High-speed aircraft entry phase guidance method and system

Abstract

The invention discloses a guidance method and system for the entry section of a high-speed aircraft, and belongs to the technical field of aircraft navigation guidance and control, and the method comprises the steps: building a standard motion equation of the entry section of the high-speed aircraft under a planet fixed connection coordinate system without considering the rotation motion and flattening of a planet; establishing an error tracking equation of the high-speed aircraft entering section relative to the reference trajectory; and designing a high-speed aircraft trajectory tracking guidance law by using a self-adaptive over-torque sliding mode control method and an error tracking equation of an aircraft entering section relative to the reference trajectory. The method has the advantages of being simple in algorithm and high in robustness and adaptability.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft navigation, guidance and control, and in particular relates to a high-speed aircraft entry-stage guidance method and system. Background Art

[0002] Due to the complexity of the planetary atmosphere, the entry guidance algorithm plays a vital role in precise landing during the atmospheric entry stage of high-speed aircraft. When a high-speed aircraft reenters the atmosphere from outer space, it has extremely high speed and initial kinetic energy. For example, the reentry speed of Earth orbiters and other planetary probes (such as lunar probes) is about the first and second cosmic speeds. This high-speed flight will cause a circle of plasma shielding to form around the aircraft, interrupting the internal and external communications of the aircraft, forming the so-called "black barrier zone". At the same time, the aircraft will be affected by the earth's gravitational field during the reentry process. As the altitude decreases, the potential energy will be converted into work on the surrounding atmosphere, and part of the work will be converted into heat energy, resulting in a high thermal load on the head of the aircraft. The guidance algorithm can generate an optimal landing trajectory based on the initial state of the aircraft and the requirements of the target landing point. In actual flight, the guidance algorithm can track the state of the aircraft in real time to ensure that the aircraft flies along the predetermined trajectory. Appropriate orbit design and guidance laws can reduce the overload and heat load of the aircraft during the reentry process. This helps to protect the structure of the aircraft from damage and ensure that the thermal protection system of the aircraft can work properly. The guidance algorithm can accurately control the speed and attitude of the aircraft to ensure that the aircraft lands at the predetermined landing point. This is especially important for aircraft that require high-precision landing (such as manned spacecraft, space shuttle return capsule, etc.).

[0003] During high-speed flight, the aircraft may be affected by various interference factors (such as atmospheric disturbances, the nonlinear characteristics of the aircraft itself, etc.), which will place higher requirements on the accuracy and stability of the guidance algorithm. In order to meet these challenges, researchers need to continuously improve and optimize the guidance algorithm to improve its adaptability and robustness. When a high-speed aircraft enters the atmospheric stage, the guidance algorithm plays a vital role in precise landing. Through precise trajectory planning and tracking, overload and thermal load control, and control of landing point accuracy, the guidance algorithm can ensure that the aircraft lands safely and accurately at the predetermined location. At the same time, in order to cope with the various challenges that may be encountered during high-speed flight, researchers need to continuously improve and optimize the guidance algorithm.

[0004] In general, there are two main types of entry guidance methods: prediction-correction guidance and reference trajectory tracking guidance. Prediction-correction guidance is not very sensitive to state errors and can control the vehicle to a precise target position, but the requirement for real-time computing power limits its application in engineering practice. Therefore, reference trajectory tracking is the preferred solution for planetary landing missions, but high-speed vehicle models inevitably have state uncertainties and parameter errors. Therefore, it is necessary to design a guidance method with high accuracy and robustness. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a high-speed aircraft entry phase guidance method to achieve continuous control input and eliminate chattering, and has the advantages of simple algorithm, strong robustness and adaptability.

[0006] In order to solve the above technical problems, the present invention is implemented by the following technical solutions: In a first aspect, the present invention provides a high-speed aircraft entry guidance method, comprising: In the planet-fixed coordinate system, the standard equation of motion for the high-speed vehicle's entry phase is established without considering the planet's rotation and flattening. Based on the standard motion equation of the high-speed aircraft entry phase, an error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is established; The trajectory tracking guidance law of the high-speed aircraft is designed by using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft relative to the reference trajectory during entry.

