U.S. patent application number 15/759275 was filed with the patent office on 2018-06-28 for system, method and computer program for timing interceptor missile warhead initiation.
This patent application is currently assigned to ISRAEL AEROSPACE INDUSTRIES LTD.. The applicant listed for this patent is ISRAEL AEROSPACE INDUSTRIES LTD.. Invention is credited to Pavel BRUK, Menachem CHAIMOVITZ, Allan C. KAHANE, Shai VAINGAST.
Application Number | 20180180385 15/759275 |
Document ID | / |
Family ID | 58288225 |
Filed Date | 2018-06-28 |
United States Patent
Application |
20180180385 |
Kind Code |
A1 |
KAHANE; Allan C. ; et
al. |
June 28, 2018 |
SYSTEM, METHOD AND COMPUTER PROGRAM FOR TIMING INTERCEPTOR MISSILE
WARHEAD INITIATION
Abstract
An interceptor missile comprising: a warhead; a processing unit;
one or more sensors configured to obtain at least one reading
enabling determination of a passing direction of the interceptor
missile with respect to a target; wherein the processing unit is
configured to: receive the reading from the sensors; determine a
passing direction utilizing the reading; and obtain a required time
T.sub.go for initiating the warhead, utilizing the determined
passing direction.
Inventors: |
KAHANE; Allan C.; (Rehovot,
IL) ; CHAIMOVITZ; Menachem; (Kefar Sava, IL) ;
BRUK; Pavel; (Modi'in-Maccabim-Re'ut, IL) ; VAINGAST;
Shai; (Ganei Tikva, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ISRAEL AEROSPACE INDUSTRIES LTD. |
Lord |
|
IL |
|
|
Assignee: |
ISRAEL AEROSPACE INDUSTRIES
LTD.
Lod
IL
|
Family ID: |
58288225 |
Appl. No.: |
15/759275 |
Filed: |
September 12, 2016 |
PCT Filed: |
September 12, 2016 |
PCT NO: |
PCT/IL2016/051016 |
371 Date: |
March 12, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F42B 15/10 20130101;
F41H 11/02 20130101; F41G 7/20 20130101 |
International
Class: |
F41G 7/20 20060101
F41G007/20; F41H 11/02 20060101 F41H011/02; F42B 15/10 20060101
F42B015/10 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 17, 2015 |
IL |
241677 |
Claims
1. An interceptor missile comprising: a warhead; a processing unit;
one or more sensors configured to obtain at least one reading
enabling determination of a passing direction of the interceptor
missile with respect to a target; wherein the processing unit is
configured to: receive the reading from the sensors; determine a
passing direction utilizing the reading; and obtain a required time
T.sub.go for initiating the warhead, utilizing the determined
passing direction.
2. The interceptor missile of claim 1 wherein the reading enables
determination of a range and a range rate of the interceptor
missile with respect to the target and wherein the processing unit
is further configured to obtain the range and the range rate from
the readings and initiate the warhead when T.sub.go is
substantially equal to, or smaller then, the range multiplied by
the range rate and divided by a power of two of a closing velocity
of the interceptor.
3. The interceptor missile of claim 2 wherein T.sub.go is obtained
utilizing target information indicative of a target type.
4. The interceptor missile of claim 2 wherein T.sub.go is a default
value when the target type is unknown.
5. The interceptor missile of claim 1 wherein the initiation time
is determined such that the number of fragments of the interceptor
expected to hit the target is optimal.
6. The interceptor missile of claim 1 wherein the initiation time
is determined such that the number of fragments of the interceptor
expected to hit a selected part of the target is optimal.
7. The interceptor missile of claim 6 wherein the selected part is
the front of the target or the rear of the target.
8. The interceptor missile of claim 1 wherein the required time
T.sub.go in case the passing direction is indicative of a
tail-passing scenario, wherein the interceptor trajectory passes
above the target, is different than the required time T.sub.go in
case the passing direction is indicative of a head-passing
scenario, wherein the interceptor trajectory passes below the
target.
9. The interceptor missile of claim 1 wherein the sensors are
proximity sensors.
10. The interceptor of claim 9 wherein the proximity sensors are
proximity fuses.
11. The interceptor missile of claim 9 wherein the passing
direction is determined also utilizing information relating to the
location of the proximity sensors on the interceptor missile, and
information of the interceptor missile roll angle and attack
angle.
12. The interceptor missile of claim 1 wherein the warhead is
omni-directional.
13. An interceptor missile comprising a warhead and a processing
unit, the processing unit configured to determine an initiation
time of the warhead based on a passing direction, the passing
direction being indicative of a tail passing, wherein the
interceptor trajectory passes above the target, or a head passing,
wherein the interceptor trajectory passes below the target.
14. An interceptor missile comprising a warhead and a processing
unit, the processing unit is configured to: provide data
representative of at least two warhead initiation times, each
corresponding to a distinct passing scenario associated with a
passing direction; calculate an interception passing direction
based on data received from one or more sensors of the interceptor;
initiate the warhead at an initiation time substantially equal to
the warhead initiation time corresponding to the interception
passing direction.
