Self-adaptive gravity compensation trajectory correction method based on preposed angle

Abstract

The invention discloses a self-adaptive gravity compensation trajectory correction method based on a preposed angle, and belongs to the technical field of aircraft guidance control, the dynamic mapping relation between trajectory deviation and gravity compensation amount is constructed through preposed angle information measured by an aircraft in real time, a gravity compensation coefficient is adjusted in a self-adaptive mode to correct a trajectory, and the trajectory deviation is corrected. The compensation amount is reduced to suppress ballistic lifting when a close-distance target is attacked, the compensation is enhanced to offset the falling effect when a long-distance target is attacked, the problem that the guidance effect is affected due to the fact that gravity compensation is fixed when targets of different distances are attacked in a traditional method is solved, and dependence on remaining time and other parameters difficult to measure in other methods is reduced. And the striking precision and the firing range of the aircraft to different targets are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft guidance and control, and particularly relates to an adaptive gravity compensation trajectory correction method based on the lead angle. Background Art

[0002] In the guidance and control of aircraft, gravity compensation is the core means to suppress the ballistic droop and improve the hitting accuracy. Traditional gravity compensation methods usually based on fixed proportional coefficients statically correct the ballistic trajectory by presetting the gravity acceleration components. For example, the classical gravity compensation proportional guidance law corrects the ballistic trajectory by canceling the gravity components. However, such methods have significant limitations in practical applications: when there is a large deviation between the attack distance and the preset ballistic trajectory, the fixed compensation coefficient is difficult to adapt to the dynamic changes of the relative motion state between the missile and the target. For example, in the close-range attack scenario, the fixed compensation causes the ballistic trajectory to rise and miss the target due to excessive cancellation of the gravity components; while in the long-range attack, insufficient compensation exacerbates the ballistic droop, ultimately leading to an increase in the miss distance. This fixed compensation strategy severely limits the strike effectiveness of the aircraft.

[0003] Existing improvement schemes attempt to improve the adaptability by dynamically adjusting the gravity compensation coefficient. For example, adopting a phased coefficient switching strategy or adjusting the compensation amount based on the ballistic height threshold. However, such methods have problems such as relying on parameters that are difficult to accurately obtain in real time, such as the remaining time, resulting in complex engineering implementation; the feedback information is single, only adjusting the compensation amount based on the line-of-sight angular velocity between the missile and the target or the ballistic height information, without fully utilizing the multi-dimensional information measured by the on-board sensors in real time, resulting in lag in correction; the adaptive ability is limited, and existing compensation strategies mostly rely on preset conditions or theoretical ballistic prediction, and cannot generate the compensation amount in real time according to the actual ballistic deviation. Some methods compensate by correcting the theoretical ballistic trajectory in advance, but they rely on an off-line calculation model and are difficult to cope with real-time dynamic errors.

[0004] Therefore, there is an urgent need for a method that can autonomously adjust the gravity compensation amount based on the real-time state of the aircraft, so as to break through the limitation of the attack range of traditional methods and achieve the flexible correction effect of "correcting more for near-range attacks and less for far-range attacks". Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an adaptive gravity compensation trajectory correction method based on the lead angle, which constructs an adjustment strategy for the gravity compensation amount through the lead angle information, adjusts the gravity compensation amount in real time and adaptively, realizes the trajectory correction effect of "correcting more for near-range attacks and less for far-range attacks" of the aircraft, and significantly improves the strike range and accuracy of the aircraft against the target.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] An adaptive gravity compensation trajectory correction method based on the lead angle, comprising the following steps:

[0008] S1. Use the integrated navigation system of the aircraft to measure the speed V of the aircraft in the northeast sky coordinate system in real time. e ,V n ,V s and position x n ,y n ,z n , and the missile-target sight angle q is obtained by measuring and filtering the seeker g and the missile-target line-of-sight angular velocity

[0009] S2, according to the position x n ,y n ,z n The latitude φ and height h information in the real-time calculation of gravity acceleration g; then according to x n and n Calculate the transformation matrix L from the navigation coordinate system to the ground coordinate system, and then use the speed V e ,V n ,V s The velocity V of the aircraft in the ground coordinate system is calculated by the transformation matrix L x ,V y ,V z and the relative velocity V xr ,V yr ,V zr , and according to V x ,V y The trajectory inclination angle θ is calculated, and the sight angle q g The leading angle η of the aircraft velocity vector is calculated based on the relative velocity V of the projectile and the target. xr ,V yr ,V zr Calculate the relative speed V between the aircraft and the target m ;

[0010] S3, according to the current relative speed V between the aircraft and the target m and the missile-target line-of-sight angular velocity Calculate the proportional guidance command a in the guidance command yc ;

[0011] S4. Calculate the adaptive gravity compensation instruction a according to the real-time changes of the trajectory inclination angle θ and the lead angle η g , and through the adaptive gravity compensation instruction a g and proportional guidance command a yc Computational Synthesis Instruction A y , in order to achieve the purpose of trajectory correction.

