CN117663914B - Guidance method for 360-degree omnibearing attack target - Google Patents

Abstract

The invention discloses a guidance method for a 360-degree omnibearing attack target, which integrates the flying speed, the residual flying time, the line-of-sight angular speed and the angle information of a missile, forms a high-low and horizontal two-direction proportional guidance overload instruction according to an optimal proportional guidance rule according to an expected ballistic inclination angle and a ballistic deflection angle, and controls the missile to strike the target at an expected angle. The invention can realize that the target is attacked at any angle at the tail end on the premise of ensuring the hit precision of the missile.

Description

A 360° all-round attack target guidance method

Technical Field

The invention belongs to the technical field of missiles, and in particular relates to a guidance method for attacking a target in all directions at 360 degrees.

Background Art

In the existing technology, missiles can use combined navigation + infrared/television composite guidance, and attack targets include hangars, bunkers, etc. In order to achieve efficient damage to the target, it is necessary to attack its weak parts. The opening direction of the hangar and bunker is uncertain relative to the incoming direction of the missile, which puts high requirements on the angle direction of the missile hitting the target. It is urgent to achieve a 360° all-round strike on the target.

Summary of the invention

In order to overcome the shortcomings of the prior art, the present invention provides a 360° all-round attack target guidance method, which integrates the missile flight speed, remaining flight time, line of sight angular velocity and angle information, and forms high and low and horizontal proportional guidance overload instructions according to the expected trajectory inclination and trajectory deviation according to the optimal proportional guidance law, and controls the missile to strike the target at the expected angle. The present invention can achieve the attack on the target at any angle at the end under the premise of ensuring the missile's hit accuracy.

The technical solution adopted by the present invention to solve the technical problem includes the following steps:

Step 1: Define the launch coordinate system, target local coordinate system and line of sight coordinate system, which are defined as follows:

Launch coordinate system _{OF-xFyFzF : The} origin of the coordinate is at the launch point, the x-axis is in the horizontal plane of the launch point, pointing _to the target is positive, the y-axis is along the vertical line of the launch point, upward is positive, and the z-axis, x-axis and y-axis form a right-handed coordinate system;

Target local coordinate system O _t -x _t y _t z _t : The origin of the coordinate is at the target shooting point, the x-axis is in the horizontal plane of the target point, and the positive direction is opposite to the direction pointing to the shooting point, the y-axis is along the vertical line of the target point, and the positive direction is upward, and the z-axis, the x-axis and the y-axis form a right-handed coordinate system;

Line of sight coordinate system O _s -x _s y _s z _s : The origin of the coordinate is the center of mass of the missile, the x-axis points to the target, the y-axis is in the plumb plane containing the x-axis and is perpendicular to the x-axis, with the upward direction being positive, and the z-axis, the x-axis and the y-axis form a right-handed coordinate system;

Step 2: The overload command formula in the line of sight coordinate system is as follows:

High and low direction overload instructions:

Horizontal overload command:

In the formula,

- Vertical and horizontal line of sight angular velocity;

q _α , q _β - vertical and horizontal sight angles;

K _α , K _β - proportional guidance coefficients in vertical and horizontal directions;

t _go – remaining flight time;

θ _DF , θ _DP - expected trajectory inclination angle and expected trajectory deviation angle when the missile hits the target;

V – missile flight speed;

g – acceleration due to gravity;

Step 3: Determine the missile attack direction φ ₀ and the fall angle θ ₀ relative to the local horizontal plane of the target;

The missile attack direction and landing angle are established relative to the target's local coordinate system O _t -x _t y _t z _t . O _t -x _t y _t z _t is obtained by rotating the launch coordinate system O _F -x _F y _F z _F around the O _F z _F axis by an angle Δ. The tangent value of Δ is obtained by dividing the missile-target distance by the earth's radius r.

_The missile attack direction is the angle between the projection of the missile's velocity direction on the target's local coordinate system _{xtOtzt plane} at the moment of hitting the target and the target's local coordinate system _{Otxt axis} . The velocity direction projection on the left side of the _{Otxt axis} is positive, and on the right side is negative. The fall angle refers to the angle between the missile _'s velocity at the moment of hitting the target and the target's local coordinate system _{xtOtzt plane} . The attack direction and fall angle are determined by the target opening orientation and the warhead performance indicators.

