KR20130087307A - Trajectory correction method for artillery projectiles - Google Patents

Abstract

PURPOSE: A method for correcting a trajectory of a shell is provided to save kinetic energy due to maintaining an arc shape of flight path by generating a small inducement command even when there is a hitting error. CONSTITUTION: A method for correcting a trajectory of a shell includes the following steps: measuring flight data of a launched shell (S110); calculating a path correction angle which is defined as an interval angle between a present speed produced as measured flight data and a speed of the shell heading for a target (S200); calculating an induced acceleration command in order to control a canard wing with the calculated correction angle (S300); and operating the canard wing by delivering the calculated induced acceleration command to a control unit (S400). [Reference numerals] (AA) Start; (BB) End; (S110) Measure flight data; (S120) Is it a target of a launched shell?; (S200) Calculate a path correction angle; (S300) Calculate an induced acceleration command; (S400) Control a canard

Description

Trajectory Correction Method for Artillery Projectiles

The present invention relates to a method for correcting a ballistic trajectory, and more particularly, to a method for correcting a trajectory of a shell which can improve the hit rate of the trajectory by controlling a canad of a trajectory correcting apparatus for modifying the trajectory of the shell with a guided acceleration command. .

In general, shells fired from the ground by artillery, rockets, rotating barrels, etc., are filled with high explosives inside the body, and the lower part is equipped with a penetrator for penetrating armor (eg armored vehicles or tanks), and kills horses. Used for dual purposes such as armor penetrating.

In addition, the shell is equipped with a fuse to the nose portion of the shell as a means for detonating the high explosives, such as the fuse is used by a mechanical fuse that is exploded by the impact force generated when the target or the ground collides with.

On the other hand, traction guns and self-propelled artillery fire using a rotationally stable shell.

Rotating stabilized shells have a CEP of 0.6-1% of their range when they hit the ground due to various factors. Many devices and methods have been proposed to reduce these impact errors.

The rotationally stable shell is equipped with a ballistic correction device having a canad in the nose portion of the shell to replace the existing fuse.

The ballistic correction device controls the trajectory of the shell by controlling the trajectory of the shell by the control of the two axis canard wings mounted on the nose portion of the shell to adjust the impact point to the target in the two-dimensional space of the cross direction and the bias direction Improve the error

In general, missiles are used through the proportional navigation guidance method to improve impact error and accuracy.However, the proportional navigation guidance method generates an acceleration command even when there is no impact error due to the change in the angle of view that occurs during flight. However, the flight path created by the acceleration command is also not applicable to shells.

In addition, the proportional navigation guidance technique is not applicable because it generates an unwanted induced acceleration command when applied to a shell having a parabolic flight trajectory.

For example, even if the shell is aimed exactly at the target, the proportional navigation guidance method has a problem of generating a guidance command.

The present invention provides a method of correcting a ballistic trajectory that has a parabolic flight trajectory so as to minimize hitting error of a shell facing a target so that the target hits the target accurately.

The object of the present invention is a method of modifying the trajectory by adjusting the canard wings mounted on the shell with a controller,

A flight data measurement step of measuring flight data of the fired shell;

A path correction angle calculation step of calculating a path correction angle defined by an angle between a current speed derived from the measured flight data and a speed toward the target;

An acceleration command calculation step of calculating an induced acceleration command for controlling the canard wing with the calculated path correction angle; And

It is solved by providing a method of modifying the trajectory of the shell, including a wing control step of manipulating the canard wing by passing the calculated guided acceleration command to the controller.

The ballistic correction method of the shell according to the present invention calculates the acceleration command using the path correction angle defined as the angle between the current speed and the speed toward the target, instead of the change in the viewing angle, so that the impact error of the shell having the parabolic flight trajectory is obtained. Minimizes and improves the accuracy of shells.

The ballistic correction method of the shell according to the present invention does not generate a guided acceleration command for correcting a flight path when there is no impact error, and generates a small parabolic flight path of a shell by generating only a small guide command even when there is an impact error. It is advantageous in terms of saving kinetic energy.

The ballistic correction method of the shell according to the present invention saves computation time because only the calculation by simple arithmetic operation is required, and there is an effect of reducing the cost because it does not need a high-performance computer to handle many calculations.

