U.S. patent application number 14/059023 was filed with the patent office on 2014-03-06 for apparatus and method for programming a projectile.
The applicant listed for this patent is RHEINMETALL AIR DEFENCE AG. Invention is credited to Aldo ALBERTI, Kurt MUELLER.
Application Number | 20140060298 14/059023 |
Document ID | / |
Family ID | 45804966 |
Filed Date | 2014-03-06 |
United States Patent
Application |
20140060298 |
Kind Code |
A1 |
MUELLER; Kurt ; et
al. |
March 6, 2014 |
APPARATUS AND METHOD FOR PROGRAMMING A PROJECTILE
Abstract
A measurement apparatus is provided, which is included on a
measurement and programming basis for a projectile, which detects
the fields and/or signals which emerge/originate from a programming
coil, and is electrically connected to an evaluation device which
itself evaluates these detected values. These values can then be
taken into account for the programming of the projectile.
Inventors: |
MUELLER; Kurt; (Zuerich,
CH) ; ALBERTI; Aldo; (Winterthur, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
RHEINMETALL AIR DEFENCE AG |
Zuerich |
|
CH |
|
|
Family ID: |
45804966 |
Appl. No.: |
14/059023 |
Filed: |
October 21, 2013 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2012/055531 |
Mar 28, 2012 |
|
|
|
14059023 |
|
|
|
|
Current U.S.
Class: |
89/6.5 |
Current CPC
Class: |
F42C 11/00 20130101;
F42C 11/065 20130101; F42C 17/04 20130101; G01P 3/665 20130101 |
Class at
Publication: |
89/6.5 |
International
Class: |
F42C 11/00 20060101
F42C011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 19, 2011 |
DE |
DE102011018248.9 |
Claims
1. An apparatus for programming a programmable projectile, the
apparatus comprising: at least one programming coil; and a
measurement apparatus configured to detect fields and/or signals
which emerge/originate from the programming coil and is
electrically connected to an evaluation device, which evaluates
these detected values.
2. The apparatus according to claim 1, wherein the detected values
are made available as correction values for the programming of the
projectile.
3. The apparatus according to claim 1, wherein the measurement
apparatus has a coil with one or more turns around a muzzle opening
of a tube weapon.
4. The apparatus according to claim 1, further comprising a
conductor track configured as a circuit coil winding, and wherein
the measurement apparatus is a printed circuit.
5. The apparatus according to claim 1, wherein the measurement
apparatus located such that it does not cover the unobstructed
opening of the barrel muzzle.
6. The apparatus according to claim 1, wherein the measurement
apparatus is included in an attachment ring that is configured to
be adhesively bonded to an end surface of a tube-weapon muzzle.
7. The apparatus according to claim 6, wherein the attachment ring
is equipped with an enlarged area.
8. The apparatus according to claim 6, wherein the attachment ring
is a cap.
9. A method for programming a programmable projectile, the method
comprising: providing at least one programming coil; providing a
measurement apparatus that detects fields and/or signals which
emerge/originate from the programming coil; and evaluating the
detected fields and/or signals in an evaluation device.
10. The method according to claim 9, wherein the values are made
available as correction values for the programming of the
projectile.
Description
[0001] This nonprovisional application is a continuation of
International Application No. PCT/EP2012/055531, which was filed on
Mar. 28, 2012, and which claims priority to German Patent
Application No. DE 10 2011 018 248.9, which was filed in Germany on
Apr. 19, 2011, and which are both herein incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an apparatus for
measurement of electromagnetic fields on and/or within a
programming device which, for example, is included on the muzzle of
a tube weapon, in particular having a measurement apparatus on a
programming device for an air burst munition (ABM), that is to say
having a field test appliance on a measurement and programming
basis. The measurement apparatus can measure fields and/or signals
from the programming coil, thus making it possible to check the
correct operation of the programming coil, the programming signal
and the time correlation with the projectile, as well as the
programming of a projectile itself. In special cases, these values
can then be taken into account for the programming of the
projectile.
[0004] 2. Description of the Background Art
[0005] The term a tube weapon can denote both guns and rocket
launch tubes. The term projectile is intended to mean all airborne
vehicles which can be launched or fired from a weapon barrel, that
is to say ballistic projectiles and projectiles which at least
partially propel themselves. The term ballistic projectiles means
normal conventional projectiles which detonate on impact, such as
projectiles which can be fuzed and/or programmed, and, for example,
detonate in flight. The projectiles may be spin-stabilized and/or
fin-stabilized and may, for example, be in the form of discarding
sabot projectiles, primary projectiles which carry a plurality of
secondary projectiles in them, or exercise projectiles with a core
and casing.
