A fast calculation method for missile target feasible region based on database

Abstract

The present invention discloses a database-based method for rapidly calculating the feasible domain of a missile target. The method comprises the following steps: establishing a missile glide phase motion equation; selecting a suitable prediction time step to divide the database into grid points; constructing a missile target feasible domain database using a D-V profile tracking method based on the database grid points; fitting the missile target feasible domain database information to obtain boundary point trajectories, and substituting the current prediction time into the boundary point trajectories to obtain the range of the current missile target feasible domain. By using the present invention, it is possible to ensure that the solution accuracy and computational efficiency of the missile target feasible domain meet the requirements of new combat technology indicators. As a database-based method and system for rapidly calculating the feasible domain of a missile target, the present invention can be widely applied to the field of missile flight dynamics trajectory planning.

Description

Technical Field

[0001] The invention relates to the technical field of missile flight dynamics trajectory planning, in particular to a database-based method for quickly solving a missile target feasible domain. Background Art

[0002] With the continuous development and improvement of various missile weapon defense systems, the penetration performance of missiles in traditional combat modes is facing severe challenges. During the glide phase of flight, if a missile encounters an abnormal event or sudden failure, it may need to deviate from the pre-planned trajectory and re-plan its flight path online. In such cases, it is necessary to quickly predict the reachable area based on the missile's current flight state and select the appropriate target point to provide a basis for ground-based countermeasures. Therefore, research on methods for rapidly calculating the feasible region of missile targets is of great value in shortening missile launch preparation time and improving missile survivability and strike effectiveness.

[0003] Currently, methods commonly used to solve the feasible domain of missile targets include the constant roll angle method, optimization methods, and profile design methods. The target feasible domain calculated using the constant roll angle method exhibits a certain degree of error, often being smaller than the actual feasible domain. While the optimization and profile design methods offer high accuracy, they are relatively slow. The accuracy and speed of current methods for solving the feasible domain of missile targets generally fail to meet the requirements of new operational technical indicators. Summary of the Invention

[0004] In order to solve the above technical problems, the object of the present invention is to provide a method and system for quickly solving the feasible domain of missile targets based on a database, which can improve the solution accuracy and calculation efficiency of the feasible domain of missile targets.

[0005] The first technical solution adopted by the present invention is: a method for quickly solving the feasible domain of missile targets based on a database, comprising the following steps:

[0006] Establish the missile's glide phase motion equation;

[0007] The predicted time of the missile glide phase is divided according to the preset time step to obtain the database grid points;

[0008] Based on the database grid points, the DV profile tracking method is used to track and design the missile glide phase motion equation and build a missile target feasible domain database.

[0009] The polynomial fitting method is used to fit the missile target feasible region database information to obtain the trajectory of the boundary point position changing with the prediction time;

[0010] Substitute the current predicted time into the trajectory of the boundary point position changing with the predicted time to obtain the range of the feasible region of the current missile target;

[0011] The new target point is judged based on the target feasibility judgment rule and the range of the feasible domain of the current missile target to obtain the judgment result.

[0012] Furthermore, by dividing the predicted time of the missile glide segment by selecting a suitable prediction time step, the grid points of the database are obtained. This is an optimal step, which unifies the prediction time step of each boundary point, so that the curve change trend can be more intuitively seen when the boundary point trajectory curve is subsequently fitted.

[0013] Furthermore, the step of tracking and designing the missile glide phase motion equation using the DV profile tracking method based on the database grid points to construct a missile target feasible domain database specifically includes:

[0014] Determine the maximum and minimum range profiles and select an unreachable virtual target point on the initial heading;

[0015] The maximum and minimum longitudinal range points of the missile are obtained using the DV profile tracking method;

[0016] According to the maximum range profile, by flying with a constant positive or negative bank angle sign, the maximum cross-range points on both sides under the maximum range condition are obtained;

[0017] According to the minimum range profile, by maintaining a constant positive or negative bank angle sign, the maximum range points on both sides under the minimum range condition are obtained;

[0018] The horizontal range points and the vertical range points are connected by fitting method to form a fan-shaped reachable area on the latitude and longitude plane;

[0019] The six feasible region boundary points under each database grid point state are calculated and connected to obtain the missile target feasible region database.

