U.S. patent application number 16/052938 was filed with the patent office on 2019-11-21 for modular aircraft assembly for airborne and ground transport.
The applicant listed for this patent is SUNLIGHT AEROSPACE INC.. Invention is credited to MICHAEL CYRUS, SERGEY V. FROLOV, JOHN PETER MOUSSOURIS.
Application Number | 20190352004 16/052938 |
Document ID | / |
Family ID | 64562568 |
Filed Date | 2019-11-21 |
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United States Patent
Application |
20190352004 |
Kind Code |
A9 |
FROLOV; SERGEY V. ; et
al. |
November 21, 2019 |
MODULAR AIRCRAFT ASSEMBLY FOR AIRBORNE AND GROUND TRANSPORT
Abstract
An aircraft for vertical take-off and landing includes an
aircraft frame having an open frame portion, at least one vertical
thruster, a pod, separable from the aircraft and including a cabin
to contain at least one of cargo and passengers, where the pod,
when mounted to the aircraft, defines at least a portion of the
aircraft frame, and a mounting system including at least one
attachment member configured to attach the pod to the open frame
portion. Such aircraft is capable of flight with and without the
pod.
Inventors: |
FROLOV; SERGEY V.; (New
Providence, NJ) ; CYRUS; MICHAEL; (Castle Rock,
CO) ; MOUSSOURIS; JOHN PETER; (Palo Alto,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SUNLIGHT AEROSPACE INC. |
Edison |
NJ |
US |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20180354617 A1 |
December 13, 2018 |
|
|
Family ID: |
64562568 |
Appl. No.: |
16/052938 |
Filed: |
August 2, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15620178 |
Jun 12, 2017 |
10040553 |
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16052938 |
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15252297 |
Aug 31, 2016 |
9714090 |
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15620178 |
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14737814 |
Jun 12, 2015 |
9541924 |
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15252297 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B64C 17/08 20130101;
B64C 17/02 20130101; B64C 29/0058 20130101; B64C 39/10 20130101;
B60F 5/02 20130101; B64C 2211/00 20130101; G05D 1/0088 20130101;
B64C 39/02 20130101; B64C 37/00 20130101; B64C 29/0025
20130101 |
International
Class: |
B64C 37/00 20060101
B64C037/00; B60F 5/02 20060101 B60F005/02; B64C 29/00 20060101
B64C029/00; B64C 17/02 20060101 B64C017/02; B64C 17/08 20060101
B64C017/08; G05D 1/00 20060101 G05D001/00 |
Claims
1. An aircraft for vertical take-off and landing, comprising: an
aircraft frame comprising an open frame portion; at least one
vertical thruster; a pod, separable from the aircraft and including
a cabin to contain at least one of cargo and passengers, wherein
the pod, when mounted to the aircraft, defines at least a portion
of the aircraft frame; and a mounting system including at least one
attachment member configured to attach the pod to the open frame
portion; wherein the aircraft is capable of flight with and without
the pod.
2. The aircraft of claim 1, wherein the aircraft frame comprises a
wing providing a lift force during a horizontal flight.
3. The aircraft of claim 2, wherein the mounting system is a part
of the wing.
4. The aircraft of claim 1, further comprising a horizontal
thruster.
5. The aircraft of claim 1, wherein the pod, when mounted to the
aircraft, adds to the aerodynamic properties of the aircraft during
flight.
6. The aircraft of claim 1, wherein the at least one attachment
member is a part of at least one of the pod or the aircraft
frame.
7. The aircraft of claim 1, wherein the pod comprises multiple
pods.
8. The aircraft of claim 1, wherein the pod comprises means for
ground transportation.
9. The aircraft of claim 8, wherein the means for ground
transportation is separable from the pod.
10. The aircraft of claim 8, wherein the means for ground
transportation comprises wheels and a powertrain.
11. The aircraft of claim 8, wherein the means for ground
transportation is an autonomously controlled system.
12. The aircraft of claim 1, wherein the at least one attachment
member of the mounting system provides structural support to the
aircraft frame when the pod is detached.
13. The aircraft of claim 1, wherein the mounting system comprises
at least one of mounting locks, latches, braces or clamps for
mounting the pod to the aircraft.
14. The aircraft of claim 1, wherein the mounting system comprises
a movable attachment member to facilitate the attachment and
detachment of the pod.
15. The aircraft of claim 1, further comprising a tail, wherein the
mounting system is a part of the tail.
16. The aircraft of claim 1, wherein the aircraft frame comprises a
fuselage portion.
17. The aircraft of claim 16, wherein the fuselage portion is
segmented into a plurality of sections each containing a respective
mounting system.
18. The aircraft of claim 1, wherein the at least one attachment
member comprises a shape similar to an outer frame of the pod.
19. The aircraft of claim 1, further comprising a system to control
a location of a center of gravity of the aircraft.
20. The aircraft of claim 19, wherein the system to control a
location of a center of gravity is used during at least one of
loading the pod, unloading the pod, or a transition between
vertical and horizontal flight modes of the aircraft
21. The aircraft of claim 19, wherein the system to control a
location of a center of gravity includes fluid containers, fluid
transfer pipes and a pump.
22. The aircraft of claim 19, wherein the system to control a
location of a center of gravity includes ballast weights and an
adjustable suspension system.
23. The aircraft of claim 1, further comprising a flight control
system to provide at least one of remote and autonomous flight
control capabilities for the aircraft.
24. The aircraft of claim 23, wherein the flight control system is
configured to autonomously control a process for at least one of
mounting or dismounting the pod from the aircraft.
25. An aircraft, comprising: a wing portion providing a lift force
during a horizontal flight; at least one horizontal thruster; a
modular fuselage, comprising: a pod, separable from the aircraft
and including a cabin to contain at least one of cargo and
passengers, wherein the pod, when mounted to the aircraft, defines
at least a portion of an outer frame of the aircraft; and a
mounting system including an open frame portion in the frame of the
aircraft and at least one attachment member configured to attach
the pod to the open frame portion in the aircraft frame; wherein
the aircraft is capable of flight with and without the pod.
26. The aircraft of claim 25, further comprising at least one of a
vertical thruster for providing a lift force for vertical take-off
and landing or landing gear.
27. The aircraft of claim 25, further comprising a ground transport
system for the pod, wherein the ground transport system comprises
wheels and a powertrain.
28. The aircraft of claim 25, wherein the pod has a shape that when
mounted to the aircraft forms a continuous outer surface with at
least one of the wing portion or the modular fuselage.
29. An aircraft for vertical take-off and landing, comprising: an
aircraft frame; at least one vertical thruster; a pod, separable
from the aircraft and including a cabin to contain at least one of
cargo and passengers, wherein the pod, when mounted to the aircraft
defines at least an outer portion of the frame of the aircraft; and
a mounting system including at least one attachment member
configured to attach the pod to the aircraft frame; wherein the
aircraft is capable of flight with and without the pod.
30. The aircraft of claim 29, further comprising a ground transport
system for the pod, wherein the ground transport system comprises
wheels and a powertrain.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a
continuation-in-part of co-pending U.S. patent application Ser. No.
15/620,178, filed on Jun. 12, 2017, entitled, "VERTICAL TAKE-OFF
AND LANDING DETACHABLE CARRIER AND SYSTEM FOR AIRBORNE AND GROUND
TRANSPORTATION", which is a continuation of U.S. Pat. No.
9,714,090, issued Jul. 25, 2017, entitled "AIRCRAFT FOR VERTICAL
TAKE-OFF AND LANDING", which is continuation-in-part of U.S. Pat.
No. 9,541,924, issued Jan. 10, 2017, entitled "METHODS AND
APPARATUS FOR DISTRIBUTED AIRBORNE TRANSPORTATION SYSTEM", which
are all herein incorporated by reference in their entirety.
FIELD
[0002] Embodiments of the present invention generally relate to an
aircraft and methods for vertical take-off and landing (VTOL) for
application in at least airborne transportation and other
applications, and in particular to those for enabling massively
scalable modular transportation of passengers and cargo based on
vertical take-off and landing of airborne vehicles.
BACKGROUND
[0003] Modern airborne transportation is primarily based on large
size fixed-wing aircraft that can transport relatively large number
of passengers and amount of cargo between a limited number of
airports, which are areas specially created for take-off and
landing of regular aircraft. As a result, such a transportation
system is limited in its abilities to remain economical and provide
adequate services under increasing demands for faster, better and
more reliable performance. Airports represent one of the most
apparent bottlenecks in this system. They are expensive to operate
for owners and inconvenient to use for customers. Existing airports
are being utilized at close to capacity and additional ones are not
built fast enough.
[0004] Existing airborne transportation systems are in many ways
similar to ground-based centralized systems for public and mass
transportation, well-known examples of which are ones based on
railroad and highway bus transport. Such systems lack the
flexibility and convenience of a distributed transportation system,
such as for example a taxicab transportation service.
[0005] Therefore, the inventors have provided an improved airborne
transportation system, which provides one or more benefits of
distributed transportation.
SUMMARY
[0006] Embodiments of the present invention generally relate to an
aircraft for vertical take-off and landing.
[0007] In some embodiments, an aircraft for vertical take-off and
landing includes an aircraft frame having an open frame portion, at
least one vertical thruster, a pod, separable from the aircraft and
including a cabin to contain at least one of cargo and passengers,
where the pod, when mounted to the aircraft, defines at least a
portion of the aircraft frame, and a mounting system including at
least one attachment member configured to attach the pod to the
open frame portion. Such aircraft is capable of flight with and
without the pod.
[0008] In some embodiments of the present invention, an aircraft
for vertical take-off and landing includes at least one first wing
portion providing a lift force during a horizontal flight, at least
one vertical thruster, at least one horizontal thruster, and a
modular fuselage. In some embodiments, the modular fuselage
includes a pod, separable from the aircraft and including a cabin
to contain at least one of cargo and passengers, where the pod,
when mounted to the aircraft defines at least a portion of an outer
frame of the aircraft, and a mounting system including an open
frame portion in the frame of the aircraft and at least one
attachment member configured to attach the pod to the open frame
portion in the aircraft frame. In such embodiments, the aircraft is
capable of flight with and without the pod.
[0009] In some embodiments of the present invention, an aircraft
includes a wing portion providing a lift force during a horizontal
flight, at least one horizontal thruster, and a modular fuselage.
In some embodiments the modular fuselage includes a pod, separable
from the aircraft and including a cabin to contain at least one of
cargo and passengers, where the pod, when mounted to the aircraft,
defines at least a portion of an outer frame of the aircraft and a
mounting system including an open frame portion in the frame of the
aircraft and at least one attachment member configured to attach
the pod to the open frame portion in the aircraft frame. In such
embodiments, the aircraft is capable of flight with and without the
pod.
[0010] In some embodiments of the present invention, an aircraft
for vertical take-off and landing includes at least one first wing
portion providing a lift force during a horizontal flight, at least
one horizontal thruster, at least one vertical thruster, and a
modular fuselage. In some embodiments the modular fuselage includes
a pod, separable from the aircraft and including a cabin to contain
at least one of cargo and passengers and a ground transport system
including wheels and a powertrain, where the pod, when mounted to
the aircraft defines at least a portion of an outer frame of the
aircraft, and a mounting system including an open frame portion in
the frame of the aircraft and at least one attachment member
configured to attach the pod to the open frame portion in the
aircraft frame. In such embodiments, the aircraft is capable of
flight with and without the pod.
[0011] In some embodiments, an aircraft for vertical take-off and
landing, includes an aircraft frame, at least one vertical
thruster, a pod, separable from the aircraft and including a cabin
to contain at least one of cargo and passengers, where the pod,
when mounted to the aircraft defines at least an outer portion of
the frame of the aircraft, and a mounting system including at least
one attachment member configured to attach the pod to the aircraft
frame. In such embodiments, the aircraft is capable of flight with
and without the pod.
[0012] In some embodiments, a pod, when mounted to an aircraft,
such as an aircraft in accordance with one or all of the
embodiments described above, adds to the aerodynamic properties of
the aircraft during flight. In addition, in aircraft in accordance
with some or all of the embodiments described above, the pod can
include a ground transportation means.
[0013] In some embodiments, an aircraft, such as an aircraft in
accordance with one or all of the embodiments described above, can
include a tail section and the mounting system can be a part of the
tail section.