[0007] As a further improvement of the present invention, the standard motion equation of the high-speed aircraft entry phase is as follows:

[0008] in, and are the longitude and latitude of the planet, and They are and The rate of change of is the distance between the center of the planet and the spacecraft, for The rate of change of is the aircraft speed, for The rate of change of is the aircraft flight path angle, for The rate of change of is the heading angle between the projection of the flight speed on the horizontal plane and the east direction of the planet, for The rate of change of is the inclination angle between the lift vector of the aircraft and the longitudinal plane; gravitational acceleration The calculation formula is ,in is the planetary gravitational constant; and It represents the drag acceleration and lift acceleration of an aircraft.

[0009] As a further improvement of the present invention, the and The calculation formula is:

[0010] in, is the aircraft reference area, is the mass of the aircraft, is the atmospheric density, is the lift coefficient, is the drag coefficient, is the lift-to-drag ratio; Atmospheric density It is distributed in an exponential function, and the calculation formula is:

[0011] in, is the planet reference radius, for The atmospheric density at It is the standard height.

[0012] As a further improvement of the present invention, the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is specifically:

[0013] and:

[0014] in, is the reference drag acceleration; is the tracking error of the drag acceleration relative to the reference drag acceleration; is the drag acceleration tracking error First derivative with respect to time; for The rate of change, for The rate of change of represents the uncertainty caused by the lift-to-drag ratio error, where is the additional lift acceleration; and is a nonlinear function, where for The rate of change, is the standard lift acceleration, for The second derivative with respect to time.

[0015] As a further improvement of the present invention, based on the standard motion equation of the high-speed aircraft entry phase, an error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is established, including: The time derivative of the drag acceleration It is expressed as:

[0016] in, for The rate of change of The second derivative of drag acceleration with respect to time for:

[0017] in, represents the guidance law; and is a nonlinear function, specifically:

[0018] make represents the reference resistance acceleration; the resistance acceleration tracking error is defined as , the first-order derivative of the drag acceleration tracking error with respect to time is Based on the standard motion equation of the high-speed aircraft entry phase, considering the uncertainty of the lift-to-drag ratio, the second-order derivative of the drag acceleration tracking error with respect to time is expressed as:

[0019] Then, the dynamic process of tracking resistance acceleration error equation is described as: .

[0020] As a further improvement of the present invention, the sliding mode variable of the adaptive supertorque sliding mode control method is for:

[0021] in, is the tracking error of the drag acceleration relative to the reference drag acceleration, is the drag acceleration tracking error First derivative with respect to time; for Parameters, for Parameters.

[0022] As a further improvement of the present invention, the design of the aircraft trajectory tracking guidance law using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory specifically includes: According to the error tracking equation of the high-speed aircraft entering the reference trajectory, the first-order derivative of the sliding mode variable for:

[0023] in, is a nonlinear function and

[0024] According to the adaptive hypertorsion sliding mode control method, the trajectory tracking guidance law of the aircraft is obtained as follows:

[0025] in, and is the adaptive gain of the guidance law, is the designed guidance law, is a function that varies with time, for The rate of change of Under the guidance law, the sliding mode variable dynamics has the following form: .

[0026] As a further improvement of the present invention, and The method to obtain is:

[0027] in, is the real number that needs to be designed.

[0028] In a second aspect, the present invention provides a high-speed aircraft entry phase guidance system, comprising: The subdivision acquisition module is used to subdivide the total duration of the long-process simulation into multiple simulation calculation time points at equal intervals to obtain a long-process simulation continuous section sequence, and then obtain the grid structure, regulation and operation, and meteorological forecast data; The probability calculation module is used to calculate the instantaneous failure probability and the failure probability due to disasters of the whole network equipment based on the grid structure, control operation and meteorological forecast data, and then build a failure probability model of the whole network equipment; The state determination module is used to calculate the probability power flow distribution of the whole network according to the probability model of the equipment failure of the whole network, and then count the expected over-limit equipment as the probability failure equipment, and determine the operation state of the equipment of the whole network; The section calculation module is used to perform real-time power flow calculation according to the operating status of the equipment in the entire network, and obtain the simulation deduction calculation section at the calculation time point; this cycle is repeated to obtain a long-process simulation deduction continuous section sequence within the simulation period.

[0029] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the high-speed aircraft entry phase guidance method when executing the computer program.

[0030] In a fourth aspect, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the high-speed aircraft entry phase guidance method is implemented.

