U.S. patent application number 12/102779 was filed with the patent office on 2010-08-05 for munition containing sub-munitions that disperse in a circular delta grid impact pattern and method therefor.
This patent application is currently assigned to LOCKHEED MARTIN CORPORATION. Invention is credited to Jyun-Horng Fu.
Application Number | 20100192796 12/102779 |
Document ID | / |
Family ID | 42341793 |
Filed Date | 2010-08-05 |
United States Patent
Application |
20100192796 |
Kind Code |
A1 |
Fu; Jyun-Horng |
August 5, 2010 |
MUNITION CONTAINING SUB-MUNITIONS THAT DISPERSE IN A CIRCULAR DELTA
GRID IMPACT PATTERN AND METHOD THEREFOR
Abstract
A method is disclosed for packaging sub-munitions within stacks
of same, in a cylindrical payload space, such that the
sub-munitions emerge into a circular delta grid pattern when
deployed.
Inventors: |
Fu; Jyun-Horng; (Linden
Creek Ct., VA) |
Correspondence
Address: |
Lockheed Martin c/o;DEMONT & BREYER, LLC
100 COMMONS WAY, Ste. 250
HOLMDEL
NJ
07733
US
|
Assignee: |
LOCKHEED MARTIN CORPORATION
Bethesda
MD
|
Family ID: |
42341793 |
Appl. No.: |
12/102779 |
Filed: |
April 14, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60911416 |
Apr 12, 2007 |
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Current U.S.
Class: |
102/489 ;
86/51 |
Current CPC
Class: |
F41H 11/12 20130101;
F42B 12/58 20130101 |
Class at
Publication: |
102/489 ;
86/51 |
International
Class: |
F42B 12/58 20060101
F42B012/58; F42B 39/00 20060101 F42B039/00 |
Claims
1. A method for packaging sub-munitions, wherein the method
comprises: providing at least one stack of sub-munitions, wherein
the stack comprises a plurality of layers of sub-munitions, wherein
the sub-munitions in each of the layers are arranged so that any
three adjacent sub-munitions within a given layer are arranged in
the form an equilateral triangle, and wherein the stack is selected
from the group consisting of a three-layer stack containing three
layers of sub-munitions and a four layer stack containing four
layers of sub-munitions; and offsetting each of the layers within
the selected stack from all other layers in the stack, wherein: (a)
when the three-layer stack is selected: (i) establishing a location
for a first of the three layers; (ii) offsetting a second of the
three layers relative to the first so that a sub-munition from the
second layer superposes a center of a first equilateral triangle
formed by three sub-munitions from the first layer; and (iii)
offsetting a third of the three layers relative to the second so
that a sub-munition from the third layer superposes a center of the
first equilateral triangle; and (b) when the four-layer stack is
selected: (i) establishing a location for a first of the four
layers; (ii) offsetting a second of the four layers relative to the
first so that a sub-munition from the second layer superposes a
midpoint of a first side of a second equilateral triangle formed by
three sub-munitions from the first layer; (iii) offsetting a third
of the four layers relative to the first so that a sub-munition
from the third layer superposes a midpoint of a second side of the
second equilateral triangle; (iv) offsetting a fourth of the four
layers relative to the first so that a sub-munition from the fourth
layer superposes a midpoint of a third side of the second
equilateral triangle.
2. The method of claim 1 wherein the total number of layers, S,
obeys the relation: S=3.sup.p.times.4.sup.q, wherein p and q are
integers and wherein 3 represents the three-layer stack and 4
represents the four-layer stack.
3. The method of claim 1 wherein when a spacing between nearest
sub-munitions in a given layer of the three-layer stack is one
unit, the impact spacing between nearest sub-munitions from the
three-layer stack is 1/(3).sup.1/2 units.
4. The method of claim 1 wherein when a spacing between nearest
sub-munitions in a given layer of the four-layer stack is one unit,
the impact spacing between nearest sub-munitions from the
four-layer stack is 1/2 units.