The calculation formula of Δ is as follows:

Among them, x _t and y _t are the coordinate positions of the target in the launch coordinate system;

Step 4: Convert the missile attack direction φ ₀ and the fall angle θ ₀ relative to the local horizontal plane of the target to the launch coordinate system;

The velocity direction of the launch coordinate system is described by the ballistic inclination angle θ and the ballistic deviation angle ψ _v. θ refers to the angle between the projection of the velocity direction on the launch coordinate system x _F O _F z _F plane and the ox axis, and ψ _v refers to the angle between the velocity direction and the launch coordinate system x _F O _F y _F plane.

The definition method of θ and ψ _v is called the 3-2-1 rotation sequence, and the definition method of θ ₀ and φ ₀ is called the 2-3-1 rotation sequence. When controlling the missile flight, firstly calculate the angle values θ _t and φ _t corresponding to the expected velocity direction of the missile at the time of hitting the target according to the 3-2-1 rotation sequence based on θ ₀ and φ ₀ , and then transfer them to the launch coordinate system to obtain the expected trajectory inclination angle θ _DF and the expected trajectory deviation angle θ _DP . The specific formula is as follows:

Target local coordinate system expected trajectory inclination, 3-2-1 rotation sequence:

Target local coordinate system expected trajectory deviation angle, 3-2-1 rotation sequence: φ _t = arcsin (cosθ ₀ sinφ ₀ );

Expected trajectory inclination in the launch coordinate system: θ _DF =θ _t +Δ;

Expected trajectory deviation angle in the launch coordinate system: θ _DP = φ _t ;

Step 5: Calculate the line of sight angular velocity and line of sight angle in the line of sight coordinate system. The calculation formula is as follows:

High and low sight angle:

Angular velocity of sight in high and low directions:

Horizontal sight angle:

Horizontal line of sight angular velocity: Among them, _xm , _ym , _zm are the position coordinates of the missile in the launch coordinate system, _xt , _yt , _zt are the position coordinates of the target in the launch coordinate system, is the distance between the projectile and the target, is the rate of change of missile-target distance; V _x , V _y , V _z represent the three-axis speed of the missile in the launch coordinate system;

Step 6: Calculate the remaining flight time using the following formula:

time left:

Step 7: Generate the proportional guidance overload command for all-round attack in the line of sight coordinate system. The calculation formula is as follows:

High and low direction overload instructions:

Horizontal overload command:

The trajectory simulation is verified using the omnidirectional attack proportional guidance overload command, and the miss distance and angle control accuracy are improved by adjusting the proportional guidance coefficient.

Preferably, K _α =4 and K _β =4.

The beneficial effects of the present invention are as follows:

The invention has strong versatility, a simple design process, is easy to implement, is suitable for striking targets such as hangars and bunkers with attack angle requirements, and has broad application prospects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of the method of the present invention.

FIG. 2 is a ballistic curve of attacking a target at different angles according to an embodiment of the present invention.

FIG. 3 is a curve of the distance between the projectile and the target when attacking the target at different angles according to an embodiment of the present invention.

FIG. 4 is a graph showing trajectory inclination curves of attacking a target at different angles according to an embodiment of the present invention.

FIG. 5 is a curve of trajectory deflection when attacking a target at different angles according to an embodiment of the present invention.

FIG. 6 is a curve of the height of the sight line angle when attacking the target at different angles according to an embodiment of the present invention.

FIG. 7 is a graph showing horizontal sight angles of attacking a target at different angles according to an embodiment of the present invention.

FIG8 is a block diagram showing the principle of the guidance method of the present invention.

DETAILED DESCRIPTION

The present invention is further described below in conjunction with the accompanying drawings and embodiments.

The technical problem to be solved by the present invention is to provide a simple and practical method for controlling the angle of impact, so as to solve the problem of medium- and short-range conventional missiles attacking targets in all directions. The principle block diagram is shown in FIG8 .

