Simulation Methods and Systems for General Aviation Aircraft Control Systems

Abstract

This invention belongs to the field of aircraft teaching technology, specifically a simulation method and system for a general aviation aircraft control system, comprising the following steps: S1, setting control parameters and flight state parameters, and calculating the transmission ratio of the control mechanism and the transmission ratio of the transmission mechanism; S2, operating the control mechanism, the movement of the control mechanism is transmitted to the control surface through the transmission mechanism, and calculating the deflection angle of the control surface based on the movement distance of the control point, the transmission ratio of the control mechanism, and the transmission ratio of the transmission mechanism; S3, updating the lift coefficient based on the deflection angle, and calculating the theoretical aerodynamic force that the control surface should bear based on the lift coefficient and flight state parameters; S4, applying aerodynamic simulated loads to the control surface through the control surface loading unit, and feeding back the aerodynamic simulated loads to the control mechanism through the transmission mechanism. This invention can provide aerodynamic feedback of the control surface, improving the realism of the simulation.

Description

Technical Field

[0001] This invention belongs to the field of aircraft teaching technology, and in particular to a method and system for simulating the control system of a general aviation aircraft. Background Technology

[0002] Currently, general aviation aircraft control instruction is typically conducted in simulators. The hardware structure of existing general aviation aircraft simulators includes control mechanisms (such as control sticks and pedals), transmission mechanisms (such as cable pulley mechanisms and rocker arm transmission mechanisms), and control surfaces. The control surfaces can be elevators, rudders, or compound rudders. During instruction, the trainee operates the control mechanisms, and the movement of the control mechanisms is transmitted to the control surfaces through the transmission mechanisms, causing the control surfaces to rotate, simulating the control process of a general aviation aircraft. The control mechanisms are equipped with detection elements to detect the displacement of the operating points when the trainee operates the control mechanisms. The software of a general aviation aircraft simulator includes a parameter configuration unit and a flight status setting unit. The parameter configuration unit is used to set the parameters of the control mechanism (such as the distance L1 from the control point to the pivot point and the distance L2 from the bottom of the stick to the pivot point), the transmission parameters (such as the input arm length Lin and the output arm length Lout), and the control surface parameters (such as the control surface area S, the control surface actuation length R, and the control surface mean aerodynamic chord length D), and to calculate the control transmission ratio iA=L1 / L2 and the rocker arm transmission ratio iBn=Lin / Lout. The flight status setting unit is used to set the flight status, such as flight altitude, flight speed, and initial deflection angle of the control surfaces.

[0003] The existing simulation process involves setting the parameters of the control mechanism, transmission device, and flight status, then operating the control mechanism. The movement of the control mechanism is transmitted to the control surfaces through the transmission mechanism, causing the control surfaces to rotate, simulating the control process of a general aviation aircraft. However, because the control surfaces are not actually in flight during the simulation, they are not subject to the air resistance experienced in real flight. Therefore, there is no air resistance feedback to the control mechanism through the transmission mechanism, and trainees cannot feel the air resistance. Consequently, the simulation process is not realistic enough, affecting the teaching effect.

[0004] Chinese patent application CN202411568023.2 discloses a flight simulation model and modeling method for a variable stability flight simulator, comprising: an interface control module, a variable aerodynamic simulation module, a variable flight control simulation module, a physical characteristic simulation module, and a six-degree-of-freedom motion simulation module. The interface control module defines the external data to be received; the variable aerodynamic simulation module establishes an aerodynamic derivative interpolation table and aerodynamic coefficient expressions based on nonlinear aerodynamic data packets, and by reconstructing the aerodynamic coefficient expressions, adds the influence of externally configured aerodynamic parameters as increments to the aerodynamic coefficients; the physical characteristic simulation module outputs the aircraft weight and inertia; the six-degree-of-freedom motion simulation module calculates the aircraft's motion state; and the variable flight control simulation module constructs flight control laws under different command types, switching the corresponding control laws and control gains in real time according to the external configuration. This achieves dual adjustment of aerodynamic parameters and flight control laws within the same flight simulation model. Although the above model and its existing similar models possess variable aerodynamic simulation capabilities, the entire process runs in software and does not involve the operation and air resistance feedback of a real teaching simulator. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method and system for simulating the control system of general aviation aircraft, which can provide aerodynamic feedback of the control surfaces and improve the realism of the simulation.

