High-speed aircraft trajectory planning method based on active flow control multivariable coupling

Abstract

The invention discloses a high-speed aircraft trajectory planning method and device based on active flow control multivariable coupling, a medium and equipment, and the method comprises the steps: obtaining a first group of correlation coefficients of an aircraft affected by a jet flow, and obtaining a second group of correlation coefficients of the aircraft not affected by the jet flow; replacing the second group of correlation coefficients with the first group of correlation coefficients to obtain a new kinematic equation and a new kinetic equation; determining an aircraft trajectory planning model based on the active flow control system based on the control quantity, the constraint condition, the target function, the new kinetic equation and the new kinematical equation; the aircraft trajectory planning model based on the active flow control system is solved, the target planning trajectory of the aircraft is obtained, the trajectory planning flexibility and efficiency are improved, the controllability and stability of the aircraft in a complex environment are enhanced, and the aircraft trajectory planning method and device are suitable for large-scale popularization and application. Therefore, the trajectory planning system can more intelligently respond to various dynamic changes in the flight process, so that the smooth completion of the flight task is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft guidance and control, and in particular to a high-speed aircraft trajectory planning method, device, medium and equipment based on active flow control multivariable coupling. Background Art

[0002] Hypersonic vehicles have important application backgrounds in the fields of space return, long-range rapid strike, etc. Due to its own aerodynamic layout and the influence of harsh flight environment, the dynamic model of hypersonic vehicles has the characteristics of high nonlinearity, strong coupling and parameter uncertainty. In addition, the aircraft faces complex flight constraints such as dynamic pressure, heat flow, and overload, which makes the aircraft trajectory planning problem very complicated. Therefore, the problem of aircraft trajectory optimization has always been a key and difficult point in the field of aerospace engineering. With the development of aerospace technology, strong adaptability, rapid response and high reliability have become the goals to be pursued.

[0003] The essence of trajectory planning is to solve a performance index and multiple continuous-time optimal control problems with constraints on state quantities and control quantities. Common performance indicators include minimizing fuel consumption, shortest reentry time, minimum total heat load, or maximizing range and speed. Constraints generally include equations of motion, necessary safety constraints such as dynamic pressure, heat flow, overload, etc., as well as terminal target state constraints.

[0004] In existing aircraft trajectory planning methods, the control variables are usually the aircraft's thrust, angle of attack, sideslip angle, and roll angle, and their constraint boundaries are set as fixed parameters; and they are mostly based on idealized flight parameters and environmental conditions, only considering the impact of airflow angles such as angle of attack on aerodynamics. Summary of the invention

[0005] The main purpose of the present application is to provide a high-speed aircraft trajectory planning method, device, medium and equipment based on active flow control multivariable coupling, aiming to improve the environmental adaptability and flight performance of the aircraft.

[0006] To achieve the above-mentioned purpose, the present application provides a high-speed aircraft trajectory planning method based on active flow control multivariable coupling, including: respectively obtaining a first set of correlation coefficients of the aircraft affected by the jet, the first set of correlation coefficients including a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control; obtaining a second set of correlation coefficients of the aircraft not affected by the jet, the second set of correlation coefficients including a second lift coefficient expression, a second drag coefficient expression and a second pitch moment coefficient expression, replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain new kinematic equations and new dynamic equations; determining an aircraft trajectory planning model based on an active flow control system based on pre-constructed control quantities, constraints and objective functions during the flight of the aircraft, the new dynamic equations and the new kinematic equations; solving the aircraft trajectory planning model based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain a target planning trajectory of the aircraft.

[0007] Optionally, the expression of the first lift coefficient includes:

[0008] C L =C L _a+C L _PSJ

[0009] C L =f(Ma,α,p)

[0010] Where Ma is the Mach number, α is the angle of attack, p is the jet flow of the active flow actuator, CL_a is a function of Ma and α, C L _PSJ are functions of Ma, α and p, C L represents the lift coefficient;

[0011] The expression of the first drag coefficient includes:

[0012] C D =C D _a+C D _PSJ

[0013] C D =f(Ma,α,p)

[0014] Where Ma is the Mach number, α is the angle of attack, p is the jet flow rate of the active flow actuator, and C is D _a is a function of Mach number Ma and angle of attack α, C L _PSJ is a function of Mach number Ma, angle of attack α and jet flow rate p, C D represents the drag coefficient;

[0015] The expression of the first pitching moment coefficient includes:

[0016] C M =C M _a+C M _PSJ

[0017] C M =f M (Ma,α,p)

[0018] Where Ma is the Mach number, α is the angle of attack, p is the jet flow rate of the active flow actuator, and C is M _a is a function of Mach number Ma and angle of attack α, C M _PSJ is a function of Mach number Ma, angle of attack α and jet flow rate p, C M represents the pitching moment coefficient.

