EP0802390A1 - Method for disintegrating time setting particularly for a programmable projectile - Google Patents

Abstract

The disaggregation time determination involves performing a calculation based upon an impact distance (RT) to a target determined from sensor data, a projectile velocity (Vm) measured at a muzzle of a gun barrel and a given disaggregation distance (Dz). The disaggregation distance is kept constant by correction of a disaggregation time (Tz). The correction is performed using the equation: Tz(Vm) = Tz + K*(Vm-Vov) Vov is a lead velocity of the projectile. K is a correction factor. The disaggregation distance is a distance between an impact point and a disaggregation point of the projectile.

Description

The invention relates to a method for calculating the disassembly time, in particular of a programmable projectile, the calculation being based on at least one target distance to a target object determined from sensor data, a projectile speed measured at the muzzle of a gun barrel and a predetermined optimal disassembly distance between a meeting point and a disassembly point of the projectile is.

With the European patent application 0 300 255 a device has become known which has a measuring device for the projectile velocity arranged at the mouth of a gun barrel. The measuring device consists of two ring coils arranged at a certain distance from one another. When a bullet passes through the two ring coils, a pulse is generated in short succession in each ring coil due to the change in magnetic flux that occurs. The pulses are fed to an electronic evaluation system, in which the temporal distance of the impulses and the distance between the ring coils the bullet speed is calculated. In the direction of movement of the projectile, a transmitting coil is arranged behind the measuring device for the speed, which co-operates with a receiving coil provided in the projectile. The receiving coil is connected to a counter via a high-pass filter, which is connected on the output side to a timer. A disassembly time is formed from the calculated bullet speed and a hit distance to a target object determined from sensor data, which is inductively transmitted to the bullet immediately after the measuring device has flown through. With this disassembly time, the time fuse is set so that the projectile can be disassembled in the area of the target object.

If projectiles with sub-projectiles are used (ammunition with primary and secondary ballistics), an attacking target can be destroyed by multiple hits, as is known, for example, from a publication OC 2052 d 94 from the company Oerlikon-Contraves, Zurich, if, after the sub-projectiles have been ejected, Time of disassembly the expected area of the target is occupied by a cloud formed by the subprojectiles. When dismantling such a projectile, the part carrying the subprojectiles is separated and torn open at predetermined breaking points. The ejected sub-projectiles describe a swirl-stabilized trajectory caused by the rotation of the projectile and lie evenly distributed on approximately semicircular curves of circular areas of a cone, so that a good chance of hitting or firing can be achieved.

In the device described above, scattering in the disassembly distance, which is caused, for example, by scattering in the bullet speed and / or the use of non-updated values, cannot always achieve a good probability of being hit or fired. With larger disassembly distances, the circular area would be larger, but the density of the subprojectiles would be smaller. The reverse occurs with smaller disassembly distances: the density of the subprojectiles would be greater, but the circular area would be smaller.

The invention has for its object to propose a method and a device according to the preamble, by means of which an optimal hit or shot probability can be achieved while avoiding the disadvantages mentioned above.

This object is achieved by the invention specified in claim 1 . Here, a given optimal disassembly distance between a disassembly point of the projectile and a meeting point of the target is kept constant by correcting the disassembly time of the projectile. The correction is made by adding a correction factor multiplied by a speed difference to the disassembly time. The speed difference is formed from the difference between the current measured floor speed and a lead speed of the projectile, the lead speed being calculated from the mean of a number of previous successive floor speeds.

The advantages achieved with the invention can be seen in the fact that a given disassembly distance is independent of the current measured bullet speed, so that a permanent optimal hit or shot probability can be achieved. The proposed correction factor for the correction of the disassembly time is based only on the shooting elements of the point of impact for the control of the weapon, namely the gun angles α, λ, the time Tf and the lead speed V0v of the projectile. This enables simple integration into existing weapon control systems, which requires minimal effort.

Fig.1

eine schematische Darstellung eines Waffensteuerungs-Systems mit der er findungsgemässen Vorrichtung,

Fig.2

einen Längsschnitt durch eine Mess- und Programmiervorrichtung,

Fig.3

ein Diagramm der Verteilung von Subprojektilen in Abhängigkeit von der Zer legungsdistanz, und

Fig.4

eine andere Darstellung des Waffensteuerungs-Systems gemäss Fig.1.