[0006] To solve the above problems, the technical solution adopted by the present invention is: a general aviation aircraft control system simulation method, comprising the following steps: S1. Set the control parameters and flight status parameters, and calculate the transmission ratio of the control mechanism and the transmission ratio of the transmission mechanism. S2. Operate the control mechanism. The movement of the control mechanism is transmitted to the control surface through the transmission mechanism. Calculate the deflection angle of the control surface based on the movement distance of the control point, the transmission ratio of the control mechanism, and the transmission ratio of the transmission mechanism. S3. Update the lift coefficient based on the deflection angle, and calculate the aerodynamic force that the control surface should theoretically bear based on the lift coefficient and flight status parameters. S4. Apply aerodynamic simulation load to the control surface through the control surface loading unit. The aerodynamic simulation load is fed back to the control mechanism through the transmission mechanism.

[0007] Further, in step S1, the control transmission ratio iA is calculated based on the distance L1 from the control point to the fulcrum and the distance L2 from the bottom of the rod to the fulcrum: iA = L1 / L2; The transmission mechanism adopts a rocker arm transmission mechanism. The transmission ratio iBn of the transmission mechanism is calculated based on the input arm length Lin and the output arm length Lout of the rocker arm transmission mechanism: iBn=Lin / Lout.

[0008] Furthermore, in step S1, the flight status parameters include flight altitude, flight speed, and initial deflection angle of the control surfaces; In step S2, the formula for calculating the deflection angle at of the control surface is: at = X² / R + a₀ Where R is the actuation length of the control surface, a0 is the initial deflection angle of the control surface, and X2 is the displacement of the output rod of the rocker arm transmission mechanism, calculated according to the following formula: X2 = X1 × iBn, Where X1 is the displacement of the bottom of the control mechanism lever, calculated according to the following formula: X1 = X × iA, Where X is the distance the control point moves.

[0009] Further, in step S3, the aerodynamic force FB(t) is calculated according to the following formula: FB(t)=0.5×C(t) ×ρ×v²×S, Where C(t) is the updated lift coefficient, determined by the deflection angle α, ρ is the air density, determined by the flight altitude, v is the flight speed, and S is the control surface area.

[0010] Furthermore, in steps S1 to S4, the display unit displays the 3D diagram of the flight attitude, control parameters, flight state parameters, and aerodynamic curves.

[0011] The general aviation aircraft control system simulation system employing the above-mentioned general aviation aircraft control system simulation method includes: The parameter configuration unit is used to set the operation parameters; Flight status setting unit, used to set flight status parameters; The physical control device includes a control mechanism, a transmission mechanism, and a control surface connected in sequence; The detection unit is used to detect the movement distance of the control point of the control mechanism; The data processing unit is used to calculate the deflection angle of the control surface and the aerodynamic forces that the control surface should theoretically withstand. The control surface loading unit is used to apply aerodynamic simulation loads to the control surface.

[0012] Furthermore, it also includes a display unit for displaying a 3D diagram of flight attitude, control parameters, flight status parameters, and aerodynamic curves.

[0013] Furthermore, the control surface includes a control surface body and a rotating shaft, the rotating shaft being fixedly installed at one end of the control surface and connected to a transmission mechanism; The rudder surface loading unit includes a motor, the main shaft of which is parallel to the rotating shaft, and the motor is connected to the rotating shaft in a transmission manner.

[0014] The beneficial effects of this invention are: This invention calculates in real time the aerodynamic forces that the control surface theoretically needs to withstand under the set flight state parameters, and applies simulated aerodynamic loads to the control surface in real time according to the calculation results, so as to simulate the force state of the control surface during actual flight. The simulated aerodynamic loads are fed back to the control mechanism through the transmission mechanism, so that the trainee can feel the control resistance caused by the aerodynamic forces, thereby simulating more realistic general aviation aircraft control and improving the trainee's learning effect. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the simulation method for the control system of a general aviation aircraft according to the present invention; Figure 2 This is a schematic diagram of the general aviation aircraft control system simulation system of the present invention; Figure 3 This is a schematic diagram of the rudder surface loading unit of the present invention; Reference numerals: 1—Control mechanism; 2—Control surface; 21—Control surface body; 22—Rotating shaft; 3—Transmission mechanism; 4—Motor. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] The general aviation aircraft control system simulation system of the present invention, such as Figure 2 As shown, it includes a parameter configuration unit, a flight status setting unit, a physical control device, a detection unit, a data processing unit, and a control surface loading unit.