[0019] Optionally, the state constraints include control quantity constraints, process constraints, initial constraints and terminal constraints.

[0020] Optionally, the control quantity includes the second-order derivative of the angle of attack, the second-order derivative of the roll angle and the jet flow rate; the expression of the control quantity constraint is:

[0021]

[0022] Where Mz represents the pitch moment, Mz = 0.5C M ρV 2 SL, p max They represent the minimum second-order derivative of the roll angle, the maximum second-order derivative of the roll angle and the maximum jet flow rate, respectively. K1 represents the control quantity constraint. f represents the functional expression of the second-order derivative of the angle of attack and the pitching moment. Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, and K1 represents the control quantity constraint.

[0023] Optionally, the expression of the process constraint is:

[0024]

[0025] Among them, k Q is the heat flow rate calculation coefficient, g0 represents the sea level gravity acceleration, q max , n max , D min and T maxThey are the maximum dynamic pressure, maximum heat flux, maximum overload, minimum drag acceleration, and maximum total jet volume, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H represents the atmospheric density scale, V represents the flight speed of the aircraft, L and D represent the lift acceleration and drag acceleration of the aircraft, respectively, and D min and T max They represent the minimum resistance acceleration and the maximum jet volume respectively, T represents the jet volume, and K2 represents the process constraint.

[0026] Optionally, the initial constraint expression is:

[0027]

[0028] Among them, represents the initial time t0, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, S represents the initial constraint;

[0029] The expression of the terminal constraint is:

[0030]

[0031] Among them, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, and Φ represents the terminal constraint.

[0032] 7. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling according to claim 1, characterized in that the expression of the aircraft trajectory planning model based on the active flow control system is:

[0033] P0:

[0034] min J=-x x

[0035] st

[0036]

[0037] Wherein, f1 represents the state differential equation, K1 represents the control quantity constraint, K2 represents the process constraint, S represents the initial constraint, Φ represents the terminal constraint, J represents the objective function, P0 represents the optimal control problem, r represents the distance from the center of the earth of the aircraft, V represents the flight speed of the aircraft, θ represents the longitude, φ represents the latitude, γ represents the track angle, ψ represents the heading angle, L and D represent the lift acceleration and drag acceleration of the aircraft respectively, Ω represents the angular velocity of the earth's rotation, σ represents the roll angle, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H represents the atmospheric density scale height, m ​​represents the mass of the aircraft, Ω represents the angular velocity of the earth's rotation, and t0 represents the initial time. Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, g0 represents the gravitational acceleration at sea level, q max , n max , D min and T max They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum drag acceleration and maximum jet volume, q, and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively, t f Indicates the flight time, D min Indicates the minimum drag acceleration of the aircraft, k Q represents the heat flow rate calculation coefficient, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, is the aircraft terminal velocity, represents the second-order derivative of the angle of attack, represents the second-order derivative of the roll angle, represents the maximum value of the second-order inverse of the roll angle, represents the minimum value of the second-order inverse of the roll angle, f represents the functional expression of the second-order derivative of the angle of attack and the pitch moment, p represents the aircraft jet flow rate, T represents the total amount of jet, Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, x x Indicates the displacement in the direction of the finger.

[0038] To achieve the above-mentioned purpose, the present application also provides a high-speed aircraft trajectory planning device based on active flow control multivariable coupling, including: an acquisition module, used to respectively acquire a first group of correlation coefficients of the aircraft affected by the jet, the first group of correlation coefficients including a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control; a model pre-construction module, used to acquire a second group of correlation coefficients of the aircraft not affected by the jet, the second group of correlation coefficients including a second lift coefficient expression, a second drag coefficient expression and a second pitch moment coefficient expression, and the first group of correlation coefficients are used to replace the second group of correlation coefficients to obtain new kinematic equations and new dynamic equations; a model determination module, used to determine an aircraft trajectory planning model based on an active flow control system based on the pre-constructed control quantity, constraint conditions and objective function during the flight of the aircraft, the new dynamic equations and the new kinematic equations; a trajectory solving module, used to solve the aircraft trajectory planning model based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain the target planning trajectory of the aircraft.