The invention is explained in more detail below using an exemplary embodiment in conjunction with the drawing. Show it.

Fig. 1

1 shows a schematic illustration of a weapon control system with the device according to the invention,

Fig. 2

a longitudinal section through a measuring and programming device,

Fig. 3

a diagram of the distribution of subprojectiles depending on the decomposition distance, and

Fig. 4

another representation of the weapon control system according to Fig.1.

In Figure 1, 1 denotes a fire control and 2 a gun. The fire control 1 consists of a search sensor 3 for the detection of a target 4 , a follow sensor 5 connected to the search sensor 3 for target detection, 3-D target tracking and 3-D target measurement, and a fire control computer 6 . The fire control computer 6 has at least one main filter 7 and a lead computing unit 9 . The main filter 7 is connected on the input side to the follow sensor 5 and on the output side to the lead computing unit 9 , the main filter 7 receiving the 3-D target data received from the follow sensor 5 in the form of estimated target data Z such as position, speed, acceleration, etc. Computing unit 9 forwards. Meteorological data can be supplied to the lead computing unit 9 via a further input Me. The meaning of the designations on the individual connections or connections is explained in more detail below on the basis of the functional description.

A computer of the gun 2 has an evaluation circuit 10 , an update computing unit 11 and a correction computing unit 12 . The evaluation circuit 10 is connected on the input side to a measuring device 14 for the projectile velocity, which is arranged at the mouth of a gun barrel 13 and is described in more detail below with reference to FIG . 2 , and is connected on the output side to the lead computing unit 9 and the update computing unit 11 . The update computing unit 11 is connected on the input side to the reserve and to the correction computing unit 9, 12 and is connected on the output side to a programmer integrated in the measuring device 14 . The correction computing unit 12 is connected on the input side to the lead computing unit 9 and on the output side to the updating computing unit 11 . A gun servo 15 and a triggering device 16 responding to a fire command are also connected to the lead computing unit 9 . The connections between the fire control 1 and the gun 2 are combined to form a data transmission, which is designated by 17 . The meaning of the designations on the individual connections between the computing units 10, 11, 12 and between the fire control system 1 and the gun 2 is explained in more detail below on the basis of the functional description. 18 and 18 ' denote a floor which is shown during a programming phase ( 18 ) and at the time of disassembly ( 18' ). The projectile 18 is a programmable projectile with primary and secondary ballistics, which is equipped with an ejection charge and a time fuse and is filled with sub-projectiles 19 .

According to FIG. 2 , a support tube 20 attached to the muzzle of the gun barrel 13 consists of three parts 21, 22, 23 . Between the first part 21 and the second or third part 22, 23 , ring coils 24, 25 are arranged for measuring the projectile speed. On the third part 23 — also called the programming part — a transmission coil 27 held in a coil body 26 is fastened. The type of attachment of the support tube 20 and the three parts 21, 22, 23 to each other is not shown and described. Lines 28, 29 are provided for supplying the ring coils. Soft iron rods 30 are arranged on the circumference of the support tube 20 for the purpose of shielding against magnetic fields which interfere with the measurement. The projectile 18 has a receiving coil 31 which is connected to a timer 34 via a filter 32 and a counter 33 . When the projectile 18 passes through the two ring coils 24, 25 , a pulse is generated in short succession in each ring coil. These pulses are fed to the evaluation circuit 10 ( FIG. 1 ), in which the projectile speed is calculated from the time interval of the pulses and a distance a between the ring coils 24, 25 . Taking the bullet speed into account, a disassembly time is calculated, as described in more detail below, which is transmitted inductively to the receiving coil 31 in digital form when the bullet 18 passes through the transmitting coil 27 for the purpose of setting the counter 32 .