[0018] The physical control system comprises a control mechanism 1, a transmission mechanism 3, and control surfaces 2 connected in sequence. The control mechanism 1 is typically a control stick, pedals, etc., and the transmission mechanism 3 transmits the motion of the control mechanism 1 to the control surfaces 2. The structure of the entire physical control system simulates the relevant structure of a general aviation aircraft and is existing technology. Trainees operate the control mechanism 1 to simulate piloting a general aviation aircraft.

[0019] The parameter configuration unit is used to set the control parameters, which are the relevant parameters of the control mechanism 1, the transmission mechanism 3 and the control surface 2. For example, when the control mechanism 1 uses a control stick and the transmission mechanism 3 uses a rocker arm transmission mechanism, the control parameters may include the distance from the control point to the fulcrum, the distance from the bottom of the stick to the fulcrum, the input arm length, the output arm length, the control surface area, the control surface actuation length and the average aerodynamic chord length of the control surface, etc.

[0020] The flight status setting unit is used to set flight status parameters, which can include flight altitude, flight speed, and initial deflection angle of control surfaces, etc.

[0021] The detection unit is used to detect the movement distance of the control point of the control mechanism 1. For example, when the trainee operates the control stick, the control point is located at the top of the control stick. The control stick is usually a lever, hinged to the frame, and the hinge point is the fulcrum. The bottom of the control stick is connected to the transmission mechanism 3. When the trainee pushes the top of the control stick to move, it causes the bottom of the control stick to move, and the movement of the bottom of the control stick is transmitted to the control surface 2 through the transmission mechanism 3. By detecting the movement distance of the control point, the transmission ratio of the control mechanism 1, and the transmission ratio of the transmission mechanism 3, the deflection angle of the control surface 2 can be calculated.

[0022] The data processing unit calculates the deflection angle of control surface 2 and the theoretically required aerodynamic force. Both the detection unit and the parameter configuration unit are connected to the data processing unit. The parameter configuration unit transmits the configured control parameters and flight status parameters to the data processing unit, while the detection unit transmits the detected data to the data processing unit. The data processing unit then calculates the deflection angle of control surface 2 and the theoretically required aerodynamic force based on the configured parameters and the detected data. During the simulation, control surface 2 is not actually subjected to aerodynamic forces. However, in actual flight, control surface 2 will experience aerodynamic forces. Based on the deflection angle and flight status parameters of control surface 2, the aerodynamic forces experienced by control surface 2 during actual flight can be calculated; these aerodynamic forces are the theoretically required aerodynamic forces for control surface 2.

[0023] The control surface loading unit is connected to the data processing unit and is used to apply aerodynamic simulation loads to the control surface 2. The aerodynamic simulation load is the load that simulates aerodynamic forces. The magnitude and direction of the aerodynamic simulation load should be as close as possible to the magnitude and direction of the calculated aerodynamic forces.

[0024] The control surface loading unit can employ a hydraulic cylinder. The hydraulic cylinder connects to a sheet metal plate, which is then in contact with the control surface 2. The hydraulic cylinder applies tension or thrust to the sheet metal plate, which then transmits the tension or thrust to the control surface 2 to simulate the aerodynamic forces borne by the control surface 2. However, since the control surface 2 is a thin plate with a large area, and it deflects at various angles during the simulation, the load application mechanism, such as the hydraulic cylinder, must be dynamically configured. That is, its position must change as the control surface 2 deflects to ensure that the direction of the load is perpendicular to the control surface 2, which presents a high implementation challenge.

[0025] In existing physical control devices, the control surface 2 includes a control surface body 21 and a rotating shaft 22. The rotating shaft 22 is fixedly installed at one end of the control surface 2 and rotates with the frame to ensure that the entire control surface 2 can deflect. The rotating shaft 22 is also connected to a transmission mechanism 3, which drives the rotating shaft 22 to rotate. In this invention, to facilitate the addition of a control surface loading unit to the existing physical control device, the control surface loading unit includes a motor 4, such as... Figure 3As shown, the main shaft of motor 4 is parallel to the rotating shaft 22, and motor 4 is connected to rotating shaft 22 via a transmission connection. Motor 4 is a torque motor, specifically connected to rotating shaft 22 via a gear transmission connection. When the control surface body 21 bears aerodynamic force, the load transmitted to rotating shaft 22 is mainly torque. Therefore, the torque of rotating shaft 22 is calculated based on the magnitude of the aerodynamic force, and then motor 4 is controlled to apply the corresponding torque to rotating shaft 22.

[0026] In addition, the present invention includes a display unit for displaying a 3D diagram of flight attitude, control parameters, flight status parameters, and aerodynamic curves. The display unit is located in front of the pilot's seat, allowing the trainee to view various data while operating the control mechanism 1.