[0039] To achieve the above objectives, the present application also provides a computer-readable storage medium, which includes instructions, which, when executed on a computer, enables the computer to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in the above embodiment.

[0040] To achieve the above-mentioned purpose, the present application also provides an electronic device, which includes: at least one processor, a memory and an input-output unit; wherein the memory is used to store computer programs, and the processor is used to call the computer program stored in the memory to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in any of the aforementioned embodiments.

[0041] The embodiment of the present application proposes a high-speed aircraft trajectory planning method, device, medium and equipment based on active flow control multivariable coupling, by respectively obtaining a first group of correlation coefficients of the aircraft affected by the jet, the first group of correlation coefficients including a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet effect on the aircraft is generated based on active flow control; obtaining a second group of correlation coefficients of the aircraft not affected by the jet, the second group of correlation coefficients including a second lift coefficient expression, a second drag coefficient expression and a second pitch moment coefficient expression, and replacing the second group of correlation coefficients with the first group of correlation coefficients to obtain New kinematic equations and new dynamic equations; determine the aircraft trajectory planning model based on the active flow control system based on the pre-built control quantities, constraints and objective functions during the aircraft flight process, the new dynamic equations and the new kinematic equations; solve the aircraft trajectory planning model based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain the target planning trajectory of the aircraft, which improves the flexibility and efficiency of trajectory planning, and also enhances the controllability and stability of the aircraft in complex environments, so that the trajectory planning system can respond more intelligently to various dynamic changes during the flight process, thereby ensuring the smooth completion of the flight mission. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A flow chart of an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in this application;

[0043] Figure 2 A schematic diagram of the installation position of the flow controller provided in an embodiment of the high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application;

[0044] FIG3 is a curve showing the lift coefficient changing with the angle of attack and the jet flow rate provided by an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application, wherein FIG3(a) is a curve showing the lift coefficient changing with the angle of attack and the jet flow rate at 1.2 Ma, FIG3(b) is a curve showing the lift coefficient changing with the angle of attack and the jet flow rate at 10 Ma, and FIG3(c) is a curve showing the lift coefficient changing with the angle of attack and the jet flow rate at 15 Ma;

[0045] FIG4 is a curve showing the change of the drag coefficient with the angle of attack and the jet flow rate provided by an embodiment of the high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application, wherein FIG4(a) is a curve showing the change of the drag coefficient with the angle of attack and the jet flow rate at 1.2 Ma, FIG4(b) is a curve showing the change of the drag coefficient with the angle of attack and the jet flow rate at 10 Ma, and FIG4(c) is a curve showing the change of the drag coefficient with the angle of attack and the jet flow rate at 15 Ma;

[0046] FIG5 is a curve showing the pitch moment coefficient changing with the angle of attack provided by an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application, wherein FIG5(a) is a curve showing the pitch moment coefficient changing with the angle of attack and the jet flow rate at 1.2 Ma, FIG5(b) is a curve showing the pitch moment coefficient changing with the angle of attack and the jet flow rate at 10 Ma, and FIG5(c) is a curve showing the pitch moment coefficient changing with the angle of attack and the jet flow rate at 15 Ma;

[0047] Figure 6 A simulation diagram of the change of flight altitude with flight distance provided for an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application;

[0048] Figure 7 A simulation diagram of the change of jet flow rate with flight distance provided in an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling of the present application;

[0049] Figure 8 A block diagram of the device structure provided for an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling in this application.

[0050] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0052] In the prior art, there are many methods involved in the problem of aircraft trajectory planning. The indirect method and the direct method are the most commonly used methods, and they are also the two basic solution frameworks for the trajectory planning problem. The indirect method framework is based on the minimum principle and converts the entire aircraft trajectory planning problem into a two-point boundary value problem for solution. The direct method framework does not require the derivation of the optimal control equation and directly uses a nonlinear optimization algorithm to solve the optimal control problem.