The reference coordinate systems involved include the launch coordinate system, the target local coordinate system and the line of sight coordinate system, which are defined as follows:

Launch coordinate system _{OF-xFyFzF : The} origin of the coordinate is at the launch point, the x-axis is in the horizontal plane of the launch point, pointing _to the target is positive, the y-axis is along the vertical line of the launch point, upward is positive, and the z-axis, x-axis and y-axis form a right-handed coordinate system;

Target local coordinate system O _t -x _t y _t z _t : The origin of the coordinate is at the target shooting point, the x-axis is in the horizontal plane of the target point, and the positive direction is opposite to the direction pointing to the shooting point, the y-axis is along the vertical line of the target point, and the positive direction is upward, and the z-axis, the x-axis and the y-axis form a right-handed coordinate system;

Line of sight coordinate system O _s -x _s y _s z _s : The origin of the coordinate is the center of mass of the missile, the x-axis points to the target, the y-axis is in the plumb plane containing the x-axis and is perpendicular to the x-axis, with the upward direction being positive, and the z-axis, the x-axis and the y-axis form a right-handed coordinate system;

The overload command formula of this guidance method in the line of sight coordinate system is as follows:

High and low direction overload instructions:

Horizontal overload command:

In the formula,

- Angular velocity of sight line in vertical and horizontal directions;

q _α , q _β - vertical and horizontal sight angles;

K _α , K _β - proportional guidance coefficients in vertical and horizontal directions;

t _go – remaining flight time;

θ _DF , θ _DP - expected trajectory inclination angle and expected trajectory deviation angle when the missile hits the target;

V – missile flight speed;

g – acceleration due to gravity;

The specific implementation process of the guidance method is shown in Figure 1.

The guidance method can be divided into six steps:

Step 1: Determine the missile attack direction φ ₀ and the angle of fall θ ₀ relative to the local horizontal plane of the target. The missile's attack direction and angle of fall indicators are established relative to the target's local coordinate system O _t -x _t y _t z _t . O _t -x _t y _t z _t is obtained by rotating the launch coordinate system O _F -x _F y _F z _F around the O _F z _F axis by an angle Δ. The tangent value of Δ is obtained by dividing the missile-target distance by the radius of the earth r. The missile's attack direction refers to the angle between the projection of the missile's velocity direction in the target's local coordinate system x _t O _t z _t plane at the time of hitting the target and the target's local coordinate system O _t x _t axis. The velocity direction projection on the left side of the O _t x _t axis is positive, and on the right side is negative; the angle of fall refers to the angle between the missile's velocity at the time of hitting the target and the target's local coordinate system x _t O _t z _t plane. The attack direction and angle of fall are determined by the target opening orientation and the warhead performance indicators.

The calculation formula of Δ is as follows:

x _t and y _t are the coordinate positions of the target in the launch coordinate system.

Step 2: Convert the missile's terminal attack direction φ ₀ and the angle of fall θ ₀ relative to the target's local horizontal plane to the launch coordinate system. When the missile is controlled in the launch coordinate system, the method for defining the velocity direction is different from φ ₀ and θ ₀ , and needs to be unified. The velocity direction in the launch coordinate system is described by the trajectory inclination angle θ and the trajectory deviation angle ψ _v. θ refers to the angle between the projection of the velocity direction on the launch coordinate system x _F O _F z _F plane and the ox axis, and ψ _v refers to the angle between the velocity direction and the launch coordinate system x _F O _F y _F plane. The definition method of θ and ψ _v is called the 3-2-1 rotation sequence, and the definition method of θ ₀ and φ ₀ is called the 2-3-1 rotation sequence. When the missile is controlled in flight, first calculate the angle values θ _t and φ _t corresponding to the 3-2-1 rotation sequence of the expected velocity direction at the time of missile hitting the target based on θ ₀ and φ ₀ , and then convert it to the launch coordinate system to obtain the expected trajectory inclination angle θ _DF and the expected trajectory deviation angle θ _DP . The specific formula is as follows:

Target local coordinate system expected trajectory inclination (3-2-1 rotation sequence):

Expected trajectory deviation angle in the target local coordinate system (3-2-1 rotation sequence): φ _t = arcsin (cosθ ₀ sinφ ₀ )

Expected trajectory inclination in the launch coordinate system: θ _DF = θ _t + Δ

Expected trajectory deviation angle in the launch coordinate system: θ _DP = φ _t

Step 3: Calculate the line of sight angular velocity and line of sight angle. The calculation formula is as follows:

High and low sight angle:

Angular velocity of sight in high and low directions:

Horizontal sight angle:

Horizontal line of sight angular velocity:

Among them, _xm , _ym , _zm are the position coordinates of the missile in the launch system, _xt , _yt , _zt are the position coordinates of the target in the launch system, is the distance between the projectile and the target, is the rate of change of the projectile-target distance.

