight simulation system has the advantages of safety, reliability, energy and cost saving, and is not limited by weather, time, places and the like.
The traditional flight simulation is to simulate various flight environments, collect operation parameters in the training process, compare the operation parameters with reference parameters to realize flight training tests, and only simulate an operating system, so that the simulation model has a great difference from the actual flight environment of the aircraft.
Disclosure of Invention
The invention aims to provide a flight simulation system, a flight simulation method and a storage medium, and solves the problem that in the prior art, the simulation of an aircraft is only limited to the simulation of an operating system, so that a simulation model and the actual flight environment of the aircraft have a large difference.
In order to solve the above technical problem, in a first aspect, an embodiment of the present invention provides a flight simulation system, including a flight dynamics unit and an automatic balancing unit;
the flight dynamics unit simulates aerodynamic parameters and engine acting force parameters of an aircraft to simulate, and resolves flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
and the automatic balancing unit is used for carrying out flight balancing on the aircraft according to the flight state parameters.
In a second aspect, an embodiment of the present invention provides a flight simulation method, including:
simulating aerodynamic parameters and engine acting force parameters received by an aircraft during flying, and calculating flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
and carrying out flight balancing on the aircraft according to the flight state parameters.
In a third aspect, an embodiment of the present invention provides a non-transitory computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of the in-flight simulation method according to an embodiment of the second aspect of the present invention.
Compared with the prior art, the embodiment of the invention simulates the unbalanced moment condition caused by the change of aerodynamic shape and speed of the aircraft in the flying process by simulating the aerodynamic force and the engine acting force received by the aircraft in the flying process, adds the automatic balancing unit, simulates the balancing system in the real flying process, performs flying balancing on the aircraft by the automatic balancing unit, namely finely adjusts the operation surfaces (ailerons, elevators and rudders), eliminates the unbalanced moment and the rod force in a steady state, achieves the aim of stabilizing the attitude and the course of the aircraft, can more truly restore the whole system of the aircraft, and completely simulates the flying state of the aircraft so that the state and the operation data of the aircraft in the flying simulation training are more fit with the real flying scene.
Additionally, the flight dynamics unit includes an aerodynamic module, an engine module, and an equation of motion module;
the aerodynamic module is used for simulating atmospheric data, determining aerodynamic parameters of the aircraft according to the atmospheric data, wherein the aerodynamic parameters comprise one or a combination of the following components: resistance, lateral force, lift, roll moment, pitch moment, and yaw moment;
the engine module is used for simulating engine acting force parameters, and the engine acting force parameters comprise engine acting force and engine torque under the body coordinates provided by an engine;
the motion equation module is used for simulating a full equation of the degree of freedom dynamics of the aircraft, completing calculation of a six-degree-of-freedom rigid body motion equation of the aircraft, and calculating flight state parameters of the aircraft according to the pneumatic force parameters and the engine acting force parameters.
Additionally, the step of the engine module simulating engine force parameters comprises:
when the engine is started, calculating the rotating speed of a high-pressure rotor of the engine, calculating the rotating speed of a low-pressure rotor according to the rotating speed of the high-pressure rotor, and igniting and activating the engine if the rotating speed of the low-pressure rotor is judged to reach a preset ignition threshold value;
calculating the instantaneous throttle valve flow of the engine;
determining a total thrust, a ram resistance and a net thrust of the single engine from the throttle flow;
and calculating the engine acting force and the engine moment under the body coordinate according to the mounting pitch angle, the camber angle and the mounting position of the engine, the total thrust, the stamping resistance and the net thrust.
In addition, the flight dynamics unit further comprises a landing gear module, and the landing gear module is connected with the motion equation module;
the undercarriage module is used for calculating undercarriage acting force and undercarriage moment under an airframe coordinate provided by the undercarriage; and sending the undercarriage acting force and the undercarriage moment to the motion equation module so that the motion equation module can solve the flight state parameters of the flight simulator in the takeoff phase according to the undercarriage acting force, the undercarriage moment, the aerodynamic force parameters and the engine acting force parameters.