15. A method for timing initiation of a warhead of an interceptor
missile, the method comprising: receiving, by a processing unit,
readings from one or more sensors configured to obtain at least one
reading enabling determination of a passing direction of the
interceptor missile with respect to a target; determining a passing
direction utilizing the readings; and obtaining a required time
T.sub.go for initiating the warhead, utilizing the determined
passing direction.
16. The method of claim 15 wherein the reading enables
determination of a range and a range rate of the interceptor
missile with respect to the target and wherein the method further
comprising obtaining the range and the range rate from the readings
and initiating the warhead when T.sub.go is substantially equal to,
or smaller then, the range multiplied by the range rate and divided
by a power of two of a closing velocity of the interceptor missile
with respect to the target.
17. The method of claim 16 wherein T.sub.go is obtained utilizing
target information indicative of a target type.
18. The method of claim 16 wherein T.sub.go is a default value when
the target type is unknown.
19. The method of claim 15 wherein the initiation time is
determined such that the number of fragments of the interceptor
expected to hit the target is optimal.
20. The method of claim 15 wherein the initiation time is
determined such that the number of fragments of the interceptor
expected to hit a selected part of the target is optimal.
21. The method of claim 20 wherein the selected part is the front
of the target or the rear of the target.
22. The method of claim 15 wherein the required time T.sub.go in
case the passing direction is indicative of a tail-passing
scenario, wherein the interceptor trajectory passes above the
target, is different than the required time T.sub.go in case the
passing direction is indicative of a head-passing scenario, wherein
the interceptor trajectory passes below the target.
23. The method of claim 15 wherein the sensors are proximity
sensors.
24. The method of claim 23 wherein the proximity sensors are
proximity fuses.
25. The method of claim 23 wherein the passing direction is
determined also utilizing information relating to the location of
the proximity sensors on the interceptor missile, and information
of the interceptor missile roll angle and attack angle.
26. The method of claim 15 wherein the warhead is
omni-directional.
27. A method for timing initiation of a warhead of an interceptor
missile, the method comprising determining an initiation time of
the warhead based on a passing direction, the passing direction
being indicative of a tail passing, wherein the interceptor
trajectory passes above the target, or a head passing, wherein the
interceptor trajectory passes below the target.
28. A method for timing initiation of a warhead of an interceptor
missile, the method comprising: providing data representative of at
least two warhead initiation times, each corresponding to a
distinct passing scenario associated with a passing direction;
calculating, by a processing unit, an interception passing
direction based on data received from one or more sensors of the
interceptor; and initiating the warhead at an initiation time
substantially equal to the warhead initiation time corresponding to
the interception passing direction.
29. A computer program comprising computer program code means for
performing the following steps when said program is run on a
computer: receiving readings from one or more sensors configured to
obtain at least one reading enabling determination of a passing
direction of the interceptor missile with respect to a target;
determining a passing direction utilizing the readings; and
obtaining a required time T.sub.go for initiating the warhead,
utilizing the determined passing direction.
30. A computer program comprising computer program code means for
performing the following steps when said program is run on a
computer: determining an initiation time of the warhead based on a
passing direction, the passing direction being indicative of a tail
passing, wherein the interceptor trajectory passes above the
target, or a head passing, wherein the interceptor trajectory
passes below the target.
31. A computer program comprising computer program code means for
performing the following steps when said program is run on a
computer: providing data representative of at least two warhead
initiation times, each corresponding to a distinct passing scenario
associated with a passing direction; calculating an interception
passing direction based on data received from one or more sensors
of the interceptor; and initiating the warhead at an initiation
time substantially equal to the warhead initiation time
corresponding to the interception passing direction.
Description
TECHNICAL FIELD
[0001] The disclosure relates to a system and method for timing
interceptor missile warhead initiation.
BACKGROUND
[0002] When an interceptor missile is launched towards a target,
the missile is set to initiate its warhead at a certain
point-in-time T.sub.go. T.sub.go can be calculated using various
known techniques and methods. However, these techniques and methods
do not consider a passing direction of the warhead with respect to
the target. There can be at least two passing direction scenarios:
(a) tail passing, in which the interceptor passes the target at the
aft (the interceptor missile's trajectory passes above the target),
and (b) head passing, in which the interceptor passes the target at
the nose (the interceptor missile's trajectory passes below the
target). As detailed herein, considering the passing direction of
the interceptor missile with respect to the target while
determining the initiation time of the interceptor's warhead
(t.sub.go) can increase the lethality of the interceptor missile
and increase the likelihood of destroying the target.
[0003] There is thus a need in the art for a new system and method
for timing interceptor missile warhead initiation.
SUMMARY
[0004] In one aspect, in accordance with the disclosed subject
matter there is provided an interceptor missile comprising: a
warhead; a processing unit; one or more sensors configured to
obtain at least one reading enabling determination of a passing
direction the interceptor missile with respect to a target; wherein
the processing unit is configured to: receive the reading from the
sensors; determine a passing direction utilizing the readings; and
obtain a required time T.sub.go for initiating the warhead,
utilizing the determined passing direction.
[0005] In some cases, the reading enables determination of a range
and a range rate of the interceptor missile with respect to the
target and the processing unit is further configured to obtain the
range and the range rate from the readings and initiate the warhead
when T.sub.go is substantially equal to, or smaller then, the range
multiplied by the range rate and divided by a power of two of a
closing velocity of the interceptor with respect to the target.
