A maneuvering target interception guidance method with arrival angle and field of view angle constraints

Abstract

The present invention discloses a method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints, comprising: establishing a relative motion equation for an aircraft to intercept a maneuvering target; converting the relative motion equation into a relative motion model with the distance between the aircraft and the target as an independent variable; setting a desired relative lead angle variation curve, and obtaining a guidance law expression based on the relative motion model; performing field of view angle constraints by limiting the maximum value of the relative lead angle curve to obtain a reachable range of the arrival angle; and when the arrival angle satisfies the reachable range, the aircraft uses the obtained guidance law for flight control. The method disclosed by the present invention does not require linear approximation processing of the mathematical model of the relative motion between the aircraft and the target, does not require the assumption of a small lead angle, and has the characteristics of simple design and use, strong applicability, and the like.

Description

Technical Field

[0001] The invention relates to a maneuvering target interception guidance method with arrival angle and field angle constraints, belonging to the technical field of aircraft control. Background Art

[0002] The primary task of the guidance law is to guide a vehicle to successfully intercept a target with zero miss distance. Currently, in some missions, to improve the probability of interception and the effectiveness of the strike, it is necessary to constrain the angle of arrival. Furthermore, when tracking a maneuvering target, the vehicle's target detector must maintain a constant lock on the target to prevent it from escaping the detector's field of view. This requires limiting the vehicle's field of view angle during guidance to within the target detector's maximum field of view, a process known as a field of view angle constraint.

[0003] Existing guidance methods with angle-of-arrival and field-of-view constraints typically require linearizing the mathematical model describing the relative motion between the vehicle and target, or assuming that the lead angle can be maintained near zero during the guidance process. Naturally, guidance methods designed based on these approximate assumptions have limitations. When these assumptions are not met, guidance performance inevitably degrades.

[0004] Therefore, it is necessary to conduct more in-depth research on the maneuvering target interception guidance method to solve the above problems. Summary of the Invention

[0005] In order to overcome the above problems, the inventors have conducted in-depth research and proposed a maneuvering target interception guidance method with arrival angle and field of view angle constraints, preferably comprising the following steps:

[0006] S1. Establish the relative motion equations for the aircraft to intercept the maneuvering target;

[0007] S2. Convert the relative motion equation into a relative motion model with the distance between the aircraft and the target as the independent variable;

[0008] S3. Setting a desired relative lead angle variation curve and obtaining a guidance law expression based on the relative motion model;

[0009] S4. The field of view angle is constrained by limiting the maximum value of the relative lead angle curve, thereby obtaining a reachable range of the arrival angle. When the arrival angle satisfies the reachable range, the aircraft uses the obtained guidance law for flight control.

[0010] In a preferred embodiment, in S1, the relative motion equation of the aircraft intercepting the maneuvering target is expressed as:

[0011]

[0012] Among them, R represents the distance between the aircraft and the target, V M is the flight speed of the aircraft, V T is the flight speed of the maneuvering target, γ M is the trajectory inclination angle of the aircraft, γ T is the target's ballistic inclination angle, λ is the sight angle, σ M is the field of view of the aircraft, and satisfies the field of view constraint σ max is the maximum field of view angle, a M is the normal acceleration of the aircraft, a T is the normal acceleration of the target.

[0013] In a preferred embodiment, in S2, the relative motion equation is converted into a relative motion model with the distance between the aircraft and the target as the independent variable by setting relative variables.

[0014] In a preferred embodiment, the relative variable is set to:

[0015] K=V T / V M

[0016] γ R =arctan[(sinγ M -Ksinγ T ) / (cosγ M -Kcosγ T )]

[0017]

[0018] a R =a M cos(γ M -γ R )-a T cos(γ T -γ R )

[0019] Where K is the speed ratio, γ R ,η R 、V R 、a R Represent the relative inclination angle, relative lead angle, relative velocity and relative acceleration respectively, and there is

[0020]

[0021] In a preferred embodiment, the relative motion model is expressed as:

[0022]

[0023] In a preferred embodiment, in S3, a cubic function with the distance R as the independent variable is set as the desired relative lead angle variation curve, which is expressed as:

[0024]

[0025] Among them, R0 is the initial relative distance between the aircraft and the target, is the desired relative lead angle to be designed, and a, b, c, and d are design parameters determined by boundary conditions and arrival angle constraints.