[0053] Reference Figure 1 The first embodiment of the present application provides a high-speed aircraft trajectory planning method based on active flow control multivariable coupling, which may include:

[0054] S10, respectively obtaining a first set of correlation coefficients of the aircraft affected by the jet, the first set of correlation coefficients comprising a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control;

[0055] Before step S10 , the high-speed aircraft trajectory planning method based on active flow control multivariable coupling further includes step S00 .

[0056] Arrange the flow controller at the head position, such as Figure 2 As shown in Figure 2, the influence of active flow control system on the lift characteristics of aircraft is analyzed. Active flow control system can stimulate additional airflow on the surface of aircraft, effectively delay or suppress airflow separation, and thus change the lift coefficient, such as Figure 3(a)-Figure 3(c) As shown, in Figure 3(a)-Figure 3(c) The study simulated the changes of lift coefficient of aircraft with angle of attack and jet flow rate at different Mach numbers. Figure 4(a)-Figure 4(c) The paper simulates and studies the changes of the aircraft's drag coefficient with the angle of attack and jet flow at different Mach numbers to analyze the influence of the active flow control system on the aircraft's drag characteristics. The active flow control system can stimulate additional airflow on the aircraft's surface, which can effectively delay or suppress the airflow separation phenomenon and reduce the additional drag caused by separation; analyze the influence of the active flow control system on the aircraft's pitch control torque. The active flow control system can stimulate additional airflow on the aircraft's surface, which can change the aircraft's lift action point, thereby changing the pitch control torque, such as Figure 5(a)-Figure 5(c) As shown, Figure 5(a)-Figure 5(c) The simulation studies the change of the pitch moment coefficient of the aircraft with the angle of attack and the jet flow rate at different Mach numbers. Through the above analysis process, it can be known that the active flow control system can stimulate additional airflow on the surface of the aircraft, change the lift point of the aircraft, and thus change the pitch control moment. Taking the waverider shape as an example, the flow controller is arranged at the head position.

[0057] The flow controller can control the flow rate of the jet, so the aircraft dynamics model considering flow control needs to use the flow controller as an additional control mechanism to change the aircraft attitude and ultimately change the aerodynamic force.

[0058] Without considering the rudder deflection, the above analysis shows that the lift coefficient is mainly affected by the angle of attack, Mach number and jet flow rate, so the lift coefficient expression C L Can be:

[0059] C L =C L _a+C L _PSJ

[0060] C L =f(Ma,α,p)

[0061] Where Ma represents the Mach number, α represents the angle of attack, and δ represents the jet flow of the active flow actuator. L _a is a function of Mach number and angle of attack, C L _PSJ is a function of Ma, α and p.

[0062] Similarly, the drag coefficient expression CD Can be:

[0063] C D =C D _a+C D _PSJ

[0064] C D =f(Ma,α,p)

[0065] Among them, C D _a is also a function of Mach number and angle of attack, C D _PSJ is also a function of Ma, α and p.

[0066] Similarly, the pitch moment coefficient C M It can be expressed as:

[0067] C M =C M _a+C M _PSJ

[0068] C M =f M (Ma,α,p)

[0069] Where Ma represents the Mach number, α represents the angle of attack, and δ represents the jet flow rate of the active flow actuator. M _a is a function of Mach number Ma and angle of attack α, C M _PSJ is a function of the Mach number Ma, the angle of attack α and the jet flow rate p.

[0070] S20, obtaining a second set of correlation coefficients for the aircraft that is not affected by the jet, the second set of correlation coefficients comprising a second lift coefficient expression, a second drag coefficient expression, and a second pitch moment coefficient expression, and replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain a new kinematic equation and a new dynamic equation;

[0071] In an embodiment of the present application, step S20 may include the following execution process:

[0072] First, establish the dynamic equation of the center of mass motion of the aircraft:

[0073]

[0074] In the formula, α represents the angle of attack, σ represents the roll angle, P represents the thrust, and L = 0.5C L ρV 2 S / m, D = 0.5C D ρV 2 S / m, L and D represent the lift acceleration and drag acceleration of the aircraft respectively, μ represents the earth's gravitational constant, C L , CD They represent the lift coefficient and drag coefficient respectively, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H=7110m represents the atmospheric density scale, S represents the reference area of ​​the aircraft, m represents the mass of the aircraft, and Ω represents the angular velocity of the earth's rotation.