[0020] Through this optimization step, the feasible domain of the missile target and its boundary point positions under fixed time feature points are obtained, realizing the transformation from DV profile tracking to motion range coverage, and providing data support for fitting the trajectory of boundary point positions changing with prediction time.

[0021] Furthermore, the step of fitting the missile target feasible region database information using a polynomial fitting method to obtain a trajectory of the boundary point position changing with the prediction time specifically includes:

[0022] Taking the prediction time as the independent variable, select the appropriate polynomial equation for each boundary point;

[0023] The coefficients of the polynomial equation are solved based on the missile target feasible domain database information to obtain the trajectory of the boundary point position changing with the prediction time.

[0024] Through this preferred step, the changing trend of the boundary point trajectory curve can be intuitively observed, and the boundary point position information of the fixed time feature point is successfully extended to the boundary point position information of the entire prediction time.

[0025] Furthermore, the step of substituting the current predicted time into the trajectory of the boundary point position changing with the predicted time to obtain the range of the current missile target feasible region specifically includes:

[0026] Substitute the current prediction time into the trajectory equation of the boundary point position changing with the prediction time to obtain the coordinate position of each boundary point;

[0027] According to the coordinate position of each boundary point, the minimum range curve, maximum range curve, left boundary line and right boundary line are fitted to obtain the area surrounded by the boundary line, which is the range of the feasible domain of the current missile target.

[0028] Through this preferred step, the coordinate position of each boundary point at any prediction time node on the prediction time axis and the range of the feasible domain of the missile target can be obtained.

[0029] Furthermore, the step of judging the new target point based on the target feasibility judgment rule and the range of the current missile target feasible domain to obtain a judgment result specifically includes:

[0030] Substitute the latitude coordinates of the new target point into the minimum range curve and the maximum range curve to obtain the longitude boundary threshold;

[0031] Substitute the longitude coordinates of the new target point into the left lateral boundary line and the right lateral boundary line to obtain the latitude boundary threshold;

[0032] Determine whether the longitude and latitude coordinates of the new target point are within the longitude and latitude boundary thresholds to obtain a determination result.

[0033] Through this optimization step, it is judged whether the new target point is within the feasible domain of the current missile target, and subsequent combat techniques can be adopted according to the judgment result. If the new target point is reachable, the missile is continued to be controlled to fly to the new target point. If the new target point is unreachable, a new target point is replanned, and then it is judged whether the target point is within the feasible domain of the current missile target.

[0034] The beneficial effects of the method and system of the present invention are as follows: taking into account the problem that the accuracy and speed of the current missile target feasible domain solution method usually cannot meet the requirements of new combat technical indicators, the present invention adopts a method of establishing a target feasible domain database using prediction time as an independent variable, and fits the database information to the boundary point trajectory curve. By performing interpolation calculation on the boundary point trajectory curve, the missile target feasible domain range is obtained, thereby improving the missile target feasible domain solution accuracy and calculation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a flowchart of the steps of a method for quickly calculating a feasible domain of a missile target based on a database of the present invention;

[0036] Figure 2 It is a drag acceleration profile of a database-based missile target feasible domain rapid solution method of the present invention;

[0037] Figure 3 This is a schematic diagram of an azimuth error corridor of a database-based missile target feasible domain rapid solution method of the present invention;

[0038] Figure 4 This is a schematic diagram of a target feasible domain of a missile target feasible domain fast solution method based on a database of the present invention;

[0039] Figure 5 This is a schematic diagram of the change of the target reachable domain over time of a missile target feasible domain fast solution method based on a database of the present invention;

[0040] Figure 6 It is a boundary point position change trajectory diagram of a missile target feasible domain fast solution method based on a database of the present invention;

[0041] Figure 7 This is a schematic diagram of target feasibility judgment of a database-based missile target feasible domain fast solution method of the present invention; DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are provided for ease of description only and do not limit the order of the steps. The order of execution of the steps in the embodiments can be adaptively adjusted based on the understanding of those skilled in the art.

[0043] Reference Figure 1 The present invention provides a method for quickly calculating the feasible domain of a missile target based on a database, the method comprising the following steps:

[0044] S1. Establish the missile glide motion equation in the semi-velocity coordinate system, which is expressed as follows:

[0045]

[0046] Where v and θ are the velocity and velocity inclination of the missile relative to the earth, λ is the longitude, φ is the latitude, r is the distance from the center of the earth, σ is the track yaw angle, ρ is the atmospheric density, m is the mass of the missile, and S m is the reference area, ω e is the angular velocity of the Earth, g r ′ is the component of the earth's gravitational acceleration in the direction of the earth's center vector, is the component of the Earth’s gravitational acceleration in the direction of the Earth’s rotational angular velocity, C D is the lift coefficient, C L is the drag coefficient, C Z is the side force coefficient, and β is the roll angle.