[0014] In some embodiments, an aircraft, such as an aircraft in
accordance with one or all of the embodiments described above, can
include a system to control a location of a center of gravity of
the aircraft
[0015] Other and further embodiments of the present invention are
described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Embodiments of the present invention, briefly summarized
above and discussed in greater detail below, can be understood by
reference to the illustrative embodiments of the invention depicted
in the appended drawings. It is to be noted, however, that the
appended drawings illustrate only typical embodiments of this
invention and are therefore not to be considered limiting of its
scope, for the invention may admit to other equally effective
embodiments.
[0017] FIG. 1 shows an airborne system for distributed
transportation of passengers and cargo in accordance with at least
some embodiments of the present invention.
[0018] FIG. 2 shows an exemplary fixed-wing aircraft with vertical
take-off and landing (VTOL) capabilities in accordance with at
least some embodiments of the present invention.
[0019] FIG. 3 shows an exemplary fixed-wing aircraft with vertical
take-off and landing (VTOL) capabilities having shuttered fan
openings in a VTOL vehicle configuration in accordance with at
least some embodiments of the present invention.
[0020] FIG. 4 shows a VTOL design in which the propulsion is
provided by two ducted fans in accordance with at least some
embodiments of the present invention.
[0021] FIG. 5 shows an exemplary method for providing distributed
airborne transportation services in accordance with at least some
embodiments of the present invention.
[0022] FIG. 6 shows schematically an example of a loading method in
accordance with at least some embodiments of the present
invention.
[0023] FIG. 7 shows schematically an example of a travel method in
accordance with at least some embodiments of the present
invention.
[0024] FIG. 8 shows schematically an example of a loading method in
accordance with at least some embodiments of the present
invention.
[0025] FIG. 9 shows examples of several fleet configurations in
accordance with at least some embodiments of the present
invention.
[0026] FIG. 10 shows schematically an example of a portion of a
travel method in accordance with at least some embodiments of the
present invention.
[0027] FIG. 11 shows a distributed transportation system in
accordance with at least some embodiments of the present
invention.
[0028] FIG. 12 shows a distributed transportation system in
accordance with at least some embodiments of the present
invention.
[0029] FIG. 13 shows a top view of a distributed transportation
system in accordance with at least some embodiments of the present
invention.
[0030] FIG. 14 shows a functional block diagram of an aircraft in
accordance with an embodiment of the present invention.
[0031] FIG. 15 shows a high level diagram of a wing assembly in
accordance with an embodiment of the present invention.
[0032] FIG. 16 shows a high level diagram of a wing assembly in
accordance with another embodiment of the present invention.
[0033] FIG. 17 shows a free-standing shaft-less propeller assembly
in accordance with an embodiment of the present invention.
[0034] FIG. 18 shows a cross-sectional diagram of an exemplary
mounting approach for shaft-driven propellers, such as the
propellers of FIG. 15 in accordance with an embodiment of the
present invention.
[0035] FIG. 19 shows a cross-sectional diagram of an exemplary
mounting approach for rim-driven propellers, such as the propellers
of FIG. 16 in accordance with an embodiment of the present
invention.
[0036] FIG. 20 shows a high level, cross-sectional diagram of a
portion of a wing assembly in accordance with another embodiment of
the present invention.
[0037] FIG. 21 shows a high level, top view diagram of a portion of
a wing assembly, such as the wing assembly of FIG. 20, in
accordance with an embodiment of the present invention.
[0038] FIG. 22 shows a high level, top view diagram of a portion of
a wing assembly in accordance with another embodiment of the
present invention.
[0039] FIG. 23 shows a high level, top view diagram of a portion of
a wing assembly in accordance with yet another embodiment of the
present invention.
[0040] FIG. 24 shows a high level diagram of an air vent assembly
including air vent flaps in accordance with an embodiment of the
present invention.
[0041] FIG. 25 shows a high level diagram of a wing assembly in
accordance with an embodiment of the present invention.
[0042] FIG. 26 shows a cross-sectional diagram of an exemplary
mounting approach for vertical thrusters in accordance with another
embodiment of the present invention.
[0043] FIG. 27 shows a high level diagram of a wing assembly in
accordance with another embodiment of the present invention.
[0044] FIG. 28 shows a high level diagram of an aircraft assembly
in accordance with an embodiment of the present invention.
[0045] FIG. 29 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0046] FIG. 30 shows a high level diagram of an aircraft assembly
in accordance with yet another embodiment of the present
invention.
[0047] FIG. 31 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0048] FIG. 32 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0049] FIG. 33 shows a three-dimensional view of an aircraft
assembly, such as the aircraft assembly of FIG. 32, in accordance
with an embodiment of the present invention.
[0050] FIG. 34 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0051] FIG. 35 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0052] FIG. 36 shows a high level diagram of the aircraft assembly
of FIG. 35 having a detached fuselage in accordance with an
embodiment of the present principles.
[0053] FIG. 37 shows a high level diagram of a cargo pod in
accordance with an embodiment of the present principles.
[0054] FIG. 38 shows schematically an example of a loading method
in accordance with another embodiment of present invention.
[0055] FIG. 39 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0056] FIG. 40 shows a high level diagram of a wing assembly in
accordance with an alternate embodiment of the present
invention.
[0057] FIG. 41 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0058] FIG. 42 shows a separated fuselage section of the aircraft
assembly of FIG. 41, otherwise known as a pod, in accordance with
an embodiment of the present invention.
[0059] FIG. 43 shows an integrated mobile pod in accordance with an
embodiment of the present invention.
[0060] FIG. 44 shows a hybrid pod in accordance with another
embodiment of the present invention.
[0061] FIG. 45 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0062] FIG. 46 shows the front (upper figure) and top (lower
figure) views of an aircraft assembly in accordance with an
embodiment of the present invention.
[0063] FIG. 47 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0064] FIG. 48 shows two front views of the aircraft assembly of
FIG. 47, in which the top figure shows the assembly with the
payload pod attached and the bottom figure shows the assembly with
the payload pod detached in accordance with an embodiment of the
present invention.
[0065] FIG. 49 shows a high level diagram of an aircraft assembly
in accordance with another embodiment of the present invention.
[0066] FIG. 50 illustrates the aircraft assembly of FIG. 49 having
the pod in a detached state in accordance with an embodiment of the
present invention.
[0067] FIG. 51 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0068] FIG. 52 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0069] FIG. 53 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0070] FIG. 54 shows the top and side views of a payload pod that
can be attached to the aircraft of FIG. 54 in accordance with an
embodiment of the present invention.
[0071] FIG. 55 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0072] FIG. 56 shows top and side views of a matching payload pod
for the aircraft of FIG. 55 in accordance with an embodiment of the
present invention.
[0073] FIG. 57 shows a high level diagram of an aircraft in
accordance with another embodiment of the present invention.
[0074] FIG. 58 shows an aircraft assembly comprised of the aircraft
of FIG. 57 and an attached payload pod in accordance with another
embodiment of the present invention.
[0075] FIG. 59 illustrates three different positions for mounting a
payload onto the aircraft assembly of FIG. 58 in accordance with an
embodiment of the present invention.
[0076] FIG. 60 shows the bottom and front views of an aircraft
assembly in accordance with another embodiment of the present
invention.
[0077] To facilitate understanding, identical reference numerals
have been used, where possible, to designate identical elements
that are common to the figures. The figures are not drawn to scale
and may be simplified for clarity. It is contemplated that elements
and features of one embodiment may be beneficially incorporated in
other embodiments without further recitation.
DETAILED DESCRIPTION
[0078] In the following detailed description, numerous specific
details are set forth in order to provide a thorough understanding
of exemplary embodiments or other examples described herein.
However, it will be understood that these embodiments and examples
may be practiced without the specific details. In other instances,
well-known methods, procedures, components, and/or circuits have
not been described in detail, so as not to obscure the following
description. Further, the embodiments disclosed are for exemplary
purposes only and other embodiments may be employed in lieu of, or
in combination with, the embodiments disclosed.
[0079] Embodiments of the present invention provide an alternative
distributed airborne transportation system, which can operate
without airports. This distributed airborne transportation system
is based on a modular distributed transport approach, which uses
relatively small-scale airborne vehicles capable of loading and
unloading passengers and cargo at the point of a service request (a
la taxi service) and of long-range travel using flight formation
and other methods. Such a distributed airborne transportation
system can offer advantages such as convenience for customers and
scalability (i.e., the ability to grow in size and capacity). At
the same time, it may be more advantageous than ground-based
distributed systems, since it does not require the creation and
maintenance of roadways on the ground. Non-limiting examples
include providing transport systems and methods based on fixed-wing
unmanned airborne vehicles with vertical take-off and landing
capabilities.
[0080] In accordance with embodiments of the present invention, an
airborne system is provided for distributed transportation of
passengers and cargo as shown in FIG. 1. In a system 100 an
airborne vehicle (vehicle 110) may be provided for a customer 120
at an arbitrary location 125. Vehicle 110 has a range of
capabilities including, but not limited to: 111--landing at a site
near customer location, 112--boarding a customer and taking off,
and 113--ascending and reaching cruising speed and altitude. At a
cruising altitude, vehicle 110 may join a fleet 130 comprised of
similar airborne vehicles to produce a flight formation. Fleet 130
may include vehicles traveling to different destinations, but along
the same route in the same general direction.
[0081] Flight formation as used herein, means an arrangement of
airborne vehicles flying in sufficiently close proximity to each
other to impact the flight characteristics of the fleet as a whole.
Fleets in flight formation may include two or more airborne
vehicles. Flight formation enables more energy efficient flight,
while giving the flexibility of entering or leaving the fleet at
any time. For example, flight in a V formation can greatly enhance
the overall aerodynamic efficiency of the fleet by reducing the
drag and thereby increasing the flight range.
[0082] Airborne vehicles that may be used in system 100 include
helicopters, fixed-wing planes, VTOL (vertical take-off and
landing) aircraft, rotorcraft, lighter-than-air airships, hybrid
aircraft and others. Some of the methods described in this
invention may also be applicable to a wider variety of aircraft
options, including regular fixed-wing airplanes. In the latter
case, however, the loading and unloading of cargo and passenger may
be restricted to special locations and take place at small airports
and airfields.
[0083] Small-scale aircraft suitable for these methods may utilize
different flight control options, such as manual piloting, remote
piloting, and automatic piloting. In the case of manual piloting,
an on-board pilot is in full control of an aircraft and its
maneuvers. In remote piloting, an aircraft is piloted by a person
that is not on board of an aircraft via a radio communication link.
In automatic piloting, an on-board computer system provides full
flight control capabilities, including flight planning, path
monitoring, maneuvering, transitioning between different aircraft
configurations and so on. Finally, in a hybrid flight control
option two or more of these options may be available, for example,
so that the same aircraft may be piloted manually, remotely, or
automatically at different times. The automatic piloting option is
particularly attractive for flight formations, where precise and
quick maneuvering is essential.
[0084] Cargo sections in these aircraft may take different forms
depending on whether passenger transport is involved. Passengers
may also be labeled as "Human Cargo" (HC) for generalization
purposes. HC transport may occur via specialized containers or HO
pods. Such pods may be loaded and unloaded onto airborne vehicles
in a similar way to regular cargo containers.
[0085] In accordance with embodiments of the present invention, one
of the preferred vehicles for this system is a fixed-wing aircraft
with vertical take-off and landing (VTOL) capabilities. It combines
the advantages of being able to take-off and land outside of
airports and fly at relatively high cruising speeds (e.g., relative
to helicopters). FIG. 2 shows, as an example of such an aircraft, a
VTOL plane 200. This plane has tailless design using a fuselage 202
with sufficient room to accommodate one or more passengers. The
wing sections, collectively 210, have built-in fans (or more
generally vertical thrusters), collectively 240, for providing a
vertical lifting force for take-off and landing. The wing section
210 may also fold its tips, collectively 220, for minimizing the
size of the landing site. After a take-off, another motor with a
propeller 250 (or more generally horizontal thrusters) may provide
propulsion to achieve sufficient speed, at which the wing has
enough lift and the fans can be turned off. At this point, the fan
openings may be shuttered 310 as shown in FIG. 3 in a VTOL vehicle
configuration 300.