[0031] In a fifth aspect, the present invention provides a computer program product, wherein the computer program product includes computer instructions, and the computer instructions instruct a computer to execute the high-speed aircraft entry phase guidance method.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects: Compared with other aircraft trajectory tracking guidance laws, the high-speed aircraft entry phase guidance method of the present invention is based on the adaptive hypertorsion sliding mode guidance law, which can achieve high-precision trajectory tracking of the target trajectory in the presence of interference and has a fast algorithm convergence speed; compared with the traditional sliding mode method, the guidance law designed by the present invention can achieve continuous control input and eliminate chattering, and has the advantages of simple algorithm, strong robustness and adaptability.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the specific implementation modes of the present invention, the drawings required for use in the description of the specific implementation modes will be briefly introduced below. Obviously, the drawings described below are some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the embodiments of the present invention or the drawings of related technical solutions in the prior art are introduced below. It should be understood that the drawings introduced below are only for the convenience of clearly describing some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 A flow chart of a high-speed aircraft entry guidance method provided by the present invention; Figure 2 This is a schematic diagram of the force analysis of the high-speed aircraft entry stage; Figure 3 Drag acceleration tracking effect diagram during numerical simulation; Figure 4 Variation curve of drag acceleration tracking error during numerical simulation; Figure 5 This is the distribution diagram of the aircraft parachute opening point position during the numerical simulation process; Figure 6 A high-speed aircraft entry-stage guidance device provided by the present invention; Figure 7 A schematic diagram of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Terminology explanation: High-speed aircraft generally refers to aircraft that can fly faster than the speed of sound (Mach 1, about 1,235 km / h). These aircraft may include but are not limited to: military aircraft, civilian aircraft, missiles, spacecraft, hypersonic aircraft, drones, etc.

[0039] A planet-fixed coordinate system, also called a planet-fixed coordinate system or a planetary coordinate system, is a coordinate system used to describe the position and motion of objects on the surface of a planet or in near-planetary space. This coordinate system is often used in fields such as planetary science, space mission planning, remote sensing, and geographic information systems. The design and implementation of a planet-fixed coordinate system needs to take into account factors such as the rotation, revolution, and gravitational field of the planet to ensure the accuracy and stability of the coordinate system.

[0040] The high-speed vehicle entry phase refers to the process of a vehicle re-entering the Earth's atmosphere from space at high speed. This phase places extremely high demands on the design and materials of the vehicle, as the vehicle will face extreme changes in temperature, pressure and speed when entering the atmosphere.

[0041] The standard equations of motion for high-speed aircraft entry phases usually involve complex aerodynamics and flight mechanics problems. These equations describe the physical laws of the aircraft's motion in the atmosphere, including the balance of forces and torques, conservation of mass and energy, etc.

[0042] like Figure 1 As shown, the first object of the present invention is to provide a high-speed aircraft entry phase guidance method, comprising: S1, in the planet-fixed coordinate system, without considering the planetary rotation and flattening, establish the standard equation of motion for the high-speed aircraft entry phase; S2, establishing an error tracking equation of the high-speed aircraft entry segment relative to a reference trajectory based on the standard motion equation of the high-speed aircraft entry segment; S3, using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory, the aircraft trajectory tracking guidance law is designed.

[0043] The high-speed aircraft entry guidance method provided by the present invention ignores the influence of the planet's rotation and flattening in the planet-fixed coordinate system, which is to simplify the problem and facilitate the establishment of a mathematical model. Based on the above assumptions, a standard motion equation for the high-speed aircraft entry phase is established. This equation describes the motion state of the aircraft in the planet-fixed coordinate system, including position, velocity, acceleration, etc.

[0044] Based on the standard equation of motion, the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is further established. This equation describes the deviation between the actual motion trajectory of the aircraft and the reference trajectory, including position deviation, speed deviation, etc. The aircraft trajectory tracking guidance law is designed by using the adaptive hypertorsion sliding mode control method combined with the error tracking equation. This guidance law can adjust the control instructions of the aircraft in real time according to the actual motion state of the aircraft, so that the aircraft can fly along the reference trajectory.