In addition, the step of the landing gear module calculating landing gear effort and landing gear moment in body coordinates provided by the landing gear comprises:
calculating the interaction force of the wheel, the strut and the damping device under a ground coordinate system and the supporting force provided for the aircraft;
determining the friction force of the airplane wheel according to the speed, the Euler angle and the angular speed of the airplane wheel and the supporting force;
and converting the friction force into an undercarriage acting force under an airframe coordinate, and determining an undercarriage moment according to the position of the airplane wheel relative to the gravity center of the aircraft.
In addition, the flight dynamics unit further comprises a mass characteristic module, wherein the mass characteristic module is used for simulating the fuel consumption mass change of the aircraft, and determining the mass, the mass center and the rotational inertia of the aircraft according to the fuel consumption mass change.
In addition, the system also comprises a navigation sensing unit, an automatic driving unit and a flight control unit;
the navigation sensing unit is used for simulating positioning information of the aircraft, determining attitude information of the aircraft according to the flight state parameters, and transmitting the positioning information and the attitude information to the automatic driving unit;
the automatic pilot unit is used for simulating a flight automatic control system of the aircraft, and the flight automatic control system is used for generating automatic pilot data according to the attitude information and the positioning information; the flight automatic control system comprises a damper, a stability augmentation system, a control stability augmentation system and an automatic flight system;
the flight control unit is used for receiving the automatic driving data so as to control the aircraft to carry out unmanned flight; and receiving an operation signal, and obtaining control surface information and rod information after control law processing so as to realize manned flight of the aircraft.
In addition, the navigation sensing unit comprises an inertial navigation module, a global positioning module and a flight system calculation module;
the inertial navigation module is used for determining a navigation coordinate system and determining the position and the speed of the aircraft in the navigation coordinate system according to the flight state parameters;
the global positioning module is used for determining positioning information and attitude information of the aircraft in the navigation coordinate system;
the flight system calculation module is configured to transmit the positioning information and the attitude information to the autopilot unit.
Drawings
One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.
FIG. 1 is a block diagram of a flight simulation system according to a first embodiment of the present invention;
FIG. 2 is a block diagram of a flight simulation system according to a second embodiment of the present invention;
FIG. 3 is a block diagram of a flight simulation system according to a third embodiment of the present invention;
fig. 4 is a block diagram of a server according to a fifth embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in order to provide a better understanding of the present application in various embodiments of the present invention. However, the technical solution claimed in the present application can be implemented without these technical details and various changes and modifications based on the following embodiments. The following embodiments are divided for convenience of description, and should not constitute any limitation to the specific implementation manner of the present invention, and the embodiments may be mutually incorporated and referred to without contradiction.
The terms "first" and "second" in the embodiments of the present application are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, the terms "comprise" and "have", as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a system, product or apparatus that comprises a list of elements or components is not limited to only those elements or components but may alternatively include other elements or components not expressly listed or inherent to such product or apparatus. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise.
The existing simulation model usually simulates the flight state in a fixed environment, compares the operation data with the reference data by collecting the operation data in the simulation training process to realize the training test, does not simulate a complete flight system, and only simulates the operation system, so that the simulation model has a larger difference with the actual flight environment of the aircraft.
Accordingly, embodiments of the present invention provide a flight simulation system, method and storage medium that, by simulating aerodynamic and engine forces received by an aircraft during flight, so as to simulate the situation that the moment is unbalanced due to the change of the aerodynamic shape and the speed of the aircraft during the flight process, and add an automatic balancing unit, the trim system in the real flight process is simulated, the flight trim is carried out on the aircraft through the automatic trim unit, namely, the operation surfaces (ailerons, elevators and rudders) are finely adjusted, unbalanced moment and rod force in a steady state are eliminated, the aim of stabilizing the attitude and the course of the aircraft is achieved, the whole system of the aircraft can be more truly restored, and the flight state of the aircraft is completely simulated, so that the state and the operation data of the aircraft in flight simulation training are more fit with a real flight scene. The following description and description will proceed with reference being made to various embodiments.
