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

Abstract

The application discloses a high-speed aircraft trajectory planning method and device based on active flow control multivariate coupling, a medium and equipment. The method comprises the following steps: acquiring a first set of correlation coefficients of an aircraft affected by a jet flow, acquiring a second set of correlation coefficients of the aircraft not affected by the jet flow, replacing the second set of correlation coefficients with the first set of correlation coefficients, and obtaining new kinematic equations and new dynamic equations; determining an aircraft trajectory planning model based on an active flow control system based on control variables, constraint conditions and objective functions, the new dynamic equations and the new kinematic equations; and solving the aircraft trajectory planning model based on the active flow control system to obtain a target planning trajectory of the aircraft, which improves the flexibility and efficiency of trajectory planning, enhances the controllability and stability of the aircraft in a complex environment, enables the trajectory planning system to more intelligently respond to various dynamic changes in the flight process, and thus ensures the smooth completion of a flight task.

Description

Technical Field

[0001] The present application relates to the field of aircraft guidance and control technology, 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 applications in aerospace return and long-range rapid strike. Due to their aerodynamic configuration and the harsh flight environment, hypersonic vehicle dynamics models are highly nonlinear, strongly coupled, and exhibit parameter uncertainty. Furthermore, vehicles face complex flight constraints such as dynamic pressure, thermal flow, and overload, leading to a highly complex trajectory planning problem. Therefore, trajectory optimization has long been a key research challenge in aerospace engineering. With the advancement 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 continuous-time optimal control problem based on a performance metric and multiple constraints on state and control variables. Common performance metrics include minimizing fuel consumption, reentry time, total heat load, or maximizing range and velocity. Constraints typically include the equations of motion, necessary safety constraints such as dynamic pressure, heat flow, and overload, and constraints on the terminal target state.

[0004] In existing aircraft trajectory planning methods, the control variables are usually the aircraft's thrust, angle of attack, sideslip angle, and bank angle, and their constraint boundaries are set as fixed parameters; and most of them are 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 this 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 objectives, 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 pitching 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 pitching 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 the target planning trajectory of the aircraft.

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

[0008]

[0009] in, represents the Mach number, represents the angle of attack, Indicates the spray flow rate of the active flow actuator, yes and function, Both 、 and function, C L represents the lift coefficient;

[0010] The expression of the first drag coefficient includes:

[0011]

[0012] Where, represents the Mach number, represents the angle of attack, represents the jet flow rate of the active flow actuator, is the Mach number and angle of attack function, is the Mach number , angle of attack and jet flow function, CD represents the drag coefficient;

[0013] The expression of the first pitching moment coefficient includes:

[0014]

[0015] Where, represents the Mach number, represents the angle of attack, represents the jet flow rate of the active flow actuator, is the Mach number and angle of attack function, is the Mach number , angle of attack and jet flow function, represents the pitching moment coefficient.

[0016] Optionally, the state constraints include control quantity constraints, process constraints, initial constraints and terminal constraints.

[0017] 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:

[0018]

[0019] in, represents the pitching moment, , , , They represent the minimum value of the second-order derivative of the roll angle, the maximum value of the second-order derivative of the roll angle, and the maximum value of the jet flow rate, respectively. represents the control quantity constraint, f The functional expression of the second derivative of the angle of attack and the pitching moment is: Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, K 1 indicates control quantity constraint.

[0020] Optionally, the expression of the process constraint is:

[0021]

[0022] in, is the heat flow rate calculation coefficient, is the acceleration due to gravity at sea level, 、 、 、 and They are maximum dynamic pressure, maximum heat flow rate, maximum overload, minimum resistance acceleration, and maximum jet volume, respectively. represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, Indicates the flight speed of the aircraft. L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, and They represent the minimum resistance acceleration and the maximum jet volume, respectively. T represents the total amount of jet flow, K 2 indicates process constraints.

[0023] Optionally, the initial constraint expression is:

[0024]

[0025] Among them, it means Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, S represents the initial constraint;

[0026] The expression of the terminal constraint is:

[0027]

[0028] in, Indicates the flight time, Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, Represents a terminal constraint.

