U.S. patent application number 12/487907 was filed with the patent office on 2011-01-13 for aerial recovery of small and micro air vehicles.
Invention is credited to Randal W. Beard.
Application Number | 20110006151 12/487907 |
Document ID | / |
Family ID | 43426756 |
Filed Date | 2011-01-13 |
United States Patent
Application |
20110006151 |
Kind Code |
A1 |
Beard; Randal W. |
January 13, 2011 |
AERIAL RECOVERY OF SMALL AND MICRO AIR VEHICLES
Abstract
A method, apparatus, system, and computer system to facilitate
aerial recovery of an air vehicle are disclosed. In various
embodiments, a drogue is established in a drogue recovery orbit and
an air vehicle is recovered with the drogue. Establishment of the
drogue in a drogue recovery orbit may include establishment of a
mothership in a mothership recovery orbit or actuating control
surfaces on the drogue. Recovering the air vehicle may include
maneuvering the drogue and the air vehicle in a cooperative manner
to facilitate recovery of the air vehicle or utilizing a homing
device on the drogue to guide the air vehicle. The various
techniques disclosed may be modified to compensate for wind.
Inventors: |
Beard; Randal W.; (Provo,
UT) |
Correspondence
Address: |
AUSTIN RAPP & HARDMAN
170 South Main Street, Suite 735
SALT LAKE CITY
UT
84101
US
|
Family ID: |
43426756 |
Appl. No.: |
12/487907 |
Filed: |
June 19, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61132646 |
Jun 20, 2008 |
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Current U.S.
Class: |
244/3 ; 244/110F;
244/138R |
Current CPC
Class: |
B64C 2201/028 20130101;
B64C 39/028 20130101; B64D 3/00 20130101; B64C 2201/182
20130101 |
Class at
Publication: |
244/3 ;
244/138.R; 244/110.F |
International
Class: |
B64D 3/00 20060101
B64D003/00; B64D 17/00 20060101 B64D017/00; B64F 1/02 20060101
B64F001/02 |
Claims
1. A method comprising: establishing a drogue in a drogue recovery
orbit; and recovering an air vehicle with the drogue.
2. The method of claim 1, wherein establishing the drogue in a
drogue recovery orbit comprises: establishing a mothership in a
mothership recovery orbit.
3. The method of claim 1, wherein establishing the drogue in a
drogue recovery orbit comprises: actuating one or more control
surfaces of the drogue.
4. The method of claim 3, wherein the drogue recovery orbit has a
radius greater than a minimum turning radius of the air vehicle,
and wherein the drogue has an airspeed that is less than an
airspeed of the air vehicle.
5. The method of claim 1, wherein recovering the air vehicle
comprises: maneuvering the drogue and the air vehicle in a
cooperative manner to facilitate recovery of the air vehicle.
6. The method of claim 1, wherein recovering the air vehicle
comprises: utilizing a homing device on the drogue to guide the air
vehicle.
7. The method of claim 1, further comprising: compensating for
wind.
8. An apparatus to recover an air vehicle, the apparatus
comprising: an aerodynamic main body portion; at least one control
surface located on the main body portion; a catch mechanism coupled
to the main body portion, the catch mechanism to facilitate
recovery of an air vehicle; and a homing device coupled to the main
body portion to guide the air vehicle during recovery.
9. The apparatus of claim 8, wherein the aerodynamic main body
portion comprises: one or more wings.
10. The apparatus of claim 8, wherein the catch mechanism is
active.
11. The apparatus of claim 8, wherein the catch mechanism is
passive.
12. The apparatus of claim 11, wherein the catch mechanism
comprises: at least one of an open cavity located within an
interior of the main body portion, a closeable cavity located
within the interior of the main body portion, and a dragnet coupled
to the main body portion.
13. The apparatus of claim 8, wherein the homing device comprises:
at least one of a color marker, an infrared marker, an acoustic
beacon, and an electromagnetic beacon.
14. The apparatus of claim 8, further comprising: an attachment
mechanism to attach the main body portion to a mothership with a
tow cable.
15. A system comprising: a mothership; and a drogue coupled to the
mothership by a tow cable, the drogue comprising: an aerodynamic
main body portion; at least one control surface located on the main
body portion; a catch mechanism coupled to the main body portion,
the catch mechanism to facilitate recovery of an air vehicle; and a
homing device coupled to the main body portion to guide the air
vehicle during recovery.