5. The method of claim 1 wherein the sub-munition is a counter-mine
dart.
6. A method for packaging sub-munitions, wherein the method
comprises: providing at least one stack of sub-munitions, wherein
the stack comprises a plurality of layers of sub-munitions, wherein
the sub-munitions in each of the layers are arranged so that any
three adjacent sub-munitions within a given layer are arranged in
the form an equilateral triangle, and wherein the stack is selected
from the group consisting of a three-layer stack containing three
layers of sub-munitions and a four layer stack containing four
layers of sub-munitions; and offsetting each of the layers within
the selected stack from all other layers in the stack so that: (a)
the impact spacing from the three-layer stack is 1/(3).sup.1/2
units based on a spacing of one unit between nearest sub-munitions
in a given layer of the three-layer stack; and (b) the impact
spacing from the four layer stack is 1/2 units based on a spacing
of one unit between nearest sub-munitions in a given layer of the
four-layer stack.
7. The method of claim 5 wherein the total number of layers, S,
obeys the relation: S=3.sup.p.times.4.sup.q, wherein p and q are
integers and wherein 3 represents the three-layer stack and 4
represents the four-layer stack.
8. The method of claim 6 wherein the sub-munition is a counter-mine
dart.
9. A munition comprising: a first plurality of sub-munitions,
wherein: (a) the first plurality of sub-munitions are arranged in a
second plurality of layers; (b) each layer includes a portion of
the first plurality of sub-munitions, (c) each portion includes
substantially the same number of sub-munitions; (d) sub-munitions
in each layer are arranged so that any three nearest sub-munitions
form an equilateral triangle; and (e) layers are arranged into
groups of three or four layers, but not both, and obey the relation
S=3.sup.p.times.4.sup.q, wherein p and q are integers and wherein 3
represents the three-layer stack and 4 represents the four-layer
stack.
Description
STATEMENT OF RELATED CASES
[0001] This case claims priority of U.S. Provisional Patent
Application 60/911,416, which was filed on Apr. 12, 2007 and is
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to packaging and dispensing
sub-munitions.
BACKGROUND OF THE INVENTION
[0003] Current approaches to beach and surf zone mine clearance
depend on the dispensing of large numbers of sub-munitions from a
parent munition (e.g., a missile, etc.). The mine clearance mission
requires a uniform distribution of sub-munitions, such as "darts,"
over the target area. The dispersal pattern is affected by many
factors, including the angle of attack, velocity, and rotational
rate of the parent vehicle, the aerodynamic design of the darts,
dart collision, and the different aerodynamic regimes that exist in
the vicinity of the parent munition.
[0004] It has been recognized that it is particularly effective,
for mine clearance operations, to deploy darts in a simple
geometric pattern called a circular delta grid ("CDG") pattern. In
a CDG pattern, nodes form an equilateral triangle (delta), with a
circular perimeter. In the context of mine clearance and
sub-munitions, the CDG pattern is a pattern in which the nearest
three sub-munitions form an equilateral triangle and collectively
all projectiles form a circle of tightest coverage, the radius of
which is determined by the total number of darts in the
payload.
[0005] Although the desirability of deploying the darts in a CDG
pattern is recognized, there is an issue as to how to package the
darts in a cylindrical payload space such that, when dispensed, the
"darts" emerge and impact in the CDG pattern. In fact, the problem
is complicated by the fact that typically, there will be multiple
stacks of darts within the payload space.
SUMMARY
[0006] The invention provides the solution to the packaging issue
posed above.
[0007] The illustrative embodiment of the present invention is a
packaging method. Consider a payload cylinder that receives a
number, S, of layers of projectiles, such as the counter-mine darts
disclosed in U.S. Provisional Patent Application 60,985,516, filed
Nov. 5, 2007 and incorporated by reference herein. Each layer
includes the same number, N, of projectiles.