In Figure 3 , Pz denotes a point of disassembly of the projectile 18 . The ejected subprojectiles are, depending on the distance from the point of decomposition Pz, evenly distributed on approximately semicircular curves of (in perspective) circular areas F1, F2, F3, F4 of a cone C. On a first abscissa I, the distance from the point of decomposition Pz is plotted in meters m, while on a second abscissa II, the area sizes of the areas F1, F2, F3, F4 are plotted in square meters m ² and their diameter in meters m. In the case of a characteristic projectile with, for example, 152 subprojectiles and an apex angle of the cone C of initially 10 °, the values plotted on the abscissa II are obtained as a function of the distance. The density of the subprojectiles on the circular areas F1, F2, F3, F4 decreases with increasing distance and is 64, 16, 7 and 4 subprojectiles per square meter with the selected ratios. Given a given disassembly distance Dz, which is based on the calculation of the disassembly time described below, for example 20 m, a target area of 3.5 m diameter would be occupied with 16 subprojectiles per square meter in the assumed example.

In the Figure 4 'the warded off target designates the preceding in a meeting place or firing position (4) and in one of the meeting place or position firing position (4' is 4, and 4) is shown.

The device described above works as follows:

The lead computation unit 9 calculates a target distance RT from a lead speed VOv and the target data Z, taking meteorological data into account for storeys with primary and secondary ballistics.

The lead speed VOv is formed, for example, from the mean value of a number of measured projectile speeds Vm supplied via the data transmission 17 , which immediately precede the current measured projectile speed Vm.

worin Vg(Tf) durch ballistische Approximation bestimmt ist und Tz die Flugzeit des Geschosses bis zum Zerlegungszeitpunkt Pz, sowie ts die Flugzeit eines in der Geschossrichtung fliegenden Subprojektiles vom Zerlegungspunkt Pz bis zum Treffpunkt Pf bedeuten (Fig. 3, 4)On the basis of a predetermined disassembly distance Dz and taking into account the projectile velocity Vg (Tf) which is dependent on a hit time Tf, a disassembly time Tz of the projectile can be determined according to the following relationships: $$\text{Dz = Vg (Tf) ∗ ts and Tz = Tf - ts}$$

where Vg (Tf) is determined by ballistic approximation and Tz is the flight time of the projectile to the disassembly time Pz, and ts is the flight time of a subprojectile flying in the projectile direction from the disassembly point Pz to the meeting point Pf ( Fig. 3, 4 )

The lead computing unit 9 also determines a gun angle α of the azimuth and a gun angle I of the elevation. The quantities α, λ, Tf and VOv are referred to as shooting elements of the meeting point and are fed to the correction computing unit 12 via the data transmission 17 . The shooting elements α and λ are also fed to the gun servo 15 and the shooting elements VOv and Tf or Tz to the update computing unit 11 .

The calculations described above are repeated in cycles, so that the latest data α, λ, Tz or Tf and VOv are available for a specific period of validity in the current cycle i.

Between the clock values, the current (running) time (t) is interpolated or extrapolated.

The correction arithmetic unit 12 calculates a correction actuator K at the beginning of each cycle i with the latest set of shooting elements α, λ, Tz or Tf and VOv, for which purpose a determination equation for the correction factor K is developed as described in more detail below.

ist $\overrightarrow{\mathit{\text{v}}}$

_rel die relative Geschwindigkeit zwischen Geschoss und Ziel und

die Ableitung der Geschossposition nach dem Betrag der Anfangsgeschwindigkeit. Bei Annahme einer gestreckten Ballistik, bei der die Richtung des Vektors

ungefähr gleich der Richtung des Geschützrohres 13 ist kann

gesetzt werden. Hierbei wird der Betrag der Komponente der VorhaltAnfangsgeschwindigkeit v _o in Rohrrichtung als konstant angenommen. Das heisst $\mathit{\text{TG}}\text{=}\mathit{\text{TG}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{o}}}\text{)}$

und $\mathit{\text{P}}\overrightarrow{\mathit{\text{o}}}\mathit{\text{s}}\text{=}\mathit{\text{P}}\overrightarrow{\mathit{\text{o}}}\mathit{\text{s}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{o}}}\text{)}$