1 is a flow chart illustrating a method for correcting ballistics of a shell according to the present invention.
Figure 2 is a schematic diagram for explaining the path correction angle in the ballistic correction method of the shell according to the present invention
3 is a block diagram of a path correction angle calculation step according to the present invention.
4 is a flowchart illustrating a method for calculating a weighting matrix and a bias in a method for correcting ballistics according to the present invention.
5 is a comparative example of a method for correcting a trajectory of shells according to the present invention.
6 is a comparative example of a method for correcting a trajectory of shells according to the present invention.
7 to 8 are graphs showing the impact of the impact point and the actual impact point predicted during the flight of the shell through the weighting matrix and the bias in the method of ballistic correction of the shell according to the present invention
9 is a graph showing the flight path of the shell modified by the method of ballistic correction of the shell according to the present invention.
10 is a graph comparing the ballistic correction method of the shell according to the present invention with proportional guidance navigation;
11 is a graph showing the change of the impact point is modified through the ballistic correction method of the shell according to the present invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The ballistic correction method of the shell according to the present invention is a method of modifying a ballistic by adjusting a canard blade mounted on a nose portion of the shell with a controller in a shell equipped with a ballistic correction device that modifies the ballistic by controlling the canad.

Referring to FIG. 1, a method of correcting ballistics of a shell according to the present invention includes a flight data measuring step (S100) of measuring flight data of a fired shell.

The flight data measurement step (S100) includes a position coordinate of the X-axis and a Y-axis based on the firing point of the shell and a velocity vector and a velocity vector of the shell at the position coordinate.

In addition, the flight data measuring step (S100) is a sensor in the shell and the position and speed detection process for detecting the position and coordinates of the X-axis, Y-axis with respect to the launch point of the shell as a reference point and the shell in the corresponding position coordinates ( S110);

The method determines whether the detected position is the target impact point, and if the target impact point ends the ballistic correction, and if the target impact point includes the impact point determination process (S120).

That is, the flight data measurement step (S100) repeats the process of measuring the velocity and direction of the shell according to the position coordinates and position coordinates of the shell until the fired shell reaches the target impact point.

After the flight data measurement step S100, a path correction angle calculation step S200 of calculating a path correction angle using measured flight data is performed. The path correction angle is defined as the angle between the speed of the current shell and the speed towards the target. The path correction angle is used to calculate the predicted impact point predicted by the velocity vector at the current position of the shell and, if the target impact point is different, an acceleration command for correcting the velocity vector to a modified velocity vector to reach the target impact point. .

The acceleration command is calculated in the acceleration command calculation step S300.

The ballistic correction method of the shell according to the present invention includes a wing control step (S400) for controlling the operation of the canard wing by transmitting the acceleration command to the controller.

The wing control step (S400) is to manipulate the position of the canard wings to modify the velocity vector at the current position of the shell to a modified velocity vector to reach the target impact point.

의 속도 벡터를 갖는다면 목표 탄착점(30)의 위치로부터 Δx만큼의 오차를 갖는 예측 탄착점(20)에 도달하게 된다. Referring to Figure 2, it will be described in more detail the ballistic correction method of the shell according to the present invention. As shown in FIG. 2, the shell 10 is positioned at any point during the flight.

If the velocity vector of V 1 is reached, the predicted impact point 20 having an error of Δx is reached from the position of the target impact point 30.

The path correction angle ΔA includes a first path correction angle Δγ in the X-axis direction and a second path correction angle ψ in the Y-axis direction. The first path correction angle Δγ corrects the impact error Δx in the cross direction, and the second path correction angle ψ corrects the impact error Δy in the biasing direction.