A first embodiment of the invention relates to a flight simulation system. As shown in fig. 1, the flight simulation system comprises a flight dynamics unit 10 and an automatic trim unit 20;
the flight dynamics unit 10 is used for simulating an aircraft, simulating aerodynamic parameters and engine acting force parameters received by the aircraft during flight, and calculating flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
specifically, aerodynamic force is the resultant of pressure and tangential force acting on the surface of an aircraft when the aircraft and air move relative to each other. Depending on factors such as flight speed, flight altitude, flight conditions, aircraft geometry and dimensions. The system can be specifically decomposed into 3 component forces of lift force, resistance force and lateral force.
In the embodiment, aerodynamic force received by the aircraft during flying is simulated, an aerodynamic mathematical model of the fixed-wing aircraft is included, and a model template for simulation calculation is formed, wherein wings are main components of the aircraft for generating lift force, and when an aerodynamic force action point deviates from the gravity center, a pitching moment, a directional moment and a rolling moment are generated; the resistance, the lateral force, the lift force, the rolling moment, the pitching moment, the yawing moment and various coefficients of the aircraft are directly output after input parameters are calculated, so that the air flow of the aircraft is simulated, and the forces and the moments in the x direction, the y direction and the z direction are obtained.
And the automatic balancing unit 20 is configured to perform flight balancing on the aircraft according to the flight state parameters.
Specifically, in the flying process of the airplane, due to the change of the aerodynamic shape and the speed, moment imbalance can be caused, normal flying is influenced, the flying trim has the function of eliminating unbalanced moment and stick force in a steady state, and a trim control system can enable a pilot to control a control surface under the conditions of different loads and airspeeds to realize the balance of wing lift force and resistance, so that the control force required for adjusting or maintaining the attitude of the airplane can be effectively reduced. The auto-trim unit 20 in this embodiment is a software package that allows for batch runs of aircraft trim and flight simulations.
The auto-trim unit 20 is used directly with an aircraft flight dynamics unit built with Simulink. In order to accelerate the simulation speed, the binary file which is automatically generated can be used. The auto-trim unit 20 also has a separate graphical interface to facilitate trim, input, parameter estimation and batch file setup. The auto-trim unit 20 performs some basic trim by default, such as radial and lateral trim of the aircraft; and some reference velocities are automatically calculated.
The automatic trim model can also automatically estimate parameters in batches for flight dynamics analysis. The method of parameter estimation is applicable to both static trim and dynamic steering flight. The main functions are as follows:
1. automatic balancing configuration
The auto-trim configuration function enables any point within the aircraft envelope to be balanced by adjusting the inputs, states and outputs of the flight dynamics unit 10. In the trim editor interface, a trim file may be created. The trim file contains aircraft configuration information such as weight, speed, attitude, flap down, etc. The automatic balancing system can automatically calculate the balancing state corresponding to the balancing file, and the balancing algorithm is fast, flexible and stable. The airplane model can reach various stable states without running. Thus providing an initial state for small perturbation analysis of aircraft dynamics.
2. Parameter matching
And adjusting parameters of the model to obtain better model confidence. The inputs, outputs and various parameters of the model are selected in a parameter editing interface of the auto-trim unit 20, and the auto-trim unit 20 automatically adjusts the parameters of the flight dynamics unit 10 so that the output of the flight dynamics unit 10 matches the measured flight values of the aircraft with the minimum variance. The resulting flight dynamics unit 10 is the model closest to the actual aircraft.
3. Batch balancing and parameter matching
The ability of the auto-trim unit 20 is more apparent in batch runs where trim of multiple points is matched to parameters. In the batch trim interface, trim conditions including different airframe weights, flight speeds, control plane deflection angles, etc. may be established in chronological order. The automatic trim unit 20 may perform trim for a plurality of states and simulation runs after trim. The balanced result can be stored in a database for subsequent simulation test calling. Parameter matching can also be performed in batches. Each parameter matching comprises a parameter matching setting file, a trim file and a flight actual measurement data file. The automatic trim unit 20 will automatically run a batch of parameter matches based on these files.