[0027] The general aviation aircraft control system simulation method of the present invention, such as Figure 1 As shown, the specific steps include: S1. Set the control parameters and flight status parameters, and calculate the transmission ratio of control mechanism 1 and transmission ratio of transmission mechanism 3.

[0028] Specifically, flight status parameters include flight altitude, flight speed, and initial deflection angle of control surfaces.

[0029] Control parameters may include the distance L1 from the control point to the fulcrum, the distance L2 from the bottom of the stick to the fulcrum, the input arm length Lin, the output arm length Lout, the control surface area S, the control surface actuation length R, and the average aerodynamic chord length D of the control surface, etc.

[0030] The control transmission ratio iA is calculated based on the distance L1 from the control point to the fulcrum and the distance L2 from the bottom of the rod to the fulcrum: iA = L1 / L2; Transmission mechanism 3 adopts a rocker arm transmission mechanism. The transmission ratio iBn of transmission mechanism 3 is calculated based on the input arm length Lin and the output arm length Lout: iBn = Lin / Lout. A rocker arm transmission mechanism typically includes multiple sub-rocker arm mechanisms, each with its own input and output arm lengths. Therefore, the transmission ratio of each sub-rocker arm mechanism is calculated first, and then the transmission ratios of all sub-rocker arm mechanisms are multiplied together to obtain the transmission ratio iBn of the entire rocker arm transmission mechanism.

[0031] S2. Operate the control mechanism 1. The movement of the control mechanism 1 is transmitted to the control surface 2 through the transmission mechanism 3. Calculate the deflection angle of the control surface 2 based on the movement distance of the control point, the transmission ratio of the control mechanism 1, and the transmission ratio of the transmission mechanism 3.

[0032] The trainee operates control mechanism 1 to simulate the operation of piloting a general aviation aircraft. When control mechanism 1 is a control stick, the trainee pushes the control stick with their hand to move it; when control mechanism 1 is a foot pedal, the trainee steps on the foot pedal to make the foot pedal move.

[0033] The formula for calculating the deflection angle at of rudder surface 2 is as follows: at = X² / R + a₀ Where R is the actuating length of the control surface, a0 is the initial deflection angle of the control surface, and the sum of the initial deflection angle and the angle at which the transmission mechanism drives the control surface 2 to deflect is the real-time deflection angle of the control surface 2. X2 is the displacement of the output rod of the rocker arm transmission mechanism, calculated according to the following formula: X2 = X1 × iBn, Where X1 is the displacement of the bottom of the control mechanism lever, calculated according to the following formula: X1 = X × iA, Where X represents the distance the control point moves. When the control mechanism 1 is a joystick, the control point is located at the top of the joystick, and the bottom of the joystick is connected to the transmission mechanism 3.

[0034] S3. Update the lift coefficient based on the deflection angle, and calculate the theoretical aerodynamic force that the control surface 2 should bear based on the lift coefficient and flight state parameters.

[0035] When the control surface 2 is at the initial deflection angle, it has an initial lift coefficient. When the transmission mechanism 3 drives the control surface 2 to continue to deflect, the deflection angle of the control surface 2 changes, and the lift coefficient also changes. Therefore, the lift coefficient needs to be updated according to the real-time deflection angle of the control surface 2.

[0036] Specifically, a table showing the correspondence between control surface deflection angle and lift coefficient can be generated using general aviation aircraft control surface aerodynamic manuals, wind tunnel test data, or simplified aerodynamic model calculations, as shown in the table below:

[0037] Based on the deflection angle of the control surfaces, the corresponding lift coefficient can be determined.

[0038] The aerodynamic force FB(t) is calculated according to the following formula: FB(t)=0.5×C(t) ×ρ×v²×S, Where C(t) is the updated lift coefficient, determined by the deflection angle α, ρ is the air density, determined by the flight altitude, v is the flight speed, and S is the control surface area.

[0039] S4. Apply aerodynamic simulation load to the control surface 2 through the control surface loading unit. The aerodynamic simulation load is fed back to the control mechanism 1 through the transmission mechanism 3.

[0040] During the above process, the display unit shows a 3D diagram of the flight attitude, control parameters, flight status parameters, and aerodynamic curves. This transforms abstract theoretical knowledge such as control displacement transmission, aerodynamic calculation, and force feedback generation into visualized mechanical motion and data curves. Trainees can directly operate the control stick and pedals while observing real-time changes in control surface deflection angles, lift coefficients, and aerodynamic forces, understanding the impact of transmission ratios and aerodynamic characteristics on control feel. This addresses the pain point of the disconnect between theory and practice in traditional teaching.

