RU2388991C2 - Device for determining outer-ballistic parametres in invariant light target combined with ballistic track - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: device has a control frame, coaxial communication lines, a block of matching and threshold devices, an OR circuit, a computer, an information display device with a control panel for the tester, an emitter power supply, linear extended light sources and optical-electronic converters which form at least five light screens. The reference screen coincides with the target or is placed directly in front of the target, and two pairs of the other screens are arranged in pairs in parallel and are inclined at an acute angle to the reference screen. The first pair of screens is turned about a lateral axis and the second about a vertical axis. Light sources which form the reference screen and screens of the second pair are inclined towards the target, and light sources which form screens of the first pair are inclined towards the opposite side by angles of equal magnitude. The optical-electronic converters which form the reference screen and screens of the first pair are shifted towards the target, and optical-electronic converters which form screens of the second pair are shifted in the opposite direction by distance of equal modulus relative the initial position. The device can have a sixth screen fitted in parallel to the reference screen.

EFFECT: increased measurement accuracy for any shooting position and any speed of the bullet or shell.

2 cl, 5 dwg

Description

The invention relates to targets and ballistic traces for determining external ballistic parameters (initial speed, ballistic coefficient, speed at a given range and coordinates) of bullets and shells when firing direct fire and can be used for experimental determination of external ballistic parameters, as well as accuracy and accuracy of fire, bringing weapons to normal combat and for training and training.

A known method and device for implementing an invariant light target [Afanasyeva N.Yu. Information-measuring system based on light screens for testing small arms. PhD thesis. - Izhevsk: Izhevsk State. Tech. Un-t, 2003. - 127 p.].

равный отношению времени пролета между соответствующими экранами, зависит только от вертикальной координаты y_d и не зависит от скорости и от наклона траектории (соответственно от координат позиции y_p, z_p). Аналогично приборный коэффициент

зависит только от боковой координаты z_d и не зависит от скорости и от наклона траектории (соответственно от координат позиции y_p, z_d). Т.е. мишень инвариантна к скорости пули или снаряда и положению позиции. Так как экраны из-за погрешностей установки дополнительно повернуты на небольшие углы относительно других осей, зависимости приборных коэффициентов от координат имеют видThe closest analogue is the light target and the identification method implemented in it [Light target. RF patent No. 2213320 dated 09/27/2003 by application No. 2002116940, class. F41J 5/02 of June 24, 2002. VNIIGPE / Authors Afanasyeva N.Yu., Verkienko Yu.V., Kazakov V.S., Korobeinikov V.V. (prototype)]. The invariant target contains 5 screens, one of which 0 ₀ is counting and coincides or parallel to the registration plane (target), two of the other screens are pairwise parallel and inclined at acute angles relative to the readout, and the first pair of screens _{1 1} , _{2 2 is} rotated relative to the transverse (lateral) axis Z, and the second pair of screens E ₃ , E ₄ - relative to the vertical axis Y. Under the assumption that the speed is constant on a short blocked section of the path, the instrumental coefficient

equal to the ratio of the time of flight between the respective screens, it depends only on the vertical coordinate y _d and does not depend on the speed and on the inclination of the trajectory (respectively, on the coordinates of the position y _p , z _p ). Similar instrument ratio

depends only on the lateral coordinate z _d and does not depend on the speed and on the slope of the trajectory (respectively, on the coordinates of the position y _p , z _d ). Those. the target is invariant to the velocity of the bullet or projectile and position position. Since the screens, due to installation errors, are additionally rotated by small angles relative to other axes, the dependences of the instrument coefficients on the coordinates have the form

to determine the coefficients of models (1), (2), identification is carried out, during which for a series of shots the time of flight of a bullet or projectile through light screens and the coordinates of the points of entry into the registration plane (target) are simultaneously measured, and then, for example, by the least squares method the conditional equations of the form (1), (2) for all shots determine the coefficients a _i , b _i . After identification of the model (1), (2) is used in the mode of operation of the target to determine the coordinates of the points of impact.

The disadvantage of this method and device is the inability to determine external ballistic parameters (initial speed, ballistic coefficient and speed at a given range). In the case of a ballistic track, the coordinates of the position y _p , z _p and the coordinates of the point of impact y _d , z _d at a given distance are measured to determine external ballistic parameters.

In the absence of a reference sensor (BOT), the times are measured relative to the first screen and the reference time τ is unknown. In addition, because of the aftereffect of powder gases, it is undesirable to use DND. As a result, the total number of unknowns when solving the inverse problem of external ballistics is 8. This is the tangent of the casting angle γ ₀ , initial velocity ν ₀ , ballistic coefficient c, position coordinates y _p , z _p , coordinates of the point of impact y _d , z _d and the reference time τ. Thus, for an invariant target and a ballistic trace, a minimum of 8 screens must be installed.