[0006] In some cases, T.sub.go is obtained utilizing target
information indicative of a target type.
[0007] In some cases, T.sub.go is a default value when the target
type is unknown.
[0008] In some cases, the initiation time is determined such that
the number of fragments of the interceptor expected to hit the
target is optimal.
[0009] In some cases, the initiation time is determined such that
the number of fragments of the interceptor expected to hit a
selected part of the target is optimal.
[0010] In some cases, the selected part is the front of the target
or the rear of the target.
[0011] In some cases, the required time T.sub.go in case the
passing direction is indicative of a tail-passing scenario, wherein
the interceptor trajectory passes above the target, is different
than the required time T.sub.go in case the passing direction is
indicative of a head-passing scenario, wherein the interceptor
trajectory passes below the target.
[0012] In some cases, the sensors are proximity sensors.
[0013] In some cases, the proximity sensors are proximity
fuses.
[0014] In some cases, the passing direction is determined also
utilizing information relating to the location of the proximity
sensors on the interceptor missile, and information of the
interceptor missile roll angle and attack angle.
[0015] In some cases, the warhead is omni-directional.
[0016] In another aspect, in accordance with the disclosed subject
matter there is provided an interceptor missile comprising a
warhead and a processing unit, the processing unit configured to
determine an initiation time of the warhead based on a passing
direction, the passing direction being indicative of a tail
passing, wherein the interceptor trajectory passes above the
target, or a head passing, wherein the interceptor trajectory
passes below the target.
[0017] In another aspect, in accordance with the disclosed subject
matter there is provided an interceptor missile comprising a
warhead and a processing unit, the processing unit is configured
to: provide data representative of at least two warhead initiation
times, each corresponding to a distinct passing scenario associated
with a passing direction; calculate an interception passing
direction based on data received from one or more sensors of the
interceptor; initiate the warhead at an initiation time
substantially equal to the warhead initiation time corresponding to
the interception passing direction.
[0018] In another aspect, in accordance with the disclosed subject
matter there is provided a method for timing initiation of a
warhead of an interceptor missile, the method comprising:
receiving, by a processing unit, readings from one or more sensors
configured to obtain at least one reading enabling determination of
a passing direction of the interceptor missile with respect to a
target; determining a passing direction utilizing the readings; and
obtaining a required time T.sub.go for initiating the warhead,
utilizing the determined passing direction.
[0019] In some cases, the reading enables determination of a range
and a range rate of the interceptor missile with respect to the
target and the method further comprises obtaining the range and the
range rate from the readings and initiating the warhead when
T.sub.go is substantially equal to, or smaller then, the range
multiplied by the range rate and divided by a power of two of a
closing velocity of the interceptor missile with respect to the
target.
[0020] In some cases, T.sub.go is obtained utilizing target
information indicative of a target type.
[0021] In some cases, T.sub.go is a default value when the target
type is unknown.
[0022] In some cases, the initiation time is determined such that
the number of fragments of the interceptor expected to hit the
target is optimal.
[0023] In some cases, the initiation time is determined such that
the number of fragments of the interceptor expected to hit a
selected part of the target is optimal.
[0024] In some cases, the selected part is the front of the target
or the rear of the target.
[0025] In some cases, the required time Tgo in case the passing
direction is indicative of a tail-passing scenario, wherein the
interceptor trajectory passes above the target, is different than
the required time Tgo in case the passing direction is indicative
of a head-passing scenario, wherein the interceptor trajectory
passes below the target.
[0026] In some cases, the sensors are proximity sensors.
[0027] In some cases, the proximity sensors are proximity
fuses.
[0028] In some cases, the passing direction is determined also
utilizing information relating to the location of the proximity
sensors on the interceptor missile, and information of the
interceptor missile roll angle and attack angle.
[0029] In some cases, the warhead is omni-directional.
[0030] In another aspect, in accordance with the disclosed subject
matter there is provided a method for timing initiation of a
warhead of an interceptor missile, the method comprising
determining an initiation time of the warhead based on a passing
direction, the passing direction being indicative of a tail
passing, wherein the interceptor trajectory passes above the
target, or a head passing, wherein the interceptor trajectory
passes below the target.
[0031] In another aspect, in accordance with the disclosed subject
matter there is provided a method for timing initiation of a
warhead of an interceptor missile, the method comprising: providing
data representative of at least two warhead initiation times, each
corresponding to a distinct passing scenario associated with a
passing direction; calculating, by a processing unit, an
interception passing direction based on data received from one or
more sensors of the interceptor; and initiating the warhead at an
initiation time substantially equal to the warhead initiation time
corresponding to the interception passing direction.
[0032] In another aspect, in accordance with the disclosed subject
matter there is provided a computer program comprising computer
program code means for performing the following steps when said
program is run on a computer: receiving readings from one or more
sensors configured to obtain at least one reading enabling
determination of a passing direction of the interceptor missile
with respect to a target; determining a passing direction utilizing
the reading; and obtaining a required time T.sub.go for initiating
the warhead, utilizing the determined passing direction.