The automatic trim unit 20 can conveniently perform the trimming, the operation input, the state calculation and the batch trim calculation of the real-time model of the airplane on the graphical user interface.
A second embodiment of the invention relates to a flight simulation system. The second embodiment is a refinement of the first embodiment. In a second embodiment of the invention, the flight dynamics unit 10 comprises an aerodynamic module 101, a landing gear module 103, an engine module 102, a mass characteristics module 104 and an equation of motion module 105. As shown in fig. 2, the flight simulation system comprises a flight dynamics unit 10 and an automatic trim unit 20;
the flight dynamics unit 10 is configured to establish an aircraft, simulate an aerodynamic parameter and an engine acting force parameter that the aircraft receives during flight, and calculate a flight state parameter of the aircraft under the aerodynamic parameter and the engine acting force parameter;
in particular, the flight dynamics unit 10 comprises an aerodynamic module 101, a landing gear module 103, an engine module 102, a mass characteristics module 104 and an equation of motion module 105;
the aerodynamic module 101 is configured to simulate atmospheric data, and determine aerodynamic parameters of the aircraft according to the atmospheric data, where the aerodynamic parameters include resistance, lateral force, lift force, rolling moment, pitching moment, and yawing moment; wherein, by providing absolute temperature, pressure, density, sound velocity and altitude reference, atmospheric data such as airspeed and the like can be calculated, and factors such as attack angle, sideslip angle, dynamic pressure, temperature, altitude, wind power and the like are considered in the calculation process.
Aerodynamic force is the resultant of pressure and tangential force acting on the surface of an aircraft when the aircraft and air move relative to each other. Depending on factors such as flight speed, flight altitude, flight conditions, aircraft geometry and dimensions. The system can be specifically decomposed into 3 component forces of lift force, resistance force and lateral force. In the embodiment, aerodynamic force received by the aircraft during flying is simulated, an aerodynamic mathematical model of the fixed-wing aircraft is included, and a model template for simulation calculation is formed, wherein wings are main components of the aircraft for generating lift force, and when an aerodynamic force action point deviates from the gravity center, a pitching moment, a directional moment and a rolling moment are generated; the resistance, the lateral force, the lift force, the rolling moment, the pitching moment, the yawing moment and various coefficients of the aircraft are directly output after input parameters are calculated, so that the air flow of the aircraft is simulated, and the forces and the moments in the x direction, the y direction and the z direction are obtained.
The engine module 102 is configured to simulate an engine of the aircraft, and determine engine acting force parameters received by the aircraft, where the engine acting force parameters include an engine acting force and an engine torque provided by the engine in body coordinates; the method comprises the following steps:
when the aircraft is started, calculating the rotating speed of a high-pressure rotor of an engine, calculating the rotating speed of a low-pressure rotor according to the rotating speed of the high-pressure rotor, and igniting and activating the engine if the rotating speed of the low-pressure rotor is judged to reach a preset ignition threshold value;
calculating the instantaneous throttle valve flow of the engine;
determining a total thrust, a ram resistance and a net thrust of the single engine from the throttle flow;
and calculating the engine acting force and the engine moment in the direction X, Y, Z under the body coordinate according to the mounting pitch angle, the camber angle and the mounting position of the engine, the total thrust, the stamping resistance and the net thrust.
The undercarriage module 103 is used for calculating undercarriage acting force and undercarriage moment under an airframe coordinate provided by an undercarriage; and sending the landing gear acting force and the landing gear moment to the motion equation module 105, so that the motion equation module 105 calculates flight state parameters of a takeoff phase of the flight simulator according to the landing gear acting force, the landing gear moment, the aerodynamic force parameters and the engine acting force parameters. The method comprises the following steps:
calculating the interaction force of the wheel, the strut and the damping device under a ground coordinate system and the supporting force provided for the aircraft;
determining the friction force of the airplane wheel according to the speed, the Euler angle and the angular speed of the airplane wheel and the supporting force;
and converting the friction force into an undercarriage acting force under an airframe coordinate, and determining an undercarriage moment according to the position of the airplane wheel relative to the gravity center of the aircraft.