[0047] Typical process constraints during the missile's glide phase include stagnation heat flux, dynamic pressure, and overload constraints. The heat flux constraint is to prevent aerodynamic thermal ablation, the dynamic pressure constraint is to prevent excessive air rudder hinge torque, and the overload constraint is mainly to prevent missile structural damage. Their expressions are as follows:

[0048]

[0049] Where k is a constant whose value is related to the missile, L and D represent lift and drag, ρ represents the atmospheric density, and n max represents the maximum normal overload constraint value, represents the maximum stagnation point heat flux constraint value, q max Represents the maximum dynamic pressure constraint value.

[0050] The control quantity constraints are also part of the process constraints, mainly including the amplitude and rate of change constraints of the missile's angle of attack and roll angle. That is, the amplitude and rate of change of the missile's angle of attack and roll angle must meet the following conditions:

[0051]

[0052] Where α represents the missile attack angle, α min Indicates the minimum amplitude of the missile's attack angle, α max represents the maximum amplitude of the missile's attack angle, β represents the missile's roll angle, and β min Indicates the minimum amplitude of the missile's roll angle, β max Indicates the maximum amplitude of the missile's roll angle, represents the rate of change of the missile's angle of attack, Indicates the rate of change of the missile's roll angle.

[0053] The terminal constraint mainly refers to the missile's altitude and speed at the end of the glide phase, that is, the missile's altitude and speed meet the following conditions:

[0054]

[0055] where v f Indicates the missile's altitude at the end of the glide phase, h f Indicates the missile speed at the end of the gliding phase, h * Indicates the missile's altitude at the end of the glide phase, v * Indicates the missile's speed at the end of the glide phase.

[0056] S2. Since the time of the aircraft abnormal event cannot be determined, it is necessary to establish a database using the predicted time as the independent variable. Select an appropriate prediction time step to divide the predicted time of the missile glide phase to obtain the grid points of the database.

[0057] In Specific Example 1, a time step of 200 seconds is selected, and the time feature points are divided starting from the glide segment starting time t = 0 seconds. In Specific Example 2, a time step of 100 seconds is selected, and the time feature points are divided starting from the glide segment starting time t = 0 seconds. In Specific Example 3, a time step of 500 seconds is selected, and the time feature points are divided starting from the glide segment starting time t = 0 seconds. Each time feature point is a grid point in the database. Based on the subsequent fitted boundary point position change trajectory, in Specific Example 1, it can be most intuitively seen that the aircraft's coverage area gradually decreases, and the positions of the six boundary points of the coverage area are related to the predicted time.

[0058] S3. Based on the database grid points, the DV profile tracking method is used to track and design the missile glide phase motion equation and build a missile target feasible domain database.

[0059] The DV profile tracking method includes the profile tracking guidance law design and the roll reversal logic design, and specifically includes the following steps:

[0060] Confirm the process constraints such as stagnation heat flux density constraint, dynamic pressure constraint and overload constraint that the missile will be subject to during reentry. In the resistance acceleration-velocity corridor determined by the process constraints, the reference DV profile can be designed as a three-segment broken line according to the range requirements, such as Figure 2 The mathematical expression of the track corresponding to this profile is as follows:

[0061]

[0062] Once the reference DV profile is determined, the standard lift-to-drag ratio of the missile when it flies along this profile can be calculated. The mathematical expression is as follows:

[0063]

[0064] Where C1 and C2 are the design parameters of the section, h s is a constant and h s =7110m, g is the acceleration due to gravity.

[0065] The lift-to-drag ratio increment is designed based on the longitudinal guidance task. Since the longitudinal guidance task is to make the aircraft fly along the reference profile as much as possible, and to ensure a good transition during the guidance process, the mathematical expression of the designed lift-to-drag ratio increment is as follows:

[0066]

[0067] The sum of the lift-to-drag ratio increment and the standard lift-to-drag ratio is the lift-to-drag ratio required for longitudinal guidance. The lift-to-drag ratio required for longitudinal guidance guides the missile to the preset target point. The calculation formula is as follows:

[0068]

[0069] Among them, D0, D f is the initial drag acceleration of the gliding section, and V1, V2, and D1 are the design values ​​of the drag acceleration profile.