[0033] In another aspect, in accordance with the disclosed subject
matter there is provided a computer program comprising computer
program code means for performing the following steps when said
program is run on a computer: determining an initiation time of the
warhead based on a passing direction, the passing direction being
indicative of a tail passing, wherein the interceptor trajectory
passes above the target, or a head passing, wherein the interceptor
trajectory passes below the target.
[0034] In another aspect, in accordance with the disclosed subject
matter there is provided a computer program comprising computer
program code means for performing the following steps when said
program is run on a computer: providing data representative of at
least two warhead initiation times, each corresponding to a
distinct passing scenario associated with a passing direction;
calculating an interception passing direction based on data
received from one or more sensors of the interceptor; and
initiating the warhead at an initiation time substantially equal to
the warhead initiation time corresponding to the interception
passing direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] In order to understand the subject matter and to see how it
may be carried out in practice, examples will be described, with
reference to the accompanying drawings, in which:
[0036] FIG. 1 is an illustration of an exemplary interceptor
missile, in accordance with the presently disclosed subject
matter;
[0037] FIG. 2 is a block diagram illustrating an example of an
interceptor missile mission computer, in accordance with the
presently disclosed subject matter;
[0038] FIGS. 3a and 3b are illustrations of exemplary passing
scenarios, in accordance with the presently disclosed subject
matter;
[0039] FIG. 4 is an illustration of the number of fragments
expected to hit the target depending on the initiation time of the
warhead in two exemplary passing direction scenarios, in accordance
with the presently disclosed subject matter;
[0040] FIG. 5 is a flowchart illustrating an exemplary interception
process, in accordance with the presently disclosed subject matter;
and
[0041] FIG. 6 is an illustration of the calculation of time to
T.sub.0, in accordance with the presently disclosed subject
matter.
DETAILED DESCRIPTION OF THE INVENTION
[0042] In the following detailed description, numerous specific
details are set forth in order to provide a thorough understanding
of the subject matter. However, it will be understood by those
skilled in the art that some examples of the subject matter may be
practiced with these specific details. In other instances, well
known methods, procedures and components have not been described in
detail so as not to obscure the description.
[0043] As used herein, and unless explicitly stated otherwise, the
term "memory" refers to any module for storing data for the short
and/or long term, locally and/or remotely. Examples of memory may
include inter-alia: any type of disk including floppy disk, hard
disk, optical disk, CD-ROMs, magnetic-optical disk, magnetic tape,
flash memory, random access memory (RAM), dynamic random access
memory (DRAM), static random access memory (SRAM), read-only memory
(ROM), programmable read only memory (PROM), electrically
programmable read-only memory (EPROM), electrically erasable and
programmable read-only memory (EEPROM), magnetic card, optical
card, any other type of media suitable for storing electronic
instructions and capable of being coupled to a system bus, and/or a
combination of any of the above.
[0044] Usage in the specification of the term "for example", "such
as", "for instance", "e.g.", "say", "possibly", "optionally" "one
example", "illustrated example", "some examples", "another
example", "other examples", "some other examples", "various
examples", "one instance", "some instances", "another instance",
"other instances", "some other instances", "various instances",
"one case", "some cases", "another case", "other cases", "some
other cases", "various cases", or variants thereof means that a
particular described feature, structure or characteristic is
included in at least one non-limiting example of the subject
matter, but not necessarily in all examples. The appearance of the
same term does not necessarily refer to the same example.
[0045] The term "illustrated example" is used to direct the
attention of the reader to one or more of the figures, but it
should not be construed as necessarily favoring any example over
any other.
[0046] It should be appreciated that certain features, structures
and/or characteristics disclosed herein, which are, for clarity,
described in the context of separate examples, may be provided in
combination in a single example. Conversely, various features,
structures and/or characteristics disclosed herein, which are for
brevity, described in the context of a single example, may also be
provided separately or in any suitable sub-combination.
[0047] Unless specifically stated otherwise, as apparent from the
following discussions, it is appreciated that throughout the
specification, discussions utilizing terms such as "receiving",
"obtaining", "determining", "initiating", "providing",
"calculating" or the like, refer to the action(s) and/or
process(es) of any combination of software, hardware and/or
firmware. For example, these terms may refer in some cases to the
action(s) and/or process(es) of a machine such as a computer, that
manipulates and/or transforms data into other data, the data
represented as physical, such as electronic quantities, and/or the
data representing physical objects.
[0048] Referring now to the Figures, FIG. 1 is an illustration of
an exemplary interceptor missile, in accordance with the presently
disclosed subject matter.
[0049] The Interceptor missile 100 in accordance with the presently
disclosed subject matter can be any interceptor missile having a
warhead, including an air-to-air interceptor missile, a
surface-to-air interceptor missile, or any other type of
interceptor missile having a warhead.
[0050] The interceptor missile 100 comprises a warhead 120, which,
when activated, can result in fragments of the interceptor missile
100 being sprayed in a certain direction (in case the warhead 120
is designed in this manner) or in all directions (in case the
warhead 120 is omni-directional).