[0026] In a preferred embodiment, the guidance law expression obtained is:

[0027]

[0028] In a preferred embodiment, in S4, the field of view angle constraint can be converted into a limit on the maximum value of the relative lead angle, which can be expressed as:

[0029]

[0030] Among them, η max Indicates the maximum value of the relative lead angle curve,

[0031] The constraint of the design parameter a is obtained based on the maximum value of the relative lead angle:

[0032] Γ a ={a|a min ≤a≤a max}

[0033] a min =κ1η max

[0034] a max =κ2η max

[0035] x=η R0 / η max

[0036]

[0037] Among them, Γ a Represents the constraint of design parameter a, a min Indicates the minimum value of the design parameter a, a max Indicates the maximum value of the design parameter a, κ1, κ2, x, κ 21 , κ 22 is an intermediate parameter.

[0038] In a preferred embodiment, the reachable range λ of the arrival angle d Expressed as:

[0039] λ min ≤λ d ≤λ max

[0040]

[0041]

[0042] Among them, λ max represents the maximum value of the arrival angle, λ min Indicates the minimum value of the arrival angle.

[0043] The beneficial effects of the present invention include:

[0044] (1) Unlike existing guidance methods for intercepting maneuvering targets, the present invention does not require linear approximation of the mathematical model of the relative motion between the aircraft and the target during the design process, and does not require the assumption of a small lead angle;

[0045] (2) The designed analytical guidance law has a simple design method and strong engineering practicality. While achieving accurate interception of maneuvering targets, it can meet the arrival angle and target detector field of view constraints. It is suitable for guidance tasks with arrival angle constraints and target detector field of view restrictions.

[0046] (3) There is no need to linearize the mathematical model of the relative motion between the aircraft and the target, and there is no need to repeatedly try out the guidance parameters. It has the characteristics of simple design and use methods and strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic flow chart of a maneuvering target interception and guidance method with arrival angle and field of view angle constraints according to a preferred embodiment of the present invention is shown;

[0048] Figure 2 The simulation results of Example 1 are shown. DETAILED DESCRIPTION

[0049] The present invention will be described in further detail below with reference to the accompanying drawings and examples, through which the features and advantages of the present invention will become more clearly understood.

[0050] The word "exemplary" is used exclusively herein to mean "serving as an example, example, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0051] According to the present invention, a maneuvering target interception guidance method with arrival angle and field angle constraints is provided. Figure 1 As shown, the following steps are included:

[0052] S1. Establish the relative motion equations for the aircraft to intercept the maneuvering target;

[0053] S2. Convert the relative motion equation into a relative motion model with the distance between the aircraft and the target as the independent variable;

[0054] S3. Setting a desired relative lead angle variation curve and obtaining a guidance law expression based on the relative motion model;

[0055] S4. The field of view angle is constrained by limiting the maximum value of the relative lead angle curve, thereby obtaining a reachable range of the arrival angle. When the arrival angle satisfies the reachable range, the aircraft uses the obtained guidance law for flight control.

[0056] In S1, the relative motion equation of the aircraft intercepting the maneuvering target is expressed as:

[0057]

[0058] σ M =γ M -λ

[0059]

[0060] Among them, R represents the distance between the aircraft and the target, V M is the flight speed of the aircraft, V T is the flight speed of the maneuvering target, γ M is the trajectory inclination angle of the aircraft, γ T is the target's ballistic inclination angle, λ is the line of sight angle, that is, the angle between the line between the target and the aircraft and the horizontal plane, σ M is the field of view of the aircraft, and satisfies the field of view constraint σ max is the maximum field of view angle, a M is the normal acceleration of the aircraft, a T is the normal acceleration of the target.

[0061] In S2, by setting relative variables, the relative motion equation is converted into a relative motion model with the distance between the aircraft and the target as the independent variable.