[0070] After obtaining the lift-to-drag ratio required for longitudinal guidance, the roll angle of the aircraft is obtained by inverse solution, so that the aircraft can track the designed drag acceleration profile. Assume that the current position of the aircraft is (λ, φ), relative to the target point (λ * ,φ * ) is the sight angle ψ LOS , which represents the angle between the line of sight (from the aircraft to the target point) and the true north direction. The calculation formula is:

[0071]

[0072] Define the azimuth error as Δψ=Ψ T -ψ LOS , where Ψ T is the velocity azimuth. The azimuth error corridor tilt reversal logic is: when the azimuth error value is within the error corridor |Δψ|≤|Δψ max |, the roll angle sign remains unchanged; when the azimuth error value exceeds the upper boundary of the error corridor |Δψ|≥|Δψ max |, that is, the trajectory deflects, and the sign of the roll angle changes. The azimuth error corridor is a man-made broken line that shows the azimuth error changing with speed. The schematic diagram of the azimuth error corridor is as follows: Figure 3 shown.

[0073] like Figure 4 As shown, the upper boundary of the DV profile is determined by the stagnation heat flux density, overload, and dynamic pressure constraints of the gliding section, and the lower boundary is determined by the quasi-equilibrium gliding condition;

[0074] The maximum and minimum range sections are determined based on the upward and downward displacement of the section. Moving the section upward decreases the range, while moving the section downward increases the range. If the designed section touches the upper boundary, it is the minimum range section; if the designed section touches the lower boundary, it is the maximum range section.

[0075] Based on the determined maximum and minimum range profiles, an unreachable point is first selected in the flight direction and used in conjunction with the bank reversal logic to determine the aircraft's flight direction. The determined maximum range profile is then combined with the DV profile tracking method to determine the aircraft's range, yielding the missile's maximum longitudinal range point 5 and minimum longitudinal range point 2.

[0076] According to the maximum range profile, by maintaining a constant positive or negative bank angle, the maximum range points on both sides under the maximum range condition are obtained, namely the maximum range point 4 on the left side of the maximum range and the maximum range point 6 on the right side of the maximum range.

[0077] According to the minimum range profile, by maintaining a constant positive or negative bank angle, the maximum range points on both sides under the minimum range condition are obtained, namely the maximum range point 1 on the left side of the minimum range and the maximum range point 3 on the right side of the minimum range.

[0078] The six boundary points are connected by a fitting method to form a fan-shaped reachable domain on the latitude and longitude plane. The fitting method is consistent with the minimum range curve, maximum range curve, left lateral boundary line and right lateral boundary line fitting method in S5. The maximum longitudinal range point 5, the minimum longitudinal range point 2, the maximum horizontal range point 1 on the left side of the minimum range, the maximum horizontal range point 4 on the left side of the maximum range, the maximum horizontal range point 3 on the right side of the minimum range and the maximum horizontal range point 6 on the right side of the maximum range are the coordinate positions of the boundary points in S5.

[0079] Calculate the six feasible domain boundary points under each database grid point state and connect them to obtain the missile target feasible domain database. The missile target feasible domain database is as follows: Figure 5 As shown in FIG, as the aircraft prediction time goes by, the coverage area of ​​the aircraft gradually decreases, and the positions of the six boundary points of the coverage area are related to the prediction time.

[0080] S4, such as Figure 6 As shown in the figure, the polynomial fitting method is used to fit the missile target feasible domain database information to obtain the trajectory of the boundary point position changing with the prediction time.

[0081] The appropriate polynomial equation is selected for each boundary point with the prediction time as the independent variable. The mathematical expression of the polynomial equation is as follows:

[0082]

[0083]

[0084] Where i represents the i-th boundary point, i=1,2,…,6; t p represents the prediction time, λ represents longitude, φ represents latitude; n represents the dimension of polynomial interpolation, n=0,1,…,N; a n and bn Represents the coefficients of the polynomial interpolation.