[0029] Optionally, the expression of the aircraft trajectory planning model based on the active flow control system is:

[0030]

[0031] in, represents the state differential equation, Represents the control quantity constraint, Represents process constraints, represents the initial constraints, Represents terminal constraints, represents the objective function, represents the optimal control problem, Indicates the distance from the center of the earth of the aircraft, Indicates the flight speed of the aircraft. Indicates longitude, Indicates latitude, represents the track angle, represents the heading angle, L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, represents the angular velocity of the Earth's rotation, represents the roll angle, represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, Indicates the mass of the aircraft, represents the angular velocity of the Earth's rotation, Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, is the acceleration due to gravity at sea level, 、 、 、 and They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum resistance acceleration and maximum jet volume, respectively. , and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively. Indicates the flight time, D min Indicates the minimum drag acceleration of the aircraft, represents the heat flow rate calculation coefficient, Indicates the flight time, Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, represents the second-order derivative of the angle of attack, represents the second 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 The functional expression of the second derivative of the angle of attack and the pitching moment is: p represents the aircraft jet flow rate, T represents the total amount of jet flow, Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, x x Indicates the radial displacement.

[0032] 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 obtain 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 pitching moment coefficient expression, wherein the jet influence on the aircraft is generated based on active flow control; a model pre-construction module, used to obtain 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 pitching moment coefficient expression, and replace the second set of correlation coefficients with the first set 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 of the aircraft during flight, 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.

[0033] To achieve the above objectives, the present application also provides a computer-readable storage medium, which includes instructions. When the instructions are run on a computer, the computer executes the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided in the above embodiment.

[0034] 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 and 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.

[0035] 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 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 pitching moment coefficient expression, wherein the jet effect 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 pitching moment coefficient expression, and replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain New kinematic equations and new dynamic equations; based on the pre-built control quantities, constraints and objective functions of the aircraft during flight, the new dynamic equations and the new kinematic equations, the aircraft trajectory planning model based on the active flow control system is determined; 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, 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 flight, thereby ensuring the smooth completion of the flight mission. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flowchart illustrating an embodiment of a high-speed aircraft trajectory planning method based on active flow control multivariable coupling is provided in this application;

[0037] 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;

[0038] FIG3 is a curve showing the lift coefficient changing with the angle of attack and the jet flow rate according to an embodiment of the 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;

[0039] FIG4 is a curve showing the drag 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 FIG4(a) is a curve showing the drag coefficient changing with the angle of attack and the jet flow rate at 1.2 Ma, FIG4(b) is a curve showing the drag coefficient changing with the angle of attack and the jet flow rate at 10 Ma, and FIG4(c) is a curve showing the drag coefficient changing with the angle of attack and the jet flow rate at 15 Ma;

[0040] Fig. 5 is a curve of the pitching moment coefficient changing with the angle of attack according to an embodiment of the trajectory planning method for high-speed aircraft based on active flow control multivariable coupling provided by the present application, wherein Fig. 5(a) is a curve of the pitching moment coefficient changing with the angle of attack and the jet flow rate at 1.2Ma, Fig. 5(b) is a curve of the pitching moment coefficient changing with the angle of attack and the jet flow rate at 10Ma, and Fig. 5(c) is a curve of the pitching moment coefficient changing with the angle of attack and the jet flow rate at 15Ma;

[0041] Figure 6 Fig. 6 is a simulation diagram of the flight height changing with the flight distance according to an embodiment of the trajectory planning method for high-speed aircraft based on active flow control multivariable coupling provided by the present application;

[0042] Figure 7 Fig. 7 is a simulation diagram of the jet flow rate changing with the flight distance according to an embodiment of the trajectory planning method for high-speed aircraft based on active flow control multivariable coupling provided by the present application;

[0043] Figure 8 Fig. 8 is a structure block diagram of the device according to an embodiment of the trajectory planning method for high-speed aircraft based on active flow control multivariable coupling provided by the present application.

[0044] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0045] It should be understood that the specific embodiments described herein merely serve to explain the present application and do not serve to limit the present application.

[0046] In the prior art, there are many methods for the aircraft trajectory planning problem, and the indirect method and the direct method are the most commonly used methods, which are also two basic solving 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 solving. The direct method framework does not need to derive the optimal control equation, and directly uses a nonlinear optimization algorithm to solve the optimal control problem.

[0047] With reference to Figure 1 The trajectory planning method for high-speed aircraft based on active flow control multivariable coupling provided by the first embodiment of the present application can include the following steps.

[0048] S10, a first set of related coefficients of the aircraft affected by the jet flow is obtained respectively, the first set of related coefficients includes a first lift coefficient expression, a first drag coefficient expression and a first pitching moment coefficient expression, wherein the jet flow affecting the aircraft is generated based on active flow control.