[0086] Of course many other VTOL vehicles designs may be possible
within the scope of this invention. For example, FIG. 4 shows a
VTOL design 400 in which the propulsion is provided by two ducted
fans, collectively 405. In alternate embodiments of the present
invention, instead of fans, gimbaled motors with propellers can be
used for both vertical and lateral propulsion. A preferred
propulsion mechanism may include an electric motor with a
propeller. However, one may use an electrically powered plasma jet
engine as an alternative. As a result, cruising speeds, which may
be achieved either by individual vehicles or within a fleet, may
reach supersonic speeds.
[0087] Also, the wing shape may take different forms. In addition,
a VTOL design with a tail may be used as an alternative.
Folding-wing and/or folding-tail designs are particularly
attractive, because it allows VTOL vehicles to land in tighter
areas on the ground. A foldable wing is shown as an example in FIG.
2. Wings or some of their parts may be rotating to enable VTOL
capabilities, in which for example a motor attached to the wing may
be rotated by at least 90 degrees. Alternatively, other sections of
the airframe may be rotating, e.g., the fuselage or some of its
sections.
[0088] Various power systems and their combinations may be used for
powering such vehicles, including fossil fuels, electric batteries,
fuel cells, solar power, and other renewable power sources. A
particularly attractive solution for this application comprises an
electrically powered VTOL plane with additional solar photovoltaic
(PV) power system, because of its efficiency and low noise. In
addition, kinetic energy conversion systems may also be used as
alternative energy sources, particularly in emergency situations. A
preferred power system may have several redundant power sources,
such as electrical batteries, fuel cells, and solar cells.
[0089] In accordance with another embodiment of the present
invention, FIG. 5 shows an exemplary method 500 for providing
distributed airborne transportation services. The method 500
includes the following: (1) perform vertical landing, (2) pick up
passengers and/or cargo, (3) perform vertical take-off, (4)
transform to fixed-wing position, (5) increase altitude and lay out
course, (6) locate suitable fleet, (7) join a fleet in flight
formation, (8) travel to destination, (9) disengage from the fleet,
(10) descend to landing site, (11) perform vertical landing, and
(12) unload passengers or cargo. Some of these, such as (5)
increasing altitude and laying the course for the airborne vehicle,
may be optional in various embodiments. Alternatively, additional
actions may be added, such as loading and unloading of additional
passengers and/or cargo.
[0090] The above method and embodiments similar to this method, in
general, may be subdivided into three method categories: (1)
loading methods, (2) travel methods and (3) unloading methods.
Loading and unloading methods may differ depending on whether the
service is intended for passengers, cargo, or combinations thereof.
For example, additional equipment and automated loading procedures
may be implemented for loading and unloading cargo. Also, cargo may
be loaded and unloaded even without the VTOL transport vehicle
actually touching the ground, e.g., using air-to-air transfer
between airborne vehicles or via the use of cables and
parachutes.
[0091] Travel methods in particular may describe several phases of
airborne transport or more generally the flight of a VTOL aircraft.
At least two flight phases can be emphasized, including the
vertical flight phase and the horizontal flight phase. During the
vertical flight phase, the aircraft may stay airborne using
primarily its vertical propulsion system. In this phase, the lift
force is provided by the vertical thrust of the vertical propulsion
system, while the aircraft may move in an arbitrary direction
according to its flight plan, such as up, down, forward, backward,
sideways or any other direction in space. For this purpose, the
horizontal propulsion system may be used to provide not only the
forward, but also the reverse thrust for lateral movements. In
addition, the aircraft in the vertical flight phase may hover at a
constant position and altitude and may be able to change its
attitude, for example orientation in space (e.g., yaw, roll and
pitch angles). This flight phase may implemented for example
immediately after a take-off or before a landing. During the
horizontal flight phase, the aircraft may stay airborne using
primarily its horizontal propulsion system. In this flight phase,
the lift force is provided by the aerodynamic lift of the aircraft
wing, which arises from the forward motion of the aircraft
activated by the horizontal propulsion system. The aircraft motion
in the horizontal flight phase is somewhat limited in comparison to
the vertical flight phase, so that the aircraft may move
substantially in the horizontal plane, i.e. it may have to maintain
a substantial horizontal component of its velocity vector in order
to stay airborne. In addition, the aircraft in the horizontal
flight phase may be able to perform typical fixed-wing aircraft
flight maneuverers, such as ascent, descent, turns and others. In
addition to these two main flight modes, other flight modes may
exist, including transitional and hybrid modes, in which both
vertical and horizontal propulsion systems may be engaged at the
same time providing lift and maneuvering capabilities.
[0092] In accordance with some aspects of the present invention,
FIG. 6 shows schematically an example of a loading method 600,
which may be used, for example, in combination with the method 500
disclosed above. In some embodiments, the method 600 includes:
performing a vertical landing of a vehicle 615 (shown by 610),
loading a passenger 616 (shown by 620), and performing a vertical
take-off by vehicle 615 with passenger 616 on board (shown by 630).
Furthermore, the method 600 may further include a vertical ascent,
in which the speed of the vehicle is substantially vertical and the
lateral (horizontal) speed component may be smaller than the
vertical speed component. Of course, the same method may be applied
to loading of multiple passengers at the same location and/or
loading of cargo. Alternatively, the process described by method
600 may be repeated at different sites and locations, so that
different passengers and cargo or types of cargo may be loaded onto
the same vehicle 615 (with or without complete or partial unloading
of any existing passengers or cargo).
[0093] In accordance with another aspect of the present invention,
FIG. 7 shows schematically an example of a travel method 700, which
may be used, for example, in combination with the method 500
disclosed above. In some embodiments, the method 700 includes:
increasing altitude of vehicle 715 using its VTOL capabilities
(shown by 710), transforming vehicle 715 to a fixed-wing position
and increasing its lateral (horizontal) velocity (shown by 720),
locating a suitable fleet of airborne vehicles (fleet 735) and
joining fleet 735 in flight formation (shown by 730), travelling
towards a destination with fleet 735 (shown by 740), disengaging
from fleet 735 (shown by 750), descending towards a landing site
and transitioning to a vertical landing position (shown by 760),
and reducing the altitude of vehicle 715 using its VTOL
capabilities (shown by 770). Instead of joining an existing fleet,
vehicle 715 may also join another airborne vehicle (similar or
dissimilar) and thereby forming a two-vehicle fleet.
[0094] Of course, some of the above may be optional and omitted, or
alternatively additional actions may be introduced. For example,
vehicle 715 may communicate with fleet 735 before and/or after
joining the fleet. Also, the vehicle 715 may travel for substantial
distances without an accompanying fleet. Furthermore, some actions
may be repeated. For example, vehicle 1010 may switch between
different fleets 1020 and 1030, as shown by 1000 in FIG. 10, in
which a part of its course may be travelled with one suitable fleet
(e.g., 1020) and another part of the course may travelled with a
different, preferably more suitable, fleet (e.g., 1030). The
different fleet may be more suitable by providing one or more of a
different flight path, a different destination, a more efficient
flight formation, or the like. Alternatively or in combination, the
method 700 may include changing the position of vehicle 715 within
fleet 735. In some embodiments, the method 700 may include
refueling and recharging of an airborne vehicle by another airborne
vehicle (optionally within the same fleet), in which fuel and/or
electrical energy respectively are exchanged between the two
vehicles with assistance of a transfer line or a cable. Any travel
method may also include optional actions related to emergency
situations, in which a vehicle performs one or more actions
necessary for communicating with a fleet and/or flight control
authorities, quick disengagement from a fleet, rapid decent, or the
like.
[0095] In accordance with yet another aspect of the present
invention, FIG. 8 shows schematically an example of an unloading
method 800, which may be used, for example, in combination with the
method 500 disclosed above. In some embodiments, the method 800
includes: performing a vertical landing of a vehicle 815 (as shown
by 810), unloading a passenger 816 (as shown by 820), and
performing a vertical take-off by vehicle 815 (as shown by 830).
Furthermore, the method 800 may include a vertical descent before
landing, in which the speed of the vehicle is substantially
vertical. Of course, the same method may be applied to unloading of
multiple passengers at the same location and/or unloading of cargo.
Alternatively, the process described by method 800 may be repeated
at different sites and locations, so that different passengers and
cargo or types of cargo may be unloaded onto the same vehicle 815.
Furthermore, both loading and unloading methods include landing on
suitable surfaces such as ground surfaces, roof surfaces
(especially flat roofs), flight decks of large building and
vehicles, floating decks on water surfaces, water surfaces (with
appropriate landing gear), road surfaces, off-road surfaces, and so
on.
[0096] In accordance with embodiments of this invention, loading,
unloading, and travel methods described above may be modified,
shortened, expanded, and combined with each other to produce
different sequences of procedures for airborne transportation
services. For example, loading methods may be combined with
unloading methods, so that the same airborne vehicle may be used
for loading and unloading passengers/cargo at the same location at
the same time. In another example, the same airborne vehicle may be
used for loading and/or unloading passengers/cargo at the same
location at the same time while one or more passengers and/or cargo
remains on the plane to continue to a subsequent destination.
[0097] In accordance with another embodiment of this invention,
different fleet configurations may be used in the travel methods
described above. FIG. 9 shows examples of several fleet
configurations 910-950, which differ from each other in size,
shape, and number of members. At least one of the driving factors
for a fleet formation is the optimization of energy consumption by
each vehicle within the fleet. By flying next to each other,
vehicles in a fleet as a whole reduce the power necessary for their
propulsion in a level flight. Generally, the power reduction is
larger in a larger fleet. Thus, the fleet is able to perform level
flight on net propulsion power that is less than sum of propulsion
powers of all its airborne vehicles flown separately. The
inter-vehicle separation within the fleet should be less than 100
wing spans of typical member vehicle and generally may vary from
tens to a fraction of the characteristic wing-span of its members.
In order to minimize the size of the fleet and maximize its
efficiency, the separation between neighboring airborne vehicles
may be preferable to be less than 10 wing spans. It is also
preferable that lateral separation (along the wing span) between
airborne vehicles is substantially smaller than the longitudinal
separation (along the flight path). The altitude of the airborne
vehicles in flight formation may be substantially the same. The
difference in altitude may be governed by the requirement to retain
the aerodynamic drag reduction in flight formation and typically is
a fraction of the wing span of the airborne vehicle.
[0098] As a result, fleets may form complex two-dimensional and
three-dimensional patterns. Aircraft within a single fleet may
change their positions with respect to each other, in order to
optimize their power consumption, change fleet configuration and
respond to environmental changes. Due to this complexity,
autonomously piloted vehicles (APV) may be better at formation
flying in comparison to manually piloted aircraft. Auto-piloting
software on board of APVs may be further specialized for formation
flying. Additional APV capabilities that simplify formation flying
may include direct communication channels between different APVs
within a fleet, local area networking capabilities for data
exchange within a fleet (e.g. ad hoc networking), sensors and
beacons for automatic collision avoidance, etc.
[0099] The fleets described above may have at least two ways to
organize themselves into a stable formation. One way is via a
centralized control from a single command source following
procedures and patterns formulated in advance. The other way is via
a distributed (ad hoc) control mechanism, in which each airborne
vehicle determines its position within its fleet autonomously, and
with the assistance from other vehicles from the same fleet only if
necessary. The latter approach of a self-organizing airborne fleet
is particularly attractive and should be a preferred way, since it
is faster, safer, more economical, responsive, adaptive, and
scalable.
[0100] In accordance with another embodiment of the present
invention, FIG. 11 shows a distributed transportation system 1100,
which includes a control center 1110, individual airborne vehicles
1120, and fleet of airborne vehicles 1130. The control center and
each vehicle are equipped with means for wireless communications
(e.g., 1111 in FIG. 11), such as RF antennas, transmitters, and
receivers. Alternatively, this means may include free space optical
communications equipment. As a result, the system 1100 is
configured to have bi-directional wireless links between its
components (i.e., ground based stations and airborne assets) for
exchange of flight control signals, telemetry data, navigational
signaling, and so on. For example, FIG. 11 shows wireless links
1125 between the control center 1110 and the individual airborne
vehicles 1120 and wireless links 1135 between the control center
1110 and the fleet of airborne vehicles 1130, as well as direct
wireless links 1126 between individual airborne vehicles 1120. In
addition, system 1100 is provided with communication links to
customers and/or their premises 1140, including wireless links 1145
and wired links 1146, for the purposes of receiving customer
orders, tracking their location, updating their status, exchanging
relevant information and so on. Furthermore, a direct communication
link 1155 between an airborne vehicle 1120 and customers/premises
can be established for faster and more accurate exchange of
information. Thus, as shown in FIG. 11, one or more communication
links can be established with an airborne vehicle to provide one or
more of customer information, navigational data, or flight data
from other airborne vehicles to the airborne vehicle.