[0051] In some cases, the interceptor missile 100 further comprises
one or more sensors (and in more specific cases two or more
sensors) configured to obtain one or more readings indicative of a
spatial relativity between the interceptor missile 100 and a target
(not shown). The readings can include the range and the range rate
between the interceptor missile and a target, which can be obtained
from the readings (in some cases the readings can include data
enabling determination of the range and the range rate and in such
cases the range and range rate can be determined utilizing such
data).
[0052] The readings obtained by the sensors can enable
determination of a passing direction, as indicated herein. It is to
be noted that in some cases the sensors can be external to the
interceptor missile 100 (e.g. they can be located on external
platforms, including airborne platforms, ground platforms,
etc.).
[0053] The passing direction can be indicative of a
passing-direction scenario, e.g. a tail-passing scenario, wherein
the interceptor missile's 100 trajectory passes above the target,
or a head-passing scenario, wherein the interceptor missile's 100
trajectory passes below the target. It is to be noted that in some
cases additional and/or alternative passing-direction scenarios can
exist.
[0054] In one particular example, the sensor can be a proximity
sensor (e.g. a proximity fuse), having at least two antennas--an
upper antenna 150 and a lower antenna 160. The antennas can be
positioned in a manner that enables determination of a passing
direction of the interceptor missile 100 with respect to a target
(utilizing the information relating to the location of the
proximity sensors on the interceptor missile, and the interceptor
missile roll angle). For example, the antennas can be positioned on
substantially opposite sides of the interceptor missile 100--the
upper antenna 150 substantially on the upper side of the
interceptor missile 100 and the lower antenna 160 substantially on
the lower side of the interceptor missile 100. Such positioning of
the antennas results in coverage of a first area by the upper
antenna 150 and a second area by the lower antenna 160. It is to be
noted that in some cases, in order to determine which antenna is
the lower antenna 160 and which antenna is the upper antenna 150,
information about the interceptor missile's 100 roll angle is
required and can be obtained using known methods and/or
techniques.
[0055] In the case of utilizing a proximity sensor, determining
which antenna sensed the target (e.g. the lower antenna 160 or the
upper antenna 150) can enable determination of the passing
direction of the interceptor missile 100 with respect to the
target, for example by determining which antenna (e.g. the lower
antenna 160 or the upper antenna 150) sensed/senses the target in
the area covered thereby. In some cases, if the lower antenna 160
sensed the target, the interception scenario is a tail passing
scenario, whereas if the upper antenna 150 sensed the target, the
interception scenario is a head passing scenario.
[0056] In some cases, if a certain antenna sensed the target during
a certain part of the interception process and another antenna
sensed the target during another part of the interception process,
the time of sensing can be taken into account and a series of
readings received from the sensors can be utilized for determining
the evolution of the interception scenario and the corresponding
passing scenario.
[0057] It is to be noted that in the example provided above only
two antennas are used, however a larger number of antennas can be
used as well (e.g. distributed in a known manner on the interceptor
missile 100). It is to be further noted that other types of sensors
can be used, such as a radar, an electro-optical sensor, etc., as
long as the data acquired by the sensors enables determination of a
passing direction scenario (tail-passing or head-passing), and a
range and a range rate between the interceptor missile and a
target. In addition, in some cases more than one sensor and/or
sensor type can be used for this purpose.
[0058] In accordance with the presently disclosed subject matter,
the one or more sensors are connected (e.g. via a wired or wireless
connection) to a mission computer 110, as further detailed herein
with respect to FIG. 2, Attention to which is now drawn.
[0059] FIG. 2 is a block diagram illustrating an example of an
interceptor missile mission computer, in accordance with the
presently disclosed subject matter.
[0060] In some cases, mission computer 110 can be connected to one
or more sensors 240 in any manner that enables mission computer 110
(or any component thereof) to receive at least one readings
acquired by the one or more sensors 240 including a range and a
range rate (or data enabling determination thereof) between the
interceptor missile and a target.
[0061] Mission computer 110 further comprises a processing unit
200. Processing unit 200 comprises, or is otherwise associated
with, at least one processor (e.g. digital signal processor (DSP),
microcontroller, field programmable gate array (FPGA), application
specific circuit (ASIC), etc.) configured to manage and control
different components of mission computer 110 and carry out the
relevant operations.
[0062] Processing unit 200 can comprise a passing direction
determination module 220 and an initiation time determination
module 230. Processing unit can still further comprise, or be
otherwise associated with, a data repository 210.
[0063] According to some embodiments of the presently disclosed
subject matter, passing direction determination module 220 can be
configured to obtain readings acquired by the one or more sensors
240 for determining a passing direction. The passing direction can
be indicative of a passing-direction scenario, e.g. a tail-passing
scenario, wherein the interceptor missile's 100 trajectory passes
above the target, or a head-passing scenario, wherein the
interceptor missile's 100 trajectory passes below the target. It is
to be noted that in some cases additional and/or alternative
passing-direction scenarios can exist.
[0064] In some cases, initiation time determination module 230 can
be configured to determine the initiation time of the interceptor
missile's 100 warhead 120, as further detailed herein, inter alia
with respect to FIGS. 5 and 6.