[0012] As a further preferred embodiment of the present invention, S2 specifically includes:

[0013] According to the latitude φ and altitude h information at position x n , y n , z n , calculate the gravitational acceleration g in real time. The formula is as follows:

[0014]

[0015] where R = 6378137;

[0016] Calculate the transformation matrix L from the navigation coordinate system to the ground coordinate system. The formula is as follows:

[0017]

[0018] where ψ is the yaw rotation angle between the northeast - up coordinate system and the ground coordinate system,

[0019] Then, using the velocity V e , V n , V s and the transformation matrix L, calculate the velocity V x , V y , V z of the aircraft in the ground coordinate system and the relative velocity V xr , V yr , V zr between the missile and the target. The formula is as follows:

[0020] [V x V y V z T = L[V e V n V s T

[0021] [V xr V yr V zr T = L[V e - V et V n - V nt V s - V st T

[0022] where V e , V n , V s are the east - ward velocity, north - ward velocity, and up - ward velocity of the aircraft in the northeast - up coordinate system respectively, and V x , V y , V​​​​z are the x-direction, y-direction, and z-direction velocities of the aircraft in the ground coordinate system, respectively, V xr , V yr , V zr are the relative velocities of the aircraft with respect to the target in the x-direction, y-direction, and z-direction, respectively, V et , V nt , V st are the northward velocity, eastward velocity, and upward velocity of the target in the northeast-up coordinate system;

[0023] And based on V x , V y the ballistic inclination angle θ is calculated, and the formula is as follows:

[0024]

[0025] After the aircraft enters the terminal guidance stage, the aircraft velocity vector lead angle η is calculated once every m frames of measured data. The formula for the aircraft velocity vector lead angle η is as follows:

[0026] η = q g - θ

[0027] where q g is the line-of-sight angle between the missile and the target;

[0028] Based on the relative velocity V between the missile and the target xr , V yr , V zr the relative velocity V between the aircraft and the target is calculated m , and the formula is as follows:

[0029]

[0030] As a further preference of the present invention, the calculation formula for S3 is:

[0031]

[0032] where N represents a proportionality coefficient, and 2 < N < 6, a yc is the proportional navigation command, V m is the relative velocity between the current aircraft and the target, is the line-of-sight angular velocity between the missile and the target.

[0033] As a further preference of the present invention, the formula for calculating the adaptive gravity compensation command a g in S4 is as follows:

[0034]

[0035] where k gθ is the gravity compensation coefficient related to the ballistic inclination angle of the aircraft, k is the gravity compensation coefficient related to the attack angle when the seeker captures the target gη k is the gravity compensation coefficient related to the lead angle of the aircraft;

[0036] Calculate the gravity compensation coefficient k according to the ballistic inclination angle θ gθ , the formula is as follows:

[0037] k gθ = cosθ

[0038] Judge the threshold interval where the ballistic inclination angle θ0 is located when the aircraft enters the terminal guidance stage, and then determine the gravity compensation coefficient related to the attack angle when the seeker captures the target The formula is as follows:

[0039]

[0040] Among them, k g1 , k g2 and k g3 are the gravity compensation coefficients in different intervals, and θ1 and θ2 are the ballistic inclination angle thresholds;

[0041] Judge the threshold interval and positive and negative of the amplitude of the lead angle η of the aircraft, and then adaptively adjust the gravity compensation coefficient k related to the lead angle of the aircraft gη ,

[0042] The formula is as follows:

[0043]

[0044] Among them, k gη11 , k gη12 , k gη21 , k gη22 , k gη31 , k gη32 and k gη4 are the gravity compensation coefficients in different intervals respectively, and η1, η2 and η3 are the lead angle thresholds.