[0045] Furthermore, by establishing accurate standard motion equations and error tracking equations, and utilizing advanced adaptive hypertorsion sliding mode control methods, the present invention can provide high-precision trajectory tracking guidance. This helps ensure that the aircraft can accurately and stably fly along the reference trajectory, thereby improving the success rate of the flight mission. The adaptive hypertorsion sliding mode control method has strong robustness and can cope with various external interferences and uncertainties. This means that even if complex environmental changes or unknown factors are encountered during actual flight, the present invention can maintain stable guidance performance and ensure the safe flight of the aircraft. The present invention can update the motion state and reference trajectory information of the aircraft in real time, and adjust the guidance instructions in real time based on this information. This helps ensure that the aircraft can respond quickly to external changes during high-speed flight and maintain a stable flight state.

[0046] The present invention is not only applicable to the guidance of the entry phase of a high-speed aircraft, but can also be extended to other flight phases and different types of aircraft, which provides the possibility for its wide application in actual flight missions.

[0047] like Figure 2 As shown, is the ground coordinate system, is the aircraft velocity coordinate system; is the distance between the center of the planet and the spacecraft; and are respectively the lift acceleration and drag acceleration of the aircraft, is the aircraft speed, is the inclination angle between the lift vector of the aircraft and the vertical plane, is the flight path angle, is the projection of the aircraft speed on the horizontal plane and the ground coordinate system The heading angle of the axis.

[0048] As a specific embodiment of the present invention, a high-speed aircraft entry guidance method based on adaptive hypertorsion sliding mode control includes: Step 1: In the planet-fixed coordinate system, without considering the planet's rotation and flattening, establish the standard motion equation of the spacecraft's entry phase, as follows:

[0049] in, and are the longitude and latitude of the planet, and They are and The rate of change of is the distance between the center of the planet and the spacecraft, for The rate of change of is the aircraft speed, for The rate of change of is the aircraft flight path angle, for The rate of change of is the heading angle between the projection of the flight speed on the horizontal plane and the east direction of the planet, for The rate of change of is the inclination angle between the lift vector of the aircraft and the longitudinal plane; gravitational acceleration The calculation formula is ,in is the planetary gravitational constant; and It represents the drag and lift acceleration, which is related to speed, atmospheric density, and aerodynamic coefficient and can be calculated by the following formula:

[0050] in, is the aircraft reference area, is the mass of the aircraft, is the atmospheric density; is the lift coefficient, is the drag coefficient, is the lift-to-drag ratio. Assuming the planet is spherical, the reference radius is , the atmospheric density is distributed as an exponential function, and the expression is:

[0051] in, The reference radius The atmospheric density at It is the standard height.

[0052] Step 2: Establish the error tracking equation of the aircraft entry phase relative to the reference trajectory, as follows: The aircraft determines its trajectory based on the drag acceleration accurately measured by the inertial measurement unit. The time derivative of the drag acceleration is It can be expressed as:

[0053] in, for Rate of change. Second derivative of drag acceleration with respect to time for:

[0054] in, represents the guidance law, and is a nonlinear function, specifically:

[0055] Due to the complexity of the planetary environment, it is difficult to accurately obtain lift, so the lift-to-drag ratio has uncertainty, and the guidance method must be insensitive to changes in the lift-to-drag ratio. Under the uncertainty of the lift-to-drag ratio, the lift acceleration can be expressed as:

[0056] in, is the standard lift acceleration, The additional lift acceleration caused by the uncertainty of lift-to-drag ratio.

[0057] make represents the reference resistance acceleration. The resistance acceleration tracking error is defined as , the time derivative of the drag acceleration tracking error is Considering the uncertainty of lift-to-drag ratio, the second-order derivative of drag acceleration tracking error with respect to time is:

[0058] In summary, the dynamic tracking process of the drag acceleration error can be described as:

[0059] in for The other parameters are as follows:

[0060] represents the uncertainty caused by the lift-to-drag ratio error, which needs to satisfy the assumption that the uncertainty of the aircraft during the entry phase is differentiable and its derivative is bounded.

[0061] Step 3: Using the adaptive hypertorsion sliding mode control method and the error tracking equation of the aircraft entry phase relative to the reference trajectory, design the aircraft trajectory tracking guidance law, specifically: Defining the sliding mode variables in the adaptive hypertorsion sliding mode control method for:

[0062] in, for Parameters, for Parameters.

