U.S. patent application number 13/363011 was filed with the patent office on 2012-07-19 for submersible vehicles and methods for transiting the same in a body of liquid.
This patent application is currently assigned to iRobot Corporation. Invention is credited to Ryan Moody, Frederick Vosburgh.
Application Number | 20120180712 13/363011 |
Document ID | / |
Family ID | 41115191 |
Filed Date | 2012-07-19 |
United States Patent
Application |
20120180712 |
Kind Code |
A1 |
Vosburgh; Frederick ; et
al. |
July 19, 2012 |
SUBMERSIBLE VEHICLES AND METHODS FOR TRANSITING THE SAME IN A BODY
OF LIQUID
Abstract
A submersible vehicle for use in a body of liquid includes a
vehicle body, a pair of fins coupled to the vehicle body on-opposed
sides thereof, and a dihedral angle control system. The dihedral
angle control is system operative to vary a fin dihedral angle of
each of the fins.
Inventors: |
Vosburgh; Frederick;
(Durham, NC) ; Moody; Ryan; (Durham, NC) |
Assignee: |
iRobot Corporation
|
Family ID: |
41115191 |
Appl. No.: |
13/363011 |
Filed: |
January 31, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12408177 |
Mar 20, 2009 |
8127704 |
|
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13363011 |
|
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|
61039658 |
Mar 26, 2008 |
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Current U.S.
Class: |
114/330 |
Current CPC
Class: |
B63G 8/22 20130101; B63G
8/42 20130101; B63G 8/001 20130101; B63G 8/18 20130101; B63G
2008/002 20130101; H01F 7/0252 20130101 |
Class at
Publication: |
114/330 |
International
Class: |
B63G 8/14 20060101
B63G008/14; B63G 8/08 20060101 B63G008/08; B63B 21/66 20060101
B63B021/66 |
Claims
1. A submersible vehicle for use in a body of liquid, the
submersible vehicle comprising: a vehicle body; a pair of fins
coupled to the vehicle body on opposed sides thereof; and a
dihedral angle control system operative to vary a fin dihedral
angle of each of the fins.
2. The submersible vehicle of claim 1 wherein the submersible
vehicle is an underwater glider.
3. The submersible vehicle of claim 1 wherein the fin dihedral
angle of each of the fins is upward when the submersible vehicle is
descending and downward when the submersible vehicle is
ascending.
4. The submersible vehicle of claim 1 wherein the submersible
vehicle is a towed vehicle.
5. The submersible vehicle of claim 1 wherein the submersible
vehicle includes an active thrust system operative to propel the
submersible vehicle through the body of liquid.
6. The submersible vehicle of claim 1 wherein each fin is joined to
the body at a respective fin root and pivots about a pivot axis at
the fin root to vary the fin dihedral angle of the fin.
7. The submersible vehicle of claim 6 including a pair of opposed
stops associated with each fin and configured to limit the range of
fin dihedral angles assumable by the fin.
8. The submersible vehicle of claim 1 wherein the dihedral angle
control system is operative to passively vary the fin dihedral
angle of each of the fins.
9. The submersible vehicle of claim 1 wherein the dihedral angle
control system includes a biasing member to change and/or maintain
a dihedral angle of at least one of the fins.
10. The submersible vehicle of claim 1 wherein the dihedral angle
control system includes at least one magnet or magnetic actuator to
induce each of the fins into at least one selected fin dihedral
angle.
11. The submersible vehicle of claim 1 wherein the dihedral angle
control system is operative to actively vary the fin-dihedral angle
of each of the fins
12. The submersible vehicle of claim 11 wherein the dihedral angle
control system includes: at least one force actuator operable to
forcibly vary the fin dihedral angles of the fins; and a force
actuator controller to control actuation of the force actuator.
13. The submersible vehicle of claim 1 wherein the fins pivot
independently of one another to position the fins at different
respective fin dihedral angles from one another.
14. A method of providing transit of a submersible vehicle through
a body of liquid, the submersible vehicle including a vehicle body
and a pair of fins coupled to the vehicle body on opposed sides
thereof, the method comprising: varying a fin dihedral angle of
each of the fins using a dihedral angle control system.
15. The method of claim 14 including: positioning each fin to have
an upward fin dihedral angle when the submersible vehicle is
descending; and positioning each fin to have a downward fin
dihedral angle when the submersible vehicle is ascending.
16. The method of claim 14 wherein varying the fin dihedral angle
of each of the fins includes actively varying the fin dihedral
angle of each of the fins using the dihedral angle control
system.
17. The method of claim 16 wherein: the dihedral angle control
system includes: at least one force actuator operable to forcibly
vary the fin dihedral angles of the fins; and a force actuator
controller; and the method includes controlling actuation of the
force actuator using the force actuator controller.
18. The method of claim 14 wherein varying the fin dihedral angle
of each of the fins includes pivoting the fins independently of one
another to position the fins at different respective fin dihedral
angles from one another.
19. The method of claim 18 including raising one of the fins to an
upward fin dihedral angle and lowering the other fin to a downward
fin dihedral angle to cause or assist turning of the submersible
vehicle.
Description
RELATED APPLICATION(S)
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/408,177, filed Mar. 20, 2009, which claims
the benefit of and priority from U.S. Provisional Patent
Application Ser. No. 61/039,658, filed Mar. 26, 2008, the
disclosures of which are incorporated herein by reference in their
entireties.
FIELD OF THE INVENTION
[0002] The present invention relates to submersible vehicles and
methods for transiting the same.
BACKGROUND OF THE INVENTION
[0003] Monitoring of the oceans and other bodies of water for
purposes of scientific research, national defense, or commercial
development is becoming increasingly automated to reduce costs. For
example, unmanned undersea vehicles (UUV) have emerged as key tools
in the offshore engineering industry. And considerable investment
is being made by nations around the world to develop UUVs for
national or homeland defense. With the increasing requirement for
persistent intelligence, surveillance and reconnaissance (ISR)
operations in areas where access is denied or where ISR is
otherwise desirably clandestine, UUVs will be increasingly put to
use. Use of UUVs to service devices historically tended by
submarines, deep submersible vehicles and divers will substantially
reduce cost and risk to the operators. So, it can be seen,
persistent ISR and other activities in problematic areas drive the
need for means of sensing and communicating that do not require
human intervention or costly engineering systems.