[0075] Secondly, ignoring the influence of the earth's curvature and wind, the aircraft motion equation is established in the ballistic coordinate system according to Newton's kinematic equation:

[0076]

[0077] Where r is the distance from the center of the earth to the aircraft, V is the speed, θ is the longitude, φ is the latitude, γ is the track angle, and ψ is the heading angle.

[0078] Finally, the first lift coefficient expression, the first drag coefficient expression and the first pitch moment coefficient expression obtained in step S10 are used to replace the second lift coefficient expression, the second drag coefficient expression and the second pitch moment coefficient expression in the dynamic equation accordingly to obtain new kinematic equations and new dynamic equations.

[0079] S30, determining an aircraft trajectory planning model based on an active flow control system based on the pre-constructed control quantity, constraint conditions and objective function during the flight of the aircraft, the new dynamic equations and the new kinematic equations;

[0080] In an embodiment of the present application, step S30 may include the following execution process:

[0081] S301, setting the control quantity, control quantity constraint, initial constraint, terminal constraint, process constraint and objective function during the flight of the aircraft;

[0082] Among them, the control quantities of traditional aircraft trajectory planning are the angle of attack α and the roll angle σ. After the introduction of active flow control, the control quantity u takes the second-order derivative of the aircraft angle of attack: Second derivative of the roll angle and the aircraft jet flow, The second derivative of the angle of attack Second derivative of the roll angle As a control quantity, the control can be made more precise. Using the jet flow rate as a control quantity can adapt to airflow changes in real time and maintain optimal flight performance. This technology has not yet been applied in existing trajectory planning.

[0083] Set the control quantity constraint:

[0084] Under the action of the active flow control system, the second-order derivative of the angle of attack Affected by the second derivative of the pitch angle The direct impact of The size of is closely related to the pitching moment, and the jet flow rate is an important factor affecting the pitching moment boundary. The boundary of also depends on the jet flow rate. At the same time, considering the physical characteristics of the jet device and the limitations of flight performance, the second-order derivative of the jet flow rate p and the roll angle is also bounded, and the definitions of the above three control constraints are expressed as follows:

[0085]

[0086] Where Mz represents the pitch moment, Mz = 0.5C M ρV 2 SL, p max They are the minimum second-order derivative of the roll angle, the maximum second-order derivative of the roll angle and the maximum jet flow rate, respectively.

[0087] Set the initial constraints:

[0088] The initial state of the aircraft is usually known, denoted by S:

[0089]

[0090] Among them, represents the initial time t0, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, Indicates the initial quality.

[0091] To set terminal constraints:

[0092] Terminal state constraint Φ:

[0093]

[0094] Among them, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, Indicates the terminal velocity of the aircraft.

[0095] Set process constraints:

[0096] In order to ensure the structural safety of the aircraft, trajectory planning generally needs to consider the process constraints of heat flow Dynamic pressure q and total overload n, these three parameters cannot exceed the given maximum value during the flight. At the same time, in order to ensure that the glider has sufficient aerodynamic force to achieve trajectory control, the drag acceleration D must have a minimum boundary. Due to the installation of active flow control devices, the maximum total amount of jet T carried by the aircraft cannot exceed the given maximum value. The definitions of the above five process constraints are set as follows:

[0097]

[0098] Among them, k Q is the heat flow rate calculation coefficient, g0 is the sea level gravity acceleration, q max , n max , D min and T max They are maximum dynamic pressure, maximum heat flux, maximum overload, minimum resistance acceleration, and maximum total jet volume.