Zu beachten ist jedoch, dass ${\overrightarrow{\mathit{\text{v}}}}_{\mathit{\text{o}}}\text{=}{\overrightarrow{\mathit{\text{v}}}}_{\mathit{\text{o}}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{o}}}\text{)}$

wegen der Bewegung des Geschützrohres 13 trotzdem von der Zeit abhängig ist, was durch die ballistische Lösung

ausgedrückt wird. Die Treffbedingung lautet dann

Die Ableitung der Gleichung Gl.10 nach t_o liefert

was eine Zerlegung der Zielgeschwindigkeit in die Geschossgeschwindigkeit und einen Vektor $\overrightarrow{\mathit{\text{C}}}$

. darstellt, wobei

ist. Aus der allgemeinen Theorie ist bekannt, dass unter den gegebenen Voraussetzungen der Ausdruck in Gleichung Gl.11.1

ist. Ausserdem ist die Rohrgeschwindigkeit

klein, so dass der Vektor

in Gleichung Gl.11.1 als vernachlässigbar klein betrachtete werden darf. Nach der allgmeinen Definition der Ableitung gilt für D₃ in Gleichung Gl.11.1

Bei Vernachlässigung der Elevation des Geschützrohes 13 ist

so dass sich annähernd

ergibt. Der Punkt $\overrightarrow{\mathit{\text{p}}}$

_G (TG(t _o ), P $\overrightarrow{\mathit{\text{o}}}$

s(t _o ), $\overrightarrow{\mathit{\text{v}}}$

_o (t _o + h)) bewegt sich somit annähernd auf einer Kreisbahn in einer Ebene (Drehebene), welche durch die Vektoren $\overrightarrow{\mathit{\text{p}}}$

_G (TG(t _o ), P $\overrightarrow{\mathit{\text{o}}}$

s(t _o ), $\overrightarrow{\mathit{\text{v}}}$

_o (t _o + h))aufgespannt wird. Damit kann für Gleichung Gl.12

geschrieben werden, wobei $\overrightarrow{\text{ω}}$

der Drehvektor senkrecht zur Drehebene ist. Hierbei wird angenommen, dass die Winkelgeschwindigkeit des Geschützrohres 13 um seine momentane Drehachse dem Betrag nach gleich der Winkelgeschwindigkeit der $\overrightarrow{\mathit{\text{p}}}$

_G (TG(t _o ), P $\overrightarrow{\mathit{\text{o}}}$

s(t _o ), $\overrightarrow{\mathit{\text{v}}}$

_o (t _o + h)) ist, so dass sich

ergibt. Unter der zusätzlichen Annahme, dass im Fall gestreckter Ballistik die Geschossgeschwindigkeit ungefähr parallel zur Zielrichtung ist, das heisst

ist, wird aus Gleichung Gl.11 eine die Zerlegung der Zielgeschwindigkeit in zwei orthogonale Komponenten ausdrückende Gleichung Gl.15 gewonnen:

Durch Einsetzen der Gleichung Gl.9 in Gleichung Gl.8 und unter Berücksichtigung der Definition für $\overrightarrow{\mathit{\text{v}}}$

_rel (v _o )

und der Definitionen

ergibt sich

In a definition of the correction factor K

is $\overrightarrow{\mathit{\text{v}}}$

_rel the relative speed between floor and target and

the derivation of the projectile position according to the amount of the initial speed. Assuming a stretched ballistics in which the direction of the vector

is approximately equal to the direction of the gun barrel 13

be set. The amount of the component of the lead initial speed v _o in the pipe direction is assumed to be constant. This means $\mathit{\text{TG}}\text{=}\mathit{\text{TG}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{O}}}\text{)}$

and $\mathit{\text{P}}\overrightarrow{\mathit{\text{O}}}\mathit{\text{s}}\text{=}\mathit{\text{P}}\overrightarrow{\mathit{\text{O}}}\mathit{\text{s}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{O}}}\text{)}$

However, it should be noted that ${\overrightarrow{\mathit{\text{v}}}}_{\mathit{\text{O}}}\text{=}{\overrightarrow{\mathit{\text{v}}}}_{\mathit{\text{O}}}\text{(}{\mathit{\text{t}}}_{\mathit{\text{O}}}\text{)}$

because of the movement of the gun barrel 13 is still dependent on the time, what by the ballistic solution

is expressed. The meeting condition is then

The derivation of the equation Eq.10 after t _o gives

which is a breakdown of the target speed into the bullet speed and a vector $\overrightarrow{\mathit{\text{C.}}}$