[0004] Aquatic gliders are UUVs that are used for persistent ocean
sensing. An aquatic glider may glide up and down through the water
column for months at a time, driven by small changes in buoyancy
provided by a buoyancy engine. Gliders used by the U.S. Navy
include those offered by Webb Research in Falmouth, Mass., by the
University of Washington in Seattle, Wash. and by Bluefin Robotics
in Cambridge, Mass. These gliders have a fixed wing or wings that
can convert a portion of buoyancy driven vertical movement into
horizontal movement as means of providing transit without
propellers.
[0005] Such a glider can transit great distances because the
buoyancy engine uses only small amounts of power, intermittently at
the end of each up glide or down glide portion of its saw-tooth
glide cycle path through the water. This intermittent use of energy
conserves battery power and extends mission duration. Mission
duration may come, however, at the expense of speed and
maneuverability. Long-endurance gliders typically make only a
fraction of a knot through the water and maneuver poorly, limiting
their ability to penetrate shallower or more constrained areas of
operation.
SUMMARY OF THE INVENTION
[0006] According to embodiments of the present invention, a
submersible vehicle for use in a body of liquid includes a vehicle
body, a pair of fins coupled to the vehicle body on opposed sides
thereof, and a dihedral angle control system. The dihedral angle
control is system operative to vary a fin dihedral angle of each of
the fins.
[0007] In some embodiments, the submersible vehicle is an aquatic
glider. The glider may include a buoyancy control system operable
to selectively generate vertical force on the submersible vehicle
by varying a buoyancy of the submersible vehicle, and the
submersible vehicle is configured to generate a glide thrust
responsive to changes in elevation of the submersible vehicle.
According to some embodiments, the fin dihedral angle of each of
the fins is upward when the submersible vehicle is descending and
downward when the submersible vehicle is ascending.
[0008] In some embodiments, the submersible vehicle is a towed
vehicle.
[0009] In some embodiments, the submersible vehicle includes an
active thrust system operative to propel the submersible vehicle
through the body of liquid.
[0010] According to some embodiments, each fin is joined to the
body at a respective fin root and pivots about a pivot axis at the
fin root to vary the fin dihedral angle of the fin. The submersible
vehicle may include a pair of opposed stops associated with each
fin and configured to limit the range of fin dihedral angles
assumable by the fin.
[0011] According to some embodiments, the dihedral angle control
system is operative to passively vary the fin dihedral angle of
each of the fins.
[0012] In some embodiments, the dihedral angle control system
includes at least one biasing member to change and/or maintain a
dihedral angle of at least one of the fins.
[0013] The dihedral angle control system may include at least one
magnet or magnetic actuator to induce each of the fins into at
least one selected fin dihedral angle.
[0014] In some embodiments, the dihedral angle control system is
operative to actively vary the fin dihedral angle of each of the
fins. According to some embodiments, the dihedral angle control
system includes: at least one magnetic actuator to induce each of
the fins into at least one selected fin dihedral angle; and a
magnet force controller to control an attraction force of the at
least one magnetic actuator. According to some embodiments, the
dihedral angle control system includes: at least one force actuator
operable to forcibly vary the fin dihedral angles of the fins; and
a force actuator controller to control actuation of the force
actuator.
[0015] In some embodiments, the fins pivot independently of one
another to position the fins at different respective fin dihedral
angles from one another.
[0016] According to method embodiments of the present invention, a
method of providing transit of a submersible vehicle through a body
of liquid, the submersible vehicle including a vehicle body and a
pair of fins coupled to the vehicle body on opposed sides thereof,
includes varying a fin dihedral angle of each of the fins using a
dihedral angle control system.
[0017] According to some embodiments, the submersible vehicle is a
glider including a buoyancy control system, the method including
using the buoyancy control system, selectively generating vertical
force on the submersible vehicle by varying a buoyancy of the
submersible vehicle and thereby changing the elevation of the
submersible vehicle in the water, responsive to which the
submersible vehicle generates a glide thrust on the submersible
vehicle. In some embodiments, the method includes: positioning each
fin to have an upward fin dihedral angle when the submersible
vehicle is descending; and positioning each fin to have a downward
fin dihedral angle when the submersible vehicle is ascending.
[0018] In some embodiments, varying the fin dihedral angle of each
of the fins includes actively varying the fin dihedral angle of
each of the fins using the dihedral angle control system. According
to some embodiments, the dihedral angle control system includes: at
least one magnetic actuator to induce each of the fins into at
least one selected fin dihedral angle; and a magnet force
controller; and the method includes controlling an attraction force
of the at least one magnetic actuator using the magnet force
controller. According to some embodiments, the dihedral angle
control system includes: at least one force actuator operable to
forcibly vary the fin dihedral angles of the fins; and a force
actuator controller; and the method includes controlling actuation
of the force actuator using the force actuator controller.
[0019] According to some embodiments, varying the fin dihedral
angle of each of the fins includes pivoting the fins independently
of one another to position the fins at different respective fin
dihedral angles from one another. The method may include raising
one of the fins to an upward fin dihedral angle and lowering the
other fin to a downward fin dihedral angle to cause or assist
turning of the submersible vehicle.
[0020] Further features, advantages and details of the present
invention will be appreciated by those of ordinary skill in the art
from a reading of the figures and the detailed description of the
preferred embodiments that follow, such description being merely
illustrative of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a front perspective view of a submersible vehicle
according to embodiments of the present invention.
[0022] FIG. 2 is a schematic front view of the submersible vehicle
of FIG. 1 wherein fins thereof are each positioned with a positive
dihedral angle.
[0023] FIG. 3 is a schematic front view of the submersible vehicle
of FIG. 1 wherein the fins are each positioned with a negative
dihedral angle.
[0024] FIG. 4 is a schematic diagram illustrating a travel path of
the submersible vehicle of FIG. 1.
[0025] FIG. 5 is a front perspective view of the submersible
vehicle of FIG. 1 executing a banking turn maneuver.
[0026] FIG. 6 is an enlarged, fragmentary, front view of a
submersible vehicle according to further embodiments of the present
invention.
[0027] FIG. 7 is an enlarged, fragmentary, front view of a
submersible vehicle according to further embodiments of the present
invention.