[0065] Data repository 210 can be configured to store, and enable
retrieval of, data indicative of various warhead initiation times
(T.sub.go), depending on one or more of: a target type, a passing
direction, a selected part of the target to be hit, etc., as
further detailed herein, inter alia with respect to FIG. 5. Data
repository can be part of the mission computer 110, or it can be
otherwise operatively connected thereto.
[0066] Turning to FIGS. 3a and 3b, there are shown illustrations of
exemplary passing scenarios, in accordance with the presently
disclosed subject matter.
[0067] In FIG. 3a, a head passing scenario is depicted. In such
scenario, the interceptor trajectory 310 of the interceptor missile
100 passes below target 320. In order for the warhead fragments to
hit the target 320 in such head passing scenario, the warhead
initiation should be timed to a certain point in time, Tgo 340, so
that the fragments velocity vector 330 will cause the fragments of
the interceptor missile 100 to hit the target 320 in a successful
manner (e.g. in a manner that will result in destruction of the
target 320 or otherwise damaging the target so that it is unable to
achieve its mission). It can be appreciated that the fragments
velocity vector 330 is derived of the interceptor velocity
direction (in the drawing it is aligned with the interceptor
trajectory 310) and the warhead fragments velocity vector 330 (e.g.
a vector addition thereof). It can be further appreciated that most
targets have a larger length then width so that the surface area of
the target 320 the warhead fragments are required to hit in a head
passing scenario (where the fragments trajectory is substantially
lateral to the target) is smaller than the surface area in a tail
passing scenario (where the fragments trajectory is substantially
perpendicular to the target, as can be seen in FIG. 3b). This
results in head passing scenarios being more sensitive to
variations in timing of the interceptor missile's 100 warhead in
comparison to tail passing scenarios as described with reference to
FIG. 3b.
[0068] In FIG. 3b, a tail passing scenario is depicted. In such
scenario, the interceptor trajectory 310 of the interceptor missile
100 passes above target 320. In order for the warhead fragments to
hit the target 320 in such tail passing scenario, the warhead
initiation should be timed to a certain point in time, Tgo 340, so
that the fragments velocity vector 330 will cause the fragments of
the interceptor missile 100 to hit the target 320 in a successful
manner (e.g. in a manner that will result in destruction of the
target 320 or otherwise damaging the target so that it is unable to
achieve its mission). It can be appreciated that the fragments
velocity vector 330 is derived of the interceptor velocity
direction (in the drawing it is aligned with the interceptor
trajectory 310) and the warhead fragments velocity vector 330 (e.g.
a vector addition thereof). It can be further appreciated that most
targets have a larger length then width so that the surface area of
the target 320 the warhead fragments are required to hit in a tail
passing scenario (where the fragments trajectory is substantially
perpendicular to the target) is larger than the surface area in a
head passing scenario (where the fragments trajectory is
substantially lateral to the target, as can be seen in FIG. 3a).
This results in tail passing scenarios being less sensitive to
variations in timing of the interceptor missile's 100 warhead in
comparison to head passing scenarios as described with reference to
FIG. 3a.
[0069] FIG. 4 is an illustration of the number of fragments
expected to hit the target depending on the initiation time of the
warhead, in two exemplary passing direction scenarios, in
accordance with the presently disclosed subject matter.
[0070] As indicated herein, the initiation time of the interceptor
missile's 100 warhead (Tgo) has a direct effect on the number of
fragments expected to hit the target in each passing scenario.
Looking at the graph shown in FIG. 4, the vertical axis represents
the number of fragments expected to hit the target (# fragments
404) and the horizontal axis represents the initiation time of the
interceptor missile's 100 warhead (Tgo 402). Two curves appear in
the graph, one representing an exemplary head passing scenario 410
and the other representing an exemplary tail passing scenario 420.
The peak of each curve represents the maximal number of fragments
expected to hit the target at the respective passing scenario and
each such peak is associated with a corresponding Tgo.
[0071] Looking at the curve that represents an exemplary head
passing scenario 410, it can be appreciated that it has a peak at
the point marked "optimal initiation time head passing 430" (i.e.
when Tgo equals optimal initiation time head passing 430). Looking
at the curve that represents an exemplary tail passing scenario
420, it can be appreciated that it has a peak at the point marked
"optimal initiation time tail passing 440" (i.e. when Tgo equals
optimal initiation time tail passing 440). It can be appreciated
that optimal initiation time head passing 430 is different than
optimal initiation time tail passing 440.
[0072] Assuming that a certain minimal number of fragments are
required to hit the target (e.g. for destroying it or otherwise
damaging it so that it is unable to 30 achieve its mission) is
provided, e.g. as indicated by min # fragments 450 in the
illustrated graph, it can be appreciated that at least in some
cases (as shown in the illustrated example) initiating the
interceptor missile's 100 warhead 120 at optimal initiation time
tail passing 440 when in fact the passing scenario is head passing,
can result in a lower number of fragments (e.g. in comparison to
the minimal number of fragments 450) will hit the target, thus
potentially failing the interception. In a similar manner,
initiating the interceptor missile's 100 warhead 120 at optimal
initiation time head passing 430 when in fact the passing scenario
is tail passing, can result in a lower number of fragments (e.g. in
comparison to the minimal number of fragments 450) hitting the
target, thus potentially failing the interception.
