RU2702458C1 - Firing method guided by a laser beam - Google Patents

Abstract

FIELD: military equipment.

SUBSTANCE: invention relates to missile guidance systems and can be used in antitank missile systems. According to the firing method, a missile controlled along a laser beam is used to measure the distance to the target and determine the speed of the target. Values of range and speed of target are entered into ground control system. Value of additional angular excess of the beam and total initial excess is calculated by addition of initial and additional excess. Time of beginning of reduction of total excess is calculated depending on distance to target and its speed. Controlled rocket is launched. Beam is deflected relative to TSL by total initial exceeding and deviation of beam in horizontal plane relative to TSL by value of additional angular excess in vertical plane. Beam is held in the specified position for a time corresponding to the calculated time of beginning of reduction of total excess. Flight of the missile is performed at the total initial excess until the beginning of the reduction of the total excess. Thereafter, alignment of beam axis with target sight line is performed. Additional excess value is taken as per analytical expression.

EFFECT: high probability of hitting target in auto tracking mode target and reduced probability of enemy detection of target irradiation by laser radiation.

1 cl, 2 dwg

Description

The invention relates to methods of firing guided missiles and can be used in guidance systems (SN) with teleorientation of a rocket in a laser beam.

The invention is intended to control an armament complex when hitting ground or low-speed air targets and can be used, for example, in anti-tank missile systems (ATGMs).

One of the problems solved in the development of strategic missiles guided missiles is to increase the accuracy of their guidance.

A known method of firing guided missiles with a deviation of the axis of the beam relative to the line of sight of the target (LCV) and their combination before approaching the target (Patent RU No. 2126946 from 11.25.1997, IPC F41G 7/26). The programmed change in the focal length in the optical system (sight) that implements this method ensures the constancy of the linear beam size and the magnitude of the excess at all flight ranges of the rocket, starting from the moment the change in focal length begins.

According to this method, shooting in excess mode can be carried out at a range of at least some value of D _min , which is determined by the time the rocket rises and descends from it. Before launching the rocket in the electronic circuit of the sight, the measured distance to the target D _{c is} compared with the stored range value Dmin, which allows the introduction of an excess. When D _i> D _min shooting is performed in a mode with the excess, and when D _n <D _min - without exceeding. In addition, in the electronic circuit of the sight, the start time of removing the excess is set in accordance with the measured range to the target D _c .

To ensure that the missile is fired in the indicated manner, two different launch angles between the missile axis and the axis of the beam at the moment of rocket launch for the two indicated firing modes must be implemented on the carrier.

The disadvantage of this method is the inability to provide two modes of fire in the case of a rigid design of the launch device.

Closest to the proposed is a method of firing a rocket, guided by a laser beam, described in patent RU No. 2516383 dated 11.29.2012 IPC F41G 7/26, and selected as a prototype. This method includes measuring the distance to the target and entering the measured value into the ground control system, setting the initial excess of the axis of the beam relative to the line of sight of the target, launching a guided missile, raising the axis of the beam to the initial excess of the line of sight of the target (LCV) after the moment of launch of the rocket, flight of the rocket at the initial excess until the time set in the ground control system in accordance with the measured range to the target, and the combination of the axis of the beam with the line of sight of the target.

The disadvantage of this method is that when shooting in a thermal imaging (TPV) channel (narrow and wide field of view) it does not provide automatic tracking of the target until the end of the flight, due to loss of the target’s image and long-term inertial tracking, which reduces the accuracy of shooting, especially when shooting at targets making a maneuver. The loss of the target image is due to the fact that the location of the nozzle in the mid-flight propulsion system, rotating at an angle of the guided missile in flight, increases the size of the spot sighting channel visible in the TPV during the operation of the mid-flight propulsion system. Moreover, the radius of the spot in the TPV channel from the rocket R _p can reach 1.5 ... 2.5 m

Shooting in this way provides a constant amount of excess, and by the end of the flight the distance between the missile spot and the target spot decreases in proportion to the flight range, which leads to their periodic association and loss of the target’s image by the end of the flight.

It is obvious that in order to avoid interruptions in auto tracking it is advisable to have an excess value Y _max , the linear size of which increases in proportion to the flight range, while ensuring a constant distance between the missile spot and the target spot in the strobe field of the automatic tracking vehicle (AS) and the subsequent alignment of the beam axis with the LCV.