[0041] This invention calculates in real time the aerodynamic forces that the control surface 2 theoretically needs to withstand under set flight parameters, and applies simulated aerodynamic loads to the control surface 2 in real time based on the calculation results to simulate the force state of the control surface 2 during actual flight. The simulated aerodynamic loads are fed back to the control mechanism 1 through the transmission mechanism 3, so that the trainee can feel the control resistance caused by the aerodynamic forces, thereby simulating more realistic general aviation aircraft control and improving the trainee's learning effect.

[0042] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for simulating the control system of a general aviation aircraft, characterized in that, Includes the following steps: S1. Set the control parameters and flight status parameters, and calculate the transmission ratio of the control mechanism (1) and the transmission ratio of the transmission mechanism (3); S2. Operate the control mechanism (1). The movement of the control mechanism (1) is transmitted to the rudder surface (2) through the transmission mechanism (3). Calculate the deflection angle of the rudder surface (2) based on the movement distance of the control point, the transmission ratio of the control mechanism (1) and the transmission ratio of the transmission mechanism (3). S3. Update the lift coefficient according to the deflection angle, and calculate the aerodynamic force that the control surface (2) should theoretically bear according to the lift coefficient and flight state parameters. S4. Apply aerodynamic simulation load to the control surface (2) through the control surface loading unit. The aerodynamic simulation load is fed back to the control mechanism (1) through the transmission mechanism (3).

2. The general aviation aircraft control system simulation method as described in claim 1, characterized in that, In step S1, the control transmission ratio i is calculated based on the distance L1 from the control point to the fulcrum and the distance L2 from the bottom of the rod to the fulcrum. A :i A =L1 / L2; The transmission mechanism (3) adopts a rocker arm transmission mechanism, and the transmission ratio i of the transmission mechanism (3) is calculated according to the input arm length Lin and the output arm length Lout of the rocker arm transmission mechanism Bn : i Bn = Lin / Lout.

3. The general aviation aircraft control system simulation method as described in claim 2, characterized in that, In step S1, the flight status parameters include flight altitude, flight speed, and initial deflection angle of the control surfaces; In step S2, the deflection angle a of the control surface (2) t The calculation formula is: a t =X2 / R+a0, Where R is the actuation length of the control surface, a0 is the initial deflection angle of the control surface, and X2 is the displacement of the output rod of the rocker arm transmission mechanism, calculated according to the following formula: X2 = X1 × i Bn , Where X1 is the displacement of the bottom of the control mechanism lever, calculated according to the following formula: X1=X×i A , Where X is the distance the control point moves.

4. The general aviation aircraft control system simulation method as described in claim 3, characterized in that, In step S3, the aerodynamic force FB(t) is calculated according to the following formula: FB(t)=0.5×C(t) ×ρ×v²×S, Where C(t) is the updated lift coefficient, determined by the deflection angle α, ρ is the air density, determined by the flight altitude, v is the flight speed, and S is the control surface area.

5. The general aviation aircraft control system simulation method as described in claim 1, characterized in that, In steps S1 to S4, the display unit displays the 3D diagram of flight attitude, control parameters, flight state parameters, and aerodynamic curves.

6. A general aviation aircraft control system simulation system employing the general aviation aircraft control system simulation method of claim 1, characterized in that, include The parameter configuration unit is used to set the operating parameters; Flight status setting unit, used to set flight status parameters; The physical control device includes a control mechanism (1), a transmission mechanism (3), and a control surface (2) connected in sequence. The detection unit is used to detect the movement distance of the control point of the control mechanism (1); The data processing unit is used to calculate the deflection angle of the control surface (2) and the aerodynamic force that the control surface (2) is theoretically required to withstand. The control surface loading unit is used to apply aerodynamic simulation loads to the control surface (2).

7. The general aviation aircraft control system simulation system as described in claim 6, characterized in that, It also includes a display unit for displaying 3D flight attitude diagrams, control parameters, flight status parameters, and aerodynamic curves.

8. The general aviation aircraft control system simulation system as described in claim 6, characterized in that, The rudder surface (2) includes a rudder surface body (21) and a rotating shaft (22). The rotating shaft (22) is fixedly installed at one end of the rudder surface (2) and is connected to the transmission mechanism (3). The rudder surface loading unit includes a motor (4), the main shaft of the motor (4) is parallel to the rotating shaft (22), and the motor (4) is connected to the rotating shaft (22) in a transmission connection.

Images