[0101] Furthermore, the system 1100 may be expanded to include
other elements. For example, it may comprise multiple fleets of
various sizes that are able to dynamically vary in size and
complexity. It may include additional ground-based facilities, such
as additional control centers, maintenance centers, heliports,
communication towers and so on. It may include parking areas for
vehicles on stand-by, waiting for passengers. It may also include
sea-based facilities, such as aircraft carriers, sea-based control
centers (for example, located on boats and sea vessels), and
aircraft suitable for landing on water. Furthermore, it may include
space-based facilities, such as satellites for establishing
additional communication links between control centers, airborne
vehicles and customers.
[0102] In accordance with another embodiment of this invention,
FIG. 12 shows a distributed transportation system 1200, in which
flight formation is used for organizing airborne transportation in
the urban area. In this case an area on the ground may be densely
populated with people and buildings 1210. Such an area may be
heavily trafficked both on the ground and in the air. Formation
flying may be a useful tool under such conditions for organizing
flight patterns of and ensuring safety of multiple small-scale
aircraft of the type described in the above, even for short range
travels within the same metropolitan area. In this case, minimizing
fleet power consumption is unimportant or less important, and
different flight formations are therefore possible. For example,
FIG. 12 shows two fleets 1220 and 1230, each comprised of multiple
airborne vehicle 1225 and 1235 in a straight line. These fleets are
able to fly in formation in different directions without collision
and interference from each other by having different altitudes
and/or different lateral positions.
[0103] Similarly, FIG. 13 shows a top view of a distributed
transportation system 1300 in an urban area populated with
buildings 1310. The system 1300 includes two fleets 1320 and 1330,
each comprised of multiple aircraft 1325 and 1335 in flight
formation. The aircraft in the same formation maintain the same
speed, heading, altitude and separation between neighboring
aircraft. Flight routes for such fleets may be predefined in
advance and programmed in with GPS (Global Positioning System)
markers in the flight control software. Therefore, the two fleets
at different altitudes may cross each other paths without
interference as illustrated in FIG. 13. Typical separation between
different aircraft in urban flight formation may range from 1 to 10
wing spans of a single airborne vehicle, but in general cases may
exceed this range. Urban areas also provide additional options for
take-off and landing, such as roofs of the buildings. VTOL vehicles
may use flat roofs as convenient and safer alternative for loading
and unloading of passengers and cargo. In this case, the roof may
be appropriately modified to fit the requirements of such VTOL
vehicles, for example, by providing launching/landing pad markings,
roof reinforcements to support the weight of aircraft, clearance
for landing and take-off above a launching/landing pad, support
facilities to accommodate cargo, passengers and aircraft for
maintenance and so on.
[0104] Although various methods and apparatus are described above
in particular exemplary embodiments, variations and combinations of
the methods and apparatus are contemplated. For example the
disclosed methods may be performed in connection with any of the
disclosed systems and airborne vehicles, as well as with other
alternative systems and vehicles. In addition, various
modifications of the methods, such as omitting optional processes
or adding additional processes may be performed.
[0105] For example, in some embodiments, a method for distributed
airborne transportation may include providing an airborne vehicle
with a wing and a wing span, having capacity to carry one or more
of passengers or cargo (e.g., any of the airborne vehicles
disclosed above). The airborne vehicle may be landed near one or
more of passengers or cargo and the at least one of passengers or
cargo loaded into the airborne vehicle. Next, the airborne vehicle
takes-off and a flight direction for the airborne vehicle is
determined. At least one other airborne vehicle having
substantially the same flight direction is located. The airborne
vehicle then joins at least one other airborne vehicle in flight
formation to form a fleet, in which airborne vehicles fly with the
same speed and direction and in which adjacent airborne vehicles
are separated by distance of less than 100 wing spans.
[0106] In another example, a method for distributed airborne
transportation within an area on the ground may be provided by
providing an airborne vehicle with a wing and a wing span, having
capacity to carry at least one of passengers or cargo (e.g., any of
the airborne vehicles disclosed above). Non-intersecting flight
routes in the area are determined and defined. The airborne vehicle
is landed and at least one of passengers or cargo is loaded into
the airborne vehicle. The airborne vehicle then takes-off and an
appropriate flight route for the airborne vehicle is selected. The
airborne vehicle then merges into the flight route.
[0107] In another example, a distributed airborne transportation
system includes a plurality of airborne vehicles, each having a
wing and vertical take-off and landing capabilities (e.g., any of
the airborne vehicles disclosed above). An airborne fleet is
defined comprising at least two of the plurality of airborne
vehicles flown in flight formation (e.g., as described in any of
the embodiments disclosed herein). The lateral and vertical
separation between the airborne vehicles within the fleet is less
than the average wingspan of the plurality of airborne vehicles in
the airborne fleet. A flight control center (e.g., 1110) is
provided with established wireless communication links between the
flight control center and the plurality of airborne vehicles.
[0108] In accordance with various embodiments of the present
invention, one of the preferred vehicles for the above described
methods and system is a fixed-wing aircraft with vertical take-off
and landing (VTOL) capabilities. Such an aircraft of the present
invention combines the advantages of being able to take-off and
land outside of airports and fly at relatively high cruising speeds
(e.g., relative to helicopters). FIG. 14 shows a functional block
diagram of an aircraft, illustratively a VTOL plane 1400, in
accordance with an embodiment of the present invention. The
functional block diagram of the VTOL plane 1400 of FIG. 4
illustratively includes an airframe 1405 and systems for power
(power system 1410), flight control 1415, horizontal 1420 and
vertical propulsion 1425. As will be depicted and described with
reference to figures described below, the airframe 1405 may include
one or more wing portions, a fuselage, and an empennage (a tail
section). In accordance with various embodiments of the present
invention, parts of the airframe 1405 may be modular and/or may be
able to change its form (e.g. a modular fuselage that can be
separated into multiple sections, a foldable wing that can change
its shape in flight, etc.). In various embodiments of the present
invention, the power system 1410 may include fuel storage and fuel
distribution subsystems, electrical storage (e.g. batteries), power
generation units (e.g. solar photovoltaic power systems, fuel cells
and electrical generators), electrical power distribution circuits
and power electronics (not shown). The horizontal and vertical
propulsion systems may include propulsion means, such as
propellers, turbines and jets, powered by engines and/or electrical
motors. The horizontal and vertical propulsion systems may be
separate from each other, so that they can be designed and operated
independently.
[0109] VTOL aircraft in accordance with various embodiments of the
present invention, unlike more conventional VTOL aircraft, can have
several distinguishing features. In one embodiment in accordance
with the present invention, a VTOL aircraft has separate propulsion
systems for vertical and horizontal transport, so that the vertical
propulsion system serves primarily the purpose of providing the
vertical (upward) thrust and the horizontal propulsion system
serves primarily the purpose of providing the forward thrust. Such
embodiments enable a more efficient design, the ability of separate
optimization and better performance of each propulsion system. Such
embodiments also enable integration of very different propulsion
mechanisms, for example jet propulsion and propeller-driven
propulsion for the horizontal and vertical propulsion systems,
respectively, or vice versa.
[0110] In alternate embodiments, the vertical propulsion system may
be housed in the main wing of a VTOL aircraft, rather than a
separate part of the airframe. In such embodiments, the housing for
vertical thrusters may be integrated into the wing structure. To
achieve this, the wing of a VTOL aircraft may include openings for
vertical thrusters. As a result, the wing may serve a dual purpose
of housing the vertical propulsion system and providing the lift
force during the horizontal flight phase. The lift force may be
provided by the entire surface of the wing including the wing
portion with the openings and housing for the vertical thrusters.
The extension of the lifting surface to the area around the wing
openings may be accomplished by providing a continuous airfoil
shape throughout the wing, including the openings.
[0111] In order to further illustrate this point, FIG. 40 shows a
wing assembly 4000, comprising a wing surface 4010 and at least one
wing opening 4020 for housing a vertical thruster (not shown). Also
a section of the wing 4030 around the wing opening 4020 is
highlighted. The section 4030 may in turn comprise at least the bow
section 4031 and the aft section 4032, which are the areas of the
wing immediately before and after the wing opening 4020,
respectively, along the flight direction of the wing. The whole
section 4030 and the sections 4031 and 4032, in particular, may be
shaped to have airfoil profiles to minimize the drag and provide
the aerodynamic lift force.
[0112] In alternate embodiments, the wing openings for vertical
propulsion system may include air vents, which may be closed to
cover vertical thrusters and create a continuous wing surface on
both sides of the wing in the horizontal flight phase. This may
further increase the lift force of the wing in the horizontal
flight phase by increasing the area of the wing lifting surface.
The air vents may include flaps that allow the wing to form a
continuous airfoil surface on both sides of the wing in the wing
opening area. Such an embodiment enables integration of much larger
vertical thrusters and/or larger number of vertical thrusters than
would be possible without the air vents.
[0113] In various embodiments of the present invention, vertical
thrusters may have slim profiles to fit inside the wing openings.
The wing thickness in the area of the wing opening should be
sufficiently large to encompass the entire vertical thruster
assembly and enable any existing air vent to close. Various
embodiments enabling the slim design are depicted and described
with reference to the following Figures, including, in particular,
shaft-less vertical thrusters described below.
[0114] In various embodiments of the present invention, the
vertical and horizontal propulsion systems may function
independently from each other and their operation may be enabled by
either a single flight control system or a dual flight control
system; the latter comprising two flight control subsystems, which
control the vertical and horizontal propulsion systems,
respectively. In such embodiments, the two propulsion systems may
also operate concurrently, simultaneously providing the vertical
and horizontal thrusts, for example during a transition period
between the vertical flight and horizontal flight phases. In such
embodiments, a hybrid flight control mode may be executed by the
flight control system that enables and synchronizes the
simultaneous operation of the vertical and horizontal propulsion
systems. Due to the complexity of such an operation, in such
embodiments, flight control modes may be at least in part
automated.
[0115] In accordance with various embodiments, a VTOL aircraft of
the present invention may enable hybrid flight modes unavailable in
a conventional aircraft, in which the vertical and horizontal
propulsion systems are operated simultaneously. For example, in one
embodiment the propeller-based vertical thrusters may provide lift
in the horizontal flight phase using auto-gyro effect, as described
in more detail below. In alternate embodiments, the vertical
thrusters may be used in the horizontal flight phase for attitude
changes of an aircraft in place of conventional flight control
surfaces, such as ailerons, elevators and rudders, which is
described in further detail below.
[0116] FIG. 15 shows a high level diagram of a wing assembly 1500
in accordance with an embodiment of the present invention. The wing
assembly 1500 of FIG. 15 illustratively includes a wing body 1510,
and wing openings 1520, 1530 that are used for housing vertical
propulsion fans or thrusters consisting of mounting frames 1522 and
1532, motor shafts 1524 and 1534, and propellers 1526 and 1536. In
accordance with various embodiments of the present invention, a
wing assembly may include one or more opening for mounting a
vertical propulsion assembly. The wing openings provide an airflow
passage through a wing, which is necessary for achieving a vertical
thrust for either take-off or landing. In accordance with various
embodiments, the propellers 1526 and 1536 may have either fixed or
variable pitch, allowing for a greater flexibility in the design
and operational capabilities of an aircraft, such as a VTOL
aircraft of the present invention. In various alternate embodiments
of the present principles, engines and other torque-producing
machines may be used in place of motors used to drive the
propellers. Also, in alternate embodiments of the present
invention, direct thrust-producing machines, like jet engines, may
be used in place of propeller-based propulsion.