Step 4: Calculate the remaining flight time. The calculation formula is as follows:

time left:

Step 5: Generate the proportional guidance overload command for all-round attack in the line of sight coordinate system. The calculation formula is as follows:

High and low direction overload instructions:

Horizontal overload command:

By using the omnidirectional attack proportional guidance overload command to conduct trajectory simulation verification, the miss distance and angle control accuracy can be improved by adjusting the proportional guidance coefficient.

Example:

Step 1: Determine the position of the target in the launch system. The launch coordinate system OF _{- xFyFzF} is rotated around _OFzF by _an angle _Δ to _coincide with the target local coordinate system _{Ot - xtytzt} . Calculate Δ _based on the position information.

Among them, _xt is the coordinate of the target in the launch system, _yt is the coordinate of the target in the launch system, and r is the radius of the earth.

Step 2: Determine the missile terminal attack direction φ ₀ and the fall angle θ ₀ relative to the local horizontal plane of the target in the 2-3-1 rotation sequence according to actual needs, and calculate the expected trajectory inclination angle θ _t and the expected trajectory deviation angle φ _t in the local coordinate system of the target in the 3-2-1 rotation sequence;

φ _t = arcsin(cosθ ₀ sinφ ₀ )

Combined with Δ, calculate the expected trajectory inclination angle θ _DF and the expected trajectory deviation angle θ _DP under the launch system

θ _DF =θ _t + Δ

θ _DP = φ _t

In the simulation of this embodiment, the following 9 groups of expected trajectory inclination angles θ _DF and expected trajectory deviation angles θ _DP under the launch system are selected to verify that the algorithm can achieve an all-round attack on the target:

Step 3: Calculate the line of sight angular velocity using the relative position relationship between the missile and the target and and the sight angles q _α and q _β ;

in, is the distance between the projectile and the target, is the rate of change of the projectile-target distance.

Step 4: Use the projectile-target distance R and the projectile-target distance change rate Calculate the remaining flight time t _go ;

Step 5: In this embodiment, the proportional guidance coefficients K _α = 4 and K _β = 4 are selected. The remaining time correction term is introduced into the optimal proportional guidance law, and the proportional guidance overload instructions in the vertical and horizontal directions in the line of sight coordinate system are designed;

Figures 2 to 7 are examples of using the omnidirectional attack proportional guidance method, showing the missile's strikes on the target in nine extreme directions. Figures 2 to 3 show the trajectory shape and the relative distance curves of the missile and the target at different attack angles. The missile can finally hit the target accurately at different attack angles; Figures 4 to 7 respectively show the curves of the trajectory inclination, trajectory deviation, high and low sight angles, and horizontal sight angles. Under simulation conditions, the high and low sight angles and the trajectory inclination at the end of the missile trajectory tend to be consistent, the horizontal sight angle and the trajectory deviation angle tend to be consistent, and the error between the actual landing angle and the expected landing angle is no more than 0.1°, meeting the requirements for precise landing angle control.

The simulation results show that the omnidirectional attack proportional guidance method not only ensures the guidance accuracy of the missile weapon system, but also ensures that the missile can strike the target in all directions at any desired angle of attack.

Claims (2)

1. The guidance method for the 360-degree omnibearing attack target is characterized by comprising the following steps of;

step 1: defining an emission coordinate system, a target local coordinate system and a sight line coordinate system, the definition is as follows:

Emission coordinate system O _F-x_Fy_Fz_F: the origin of coordinates is located at the transmitting point, the x-axis is located in the horizontal plane of the transmitting point, the pointing target is positive, the y-axis is positive upwards along the direction of the plumb line of the transmitting point, and the z-axis, the x-axis and the y-axis form a right-hand coordinate system;

Target local coordinate system O _t-x_ty_tz_t: the origin of coordinates is at the target shooting point, the x-axis is in the horizontal plane of the target point, the direction opposite to the direction of the shooting point is positive, the y-axis is positive upwards along the direction of the plumb line of the target point, and the z-axis, the x-axis and the y-axis form a right-hand coordinate system;