[0008] Assume one of the layers is centered (i.e., co-axial) with
the payload cylinder. Beginning from the center of an equilateral
triangle, define three 120-degree sectors. The inventor has
determined that if N is of the form (3.sup.p.times.4.sup.Q), then
by off-setting the remaining (S-1) layers in certain ways, the
total of number of projectiles (i.e., N.times.S) generates a CDG
pattern upon dispersion.
[0009] There are two arrangements that satisfy the requirement for
the CDG pattern. One arrangement comprises three layers and the
other arrangement comprises four layers. Based on a 1-unit spacing
between adjacent projectiles in a given layer, the spacing between
adjacent projectiles over the three-layer pattern is 1/(3.sup.1/2)
units and the spacing between adjacent projectiles over the
four-layer pattern in 1/2 units. Multiple groupings of three-layer
bunches or four-layer bunches can be contained within a payload
cylinder in accordance with the formula: S=3.sup.p.times.4.sup.q,
wherein p and q are integers.
[0010] In some embodiments, delays are artificially created so that
the radial distances of the sub-munitions are as designed.
[0011] The illustrative embodiment provides what is believed to be
the only solution to this packaging/dispensing problem. The
solution also indicates how to integrate the payload geometric
configuration with other design considerations.
[0012] Recasting the illustrative embodiment of the present
invention as a dispersion pattern rather than a packaging pattern,
as in the sequential "filling into the middles," an alternative
concept of operations for mine clearance is obtained. That is, for
a target-defeat mission that employs sub-munitions, the radius of
coverage can be established at a relatively large value. The
"middle" is filled (i.e., the projectile dispersion density is
increased by increasing the number of layers of sub-munitions),
only after an attempt to hit/kill fails. This conserves the number
of payload rounds, sorties, etc., that are required. This is
feasible, of course, only if the target is not moving, as is the
case in most mine clearance operations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 depicts a side view of the payload of munition,
wherein the payload comprises a plurality of layers of
sub-munitions arranged in a stack in accordance with the
illustrative embodiment of the present invention.
[0014] FIG. 2 depicts an enlarged view of FIG. 1, showing the
arrangement of several sub-munitions within one of the layers.
[0015] FIG. 3 depicts the concept of organizing a plurality of
layers into a stack of sub-munitions.
[0016] FIG. 4 depicts the stacks of sub-munitions shown in FIG. 3
overlying one another, wherein each stack is slightly offset from
the other stacks in accordance with the present teachings.
[0017] FIGS. 5A through 5C depict the sequential stacking of three
layers of sub-munitions, wherein the spacing between nearest
sub-munitions across all three layers is 1/(3).sup.1/2 units.
[0018] FIGS. 6A through 6D depict the sequential stacking of four
layers of sub-munitions, wherein the spacing between adjacent
sub-munitions in each layer 1/2 of a unit.
[0019] FIG. 7 depicts a method in accordance with the present
invention for conducting target defeat sorties.
DETAILED DESCRIPTION
[0020] The present invention provides a way to pack sub-munitions,
such as counter-mine darts, in a parent munition such that they
when impact a target area, they do so in a circular delta grid
(CDG) pattern. Only certain packing arrangements will yield a CDG
pattern on deployment of the sub-munitions.
[0021] FIG. 1 depicts munition 100 containing a plurality of
sub-munitions 102. The sub-munitions are arranged into a plurality
of layers 104-1, 104-2, 104-3, and 104-4. Each layer is separated
from one another, and the sub-munitions therein are contained, by
separators 106. The separators can provide an adjustable delay
between successive layers of munitions, such as by changing the
thickness of the separators.
[0022] FIG. 2 depicts several of sub-munitions 102 from a given
layer packed in such a manner that any three nearest sub-munitions
fall on the vertices of equilateral triangle 210.