. represents, where

is. It is known from general theory that under the given conditions the expression in equation Eq.11.1

is. In addition, the pipe speed

small, so the vector

in Equation 11.1 can be considered negligible. According to the general definition of the derivative, D ₃ in Equation 11.1 applies

If the elevation of the gun barrel 13 is neglected

so that approximate

results. The point $\overrightarrow{\mathit{\text{p}}}$

_G (TG (t _o), P $\overrightarrow{\mathit{\text{O}}}$

s (t _o), $\overrightarrow{\mathit{\text{v}}}$

_o ( t _o + h )) thus moves approximately on a circular path in a plane (plane of rotation), which is represented by the vectors $\overrightarrow{\mathit{\text{p}}}$

_G (TG (t _o), P $\overrightarrow{\mathit{\text{O}}}$

s (t _o), $\overrightarrow{\mathit{\text{v}}}$

_o ( t _o + h )) is spanned. For equation Eq. 12

be written, whereby $\overrightarrow{\text{ω}}$

the rotation vector is perpendicular to the rotation plane. It is assumed here that the angular velocity of the gun barrel 13 around its instantaneous axis of rotation is equal in amount to the angular velocity of the $\overrightarrow{\mathit{\text{p}}}$

_G (TG (t _o), P $\overrightarrow{\mathit{\text{O}}}$

s (t _o), $\overrightarrow{\mathit{\text{v}}}$

_o ( t _o + h )) is such that

results. With the additional assumption that in the case of stretched ballistics the bullet speed is approximately parallel to the target direction, that is

an equation Eq. 15 expressing the decomposition of the target speed into two orthogonal components is obtained from equation Eq. 11:

By inserting equation Eq.9 into equation Eq.8 and taking into account the definition for $\overrightarrow{\mathit{\text{v}}}$

_rel ( v _o )

and the definitions

surrendered

sowie

so dass

wird. Durch Kürzen mit

wird Gleichung Gl.16 vereinfacht, wobei sich der Korrekturfaktor K zu

ergibt. In Gleichung Gl.17 kann die Ableitung der Flugzeit

von der Feuerleitung 1 mittels verschiedener mathematischer Methoden berechnet werden. Nach Gleichung Gl.13 ist ω² eine bekannte Funktion von α̇(t _o ), λ(t _o ) und λ̇(t _o ). Diese Grössen können entweder berechnet oder direkt am Geschütz 2 gemessen werden.From equations Eq. 14 and Eq.15, taking into account the definitions for p _G , v _G and v _Z

such as

so that

becomes. By shortening with

Equation Eq. 16 is simplified, with the correction factor K increasing

results. Equation Eq.17 can be used to derive the flight time

can be calculated by the fire control 1 using various mathematical methods. According to equation Eq. 13, ω ^{2 is} a known function of α̇ ( t _o ), λ ( t _o ) and λ̇ ( t _o ). These sizes can either be calculated or measured directly on gun 2.

sind durch die Ballistik gegeben. Es sind Funktionen in erster Ordnung der Flugzeit und in zweiter Ordnung der Rohrelevation, welche vernachlässigbar sein kann. Für die Ermittlung dieser Grössen kann beispielsweise eine Lösung nach d'Antonio angewendet werden. Dieser Ansatz liefert

wobei $$\mathit{\text{q}}\text{:=}{\mathit{\text{cw}}}_{\mathit{\text{n}}}\text{·}\frac{\text{Luftdichte·Geschossquerschnitt}}{\text{2·Geschossmasse}}$$

ist und $\overrightarrow{\mathit{\text{v}}}$

_n eine Geschwindigkeit (nominelle Anfangsgeschwindigkeit des Geschosses) bedeutet, die sich auf den cw-Wert bezieht. Durch Einsetzen der Gleichungen Gl.18 und Gl.19 in Gleichung Gl.17 ergibt sich der Korrekturfaktor K zu

wobei die Grössen TG,

α, λ, α̇, λ̇ und $\overrightarrow{\mathit{\text{v}}}$

_o sich auf den Zeitpunkt t_o beziehen.The sizes

are given by ballistics. There are functions in the first order of flight time and in the second order of pipe elevation, which can be negligible. For example, a solution according to d'Antonio can be used to determine these variables. This approach delivers