[0117] FIG. 16 shows a high level diagram of a wing assembly 1600
in accordance with an alternate embodiment of the present
invention. The wing assembly 1600 of FIG. 16 illustratively
includes a wing body 1610, and wing openings 1620 and 1630 that are
used for housing vertical thrusters consisting of shaftless
propellers 1622 and 1632, and rims 1624 and 1634. In the embodiment
of FIG. 16, the propellers 1622 and 1632 are attached to the
respective rims, which are in turn connected to the frames of the
wing openings 1620 and 1630 in such a way as to allow the rims to
rotate freely around their respective axes. In one embodiment of
the present invention, this is achieved by using either contact
suspension, e.g. with ball bearings, or contactless suspension,
discussed in more detail below. In alternate embodiments of the
present invention, the rims may also contain ring motors or parts
of ring motors that provide the torque required for their
rotation.
[0118] For purposes of clarification, FIG. 17 shows a blown-up view
of a free-standing, shaft-less propeller assembly 1700 in
accordance with an embodiment of the present invention. The
propeller assembly 1700 of FIG. 17 illustratively includes a rim
1710 and four propeller blades 1720. It should be noted that, in
accordance with the present principles, the number of propellers
may vary, however, it may be preferred to have at least two blades
for a balanced rotation. The propeller blades may have either fixed
or variable pitch. In various embodiments of the present
principles, the whole or a part of the assembly 1700 may be
constructed from lightweight composite materials, either as a
single piece or from multiple pieces. The advantages of such a
shaft-less, rim-driven propeller in comparison to a typical
shaft-driven propeller include at least greater propeller
efficiency, more compact design, lower profile, lower weight due to
lack of a shaft and its mounting frame.
[0119] FIG. 18 shows an exemplary mounting approach 1800 for
shaft-driven propellers, such as the propellers 1526, 1536 of FIG.
15 in accordance with an embodiment of the present invention. In
the embodiment of FIG. 18, the wing body 1810 includes an opening
1820 for housing a mounting frame 1830. The opening 1820 may be
used for attaching a shaft 1840 with mounted propeller 1850. The
shaft 1840 may comprise an electric motor (not shown) or other
engine (not shown) for rotating the propellers with respect to the
frame 1830. As depicted in the illustrative embodiment of FIG. 18,
the opening 1820 may have an additional clearance for the blades of
the mounted propeller 1850.
[0120] FIG. 19 shows an exemplary mounting approach 1900 for
rim-driven propellers, such as for example the propellers 1622 and
1632 of FIG. 16 in accordance with an embodiment of the present
invention. In the embodiment of FIG. 19, the wing body 1910
includes an opening 1920 and a suspension mechanism 1930. The
suspension mechanism 1930 may be used for holding a rim 1950 with
rim-mounted propeller blades (not shown). The suspension mechanism
may be in mechanical contact with the rim 1950 using a ball bearing
assembly 1940 or other friction-reducing apparatus. Alternatively,
a contactless suspension may be used, for example such as magnetic
suspension systems or a suspension system based on pressurized air
streams. In an embodiment including magnetic suspension,
electrically activated and permanent magnets may be used to
levitate the rim 1950 between the edges of the suspension mechanism
1930. In an embodiment including air stream suspension, high
pressure air streams can be blown into the gap between the rim 1950
and the suspension mechanism 1930, allowing the rim 1950 to hover
and maintain separation with the suspension mechanism 1930. In
various embodiments, the rim 1950 and suspension mechanism 1930 may
be integrated together with an electric motor (not shown) for
rotating the rim 1950 with respect to the frame wing body 1910. For
example, in such an embodiment, the rim 1950 may contain the rotor
of a ring motor, while the suspension mechanism 1930 may contain
the stator of the ring motor.
[0121] FIG. 20 shows a high level cross-sectional diagram of a
portion of a wing assembly in accordance with an alternate
embodiment of the present invention. Illustratively, in the
embodiment of FIG. 20, air vents 2030 are included to provide, for
example, vertical thrust generation. That is, the wing assembly
2000 shown in FIG. 20 may include a wing body 2010, a wing opening
2020, and air vents 2030. The air vents 2030 may be opened and
closed using louvres or flaps 2040. The wing opening 2020 may be
used to house a thruster, which is not shown in FIG. 20. The air
vents 2030 in the open position allow the air flow to pass from the
top to the bottom of the wing through the wing opening, and in the
closed position extend the closed area of the wing and increase the
lift force and cover and protect the vertical thruster housed
inside the wing opening.
[0122] FIG. 21 shows a high level, top view diagram of a portion of
a wing assembly 2100, such as the wing assembly of FIG. 20, in
accordance with an embodiment of the present invention. The wing
assembly 2100 of FIG. 21, illustratively includes a wing body 2110,
an opening 2120 and air vent flaps 2130. The air vent flaps 2130
may be aligned along the direction of flight 2140.
[0123] FIG. 22 shows a high level, top view diagram of a portion of
a wing assembly 2200 in accordance with an alternate embodiment of
the present invention. The wing assembly 2200 of FIG. 22
illustratively includes a wing body 2210 with an opening 2220 and
air vent flaps 2230 perpendicular to the flight direction 2240. In
some applications, the wing assembly 2200 of FIG. 22 may be more
beneficial than the wing assembly 2100 of FIG. 21, because it
allows the flap surfaces in their closed position to better follow
the airfoil contour of the wing assembly 2200.
[0124] FIG. 23 shows a high level, top view diagram of a portion of
a wing assembly 2300 in accordance with yet another alternate
embodiment of the present invention. The wing assembly 2300 of FIG.
23 illustratively includes a wing body 2310, a wing opening 2320
and air vent flaps 2330, illustratively arranged in a rectangular
grid pattern. The air vent flaps 2330 of FIG. 23 provide more
flexibility in the aircraft design and operation and improves its
performance by providing higher lift in forward flight.
[0125] FIG. 24 shows a high level diagram of an air vent assembly
including air vent flaps in accordance with an embodiment of the
present invention. The air vent flaps of the present invention may
be opened and closed either individually or together. The air vent
2400 of FIG. 24 illustratively includes a vent grid 2410 and vent
flaps 2420. In the air vent assembly 2400 of FIG. 24, three
different vent configurations 2401, 2402, and 2403 are shown
corresponding to open, partially open and closed vent positions,
respectively. In the embodiment of FIG. 24, a rectangular vent grid
2410 is chosen, however, many other shapes, forms and sizes are
possible within the scope of this invention (e.g. square, round,
oval, polygonal etc.). The vent flaps 2420 may also include hinges
(not shown) and actuators (not shown) that enable the opening and
closing of the flaps. In various embodiments, the actuators may be
powered mechanically, electrically or pneumatically to provide an
active force for the actuation. Alternatively, the actuators may be
passive, for example the flaps may be spring-loaded, so that under
normal conditions when the vertical thrusters are not activated,
they are in a closed position, but they may open under the
influence of the vertical airflow when the thrusters are producing
vertical thrust. In addition to flaps, other air vent shuttering
mechanisms may be used, including sliding screens, diaphragm
shutters, folding doors, rolling shutters and so on in accordance
with various embodiments of the present invention.
[0126] FIG. 25 shows a high level diagram of a wing assembly 2500
in accordance with an embodiment of the present invention. The wing
assembly 2500 of FIG. 25 illustratively includes a wing body 2510
and wing openings 2520. The wing openings 2520 may be used to
contain thrusters used for vertical propulsion comprising a frame
2522, a shaft 2524 and propeller blades 2526. Alternatively and as
described above, a shaft-less vertical propulsion system may be
used. As depicted in the wing assembly 2500 of FIG. 25, in various
embodiments of the present invention, at least one of the wing
openings 2520 may include air vents 2540. The air vents 2540 may be
opened to provide vertical airflow between the top and bottom of
the wing assembly 2500, when the thruster is turned on to produce
vertical thrust. The air vents 2540 may be closed when the aircraft
is in a horizontal flight phase, when the horizontal thruster is
engaged and the lift is generated primarily by the wing, rather
than the vertical propulsion system. The closed air vents 2540 may
closely reproduce the shape of the wing airfoil, so that the wing
section with the openings may be able to generate substantially the
same lift as the whole wing sections and the overall aerodynamic
lift is maximized and the total drag is minimized.
[0127] Alternatively, the thrusters used for vertical propulsion
during vertical ascent or descent may be used to produce lift
during forward flight as well. Instead of using air vents to
improve the wing aerodynamics, the lift may be produced by either
powered or unpowered rotating propellers during forward flight via
an autogyro lift effect, in which the vertical thruster propellers
may auto-rotate under the influence of incoming air flow and
generate vertical lift in a similar way to that of a fixed
wing.
[0128] In accordance with alternate embodiments of the present
invention, a method for transitioning from vertical to horizontal
flight of a VTOL aircraft is provided, in which the horizontal
propulsion system provides forward thrust and the vertical
propulsion propellers are enabled to auto-rotate and provide at
least a portion of the lift necessary to maintain a level flight.
The auto-rotation may occur when the propellers are allowed to spin
freely. At least for this purpose the vertical propulsion system
may include a gearbox, which may enable for the vertical thruster
propellers to disengage from the motor (or other torque-producing
machine), switch to a neutral gear and enable free rotation of the
vertical thruster propellers. In addition, the gearbox may be used
to change the gear ratio between the motor and the propellers
allowing them to rotate at different rates, so that the vertical
propulsion system may be used in different flight modes and
different flight mission requiring different thrust capabilities.
For example, an empty aircraft and fully loaded aircraft may have
different weights and thus require different vertical thrusts,
which can be changed and optimized by varying the gear ratio.
[0129] FIG. 26 shows a cross-sectional diagram of an exemplary
mounting approach 2600 for vertical thrusters in accordance with an
alternate embodiment of the present invention. That is, FIG. 26
shows a mounting approach 2600 for vertical thrusters with
additional mechanical capabilities in accordance with an embodiment
of the present invention. In the embodiment of FIG. 26, the wing
body 2610 may have an opening 2620 for housing a mounting frame
2630. The mounting frame 2630 may be used for attaching a gimbal
mount 2660, which in turn may hold a motor shaft 2640 with
shaft-mounted propellers 2650. The gimbal mount may have one or two
axes of rotation and may be used to tilt the vertical thruster
assembly with respect to the mounting frame 2630 and the rest of
the airframe, which may be useful under different flight
conditions. More specifically, during the vertical flight phase,
when the lift is produced primarily by the vertical propulsion
system, the tilting gimbal mount 2660 may be used to stabilize an
aircraft and provide a horizontal thrust component in the direction
determined by the tilt direction. During the horizontal flight
phase, when the lift is produced primarily by the wings, the
tilting gimbal mount 2660 may be used to control the autogyro lift
produced by the auto-rotating propellers. This enables the
independent control of the angles between the wing and the vertical
thruster propellers. Alternatively, in alternate embodiments of the
present invention, instead of shaft-mounted propellers, rim-mounted
propellers (e.g. FIG. 19), may be used to achieve a similar
functionality. In such an embodiment, the rim assembly may be
rotated as a whole around one or two axes to tilt vertical thrust
in one or more directions.
[0130] In accordance with the present invention, the vertical
propulsion system may comprise one or multiple thrusters, where
each vertical thruster may be housed in a separate opening of an
aircraft wing. The number of thrusters may be selected depending on
characteristics of the aircraft and the thrusters. Also, different
thrusters (e.g. having different sizes or thrust capabilities) may
be used in the same vertical propulsion system. For example, a
delta-wing aircraft having a wing with a triangular shape, may have
a vertical propulsion system with three thrusters. If similar
propeller-based thrusters are used in this case, then each thruster
may comprise two coaxial propellers that are counter-rotating with
respect to each other to improve stability of the aircraft. The
coaxial counter-rotating propellers may be also used in other
configurations with different number of thrusters, in order to
increase the total thrust while minimizing the footprint of the
resulting vertical propulsion system. A system with a small number
of thrusters may require relatively large and powerful thrusters,
while a system with a larger number of thrusters may be able to
function with much smaller, but more efficient thrusters as
illustrated below.