[0099] Set the objective function:

[0100] The performance indicators of the aircraft trajectory planning problem can be determined according to different flight missions, usually including maximum terminal velocity, maximum flight range, etc. In order to verify the superiority of the trajectory planning method using active flow control system over the traditional method, the maximum range of the aircraft is taken as the objective function, where x x Refers to the displacement in the direction of projection:

[0101] min J=-x x

[0102] S301. Constructing a vehicle trajectory planning model based on flow control

[0103] The trajectory optimization model is described as an optimal control problem P0 including the state differential equation f1, the control quantity constraint K1, the process constraint K2, the initial constraint S, the terminal constraint Φ and the objective function J; where,

[0104] P0:

[0105] min J=-x x

[0106] st

[0107]

[0108] In the formula, f1 represents the state differential equation, K1 represents the control quantity constraint, K2 represents the process constraint, S represents the initial constraint, Φ represents the terminal constraint, J represents the objective function, P0 represents the optimal control problem, r represents the distance from the center of the earth of the aircraft, V represents the flight speed of the aircraft, θ represents the longitude, φ represents the latitude, γ represents the track angle, ψ represents the heading angle, L and D represent the lift acceleration and drag acceleration of the aircraft respectively, Ω represents the angular velocity of the earth's rotation, σ represents the roll angle, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H represents the atmospheric density scale height, m ​​represents the mass of the aircraft, Ω represents the angular velocity of the earth's rotation, and t0 represents the initial time. Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, g0 represents the gravitational acceleration at sea level, q max , n max , D min and T max They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum drag acceleration and maximum jet volume, q, and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively, t f Indicates the flight time, D min Indicates the minimum drag acceleration of the aircraft, k Q represents the heat flow rate calculation coefficient, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, is the aircraft terminal velocity, represents the second-order derivative of the angle of attack, represents the second-order derivative of the roll angle, represents the maximum value of the second-order inverse of the roll angle, represents the minimum value of the second-order inverse of the roll angle, f represents the functional expression of the second-order derivative of the angle of attack and the pitch moment, p represents the aircraft jet flow rate, T represents the total amount of jet, Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, x x Indicates the displacement in the direction of the finger.

[0109] S40, solving the aircraft trajectory planning model based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain the planned trajectory of the aircraft.

[0110] Specifically, step S40 may include the following execution process:

[0111] S401, initialize the grid interval, set the number of iterations M = 0, set the initial division of the interval and the upper and lower limits N of the number of points in the interval min ,N max ; Set the total number of intervals of the aircraft trajectory to K, the current interval to k, {k|1≤k≤K}, the initial number of points in each interval to N, N…1, the error threshold to ε, and the relative curvature threshold to r max ;

[0112] S402, using Radau pseudospectral method to discretize the trajectory planning problem, transform it into an NLP problem for solution, and calculate the relative maximum error e of the solution. max ; Discretize the optimal control problem into an NLP problem at the points in each interval and solve it to obtain the state variable value x(τ) and control variable value u(τ) corresponding to a flight trajectory; Calculate the maximum residual of each interval through the state variable value x(τ) and control variable value u(τ)

[0113] S403, if all intervals of e max All less than ε or N>N max , stop iteration; otherwise, continue to S405;

[0114] according to and ε, determine whether the flight trajectory obtained in step S402 is the optimal trajectory. The flight trajectory obtained in step S402 is the optimal trajectory, and the optimization is completed. Calculate the relative curvature of these intervals And execute step S405;

[0115] S404, in e max >ε, the grid is updated using an adaptive strategy until all grids are updated; and r max If Then use the following formula to redetermine the number of points N in the corresponding interval: k ;

[0116]

[0117] in, For the ceiling function, the positive integer A is an adjustable factor.

[0118] like Then use the following formula to redivide the corresponding interval into n ksubintervals, and set the number of points in each subinterval to

[0119]

[0120] Among them, the positive integer B is an adjustable factor.

[0121] The new number and distribution of the points in these intervals are obtained, and then step S402 is executed to perform the next iteration.

[0122] S405, let N=N+1, and go to step S402 for the next iteration.

[0123] S50: Output the path planning result.

[0124] A simulation example is provided below to illustrate this application:

[0125] The planning simulation of the aircraft glide trajectory with and without jet flow was carried out, and the results are as follows:

[0126] The initial altitude of the aircraft is 70km, the initial speed is 25Ma, the mass is 900kg, the terminal altitude is 30km, the terminal minimum speed is 8Ma, and the flight trajectory is planned with the longest range as the planning indicator, with or without jets. When there is a jet, the maximum jet flow rate is 50g / s, and the maximum jet is 50kg. The flight altitude and jet flow rate change with the flight distance as shown in the figure below: Figure 6 and Figure 7 The simulation calculation shows that without the jet assistance, the maximum flight distance of the aircraft is 18308km. After using the active flow control device to increase the jet, the maximum flight distance of the aircraft is increased to 19319km. It can be seen that the jet assistance significantly increases the range of the aircraft, with a specific increase of 1008km.