The aforementioned can be realized, for example, by an additional shift of the center of the target AC gate of the target relative to the axis (crosshair) of the laser control channel (LCH) by the value Y _ac . corresponding to the deviation angle ε _ac .

The objective of the invention is to increase the likelihood of hitting the target in auto tracking mode and reduce the likelihood of the enemy detecting the fact of irradiating the target with laser radiation, which in turn reduces the likelihood of detecting the position of the complex.

This task is achieved by a method of firing a missile controlled by a laser beam, including measuring the distance to the target and entering the measured value into the ground control system, setting the initial excess of the axis of the beam relative to the line of sight of the target, launching the guided missile, raising the axis of the beam to the initial excess relative to the LCF after the moment missile launch, missile flight at an initial excess up to the point in time established in the ground control system in accordance with the measured range to the target, and combination si of the beam with the line of sight of the target, it’s new that, before launching the rocket, the speed of the target is determined, the value of the additional angular excess of the beam and the total initial excess is calculated by adding the initial and additional excess, the time of the start of the decrease in the total excess depending on the distance to the target and its speed, after the rocket is launched, they deflect the beam relative to the LCF by the total initial excess and keep it in the set position for the time corresponding to the calculated time the amount of the beginning of the decrease in the total excess, and from the moment the rocket starts to the moment the decrease in the total excess begins, the beam is deflected in the horizontal plane relative to the LC by the amount of the additional angular excess in the vertical plane.

In this case, the additional excess value is taken equal to the value

where ε _as - the additional value of the excess, deg .;

R _n is the radius of the observed spot from the propulsion system of the rocket, m;

D 'is the firing range with a total excess, m - is defined as the firing range, reduced by an amount determined by the average speed of the rocket and the time of lowering from exceeding the target line of sight.

The invention is illustrated by graphic material, where in FIG. 1 shows the flight path of a rocket in a vertical plane according to the prototype, and in FIG. 2 shows the flight path of the rocket in the vertical plane Y _p with the minimum possible deviation from the LC Y _min according to the proposed method, where it is indicated:

Y _max - the total initial excess of the axis of the beam relative to the line of sight of the target, m;

Y _np is the excess (position of the axis of the beam), m;

Y _in - the upper boundary of the beam, m;

Y _n - the lower boundary of the beam, m;

R _l is the radius of the laser beam, m;

- минимально возможное значение вертикального отклонения ракеты от линии визирования на этом участке полета, м;

- the minimum possible value of the vertical deviation of the rocket from the line of sight in this section of the flight, m;

Y _p - the trajectory of the rocket in the vertical plane;

t _c is the moment of beginning of beam narrowing, s;

Y _ac - the additional value of the excess AS, m

ε _as - the angular displacement of the center of the AC gate relative to the axis of the ZhU, deg.

Shooting a missile controlled by a laser beam according to the proposed method is as follows (Fig. 2).

After measuring the speed V _c and the distance to the target D _c , at time t _И and entering the measured value into the ground control system, the value of the minimum firing range D ' _min is entered into the sight, the time t _{3 is} determined in the electronic circuit of the sight similarly to the known method, and sets the initial excess Y ₀ taking into account the established range D ' _min .

In addition, a fixed angular displacement of the center of the axis of the beam of the laser control channel is set in the ground control system for guidance of the guidance drives by the value of ε _ac relative to the line of sight of the target, providing a total excess of the aiming crosshair -

In the ground-based control system, taking into account the range and speed of the target, the time t _{np of the} start of lowering the rocket with an excess of ε _ac is calculated in accordance with the formula:

где

Where

t _np — time of the beginning of lowering the rocket from exceeding ε _as , s;

D _q - distance to the target, m;

V _c - target speed, m / s;

V _p - average rocket speed, m / s,

t _p - the time of the shot, s;

t _op - the time required to lower the rocket when it exceeds the target line of sight, sec.

A guided missile is launched.

сохраняют неизменным. Время t₁ соответствует окончанию переходного процесса в системе наведения, которое с учетом возможных разбросов параметров системы наведения определяется как:During the time from the moment of the launch of the rocket t ₀ to the moment t _{1 the} total value

keep unchanged. Time t ₁ corresponds to the end of the transition process in the guidance system, which, taking into account possible variations in the parameters of the guidance system, is defined as:

For example, for a rocket with a low initial velocity, the cutoff frequency of the SN can be 0.25 Hz (0.25⋅2π rad / s); wherein t ₁ = 1.6 ... 2.2 s.