[0131] FIG. 27 shows a high level diagram of a wing assembly 2700
in accordance with an alternate embodiment of the present
invention. The wing assembly 2700 of FIG. 27 illustratively
includes a wing body 2710, multiple wing openings 2720 and optional
air vents 2730. In the wing assembly 2700 of FIG. 27, the wing
openings 2720 may be used to house vertical thrusters. The air
vents 2730 may be opened and closed independently from each other
as shown in FIG. 27. That is, wing assembly 2701 depicts wing air
vents which are all fully closed, wing assembly 2702 depicts some
wing air vents which are open and some wing air vents which are
closed and wing assembly 2703 depicts wing air vents which are all
fully open. Such a configuration in accordance with embodiments of
the present invention, enables the gradual adjustment of the
vertical thrust produced by the thrusters and improves the
transition between the vertical and the horizontal flight phases
described above. In addition, in various embodiments of the present
invention, vertical propellers may be allowed to auto-rotate in the
horizontal flight phase and produce lift in the vent open
positions.
[0132] FIG. 28 shows a high level diagram of an aircraft assembly
2800 in accordance with an embodiment of the present invention. In
the embodiment of FIG. 28, the aircraft assembly 2800 comprises a
VTOL aircraft having a wing shape and as such, in various
embodiments of the present invention, such as the embodiment of
FIG. 28, the entire aircraft assembly 2800 can be considered a wing
or wing portion.
[0133] The inventors determined that a small aspect ratio wing,
where the ratio of a wing span to the average chord is less than
10, may allow better placement of vertical propulsion fans on a
wing. At the same time, close formation flight may counteract some
of the inefficiencies due to the small aspect ratio of a wing. The
aircraft assembly 2800 of FIG. 28 comprises a tailless aircraft
including a wing portion 2810, wing openings, collectively 2820,
and vertical thrusters, illustratively propellers 2831, 2832, 2833
and 2834. The aircraft assembly 2800 of FIG. 28 may further include
a horizontal propulsion system (not shown). FIG. 28 shows four wing
openings, but similar results may be achieved with any number of
wing openings greater or equal than 3.
[0134] In accordance with the present invention, the aircraft
assembly 2800 may be able to use the vertical thrusters for
controlling its roll, yaw and pitch, which thus would enable not
only the vertical take-off and landing, but also the maneuvering
capabilities in the horizontal flight phase, such as turning,
rolling, ascending and descending. For example, a positive vertical
thrust provided by either of the propellers 2832 or 2834 may roll
the aircraft assembly 2800 left or right, respectively and a
vertical thrust provided by either the propellers 2831 or 2833 may
pitch the aircraft assembly 2800 up or down, respectively.
Maintaining the same thrust level by both thrusters in each pair of
thrusters (2831 and 2833, or 2832 and 2834), so that they rotate in
the same direction, may yaw the aircraft assembly 2800 to the left
or to the right, thus turning the aircraft in a new direction. To
compensate for unwanted roll, pitch and yaw all four thrusters may
be turned on in order to provide a necessary maneuver. In various
embodiments of the present principles, the aircraft assembly 2800
may include an automatic flight controller (an auto-pilot), which
coordinates the torques and thrusts of all vertical thrusters in
order to produce a desired maneuver involving changes in pitch,
roll and yaw angles. The thrust produced by each thruster in this
case may be substantially smaller than the thrust achieved during
the vertical flight phase. In various embodiments of the present
invention, the thrusters of the present invention can be controlled
individually to provide flight control for the aircraft assembly of
the present invention. That is, in accordance with various
embodiments of the present invention, the thrusters can be
individually turned on and off and the thrust of each thruster can
also be controlled individually.
[0135] FIG. 29 shows a high level diagram of an aircraft assembly
2900 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 2900 of FIG. 29 comprises a
tailless aircraft including a wing portion 2910, wing openings,
collectively 2920, vertical thrusters, collectively 2930, and
ailerons, collectively 2940. The aircraft assembly 2900 of FIG. 29
may further include a horizontal propulsion system (not shown). A
difference between the aircraft assemblies 2800 and 2900 is that
the latter has additional flight control surfaces that enable
aircraft maneuvering in the horizontal flight phase. Unlike a
regular plane, the aircraft assembly 2900 of the present invention
has an option to use the vertical thrusters for horizontal
maneuvering as described above with respect to the aircraft
assembly 2800, which also increases its flight control redundancy
and maneuvering capabilities in accordance with the present
invention.
[0136] FIG. 30 shows a high level diagram of an aircraft assembly
3000 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3000 of FIG. 30 includes a wing
portion 3010, wing openings, collectively 3020, vertical thrusters,
collectively 3030, a vertical propulsion frame 3040, wing spars
3050 and a horizontal propulsion system with a motor 3060 and a
propeller 3065. In various embodiments of the present invention,
the vertical propulsion frame 3040 and wing spars 3050 may be
imbedded in the aircraft assembly 3000 and hidden from view. The
vertical propulsion frame 3040 and wing spars 3050 are shown in
FIG. 30 for clarity.
[0137] In the embodiment of FIG. 30, the vertical propulsion frame
3040 is used to hold together the vertical thrusters 3030 and to
transfer the vertical thrust produced by the vertical thrusters
3030 to the airframe of the aircraft assembly 3000. The rest of the
airframe is mechanically supported by the wing spars 3050. In one
embodiment of the present invention, the vertical propulsion frame
3040 is attached directly to the wing spars 3050. The horizontal
propulsion system may be used to provide horizontal thrust to the
airframe. In alternate embodiments of the present invention, other
airframe components may be included in the VTOL aircraft assembly
3000, such as a payload bay (not shown), a fuselage (not shown), a
tail (not shown), flight control surfaces (not shown), landing
gears (not shown), additional motors and propellers (not shown),
air vents (not shown), flight control systems (not shown), payloads
(not shown) and others.
[0138] FIG. 31 shows a high level diagram of an aircraft assembly
3100 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3100 of FIG. 31 includes wing
portions, collectively 3110, a wing spar 3115, a fuselage 3120, a
vertical propulsion frame 3130, vertical thrusters, collectively
3140, and a horizontal thruster 3150. In the embodiment of FIG. 31,
the wing portions 3110 are sectioned into parts, so that the
vertical propulsion frame 3130 may be inserted in a space between
its sections as an alternative to wing openings. In this
embodiment, the propulsion system is positioned between two halves
of the wing portions 3110, which are held together by the wing spar
3115. In alternate embodiments of the present invention, the wing
portions 3110 may be further subdivided into more sections with
additional space for vertical thrusters and additional wing
sections may be provided. Also, in alternate embodiments,
additional flight control surfaces may be provided on the wing
portions 3110 to control the horizontal flight path. Alternatively,
the aircraft horizontal maneuvering may be controlled using the
vertical thrusters.
[0139] FIG. 32 shows a high level diagram of an aircraft assembly
3200 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3200 of FIG. 32 includes a first
wing assembly 3210, a second wing assembly 3220, a fuselage 3230, a
vertical propulsion system, collectively 3240 and a horizontal
propulsion system, collectively 3250. In the embodiment of FIG. 32,
the vertical propulsion system 3240 includes four thrusters, while
the horizontal propulsion system includes two thrusters. The first
and second wing assemblies 3210 and 3220 may be connected by wing
extensions 3215, thus producing a closed wing configuration. The
aircraft assembly 3200 may also include landing gear (not shown)
which enables the aircraft to land and move along the ground
surface.
[0140] FIG. 33 shows a three-dimensional view of an aircraft
assembly, such as the aircraft assembly 3200 of FIG. 32, in
accordance with an embodiment of the present invention. Like the
aircraft assembly 3200 of FIG. 32, the aircraft assembly 3300 of
FIG. 33 also uses a closed wing configuration. However, instead of
two horizontal propulsion motors and propellers as in the aircraft
assembly 3200 of FIG. 32, a single motor with a propeller is used
for horizontal propulsion in the aircraft assembly 3300 of FIG. 33.
The aircraft assembly 3300 of FIG. 33 illustratively includes a
first wing assembly 3310, a second wing assembly 3320, a fuselage
3330, a vertical propulsion system, collectively 3340, a horizontal
propulsion system 3350 and landing gear 3360. The vertical
propulsion system 3340 may include four thrusters (not shown), two
in each wing, while the horizontal propulsion system may include
one pusher propeller. In an alternate embodiment of the present
invention, a pulling propeller in front of an aircraft assembly may
be used for horizontal propulsion.
[0141] In the embodiment of FIG. 33, the front (first) and back
(second) wing sections are staggered and located in different
vertical planes. The wing sections form a closed wing
configuration, where the front and back wing sections are connected
by vertical wing extensions 3315 that may also serve as vertical
stabilizers. The closed wing configuration improves the aerodynamic
performance of an aircraft, however, in various embodiments of the
present invention, the first and second wings do not have to be
connected via the wing extensions and may form other wing
configurations. For example, bi-plane and canard wing
configurations may also be suitable for a VTOL aircraft assembly in
accordance with embodiments of the present invention. In alternate
embodiments of the present invention, additional wing portions and
lift-producing surfaces may also be added for improved performance.
In such embodiments, at least some part of wing portions and
lift-producing surfaces may be mechanically flexible so that the
wing may change shape if necessary as shown in the embodiment of
FIG. 2. Alternatively or in addition, in various embodiments of the
present principles one or both wings may be separable from the
fuselage 3330, so that the fuselage 3330 or its parts may detached
from the rest of the airframe and independently transported.
[0142] In accordance with embodiments of the present invention, the
described VTOL aircraft of the present invention may be piloted and
unpiloted. In the latter case, VTOL aircraft may be an unmanned
airborne vehicle (UAV) with either an autonomous flight control
system or a remotely controlled flight control system. Flight
control systems may allow direct interactions with onboard
passengers, such as providing destination requests, flight
directions, alerts, communications and others. Flight control
systems may allow direct interactions with onboard cargo, e.g.
using electronic tags, machine-to-machine communications, and other
cargo-embedded computer systems. Such a VTOL aircraft in general
and VTOL UAV of the present invention in particular may be used for
the automated transport of cargo and passengers, especially to and
from locations that are inaccessible by other airborne aircraft. In
addition to being used for transportation, a VTOL UAV in accordance
with the present principles may be used for ground surveillance,
weather monitoring, communications and many other applications.
[0143] In accordance with embodiments of the present invention, the
described VTOL aircraft may be used for different flight modes. The
flight modes may include different forms of vertical and horizontal
transport. Vertical transport modes may include single and multiple
aircraft modes. The vertical transport may also be classified into
several categories of coordinated and uncoordinated vertical
take-off and landing, as well as vertical descent and ascent.
Similarly the horizontal transport modes may include individual
(i.e. single aircraft) flight (i.e. outside of any flight
formation) and multiple aircraft flight modes as described above.
The latter may further include uncoordinated, partly coordinated
and fully coordinated flight modes. In the uncoordinated flight
mode, each aircraft may not have to coordinate its flight plan with
any other aircraft or any flight authority. The safety of the
aircraft may be ensured either by a pilot or an onboard
collision-avoidance system (i.e. as a part of an auto-pilot onboard
of a UAV). In the partly coordinated flight mode, each aircraft may
have at least some awareness of its surroundings and capabilities
to coordinate its flight pattern with other aircraft either
directly or through a centralized flight controller. For example,
transportation systems 1200 and 1300 shown in FIGS. 12 and 13 may
also include aircraft travelling in the partly coordinated flight
mode. In the fully coordinated flight mode, the flight pattern of
each aircraft is tightly coordinated with other aircraft in the
vicinity. For example, formation flight and close formation flight
are examples of a fully coordinated flight mode.
[0144] In accordance with embodiments of the present invention, a
VTOL aircraft may use various power sources, including gas, liquid
and solid fuels, electrical batteries and supercapacitors,
regenerative and non-regenerative fuel cells, renewable power
sources, such as solar, thermal and wind energy, and others.
Various power conversion mechanisms may be used onboard, such as
electrical generation for mechanical-to-electrical transfer, solar
photovoltaics for optical-to-electrical transfer, thermovoltaics
for thermal-to-electrical, and so on. To expedite power transfer
some power modules may be swappable. For example, a depleted
battery may be swapped with a freshly charged one. In addition,
various power transfer mechanism may be used to transfer energy to
a VTOL aircraft, including airborne refueling and wireless power
beaming using optical and radio frequency beams. In such an
embodiment of the present invention, the VTOL aircraft may be
equipped with a refueling beam, high-power optical receivers and RF
antennas, respectively.