[0045] As a further preference of the present invention, in S4, the comprehensive guidance command a g is calculated through the adaptive gravity compensation command a yc and the proportional guidance command a y , the formula is as follows:

[0046]

[0047] As a further preference of the present invention, the proportional coefficient N in S3 is 4.

[0048] As a further preference of the present invention, in S2, the lead angle η of the aircraft velocity vector is calculated every m frames of data measured, where m is 20.

[0049] As a further preference of the present invention, in S4, k g1 = 1.3, k g2 = 1, k g3 = 0.7, θ1 = -20, θ2 = -35.

[0050] As a further preference of the present invention, in S4, k gη11 = 0.7, k gη12 = -0.5, k gη21 = 0.4, k gη22 = -0.3, k gη31 = 0.3, k gη32 = -0.2, k gη4 = 0, η1 = 10, η2 = 5, η3 = 3.

[0051] The beneficial effects of the present invention are as follows:

[0052] The present invention dynamically and adaptively adjusts the gravity compensation amount through the pre-angle information measured in real time, effectively solving the problems of "under-correction for long-distance targets and over-correction for short-distance targets" existing in traditional fixed gravity compensation methods. Based on the strong correlation between the pre-angle and the ballistic deviation, an adaptive correction relationship is constructed. When attacking short-distance targets, the gravity compensation coefficient is reduced through the pre-angle information to avoid excessive ballistic elevation, and when attacking long-distance targets, the compensation amount is adaptively enhanced to suppress ballistic droop, significantly improving the strike accuracy and range for targets with different ranges.

[0053] Compared with traditional compensation strategies that rely on indirect parameters such as remaining time, the present invention directly uses the pre-angle to map the real-time ballistic deviation, reduces parameter dependence and simplifies the calculation process, combines with the proportional navigation law to achieve the flexible control effect of "correcting for long-distance targets when attacking short-distance targets and correcting for short-distance targets when attacking long-distance targets", expands the strike ability of the aircraft in different scenarios, optimizes the calculation efficiency at the same time, avoids the calculation burden brought by multi-dimensional parameter solution, meets the strict real-time requirements of ballistic correction, and improves the multi-task adaptability of the aircraft.

[0054] Other advantages, objectives and features of the present invention will be described in the subsequent specification, and to some extent, they are obvious to those skilled in the art, or those skilled in the art can obtain teachings from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to make the objectives, technical solutions and beneficial effects of the present invention clearer, the present invention provides the following drawings for description:

[0056] Figure 1 It is a geometric schematic diagram of the intersection of the aircraft and the target in the longitudinal plane;

[0057] Figure 2 is the lead angle change curve for different target distance deviations;

[0058] Figure 3 is the comparison of the full - length longitudinal trajectory and its partial enlarged view under a certain release condition;

[0059] Figure 4 is the lead angle comparison curve in the terminal guidance stage under a certain release condition;

[0060] Figure 5 is the gravity compensation command comparison curve in the terminal guidance stage under a certain release condition;

[0061] Figure 6 is the overload command comparison curve in the terminal guidance stage under a certain release condition;

[0062] Figure 7 is the overall flow schematic diagram of an adaptive gravity - compensation trajectory correction method based on the lead angle of the present invention. Specific Embodiment

[0063] As Figures 1 to 7 shown, the present invention discloses an adaptive gravity - compensation trajectory correction method based on the lead angle, and the specific implementation steps are as follows:

[0064] Taking a certain type of axisymmetric aircraft as an example, the rendezvous relationship between the aircraft and the target in the longitudinal plane is as Figure 1 shown, where n m is the normal overload of the aircraft, and y m is the longitudinal height of the aircraft, and the implementation process of the present invention is introduced:

[0065] S1. Use the integrated navigation system of the axisymmetric aircraft to measure the velocity V e , V n , V s of the aircraft in the northeast - celestial coordinate system in real - time and the position x n , y n , z n . The seeker of the aircraft measures and filters to obtain the line - of - sight angle q g between the missile and the target and the line - of - sight angular velocity

[0066] where V e , V n , V s are the east - ward velocity, north - ward velocity, and celestial - ward velocity of the aircraft in the northeast - celestial coordinate system respectively, and x n , y n , z n are the east - ward position, north - ward position, and celestial - ward position of the aircraft in the northeast - celestial coordinate system respectively.

[0067] S2. Use the position and velocity information of the aircraft obtained by real-time measurement to calculate information such as gravitational acceleration, velocity, and ballistic inclination angle. Specifically:

[0068] S21. According to the latitude φ and altitude h information of the aircraft, calculate the accurate gravitational acceleration g in real time.