[0073] It can also be appreciated when looking at the illustrated
example and as indicated above, that the time sensitivity for
initiating the warhead 102 in a tail passing scenario is lower than
the time sensitivity for initiating the warhead in a head passing
scenario. Looking at the graph, it can be appreciated that the time
range for initiating the warhead 102 for a successful interception
at a tail passing scenario (marked tail passing range 460) is much
wider than the time range for initiating the warhead 102 for a
successful interception at a head passing scenario (marked head
passing range 470), and thus less sensitive to the timing of the
warhead 102 initiation.
[0074] It can be thus appreciated that identifying a passing
scenario and taking it into consideration when calculating the
initiation time of an interceptor missile's 100 warhead 102 is
advantageous.
[0075] It is to be noted that the illustrated graph is merely an
example and it is by no means limiting. For example, in some cases
any one of the curves may be different than shown in the
illustration. In some cases, the tail passing range 460 and the
head passing range 470 can partially or completely overlap. In some
cases the minimal number of fragments 450 can be lower or higher.
In some cases, the curves can overlap (e.g. when the target has a
cubic shape). Other reasons for variations in the graph and/or the
curves and/or the optimal initiation times and/or the minimal
number of fragments and/or the head/tail passing ranges, etc., may
exist.
[0076] Having described the relevancy of the passing scenario
determination for the interception process, attention is drawn to
FIG. 5 is a flowchart illustrating an exemplary interception
process, in accordance with the presently disclosed subject
matter.
[0077] According to certain embodiments of the presently disclosed
subject matter, processing unit 200 can be configured to perform an
interception process 500 (e.g. utilizing passing direction
determination module 220 and/or initiation time determination
module 230).
[0078] For this purpose, processing unit 200 can be configured to
receive at least one reading of a range and a range rate (or
reading/s enabling determination thereof) between the interceptor
missile and a target (block 510). In some cases, the readings
received in block 510 are obtained by the spatial relativity
sensor/s 240. As indicated herein, the spatial relativity sensor/s
240 can be proximity sensors (e.g. proximity fuse/s).
[0079] Although reference is made to proximity sensors, it is to be
noted that any other sensor that can obtain data that enables
determination of range and a range rate between the interceptor
missile and a target can be used, mutatis mutandis. For example,
light sensing diodes or lasers can be utilized as sensors for
obtaining the range and the range rate or data enabling
determination thereof. It is to be noted that in some cases, there
may be a need of at least two sequential readings from the sensors
as some sensors cannot obtain data including the range and the
range rate in a single reading.
[0080] It is to be further noted that in some cases the range and a
range rate (or data enabling determination thereof) between the
interceptor missile and a target can be obtained by sensors
external to the interceptor missile 100. For example, data obtained
by a radar system that is monitoring the interception can be used
(e.g. a ground radar system or an airborne radar system, for
example carried by an airplane that can be located nearby an
estimated interception location, etc.).
[0081] In some cases, the processing unit 200 can utilize the
readings obtained in block 510 for obtaining the range of the
interceptor missile 100 to the target (its distance therefrom) and
the range rate of the interceptor missile with respect to the
target (block 520). In case the readings do not contain such range
and range rate, but data that enables determination thereof,
processing unit 200 can be configured to determine the range and
the range rate utilizing the readings.
[0082] Processing unit 200 can be further configured to determine a
passing direction of the interceptor missile 100 with respect to
the target (block 530). In some cases, the passing direction can be
determined directly utilizing the readings from the sensors. For
example, it can be determined that if the lower antenna sensed the
target, the interception scenario is a tail passing scenario,
whereas if the upper antenna sensed the target, the interception
scenario is a head passing scenario.
[0083] Based on the passing direction, the processing unit 200 can
be configured to obtain a required initiation time for initiating
the warhead (block 540). In some cases, the initiation time is
relative to T.sub.0 which is the time in which the distance between
the interceptor missile 100 and the target is minimal (the minimal
distance between the interceptor missile 100 and the target is also
referred to herein as Miss Distance, or MD). The determination of
the time to T.sub.0 (how long will it take the interceptor missile
100 and the target to get to MD) is detailed herein with reference
to FIG. 6).
[0084] Assuming for example that for a tail passing scenario the
initiation time is 10 milliseconds, this can imply that the warhead
initiation should occur 10 milliseconds before T.sub.0.
[0085] It is to be noted that the initiation time can be
pre-determined (e.g. based on a-priori knowledge and/or experiments
and/or estimates, etc.) and stored for example on data repository
210. It is to be further noted that the initiation time can in some
cases depend on one or more variables such as: target information
(e.g. a target type and/or information indicative thereof, a target
shape and/or information indicative thereof, etc.), a passing
direction, a selected part of the target to be hit, etc. Thus, for
example, assuming that the initiation time depends on a passing
direction, a target type, and a selected part of the target to hit,
having knowledge of the passing direction in a specific
interception process, a specific target type to be intercepted
during the interception process, a specific part of the specific
target to be intercepted during the interception process, can
enable retrieval of the corresponding initiation time from data
repository 210.