16. The system of claim 15, wherein the aerodynamic main body
portion comprises: one or more wings.
17. The system of claim 15, wherein the catch mechanism comprises:
at least one of an open cavity located within an interior of the
main body portion, a closeable cavity located within the interior
of the main body portion, and a dragnet coupled to the main body
portion.
18. The system of claim 15, wherein the homing device comprises: at
least one of a color marker, an infrared marker, an acoustic
beacon, and an electromagnetic beacon.
Description
RELATED APPLICATIONS
[0001] This application is related to and claims priority from U.S.
Patent Application Ser. No. 61/132,646 filed Jun. 20, 2008, for
"Aerial Recovery of Small and Micro Air Vehicles," with inventor
Randal W. Beard, which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates generally to unmanned aerial
vehicles. More specifically, the present disclosure relates to
aerial recovery of small and micro unmanned aerial vehicles.
BACKGROUND
[0003] Due to recent directives from the Department of Defense,
there is great pressure to develop the technology behind unmanned
aerial vehicles (UAVs). UAVs are remotely piloted or autonomous
aircraft that can carry cameras, sensors, communications equipment,
or other payloads.
[0004] UAVs have proven their usefulness in military applications
in recent years. Large UAVs have become an integral part of the
U.S. arsenal. Large UAVs have executed surveillance and tactical
missions in virtually every part of the world. For example,
unmanned aircraft systems ("UAS") have become an essential tool for
warfighters. While high-altitude, long-endurance UAS like the
Predator and the Global Hawk provide persistent intelligence,
surveillance, and reconnaissance ("ISR") capabilities, they are a
scarce resource that cannot be given specific data-gathering tasks
by individual troops. At the other end of the spectrum are
backpackable small and micro air vehicles ("MAVs"), with wingspans
less than 48 inches, which theoretically can be carried by every
warfighter.
[0005] One drawback of MAVs is the recovery of the MAV after it has
completed its mission. Although the relatively low cost of MAVs may
suggest that they may be expendable (and thereby removing the need
for recovery), MAVs still contain critical and often classified
technology that needs to be kept out of enemy hands. Thus,
innovative recovery techniques are critical to ubiquitous use of
MAV technology.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a flow diagram illustrating an embodiment of a
method of recovering an air vehicle.
[0007] FIG. 2 is a diagram illustrating an embodiment of a system
that may be used to recover an air vehicle.
[0008] FIG. 3 is a diagram illustrating one embodiment of a drogue
that may be used to recover an air vehicle.
[0009] FIG. 4 is a diagram illustrating another embodiment of a
drogue that may be used to recover an air vehicle.
[0010] FIG. 5 is a diagram illustrating yet another embodiment of a
drogue that may be used to recover an air vehicle.
DETAILED DESCRIPTION
[0011] The word "exemplary" is used herein to mean "serving as an
example, instance, or illustration." Any embodiment described
herein as "exemplary" is not necessarily to be construed as
preferred or advantageous over other embodiments. In addition,
references to "an," "one," "other," "another," "the," "this,"
"alternative," or "various" embodiments should not be construed as
limiting since various aspects of the disclosed embodiments may be
used interchangeably within other embodiments.
[0012] A method, apparatus, system, and computer system are
disclosed to facilitate aerial recovery of an air vehicle (e.g.,
MAV). One embodiment of the method may include establishing a
drogue in a drogue recovery orbit and recovering an air vehicle
with the drogue. In various embodiments, one or more of the
following may also be part of the method: establishing a mothership
in a mothership recovery orbit; actuating one or more control
surfaces of the drogue; maneuvering the drogue and the air vehicle
in a cooperative manner to facilitate recovery of the air vehicle;
utilizing a homing device on the drogue to guide the air vehicle;
and compensating for wind.
[0013] One embodiment of the apparatus (e.g., drogue) may include
an aerodynamic main body portion, at least one control surface
located on the main body portion, a catch mechanism coupled to the
main body portion, the catch mechanism to facilitate recovery of an
air vehicle, and a homing device coupled to the main body portion
to guide the air vehicle during recovery. The apparatus may also
include an attachment mechanism to attach the main body portion to
a mothership with a tow cable. In various embodiments, the catch
mechanism may comprise at least one of an open cavity located
within an interior of the main body portion, a closeable cavity
located within the interior of the main body portion, and a dragnet
coupled to the main body portion. In various embodiments, the
homing device may comprise at least one of a color marker, an
infrared marker, an acoustic beacon, and an electromagnetic
beacon.