[0069]

[0070] where R = 6378137;

[0071] S22. Calculate the transformation matrix L from the navigation coordinate system to the ground coordinate system.

[0072]

[0073] where ψ is the yaw rotation angle between the northeast-up coordinate system and the ground coordinate system

[0074] S23. Use the information obtained by real-time measurement of the integrated navigation system and the transformation relationship between the northeast-up coordinate system and the ground coordinate system to calculate the velocity V of the aircraft in the ground coordinate system x , V y , V z and the relative velocity V between the missile and the target xr , V yr , V zr .

[0075] [V x V y V z T = L[V e V n V s T

[0076] [V xr V yr V zr T = L[V e - V et V n - V nt V s - V st T

[0077] where V x , V y , V z are the x-direction, y-direction, and z-direction velocities of the aircraft in the ground coordinate system respectively, and V xr , V yr , V​​​​zr are the relative velocities of the aircraft with respect to the target in the x, y, and z directions, respectively, and V et , V nt , V st are the northward velocity, eastward velocity, and upward velocity of the target in the northeast-up coordinate system.

[0078] Furthermore, using the information obtained in the above steps, the ballistic inclination angle θ and the relative velocity V between the current aircraft and the target are calculated m .

[0079]

[0080] After the axisymmetric aircraft enters the terminal guidance stage, the velocity vector lead angle η of the aircraft is calculated once every 20 frames of data measurement.

[0081] η = q g - θ

[0082] In the case of different target distances, the amplitude and sign of the lead angle η are different. As Figure 2 shown, the dotted line represents the case of hitting near and repairing far, and the solid line represents the case of hitting far and repairing near.

[0083] S3. According to the relative velocity V between the current aircraft and the target obtained m and the line-of-sight angular velocity calculate the proportional navigation term a in the guidance command yc , usually 2 < N < 6.

[0084]

[0085] N represents the proportionality coefficient, and the proportionality coefficient N is selected as 4.

[0086] S4. According to the real-time changes of the ballistic inclination angle θ and the lead angle η obtained in the above steps, perform adaptive gravity compensation on the guidance command. The gravity compensation coefficients mainly include:

[0087] the gravity compensation coefficient k related to the ballistic inclination angle of the aircraft gθ , the gravity compensation coefficient related to the attack angle when the seeker captures the target, and the gravity compensation coefficient k related to the lead angle of the aircraft gη .

[0088] According to the ballistic inclination angle θ, calculate the gravity compensation coefficient k gθ .

[0089] k gθ = cosθ

[0090] Judge the threshold interval where the ballistic inclination angle θ0 of the aircraft is located when it enters the terminal guidance stage, and then determine the gravity compensation coefficient related to the attack angle when the seeker captures the target

[0091]

[0092] Judge the threshold interval and positive / negative of the amplitude of the lead angle η of the aircraft, and then adaptively adjust the gravity compensation coefficient k related to the lead angle of the aircraft gη 。

[0093]

[0094] The gravity compensation term a in the guidance command g is:

[0095]

[0096] The integrated guidance command consists of a proportional navigation command and an adaptive gravity compensation command

[0097]

[0098] The adaptive guidance command calculated through the above steps can adjust the gravity compensation term according to the change of the lead angle of the aircraft, make full use of the gravity factor for ballistic correction, improve the ability of the guidance control loop to resist uncertain factors, is easy to be implemented in engineering, and significantly expands the combat effectiveness and applicability of the aircraft

[0099] For the scenario where the horizontal distance between the target and the aircraft launch point is 18 km, two aircraft of the same model are launched for simulation. Their launch speed is 600 m / s, the launch angle is 45°, there is no off-axis angle, and the aerodynamic pull deviation is 1.1. When the target is captured, the horizontal distance increases by 800 m compared with the binding moment, which belongs to the situation of "hitting near and correcting far". The following two ballistic curves are obtained respectively Figure 3 as shown in

[0100] The first aircraft is guided by the proportional navigation guidance law in the mid-course guidance stage and by the adaptive gravity compensation ballistic correction guidance law in the terminal guidance stage. Ensure that the seeker captures the target and the ballistic is smoothly connected in the mid-course and terminal handover section. Its ballistic curve is as shown in Figure 3 "Adaptive gravity compensation" in