[0023] FIGS. 3 and 4 depict, figuratively, the stacking of four
layers 104-1, 104-2, 104-3, and 104-4 of sub-munitions. Each
sub-munition 102 in each layer falls on the vertex of equilateral
triangle 210, as per FIG. 2. FIG. 4 depicts the offsetting of each
layer relative to the other layers to develop a CDG pattern on
dispersal.
[0024] As in indicated in the Summary section, layers can be
stacked only in groups of three or four to achieve a CDG pattern on
dispersal. FIGS. 5A through 5C depict the three-layer grouping of
sub-munitions. The arrangement of munitions within each layer is
identical; they all fall on the vertices of an equilateral triangle
of unit size. But, as is apparent from the FIGS. 5A-5C, the layers
are offset from one another in a particular way.
[0025] FIG. 5A depicts a first layer of sub-munitions, wherein a
sub-munition is assumed to present at all vertices. An illustrative
grouping is depicted in FIG. 5A, wherein the "1" that appears at
the three vertices is meant to signify that these vertices are
occupied by a munition from layer-1.
[0026] FIG. 5B depicts a second layer of sub-munitions slightly
offset from the first layer. In particular, a vertex (sub-munition)
is positioned to be in the center of equilateral triangle formed by
layer-1 sub-munitions. The illustrative grouping representative of
the munitions from the first layer as shown in FIG. 5A is
reproduced in the same location in FIG. 5B for reference. Using
only two layers would not result in a CDG impact pattern; for that,
an additional layer must be added for the offset selected.
[0027] FIG. 5C depicts a third layer of sub-munitions offset from
the second layer in the same manner as the second layer is offset
from the first layer. That is, a vertex from a layer-3 triangular
grouping falls in the center of a layer-2 triangular grouping. The
illustrative groupings for layers one and two that were shown in
FIG. 5B are reproduced in FIG. 5C in the same location for
reference. Note that the scale changes across the three Figures to
resolve the amount of the offset between the three layers.
[0028] Assuming a unit distance between adjacent sub-munitions in
any given layer, the three-layer stack provides a distance of
1/(3.sup.1/2) units. In other words, if the unit spacing is 1 meter
between adjacent sub-munitions in any given layer, the spacing
between adjacent sub-munitions in the impact grid (assuming no
dispersal) is about 0.58 meters. The spacing between sub-munitions
at impact (assuming no dispersal) is referred to in this
description and the appended claims as "impact spacing."
[0029] FIGS. 6A through 6D depict the four-layer grouping of
sub-munitions in accordance with the present invention. The layers
in the four-layer grouping are offset in a different manner than in
the three-layer grouping.
[0030] FIG. 6A depicts a first layer of sub-munitions, wherein a
sub-munition is assumed to present at all vertices. An illustrative
grouping is depicted in FIG. 6A, wherein the "1" that appears at
the three vertices is meant to signify that these vertices are
occupied by a munition from layer 1.
[0031] FIG. 6B depicts a second layer that is slightly offset from
the first layer. In particular, layer-2 is offset by positioning a
vertex (sub-munition) at the mid-point of one of the sides of an
equilateral triangular grouping formed in layer-1. The locations of
several representative munitions from the two layers are identified
(by the numerals "1" and "2") to highlight their relative
positions. Reference to this Figure shows that after two layers, a
CDG pattern has not developed. That is, all nearest neighbors do
not fall on vertices of an equilateral triangle. The notation for
one of the layer-1 munitions is omitted to make it easier to
recognize the unit size equilateral triangular arrangement of
layer-2 munitions.
[0032] FIG. 6C depicts the third layer slightly offset from layers
1 and 2 by positioning a vertex (sub-munition) at the mid-point of
one of the other sides of an equilateral triangular grouping formed
in layer-1. Reference to FIG. 6C shows the now each layer-1
triangular arrangement has a layer-2 munition superposed at the
midpoint between one of its sides and a layer-3 munition that is
superposed at the midpoint between a second of its sides. It is
clear that there is a "gap" that remains; that is, an additional
munition must be superposed at the midpoint of the third side of
the triangular to complete the CDG pattern. This is done by adding
a fourth layer. The notations for one of the layer-1 sub-munitions
and one of the layer-2 sub-munitions are omitted to make it easier
to recognize the unit size equilateral triangular arrangement of
layer-3 munitions.