[0014] One embodiment of the system may include a mothership and a
drogue coupled to the mothership by a tow cable, the drogue
comprising an aerodynamic main body portion, at least one control
surface located on the main body portion, a catch mechanism coupled
to the main body portion, the catch mechanism to facilitate
recovery of an air vehicle, and a homing device coupled to the main
body portion to guide the air vehicle during recovery. In various
embodiments, the catch mechanism may comprise at least one of an
open cavity located within an interior of the main body portion, a
closeable cavity located within the interior of the main body
portion, and a dragnet coupled to the main body portion. In various
embodiments, the homing device may comprise at least one of a color
marker, an infrared marker, an acoustic beacon, and an
electromagnetic beacon.
[0015] One embodiment of the computer system may include a
processor, memory in electronic communication with the processor,
and instructions stored in the memory, the instructions being
executable to establish a drogue in a drogue recovery orbit and
recover an air vehicle with the drogue. In various embodiments, the
computer system may control one or more elements of the system
(e.g., mothership, drogue, air vehicle). In various embodiments,
the memory may further include instructions being executable to
perform one or more of the following: establishing a mothership in
a mothership recovery orbit; actuating one or more control surfaces
of the drogue; maneuvering the drogue and the air vehicle in a
cooperative manner to facilitate recovery of the air vehicle; and
compensating for wind.
[0016] Backpackable MAVs enable warfighters on the ground to gather
time-critical, over-the-hill ISR information. However, retrieving
the MAV is problematic because landing the vehicle near the soldier
could disclose his/her location to an enemy. Another potential
application of MAVs is collecting battle damage information. For
example, the MAV could piggyback on munitions until several seconds
before impact, when it is deployed so that it can circle the target
to assess the damage caused by the munitions. Again for this
application, retrieval of the MAV after it has performed its
mission is difficult because target locations are often deep in
enemy territory, and the MAV may not have enough fuel to return
home.
[0017] A third potential application of MAV technology is to assist
gunship operators to track and prosecute multiple targets. For
example, enemy combatants may separate and flee in multiple
directions when there is a threat of attack by a gunship. The
gunship could potentially deploy multiple MAVs to assist in
tracking the combatants as they flee. Yet again, it is difficult to
retrieve the MAV after it has completed its mission, primarily
because the airspeed of the gunship, which may be approximately 200
knots, is so much greater than the airspeed of the MAV, which may
be approximately 30-40 knots. There are numerous other applications
where MAVs could be used to safely gather high resolution ISR data
but for which retrieval of the asset is problematic.
[0018] The primary difficulty with aerial recovery is the relative
size and speed of the mothership compared to the MAV. Aerial
recovery is much like aerial refueling where the goal is to extend
the operational lifetime of the asset. However, in aerial
refueling, the fighter jet and the tanker can match their
airspeeds, which is not possible with MAVs and larger aircraft. The
embodiments disclosed herein may facilitate aerial recovery of
existing MAVs using a much larger fixed wing mothership. The
mothership could either be unmanned (e.g., Predator) or manned
(e.g., AC-130).
[0019] Referring now to FIG. 1, an embodiment of a method is shown.
The method begins by establishing a drogue in a drogue recovery
orbit at block 100. As used herein, a "drogue" refers to a device
to be towed by an aircraft (e.g., mothership) to facilitate the
recovery of an air vehicle (e.g., a small or micro air vehicle). In
various embodiments, recovery of the air vehicle is conducted in
the air (e.g., an aerial recovery). As used herein, a "drogue
recovery orbit" refers to an orbit in which the drogue is
established to facilitate recovery of an air vehicle.
[0020] In various embodiments, the drogue recovery orbit may be an
orbit in which the drogue maintains substantially the same altitude
while flying in a generally circular pattern. In other embodiments,
the drogue recovery orbit may have patterns that are not circular.