[0085] The position information of each boundary point of the fixed time feature point in the missile target feasible domain database is substituted into the polynomial equation of each boundary point, and the coefficients of the polynomial equation are solved using the least squares method. The curve represented by the obtained polynomial equation is the trajectory of the boundary point position changing with the predicted time.

[0086] S5. Substitute the current predicted time into the trajectory of the boundary point position changing with the predicted time to obtain the range of the feasible region of the current missile target.

[0087] Substituting any predicted time into the trajectory equation of the boundary point position changing with the predicted time, the coordinate position of each boundary point of the target feasible region corresponding to the predicted time can be quickly solved;

[0088] The minimum range curve, maximum range curve, left side boundary line, and right side boundary line are fitted based on the coordinate positions of each boundary point. The minimum range curve, maximum range curve, left side boundary line, and right side boundary line are connected to obtain the boundary line enclosed area, which is the range of the current missile target feasible region. The mathematical expressions for fitting the minimum range curve, maximum range curve, left side boundary line, and right side boundary line are as follows:

[0089]

[0090] Where l1 is the minimum range curve, l2 is the maximum range curve, l3 is the left lateral boundary line, l4 is the right lateral boundary line, a1, a2, b1, b2, c1 and c2 are polynomial coefficients, which can be determined by polynomial fitting, λ4 is the longitude of boundary point No. 4, φ4 is the latitude of boundary point No. 4, λ1 is the longitude of boundary point No. 1, φ1 is the latitude of boundary point No. 1, λ6 is the longitude of boundary point No. 6, φ6 is the latitude of boundary point No. 6, λ3 is the longitude of boundary point No. 3, and φ3 is the latitude of boundary point No. 3.

[0091] S6, such as Figure 7 As shown in FIG, based on the target feasibility judgment rule and the range of the feasible domain of the current missile target, the new target point is judged to obtain the judgment result.

[0092] Assume that the position of the new target point is (λ t ,φ t ), substitute the latitude coordinates of the new target point into the minimum range curve and the maximum range curve to obtain the minimum longitude value a1φ t 2 +b1φ t +c1, maximum longitude value a2φ t 2 +b2φ t +c2,[a1φ t2 +b1φ t +c1, a2φt2+b2φt+t2 is the longitude boundary threshold. Substitute the longitude coordinates of the new target point into the left and right lateral boundary lines to obtain the minimum latitude value Maximum latitude value That is the latitude boundary threshold;

[0093] Determine whether the longitude and latitude coordinates of the new target point are within the longitude and latitude boundary thresholds. If the longitude and latitude of the new target point meet the judgment conditions, the target point is considered reachable, otherwise it is considered unreachable. The expression of the judgment condition is as follows:

[0094]

[0095] Among them, a1, a2, b1, b2, c1 and c2 are polynomial coefficients, which can be determined by polynomial fitting. λ4 is the longitude of boundary point No. 4, φ4 is the latitude of boundary point No. 4, λ1 is the longitude of boundary point No. 1, φ1 is the latitude of boundary point No. 1, λ6 is the longitude of boundary point No. 6, φ6 is the latitude of boundary point No. 6, λ3 is the longitude of boundary point No. 3, φ3 is the latitude of boundary point No. 3, λ t is the longitude of the new target point, φ t is the latitude of the new target point.

[0096] If the new target point is judged to be reachable, the missile will continue to be controlled to fly to the new target point to achieve a precise strike on the new target point. If the new target point is judged to be unreachable, the command center needs to re-plan a target point and then re-judge whether the target point is within the feasible range of the current missile target.