[0028] FIG. 8 is an enlarged, fragmentary, front view of a
submersible vehicle according to further embodiments of the present
invention.
[0029] FIG. 9 is an enlarged, fragmentary, front view of a
submersible vehicle according to further embodiments of the present
invention.
[0030] FIG. 10 is an enlarged, fragmentary, front view of a
submersible vehicle according to further embodiments of the present
invention.
[0031] FIG. 11 is a front perspective view of a submersible vehicle
according to further embodiments of the present invention.
[0032] FIG. 12 is a schematic view of a glider tow system according
to further embodiments of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0033] The present invention now will be described more fully
hereinafter with reference to the accompanying drawings, in which
illustrative embodiments of the invention are shown. In the
drawings, the relative sizes of regions or features may be
exaggerated for clarity. This invention may, however, be embodied
in many different forms and should not be construed as limited to
the embodiments set forth herein; rather, these embodiments are
provided so that this disclosure will be thorough and complete, and
will fully convey the scope of the invention to those skilled in
the art.
[0034] It will be understood that when an element is referred to as
being "coupled" or "connected" to another element, it can be
directly coupled or connected to the other element or intervening
elements may also be present. In contrast, when an element is
referred to as being "directly coupled" or "directly connected" to
another element, there are no intervening elements present. Like
numbers refer to like elements throughout. As used herein the term
"and/or" includes any and all combinations of one or more of the
associated listed items.
[0035] In addition, spatially relative terms, such as "under",
"below", "lower", "over", "upper" and the like, may be used herein
for ease of description to describe one element or feature's
relationship to another element(s) or feature(s) as illustrated in
the figures. It will be understood that the spatially relative
terms are intended to encompass different orientations of the
electronics device in use or operation in addition to the
orientation depicted in the figures. For example, if the
electronics device in the figures is turned over, elements
described as "under" or "beneath" other elements or features would
then be oriented "over" the other elements or features. Thus, the
exemplary term "under" can encompass both an orientation of over
and under. The electronics device may be otherwise oriented
(rotated 90 degrees or at other orientations) and the spatially
relative descriptors used herein interpreted accordingly.
[0036] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
[0037] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. It will be further understood that terms, such
as those defined in commonly used dictionaries, should be
interpreted as having a meaning that is consistent with their
meaning in the context of the relevant art and will not be
interpreted in an idealized or overly formal sense unless expressly
so defined herein. Well-known functions or constructions may not be
described in detail for brevity and/or clarity.
[0038] As used herein, "submersible" means an object that is
submersible in an intended liquid, such as water, and constructed
such that electronic and other components thereof sensitive to the
liquid are protected from contact with the surrounding liquid.
[0039] As used herein, "fin dihedral angle" refers to an angle
defined by a fin of a vehicle including a pair of opposed fins each
joined to a body of the vehicle at a fin root, each fin having a
fin tip opposite its fin root and defining a fin axis extending
from its fin root to its fin tip. The dihedral angle of the fin is
the angle defined between its fin axis and a reference plane,
wherein the reference plane extends through the fin root of each
fin and is parallel to a direction of travel of the vehicle
body.
[0040] When the fin tip is located above the reference plane, the
fin dihedral angle is referred to as "upward." When the fin tip is
located below the reference plane, the fin dihedral angle is
referred to as "downward."
[0041] The fin dihedral angle can also be characterized with
respect to the direction of force due to net buoyancy of the
vehicle. When the fin tip is located away from the reference plane
on a side of the reference plane opposite the direction of net
buoyancy of the vehicle, the fin dihedral angle is referred to as
"positive." When the fin tip is located away from the reference
plane on the same side of the reference plane as the direction of
net buoyancy of the vehicle, the fin dihedral angle is referred to
as "negative." Thus, when the fin dihedral angle is upward and the
net buoyancy is downward (i.e., the vehicle is sinking), the fin
dihedral angle is positive; when the fin dihedral angle is upward
and the net buoyancy is upward (i.e., the vehicle is rising), the
fin dihedral angle is negative; when the fin dihedral angle is
downward and the net buoyancy is upward (i.e., vehicle rising), the
fin dihedral angle is positive; and, when the fin dihedral angle is
downward and the net buoyancy is downward (i.e., vehicle sinking),
the fin dihedral angle is negative.
[0042] A fundamental impediment to conventional underwater glider
performance is the use of fins having zero dihedral angle. It is
well known that an upward, positive dihedral angle can enhance
performance in heavier than air (negatively buoyant) aircraft.
Aquatic gliders, however, glide both up and down according to their
buoyancy. During up gliding, a fixed upward dihedral angle would
act as an anhedral with adverse consequences. Current generation
aquatic gliders have fins fixed with a zero degree (i.e., neutral)
dihedral angle, sacrificing the enhancement of a non-zero dihedral
angle to avoid adverse anhedral angle affects.
[0043] In accordance with embodiments of the present invention, a
finned submersible vehicle (e.g., an aquatic vehicle) is provided
having provision for beneficially varying the dihedral angles of
its fins in order to overcome the above-described problems of
conventional submersible vehicles. According to methods of the
present invention, the dihedral angles of the fins are selectively
varied to improve performance during the up and/or down portions of
a glide cycle, which may be accomplished without substantially
compromising mission duration. According to some embodiments, the
fin dihedral angles are upward when the vehicle is descending and
downward when the vehicle is ascending. In this manner, the fin
dihedral angles provided are positive during both descent and
ascent.
[0044] With reference to FIGS. 1-5, a submersible vehicle (e.g., a
water submersible vehicle) 100 according to embodiments of the
present invention is shown therein in a body of water W (e.g., an
ocean, river or lake). According to some embodiments, the vehicle
100 is an unmanned underwater vehicle (UUV) or autonomous
underwater vehicle (AUV). According to some embodiments, the
vehicle 100 is an underwater glider. The vehicle 100 can be used
for sensing, payload carrying or deploying, object servicing, and
communicating in aquatic environments, for example. The vehicle 100
includes a vehicle body 102, a pair of opposed articulable fins
110, 112, a thrust system 103, a vehicle controller 107, and a
dihedral angle control system 120. The vehicle 100 may include
further components, systems or subcomponents such as a payload 105,
a recharging system, and/or a power supply (e.g., a battery).