[0049] Before step S10, the trajectory planning method for high-speed aircraft based on active flow control multivariable coupling further includes step S00.

[0050] Arrange the flow controller at the head position, such as Figure 2 As shown in Figure 3, the effect of the active flow control system on the lift characteristics of the aircraft is analyzed. The active flow control system can stimulate additional airflow on the aircraft surface, effectively delaying or suppressing airflow separation, thereby changing the lift coefficient. As shown in Figures 3(a)-3(c), Figures 3(a)-3(c) simulate and study the changes of the aircraft's lift coefficient with angle of attack and jet flow at different Mach numbers. Figures 4(a)-4(c) simulate and study the changes of the aircraft's drag coefficient with angle of attack and jet flow at different Mach numbers to analyze the effect of the active flow control system on the aircraft's drag characteristics. The active flow control system can stimulate additional airflow on the aircraft surface, effectively delaying or suppressing airflow separation, and reducing the additional drag caused by separation. The effect of the active flow control system on the aircraft's pitch control torque is analyzed. Active flow control systems can stimulate additional airflow on the surface of an aircraft, changing the point of lift application and, consequently, the pitch control moment. Figures 5(a)-5(c) simulate how the pitch moment coefficient varies with angle of attack and jet flow rate at different Mach numbers. The above analysis demonstrates that active flow control systems can stimulate additional airflow on the surface of an aircraft, changing the point of lift application and, consequently, the pitch control moment. Using a waverider configuration as an example, a flow controller is placed at the head.

[0051] 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.

[0052] 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, so the lift coefficient expression is: It can be:

[0053]

[0054] Where, represents the Mach number, represents the angle of attack, Indicates the spray flow rate of the active flow actuator. is a function of Mach number and angle of attack, yes 、 and function.

[0055] Similarly, the drag coefficient expression is It can be:

[0056]

[0057] in, is also a function of Mach number and angle of attack, Too 、 and function.

[0058] Similarly, the pitching moment coefficient It can be expressed as:

[0059]

[0060] Where, represents the Mach number, represents the angle of attack, Indicates the jet flow rate of the active flow actuator. is the Mach number and angle of attack function, is the Mach number , angle of attack and jet flow function.

[0061] S20. Obtain a second set of correlation coefficients for 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 pitching moment coefficient expression, and replace the second set of correlation coefficients with the first set of correlation coefficients to obtain new kinematic equations and new dynamic equations.

[0062] In an embodiment of the present application, step S20 may include the following execution process:

[0063] First, establish the dynamic equation of the center of mass motion of the aircraft:

[0064]

[0065] Where, represents the angle of attack, represents the roll angle, Indicates thrust, , , L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, represents the Earth's gravitational constant, 、 denote the lift coefficient and the drag coefficient, respectively. represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, represents the aircraft reference area, Indicates the mass of the aircraft, represents the angular velocity of the Earth's rotation.

[0066] Secondly, ignoring the influence of the earth's curvature and wind, according to Newton's kinematic equations, the aircraft motion equation is established in the ballistic coordinate system:

[0067]

[0068] Where, Indicates the distance from the center of the earth of the aircraft, Indicates speed, Indicates longitude, Indicates latitude, represents the track angle, Indicates the heading angle.

[0069] Finally, the first lift coefficient expression, the first drag coefficient expression, and the first pitching moment coefficient expression obtained in step S10 are used to replace the second lift coefficient expression, the second drag coefficient expression, and the second pitching moment coefficient expression in the dynamic equation to obtain new kinematic equations and new dynamic equations.

[0070] S30, determining an aircraft trajectory planning model 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;

[0071] In an embodiment of the present application, step S30 may include the following execution process:

[0072] S301, setting the control quantity, control quantity constraint, initial constraint, terminal constraint, process constraint and objective function during the flight of the aircraft;

[0073] Among them, the traditional aircraft trajectory planning control quantity is the angle of attack and roll angle , after the introduction of active flow control, the control quantity Take the second derivative of the aircraft's angle of attack , the second derivative of the roll angle and aircraft jet flow, . The second derivative of the angle of attack , the second derivative of the roll angle Using jet flow as a control variable allows for more precise control. Using jet flow as a control variable allows for real-time adaptation to airflow changes, maintaining optimal flight performance. This technology has not yet been applied in existing trajectory planning.