[0006] In general gunnery, the muzzle velocity of a projectile is
normally referred to as V.sub.0, and is also referred as the
V.sub.0 velocity. This is therefore the velocity at which a
projectile launched or fired from a tube weapon moves on its
trajectory relative to the weapon barrel when it emerges from the
weapon barrel. The flight duration, the firing distance and the
hit-point position are dependent, inter alia, on the V.sub.0
velocity. However, precise knowledge of the muzzle velocity V.sub.0
is particularly important in the context of programmable
projectiles, since the time at which a programming code is
transmitted to a projectile in order to achieve the desired weapon
effect depends on the muzzle velocity, V.sub.0. The muzzle velocity
V.sub.0 also depends on the weight and the temperature of the
propellant charge.
[0007] A theoretical muzzle velocity V.sub.0(theor.) can be
determined by calculation if all the relevant data relating to the
weapon, the weapon barrel and the projectile to be fired or
launched is known. However, the muzzle velocity V.sub.0 differs
from the theoretically calculated muzzle velocity V.sub.0(theor.).
In addition, the V.sub.0 velocity is reduced as a consequence of
weapon barrel wear. Therefore, the actual muzzle velocity is
preferably in each case measured on firing, in order to correct the
azimuth and elevation of the weapon barrel as necessary for the
target to be attacked, and/or in order to appropriately program the
projectile, or at least the subsequent projectiles.
[0008] An airburst munition (ABM) is a munition type which breaks
up during the flight phase without any need to strike a target
object or to be in the vicinity of a target object. For this
purpose, a suitable mechanism is used to fire a break-up charge
within this munition and to cause it to explode. If the muzzle
velocity of the ABM is known sufficiently accurately, the desired
range can be determined via an indication of a time after which the
break-up charge is intended to be fired after leaving the muzzle.
Because of the natural scatter in the muzzle velocities of ABM, it
is particularly important, for this type of munition, to determine
the initial velocity at the muzzle (V.sub.0) with sufficient
accuracy.
[0009] Various apparatuses and methods are known for measurement of
the actual V.sub.0 velocity. Frequently, the measurement of the
V.sub.0 velocity is based on a gate principle. A V.sub.0
measurement such as this is known from EP 0 108 973 B1, which
corresponds to U.S. Pat. No. 4,677,376. In this case, two coils are
used, which are arranged at a known distance from one another, to
be precise after the exit cross section of the weapon barrel, seen
in the direction of flight of the projectile. These coils and the
distance between them form a measurement base path. The coils are
in general arranged at least approximately concentrically with
respect to the longitudinal axis of the weapon barrel, and their
internal diameter is somewhat larger than the calibre of the weapon
barrel. The coils are connected to current sources, thus resulting
in a magnetic field in the area of each coil, and an induced
voltage can be tapped off as the projectile passes through. While a
projectile is flying through the area of the coils, the magnetic
field is disturbed, and the voltage which can be tapped off changes
as a function of the relative position of the projectile with
respect to the coil. CH 691 143 A5 deals with the same subject.
[0010] Therefore, if the V.sub.0 of the individual projectile is
determined at the muzzle of the gun, then, after the appropriate
break-up time has been calculated, this value can be programmed
into the projectile via a programming unit, which is located
downstream in the direction of the projectile flight path, as a
result of which the projectile is broken up by the break-up charge
at the desired point. One such system is known, for example, from
EP 0 802 390 A1 (which corresponds to U.S. Pat. No. 5,814,755), EP
0 802 392 A1 (which corresponds to U.S. Pat. No. 5,814,756) and EP
0 802 391 A1 (which corresponds to U.S. Pat. No. 5,834,675), which
are all herein incorporated by reference. In this case, the
projectile passes through a measurement path in the area of the
muzzle, which measurement path is formed by two coils arranged one
behind the other, and produces a time-dependent voltage signal in
each of these coils. If the distance between the coils is known,
the projectile velocity can be determined from these signals. The
appropriate break-up time is calculated in a computation unit, and
is programmed in the projectile via a third coil.