[0145] FIG. 34 shows a high level diagram of an aircraft assembly
3400 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3400 of FIG. 34 illustratively
includes wing portions, collectively 3410, a fuselage 3420, a
vertical propulsion system, collectively 3430 and a horizontal
propulsion system, collectively 3440. The fuselage 3420 may be
configured to include a cockpit, a cargo compartment and/or a
passenger cabin (not shown). As depicted in the embodiment of FIG.
34, the vertical propulsion system 3430 may include at least two
thrusters, while the horizontal propulsion system 3440 may include
two jet propulsion engines. In addition, in accordance with various
embodiments of the present invention, the aircraft assembly 3400
may include other systems such as landing gear, vertical propulsion
air vents, empennage, additional lifting surfaces, external pods
and containers, external power systems such as solar photovoltaic
modules and other systems (not shown). Furthermore, in various
embodiments of the present invention, the aircraft assembly 3400
may include various sensors for flight control systems, including
vortex sensors for enabling close formation flight (not shown).
Vortex sensors may provide information to aircraft in a formation
about the position of vortices produced by a leader aircraft in the
formation, which in turn allows the flight control system to
optimize the flight parameters of a follower aircraft for best
flight performance.
[0146] FIG. 35 shows a high level diagram of an aircraft assembly
3500 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3500 of FIG. 35 includes wing
portions, collectively 3510, a fuselage 3520, a vertical propulsion
system, collectively 3530 and a horizontal propulsion system,
collectively 3540. The fuselage 3520 may be configured to include a
cockpit, a cargo compartment and/or a passenger cabin (not shown).
As depicted in the embodiment of FIG. 35, the vertical propulsion
system 3530 may include four thrusters, while the horizontal
propulsion system 3540 may include two jet propulsion engines. In
addition, the design of the fuselage 3520 may be modular, so that
at least a section of or a whole fuselage 3520 may be separable and
can be controllably separated from the rest of the airframe.
[0147] FIG. 36 shows a high level diagram of an aircraft assembly,
such as the aircraft assembly 3500 of FIG. 35, having a detached
fuselage in accordance with an embodiment of the present
principles. The aircraft assembly 3600 of FIG. 36 depicts the wing
portions 3510 of the aircraft assembly 3500 of FIG. 35, a mounting
system 3625 for a fuselage or a section of a fuselage and the
vertical propulsion system 3530 and the horizontal propulsion
system 3540 of the aircraft assembly 3500 of FIG. 35. Similar to
the aircraft assembly 3500 of FIG. 35, the aircraft assembly 3600
of FIG. 36 may be an autonomously or remotely piloted aircraft and
thus include a flight control system (not shown) with autonomous
flight capabilities (e.g., an auto-pilot system). Additional
capabilities of the aircraft assembly 3600 may include the ability
to locate and mount a fuselage or a section of a fuselage onto its
mounting system 3625. This can be achieved for example during the
vertical descent of the aircraft assembly 3600 while the fuselage
or its section is positioned on the ground.
[0148] Mounting system 3625 may include different mechanisms for
attaching the fuselage 3520. For example, FIG. 36 shows flat
horizontal bars as part of the mounting system 3625. These bars may
act as both the load-bearing spars for the airframe and the
suspension system for the fuselage 3520. They may be either fixed
or mobile. In the latter case, the bars may be either retractable
into the body of the aircraft assembly 3600, rotatable around a
pivot point on the aircraft assembly 3600, or otherwise movable to
allow free movement of the fuselage 3520 into and out of the
aircraft assembly 3600 in either the vertical or the horizontal
direction. The fuselage 3520 may have elements in its hull (e.g.
holes or openings) that are mated and can be affixed to the
mounting system 3625.
[0149] FIG. 37 shows a high level diagram of a cargo pod (or
similarly an HO pod) 3700 in accordance with an embodiment of the
present principles. The cargo pod 3700 of FIG. 37 can be attached
to the aircraft 3600 as a part of its fuselage using the mounting
system 3625. As depicted in FIG. 37, the cargo pod 3700 may include
a pod frame 3710, a cabin 3720 and a ground transport system 3730.
The cabin 3720 may be used to transport cargo and passengers. The
ground transport system 3730 may include wheels and powertrain (not
shown) providing the capabilities to drive the cargo pod 3700 on
the ground surface. In accordance with various embodiments of the
present invention, the ground transport system 3730 may be driven
by a passenger, remotely or autonomously using an autonomous
driving computer system (not shown) on board the cargo pod 3700. In
various embodiments, the ground transport system 3730 may also be
separable from the rest of the cargo pod 3700, so that it can
separate and remain on the ground after the cargo pod 3700 is
mounted onto an aircraft assembly in accordance with the present
principles.
[0150] FIG. 38 shows a high level schematic diagram of a loading
method 3800 in accordance with an embodiment of present invention.
The loading method 3800 of FIG. 38 depicts an example of using an
aircraft like the aircraft assembly 3600 of FIG. 36 and a cargo pod
like the cargo pod 3700 of FIG. 37 in accordance with embodiments
of the present invention. The loading method 3800 of FIG. 38 can be
considered as a modified loading method of FIG. 6. In the
embodiment of a loading method 3800 of FIG. 38, an area on the
ground 3810 is used to locate a cargo pod 3820 using a VTOL
aircraft 3830 of embodiments of the present invention. In the
embodiment of FIG. 38, different ground transportation means may be
used to transport the cargo pod 3820 on the ground before loading
and mounting to an aircraft assembly of the present invention. Such
ground transportation means may include built-in means (e.g.,
self-propulsion) and assisted means (e.g. specialized ground
transport vehicles for cargo pods). In accordance with various
embodiments of the present invention, before landing and loading,
the VTOL aircraft 3830 may have an open bay area (not shown) in its
fuselage mounting system. Upon landing or while hovering in a
stable position above the cargo pod 3820, the VTOL aircraft 3830
may attach the pod to its mounting frame as a part of its fuselage
and assume a new aircraft configuration 3835, in which the cargo
pod 3820 is now a part of the VTOL aircraft and in one embodiment
part of its fuselage. In alternate embodiments of the present
invention, other mounting approaches in differently situated bay
areas on an aircraft assembly of the present invention may be
implemented using the loading method 3800 of FIG. 38.
[0151] The loading method 3800, and similarly an unloading method
defined as its reverse process, may involve either vertical or
horizontal motion of either the aircraft 3830 or the cargo pod
3820, or both. For example, the cargo pod 3820 may be situated on
the ground and kept motionless, while the aircraft 3830 may be
moving vertically down or up during loading or unloading,
respectively. Alternatively, the aircraft 3830 may land and be
stationary on the ground, while the cargo pod may move horizontally
into and out of the mounting frame during loading and unloading. In
addition, the loading and unloading may include affixing and
securing of the cargo pod to the mounting frame using fastening
hardware, such as latches, clamps, bolts, locks, braces etc.
[0152] FIG. 39 shows a high level diagram of an aircraft assembly
3900 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 3900 of FIG. 39 includes wing
portions, collectively 3910, a fuselage frame 3920 and cargo pods,
collectively 3930. In the embodiment of FIG. 39, the cargo pods
3930 may be loaded and unloaded individually and independently from
each other, so that different cargo and passengers may be loaded
and unloaded at several different locations. In addition, cargo
pods may be loaded into other parts of the aircraft assembly 3900,
such as wings and tails, and attached as standalone units to a
fuselage, wings or a tail. In accordance with the present
invention, an aircraft fuselage may be segmented into multiple
sections and thus contain multiple cargo pods.
[0153] FIG. 41 shows a high level diagram of an aircraft assembly
4100 in accordance with an alternate embodiment of the present
invention. The aircraft assembly 4100 includes wing portions,
collectively 4110, a fuselage portion 4120, a vertical propulsion
system, collectively 4130, and a horizontal propulsion system,
collectively 4140. The fuselage 4120 may be configured to include a
cockpit, a cargo compartment and/or a passenger cabin, as shown in
FIG. 41. As depicted in the embodiment of FIG. 41, the vertical
propulsion system 4130 may include four thrusters, while the
horizontal propulsion system 4140 may include two jet propulsion
engines, pusher propeller engines or similar propulsion systems. In
addition, the design of the fuselage 4120 may be modular, so that
at least a section of or the entire fuselage 4120 may be separable
and can be controllably separated from the rest of the airframe. In
addition to the detachable fuselage section 4120, the fuselage may
include fuselage mounting latches, collectively 4160, which may be
used to affix the detachable fuselage section 4120 to the open
frame portion of the aircraft assembly 4100.
[0154] FIG. 42 shows a separated fuselage section 4120 of the
aircraft assembly 4100, otherwise known as a pod. The pod 4120 may
include an outer shell 4210, a cockpit 4220, and mounting locks,
collectively 4230. The pod 4120 may further include additional
hatches and doors for loading and unloading cargo and passengers
into the pod. It may also include gear and equipment to facilitate
the operation of the aircraft assembly as a whole and the fuselage
section as a standalone unit. In the former case, the
instrumentation may include sensors, such as video cameras for
providing accurate information on relative positioning between the
pod 4120 and the rest of the aircraft assembly 4100 during the
loading and unloading procedures, and an accurate positioning
system including actuators and autonomous controls for relative
positioning of the pod 4120 with respect to the airframe 4100. In
the latter case, the additional equipment may include landing gear
and autonomous means of ground transportation. The landing gear may
range from a set of retractable wheels to a cargo-grade parachute.
In the latter case the unloading procedure could occur in
midflight, where the pod may be detached and delivered to the
ground without landing the aircraft.
[0155] FIGS. 43 and 44 depict alternate embodiments of the pod 4120
in accordance with the present invention. For example, FIG. 43
shows an integrated mobile pod 4300, which consists of a pod shell
4310, a cockpit (alternatively a passenger compartment or a cargo
space with a hatch) 4320, independent transportation means
including at least a set of wheels 4330 and mounting locks,
collectively 4340. Apart from the wheels, the transportation means
may include engines, motors, transmission gears, fuel tanks,
batteries, brakes, steering wheels, self-driving computer systems
and similar equipment. Alternatively, FIG. 44 shows a hybrid pod
4400, which may consist of a pod shell 4410, a passenger or cargo
compartment 4420 and mounting locks, collectively 4440. In some
embodiments, by itself, the pod 4400 may lack independent means of
transportation. However, the pod 4400 may be mounted on to a mobile
platform 4450 while on the ground. The platform 4450 may include
different means of transportation including a set of wheels 4430 as
shown in FIG. 44. In addition, the platform may be equipped with
engines, motors, transmission gears, fuel tanks, batteries, brakes,
steering wheels, remotely driven and autonomous self-driving
computer systems and similar equipment.
[0156] FIG. 45 shows a high level diagram of an aircraft 4500 in
accordance with another embodiment of the present invention. The
aircraft 4500 includes wing portions, collectively 4510, an open
fuselage portion 4520, a vertical propulsion system, collectively
4530, and a horizontal propulsion system, collectively 4540. The
open fuselage portion 4520 may include a mounting frame for
attaching payload pods carrying cargo and passengers. The mounting
frame in turn may include a crossbar 4525, as shown in FIG. 45. The
cross-bar 4525 may be a load bearing structural element and serve
the purpose of maintaining structural integrity of the aircraft
4500 in the absence of the payload pods. The cross-bar 4525 may
comprise multiple cross-bars located in different areas of the open
fuselage portion 4520. Furthermore, it may be movable, retractable
or foldable, so that for example it could be retracted to allow
loading and unloading of the payload pods. The open fuselage
portion 4520 may be in the aft portion of the aircraft 4500, as
shown in FIG. 45, or alternatively in the middle or fore portions
of an aircraft.
[0157] FIG. 46 shows the front (upper figure) and top (lower
figure) views of an aircraft assembly 4600 in accordance with
another embodiment of the present invention. The aircraft assembly
4600 includes wing portions, collectively 4610, a modular fuselage
portion 4620, a vertical propulsion system, collectively 4630, and
a horizontal propulsion system, collectively 4640. The modular
fuselage portion 4620 may be a payload pod detachable from the rest
of the assembly 4600. As depicted in the embodiment of FIG. 46, the
pod 4620, when mounted, may define at least a portion of the outer
airframe of the aircraft assembly 4600. That is, the pod 4620 may
define a shape of at least a portion of the aircraft assembly
4600.