[0127] refer to Figure 8On the basis of the above embodiments, the present application further proposes a high-speed aircraft trajectory planning device based on active flow control multivariable coupling, and the high-speed aircraft trajectory planning device based on active flow control multivariable coupling 100 includes an acquisition module 1001, a model pre-construction module, a model determination module 1003 and a trajectory solution module 1004, wherein the acquisition module 1001 is used to respectively obtain a first group of correlation coefficients of the aircraft affected by the jet, the first group of correlation coefficients includes a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet effect on the aircraft is generated based on active flow control; the model pre-construction module 1002 is used to obtain the aircraft not affected by the jet The second group of correlation coefficients includes a second lift coefficient expression, a second drag coefficient expression, and a second pitch moment coefficient expression. The first group of correlation coefficients are used to replace the second group of correlation coefficients to obtain new kinematic equations and new dynamic equations; the model determination module 1003 is used to determine the trajectory planning model of the aircraft based on the active flow control system based on the pre-built control quantity, constraint conditions and objective function during the flight of the aircraft, the new dynamic equations and the new kinematic equations; the trajectory solving module 1004 is used to solve the trajectory planning model of the aircraft based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain the target planning trajectory of the aircraft. .

[0128] Based on the above embodiments, the present application also provides a computer-readable storage medium, which includes instructions, which, when executed on a computer, enables the computer to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in any of the above embodiments.

[0129] Based on the above embodiments, the present application also provides an electronic device, which includes: at least one processor, a memory and an input-output unit; wherein the memory is used to store computer programs, and the processor is used to call the computer programs stored in the memory to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in any of the above embodiments.

[0130] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A high-speed aircraft trajectory planning method based on active flow control multivariable coupling, characterized in that: include: Respectively obtaining a first set of correlation coefficients of the aircraft affected by the jet, the first set of correlation coefficients comprising a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control; Obtaining a second set of correlation coefficients of the aircraft that is not affected by the jet, the second set of correlation coefficients comprising a second lift coefficient expression, a second drag coefficient expression, and a second pitch moment coefficient expression, and replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain a new kinematic equation and a new dynamic equation; Determine a trajectory planning model for an aircraft based on an active flow control system based on the pre-constructed control variables, constraints and objective functions during the flight of the aircraft, the new dynamic equations and the new kinematic equations; The aircraft trajectory planning model based on the active flow control system is solved based on the hp adaptive Radau pseudo-spectral algorithm to obtain the target planning trajectory of the aircraft.

2. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 1, characterized in that: The expression of the first lift coefficient includes: C L =C L _a+C L _PSJ C L =f(Ma,α,p) Where Ma is the Mach number, α is the angle of attack, p is the jet flow of the active flow actuator, CL_a is a function of Ma and α, C L _PSJ are functions of Ma, α and p, C L represents the lift coefficient; The expression of the first drag coefficient includes: C D =C D _a+C D _PSJ C D =f(Ma,α,p) Where Ma is the Mach number, α is the angle of attack, p is the jet flow rate of the active flow actuator, and C is D _a is a function of Mach number Ma and angle of attack α, C D _PSJ is a function of Mach number Ma, angle of attack α and jet flow rate p, C D represents the drag coefficient; The expression of the first pitching moment coefficient includes: C M =C M _a+C M _PSJ C M =f M (Ma,α,p) Where Ma is the Mach number, α is the angle of attack, p is the jet flow rate of the active flow actuator, and C is M _a is a function of Mach number Ma and angle of attack α, C M _PSJ is a function of Mach number Ma, angle of attack α and jet flow rate p, C M represents the pitching moment coefficient.

3. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 1, characterized in that: The state constraints include control quantity constraints, process constraints, initial constraints and terminal constraints.

4. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 3, characterized in that: The control quantity includes the second-order derivative of the angle of attack, the second-order derivative of the roll angle and the jet flow rate; The expression of the control quantity constraint is: Where Mz represents the pitch moment, Mz = 0.5C M ρV 2 SL, p max They represent the minimum second-order derivative of the roll angle, the maximum second-order derivative of the roll angle and the maximum jet flow rate, respectively. K1 represents the control quantity constraint. f represents the functional expression of the second-order derivative of the angle of attack and the pitching moment. Mz min represents the minimum pitching moment, Mz max Indicates the maximum pitching moment.

5. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 3, characterized in that: The expression of the process constraint is: Among them, k Q is the heat flow rate calculation coefficient, g0 represents the sea level gravity acceleration, q max , n max , D min and T max They are the maximum dynamic pressure, maximum heat flux, maximum overload, minimum drag acceleration, and maximum total jet volume, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H represents the atmospheric density scale, V represents the flight speed of the aircraft, L and D represent the lift acceleration and drag acceleration of the aircraft, respectively, and D min and T max They represent the minimum resistance acceleration and the maximum jet volume respectively, T represents the jet volume, and K2 represents the process constraint.

6. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 3, characterized in that: The expression of the initial constraint is: Among them, represents the initial time t0, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, S represents the initial constraint; The expression of the terminal constraint is: Among them, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, and Φ represents the terminal constraint.

7. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling as claimed in claim 1, characterized in that: The expression of the aircraft trajectory planning model based on the active flow control system is: Wherein, f1 represents the state differential equation, K1 represents the control quantity constraint, K2 represents the process constraint, S represents the initial constraint, Φ represents the terminal constraint, J represents the objective function, P0 represents the optimal control problem, r represents the distance from the center of the earth of the aircraft, V represents the flight speed of the aircraft, θ represents the longitude, φ represents the latitude, γ represents the track angle, ψ represents the heading angle, L and D represent the lift acceleration and drag acceleration of the aircraft respectively, Ω represents the angular velocity of the earth's rotation, σ represents the roll angle, ρ=ρ0exp(-(r-R0) / H) represents the atmospheric density, R0 represents the average radius of the earth, H represents the atmospheric density scale height, m ​​represents the mass of the aircraft, Ω represents the angular velocity of the earth's rotation, and t0 represents the initial time. Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; represents the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, g0 represents the gravitational acceleration at sea level, q max , n max , D min and T max They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum drag acceleration and maximum jet volume, q, and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively, t f Indicates the flight time, D min Indicates the minimum drag acceleration of the aircraft, k Q represents the heat flow rate calculation coefficient, t f Indicates the flight time. Indicates the terminal altitude of the aircraft, is the aircraft terminal velocity, represents the second-order derivative of the angle of attack, represents the second-order derivative of the roll angle, Indicates the maximum value of the second-order inverse of the roll angle, represents the minimum value of the second-order inverse of the roll angle, f represents the functional expression of the second-order derivative of the angle of attack and the pitch moment, p represents the aircraft jet flow rate, T represents the total jet volume, Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, x x Indicates the displacement in the direction of the finger.

8. A high-speed aircraft trajectory planning device based on active flow control multivariable coupling, characterized in that: include: an acquisition module, configured to respectively acquire a first group of correlation coefficients of the aircraft affected by the jet, the first group of correlation coefficients comprising a first lift coefficient expression, a first drag coefficient expression and a first pitch moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control; a model pre-construction module, used for obtaining a second set of correlation coefficients of the aircraft which is not affected by the jet, the second set of correlation coefficients comprising a second lift coefficient expression, a second drag coefficient expression, and a second pitch moment coefficient expression, and replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain a new kinematic equation and a new dynamic equation; A model determination module, used for determining a trajectory planning model of an aircraft based on an active flow control system based on pre-constructed control quantities, constraints and objective functions during the flight of the aircraft, new dynamic equations and new kinematic equations; The trajectory solving module is used to solve the trajectory planning model of the aircraft based on the active flow control system based on the hp adaptive Radau pseudo-spectral algorithm to obtain the target planning trajectory of the aircraft.

9. A computer-readable storage medium, characterized in that: The method comprises instructions, which, when running on a computer, enable the computer to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling as described in any one of claims 1 to 7.

10. An electronic device, characterized in that: The electronic device comprises: at least one processor, memory, and input-output unit; The memory is used to store a computer program, and the processor is used to call the computer program stored in the memory to execute the high-speed aircraft trajectory planning method based on active flow control multivariable coupling according to any one of claims 1 to 7.

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