[0011] In order to make it possible to set the time fuzes for
breaking up the projectile with the desired accuracy, it is
necessary, according to the teaching of EP 0 467 055 A1, which
corresponds to U.S. Pat. No. 5,117,732, which is incorporated
herein by reference, to transmit at least 12 bits from the
transmission coil of the programming device to the receiving coil
in the projectile. By way of example, in the case of a muzzle
velocity of 1200 m/s, the receiving coil in the projectile passes
by the transmission coil, which is attached to the weapon barrel
muzzle, in a relatively short time, as a result of which only a
short time is available for transmission of the information from
the transmission coil to the receiving coil. At the same time, the
transmission time window must be chosen such that the projectile is
located within the transmission coil at that time.
SUMMARY OF THE INVENTION
[0012] It is therefore an object of the present invention to
provide an apparatus which can be used for accurate programming
while a shot is being fired.
[0013] In an embodiment, the invention is based on the idea of
checking the correct operation of the programming coil, the
programming signal and the time correlation with the projectile as
well as the programming of a projectile itself. This can be done by
detection of the fields and/or signals of the programming coil.
This information can then be taken into account in the programming.
The measurement apparatus according to the invention furthermore
makes it possible to also detect disturbance fields from further
components of the tube weapon, as well as disturbance fields which
act on the tube weapon from the outside. Furthermore, it is also
possible to check for active incident radiation from, for example,
Natel, radar, active jamming devices and switching jammers. These
are further influences which can now be taken into account during
programming. Admittedly, test devices which can detect fields and
signals of a programming coil are already known, for example by the
term base test appliance, but these are restricted to laboratory
environments, that is to say they do not measure the situation of a
real shot, and the possible correction associated therewith.
[0014] In order to implement the idea within the scope of an
existing programming device, for example in the area of the muzzle
of a tube weapon and preferably even on the programming coil for
the munition itself, an additional measurement apparatus is
provided, that is independent of the programming coil, can detect
the signals which are present in the area of the programming coil,
and in particular the signals emitted by the programming coil, and
can pass these to a measurement evaluation device. The system is
designed as a purely passive system.
[0015] In the simplest case, this measurement apparatus may have a
coil having one or more turns around the muzzle opening of the tube
weapon. The coil is functionally connected to a fundamentally known
signal receiving and signal processing device, for example via a
wire connection.
[0016] The coil can be positioned such that, on the one hand, it
does not cover the unobstructed opening of the barrel muzzle, while
nevertheless at the same time makes it possible to detect
sufficiently well the fields which emerge/originate from the
programming coil with a low field strength. For this purpose, they
must be positioned outside the metallic screening of the
programming coil.
[0017] The number of coil turns may be one or more. Since the
number of turns influences the response time of the coil, the turns
are chosen on the basis of the flank gradient of the signal to be
detected. The fastest response behaviour is achieved with a single
coil winding. Better signal sensitivities are achieved with a
plurality of windings--the best solution should in each case be
chosen depending on the signal strength and the gradient. The
windings may either be in the form of wire in a surrounding
structure or, alternatively and particularly preferably, may be
implemented in the form of a printed circuit board ("print").
[0018] An electrically non-conductive material should be provided
for the material surrounding the coil, for example non-conductive
plastics or epoxy materials. At the same time, it is advantageous
for this material to have low density, which therefore means only a
small additional mass in the area of the muzzle since, as is known,
additional masses in the muzzle area influence the dynamic and
static behaviour of the tube weapon.
[0019] The measurement apparatus can be attached to the programming
coil assembly via an adhesive joint, a push joint or else as a
printed embodiment on a surface. The positioning can be considered
in many ways.
[0020] This results, inter alia, in the further advantages of a
good signal evaluation capability: bit patterns and possible
interruptions, signal strengths, attenuations and single-bit tests,
that is to say whether correct bits have been set. Furthermore, the
time window/time instant of programming (within 20 .mu.s) can be
tested, and the programming basis can be tested during actual
firing. An independent functional and quality test of the
programming base can also be carried out. This is used as a referee
tool for failure (to break up in the intended target region):
>caused in the programming, or in the munition?< and the
documentation of the base characteristics during acceptance
firing.
[0021] A measurement apparatus is proposed which is included on a
measurement and programming basis for the programming of a
projectile (13), which can detect the fields and/or signals which
emerge/originate from a programming coil. These "detected" values
are evaluated in an evaluation device, and can then also be made
available for programming the projectile. This therefore makes it
possible not only to make decisions on the method of operation of
the programming coil as such, but also to implement corrections,
when this is electronically possible.
[0022] Further scope of applicability of the present invention will
become apparent from the detailed description given hereinafter.