The disadvantage of the existing method and device for its implementation is the large number of light screens and the need for their location along the entire length of the route, including on the site of inconstancy of the ballistic coefficient, where damping of nutation oscillations occurs. The installation of all light screens at the end of the route leads to large errors in the determination of external ballistic parameters due to inaccurate measurements of the intersection time of light screens. In addition, the distances between the light sources and the optoelectronic converters of the E ₃ , E ₄ screens are greater than the distances between the light sources and the optoelectronic converters of the remaining screens, which leads to signals of different sizes and an increase in the measurement error of the time the bullets or projectile cross the light screens.

The objective of the invention is to eliminate the disadvantages of the known device by combining an invariant target and a ballistic path containing 5 light screens located at the end of the path, and creating a device that allows, along with the coordinates of the point of impact to determine other external ballistic parameters in the area of the established angle of nutation (respectively, the established ballistic coefficient ) and reduce the number of unknowns to 6. You can also determine the coordinates of the point of impact y _d , z _{d by} directly measuring the coordinates of the holes in the paper target. The remaining unknowns are determined by the external ballistics equations recorded for at least two shots. In the case of two shots, the unknown are the 2 tangents of the throw angle, 2 initial velocities, 2 times of the origin, 2 position coordinates and a ballistic coefficient, which is the same for the same bullets or shells in a steady section. Thus, in the case of at least two shots, the number of unknowns is less than the number of equations, which ensures the determination of external ballistic parameters with a minimum number of screens equal to five, at their location at the end of the ballistic path, where the mutation damped. In addition, the aftereffect of powder gases is additionally excluded when a bullet or projectile leaves the bore. When installing an additional screen parallel to the reference one, for each shot, all parameters and individual ballistic coefficients of each bullet or projectile are determined by the equations of external ballistics.

To ensure the same distances between the light sources and the optoelectronic converters, the E ₀ , E ₁ , E ₂ screens are rotated counterclockwise relative to the vertical axis, and the E ₃ , E ₄ screens are turned at the same absolute angle, but in the opposite direction.

EFFECT: proposed device of a combined invariant light target and a ballistic path provides the same operating conditions for all optoelectronic converters and determination of external ballistic parameters with a minimum number of screens, regardless of position and speed when all screens are located on a section of an established ballistic coefficient.

Figure 1 shows a diagram of a light target; figure 2 - arrangement of optoelectronic converters and light sources in the dash; figure 3 - setting the position of the screen by the equation in the traces; figure 4 - determination of the point of intersection of the trajectory with the screen; figure 5 - decomposition of the movement into portable and relative under the influence of gravity (LB - throw line; y _sp - sagging trajectory under the action of acceleration of gravity).

The device contains light sources AND ₁ , ..., AND ₄ , optoelectronic converters D ₀ , ..., D ₄ , control frame KR, coaxial communication lines 1, block matching and threshold devices 2, OR 3, calculator 4, information display device with tester panel 5; power supply unit for emitters 6. Test weapons are installed on the machine 7 or held by the tester.

The outputs of the amplifiers of the photocurrent of optoelectronic converters by coaxial communication lines 1 are connected to the inputs of the block of matching and threshold devices 2, the outputs of which are connected to the inputs of the OR 3 circuit, the output of the OR circuit is connected to a computer 4 connected to the information display device and the tester panel 5.

Light sources are installed, for example, in a vertical plane (on the shooting gallery wall), two of them And ₃ , And _{4 are} installed in parallel with an inclination at an angle α = 10-15 ° towards the target, and two light sources And ₁ , And _{2 are} tilted relative to the first two in the opposite direction, forming an angle 2α with them. Optoelectronic converters D ₀ , D ₁ , D _{2 are} mounted on the side opposite to the sheaf of trajectories (shooting gallery wall) with the same offset relative to the light sources in the direction of the target (control frame) installed for identification after the light source And ₄ . Optoelectronic converters D ₃ , D ₄ are shifted towards the position by the same absolute value as the others. Optoelectronic converters are oriented to light sources and tilted so that their slit diaphragms are parallel to the corresponding light sources. In this case, the source of light and ₄ two optoelectronic converters D ₀ oriented, D _4. This arrangement provides the minimum width of the light screens, the parallelism of the screens E ₁ , E ₂ and the screens E ₃ , E ₄ , the slope of the screens E ₁ , E ₂ relative to the reference screen E ₀ with rotation relative to the side axis and the screens E ₃ , E ₄ - with rotation about a vertical axis. The parallelism of the pairs of screens and their inclination relative to the reference one with rotation relative to the vertical and lateral axes provide a target with models (1), (2), which is invariant to the position of the position of the bullet or projectile, under the same operating conditions of all optoelectronic converters.

The mathematical essence of the method of the invention is as follows.

When fired at the moments when the bullet or projectile crosses the light screens, the times t ₁ , ..., t ₄ , t ₀ are fixed in the timer of the calculator. In the absence of a reference sensor, the screen crossing time _{i i} is equal to t _i + τ, i.e. measured to an unknown count τ.