[0045] The vehicle controller 107 controls the operation and
interoperation of the various modules and systems. The vehicle
controller 107 may include any suitable electronics (e.g., a
microprocessor), software and/or firmware configured to provide the
functionality described herein. While the controller 107 is
illustrated herein schematically as a single module, the vehicle
controller 107 may be functionally and physically distributed over
multiple devices or subsystems.
[0046] The payload 105 may be provided as a module and may include
components for vehicle guiding/navigating, sensing, communicating,
operating, causing, neutralizing, marking, material-providing,
and/or mass-altering, for example. In some cases, the payload 105
includes a deployable device, such as an acoustic communication
node or a sonar or other sensor array. In some cases, the
deployable device includes a receiver that can receive energy
and/or data conducted from the vehicle 100. In some cases, the
payload includes a payload battery and a payload memory for storing
products of receiving, and a receiver connector, which can be of
any type that can receive a submersible connector.
[0047] The payload 105 may include a communication system or module
(which may be part of or connected to the vehicle controller 107,
for example), which may include a radio, acoustic modem and/or
light emitting device, for example. In some cases, the
communication system or module includes a deployable portion such
as a releasable buoyant radio or antenna.
[0048] The payload 105 may include a sensing device or module
operative to sense one or more desired parameters, conditions
and/or events. For example, the sensing system or module may detect
an environmental parameter such as an attribute of the water (e.g.,
conductivity, temperature, depth, water current, turbulence,
luminescence, turbidity, presence or concentration of dissolved
oxygen, pH, or chlorophyll presence or concentration), or acoustic
noise.
[0049] The payload 105 may include a guidance module or system. The
guidance system may include a guidance system as disclosed in
Applicant's U.S. Published Patent Application No.
US-2008-0239874-A1, published on Oct. 2, 2008, titled "Underwater
Guidance Systems, Unmanned Underwater Vehicles and Methods," the
disclosure of which is incorporated herein by reference.
[0050] The thrust system 103 (FIG. 1) includes a hull 102A (forming
a part of the body 102), the fins 110, 112, and a buoyancy control
system 104 that cooperate to generate forward thrust (e.g., in a
forward direction +X as indicated in FIG. 4). In general, the
buoyancy control system 104 is operable to selectively change the
buoyancy of the vehicle body 102 and thereby generate a vertical
force that the shape of the hull 102A and/or the fins 110, 112
convert at least partly into displacement in the forward direction.
The hull 102A and/or the fins 110, 112 operate as force redirectors
and are configured such that they generate a forward glide thrust
responsive to changes in the elevation of the hull 110. In other
embodiments, the hull 102A or the fins 110, 112 do not serve as
force redirectors. According to some embodiments, the hull 102A
and/or the fins 110, 112 are configured to generate a forward glide
thrust both as the vehicle 100 rises and as the vehicle 100 drops
due to variations in the buoyancy of the body 102. Aspects of the
hull 102A and the buoyancy control system 104 will now be
described. However, other hull configurations and buoyancy control
mechanisms than those described and shown may be employed in some
embodiments of the present invention.
[0051] The hull 102A may be sized and shaped to provide a desired
lift and/or drag (which may be expressed as a lift/drag ratio
(LDR)). In some embodiments, the hull 102A is sized and shaped to
contain desired components and payload. The hull 102A is configured
such that, when the hull 102A is subjected to a vertical thrust in
the water W, the hull 102A will convert at least a portion of said
vertical thrust into forward thrust (i.e., in the direction +X).
That is, when a vertical flow of the water W is applied across the
hull 102A, the hull 102A will generate a reaction force that is
transverse to vertical (i.e., has a horizontal force vector).
[0052] In some embodiments, the hull 102A has a lift producing
shape, with "lift" defined as a force at least partly orthogonal to
the surface of the hull 102A, which force is generated by faster
movement of a fluid or gas over that surface, according to what is
commonly known as Bernoulli's principle. In some cases, the vehicle
100 includes one or more control surfaces such as a rudder or
vertical stabilizer. In some cases, the vehicle 100 can further
include a housing in which components can be mounted (e.g., a
sensor, a processor, an energy storage device, communications
electronics, and/or a payload or payload managing devices).
[0053] The buoyancy control system 104 includes a buoyancy engine,
which may include a gas generator, a reservoir, and one or more
outlets. The gas generator is operable to generate a displacement
gas to displace water from the reservoir to thereby lower the
density of the vehicle 100 and increase its buoyancy. In some
embodiments, the gas generator includes a mixer and a supply or
supplies of one or more gas generation substances that can generate
a gas when mixed with one another or with water. The gas generator
may additionally or instead include a converter unit that can
convert a liquid or gas at least partly into a gas, such as by
catalysis or by providing energy. The gas generator may
additionally or instead include a container containing a compressed
gas that can selectively release the gas. According to some
embodiments, the buoyancy control system 104 includes a buoyancy
control system as disclosed in U.S. patent application Ser. No.
12/315,760, filed Dec. 5, 2008 [Attorney Docket Number 5579-29],
the disclosure of which is incorporated herein by reference.
[0054] The fins 110, 112 may be formed of any suitable material and
in any suitable shape. For example, each fin 110, 112 may include a
thin, flat, substantially rigid or semi-rigid plate. In some
embodiments, the fins 110, 112 have a lift providing or generating
shape. In some embodiments, the fins 110, 110 are cambered in
section. In some cases, the fins 110, 112 are low drag.
[0055] Each fin 110, 112 has a respective fin tip 110A, 112A and a
respective fin root 110B, 112B. The fin 110 is pivotably joined to
the body 102 by a coupling 110C at the fin root 110B to rotate
about a pivot axis P1-P1. The fin 112 is pivotably joined to the
body 102 by a coupling 112C at the fin root 112B to rotate about a
pivot axis P2-P2. The fin 110 has a fin axis D1-D1 extending
through the fin tip 110A and the fin root 110B. The fin 112 has a
fin axis D2-D2 extending through the fin tip 112A and the fin root
112B.