의 속도 벡터가 요구된다. 상기

의 속도 벡터와 상기

의 속도 벡터의 사이 각도가 경로 수정각(Δγ)이며, 상기

의 속도 벡터를 상기

의 속도 벡터로 수정하기 위해서는 제 1 경로 수정각(Δγ)만큼의 각도를 변화시킬 수 있는 가속도 명령(a_z)이 필요한 것이다. 상기

의 속도 벡터에서 상기

의 속도 벡터로 한번에 변화시킬 수 없기 때문에 기설정된 시간(Δt) 동안 점진적으로 변화시키므로, 상기 가속도 명령(a_z)은 하기 수학식 1에 의해 계산된다.To reach the shell 10 at the target impact point 30

The velocity vector is required. remind

And the velocity vector of

The angle between the velocity vectors of is the path correction angle Δγ,

Remind the speed vector of

In order to correct the velocity vector, the acceleration command a _z capable of changing the angle by the first path correction angle Δγ is required. remind

From the velocity vector of

The acceleration command a _z is calculated by Equation 1 below because it cannot be changed at a time by the velocity vector of.

[Equation 1]

N: Induction Constant (Designer Designated)

ΔA: path correction angle (first path correction angle (Δγ) in the X axis direction or second path correction angle (ψ) in the Y axis direction)

Δt: preset vector change time

: 계측된 포탄의 현재 속도 벡터

: Current velocity vector of the measured shell

The path correction angle calculation step (S200) includes a predicted impact point calculation process (S210) of calculating position coordinates at which impact of the shell 10 is expected using a weighting matrix and a bias stored in a memory mounted in the ballistic correction device;

An impact error calculation process of calculating an impact error between the predicted impact point 20 and the target impact point 30 (S220);

Sensitivity matrix calculation that calculates the sensitivity change of the impact point using the small change amount of the path correction angle and the weighting matrix at the position of the current shell 10, and obtains the sensitivity matrix using the small change amount of the path correction angle and the small change amount of the impact point. The process (S230);

Comprising a path correction angle calculation step (S240) for calculating the path correction angle by using the sensitivity matrix. The sensitivity matrix calculation process is to calculate the sensitivity matrix using the small change amount (εγ, εψ) of the path correction angle and the small change amount (εx, εy) of the impact point, and is calculated using Equation 2 below.

&Quot; (2) "

εγ, εψ: minute change in path correction angle

εx, εy: minute change of impact point

,

,

,

: 민감도

,

,

,

Sensitivity

Each component of the sensitivity matrix of Equation 2 is called sensitivity, and is calculated as an amount of change of the impact point εx obtained through the prediction of the impact point with respect to the amount of change εγ of the first path correction angle. If the impact error Δx of the shell is small, it can be said that the first path correction angle is linearly changed in proportion to this, and the first path correction angle is expressed by Equation 3 using the sensitivity and the impact error of the shell. Is calculated.

&Quot; (3) "

: 민감도

Sensitivity

Δγ: first path correction angle

Δx: Impact error in the range

In addition, since the first path correction angle Δγ corrects the impact error Δx in the cross direction, and the second path correction angle ψ modifies the impact error Δy in the bias direction, Equation 3 When expanded in two dimensions, it is represented by the following formula (4).

&Quot; (4) "

Δγ: first path correction angle

Δψ: second path correction angle

Δx: Impact error in the range

Δy: impact error in the bias direction

,

,

,

: 민감도

,

,

,

Sensitivity

The path correction angle calculated by Equation 4 is substituted into Equation 1, respectively.

In other words, the induced acceleration command calculation step is calculated by substituting the path correction angle and the current velocity of the shell calculated by Equation 4 into Equation 1.

The induced acceleration command is transmitted to the controller, and the controller modifies the shell flight path by manipulating the canard wing with the received induced acceleration command.

On the other hand, an embodiment for calculating the path correction angle will be described in detail below.

The weighting matrix and bias stored in the memory of the ballistic correction device mounted on the shell consist of four layers.

In more detail, four weight matrices and bias sets for calculating impact errors in the cross direction and four weight matrices and bias sets for calculating impact errors in the deviation directions are stored in the memory.

Five flight states (altitude, rotational speed of the carcass, speed of three axes) are used as inputs, and the remaining distance from the current position in the direction of the firing range is calculated and outputted through the matrix calculation in all four layers of Equation 5 below. Finally, add the current position to calculate the expected impact point for the shell.

&Quot; (5) "

The three-dimensional coordinates of the launch point and the target are as follows.

(1) Coordinate of launch point: (0, 0, 0) m

(2) Coordinates of the target: (25712.31, 719.14, 0) m

The flight status information of the shell at the start of ballistic modification is as follows.