[0074] Set the control quantity constraint:

[0075] Under the action of the active flow control system, the second 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 jet flow rate and the second derivative of the roll angle It is also bounded, and the definitions of the above three control constraints are expressed as follows:

[0076]

[0077] in, represents the pitching moment, , , , They are the minimum value of the second derivative of the roll angle, the maximum value of the second derivative of the roll angle and the maximum value of the jet flow rate, respectively.

[0078] Set the initial constraints:

[0079] The initial state of the aircraft is usually known and is recorded as :

[0080]

[0081] Among them, it means Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates the initial latitude; represents the initial track angle; represents the initial heading angle, Indicates the initial quality.

[0082] Set terminal constraints:

[0083] Terminal state constraints :

[0084]

[0085] in, Indicates the flight time, Indicates the terminal altitude of the aircraft, Indicates the terminal velocity of the aircraft.

[0086] Set process constraints:

[0087] In order to ensure the structural safety of the aircraft, trajectory planning generally needs to consider the process constraints of heat flow , dynamic pressure and total overload , during the flight, these three parameters cannot exceed the given maximum value. At the same time, in order to ensure that the glider has sufficient aerodynamic force to achieve trajectory control, the drag acceleration There must be a minimum boundary. Due to the installation of active flow control devices, the maximum amount of jet carried by the aircraft is Nor can it exceed the given maximum value. The definitions of the above five process constraints are as follows:

[0088]

[0089] in, is the heat flow rate calculation coefficient, is the acceleration of gravity at sea level, 、 、 、 and They are maximum dynamic pressure, maximum heat flow rate, maximum overload, minimum resistance acceleration, and maximum total jet volume.

[0090] Set the objective function:

[0091] 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 used as the objective function, where Directional displacement:

[0092]

[0093] S301. Constructing an aircraft trajectory planning model based on flow control

[0094] The trajectory optimization model is described as consisting of the state differential equations , control quantity constraints , process constraints , initial constraints , terminal constraints and the objective function The optimal control problem ;in,

[0095]

[0096] In the formula, represents the state differential equation, Represents the control quantity constraint, Represents process constraints, represents the initial constraints, Represents terminal constraints, represents the objective function, represents the optimal control problem, Indicates the distance from the center of the earth of the aircraft, Indicates the flight speed of the aircraft. Indicates longitude, Indicates latitude, represents the track angle, represents the heading angle, L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, represents the angular velocity of the Earth's rotation, represents the roll angle, represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, Indicates the mass of the aircraft, represents the angular velocity of the Earth's rotation, Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, is the acceleration due to gravity at sea level, 、 、 、 and They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum resistance acceleration and maximum jet volume, respectively. , and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively. Indicates the flight time, D min Indicates the minimum drag acceleration of the aircraft, represents the heat flow rate calculation coefficient, Indicates the flight time, Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, represents the second-order derivative of the angle of attack, represents the second derivative of the roll angle, Indicates the maximum value of the second-order inverse of the roll angle, a second order inverse minimum of a bank angle, f a functional expression of a second order derivative of an angle of attack and a pitch moment, p a jet flow rate of an aircraft, T a total jet flow rate, Mz min a minimum pitch moment, Mz max a maximum pitch moment, x x a pointing displacement.

[0097] S40, solving the aircraft trajectory planning model based on the active flow control system based on the hp-adaptive Radau pseudospectral algorithm to obtain a planned trajectory of the aircraft.

[0098] Specifically, step S40 can include the following execution process:

[0099] S401, initializing a grid interval, letting an iteration number , setting an initial division of the interval and an upper and lower limit of the number of collocation points in the interval ; setting a total number of intervals of the aircraft trajectory as , a current interval as , an initial number of collocation points of each interval as , an error threshold as , and a relative curvature threshold as ;

[0100] S402, discretizing the trajectory planning problem using the Radau pseudospectral method, converting it into an NLP problem for solving, and according to a relative maximum error of the calculated solution ; discretizing the optimal control problem into an NLP problem at the collocation points of each interval and solving it to obtain state variable values and control variable values corresponding to a flight trajectory; calculating a maximum residual error of each interval through the state variable values x and the control variable values ;

[0101] S403, if the of all intervals is less than or , stopping iteration; otherwise, continuing S405;

[0102] According to the size relationship between and , it is judged whether the flight trajectory obtained in step S402 is an optimal trajectory, if the , then the flight trajectory obtained in step S402 is the optimal trajectory, and the optimization is completed. If there are certain intervals , calculate the relative curvature of these intervals , and execute step S405;

[0103] S404, in In the interval, the adaptive strategy is used to update the grid until all grids are updated; judge these intervals and The size relationship of , then use the following formula to redetermine the number of points in the corresponding interval ;

[0104]

[0105] in, For the ceiling function, the positive integer A is an adjustable factor.