[0056] With reference to FIGS. 1-3, the fin 110 forms a fin
dihedral angle A1 with a reference plane RP and the fin 112 forms a
dihedral angle A2 with the reference plane RP. The reference plane
RP extends parallel to the direction of travel T (FIG. 1) of the
vehicle when the vehicle is underway. Each of the fin roots 110B,
112B is in the reference plane RP. In some embodiments and as shown
in FIG. 2, the pivot axes P1-P1 and P2-P2 are parallel to the
reference plane RP. In some embodiments, the center line CL-CL of
the vehicle body 102 and the direction of travel T lie in the
reference plane RP. According to some embodiments, when the vehicle
100 is travelling in a true horizontal direction and the vehicle
buoyancy is non-zero, the reference plane RP is orthogonal to the
direction of net buoyancy.
[0057] The dihedral angle control system 120 varies the dihedral
angles A1, A2 of the fins 110, 112 as the vehicle transits through
the water W under the force of the thrust system 103. More
particularly, the orientation of each fin 110, 112 is varied
through a range of fin dihedral angles A1, A2 including, on some
occasions, an upward fin dihedral angle A1, A2 as show in FIG. 2
and, on some occasions, a downward fin dihedral angle A1, A2 as
shown in FIG. 3. In some embodiments, the system 120 passively
varies the dihedral angles A1, A2. In some embodiments, the system
120 fully or partly actively or forcibly varies the dihedral angles
A1, A2.
[0058] Operations of the vehicle 100 and the dihedral angle control
system 120 will now be described, followed by descriptions of more
particular embodiments of the invention.
[0059] Navigation or transit of the vehicle 100 can be provided by
the thrust system 103 which controllably propels the vehicle body
102. The thrust system 103 propels the vehicle 100 in the travel
direction T and generally in the forward direction +X by changing
the buoyancy of the vehicle 100. The buoyancy control system 104
may alter the buoyancy of the vehicle 100 by selectively generating
gas to purge water from the reservoir, releasing or purging gas
from the reservoir, and/or changing the capacity of the reservoir,
for example. In this manner, the buoyancy control system 104
generates a vertical force (up, if the buoyancy change is positive,
or down, if the buoyancy change is negative) on the vehicle
100.
[0060] As discussed above, the hull 102A may be configured to
convert at least a portion of said vertical force into forward
thrust (i.e., in the direction +X). In this manner, the vehicle 100
is propelled in a desired direction on a glide path with an angle
determined by the LDR of the hull 102A. In embodiments wherein the
hull 102A has a lift producing shape, the forward movement of the
hull 102A can generate a further lift force which can alter the
rate of change in depth. The buoyancy control system 104 can
repeatedly adjust the vehicle buoyancy (e.g., increasing and
decreasing the vehicle buoyancy) so that the vehicle 100 is
continuously propelled forward by the buoyancy control system 104
while remaining generally in a desired elevation range. In some
embodiments, the buoyancy control system 104 is operated to control
a net buoyancy of the vehicle in response to local water density to
maintain the vehicle 100 at neutral buoyancy when not being
employed to change the elevation of the vehicle 100 in the water
W.
[0061] Also, as discussed above, the fins 110, 112 may be
configured to convert at least a portion of said vertical force
into forward thrust (i.e., in the direction +X).
[0062] FIG. 4 illustrates operation of the thrust system 103
conveying the vehicle 100 through the water W and horizontally in
the forward direction +X. From a position L1, the buoyancy control
system 104 provides the vehicle 100 with a net positive buoyancy to
create an upward force vector. The hull 102A converts a portion of
the upward force vector to a horizontally directed gliding force
vector so that the vehicle 100 glides or transits upwardly and
forwardly to a second position L2. The buoyancy control system 104
then provides the vehicle 100 with a net negative buoyancy to
create a downward force vector. The hull 102A converts a portion of
the downward force vector to a horizontally directed gliding force
vector so that the vehicle 100 glides downwardly and forwardly to a
third position L3. The buoyancy control system 120 can again
increase the vehicle buoyancy to a net positive buoyancy to glide
the vehicle 100 upwardly and forwardly to a fourth position and so
forth. While the vehicle 100 is illustrated as traveling in a
generally sinusoidal path, other travel paths may be provided.
[0063] As discussed above, the dihedral angle control system 120
causes or enables the fins 110, 112 to rotate about their couplings
110C, 112C to vary their respective dihedral angles A1, A2. As the
vehicle 100 ascends (i.e., in the vertical direction +Y) with a net
positive buoyancy ("up glide"), the fins 110, 112 rotate into
positions as shown in FIG. 3 and in FIG. 4 at position L1 wherein
the dihedral angles A1, A2 are downward. As the vehicle 100
descends (i.e., in the vertical direction -Y) with a net negative
buoyancy ("down glide"), the fins 110, 112 rotate into positions as
shown in FIGS. 1 and 2 and in FIG. 4 at position L2 wherein the
dihedral angles A1, A2 are upward. According to some embodiments,
the dihedral angles A1, A2 may instead be substantially zero when
ascending or when descending.
[0064] In this manner, the dihedral angles A1, A2 can be maintained
opposite the direction of net buoyancy and the vertical component
of vehicle travel. That is, the dihedral angle is downward when net
buoyancy is positive and upward when the net buoyancy is negative.
Dynamically varying the dihedral angles A1, A2 in this manner can
provide the beneficial effects of positive, non-zero fin dihedral
angle (i.e., a dihedral angle opposite the direction of net
buoyancy) in one or both directions of travel (ascending and
descending) without presenting the undesirable effects that would
accompany having a negative dihedral angle (i.e., a dihedral angle
in the same direction as net buoyancy) when descending or
ascending.
[0065] As shown in FIGS. 1-4, the dihedral angles A1, A2 of the
fins 110, 112 may be maintained substantially the same to enable or
facilitate travel of the vehicle 100 in a horizontally straight
direction. In some cases, the dihedral angles A1, A2 may be
independently controlled so that they differ from one another to
induce a turning, pitching or rolling moment on the vehicle 100.
For example, according to some embodiments and as illustrated in
FIG. 5 (depicting the vehicle 100 with a negative buoyancy), the
fin 110 can be positioned with an upward dihedral angle A1 while
the fin 112 is positioned with a downward dihedral angle to direct
the vehicle 100 into a banking turn.
[0066] According to some embodiments, the dihedral angle A1, A2 of
each fin 110, 112 can be varied across a range of at least about 50
degrees and, according to some embodiments, a range of from at
least about +25 to at least about -25 degrees. According to some
embodiments, the dihedral angle A1, A2 of each fin 110, 112 can be
varied across a range of at least about 90 degrees and, according
to some embodiments, a range of from at least about +45 to at least
about -45 degrees.