Thus, any shape orbit may be utilized to facilitate recovery of an
air vehicle. Furthermore, a particular orbit shape may be utilized
to compensate for one or more environmental factors (e.g., wind,
avoiding detection, evading enemy attacks) while attempting to
recover an air vehicle. For example, the drogue recovery orbit may
be generally elliptical. In other embodiments, the altitude of the
drogue may be intentionally varied while in the drogue recovery
orbit to facilitate recovery of an air vehicle.
[0021] Establishment of the drogue in a drogue recovery orbit may
be achieved in various embodiments by establishing a mothership,
which is towing the drogue, in a mothership recovery orbit. As used
herein, a "mothership recovery orbit" refers to an orbit in which
the mothership is established to facilitate recovery of an air
vehicle. Similar to the drogue recovery orbit discussed above, the
mothership recovery orbit may be an orbit in which the mothership
maintains substantially the same altitude while flying in a
generally circular pattern. In other embodiments, the mothership
recovery orbit may have patterns that are not circular. Thus, any
shape orbit may be utilized to facilitate recovery of an air
vehicle. Furthermore, a particular orbit shape may be utilized to
compensate for one or more environmental factors (e.g., wind,
avoiding detection, evading enemy attacks) while attempting to
recover an air vehicle. For example, the mothership recovery orbit
may be generally elliptical. In other embodiments, the altitude of
the mothership may be intentionally varied while in the mothership
recovery orbit to facilitate recovery of an air vehicle.
[0022] In other embodiments, establishment of the drogue in a
drogue recovery orbit may be achieved by actuating one or more
control surfaces of the drogue. These control surfaces may be any
type of control surface used in aviation to control the flight path
and characteristics of an air vehicle. Examples of control surfaces
that may be actuated to establish the drogue in a drogue recovery
orbit can be seen below in connection with the discussion of FIGS.
3-5.
[0023] In various embodiments, the drogue recovery orbit may have a
radius greater than a minimum turning radius of the air vehicle to
be recovered. During recovery, the drogue may be controlled to have
an airspeed that is less than the airspeed of the air vehicle to be
recovered. In various embodiments, the airspeed of the air vehicle
is a nominal airspeed, and the airspeed of the drogue is less than
the nominal airspeed of the air vehicle to be recovered.
[0024] At block 102, an air vehicle is recovered with the drogue.
In various embodiments, recovery of the air vehicle includes
maneuvering the drogue and the air vehicle in a cooperative manner
to facilitate recovery of the air vehicle. This maneuvering in a
cooperative manner may include, for example, controlling both the
drogue and air vehicle to move towards a common point or to reduce
the relative distance between the drogue and the air vehicle to
facilitate recovery.
[0025] In various embodiments, recovery of the air vehicle includes
utilizing a homing device on the drogue to guide the air vehicle.
The homing device may be active, passive, or have components that
are both active and passive. Examples of passive homing devices
include a color marker, an infrared marker, an acoustic beacon, and
an electromagnetic beacon. In various embodiments, the air vehicle
may use vision-based sensors, for example, to maintain a constant
image of the target (e.g., a capture mechanism associated with the
drogue) during the final stage of recovery. If the image "moves"
while the air vehicle is approaching the drogue, the air vehicle
may actuate its control surface(s) to reacquire the desired
approach image by the vision-based sensors. It is worth noting that
other sensor systems may be used.
[0026] At any stage of the method shown in FIG. 1, it may be
advantageous to compensate for wind, which may cause the drogue
recovery orbit to become "tilted." A "tilt" refers to a situation
in which the drogue experiences unintentional altitude variations
while in the drogue recovery orbit. These altitude variations may
be caused by the wind.
[0027] Compensation for the wind may be achieved by using several
different techniques, alone or in combination. For example, as
discussed above, the mothership recovery orbit may be "tilted" in
one embodiment by varying the altitude of the mothership during the
mothership recovery orbit. Also, the shape of the mothership
recovery orbit (e.g., circular, elliptical, etc.) may be varied to
compensate for wind. In other embodiments, the orbit of the air
vehicle may be "tilted" by varying the altitude of the air vehicle
as recovery of the air vehicle is attempted. In another embodiment,
a winch may be used to deploy the tow cable (e.g., from the
mothership) that is connected to the drogue, and thus, the winch
may be used to vary the length of the tow cable to compensate for
the effect of the wind on the drogue. In various embodiments, one
or more of the control surfaces of the drogue may be actuated to
control the flight path of the drogue to compensate for wind.