in which $$\mathit{\text{q}}\text{: =}{\mathit{\text{cw}}}_{\mathit{\text{n}}}\text{·}\frac{\text{Airtight <figure-callout id="2" label="floor cross section" filenames="imgf0002.png" state="{{state}}">floor cross section</figure-callout>}}{\text{2 · storey mass}}$$

is and $\overrightarrow{\mathit{\text{v}}}$

_{n means} a velocity (nominal initial velocity of the projectile) which refers to the drag coefficient. By inserting equations Eq.18 and Eq.19 into equation Eq.17, the correction factor K results

the sizes TG ,

α, λ, α̇, λ̇ and $\overrightarrow{\mathit{\text{v}}}$

_o refer to the time t _o .

  ein Vektor
∥ $\overrightarrow{\mathit{\text{v}}}$

∥  Norm des Vektors
〈 $\overrightarrow{\mathit{\text{u}}}$

, $\overrightarrow{\mathit{\text{v}}}$

〉  Skalarprodukt
$\overrightarrow{\mathit{\text{u}}}$

× $\overrightarrow{\mathit{\text{v}}}$

  Vektorprodukt
Id  Einheitsmatrix
·  skalare oder Matrixmultiplikation
g := A.  die Grösse g wird definiert als Ausdruck A
g = g(x ₁ , ..., x _n )  die Grösse g hängt ab von x₁,.......,x_n
t ↦ g(t)  Zuordnung (t wird die Auswertung von g an der Stelle t zugeordnet)
ġ  Ableitung von g nach der Zeit
D _i g(x ₁ , ...,x _n )  partielle Ableitung von g nach der i-ten Variablen
$\frac{\text{∂}}{\text{∂t}}$

g(t, x ₁ , ..., x _n )  partielle Ableitung von g nach der Zeit t
lim _{h →0} A(h)  Limes des Ausdruckes A für h gegen 0
inf _t M  Infimum der Menge M über alle t
$\overrightarrow{\mathit{\text{p}}}$

_G , $\overrightarrow{\mathit{\text{v}}}$

_G , $\overrightarrow{\mathit{\text{a}}}$

_G   Position,Geschwindigkeit,Beschleunigung des Geschosses
$\overrightarrow{\mathit{\text{p}}}$

_Z , $\overrightarrow{\mathit{\text{v}}}$

_Z , $\overrightarrow{\mathit{\text{a}}}$

_Z   Position,Geschwindigkeit,Beschleunigung des Zieles
$\overrightarrow{\mathit{\text{p}}}$

_rel , $\overrightarrow{\mathit{\text{v}}}$

_rel , $\overrightarrow{\mathit{\text{a}}}$

_rel   relative Position,Geschwindigkeit,Beschleunigung Geschoss-Ziel
P $\overrightarrow{\mathit{\text{o}}}$

s  Position der Rohrmündung
α, λ  Azimut und Elevation des Geschützrohres
$\overrightarrow{\mathit{\text{v}}}$

_o   Vorhalt-Anfangsgeschwindigkeit des Geschosses
v _o   Betrag der Komponente der Vorhalt-Anfangsgeschwindigkeit der Geschosses in Rohrrichtung
v _m   Betrag der Komponente der effektiven Anfangsgeschwindigkeit des Geschosses in Rohrrichtung
TG  Vorhalt Flugzeit des Geschosses
t*  Flugzeit des Geschosses
t _o   Zeitpunkt zu dem das Geschoss die Rohrmündung passiert.The mathematical or physical notation used above means:
$\overrightarrow{\mathit{\text{v}}}$

a vector
∥ $\overrightarrow{\mathit{\text{v}}}$

∥ norm of the vector
〈 $\overrightarrow{\mathit{\text{u}}}$

, $\overrightarrow{\mathit{\text{v}}}$

〉 Dot product
$\overrightarrow{\mathit{\text{u}}}$

× $\overrightarrow{\mathit{\text{v}}}$

Vector product
Id unit matrix
· Scalar or matrix multiplication
g : = A. size g is defined as expression A
g = g ( x ₁ , ..., x _n ) the size g depends on x ₁ , ......., x _n
t ↦ g ( t ) assignment (t is assigned the evaluation of g at point t)
ġ derivative of g over time
D _i g ( x ₁ , ..., x _n ) partial derivative of g according to the i-th variable
$\frac{\text{∂}}{\text{∂t}}$

g ( t , x ₁ , ..., x _n ) partial derivative of g after time t
lim _{h → 0} A ( h ) Limes of the expression A for h against 0
inf _t M Infimum of the set M over all t
$\overrightarrow{\mathit{\text{p}}}$