To solve the inverse problem of external ballistics, use the system of equations for argument x (range) [Konovalov AA, Nikolaev Yu.V. External ballistics. - Izhevsk: Publ. IPM UB RAS, 2003. - 191 p.]

and by argument t (time)

- проекция скорости на ось Х; γ=tgϑ - тангенс угла наклона вектора скорости; G(ν)- функция сопротивления по закону 1943 года; c(x) - баллистический коэффициент пули или снаряда, зависящий от дальности стрельбы; Н(y)=П(y)/П₀ - отношение плотности воздуха на высоте y к плотности воздуха при нормальной атмосфере (в нашем случае Н(y)=1).Here

- projection of speed on the X axis; γ = tgϑ is the slope of the velocity vector; G (ν) is the resistance function according to the law of 1943; c (x) is the ballistic coefficient of a bullet or projectile, depending on the firing range; H (y) = P (y) / P ₀ is the ratio of the density of air at a height y to the density of air in a normal atmosphere (in our case, H (y) = 1).

We denote the solution of ballistic equations by the argument x:

and by argument t:

The position of the screen in the coordinate system XYZ set the equation in the traces (figure 3)

where a = tgα, b = -tgβ; positive directions for reading angles α and β are selected in the right coordinate system when turning from X to Y and from Z to X counterclockwise.

XY plane screen equation

In the shooting plane X * Y * equation of the screen

Where

(фиг.4) можно определить из совместного решения уравнения экрана (14) и уравнения траекторииAbscissas (ranges)

(Fig. 4) can be determined from a joint solution of the screen equation (14) and the trajectory equation

If the external ballistic parameters γ ₀ , ν ₀ , c (x) are unknown, then to fix the trajectory and determine the points of intersection of the trajectory with the screens, we use the decomposition of the motion into a portable motion along the cast line and relative vertical downward by gravity, as shown in Fig. 5. We have

where y _sp - sagging due to free fall; g = 9.8065 m / s ² - acceleration of gravity.

The system operates as follows.

In the identification mode, immediately behind the reading light screen E ₄ , a control frame of the CR is installed with graph paper glued to it. After the shot, the bullet sequentially crosses the light screens. When the light screen crosses, a part of the light flux incident from the linear extended light source onto the photodetector of the optoelectronic converter is shaded, and an electric pulse is generated at the output of the photocurrent amplifier, which is transmitted through the coaxial communication line 1 to the input of the matching unit and threshold devices 2, from it the output goes to the OR 3 circuit. From the output of the OR 3 circuit, electrical signals corresponding to all the light screens are sequentially fed to the interrupt bus of the computer 4. The interrupt signals the state of the computer timer, and time codes are recorded in its memory. After a series of shots are fired at the given points of the control frame or after each of them, the coordinates of the holes are measured (and marked to avoid confusion). After a given number of shots, for example, the least squares method is used to identify models (1), (2). In this case, each time the sum of the squared deviations and deviations for each shot is calculated. Shots with large deviations are rejected and fired or shot, or defective points simply exclude and repeat the determination of model coefficients. If in the operating mode the coordinates of the points of impact are determined using a light target, then the control frame is removed.

In the operating mode (operating mode), the equipment operates similarly to the identification mode. After at least two shots and recording in the computer memory the moments of time the bullet or projectile crossed the light screens from the system of equations (1), (2), the coordinates of the point of impact are determined. After that, write down the system of equations of external ballistics for the time of crossing at least two bullets of all light screens with known coordinates of the hit points and unknown initial speeds, throwing angles, timing for each shot and the same position coordinates and ballistic coefficient for all shots, and finally , unknown external ballistic parameters are determined from the solution of this system. If there is an additional screen parallel to the reference screen, for each shot, all parameters and the individual ballistic coefficient of each bullet or projectile are determined by the equations of external ballistics.

The proposed device of the combined invariant light target and ballistic track provides the determination of external ballistic parameters for any position of the position and any velocity of the bullet or projectile by measuring the coordinates of the invariant target or holes in the millimeter target, as well as improving the accuracy of measurements due to the identical operating conditions of the optoelectronic transducers of all screens .

Claims (2)

1. A device for determining external ballistic parameters in an invariant light target combined with a ballistic path, containing a control frame, coaxial communication lines, a block of matching and threshold devices, an OR circuit, a computer, an information display device with a tester panel, an emitter power supply unit, linear extended light sources and optoelectronic converters forming at least five light screens, the support screen of which coincides with the target or is installed immediately before while two pairs of other screens are paired and tilted at an acute angle to the support screen, while the first pair of screens is rotated relative to the side axis, and the second is relative to the vertical axis, characterized in that the light sources forming the support screen and screens of the second pair, are tilted towards the target, and the light sources forming the screens of the first pair are in the opposite direction at the same angles in absolute value, while the optoelectronic converters forming the supporting screen and the screens of the first pair are shifted to the side it targets, and the optoelectronic converters forming the screens of the second pair - in the opposite direction at the same distance in absolute value relative to the starting position. 2. The device according to claim 1, characterized in that it is equipped with a sixth screen mounted parallel to the support screen.

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