[0028] Referring now to FIG. 2, system 200 is shown that may be
used to recover an air vehicle. System 200 includes mothership 202
that is shown flying in mothership recovery orbit 204. Mothership
202 may be manned or unmanned. Mothership recovery orbit 204 has
radius (R) 206, and mothership 202 is traveling at speed (V) 208.
Drogue 210 is coupled to mothership 202 by tow cable 212, which has
length (I) 212.
[0029] Drogue 210 is flying in drogue recovery orbit 214. Drogue
recovery orbit 214 has radius (r) 216. In various embodiments,
radius 216 of drogue recovery orbit 214 is significantly smaller
than radius 206 of mothership recovery orbit 204. Drogue 210 is
shown traveling at speed (v.sub.d) 218. In various embodiments,
speed 218 of drogue 210 is significantly less than speed 208 of
mothership 202.
[0030] Air vehicle 220 (e.g., MAV) is shown flying towards drogue
recovery orbit 214 in order to be recovered by drogue 210. Air
vehicle 220 is shown flying at speed (v) 222. As discussed above,
speed 218 of drogue 210 is less than speed 222 of air vehicle 220
so that air vehicle 220 may over take drogue 210 once air vehicle
220 has entered drogue recovery orbit 214.
[0031] Referring now to FIG. 3, one embodiment of a drogue is
shown. Drogue 300 includes aerodynamic main body portion 302 and
control surfaces 304 located on main body portion 302. Control
surfaces 304 include elevons 304a. Elevons are a combination of
elevators and ailerons. Control surfaces 304 also include rudders
304b. It is worth noting that other numbers, types, and
configurations of control surfaces may be used.
[0032] Drogue 300 additionally includes catch mechanism 306 coupled
to main body portion 302. Catch mechanism 306 is an open cavity
located within an interior of main body portion 302 and is designed
to facilitate recovery of an air vehicle. In various embodiments,
catch mechanism 306 is lined with one type of hook-and-loop
fastening material, and the air vehicle to be recovered has a
complementary type of hook-and-loop fastening material disposed
thereon to facilitate recovery. Although, other material could be
used to line catch mechanism 306 to facilitate recovery of an air
vehicle.
[0033] Drogue 300 also includes homing device 308 coupled to main
body portion 302 to guide the air vehicle during recovery. As
mentioned above, homing device 308 may be active, passive, or have
components that are both active and passive. Examples of passive
homing devices include a color marker, an infrared marker, an
acoustic beacon, and an electromagnetic beacon.
[0034] Drogue 300 has wings 310 coupled to main body portion 302.
Wings 310 are designed to impart lift to drogue 300 while in
flight. Attachment mechanism 312 is coupled to the front of main
body portion 302 and is designed to attach main body portion 302 to
a mothership with tow cable 314.
[0035] Referring now to FIG. 4, another embodiment of a drogue is
shown. Drogue 400 includes aerodynamic main body portion 402, which
is designed to create lift while flying. The shape of main body
portion 402 may be similar to that of stealth aircraft that have a
"flying wing" design. Drogue 400 also includes control surfaces 404
located on main body portion 402. Control surfaces 404 include
elevons 404a. Control surfaces 404 also include rudders 404b. It is
worth noting that other numbers, types, and configurations of
control surfaces may be used.
[0036] Drogue 400 additionally includes catch mechanism 406 coupled
to main body portion 402. Catch mechanism 406 is a closeable cavity
located within the interior of main body portion 402 and is
designed to facilitate recovery of an air vehicle. As shown in FIG.
4, catch mechanism 406 is illustrated in an open configuration,
ready to recover an air vehicle. The dashed line in FIG. 4
indicates trailing edge 410 of main body portion 402 when catch
mechanism 406 is in a closed configuration. In various embodiments,
catch mechanism 406 is lined with one type of hook-and-loop
fastening material, and the air vehicle to be recovered has a
complementary type of hook-and-loop fastening material disposed
thereon to facilitate recovery. Although, other material could be
used to line catch mechanism 406 to facilitate recovery of an air
vehicle.