Line of sight coordinate system O _s-x_sy_sz_s: the origin of coordinates is the mass center of the missile, the x axis points to the target, the y axis is in a plumb plane containing the x axis and is vertical to the x axis, the upward direction is positive, and the z, the x axis and the y axis form a right-hand coordinate system;

step 2: the overload instruction formula under the line-of-sight coordinate system is as follows:

High-low direction overload instruction:

horizontal overload instruction:

In the method, in the process of the invention,

-A high-low, horizontal line-of-sight angular velocity;

q _α、q_β -height, horizontal direction line of sight angle;

K _α、K_β -high-low and horizontal proportional guide coefficients;

t _go -remaining time of flight;

θ _DF、θ_DP —desired ballistic dip angle, desired ballistic deflection angle at the moment of target hit by the missile;

v-missile flight speed;

g-gravitational acceleration;

Step 3: determining a missile attack direction phi ₀ and a falling angle theta ₀ relative to a target local horizontal plane;

The missile attack direction and the falling angle are established relative to a target local coordinate system O _t-x_ty_tz_t, O _t-x_ty_tz_t is obtained by rotating a transmitting coordinate system O _F-x_Fy_Fz_F around an O _Fz_F shaft by an angle delta, and the tangent value of delta is obtained by dividing the missile distance by the earth radius r;

The missile attack direction is an included angle between the projection of the speed direction of the missile at the moment of hitting the target in the plane of the target local coordinate system x _tO_tz_t and the O _tx_t axis of the target local coordinate system, wherein the projection of the speed direction on the left side of the O _tx_t axis is positive, and the projection of the speed direction on the right side is negative; the falling angle is an included angle between the speed of the shot at the moment of hit of the target and the plane of the target local coordinate system x _tO_tz_t; the attack direction and the falling angle are determined by the target opening direction and the warhead performance index;

The calculation formula of delta is as follows:

wherein x _t and y _t are coordinate positions of the target in the emission coordinate system;

Step 4: converting the missile attack direction phi ₀ and the falling angle theta ₀ relative to the target local horizontal plane into a launching coordinate system;

The velocity direction of the emission coordinate system is described by a ballistic inclination angle theta and a ballistic deflection angle phi _v, wherein theta refers to an included angle between the projection of the velocity direction on the plane of the emission coordinate system x _FO_Fz_F and the ox axis, and phi _v refers to an included angle between the velocity direction and the plane of the emission coordinate system x _FO_Fy_F;

The definition method of θ and ψ _v is referred to as 3-2-1 rotation order, and the definition method of θ ₀ and φ ₀ is referred to as 2-3-1 rotation order; during missile flight control, firstly, according to theta ₀ and phi ₀, angle values theta _t and phi _t corresponding to the expected speed direction at the moment of missile hit according to the rotation sequence of 3-2-1 are calculated, and then the angle values are transferred to a launching coordinate system to obtain an expected ballistic inclination angle theta _DF and an expected ballistic deflection angle theta _DP, wherein the specific formula is as follows:

Target local coordinate system desired ballistic tilt angle, 3-2-1 rotation order:

Target local coordinate system desired ballistic deflection, 3-2-1 rotation order: phi _t＝arcsin(cosθ₀sinφ₀);

the desired ballistic tilt angle in the emission coordinate system: θ _DF＝θ_t ++Δ;

The desired ballistic deflection angle in the emission coordinate system: θ _DP＝φ_t;

Step 5: the line of sight angular velocity and the line of sight angle of the line of sight coordinate system are calculated as follows:

Viewing angle in high-low direction:

High-low direction line-of-sight angular velocity:

Horizontal viewing angle:

horizontal line of sight angular velocity:

Wherein x _m、y_m、z_m is the position coordinate of the missile in the emission coordinate system, x _t、y_t、z_t is the position coordinate of the target in the emission coordinate system, For the distance between the bullet and the eye,Is the bullet-eye distance change rate; v _x、V_y、V_z denotes the tri-axial velocity of the missile in the launch coordinate system;

step 6: the remaining time of flight is calculated as follows:

Remaining time:

Step 7: and carrying out ballistic simulation verification by utilizing an omnibearing attack proportional guide overload instruction, and improving the off-target quantity and the angle control precision by adjusting a proportional guide coefficient.

2. The method of claim 1, wherein K _α =4 and K _β =4 are used for the guidance of a 360 ° omnidirectional attack target.