[0062] Specifically, the relative variable is set to:

[0063] K=V T / V M

[0064] γR =arctan[(sinγ M -Ksinγ T ) / (cosγ M -Kcosγ T )]

[0065]

[0066] a R =a M cos(γ M -γ R )-a T cos(γ T -γ R )

[0067] Where K is the speed ratio, γ R ,η R 、V R 、a R Represent the relative inclination angle, relative lead angle, relative velocity and relative acceleration respectively, and there is

[0068]

[0069] Combined with the relative motion equation, we can get:

[0070]

[0071] η R =γ R -γ M +σ M

[0072] η R |=γ R -γ M +σ M |≤γ R -γ M |+|σ M |≤η max

[0073]

[0074] Furthermore, taking the distance between the aircraft and the target as the independent variable, the above formula can be transformed into a relative motion model:

[0075]

[0076] In S3, a cubic function with distance R as the independent variable is set as the desired relative lead angle variation curve, which is expressed as:

[0077]

[0078] Among them, R0 is the initial relative distance between the aircraft and the target, is the desired relative lead angle to be designed, and a, b, c, and d are design parameters determined by boundary conditions and arrival angle constraints.

[0079] In the present invention, the relative lead angle is set to a cubic function in order to intercept a maneuvering target, which can effectively improve the interception stability of the maneuvering target, reduce the parameter complexity, and improve the parameter applicability.

[0080] Furthermore, the desired relative lead angle variation curve has boundary conditions, which are expressed as:

[0081]

[0082] Among them, η R0 is the relative lead angle at the time of interception, and |η R0 |≤η max .

[0083] Combining the boundary conditions with the desired relative lead angle variation curve, we can obtain:

[0084]

[0085] Combined with the first equation in the relative motion model, we can get:

[0086] λ d =H(a)

[0087]

[0088] Among them, λ0 is the initial line of sight angle, that is, the line of sight angle at the beginning of interception.

[0089] According to the present invention, λ0, η R0 , R0 are known quantities, when the expected arrival angle λ d Once specified, the parameter a can be obtained by solving the above equation using a common numerical algorithm (such as Newton's iteration method).

[0090] Combined with the relative motion model, the guidance law expression is obtained as follows:

[0091]

[0092] In S4, the field of view angle constraint can be converted into a limit on the maximum value of the relative lead angle, which is expressed as:

[0093]

[0094] Among them, η max Indicates the maximum value of the relative lead angle curve.

[0095] Solving the above inequality, we can get:

[0096] Γ a ={a|a min ≤a≤a max}

[0097] a min =κ1η max

[0098] a max =κ2η max

[0099] x=η R0 / η max

[0100]

[0101] Among them, Γ a represents the safe value range of the design parameter a, Γ a Any value in can ensure that the field of view angle constraint is satisfied, a min Indicates the minimum value of the design parameter a, a max Indicates the maximum value of the design parameter a, κ1, κ2, x, κ 21 , κ 22 is an intermediate parameter.

[0102] Furthermore, combined with the relative motion model, the reachable range λ of the arrival angle can be obtained d , expressed as:

[0103] λ min ≤λ d ≤λ max

[0104]

[0105] Among them, λ max represents the maximum value of the arrival angle, λ min Indicates the minimum value of the arrival angle.

[0106] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved. This is not limited herein.

[0107] Example

[0108] Example 1

[0109] Conduct a simulation experiment to intercept a maneuvering target, including the following steps:

[0110] S1. Establish the relative motion equations for the aircraft to intercept the maneuvering target;

[0111] S2. Convert the relative motion equation into a relative motion model with the distance between the aircraft and the target as the independent variable;

[0112] S3. Setting a desired relative lead angle variation curve and obtaining a guidance law expression based on the relative motion model;

[0113] S4. The field of view angle is constrained by limiting the maximum value of the relative lead angle curve to obtain a reachable range of the arrival angle. When the arrival angle satisfies the reachable range, the aircraft uses the obtained guidance law for flight control.

[0114] In S1, the relative motion equation of the aircraft intercepting the maneuvering target is expressed as:

[0115]

[0116] σ M =γ M -λ

[0117]

[0118] In S2, the relative motion model is:

[0119]

[0120] In S3, a cubic function with distance R as the independent variable is set as the desired relative lead angle variation curve, which is expressed as:

[0121]

[0122] The obtained guidance law expression is:

[0123]

[0124] In S4, the reachable range λ of the arrival angle can be obtained d , expressed as:

[0125] λ min ≤λ d ≤λ max

[0126]

[0127] in,

[0128] a min =κ1η max

[0129] a max =κ2η max

[0130] x=η R0 / η max

[0131]

[0132] During the simulation, three aircraft are set to intercept the target. The terminal arrival angles of the three aircraft are set to 20 degrees, 40 degrees, and 60 degrees respectively. The flight speed of the aircraft is set to 500 m / s, the initial position of the aircraft is (0, 5) km, the initial position of the maneuvering target is (10, 15) km, the flight speed is 350 m / s, the maximum field of view angle of the aircraft target detector is limited to 70 degrees (deg), and the acceleration of the target is set to -50 m / s. 2 .