(1) Location: (15272.69, 125.84, 7850) m

(2) Speed: 1412.03 rad / sec

(3) Speed of 3 axes: (302.99, 8.21, 11.49) m / s

The calculation of impact error in the direction of the range uses five inputs:

(1) Input (5): altitude (7850m), rotational speed (1412.03rad / s), three-axis speed (302.99m / s, 8.21m / s, 11.49m / s)

(2) Output (1): Distance remaining from the current position in the downrange direction 10343.84m

(3) Expected impact coordinates: 25616.53m in the cross direction

(4) Impact error (expected impact coordinate-target coordinate): -95.78m

The impact error calculation in the crossrange direction is obtained using the other four layers with the same input.

(1) Output (1): Remaining distance from the current position in the crossrange direction (507.73m)

(2) Expected impact coordinates: 633.58 m in the direction of convenience

(3) Impact error (expected impact coordinate-target coordinate): -85.56m

Each layer uses the following equation (6), the matrix calculation formula.

&Quot; (6) "

이다. here,

to be.

W _i denotes a weight matrix in each layer, and b _i denotes a bias in each layer.

The weight matrix in the first layer is 6X5, the weight matrix in the second layer is 13X6, the weight matrix in the third layer is 7X13, and the weight matrix in the fourth layer is 1X7. to be. The size of the weighting matrix in each layer is the result of optimization by the designer for the shell used.

In the table below, which is calculated sequentially from four layers, the path correction angles (Δγ, Δψ) are obtained using the impact error (Δx) in the cross direction and the impact error (Δy) in the bias direction. The acceleration command (a _x , a _y ) can be calculated.

As shown in Table 1 below, the impact error of (-95.78, -85.56) m occurs at an altitude of 7850m, and the canad attached to the shell is moved by the generated guided acceleration command, and the ballistic correction is made. It can be seen that the lower the impact error gradually decreases.

H (m) 7850 7500 7000 6500 6000 5000 4000 P (rad / s) 1412.03 1385.06 1361.09 1342.35 1325.57 1294.49 1264.56 U (m / s) 302.99 284.59 273.28 264.04 255.31 238.34 221.69 V (m / s) 8.210 12.034 13.674 14.554 15.023 15.343 15.211 W (m / s) 11.49 80.38 123.50 153.62 177.45 213.60 240.14 Δx -95.776 -29.897 -14.192 -7.654 -4.842 -2.815 0.781 Δy -85.562 -26.651 -11.927 -5.060 -1.909 0.320 -0.184 Δγ 0.702 0.218 0.107 0.061 0.042 0.029 -0.010 Δψ 0.503 0.199 0.108 0.055 0.026 -0.0015 0.0024 α _x 0.363 0.143 0.082 0.044 0.022 -0.0015 0.0026 α _y -0.506 -0.157 -0.081 -0.049 -0.035 -0.0276 0.0107

On the other hand, referring to Figure 4, the weighting matrix and the bias (biased value) includes a data set configuration step (S510) constituting a training data set consisting of an input value and an output value input to the ballistic simulation program Is obtained using the training data set.

The ballistic simulation program is a seven degree of freedom ballistic simulation program developed for ballistic analysis. In the present invention, the input value is selected as the velocity in the x, y, z-axis direction of the shell in the global coordinate system, the altitude and rotation speed of the shell.

The method for obtaining the weight matrix and the bias (biased value) may include an initial input value setting step of setting an initial weight matrix input value and an initial bias input value (S520);

Calculating a predicted impact point by applying the initial weight matrix input value and the initial bias input value to any one of the training data sets (S530);

An error determination step of calculating an impact error by comparing the predicted impact point with a target impact point, and comparing the calculated impact error with a preset error range (S540);

When the impact error is greater than the error range in the error determination step (S540), the weighting matrix input value and the bias input value are corrected according to the learning rate, and the input value correction step of transferring the modified input value to the result value calculation step (S570). );

A verification step (S550) of verifying with a learning data set when the impact error is smaller than the error range in the error determination step (S540);

When the impact error in the verifying step is smaller than the error range, the corresponding weighting matrix and the bias input value are determined as the final weighting matrix and the bias, and when the impact error in the verifying step is respectively larger than the error range, the initial weighting matrix input value. And a determining step (S560) of resetting the initial bias input value.