In this embodiment, the flight dynamics unit 10 can completely simulate the flight process, and can simulate multiple systems of the airplane, thereby completing real-time simulation of each stage of the airplane, such as takeoff, climbing, cruising, maneuvering, landing, running and the like.
The mass characteristics module 104 simulates the effect of changes in the aircraft mass, center of mass, and moment of inertia on the aircraft performance and handling characteristics. The weight of the aircraft is calculated from the gross weight minus the total fuel consumption. According to the fuel consumption of the airplane, the change of the weight center of gravity and the moment of inertia of the airplane is simulated. The mass characteristic model simulates the mass change of fuel consumption and the change of the center of gravity and the rotational inertia of the airplane caused by fuel imbalance. The weight, center of gravity, and moment of inertia of the aircraft are collectively referred to as mass characteristics. The mass characteristics affect the work of the airplane in various fields such as load, performance, stability and flutter, and because the fuel consumption has great influence on the airplane mass, the fuel occupies a large proportion in the weight of the whole airplane, taking B737-400 as an example: the empty weight is 33 tons, the fuel oil is 18.5 tons, and the passenger carrying capacity is 150 people (about 10.5 tons), and the total weight is about 62 tons. Fuel accounts for nearly one third of the total weight. The aircraft can continuously fly for 4000 km, the endurance time is about 5 hours, and the average oil consumption per hour is more than 3 tons, which is about 1/20 of the total weight. It can be seen that the effect of fuel consumption on aircraft quality during flight is significant. Therefore, in the present embodiment, the influence of fuel consumption on the performance and handling characteristics of the aircraft is also simulated with emphasis.
The motion equation module 105 is configured to simulate a six-degree-of-freedom dynamic full equation of an aircraft, complete calculation of a six-degree-of-freedom rigid motion equation of the aircraft, and finally calculate flight state parameters of the aircraft according to the aerodynamic force parameters and the engine force parameters, including aerodynamic force and moment (resistance, lateral force, lift force, rolling moment, pitching moment and yawing moment), ground reaction force and moment, and aircraft motion response during engine force and engine moment.
And the automatic balancing unit 20 is configured to perform flight balancing on the aircraft according to the flight state parameters.
Specifically, in the flying process of the airplane, due to the change of the aerodynamic shape and the speed, moment imbalance can be caused, normal flying is influenced, the flying trim has the function of eliminating unbalanced moment and stick force in a steady state, and a trim control system can enable a pilot to control a control surface under the conditions of different loads and airspeeds to realize the balance of wing lift force and resistance, so that the control force required for adjusting or maintaining the attitude of the airplane can be effectively reduced. The auto-trim unit 20 in this embodiment is a software package that allows for batch runs of aircraft trim and flight simulations.
The auto-trim unit 20 is used directly with the aircraft flight dynamics unit 10 built with Simulink. In order to accelerate the simulation speed, the binary file which is automatically generated can be used. The auto-trim unit 20 also has a separate graphical interface to facilitate trim, input, parameter estimation and batch file setup. The auto-trim unit 20 performs some basic trim by default, such as radial and lateral trim of the aircraft; and some reference velocities are automatically calculated.
The automatic trim model can also automatically estimate parameters in batches for flight dynamics analysis. The method of parameter estimation is applicable to both static trim and dynamic steering flight. The main functions are as follows:
1. automatic balancing configuration
The auto-trim configuration function enables any point within the aircraft envelope to be balanced by adjusting the inputs, states and outputs of the flight dynamics unit 10. In the trim editor interface, a trim file may be created. The trim file contains aircraft configuration information such as weight, speed, attitude, flap down, etc. The automatic balancing system can automatically calculate the balancing state corresponding to the balancing file, and the balancing algorithm is fast, flexible and stable. The airplane model can reach various stable states without running. Thus providing an initial state for small perturbation analysis of aircraft dynamics.