[0033] FIG. 6D depicts the fourth layer slightly offset from layers
1-3 by superposing a vertex (sub-munition) at the midpoint of the
third and final side of a layer-1 triangular arrangement. As is
clear from FIG. 6D, the superposition of these four layers fills
the pattern to create the desired CDG arrangement. Again, the
identifier for a representative sub-munition from each of the
layers 1-3 is omitted to illustrate the unit size equilateral
triangular arrangement of layer-4 munitions.
[0034] Thus, FIGS. 5A through 5C depict the manner in which a
three-layer stack is arranged to create a CDG impact pattern.
Likewise, FIGS. 6A through 6D depict the manner in which a
four-layer stack is arranged to create a CDG impact pattern. When
more than a single layer of sub-munitions are required (for
coverage, etc.), only three-layer "stacks" and four-layer "stacks,"
arranged as shown, will create the desired CDG impact pattern.
[0035] Notwithstanding the fact that one "three-layer" stack or one
"four-layer" stack of sub-munitions will provide the desired CDG
pattern, two such stacks will not. In fact, the inventor has
discovered that to yield the desired impact pattern, the number of
layers of sub-munitions within a canister must obey the
relation:
S=3.sup.p.times.4.sup.q, wherein p and q are integers [1]
[0036] Canisters must include either three-layer stacks or
four-layer stacks. The "3" in expression [1] refers to three-layer
stacks and the "4" refers to four-layer stacks. So, if a munitions
canister includes three-layer stacks, then q=0, so that
S=3.sup.p.times.1. Likewise, if a munitions canister includes
four-layer stacks, then p=0, so that S=1.times.4.sup.q.
[0037] The allowed arrangements can therefore be viewed as being
"recursive." That is, allowed arrangements (i.e., permissible total
number of layers) for three-layer stacks are:
3.sup.p=3 (p=1), which is one, three-layer stack;
3.sup.p=9 (p=2), which is three, three-layer stacks;
3.sup.p=27 (p=3), which is nine (3.times.3), three-layer stacks;
and so forth.
Similarly, the allowed arrangements for four-layer stacks are:
4.sup.q=4 (q=1), which is one, four-layer stack;
4.sup.q=16 (q=2), which is four, four-layer stacks;
4.sup.q=64 (q=3), which is sixteen (4.times.4), four-layer stacks;
and so forth.
[0038] The packaging approach described above leads to a
methodology for mine clearance, embodied as method 700 depicted in
FIG. 7.
[0039] In accordance with operation 702 of the method, the spacing
between adjacent sub-munitions (in a layer) is selected. A sortie
is conducted, as per operation 704, and a "battle damage
assessment" or BDA is performed in operation 706.
[0040] If there are no further targets, then the method terminates
at operation 714. If, on the other hand, targets remain, a decision
is made as to whether the munitions coverage should be altered
based on the BDA. If the BDA indicates that coverage is acceptable,
then a subsequent sortie is then conducted.
[0041] If the BDA indicates that coverage is unacceptable, a
decision is made, in accordance with operation 712, to increase the
density of coverage. This can be done by decreasing the spacing
between sub-munitions (if possible) or, alternatively, by
increasing the layers of sub-munitions in the parent munition in
accordance with the packaging methodology previously presented.
After altering the packaging density, a subsequent sortie is
conducted.
[0042] It is to be understood that the disclosure teaches just one
example of the illustrative embodiment and that many variations of
the invention can easily be devised by those skilled in the art
after reading this disclosure and that the scope of the present
invention is to be determined by the following claims.
* * * * *