[0067] The vehicle control system 107 can include a guidance
navigation and control (GNC) sensor, a state sensor, an
environmental sensor, and/or a processor. In some cases, the
vehicle control system 107 system can further comprise a
communications system of any type such as radio, acoustic, or
optical. The GNC sensor may include a depth, altitude, speed,
inclination, acceleration, roll, direction, location, inertial
measurement, homing, and/or obstacle avoidance sensor. The state
sensor may include a buffeting, stall, vibration, pressure, leak,
power, and/or system health sensor. The environmental sensor can be
a temperature, conductivity, pressure, depth, acoustic, electric,
electromagnetic, optical, bioluminescence and/or fluorescence
sensor, for example. The processor can be any type that can process
sensor signals and provide control signals to the dihedral angle
control system 120, the buoyancy control system 104, the
communications system, and/or a battery system.
[0068] The dihedral angle control system 120 can be used to change
the dihedral angles A1, A2 (together or independently), stabilize
the dihedral angles A1, A2, maneuver the vehicle 100, and/or modify
the performance characteristics of the vehicle 100. Maneuvering can
include transiting, turning, rising falling, rolling pitching,
yawing, angle of attack changing, inclination changing, direction
controlling, buffeting responding, and/or stabilizing. In some
cases, maneuvering can be responsive to speed, depth, direction,
and/or changes therein.
[0069] In some cases, dihedral angle change is provided passively
by lift force during gliding, which pursuant to change in buoyancy
can move the fin up or down. The dihedral angle control system 120
may be configured to limit the maximum obtainable upward or
downward dihedral angles A1, A2 (e.g., using stops as discussed
herein).
[0070] The dihedral angle control system 120 can operate passively
(e.g., relying on lift force alone to change the dihedral angles
A1, A2) or actively (i.e., using one or more force actuators to
force a change in the dihedral angles A1, A2). Where active control
is employed, the dihedral angle control system 120 may control the
dihedral angles A1, A2 as a function of one or more selected
parameters intrinsic or extrinsic to the vehicle 100.
[0071] The dihedral angle control system 120 may be used to provide
a force responsive to buoyancy force or to intermittent forces such
as buffeting. The dihedral angle control system 120 may control the
dihedral angles A1, A2 responsive to navigation sensor signals,
state sensor signals, and/or an intended navigational course. In
some cases, the dihedral angle control system 120 processes signals
representative of at least one of force on the vehicle, moment on
the vehicle, vehicle speed, vehicle direction, vehicle inclination,
vehicle rotation, vehicle depth, water temperature, water salinity,
vehicle location, and predetermined operational parameters, and
responsively provides control signals to one or more force
actuators that in turn correspondingly adjust the dihedral angles
A1 and/or A2. In some cases, the dihedral angle control system 120
provides a first control signal to a first force actuator operative
to change the dihedral angle A1 and a second control signal to a
second force actuator operative to change the dihedral angle A2 for
purposes of steering, glide changing, depth changing, and/or
stabilizing the vehicle 100. In some cases, the dihedral angle
control system 120 provides a signal to at least one dihedral
actuator as means of augmenting rate and/or magnitude of change in
dihedral angle (e.g., responsive to change in net buoyancy). In
some cases, this is used to speed transition between up glide and
down glide.
[0072] Systems, components, mechanisms and configurations for
enabling and effecting the foregoing operations and methods are
described hereinafter with reference to FIGS. 6-12. However, the
embodiments described are not exhaustive of vehicles according to
embodiments of the present invention or suitable apparatus for
enabling operations and methods according to embodiments of the
present invention.
[0073] With reference to FIG. 6, a right-side portion of a vehicle
200 according to embodiments of the present invention is shown
therein, viewed from the front of the vehicle 200. The vehicle 200
corresponds to the vehicle 100 and has a fin 210 corresponding to
the wing 110 and a dihedral angle control system 220 corresponding
to the dihedral angle control system 120. The fin 210 is joined to
the body 202 by a coupling 210C at its fin root 210B to permit the
fin 210 to pivot as described above to vary the dihedral angle A1.
In some embodiments, the coupling 210C is a hinge. However, any
suitable coupling that can permit dihedral angle change, such as by
rotation, deformation and/or translation, may be used.
[0074] The dihedral angle control system 220 includes an upper stop
230 and a lower stop 232. The fin 210 may be free to rotate about
the coupling 210C within the limits imposed by the stops 230, 232.
The fin 210 is thereby enabled to change the dihedral angle A1 as
discussed above to beneficially match the vertical direction of
glide. The change in dihedral angle may be induced by lift force or
any other force acting on the fin 210. In FIG. 6, the maximum
upward dihedral angle position for the fin 210 is shown in solid
line and the maximum downward dihedral angle position for the fin
210 is shown in dashed line. The positions of the stops 230, 232
may be selected as a function of lift-drag ratio, lift force, drag
force, center of gravity, center of lift, center of buoyancy, hull
shape, trim, and/or balance. In some embodiments, the stops
230.sub.; 232 are situated asymmetrically with respect to the
centerline CL-CL and/or with respect to the reference plane RP. The
vehicle 200 also has a fin corresponding to the fin 112 and the
dihedral angle control system 220 includes stops and a coupling
(not shown) corresponding to the stops 230, 232 and coupling 210C
on the opposite side of the body 202 to permit and regulate
variation of the dihedral angle A2. The dihedral angle control
system 220 may be regarded as a passive system (i.e., no actuator
is employed to directly vary the dihedral angles of the fins).
[0075] According to some embodiments, one or more of the stops 230,
232 may be position adjustable in order to change the endpoints
and/or ranges of permitted dihedral angles. The stops 230, 232 may
be manually adjustable and/or adjustable via one or more actuators
(e.g., connected to the vehicle controller 107 or another suitable
controller).