_G , $\overrightarrow{\mathit{\text{v}}}$

_G , $\overrightarrow{\mathit{\text{a}}}$

_G position, speed, acceleration of the projectile
$\overrightarrow{\mathit{\text{p}}}$

_Z , $\overrightarrow{\mathit{\text{v}}}$

_Z , $\overrightarrow{\mathit{\text{a}}}$

_Z position, speed, acceleration of the target
$\overrightarrow{\mathit{\text{p}}}$

_rel , $\overrightarrow{\mathit{\text{v}}}$

_rel , $\overrightarrow{\mathit{\text{a}}}$

_rel relative position, speed, acceleration floor-target
P $\overrightarrow{\mathit{\text{O}}}$

s Position of the pipe mouth
α, λ azimuth and elevation of the gun barrel
$\overrightarrow{\mathit{\text{v}}}$

_o Projectile initial velocity of the projectile
v _o Amount of the component of the initial initial velocity of the projectile in the pipe direction
v _m Amount of the component of the effective initial velocity of the projectile in the pipe direction
TG lead flight time of the projectile
t * flight time of the projectile
t _o time at which the projectile passes the pipe muzzle.

The update arithmetic unit 11 calculates a corrected disassembly time Tz (Vm) from the correction factor K supplied by the correction arithmetic unit 12, the current measured projectile speed Vm supplied by the evaluation circuit 10 and the lead speed Vov supplied by the lead computing unit 9 the relationship $$\text{Tz (Vm) = Tz + K ∗ (Vm-VOv).}$$

The corrected decomposition time Tz (Vm) is interpolated or extrapolated depending on the validity for the current running time t. The newly calculated disassembly time Tz (Vm, t) is fed to the transmitter coil 27 of the programming part 23 of the measuring device 14 and, as already described above with reference to FIG. 2, is transmitted inductively to a projectile 18 flying by.

With the correction of the disassembly time Tz, the disassembly distance Dz (Fig. 3, 4) can be independent of the scatter of the bullet speed be kept constant, so that an optimal meeting or Probability of shooting can be achieved.

gesetzt werden, wobei dieser Ansatz in erster Ordnung bei Berücksichtigung der Fallwinkel für eine kurze Ballistik zum gleichen Ergebnis für den Korrekturfaktor K führt.Instead of equation Eq. 9, if stretched ballistics is assumed, it can also

are set, this approach leading to the same result for the correction factor K taking into account the drop angle for a short ballistics.

Reference list

1

Fire control

2nd

gun

3rd

Search sensor

4th

target

5

Follow sensor

6

Fire control computer

7

Main filter

9

Lead computing unit

10th

Evaluation circuit

11

Update processing unit

12th

Correction computing unit

13

Gun barrel

14

Measuring device

15

Gun servo

16

Release device

17th

Data transmission

18th

bullet

18 '

bullet

19th

Subprojectile

20th

Support tube

21

First part

22

Second part

23

third part

24th

Ring coil

25th

Ring coil

26

Bobbin

27

Transmitter coil

28

management

29

management

30th

Soft iron bars

31

Receiving coil

32

filter

33

counter

34

Timer

a

distance

Pz

Position of the decomposition point

F1-F4

Circular areas

C.

cone

I.

First abscissa

II

Second abscissa

Dz

Disassembly distance

RT

Hit distance

VOv

Lead speed

Vm

Current measured bullet speed

Tz

Disassembly time

ts

Subprojectile flight time

Pf

meeting point

α

Gun angle

λ

Gun angle

Tf

Meeting time

TG

Flight time

Tz (Vm)

Corrected disassembly time

Me

Entrance (Meteo)

Z.