[0133] The simulation results are as follows Figure 2 As shown, Figure 2 (a) shows the flight trajectories of the aircraft and the target; Figure 2 (b) shows the variation trend of the normal acceleration of the aircraft; Figure 2 (c) shows the changing trend of the aircraft's sight angle; Figure 2 (d) shows the changing trend of the aircraft's field of view angle.

[0134] It can be seen that the aircraft can successfully intercept the maneuvering target at the desired arrival angle, and ensure that the aircraft's field of view angle is always smaller than the set maximum field of view angle of the aircraft target detector during the guidance process.

[0135] The present invention has been described above with reference to preferred embodiments, but these embodiments are merely exemplary and serve only as illustrations. On this basis, various replacements and improvements can be made to the present invention, all of which fall within the scope of protection of the present invention.

Claims

1. A maneuvering target interception guidance method with arrival angle and field of view angle constraints, characterized in that: The following steps are involved: S1. Establish the relative motion equations for the aircraft to intercept the maneuvering target; S2. Convert the relative motion equation into a relative motion model with the distance between the aircraft and the target as the independent variable; S3. Setting a desired relative lead angle variation curve and obtaining a guidance law expression based on the relative motion model; S4. Constraining the field of view angle by limiting the maximum value of the relative lead angle curve, thereby obtaining a reachable range of the arrival angle. When the arrival angle satisfies the reachable range, the aircraft uses the obtained guidance law for flight control. In S3, a cubic function with distance R as the independent variable is set as the desired relative lead angle variation curve, which is expressed as: Among them, R represents the distance between the aircraft and the target, R0 is the initial relative distance between the aircraft and the target, is the desired relative lead angle to be designed, a, b, c, d are design parameters determined by boundary conditions and arrival angle constraints; The obtained guidance law expression is: Among them, a M is the normal acceleration of the aircraft, a T is the normal acceleration of the target, γ R ,η R 、V R Respectively represent the relative inclination angle, relative lead angle, relative speed, γ M is the trajectory inclination angle of the aircraft, γ T is the target's ballistic inclination angle, η R0 is the relative lead angle at the start of interception.

2. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 1, characterized in that: In S1, the relative motion equation of the aircraft intercepting the maneuvering target is expressed as: s M =c M -l Among them, V M is the flight speed of the aircraft, V T is the flight speed of the maneuvering target, λ is the sight angle, σ M is the field of view of the aircraft, and satisfies the field of view constraint σ max is the maximum field of view angle.

3. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 1, characterized in that: In S2, by setting relative variables, the relative motion equation is converted into a relative motion model with the distance between the aircraft and the target as the independent variable.

4. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 3, characterized in that: The relative variables are set to: K=V T / V M c R =arctan[(sinγ M -Ksing T ) / (cosγ M -Kcosγ T )] a R =a M cos(γ M -c R )-a T cos(γ T -c R ) Among them, K is the speed ratio, a R represents the relative acceleration, and 5. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 4, characterized in that: The relative motion model is expressed as:

6. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 2, characterized in that: In S4, the field of view angle constraint can be converted into a limit on the maximum value of the relative lead angle, which is expressed as: R∈[0, R0] Among them, η max Indicates the maximum value of the relative lead angle curve, The constraint of the design parameter a is obtained based on the maximum value of the relative lead angle: C a ={a|a min ≤a≤a max } a min =κ1η max a max =k2h max x=η R0 / or max Among them, Γ a Represents the constraint of design parameter a, a min Indicates the minimum value of the design parameter a, a max Indicates the maximum value of the design parameter a, κ1, κ2, x, κ 21 , κ 22 is an intermediate parameter.

7. The method for intercepting and guiding a maneuvering target with arrival angle and field of view angle constraints according to claim 6, characterized in that: The reach range of the arrival angle λ d Expressed as: l min ≤λ d ≤λ max Among them, λ max represents the maximum value of the arrival angle, λ min Indicates the minimum value of the arrival angle.

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