[0101] The second aircraft is guided by the proportional navigation guidance law in the mid-course guidance stage and by the traditional fixed over-gravity compensation guidance law in the terminal guidance stage. Ensure that the seeker captures the target and the ballistic is smoothly connected in the mid-course and terminal handover section. Its ballistic curve is as shown in Figure 3 "Fixed over-gravity compensation" in

[0102] The traditional fixed overweight compensation guidance law adopted is as follows:

[0103]

[0104] From Figure 3 It can be seen from the two flight trajectories in that the miss distance of the aircraft adopting the adaptive gravity compensation guidance law in the present invention is 0.26 m, which is better than 4.2 m of the traditional overweight compensation guidance law, indicating that the guidance accuracy can be improved and the attack range can be expanded through the adaptive adjustment of the gravity compensation term.

[0105] From Figure 4 It can be seen from the two lead angle change curves in that the lead angle of the aircraft adopting the adaptive gravity compensation guidance law in the present invention converges to 0 faster, while the traditional overweight compensation guidance law converges slowly and does not converge to 0 finally.

[0106] From Figure 5 and Figure 6 By comparing the gravity compensation command curve and the overload command curve in, it can be seen that the gravity compensation command and the overload command of the aircraft adopting the adaptive gravity compensation guidance law in the present invention are adaptively adjusted according to the change of the lead angle.

[0107] The present invention dynamically and adaptively adjusts the gravity compensation amount through the lead angle information measured in real time, effectively solving the problems of "under-correction for long-range hitting and over-correction for short-range hitting" existing in the traditional fixed gravity compensation method when attacking targets at different distances. Based on the strong correlation between the lead angle and the ballistic deviation, an adaptive correction relationship is constructed. When attacking a short-range target, the gravity compensation coefficient is reduced through the lead angle information to avoid excessive ballistic lift. When attacking a long-range target, the compensation amount is adaptively increased to suppress the ballistic drop, significantly improving the hitting accuracy and range for targets with different ranges.

[0108] Compared with the traditional compensation strategy that relies on indirect parameters such as the remaining time, the present invention directly uses the lead angle to map the real-time ballistic deviation, reduces the parameter dependence and simplifies the calculation process, combines the proportional navigation law to achieve the flexible control effect of "correcting for long-range hitting when hitting near and correcting for short-range hitting when hitting far", expands the hitting ability of the aircraft in different scenarios, optimizes the calculation efficiency at the same time, avoids the calculation burden brought by multi-dimensional parameter solution, meets the strict requirements of real-time for ballistic correction, and improves the multi-task adaptability of the aircraft.

[0109] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. An adaptive gravity compensation trajectory correction method based on the lead angle, characterized in that: It includes the following steps: S1. Measure the velocity V of the aircraft in the northeast celestial coordinate system in real time through the integrated navigation system of the aircraft e , V n , V s and the position x n , y n , z n , and measure and filter the line-of-sight angle q between the missile and the target through the seeker g and the line-of-sight angular velocity between the missile and the target S2. Calculate the gravitational acceleration g in real time according to the latitude φ and altitude h information at position x n , y n , z n . Then calculate the transformation matrix L from the navigation coordinate system to the ground coordinate system according to x n and y n . Then use the velocity V e , V n , V s and the transformation matrix L to calculate the velocity V x , V y , V z of the aircraft in the ground coordinate system and the relative velocity V xr , V yr , V zr between the projectile and the target. And calculate the ballistic inclination angle θ according to V x , V y . Then calculate the lead angle η of the aircraft velocity vector according to the line-of-sight angle q g between the projectile and the target and the ballistic inclination angle θ. And calculate the relative velocity V xr , V yr , V zr between the aircraft and the target m . S3. Calculate the proportional navigation command a in the guidance command based on the relative velocity V between the current aircraft and the target m and the angular velocity of the line of sight between the missile and the target ; yc ; S4. Calculate the adaptive gravity compensation command a according to the real-time changes of the ballistic inclination angle θ and the lead angle η g , and through the adaptive gravity compensation command a g and the proportional navigation command a yc calculate the comprehensive guidance command a y to achieve the purpose of ballistic correction.