[0106] like , then the corresponding interval is divided into subintervals, and set the number of points in each subinterval to ;

[0107]

[0108] Among them, the positive integer B is an adjustable factor.

[0109] The new number and distribution of points in these intervals are obtained, and then step S402 is executed to perform the next iteration.

[0110] S405, Order , go to step S402 for the next iteration.

[0111] S50: Output the path planning result.

[0112] A simulation example is provided below to illustrate this application:

[0113] The results of the simulation of the aircraft's glide trajectory planning with and without the jet are as follows:

[0114] The aircraft has an initial altitude of 70km, an initial velocity of 25Ma, a mass of 900kg, a terminal altitude of 30km, and a terminal minimum velocity of 8Ma. The flight trajectory is planned with the longest range as the planning indicator, with or without a jet. When a jet is present, the maximum jet flow rate is 50g / s, and the maximum jet flow rate is 50kg. The flight altitude and jet flow rate change with the flight distance as shown below: Figure 6 and Figure 7The simulation calculation can obtain that, without the jet flow assistance, the maximum flight distance of the aircraft is 18308km, and after the jet flow is increased by using the active flow control device, the maximum flight distance of the aircraft is increased to 19319km, and it can be seen that the jet flow assistance significantly increases the range of the aircraft, and the specific increase is 1008km.

[0115] Reference Figure 8 On the basis of the above-mentioned embodiment, the application further provides a high-speed aircraft trajectory planning device based on active flow control multivariable coupling. The high-speed aircraft trajectory planning device based on active flow control multivariable coupling 100 comprises an acquisition module 1001, a model pre-construction module, a model determination module 1003 and a trajectory solving module 1004. The acquisition module 1001 is used for respectively acquiring a first set of correlation coefficients of an aircraft affected by jet flow, the first set of correlation coefficients comprising a first lift coefficient expression, a first drag coefficient expression and a first pitching moment coefficient expression, wherein the jet flow affecting the aircraft is generated based on active flow control. The model pre-construction module 1002 is used for acquiring a second set of correlation coefficients of the aircraft not affected by jet flow, the second set of correlation coefficients comprising a second lift coefficient expression, a second drag coefficient expression and a second pitching moment coefficient expression, and the first set of correlation coefficients is used to replace the second set of correlation coefficients to obtain new kinematic equations and new dynamic equations. The model determination module 1003 is used for determining an aircraft trajectory planning model based on an active flow control system based on pre-constructed control variables, constraint conditions and objective functions, the new dynamic equations and the new kinematic equations. The trajectory solving module 1004 is used for solving the aircraft trajectory planning model based on the active flow control system based on an hp self-adaptive Radau pseudospectral algorithm to obtain a target planning trajectory of the aircraft.

[0116] On the basis of the above-mentioned embodiment, the application further provides a computer readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided by any of the above-mentioned embodiments.

[0117] On the basis of the above-mentioned embodiment, the application further provides an electronic device, comprising at least one processor, a memory and an input-output unit. The memory is used for storing a computer program, and the processor is used for calling the computer program stored in the memory to perform the high-speed aircraft trajectory planning method based on active flow control multivariable coupling provided by any of the above-mentioned embodiments.