2. Parameter matching
And adjusting parameters of the model to obtain better model confidence. The inputs, outputs and various parameters of the model are selected in a parameter editing interface of the auto-trim unit 20, and the auto-trim unit 20 automatically adjusts the parameters of the flight dynamics unit 10 so that the output of the flight dynamics unit 10 matches the measured flight values of the aircraft with the minimum variance. The resulting flight dynamics unit 10 is the model closest to the actual aircraft.
3. Batch balancing and parameter matching
The ability of the auto-trim unit 20 is more apparent in batch runs where trim of multiple points is matched to parameters. In the batch trim interface, trim conditions including different airframe weights, flight speeds, control plane deflection angles, etc. may be established in chronological order. The automatic trim unit 20 may perform trim for a plurality of states and simulation runs after trim. The balanced result can be stored in a database for subsequent simulation test calling. Parameter matching can also be performed in batches. Each parameter matching comprises a parameter matching setting file, a trim file and a flight actual measurement data file. The automatic trim unit 20 will automatically run a batch of parameter matches based on these files.
The automatic trim unit 20 can conveniently perform the trimming, the operation input, the state calculation and the batch trim calculation of the real-time model of the airplane on the graphical user interface.
A third embodiment of the invention is directed to a flight simulation system. The third embodiment is a refinement of the second embodiment. In the third embodiment of the present invention, as shown in fig. 3, further comprising a navigation sensing unit 30, an autopilot unit 40 and a flight control unit 50, the flight simulation system comprises a flight dynamics unit 10, an auto-trim unit 20, a navigation sensing unit 30, an autopilot unit 40 and a flight control unit 50;
the flight dynamics unit 10 is configured to establish an aircraft, simulate an aerodynamic parameter and an engine acting force parameter that the aircraft receives during flight, and calculate a flight state parameter of the aircraft under the aerodynamic parameter and the engine acting force parameter;
specifically, aerodynamic force is the resultant of pressure and tangential force acting on the surface of an aircraft when the aircraft and air move relative to each other. Depending on factors such as flight speed, flight altitude, flight conditions, aircraft geometry and dimensions. The system can be specifically decomposed into 3 component forces of lift force, resistance force and lateral force.
In the embodiment, aerodynamic force received by the aircraft during flying is simulated, an aerodynamic mathematical model of the fixed-wing aircraft is included, and a model template for simulation calculation is formed, wherein wings are main components of the aircraft for generating lift force, and when an aerodynamic force action point deviates from the gravity center, a pitching moment, a directional moment and a rolling moment are generated; the resistance, the lateral force, the lift force, the rolling moment, the pitching moment, the yawing moment and various coefficients of the aircraft are directly output after input parameters are calculated, so that the air flow of the aircraft is simulated, and the forces and the moments in the x direction, the y direction and the z direction are obtained.
The navigation sensing unit 30 is configured to simulate positioning information of the aircraft, determine attitude information of the aircraft according to the flight state parameter, and transmit the positioning information and the attitude information to the autopilot unit 40; the navigation sensing unit 30 comprises an inertial navigation module 301, a global positioning module 302 and a flight system calculation module 303;
the inertial navigation module 301 is configured to determine a navigation coordinate system, and determine a position and a speed of the aircraft in the navigation coordinate system (global positioning system) according to the flight state parameter;
the global positioning module 302 is configured to simulate a global positioning system, and determine positioning information and attitude information of the aircraft in the global positioning system;
the flight system calculation module 303 is configured to transmit the positioning information and the attitude information to the autopilot unit 40.
The autopilot unit 40, which includes a stabilization loop and a control (guidance) loop, is configured to simulate an automatic flight control system of the aircraft, and the automatic flight control system is configured to generate autopilot data according to the attitude information and the positioning information; the flight automatic control system comprises a damper, a stability augmentation system, a control stability augmentation system and an automatic flight system;
the flight control unit 50 is configured to receive the autopilot data to control the aircraft to perform unmanned flight; and receiving an operation signal, and obtaining control surface information and rod information after control law processing so as to realize manned flight of the aircraft.
And the automatic balancing unit 20 is configured to perform flight balancing on the aircraft according to the flight state parameters.