The error determining step (S540) is a difference value T between a predicted impact point K ₁ and a target impact point P ₁ calculated by applying the initial weight matrix input value and the initial bias input value to one of the training data sets. ₁ ) is compared with a preset error range α ₁ .

In the input value correcting step (S570), the learning rate refers to a difference between an input value of a weighting matrix set to an arbitrary initial value and an input value of a bias, that is, a difference between an initial input value from a corrected input value, and converges quickly if large. However, there is a disadvantage in that it converges at a large error value, and a small learning rate converges in a small error, but it takes a long time to converge. Therefore, the learning rate can be changed flexibly as learning progresses.

In addition, the verification step (S550) is to calculate the predicted impact point by applying the initial weight matrix input value and the initial bias input value to all input values of the training data set. In operation S560, the predicted impact point T _i calculated in the verification step S550 is compared with a preset error range α _i to determine a final weight matrix and a final bias, or input an initial weight matrix. Reset the value and initial bias input to repeat the process of determining the weight matrix and bias.

By using the final weighting matrix and the final bias determined as described above it is possible to calculate the path correction angle used in the present invention.

On the other hand, when comparing the simulation result graph according to the present invention and the simulation result graph by the proportional induction navigation as a comparative example of the present invention is as follows.

Figure 5 is a comparative example of the ballistic correction method of the shell according to the present invention, a graph showing a ballistic modified by the proportional navigation guidance technique.

6 is a comparative example of a method for modifying a trajectory of shells according to the present invention, which is a graph illustrating a commanded acceleration command modified by a proportional navigation guidance method.

Acceleration commands should not occur when the shell is flying along the reference flight path 402 which has no impact errors. However, the proportional navigation guidance method generates acceleration commands 406 and 408 from the point of induction to zero the change in the shell and target's line of sight, regardless of the impact error, so that the acceleration always occurs in the shell.

7 to 8 are graphs showing the impact of the impact point and the actual impact point predicted during flight of the shell through the weighting matrix and the bias in the method of ballistic correction of the shell according to the present invention, the weighting matrix and the bias obtained by the method of FIG. Shows the impact results predicted during the flight of the shell and the actual error of the impact points.

FIG. 7 shows the error range 502 and the deviation direction error 502 predicted during flight when the shell is fired at 35 degrees, and FIG. 8 is the range error predicted during flight when the shell is fired at 45 degrees ( 506 and error 508 in the bias direction are shown. The error has a maximum of 10m and an average of 3m, which is a very accurate result.

9 is a graph showing the flight path of the shell modified through the ballistic correction method of the shell according to the present invention, a flight path 602 having an impact error and a flight path modified using the method proposed in the present invention ( 604 is shown.

10 is a graph comparing the ballistic correction method of the shell according to the present invention with a proportional guided navigation method, and generates a small guided acceleration command (606, 608) when compared to the proportional navigation guided method, thereby fully reflecting the trajectory characteristics to the flight path You can see that it corrects.

FIG. 11 is a graph illustrating a change in impact point that is corrected through a ballistic correction method of the shell according to the present invention, and shows a change of the impact point as the flight path of the shell is modified by the method of the present invention. The ten triangles 612 represent the impact points of the shells with impact errors caused by various factors. When the flight path of the shells is modified by the proposed guidance method, the impact points change along the dotted line, and thus the desired target 610. Can hit the shells.

The ballistic correction method of the shell according to the present invention calculates the acceleration command using the path correction angle defined as the angle between the current speed and the speed toward the target instead of the change of the angle, thereby reducing the impact error of the shell having the parabolic flight trajectory. Minimize and improve the accuracy of shells.

The ballistic correction method of the shell according to the present invention does not generate a guided acceleration command for correcting a flight path when there is no impact error, and generates a small parabolic flight path of a shell by generating only a small guide command even when there is an impact error. It is advantageous in terms of saving kinetic energy.

The ballistic correction method of the shell according to the present invention requires only calculation by simple arithmetic operation and thus saves computation time, and does not require a high performance computer to handle many calculations.

The present invention is not limited to the above-described embodiments, and various changes can be made without departing from the gist of the present invention, which is understood to be included in the configuration of the present invention.