Target dates

Claims (3)

Method for calculating the disassembly time of a programmable projectile, whereby the calculation calculates at least one target distance (RT) to a target object determined from sensor data, a projectile speed (Vm) measured at the muzzle of a gun barrel (13) and a given disassembly distance (Dz) between a meeting point ( Pf) and a decomposition point (Pz) of the floor (18)
characterized,
that the given disassembly distance (Dz) is kept constant by correcting the disassembly time (Tz), the correction by the relationship $$\text{Tz (Vm) = Tz + K ∗ (Vm-Vov)}$$

takes place, and being Tz (Vm) the corrected disassembly time, Tz the disassembly time, K a correction factor, Vm is the current measured bullet speed and VOv mean a lead rate of the projectile. Method according to claim 1,
characterized,
that the correction factor (K) based on the definition

and the derivation of the projectile position according to the amount of the initial speed when a stretched ballistics is assumed

as well as the ballistic solution

and the meeting condition

by means of the following calculation steps in relation to a flight time (TG) of the projectile, the gun angles (α, λ) and the lead speed, - Differentiate the equation Eq.10 after the time t _o delivers

where equation Eq.11 divides the target speed into the bullet speed and a vector ( $\overrightarrow{\mathit{\text{C.}}}$

), and where

is - neglect of expression

in equation Eq.11.1, - Define the derivative D ₃ in equation Eq.11.1

- neglect the elevation of the gun barrel (13), wherein

is and approximate

results in equation Eq.12 as

can be written with $\overrightarrow{\text{ω}}$

a rotation vector is perpendicular to a rotation plane, - Assume that the angular velocity of the gun barrel (13) about its instantaneous axis of rotation is equal to the amount of the angular velocity of the $\overrightarrow{\mathit{\text{p}}}$

_G (TG (t _o), P $\overrightarrow{\mathit{\text{O}}}$

s (t _o), $\overrightarrow{\mathit{\text{v}}}$

_o ( t _o + h )) is such that

results in - Assume that the ball speed is approximately parallel to the target direction when the ballistics are stretched, that is

and an equation Eq. 15 expressing the decomposition of the target speed into two orthogonal components is obtained from equation Eq. 11

- inserting equation Eq.9 into equation Eq.8 taking into account the definition of

and the definitions

results

- taking into account the definitions for p _G , v _G and v _Z results from equations Eq. 14 and Eq. 15

such as

so that

becomes, - shorten equation Eq. 16 with

so that the correction factor (K) increases

results in $\overrightarrow{\mathit{\text{p}}}$

_G , $\overrightarrow{\mathit{\text{v}}}$

_G , $\overrightarrow{\mathit{\text{a}}}$

_G position, speed, acceleration of the projectile $\overrightarrow{\mathit{\text{p}}}$

_Z , $\overrightarrow{\mathit{\text{v}}}$

_Z , $\overrightarrow{\mathit{\text{a}}}$

_Z position, speed, acceleration of the target $\overrightarrow{\mathit{\text{p}}}$

_rel , $\overrightarrow{\mathit{\text{v}}}$

_rel , $\overrightarrow{\mathit{\text{a}}}$

_rel relative position, speed, acceleration floor-target P $\overrightarrow{\mathit{\text{O}}}$

s Position of the pipe mouth α, λ azimuth and elevation of the gun barrel $\overrightarrow{\mathit{\text{v}}}$

_o Projectile initial velocity of the projectile v _o Amount of the component of the initial initial velocity of the projectile in the pipe direction v _m Amount of the component of the effective initial velocity of the projectile in the pipe direction TG lead flight time of the projectile t * flight time of the projectile t _o mean when the bullet passes the pipe muzzle. Method according to claim 2,
characterized,
that the sizes

of equation Eq.17 according to the equations

can be determined, whereby $$\mathit{\text{q}}\text{: =}{\mathit{\text{cw}}}_{\mathit{\text{n}}}\text{·}\frac{\text{Airtight floor cross section}}{\text{2 · storey mass}}$$

and $\overrightarrow{\mathit{\text{v}}}$

_{n is} a bullet velocity related to the drag coefficient, and that equations Eq.18 and Eq.19 are used in Equation Eq.17, where

results.

Images