Specifically, in the flying process of the airplane, due to the change of the aerodynamic shape and the speed, moment imbalance can be caused, normal flying is influenced, the flying trim has the function of eliminating unbalanced moment and stick force in a steady state, and a trim control system can enable a pilot to control a control surface under the conditions of different loads and airspeeds to realize the balance of wing lift force and resistance, so that the control force required for adjusting or maintaining the attitude of the airplane can be effectively reduced. The auto-trim unit 20 in this embodiment is a software package that allows for batch runs of aircraft trim and flight simulations.
The auto-trim unit 20 is used directly with the aircraft flight dynamics unit 10 built with Simulink. In order to accelerate the simulation speed, the binary file which is automatically generated can be used. The auto-trim unit 20 also has a separate graphical interface to facilitate trim, input, parameter estimation and batch file setup. The auto-trim unit 20 performs some basic trim by default, such as radial and lateral trim of the aircraft; and some reference velocities are automatically calculated.
The automatic trim model can also automatically estimate parameters in batches for flight dynamics analysis. The method of parameter estimation is applicable to both static trim and dynamic steering flight.
The steps of the above methods are divided for clarity, and the implementation may be combined into one step or split some steps, and the steps are divided into multiple steps, so long as the same logical relationship is included, which are all within the protection scope of the present patent; it is within the scope of the patent to add insignificant modifications to the algorithms or processes or to introduce insignificant design changes to the core design without changing the algorithms or processes.
The fourth embodiment of the present invention relates to a flight simulation method, by which a flight simulation system as described in the above embodiments can be built, the method including:
establishing an aircraft, simulating aerodynamic parameters and engine acting force parameters received by the aircraft during flying, and resolving flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
and carrying out flight balancing on the aircraft according to the flight state parameters.
A fifth embodiment of the present invention relates to a server, as shown in fig. 4, including a processor (processor)810, a communication Interface (Communications Interface)820, a memory (memory)830 and a communication bus 840, where the processor 810, the communication Interface 820 and the memory 830 complete communication with each other through the communication bus 840. The processor 810 may invoke logic instructions in the memory 830 to perform the steps of the flight simulation method as described in the various embodiments above.
Where the memory and processor are connected by a communications bus, which may include any number of interconnected buses and bridges, connecting together the various circuits of the memory and one or more processors. The bus may also connect various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. A bus interface provides an interface between a communication bus and a transceiver. The transceiver may be one element or a plurality of elements, such as a plurality of receivers and transmitters, providing a means for communicating with various other apparatus over a transmission medium. The data processed by the processor is transmitted over a wireless medium via an antenna, which further receives the data and transmits the data to the processor.
The processor is responsible for managing the bus and general processing and may also provide various functions including timing, peripheral interfaces, voltage regulation, power management, and other control functions. And the memory may be used to store data used by the processor in performing operations.
A sixth embodiment of the present invention relates to a computer-readable storage medium storing a computer program. The computer program, when executed by a processor, implements the steps of the flight simulation method as described in the various embodiments above.
That is, as can be understood by those skilled in the art, all or part of the steps in the method for implementing the embodiments described above may be implemented by a program instructing related hardware, where the program is stored in a storage medium and includes several instructions to enable a device (which may be a single chip, a chip, or the like) or a processor (processor) to execute all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.
Claims (10)
1. A flight simulation system is characterized by comprising a flight dynamics unit and an automatic balancing unit;
the flight dynamics unit simulates aerodynamic parameters and engine acting force parameters of an aircraft to simulate, and resolves flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
and the automatic balancing unit is used for carrying out flight balancing on the aircraft according to the flight state parameters.
2. The flight simulation system of claim 1, wherein the flight dynamics unit includes an aerodynamic module, an engine module, and an equation of motion module;
the aerodynamic module is used for simulating atmospheric data, determining aerodynamic parameters of the aircraft according to the atmospheric data, wherein the aerodynamic parameters comprise one or a combination of the following components: resistance, lateral force, lift, roll moment, pitch moment, and yaw moment;
the engine module is used for simulating engine acting force parameters, and the engine acting force parameters comprise engine acting force and engine torque under the body coordinates provided by an engine;
the motion equation module is used for simulating a full equation of the degree of freedom dynamics of the aircraft, completing calculation of a six-degree-of-freedom rigid body motion equation of the aircraft, and calculating flight state parameters of the aircraft according to the pneumatic force parameters and the engine acting force parameters.