S100: flight data measurement step S200: path correction angle calculation step
S210: process of calculating the predicted impact point S220: process of calculating the impact error
S230: sensitivity matrix calculation process S240: path correction angle calculation process
S300: acceleration command calculation step S400: wing control step

Claims (7)

This is a method to modify the trajectory by adjusting the canard wing mounted on the shell with the controller.
A flight data measurement step of measuring flight data of the fired shell;
A path correction angle calculation step of calculating a path correction angle defined by an angle between a current speed derived from the measured flight data and a speed toward the target;
An acceleration command calculation step of calculating an induced acceleration command for controlling the canard wing with the calculated path correction angle; And
And a wing control step of controlling the canard wing by transmitting the calculated induced acceleration command to the controller. The method according to claim 1,
The flight data measurement step,
A position and speed sensing process of detecting a position coordinate of the X-axis and a Y-axis with respect to the firing point of the shell as a sensor in the shell and the velocity and direction of the shell at the corresponding position coordinate;
Determining whether the detected position is a target impact point; if the target impact point ends, the ballistic correction is terminated; if the target impact point does not include an impact point determination process of repeating the ballistic correction method. The method according to claim 1,
The flight data measuring step measures the velocity vector at the current position of the shell,
The acceleration command calculation step is expressed by equation

A method of correcting a trajectory of a shell, characterized in that for calculating an induced acceleration command.
Where N is the induction constant (designator designation), ΔA is the path correction angle (the first path correction angle (Δγ) in the X axis direction or the second path correction angle (ψ) in the Y axis direction, Δt is the predetermined vector change time,

: Current velocity vector of the measured shell The method according to claim 1,
The path correction angle calculation step,
A predicted impact point calculation process of calculating a position coordinate at which an impact of the shell is expected by using a weighting matrix and a bias stored in a memory mounted in the ballistic correction device;
An impact error calculation process of calculating an impact error between the predicted impact point and a target impact point;
A sensitivity matrix calculation process of obtaining a small change amount of an impact point using a weight change matrix and a small change amount of an impact point at a current shell position, and a sensitivity matrix using a small change amount of the path correction angle and a small change amount of an impact point;
And a path correction angle calculation process of calculating a path correction angle using the sensitivity matrix. The method of claim 4,
The process of calculating the sensitivity matrix calculates the sensitivity matrix using the small change amount of the path correction angle (εγ, εψ) and the small change amount of the impact point (εx, εy).

Method for modifying the trajectory of the shell, characterized in that for calculating the sensitivity matrix.
(Where, εγ, εψ: minute change of path correction angle, εx, εy: minute change of impact point,

,

,

,

: Sensitivity) The method according to claim 5,
The path correction angle calculation process includes a first path correction angle Δγ for correcting the impact error Δx in the cross direction and a second path correction angle ψ for correcting the impact error Δy in the biasing direction.

Ballistic correction method of the shell, characterized in that the calculation.
(Where, Δγ: first path correction angle, Δψ: second path correction angle, Δx: impact error in the cross direction, Δy: impact error in the bias direction,

,

,

,

: Sensitivity) The method of claim 4,
The path correction angle calculation step,
A data set construction step of constructing a training data set consisting of an input value inputted to a ballistic simulation program and an output value thereof;
An initial input value setting step of setting an initial weight matrix input value and an initial bias input value;
Calculating a predicted impact point by applying the initial weight matrix input value and the initial bias input value to any one of the training data sets;
An error determination step of calculating an impact error by comparing the predicted impact point with a target impact point, and comparing the calculated impact error with a preset error range;
An input value correction step of correcting a weighted matrix input value and a bias input value according to a learning rate when the impact error is greater than the error range in the error determination step, and transferring the corrected input value to the result value calculation step;
A verification step of verifying with a learning data set when the impact error is smaller than the error range in the error determining step;
When the impact error in the verifying step is smaller than the error range, the corresponding weighting matrix and the bias input value are determined as the final weighting matrix and the bias, and when the impact error in the verifying step is respectively larger than the error range, the initial weighting matrix input value. And using the obtained weighting matrix and bias, including the determining step of resetting the initial bias input value.

Images