[0037] Drogue 400 also includes homing device 408 coupled to main
body portion 402 to guide the air vehicle during recovery. As
mentioned above, homing device 408 may be active, passive, or have
components that are both active and passive. Examples of passive
homing devices include a color marker, an infrared marker, an
acoustic beacon, and an electromagnetic beacon. Attachment
mechanism 412 is coupled to the front of main body portion 402 and
is designed to attach main body portion 402 to a mothership with
tow cable 414.
[0038] Referring now to FIG. 5, another embodiment of a drogue is
shown. Drogue 500 includes aerodynamic main body portion 502 and
control surfaces 504 located on main body portion 502. Control
surfaces 504 include elevons 504a. Control surfaces 504 also
include rudders 504b. It is worth noting that other numbers, types,
and configurations of control surfaces may be used.
[0039] Drogue 500 additionally includes catch mechanism 506 coupled
to main body portion 502. Catch mechanism 506 is a dragnet coupled
to main body portion 502 and is designed to facilitate recovery of
an air vehicle. In various embodiments, catch mechanism 506 is
lined with one type of hook-and-loop fastening material, and the
air vehicle to be recovered has a complementary type of
hook-and-loop fastening material disposed thereon to facilitate
recovery. Although, other material could be used to line catch
mechanism 506 to facilitate recovery of an air vehicle.
[0040] Drogue 500 has wings 508 coupled to main body portion 502.
Wings 508 are designed to impart lift to drogue 500 while in
flight. Attachment mechanism 510 is coupled to the front of main
body portion 502 and is designed to attach main body portion 502 to
a mothership with tow cable 512.
[0041] Although not shown in the figures, the drogue may have an
autopilot system that is capable of actuating the one or more
control surfaces in order to establish and maintain a drogue
recovery orbit. In addition, the drogue and the air vehicle may
each have a Global Positioning System ("GPS") receiver that can
provide information that can be used to bring the drogue and the
air vehicle within 3-5 meters of each other, at which point the air
vehicle may utilize the homing device on the drogue for guidance
during the final stage of recovery. The autopilot of the drogue may
also be used to cooperatively maneuver the drogue during the final
stage of recovery of the air vehicle.
[0042] In operation, each component of the system (e.g.,
mothership, drogue, air vehicle) may be controlled by software. In
various embodiments, control software may be resident on each
component, respectively (e.g., control software for mothership may
be resident on the mothership). In other embodiments, the control
software for all of the components may be resident in one location
(e.g., mothership or on a remote computer system). In still other
embodiments, the location of the control software may be a
combination of these examples.
[0043] Regardless of the location of the control software, there
may be a user interface in various embodiments for a user to
control the overall system (e.g., programming one or more of the
components, inputting environmental factors that need to be
considered for recovery of an air vehicle, manually controlling one
or more components, etc). In one embodiment, the user interface may
be a laptop computer. In other embodiments, the user interface may
be a desktop computer, a personal digital assistant, a tablet
personal computer ("PC"), or other similar devices. The user
interface may be physically connected to one or more of the system
components. In other embodiments, the user interface may be in
wireless communication with one or more of the system
components.
[0044] The various illustrative logical blocks, modules, circuits,
and algorithm steps described in connection with the embodiments
disclosed herein may be implemented as electronic hardware,
computer software, or combinations of both. To clearly illustrate
this interchangeability of hardware and software, various
illustrative components, blocks, modules, circuits, and steps have
been described above generally in terms of their functionality.
Whether such functionality is implemented as hardware or software
depends upon the particular application and design constraints
imposed on the overall system. Skilled artisans may implement the
described functionality in varying ways for each particular
application, but such implementation decisions should not be
interpreted as causing a departure from the scope of the disclosed
embodiments.
[0045] The methods disclosed herein comprise one or more steps or
actions for achieving the described method. The method steps and/or
actions may be interchanged with one another without departing from
the scope of the claims. In other words, unless a specific order of
steps or actions is required for proper operation of the method
that is being described, the order and/or use of specific steps
and/or actions may be modified without departing from the scope of
the claims.
[0046] It is to be understood that the claims are not limited to
the precise configuration and components illustrated above. Various
modifications, changes and variations may be made in the
arrangement, operation and details of the systems, methods, and
apparatus described herein without departing from the scope of the
claims.
* * * * *