3. The flight simulation system of claim 2, wherein the step of the engine module simulating engine effort parameters comprises:
when the engine is started, calculating the rotating speed of a high-pressure rotor of the engine, calculating the rotating speed of a low-pressure rotor according to the rotating speed of the high-pressure rotor, and igniting and activating the engine if the rotating speed of the low-pressure rotor is judged to reach a preset ignition threshold value;
calculating the instantaneous throttle valve flow of the engine;
determining a total thrust, a ram resistance and a net thrust of the single engine from the throttle flow;
and calculating the engine acting force and the engine moment under the body coordinate according to the mounting pitch angle, the camber angle and the mounting position of the engine, the total thrust, the stamping resistance and the net thrust.
4. The flight simulation system of claim 2, wherein the flight dynamics unit further comprises a landing gear module, the landing gear module coupled to the equation of motion module;
the undercarriage module is used for calculating undercarriage acting force and undercarriage moment under an airframe coordinate provided by the undercarriage; and sending the undercarriage acting force and the undercarriage moment to the motion equation module so that the motion equation module can solve the flight state parameters of the flight simulator in the takeoff phase according to the undercarriage acting force, the undercarriage moment, the aerodynamic force parameters and the engine acting force parameters.
5. The flight simulation system of claim 4, wherein the landing gear module calculating landing gear forces and landing gear moments in body coordinates provided by the landing gear comprises:
calculating the interaction force of the wheel, the strut and the damping device under a ground coordinate system and the supporting force provided for the aircraft;
determining the friction force of the airplane wheel according to the speed, the Euler angle and the angular speed of the airplane wheel and the supporting force;
and converting the friction force into an undercarriage acting force under an airframe coordinate, and determining an undercarriage moment according to the position of the airplane wheel relative to the gravity center of the aircraft.
6. The flight simulation system of claim 3, wherein the flight dynamics unit further comprises a mass characteristics module for modeling mass changes in fuel consumption of the aircraft, and determining a mass, a center of mass, and a moment of inertia of the aircraft based on the mass changes in fuel consumption.
7. The flight simulation system of claim 1, further comprising a navigation sensing unit, an autopilot unit, and a flight control unit;
the navigation sensing unit is used for simulating positioning information of the aircraft, determining attitude information of the aircraft according to the flight state parameters, and transmitting the positioning information and the attitude information to the automatic driving unit;
the automatic pilot unit is used for simulating a flight automatic control system of the aircraft, and the flight automatic control system is used for generating automatic pilot data according to the attitude information and the positioning information; the flight automatic control system comprises a damper, a stability augmentation system, a control stability augmentation system and an automatic flight system;
the flight control unit is used for receiving the automatic driving data so as to control the aircraft to carry out unmanned flight; and receiving an operation signal, and obtaining control surface information and rod information after control law processing so as to realize manned flight of the aircraft.
8. The flight simulation system of claim 7, wherein the navigation sensing unit comprises an inertial navigation module, a global positioning module, and a flight system calculation module;
the inertial navigation module is used for determining a navigation coordinate system and determining the position and the speed of the aircraft in the navigation coordinate system according to the flight state parameters;
the global positioning module is used for determining positioning information and attitude information of the aircraft in the navigation coordinate system;
the flight system calculation module is configured to transmit the positioning information and the attitude information to the autopilot unit.
9. A flight simulation method, comprising:
simulating aerodynamic parameters and engine acting force parameters received by an aircraft during flying, and calculating flight state parameters of the aircraft under the aerodynamic parameters and the engine acting force parameters;
and carrying out flight balancing on the aircraft according to the flight state parameters.
10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the flight simulation method according to claim 9.
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