[0158] As depicted in FIG. 46, the aircraft assembly 4600 may
include a mounting frame for attaching payload pods carrying cargo
and passengers. The mounting frame in turn may include a crossbar
4625, as shown in FIG. 46. The cross-bar 4625 may be a load bearing
structural element and serve the purpose of maintaining structural
integrity of the aircraft 4600. The cross-bar 4625 may be located
in different areas of a fuselage. Furthermore, it may be fixed and
shaped to fit the shape of the payload pod 4620. For example, FIG.
46 shows the cross-bar 4625 in a shape of an upward arch, which
closely follows the shape of the payload pod 4620. As result, the
payload pod 4620 may be loaded and unloaded from the aircraft
assembly 4600 without removing the crossbar 4625. The cross-bar
4625 and other parts of the airframe may include latches for
securing and holding the payload pod in place.
[0159] FIG. 47 shows a high level diagram of an aircraft assembly
4700 in accordance with another embodiment of the present
invention. The aircraft assembly 4700 includes wing portions,
collectively 4710, an open fuselage portion 4726 in the front of
the assembly, a payload pod 4720, and a vertical propulsion system,
collectively 4730. In addition, it may optionally include a
horizontal propulsion system. Alternatively, the vertical
propulsion system 4730 may also serve as a horizontal propulsion
system, for example by rotating its vertical thrusters into a
horizontal position. The aircraft assembly 4700 may include a
mounting frame for attaching payload pods carrying cargo and
passengers. The mounting frame in turn may include a crossbar 4725,
as shown in FIGS. 47 and 48 shaped as an arch to follow the
contours of the upper portion of the payload pod 4720. The aircraft
assembly 4700 as a whole and the payload pod 4720 may be shaped so
as to minimize aerodynamic drag and improve performance in flight.
The fixed portion of the fuselage may be shaped to provide low
aerodynamic drag both for flying with and without the payload pod
4720 attached to the airframe. The pod 4720 may be individually
shaped that, when mounted, adds to the aerodynamic properties of
the aircraft assembly 4700 by, for example, providing reduced
aerodynamic drag or increased lift during flight. This may be
achieved by designing and making the shapes of the outer surface of
the pod 4720 and the rest of the airframe of the aircraft assembly
4700 to form a continuous and aerodynamically efficient shape. For
example, this could ensure that there are no large air gaps and
openings between the pod 4720 and the open fuselage portion in the
aircraft assembly 4700, thus preventing additional parasitic
aerodynamic drag. Furthermore, this may be done to improve the
airflow around the aircraft assembly 4700 with the pod 4720
attached in such a way as to increase the lift force during the
horizontal flight, for example in the case where the pod 4720 may
form a continuous surface with the wing 4710.
[0160] Furthermore, FIG. 48 shows two front views of the aircraft
assembly 4700, in which the top figure shows the assembly with the
payload pod 4720 attached and the bottom figure shows the assembly
with the payload pod 4720 detached. Both configurations are shown
in on-the-ground positions, where the aircraft may be standing and
moving using landing gear 4712. The landing gear 4712 may be
retractable during the flight. In addition, the payload pod 4720
may be equipped with its own landing gear 4722, which could be used
for independent transportation of the payload on the ground while
it's detached from the aircraft assembly 4700. As described above
with respect to FIG. 46, the payload pod 4720, when mounted, may
define at least a portion of the outer airframe of the aircraft
assembly 4700. That is, the pod 4720 may define a shape of at least
a portion of the aircraft assembly 4700.
[0161] FIG. 49 shows a high level diagram of an aircraft assembly
4900 in accordance with another embodiment of the present
invention. The aircraft assembly 4900 includes a wing portion 4910,
a payload pod 4920, and a horizontal propulsion system,
collectively 4930. The payload pod may include a hatch 4921 for
loading and unloading of cargo and passengers. The aircraft
assembly 4900 may include an open airframe portion and a mounting
frame for attaching the payload pod 4920. FIG. 50 further
illustrates the aircraft assembly 4900 in a detached state, showing
the aircraft 5000 capable of independent flight and a separated
payload pod 4920. The aircraft 5000 may include a flight control
system for remote or autonomous flight. Alternatively or
additionally, it may include a piloted cockpit with manual flight
controls providing independent flight capability for the aircraft
5000.
[0162] FIG. 51 shows a high level diagram of an aircraft 5100 in
accordance with another embodiment of the present invention. The
aircraft 5100 includes a wing portion 5110, an open fuselage
portion 5120, and a horizontal propulsion system, collectively
5130. The open fuselage portion 5120 may include a mounting frame
for attaching payload pods carrying cargo and passengers. The open
fuselage portion 5120 may be in the fore portion of the aircraft
5100, as shown in FIG. 51, or alternatively in the middle or fore
portions of an aircraft. The airframe of the aircraft 5100 may be
strengthened in order to provide the structural integrity and
mechanical strength around and near the open fuselage portion 5120.
The airframe strengthening can be accomplished using spars and
other load-bearing structural elements made from lightweight
composite materials, such as for example carbon fiber materials.
Furthermore, the aircraft 5100 may have a center-of-gravity (CG)
position control system for dynamic adjustment of the aircraft 5100
CG position on the ground and in flight. The CG position control
system may include for example a number of containers, collectively
5140, interconnected via pipes, collectively 5145, and pumps (not
shown). The containers 5140 may contain fluid that could be
transferred through the pipes 5145 using the pumps and thus shift
the aircraft CG in the direction of the fluid transfer. The fluid
may be a ballast fluid, such as water, or fuel, such as benzene or
kerosene.
[0163] FIG. 52 shows a high level diagram of an aircraft 5200 in
accordance with another embodiment of the present invention. The
aircraft 5200 includes a wing portion 5210, an open fuselage
portion 5220, and a horizontal propulsion system, collectively
5230. Furthermore, similar to the aircraft 5100, the aircraft 5200
may have a center-of-gravity (CG) position control system,
collectively 5240, for dynamic adjustment of the aircraft 5200 CG
position on the ground and in flight. The CG position control
system 5240 may include for example a number of ballast weights,
collectively 5242, attached to a suspension frame, collectively
5244. The suspension frame 5244 may be used to shift the position
of the ballast weights 5242 and thereby shifting the CG of the
aircraft 5200. The suspension frame may include gears and actuators
enabling it to expand and/or contract its different portions, as
shown in FIG. 52. The ballast weights 5242 may include different
elements of the aircraft 5200, such as batteries, flight control
systems, payload pods, communication systems and others. The CG
position control systems, such as those on the aircraft 5100 and
5200, may be used for example after loading and unloading of
payload pods. For example, the addition of a payload pod may shift
the CG of an aircraft assembly in such a way as to make it unstable
and difficult to control in flight. Therefore, the CG position
control system could be used to compensate at least in part the CG
shifts due to loading and unloading of payload pods. Furthermore,
it could also be used in other situations, such as during a
transition between the vertical and horizontal flight modes, in
which the locations for a more stable CG position during flight may
differ and should be adjusted dynamically.
[0164] FIG. 53 shows a high level diagram of an aircraft 5300 in
accordance with another embodiment of the present invention. The
aircraft 5300 includes a wing portion 5310, an open fuselage
portion 5320, vertical propulsion system, collectively 5330, and a
horizontal propulsion system, collectively 5340. Both the vertical
and horizontal propulsion systems may include propeller-based
thrusters driven by electric motors or gas-powered engines. The
aircraft 5300 may also utilize flight control surfaces, such as
ailerons 5350, for controlling the horizontal flight. In addition,
the open fuselage portion 5320 may include a mounting frame 5360
for attaching payload pods, which may comprise latches and braces
for securing the pods in place.
[0165] FIG. 54 shows the top and side views of a payload pod 5400
that can be attached to the aircraft 5300. The shape of the payload
pod 5400 is matched to the shape of the open fuselage portion 5320,
so that when the payload pod 5400 is mounted, the combined aircraft
assembly has a continuous aerodynamically shaped body with smooth
surfaces optimized for low aerodynamic drag during the horizontal
flight. In addition, the payload pod 5400 may have an opening hatch
5410 for loading and unloading cargo. Furthermore, the payload pod
5400 may have a series of latches 5420 to be used for attaching to
the mounting frame 5360. Either the mounting frame 5360, or the
latches 5420, or both may have actuators enabling the remote
control of the loading and unloading of the payload pod 5400 onto
the aircraft 5300.
[0166] Similarly, FIG. 55 shows a high level diagram of an aircraft
5500 in accordance with another embodiment of the present invention
and FIG. 56 shows the top and side views of a matching payload pod
5600. The aircraft 5500 includes a wing portion 5510, an open
fuselage portion 5520, vertical propulsion system, collectively
5530, and a horizontal propulsion system, collectively 5540. The
aircraft 5500 may also include flight control surfaces,
collectively 5550, for controlling the horizontal flight of the
aircraft 5500. In addition, the open fuselage portion 5520 may
include a mounting frame for attaching payload pods, which may
comprise a mounting bar 5560 and a latch 5565. The payload pod 5600
may in turn include a matching groove 5610 and a mounting lock
5620, to match the mounting bar 5560 and the latch 5565 on the
aircraft 5500, respectively. Optionally, the latch 5565 may be
remotely actuated to enable remote and automatic drop-off of the
payload pod 5600.
[0167] FIG. 57 shows a high level diagram of an aircraft 5700 in
accordance with another embodiment of the present invention. The
aircraft 5700 includes a fixed portion of a fuselage 5710, an open
portion of a fuselage 5720, a vertical propulsion system,
collectively 5730, and a payload pod mounting system, collectively
5740. In addition, the aircraft 5700 may include a flight control
system 5750, providing either remote or autonomous piloting
capabilities. The vertical propulsion system is designed to provide
sufficient lift for both the aircraft 5700 and its payload.
[0168] FIG. 58 shows the aircraft assembly 5800, comprised of the
aircraft 5700 and its payload pod 5870. The payload pod and its
mounting system may be designed using any of the embodiments
described above. In addition, other objects and vehicles could
serve as payload pods, including and not limited to cargo
containers, postal packages, passenger cars, motorcycles, other
aircraft, boats other water-born vessels. In the case of water-born
payload pods, the aircraft assembly may have capabilities to land
on and take-off from a water surface.
[0169] FIG. 59 illustrates three different examples of mounting a
payload onto the aircraft assembly 5800: top position 5801, middle
position 5802 and bottom position 5803. In this case the exemplary
payload pod is a car, but it may be any other type of the payload
pod described above. In the two positions 5801 and 5803, top and
bottom positions respectively, the open fuselage portion 5520 may
be partially or fully closed. For example, the fuselage portion may
be instead a load-bearing platform, which may be used to hold and
carry payload pods as a part of the payload mounting frame.
[0170] FIG. 60 shows the bottom (upper figure) and front (lower
figure) views of an aircraft assembly 6000 in accordance with
another embodiment of the present invention. The aircraft assembly
6000 includes a wing portion 6010, a modular payload pod 6020, a
vertical propulsion system, collectively 6030, and a horizontal
propulsion system, collectively 6040. The payload pod 6020 may be
attached to and detached from the rest of the aircraft assembly
6000 using a mounting frame 6025. Instead of an open airframe
portion, the mounting frame 6025 may be attached to a fully closed
airframe portion as shown in FIG. 60. At least a part of the
payload pod 6020 may be shaped to match the shape of the mounting
frame and at least a portion of the airframe of the aircraft
assembly 6000. That is, the payload pod 6020, when mounted, may
define at least a portion of the outer airframe of the aircraft
assembly 6000. That is, the payload pod 6020 may define a shape of
at least a portion of the aircraft assembly 6000. In addition, the
combined shape of the aircraft assembly 6000, including the payload
6020, pod may be shaped to provide minimal aerodynamic drag during
horizontal flight by, for example, providing reduced aerodynamic
drag or increased lift during flight. The vertical and horizontal
propulsion systems may utilize different thrusters, including but
not limited to propeller-based and jet-engine based thrusters.
[0171] While the foregoing is directed to embodiments of the
present invention, other and further embodiments of the invention
may be devised without departing from the basic scope thereof.
* * * * *