[0086] Processing unit 200 can be further configured to initiate
the warhead when the time to T.sub.0 is equal (or substantially
equal, e.g. within a certain range, e.g. several
milliseconds/microseconds, etc.) to the initiation time (which, as
indicated above, is relative to the time the MD is minimal) (block
550). For this purpose, in some cases, the processing unit 200 can
be configured to monitor the time to T.sub.0, and compare this time
with the initiation time.
[0087] It is to be noted that in some cases the initiation time
(T.sub.go) in case the passing direction is indicative of a
tail-passing scenario, wherein the interceptor trajectory passes
above the target, can be different than the initiation time
(T.sub.go) in case the passing direction is indicative of a
head-passing scenario, wherein the interceptor trajectory passes
below the target.
[0088] It is to be further noted that in some cases the initiation
time is determined such that the number of fragments of the
interceptor expected to hit the target, or as selected part thereof
(e.g. the front of the target or the rear of the target), is
optimal.
[0089] It is to be still further noted that the interception
process 500 is assumed to occur in a stage where neither the
interceptor missile, nor the target, accelerate. In case either one
(or both) accelerates, the acceleration needs to be calculated as
well and taken into account in the determination of the passing
scenario and in the determination of the initiation time of the
warhead 102. In addition, the interception process 500 is assumed
to occur when the target does not maneuver, however in cases the
target does maneuver, such maneuvering can also be taken into
account in the determination of the passing scenario and in the
determination of the initiation time of the warhead 102. In
addition, the interception process 500 is assumed to occur when the
target has no attack angle or a constant attack angle lower than a
certain threshold (e.g. 30/20/10/5 degrees, etc.), however in cases
the target's angle of attack is not constant, or not lower than the
threshold, the actual angle of attack of the target can also be
taken into account in the determination of the passing scenario and
in the determination of the initiation time of the warhead 102.
[0090] It is to be further noted that all or part of the processes
described with reference to blocks 510 to 550 can optionally be
performed by a combination of one or more processing units external
to the interceptor missile 100 (e.g. a processing unit of a ground
station, an airplane that launched the interceptor missile 100, a
satellite, etc.).
[0091] It is to be still further noted that in some cases, fewer,
more and/or different blocks than those shown in FIG. 5, may be
executed and not necessarily in the order prescribed in FIG. 5. In
some cases, one or more of the blocks illustrated in FIG. 5 may be
executed in a different order and/or one or more groups of blocks
may be executed simultaneously.
[0092] Turning to FIG. 6, there is shown an illustration of the
calculation of time to T.sub.0, in accordance with the presently
disclosed subject matter.
[0093] The time to T.sub.0 (the time until the interceptor missile
100 and the target arrive at the minimal distance there between)
can be calculated using a Pythagoras equation on a right triangle
as depicted in the figure. The first edge is the Miss Distance 620
itself (i.e. the minimal expected distance between the interceptor
missile and the target assuming the interceptor missile warhead
will not be initiated), which is a constant number. The hypotenuse
is the range between the interceptor missile 100 and the target
(marked R 610 in the figure). The third edge is the distance of the
interceptor missile from the point at which it will be at the
minimal distance from the target (marked Vc(t-T.sub.0) 630), and it
is calculated by multiplying the closing velocity (Vc) between the
interceptor missile and the target (i.e. the difference between the
velocity of the interceptor missile and the target) with the time
that it will take the interceptor missile 100 and the target to
arrive at the minimal distance there between (time to T.sub.0 or
t-T.sub.0, which is the purpose of the calculation).
[0094] It can be appreciated that the Pythagorean Theorem can be
applied on the right triangle, and therefore:
(Vc(t-T.sub.0)).sup.2+MD.sup.2=R.sup.2 Formula 1
[0095] In order to find t-T.sub.0, we can calculate a derivative of
formula 1 with respect to the time, and therefore:
(2Vc(t-T.sub.0))*Vc+0=2R*Rdot
[0096] Where Vc is the closing velocity between the interceptor
missile and the target, R is the range between the interceptor
missile and the target, and Rdot is the range rate (Rdot) between
the interceptor missile and the target. As Vc, R and Rdot are
known, as detailed herein, inter alia with respect to Fig, 5,
t-T.sub.0 can be calculated accordingly:
t - T 0 = R * Rdot Vc 2 ##EQU00001##
[0097] It will be understood that the subject matter contemplates
that a system or part of a system disclosed herein may be for
example, a computer. Likewise, the subject matter contemplates, for
example, a computer program being readable by a computer for
executing a method or part of a method disclosed herein. Further
contemplated by the subject matter, for example, is a computer
readable memory tangibly embodying program code readable by the
computer for executing a method or part of a method disclosed
herein.
[0098] The term "computer" should be expansively construed to cover
any electronic system which includes at least some hardware and has
data processing capabilities, even if not labeled as such. For
example, a computer may be in some cases be capable of manipulating
and/or transforming data represented as physical, such as
electronic quantities, within the registers and/or memories of the
computer into other data similarly represented as physical
quantities within the registers, memories, and/or other such
information storage, transmission and/or display elements of the
computer.
[0099] While examples of the subject matter have been shown and
described, the subject matter is not thus limited. Numerous
modifications, changes and improvements within the scope of the
subject matter will now occur to the reader.
* * * * *