[0063] According to the error tracking equation of the high-speed aircraft entering the reference trajectory, the first-order derivative of the sliding mode variable for:

[0064] in, is a nonlinear function, and its specific expression is

[0065] According to the basic principle of adaptive hypertorsion sliding mode control, the trajectory tracking guidance law of the aircraft is designed as follows:

[0066] in, and is the adaptive gain in the guidance law, is the designed guidance law, is a function that varies with time, for Under the guidance law, the sliding mode variable dynamic formula has the following form:

[0067] in, and The method to obtain is:

[0068] in, is the real number that needs to be designed.

[0069] In view of the uncertainty and parameter error problems in the prior art, the present invention designs a robust adaptive super-torsion sliding mode guidance law based on the standard motion model of the high-speed aircraft entry phase and taking into account the interference caused by the unknown lift-to-drag ratio. The law can achieve high-precision trajectory tracking of the target trajectory and has a fast algorithm convergence speed. The law has the advantages of simple algorithm, strong robustness and adaptability.

[0070] When the high-speed aircraft entry guidance method provided by the embodiment of the present invention is applied, the state information of the initial and final moments of the aircraft entry during the numerical simulation is shown in Table 1. The parameters of the adaptive super-torsion sliding mode guidance method are shown in Table 2.

[0071] Table 1 The status at the initial and final time of entering the segment

[0072] Table 2 Parameters of adaptive hypertorsion sliding mode guidance method

[0073] Figure 3 and Figure 4 They respectively represent the drag acceleration tracking effect diagram and the drag acceleration tracking error variation curve under the entry stage guidance method designed by the present invention, Figure 3 It can be seen that the reference resistance acceleration curve basically coincides with the real resistance acceleration curve; Figure 4 The drag acceleration tracking error curve shows that it decreases rapidly at first and then remains basically level. The results show that the drag acceleration can accurately track the reference drag acceleration, and the tracking error is the largest at the initial moment, then decreases rapidly, and finally approaches 0.

[0074] The accuracy and robustness of the planetary entry guidance method are evaluated by the distribution of parachute deployment points. Figure 5The results of 50 Monte Carlo simulations of the parachute opening point of the aircraft when using the method provided by the present invention are given. The small circle and the large circle represent the area 5km and 10km away from the target point respectively. The results show that when using the guidance method provided by the present invention, about 85.8% of the landing points of the aircraft in the entry phase are within 5km and 99.8% are within 10km away from the target point.

[0075] In summary, the high-speed aircraft entry phase guidance method designed by the present invention has the advantages of high precision, strong robustness, real-time and wide applicability, and can provide a strong guarantee for the stable flight of the high-speed aircraft.

[0076] like Figure 6 As shown, the third object of the present invention is to provide a high-speed aircraft entry phase guidance system, comprising: The motion equation establishment module 100 is used to establish the standard motion equation of the high-speed aircraft entry phase in the planet-fixed coordinate system without considering the planet's rotation and flattening; The error tracking equation establishing module 200 is used to establish the error tracking equation of the high-speed aircraft entry segment relative to the reference trajectory based on the standard motion equation of the high-speed aircraft entry segment; The tracking guidance law design module 300 is used to design the aircraft trajectory tracking guidance law by using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory.

[0077] The high-speed aircraft entry-stage guidance system of the present invention is based on the high-speed aircraft entry-stage guidance method.

[0078] like Figure 7 As shown, the third object of the embodiment of the present invention is to provide an electronic device, including a memory 401, a processor 402, and a computer program stored in the memory 401 and executable on the processor, wherein the processor implements the above-mentioned high-speed aircraft entry guidance method when executing the computer program. It also includes a communication interface 403 and a bus 404.

[0079] A fourth objective of an embodiment of the present invention is to provide a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the high-speed aircraft entry phase guidance method described above is implemented.

[0080] A fifth objective of an embodiment of the present invention is to provide a computer program product, wherein the computer program product includes computer instructions, and the computer instructions instruct a computer to execute the above-mentioned high-speed aircraft entry phase guidance method.

[0081] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0082] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0083] The present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) containing computer-usable program codes.

[0084] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0085] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0086] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the aforementioned embodiments, those of ordinary skill in the art should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the aforementioned embodiments within the technical scope disclosed by the present invention, or can easily conceive of changes, or make equivalent replacements for some of the technical features therein. Such modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention.