[0118] The above are only preferred embodiments of the present application and do not 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 including a first lift coefficient expression, a first drag coefficient expression, and a first pitching moment coefficient expression, wherein the jet effect on the aircraft is generated based on active flow control; Obtaining a second set of correlation coefficients for 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 pitching moment coefficient expression, and replacing the second set of correlation coefficients with the first set of correlation coefficients to obtain new kinematic equations and new dynamic equations; Determine an aircraft trajectory planning model based on an active flow control system based on pre-constructed control variables, constraints and objective functions during the flight of the aircraft, the new dynamic equations and the new kinematic equations; The expression of the aircraft trajectory planning model based on the active flow control system is: in, represents the state differential equation, Represents the control quantity constraint, Represents process constraints, represents the initial constraints, Represents terminal constraints, represents the objective function, represents the optimal control problem, Indicates the distance from the center of the earth of the aircraft, Indicates the flight speed of the aircraft. Indicates longitude, Indicates latitude, represents the track angle, represents the heading angle, L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, represents the angular velocity of the Earth's rotation, represents the roll angle, represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, Indicates the mass of the aircraft, represents the angular velocity of the Earth's rotation, Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates the initial latitude; represents the initial track angle; represents the initial heading angle, represents the initial mass, is the acceleration due to gravity at sea level, 、 、 、 and They represent the maximum dynamic pressure, maximum heat flux, maximum overload, minimum resistance acceleration and maximum jet volume, respectively. , and n represent the dynamic pressure, heat flow rate and overload of the aircraft respectively. Indicates the flight time, D min represents the minimum drag acceleration of the aircraft, represents the heat flow rate calculation coefficient, Indicates the flight time, Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, represents the second-order derivative of the angle of attack, represents the second 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 The functional expression of the second derivative of the angle of attack and the pitching moment is: p represents the aircraft jet flow rate, T represents the total amount of jet flow, Mz min represents the minimum pitching moment, Mz max represents the maximum pitching moment, x x Indicates the radial displacement; 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 according to claim 1, characterized in that: The expression of the first lift coefficient includes: in, represents the Mach number, represents the angle of attack, Indicates the spray flow rate of the active flow actuator, yes and function, Both 、 and function, C L represents the lift coefficient; The expression of the first drag coefficient includes: Where, represents the Mach number, represents the angle of attack, represents the jet flow rate of the active flow actuator, is the Mach number and angle of attack function, is the Mach number , angle of attack and jet flow function, CD represents the drag coefficient; The expression of the first pitching moment coefficient includes: Where, represents the Mach number, represents the angle of attack, represents the jet flow rate of the active flow actuator, is the Mach number and angle of attack function, is the Mach number , angle of attack and jet flow function, represents the pitching moment coefficient.

3. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling according to claim 1, characterized in that: 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 according to claim 3, characterized in that: The control variables include 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: in, represents the pitching moment, , , , They represent the minimum value of the second-order derivative of the roll angle, the maximum value of the second-order derivative of the roll angle, and the maximum value of the jet flow rate, respectively. represents the control quantity constraint, f The functional expression of the second derivative of the angle of attack and the pitching moment is: 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 according to claim 3, characterized in that: The expression of the process constraint is: in, is the heat flow rate calculation coefficient, is the acceleration due to gravity at sea level, 、 、 、 and They are maximum dynamic pressure, maximum heat flow rate, maximum overload, minimum resistance acceleration, and maximum jet volume, respectively. represents the atmospheric density, represents the average radius of the Earth, represents the atmospheric density scale height, Indicates the flight speed of the aircraft. L and D They represent the lift acceleration and drag acceleration of the aircraft respectively, and They represent the minimum resistance acceleration and the maximum jet volume, respectively. T represents the total amount of jet flow, Represents a process constraint.

6. The high-speed aircraft trajectory planning method based on active flow control multivariable coupling according to claim 3, characterized in that: The expression of the initial constraint is: Among them, it means Initial time, Indicates the initial altitude of the aircraft; represents the initial velocity; Indicates the initial longitude; Indicates 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: in, Indicates the flight time, Indicates the terminal altitude of the aircraft, represents the terminal velocity of the aircraft, Represents a terminal constraint.

7. A high-speed aircraft trajectory planning device based on active flow control multivariable coupling, applying the high-speed aircraft trajectory planning method based on active flow control multivariable coupling according to any one of claims 1 to 6, characterized in that: include: an acquisition module, configured to respectively acquire a first set of correlation coefficients of an aircraft affected by a jet flow, the first set of correlation coefficients comprising a first lift coefficient expression, a first drag coefficient expression, and a first pitching moment coefficient expression, wherein the jet flow effect on the aircraft is generated based on active flow control; a model pre-construction module, configured to obtain a second set of correlation coefficients for 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 pitching moment coefficient expression, and to replace the second set of correlation coefficients with the first set of correlation coefficients to obtain new kinematic equations and new dynamic equations; a model determination module, configured to determine an aircraft trajectory planning model based on an active flow control system based on pre-constructed control variables, constraints, and objective functions during the flight of the aircraft, the new dynamic equations, and the new kinematic equations; The trajectory solving module is 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.

8. 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 according to any one of claims 1 to 6.

9. 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 6.

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