[0097] The contents of the above method embodiments are all applicable to the present system embodiments. The functions specifically implemented by the present system embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0098] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A database-based method for quickly calculating the feasible region of missile targets, characterized in that: The following steps are involved: S1), establish the missile glide phase motion equation; S2), dividing the predicted time of the missile glide segment according to a preset time step to obtain database grid points; S3) Based on the database grid points, the DV profile tracking method is used to track and design the missile glide phase motion equation, and a missile target feasible domain database is constructed; The DV profile tracking method includes profile tracking guidance law design and roll reversal logic design, which specifically includes: Based on the range requirements, a reference DV profile is designed in the drag acceleration-velocity corridor determined by the process constraints; According to the reference DV profile, the standard lift-to-drag ratio of the aircraft when flying along the profile is solved; The lift-to-drag ratio increment is designed according to the longitudinal guidance mission, and the required lift-to-drag ratio is obtained by combining the standard lift-to-drag ratio. The missile is guided to the pre-set target point by the required lift-to-drag ratio through longitudinal guidance; Calculate the sight azimuth according to the current position of the missile and the position of the target point; The azimuth error is defined as the difference between the velocity azimuth and the line of sight azimuth; Determine the roll angle sign based on the relationship between the azimuth error and the azimuth error corridor; Construct a missile target feasible domain database, including: Determine the maximum and minimum range profiles and select an unreachable virtual target point on the initial heading; The maximum and minimum longitudinal range points of the missile are obtained using the DV profile tracking method; According to the maximum range profile, by flying with a constant positive or negative bank angle sign, the maximum cross-range points on both sides under the maximum range condition are obtained; According to the minimum range profile, by maintaining a constant positive or negative bank angle sign, the maximum range points on both sides under the minimum range condition are obtained; The horizontal range points and the vertical range points are connected by fitting method to form a fan-shaped reachable area on the latitude and longitude plane; Calculate the six feasible region boundary points under each database grid point state and connect them to obtain the missile target feasible region database; S4), using a polynomial fitting method to fit the missile target feasible domain database information, and obtain the trajectory of the boundary point position changing with the prediction time; S5) Substitute the current predicted time into the trajectory of the boundary point position changing with the predicted time to obtain the range of the feasible region of the current missile target.

2. The method for quickly calculating the feasible region of a missile target based on a database according to claim 1, wherein: Also includes: S6) Based on the target feasibility judgment rule and the range of the current missile target feasible domain, the new target point is judged to obtain a judgment result.

3. The method for quickly calculating the feasible region of a missile target based on a database according to claim 1, characterized in that: The missile glide phase motion equation is expressed as follows: Where v and θ are the velocity and velocity inclination of the missile relative to the earth, λ is the longitude, φ is the latitude, r is the distance from the center of the earth, σ is the track yaw angle, ρ is the atmospheric density, m is the mass of the missile, and S m is the reference area, ω e is the angular velocity of the Earth, g r ′ is the component of the earth's gravitational acceleration in the direction of the earth's center vector, is the component of the Earth’s gravitational acceleration in the direction of the Earth’s rotational angular velocity, C D is the lift coefficient, C L is the drag coefficient, C Z is the side force coefficient, and β is the roll angle.

4. The method for quickly calculating the feasible region of a missile target based on a database according to claim 1, wherein: The step of fitting the missile target feasible domain database information using a polynomial fitting method to obtain a trajectory of the boundary point position changing with the prediction time specifically includes: With the prediction time as the independent variable, a polynomial equation is selected for each boundary point; The coefficients of the polynomial equation are solved based on the missile target feasible domain database information to obtain the trajectory of the boundary point position changing with the prediction time.

5. The method for quickly calculating the feasible region of a missile target based on a database according to claim 1, wherein: The trajectory of the boundary point position changing with the prediction time is expressed as follows: Where i represents the i-th boundary point, i=1,2,…,6; t p represents the prediction time, λ represents longitude, φ represents latitude; n represents the dimension of polynomial interpolation, n=0,1,…,N; a n and b n Represents the coefficients of the polynomial interpolation.

6. The method for quickly calculating the feasible region of a missile target based on a database according to claim 1, wherein: The step of substituting the current predicted time into the trajectory of the boundary point position changing with the predicted time to obtain the range of the current missile target feasible region specifically includes: Substitute the current prediction time into the trajectory equation of the boundary point position changing with the prediction time to obtain the coordinate position of each boundary point; According to the coordinate position of each boundary point, the minimum range curve, maximum range curve, left boundary line and right boundary line are fitted to obtain the area surrounded by the boundary line, which is the range of the feasible domain of the current missile target.

7. The method for quickly calculating the feasible region of a missile target based on a database according to claim 2, wherein: The step of judging the new target point based on the target feasibility judgment rule and the range of the current missile target feasible domain to obtain the judgment result specifically includes: Substitute the latitude coordinates of the new target point into the minimum range curve and the maximum range curve to obtain the longitude boundary threshold; Substitute the longitude coordinates of the new target point into the left lateral boundary line and the right lateral boundary line to obtain the latitude boundary threshold; Determine whether the longitude and latitude coordinates of the new target point are within the longitude and latitude boundary thresholds to obtain a determination result.

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