Claims

1. A high-speed aircraft entry guidance method, characterized in that: include: In the planet-fixed coordinate system, the standard equation of motion for the high-speed vehicle's entry phase is established without considering the planet's rotation and flattening. Based on the standard motion equation of the high-speed aircraft entry phase, an error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is established; The trajectory tracking guidance law of the high-speed aircraft is designed by using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft relative to the reference trajectory during entry.

2. A high-speed aircraft entry guidance method according to claim 1, characterized in that: The standard motion equation of the high-speed aircraft entry phase is as follows: in, and are the longitude and latitude of the planet, and They are and The rate of change of is the distance between the center of the planet and the spacecraft, for The rate of change of is the aircraft speed, for The rate of change of is the aircraft flight path angle, for The rate of change of is the heading angle between the projection of the flight speed on the horizontal plane and the east direction of the planet, for The rate of change of is the inclination angle between the lift vector of the aircraft and the longitudinal plane; gravitational acceleration The calculation formula is ,in is the planetary gravitational constant; and It represents the drag acceleration and lift acceleration of an aircraft.

3. A high-speed aircraft entry guidance method according to claim 2, characterized in that: Said and The calculation formula is: in, is the aircraft reference area, is the mass of the aircraft, is the atmospheric density, is the lift coefficient, is the drag coefficient, is the lift-to-drag ratio; Atmospheric density It is distributed in an exponential function, and the calculation formula is: in, is the planet reference radius, for The atmospheric density at It is the standard height.

4. A high-speed aircraft entry guidance method according to claim 3, characterized in that: The error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is specifically: and: in, is the reference drag acceleration; is the tracking error of the drag acceleration relative to the reference drag acceleration; is the drag acceleration tracking error First derivative with respect to time; for The rate of change, for The rate of change of represents the uncertainty caused by the lift-to-drag ratio error, where is the additional lift acceleration; and is a nonlinear function, where for The rate of change, is the standard lift acceleration, for The second derivative with respect to time.

5. A high-speed aircraft entry guidance method according to claim 4, characterized in that: Based on the standard motion equation of the high-speed aircraft entry phase, an error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory is established, including: The time derivative of drag acceleration It is expressed as: in, for The rate of change of The second derivative of drag acceleration with respect to time for: in, represents the guidance law; and is a nonlinear function, specifically: make represents the reference resistance acceleration; the resistance acceleration tracking error is defined as , the first-order derivative of the drag acceleration tracking error with respect to time is Based on the standard motion equation of the high-speed aircraft entry phase, considering the uncertainty of the lift-to-drag ratio, the second-order derivative of the drag acceleration tracking error with respect to time is expressed as: Then, the dynamic process of tracking resistance acceleration error equation is described as: 。 6. A high-speed aircraft entry guidance method according to claim 1, characterized in that: The sliding mode variable of the adaptive supertorsion sliding mode control method for: in, is the tracking error of the drag acceleration relative to the reference drag acceleration, is the drag acceleration tracking error First derivative with respect to time; for Parameters, for Parameters.

7. A high-speed aircraft entry guidance method according to claim 6, characterized in that: The method of designing the aircraft trajectory tracking guidance law by using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory specifically includes: According to the error tracking equation of the high-speed aircraft entering the reference trajectory, the first-order derivative of the sliding mode variable for: in, is a nonlinear function and According to the adaptive hypertorsion sliding mode control method, the trajectory tracking guidance law of the aircraft is obtained as follows: in, and is the adaptive gain of the guidance law, is the designed guidance law, is a function that varies with time, for The rate of change of Under the guidance law, the sliding mode variable dynamics has the following form: 。 8. A high-speed aircraft entry guidance method according to claim 7, characterized in that: and The method to obtain is: in, is the real number that needs to be designed.

9. A high-speed aircraft entry guidance system, characterized in that: include: The motion equation establishment module is used to establish the standard motion equation of the high-speed aircraft entry phase in the planet-fixed coordinate system without considering the planet's rotation and flattening; An error tracking equation establishment module is used to establish an error tracking equation of the high-speed aircraft entry segment relative to the reference trajectory based on the standard motion equation of the high-speed aircraft entry segment; The tracking guidance law design module is used to design the aircraft trajectory tracking guidance law by using the adaptive hypertorsion sliding mode control method and the error tracking equation of the high-speed aircraft entry phase relative to the reference trajectory.

10. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the high-speed aircraft entry phase guidance method as claimed in any one of claims 1 to 8 when executing the computer program.

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