However, it should be understood that the detailed description and
specific examples, while indicating preferred embodiments of the
invention, are given by way of illustration only, since various
changes and modifications within the spirit and scope of the
invention will become apparent to those skilled in the art from
this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention will become more fully understood from
the detailed description given hereinbelow and the accompanying
drawings which are given by way of illustration only, and thus, are
not limitive of the present invention, and wherein:
[0024] FIG. 1 shows a longitudinal section through a measurement
and programming device according to the conventional art,
[0025] FIG. 2 shows a sectional illustration of an embodiment of a
measurement apparatus for measurement of the field and/or of the
signals of at least the coil of the programming device,
[0026] FIG. 3 shows a sectional illustration of an embodiment,
[0027] FIG. 4 shows a sectional illustration of an embodiment,
and
[0028] FIG. 5 shows a sectional illustration of an embodiment.
DETAILED DESCRIPTION
[0029] FIG. 1 shows a supporting tube 20, which is attached
according to the prior art to the muzzle of a gun barrel 13 and
includes three parts 21, 22, 23. Annular coils 24, 25 for the
measurement of the projectile velocity are arranged between the
first part 21 and the second and/or third parts 22, 23. A
transmission coil 27, which is held in a coil former 26, is
attached to the third part 23--also referred to as the programming
part. Lines 28, 29 are provided for feeding the annular coils.
Soft-iron bars 30 are arranged on the circumference of the
supporting tube 20, for screening against magnetic fields which
interfere with the measurement. The projectile 18 has a receiving
coil 31, which is connected to a time fuse 34 via a filter 32 and a
counter 33. When the projectile 18 passes through the two annular
coils 24, 25, a pulse is produced at short successive intervals in
each annular coil. These pulses are fed to an evaluation circuit
(not illustrated), in which the projectile velocity is calculated
from the time interval between the pulses and the distance a
between the annular coils 24, 25. The projectile velocity is used
to calculate a break-up time, which is transmitted inductively to
the receiving coil 31 in a suitable form while the projectile 18 is
passing through the transmission coil 27, in order to set the
counter 32 etc.
[0030] FIG. 2 describes a first embodiment of the apparatus 10
according to the invention. In this case, this section drawing
represents the muzzle 11 of the tube weapon, which is formed by a
component 1 which extends in a circular form around the barrel
centre axis 2. At least one winding 5 of the measurement apparatus
10 is incorporated within an electrically non-conductive attachment
ring 4. The ring 4 is preferably adhesively bonded to the end
surface of the tube-weapon muzzle, and in the process isolates the
winding 5 from the electrically conductive closure cap 3 on the
tube weapon.
[0031] FIG. 3 describes a second embodiment of the apparatus 10'
according to the invention. In this case, this section drawing
represents the muzzle 11 of the tube weapon, which is formed by the
component 1 which extends in a circular shape around the barrel
centre axis 2. At least one winding 5 of the measurement apparatus
10 is incorporated within an electrically non-conductive attachment
ring 12. The ring 12 is equipped with an enlarged area, in order to
improve the adhesive joint to the component 1 and the closure cap 3
on the tube weapon.
[0032] FIG. 4 describes a third embodiment of the apparatus
according to the invention. In this case, the attachment ring 14 is
in the form of a cap which can be placed over the muzzle 10 of the
tube weapon. This improves the mechanical retention of the
measurement apparatus 5 according to the invention on the tube
weapon further in comparison to the previous embodiments.
[0033] FIG. 5 describes a fourth, particularly preferred,
embodiment of the apparatus according to the invention. In this
case, a conductor track 5' in the form of a circular coil winding
is provided as a printed circuit within the attachment ring 15,
with electrical connecting component 6 being passed out of the
attachment ring 15, and being operatively connected to an
evaluation device 16.
[0034] The additional measurement apparatus 10, which is preferably
included in the area of the programming coil 27, is used to detect
the emitted signals from the transmission or programming coil 27,
and to pass them to the evaluation device 16. The result or results
can then also be included in the programming of the projectile 13
(correction). In any case, information relating to the method of
operation of the programming coil 27 can be derived.
[0035] It is self-evident that this principle may also be used for
testing the measurement coils 24, 25, although the design
complexity is undoubtedly greater here than that for testing the
programming coil 27.
[0036] The invention being thus described, it will be obvious that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be obvious to one skilled in
the art are to be included within the scope of the following
claims.
* * * * *