2. The adaptive gravity compensation trajectory correction method based on the lead angle according to claim 1, wherein: Specifically, S2 includes: According to the position x n , y n , z n , the latitude φ and altitude h information, calculate the gravitational acceleration g in real time, and the formula is as follows: Wherein, R = 6378137; Calculate the conversion matrix L from the navigation coordinate system to the ground coordinate system, and the formula is as follows: where ψ is the yaw rotation angle between the northeast celestial coordinate system and the ground coordinate system. Reuse speed V e ,V n ,V s and the transformation matrix L to calculate the speed V of the aircraft in the ground coordinate system x ,V y ,V z and the relative speed V between the projectile and the target xr ,V yr ,V zr , the formula is as follows: [V x V y V z T =L[V e V n V s T ​​ [V xr V yr V zr T = L[V e -V et V n -V nt V s -V st T ​​ Among them, V e , V n , V s are respectively the eastward velocity, northward velocity, and upward velocity of the aircraft in the northeast-up coordinate system. V x , V y , V z are respectively the x-direction, y-direction, and z-direction velocities of the aircraft in the ground coordinate system. V xr , V yr , V zr are respectively the relative velocities of the aircraft with respect to the target in the x-direction, y-direction, and z-direction. V et , V nt , V st are the northward velocity, eastward velocity, and upward velocity of the target in the northeast-up coordinate system; and according to V x , V y calculate the ballistic inclination angle θ, and the formula is as follows: After the aircraft enters the terminal guidance stage, the flight vehicle velocity vector lead angle η is calculated once every m frames of data are measured. The formula for the flight vehicle velocity vector lead angle η is as follows: η = q g -θ where q g is the line-of-sight angle between the projectile and the target; According to the relative velocity V between the projectile and the target xr , V yr , V zr the relative velocity V between the aircraft and the target is calculated m , and the formula is as follows:

3. An adaptive gravity compensation trajectory correction method based on the lead angle according to claim 1, characterized in that: The calculation formula of S3 is: Among them, N represents a proportionality coefficient, and 2 < N < 6, a yc is a proportional navigation command, V m is the relative velocity between the current aircraft and the target, is the line-of-sight angular velocity between the missile and the target.

4. An adaptive gravity compensation trajectory correction method based on the lead angle according to claim 3, characterized in that: Calculate the adaptive gravity compensation command a in S4 g The formula is as follows: where k gθ is the gravity compensation coefficient related to the ballistic inclination angle of the aircraft, is the gravity compensation coefficient related to the attack angle when the seeker captures the target, and k gη is the gravity compensation coefficient related to the lead angle of the aircraft; Calculate the gravity compensation coefficient k according to the ballistic inclination angle θ gθ , and the formula is as follows: k gθ = cosθ Determine the threshold interval in which the ballistic inclination angle θ0 of the aircraft lies when it enters the terminal guidance stage, and further determine the gravity compensation coefficient related to the attack angle when the seeker captures the target The formula is as follows: Among them, k g1 , k g2 and k g3 are gravity compensation coefficients for different intervals, and θ1 and θ2 are ballistic inclination thresholds; Determine the threshold interval and positive / negative of the amplitude of the aircraft's lead angle η, and then adaptively adjust the gravity compensation coefficient k related to the aircraft's lead angle gη , The formula is as follows: where k gη11 , k gη12 , k gη21 , k gη22 , k gη31 , k gη32 and k gη4 are the gravity compensation coefficients for different intervals, and η1, η2 and η3 are the leading angle thresholds.

5. An adaptive gravity compensation trajectory correction method based on the lead angle according to claim 4, characterized in that: In S4, the combined guidance command a is calculated through the adaptive gravity compensation command a g and the proportional guidance command a yc with the following formula: y , as follows:

6. The adaptive gravity compensation trajectory correction method based on the lead angle according to claim 3, characterized in that: The proportionality coefficient N in S3 is 4.

7. An adaptive gravity compensation trajectory correction method based on the lead angle according to claim 2, characterized in that: In S2, the flight vehicle velocity vector lead angle η is calculated once every m frames of data are measured, where m is 20.

8. An adaptive gravity compensation ballistic correction method based on the lead angle according to claim 4, characterized in that: k in S4 g1 = 1.3, k g2 = 1, k g3 = 0.7, θ1 = -20, θ2 = -35.

9. An adaptive gravity compensation trajectory correction method based on the lead angle according to claim 4, characterized in that: k in S4 gη11 = 0.7, k gη12 = -0.5, k gη21 = 0.4, k gη22 = -0.3, k gη31 = 0.3, k gη32 = -0.2, k gη4 = 0, η1 = 10, η2 = 5, η3 = 3.

Images