[0076] With reference to FIG. 7, a right-side portion of a vehicle
300 according to embodiments of the present invention is shown
therein, viewed from the front of the vehicle 300. The vehicle 300
corresponds to the vehicle 200 and has a fin 310 corresponding to
the fin 210 and a dihedral angle control system 320 corresponding
to the dihedral angle control system 220 except as follows. The
dihedral angle control system 320 further includes respective
magnets 330A, 332A mounted on (e.g., embedded in) each stop 330,
332 and a magnetically attractable portion 310D of the fin 310,
which collectively form a passive magnetic actuator. The magnets
330A, 332A and the magnetically attractable portion 310D may be
permanent magnets, for example. The magnet 330A is oriented to
attract the upper portion of the portion 310D and the magnet 332A
is oriented to attract the lower portion of the portion 310D. In
use, the magnets 330A, 332A and portion 310D serve to releasably
urge the fin 310 toward the nearer of the stops 330, 332 to
stabilize the fin 310 and/or to accelerate the transition to a new
dihedral angle. The stabilizing force may serve to resist
buffeting, for example. The vehicle 300 also has a fin
corresponding to the fin 112 and the dihedral angle control system
320 includes components (not shown) corresponding to the components
330, 332, 330A, 332A, 310D on the opposite side of the body 302 to
permit and regulate variation of the dihedral angle A2.
[0077] The strengths of the magnets 330A, 332A (and 310A, if a
magnet) may be selected to accommodate the anticipated fin lift
force and other parameters. For example, the attraction may be
strong enough to stabilize the fin 310 during up and down glide but
not so strong as to prevent dihedral angle change pursuant to a
change in the direction of net buoyancy.
[0078] In some cases, the dihedral angle control system 320 further
includes a reversible interlock that can mechanically engage the
fin 310 to hold the fin 310 proximate the stops 330A, 332A.
[0079] With reference to FIG. 8, a right-side portion of a vehicle
400 according to embodiments of the present invention is shown
therein, viewed from the front of the vehicle 400. The vehicle 400
corresponds to the vehicle 300 and has a fin 410 corresponding to
the fin 310 and a dihedral angle control system 420 corresponding
to the dihedral angle control system 320 except as follows. The
magnets 430A, 432A of the dihedral angle control system 420 mounted
in the stops 430, 432 are electromagnets. The dihedral angle
control system 420 further includes a magnet controller 440
electrically coupled to the magnets 430A, 432A by connections 440A.
The magnet controller 440 may selectively activate or deactivate
each of the electromagnets 430A, 432A to magnetically pull the
attractable fin portion 410D toward a selected one of the stops
430, 432 and/or to magnetically push the attractable fin portion
410D away from a selected one of the stops 430, 432. The vehicle
400 likewise has a fin (now shown) corresponding to the fin 112
opposite the fin 410 and regulated by electromagnets as described
for the fin 410.
[0080] With reference to FIG. 9, a right-side portion of a vehicle
500 according to embodiments of the present invention is shown
therein, viewed from the front of the vehicle 500. The vehicle 500
corresponds to the vehicle 200 and has a fin 510 corresponding to
the fin 210 and a dihedral angle control system 520 corresponding
to the dihedral angle control system 220 except as follows. The
dihedral angle control system 320 further includes an elastically
deformable biasing member 544 having a plurality of alternative
stable configurations. The biasing member 544 urges the fin 510
toward one of two different fin positions depending on the position
of the fin 510 and/or other conditions.
[0081] In some embodiments, the biasing member 544 is a spring. In
some embodiments, the biasing member 544 has a maximum force at
zero dihedral angle and a minimum force at prescribed positive
and/or negative dihedral angles other than zero. According to some
embodiments, the maximum force of the biasing member 544 is less
than a prescribed lift force in order to enable the fin 510 to
transition between upward and downward dihedral angles responsive
to change in the direction of lift force.
[0082] In some embodiments, the biasing member 544 is a bi-stable
spring configured such that the biasing member 544 forces the fin
510 toward the upper stop 530 when the dihedral angle A1 is greater
than a prescribed upward dihedral angle and forces the fin 510
toward the lower stop 532 when the dihedral angle A1 is greater
than a prescribed downward dihedral angle.
[0083] In some embodiments, the biasing member 544 is a deformable
member including a memory metal. An electrical power controller 545
selectively applies electrical current to the memory metal to
induce the biasing member 544 to alternately assume each of its
stable configurations depending on the position of the fin 510
and/or other conditions. The electrical power controller 545 may be
networked with the vehicle controller 107 so that the vehicle
controller 107 can control the biasing member 544 according to
other factors generated or sensed by the vehicle controller
107.
[0084] The vehicle 500 also has a fin corresponding to the fin 112
and the dihedral angle control system 520 includes a biasing member
(not shown) corresponding to the biasing member 544 on the opposite
side of the body 502 to permit and regulate variation of the
dihedral angle A2.
[0085] With reference to FIG. 10, a right-side portion of a vehicle
600 according to embodiments of the present invention is shown
therein, viewed from the front of the vehicle 600. The vehicle 600
corresponds to the vehicle 200 and has a fin 610 corresponding to
the fin 210 and a dihedral angle control system. 620 corresponding
to the dihedral angle control system 220 except as follows. The
dihedral angle control system 620 includes upper and lower stops
630, 632 and a force actuator system 650. The force actuator system
650 includes a force actuator 654, an actuator controller 656, and
a couple 658 operatively connecting the actuator 654 to the fin
610. A mount 652, such as a low drag shell, may house and secure
some or all of the force actuator system 650 to the body 602. In
use, the actuator controller 656 actuates the actuator 654 to force
the fin 610 to pivot in either direction to actively change the
dihedral angle A1 of the fin 610. The actuator controller 656 may
be networked with the vehicle controller 107 so that the vehicle
controller 107 can control the biasing member 544 according to
other factors generated or sensed by the vehicle controller 107.
According to some embodiments, the force actuators associated with
the left and right side fins are independently controllable to
actively position the fins at different dihedral angles A1, A2 from
one another as disclosed above with regard to FIG. 5.
[0086] Suitable types of active actuators for the actuator 654 may
include a linear motor (as illustrated; e.g., as sold by Balder
Electric Company of Fort Smith, Ark.), a stepper motor (e.g., as
sold by Shinano Kenshi Corp. of Culver City, Calif.), a solenoid
(e.g., as sold by Magnetic Sensor Systems of Van Nuys, Calif.), a
Lorenz force motor, or a flooded actuator as disclosed in
co-pending U.S. patent application Ser. No. 12/348,956, [Attorney
Docket No. 5579-34], the disclosure of which is incorporated herein
by reference. According to some embodiments, the actuator 654 is
operable to provide a continuously variable dihedral angle A1.