с момента времени t₁ до момента времени t₂ при максимально допустимой скорости подъема луча, которая устанавливается с учетом динамических свойств СН и конструктивных особенностей ее реализации в прицеле.The fulfillment of this condition ensures the guaranteed location of the rocket in the beam at the transient site (Fig. 2). After its completion, the excess is raised to the maximum excess

from time t ₁ to time t ₂ at the maximum permissible speed of the beam, which is set taking into account the dynamic properties of the SN and the design features of its implementation in the sight.

The further flight of the rocket occurs at an excess with an increase in the value proportional to the flight range up to the time t ₃ .

производят снятие превышения ЛКУ до превышения Y_ac аналогично известным способам.From time t ₃ to time t ₄ corresponding range

make removal of excess LKU to exceeding Y _ac similarly to known methods.

The further flight of the rocket occurs at an excess of Y _ac with an increase in proportion to the flight range, while ensuring a constant distance between the missile spot and the target spot and a stable auto tracking mode.

When the time t _{5 is} reached, using the guidance drives, the excess Y _{ac is} reduced until the center of the LKU coincides with the LCV. t _{op is} set taking into account the dynamic properties of SN and guidance drives.

The presence in the ground control equipment of an automatic tracking machine equipped with vertical and horizontal guidance drives allows you to apply this method more optimally. To do this, in the specified method, for the duration of the total excess in the vertical plane ε _ac relative to the line of sight of the target, an additional lateral offset of the guidance point is introduced using the guidance drives of the automated launcher by the same amount with the corresponding law of removing lateral deviation.

Ensuring the diagonal shift of the LKU targeting point relative to the line of sight of the target will eliminate the target’s irradiation and reduce the likelihood of the enemy detecting the target’s illumination at the stage of the missile’s aiming at the target in the SN, built on the basis of two mutually perpendicular injection lasers whose radiation areas are perpendicular to the axes of the measured coordinates, having a small instantaneous area and a short duration of exposure of the terrain in the target area.

The new operations indicated in the method are implemented using a control panel, a target tracking machine, a laser range finder, a tele-telescopic sight, a launcher with guidance drives.

The application of the proposed method of firing rockets controlled by a laser beam allows to increase the probability of hitting a target in the auto tracking mode of a target in a thermal imaging and television channel due to the exclusion of a transition to a long mode of inertia due to the close proximity of the target image and the rocket in the middle and final part of the flight.

In addition, this method will reduce the likelihood of detecting the position of the complex and the likelihood of jamming by reducing the likelihood of the enemy detecting the fact of irradiating the target with laser radiation by irradiating the target only at the time of the rocket's approach to the target.

Claims (5)

1. The method of firing a missile controlled by a laser beam, including measuring the distance to the target and entering the measured value into the ground control system, setting the initial excess of the axis of the beam relative to the line of sight of the target, launching a guided missile, raising the axis of the beam to the initial excess relative to the line of sight of the target - LCF after the moment of launching the rocket, the flight of the rocket at the initial excess until the time specified in the ground control system in accordance with the measured range to the target, and the alignment of the axis of the beam cha with the line of sight of the target, characterized in that before launching the rocket, determine the speed of the target, calculate the value of the additional angular excess of the beam and the total initial excess by adding the initial and additional excess, calculate the start time of the decrease in the total excess depending on the distance to the target and its speed, after the launch, the beam is deflected relative to the LCF by the total initial excess and held in position for a time corresponding to the calculated time the beginning of the decrease in the total excess, while from the moment the rocket launches to the moment the decrease in the total excess begins, the beam is deflected in the horizontal plane relative to the LC by the amount of the additional angular excess in the vertical plane. 2. The method of firing a rocket according to claim 1, characterized in that the additional excess is taken equal to the value

where R _n is the radius of the observed spot from the propulsion system of the rocket, m; D 'is the firing range with a total excess, m, defined as the firing range, reduced by an amount determined by the average speed of the rocket and the time of lowering from exceeding the target line of sight.

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