According to some embodiments, the force actuator is a rotational
actuator or stepper motor comprising a portion of the fin root.
[0087] With reference to FIG. 11, a vehicle 700 according to
further embodiments of the present invention is shown therein. The
vehicle 700 includes opposed fins 710, 712 and corresponds to the
vehicle 100 except that the vehicle further includes an active
propulsion system 760 in addition to or in place of the buoyancy
control system 104. The active propulsion system 760 includes a
propeller 764 and a motor 762. The active propulsion system 760 may
be used to drive the vehicle 700 forward and, in some cases, to
steer the vehicle 700. The vehicle 700 may incorporate any of the
features or aspects discussed herein with regard to the vehicles
100, 200, 300, 400, 500, 600. For example, the dihedral angle
control system 720 of the vehicle 700 may be configured as
discussed herein with respect to any of the dihedral angle control
systems 120, 220, 320, 420, 520, 620.
[0088] With reference to FIG. 12, a glider system 801 according to
further embodiments of the present invention is shown therein. The
glider system 801 includes a submersible vehicle 800 and a tow
vehicle 870. The vehicle 800 includes opposed fins 810, 812 and a
dihedral angle control system 820. The vehicle 800 is joined to and
towed by the tow vehicle 870 via a tether 872. The vehicle 800 may
incorporate any of the features or aspects discussed herein with
regard to the vehicles 100, 200, 300, 400, 500, 600. For example,
the dihedral angle control system 820 of the vehicle 800 may be
configured as discussed herein with respect to any of the dihedral
angle control systems 120, 220, 320, 420, 520, 620.
[0089] According to some methods, the dihedral angle of one of the
opposed fins is held steady (e.g., using an active control
mechanism as described with reference to FIG. 8 or FIG. 10) while
the dihedral angle of the other fin is permitted or caused to
transition or switch as the vertical component of vehicle travel
flips (i.e., the vehicle changes from ascending to descending or
vice-versa). This method may cause the vehicle to execute an
enhanced turn at the very beginning of an up or down glide of the
vehicle.
[0090] Submersible vehicles (e.g., aquatic gliders), dihedral angle
control systems and methods as disclosed herein can provide
enhanced operational capabilities. Gliders and actuators are
provided that permit and/or provide change in fin dihedral angle
between the up glide and down glide portions of a glide cycle to
provide a fin dihedral angle that is positive during both the down
and up glide portions. The dihedral angle control system can
thereby provide enhanced performance in terms of maneuverability,
stability, and/or energy efficiency. The dihedral angle control
system may also provide differential control of actuators on
contra-lateral fins to provide enhanced maneuverability of the
vehicle.
[0091] The vehicle 100 can be used to carry a payload to a desired
location. The vehicle 100 can carry one or more sensors for
operations. An illustrative payload includes one or more sensors or
a sensing array. In some cases, the sensor and/or array is
deployable. A second illustrative payload includes a neutralization
charge. A third illustrative payload is materiel for personnel. A
fourth illustrative payload is a releasable device for
communicating from proximate the water surface. A fifth
illustrative includes a marker that can provide a signal, such as
for navigation aiding and/or communicating.
[0092] The vehicle 100 can be navigated to establish an operating
position, and may be further navigated to establish a second,
subsequent operating position. In some cases, the operating
position is established by settling on or, at least partly, in
sediment.
[0093] The vehicle 100 may be used to conduct surveillance and/or
survey in the operational area. In some cases, the vehicle 100
detects signals and/or images, water parameters, and/or events. In
some cases, the vehicle 100 communicates responsive to detecting.
In some cases, the vehicle 100 deposits and/or releases a payload.
In some cases, the vehicle 100 operates or monitors a deposited or
deployed payload. In some cases, the vehicle 100 recovers an
object. In some cases, the vehicle 100 interchanges energy and/or
data with a secondary object. One example is providing energy
and/or data to a secondary object. In another example, the vehicle
100 retrieves data from a secondary object. In some embodiments,
the secondary object includes a sensing system deployed in the
substratum. In some embodiments, the secondary object includes
another vehicle.
[0094] The sensor device may be used to determine a location of the
vehicle 100 such as by GPS or compass reading. In some cases, the
sensor device detects signals and/or water parameters. In some
eases, signal detection by the sensor device includes processing
signals and/or parameters according to an algorithm. In some cases,
the sensor device senses signals (e.g., acoustic, optical,
electrical, or magnetic) indicative of a desirably sensed
construction. In some cases, the sensor device determines an
environmental potential (e.g., redox potential) of sediment. In
some cases, the sensor device infers a location of the vehicle
(e.g., from signals of opportunity). The results of detecting may
be processed to classify a signal and/or its source or to provide a
derived parameter such as a sound velocity, a water current profile
and or a water salinity profile, for example.
[0095] In some embodiments, at least a portion of a communications
device is deployed to communicate. The communications module may
send data reflective of location and/or results of processing. In
some cases, the vehicle releases an expendable communication
devices such as disclosed in co-assigned U.S. patent application
Ser. Nos. 11/494,941 and 11/495,134, the disclosures of which are
incorporated herein by reference. In some cases, the communications
device uses a radio and/or an optical or acoustic transponder. In
some cases, the communications device receives signals such as
commands, algorithm updates, or operational data.
[0096] The foregoing is illustrative of the present invention and
is not to be construed as limiting thereof. Although a few
exemplary embodiments of this invention have been described, those
skilled in the art will readily appreciate that many modifications
are possible in the exemplary embodiments without materially
departing from the novel teachings and advantages of this
invention. Accordingly, all such modifications are intended to be
included within the scope of this invention as defined in the
claims. In the claims, means-plus-function clauses are intended to
cover the structures described herein as performing the recited
function and not only structural equivalents but also equivalent
structures. Therefore, it is to be understood that the foregoing is
illustrative of the present invention and is not to be construed as
limited to the specific embodiments disclosed, and that
modifications to the disclosed embodiments, as well as other
embodiments, are intended to be included within the scope of the
appended claims. The invention is defined by the following claims,
with equivalents of the claims to be included therein.
* * * * *