Note: Descriptions are shown in the official language in which they were submitted.
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AIR TRANSPORTABLE FUEL CELL POWER SYSTEM
TECHNICAL FIELD
[0001] The present generally concerns fuel cell powered unmanned aerial
vehicles (UAVs), and more particularly to using such UAVs as air transportable
power systems for remote field use.
BACKGROUND
[0002] The commercial market for small UAVs, or drones, used in civil
applications is expected to increase dramatically over the next few years. In
addition
to military applications, many new uses for UAVs are being announced
regularly.
Currently, well-known uses include parcel delivery, disaster response, hydro
and rail
line inspections, flare stack inspections, precision agriculture, search and
rescue
missions, and film production. However, it is well known that battery powered
UAVs
have very limited flight times due to the relatively low specific energy (Watt-
hours/kg)
of existing rechargeable battery technologies.
[0003] Fuel cell systems for UAV applications offer much higher specific
energies
than lithium polymer (LiPo) batteries and therefore provide a significant
increase in
flight endurance for small, electrically powered UAVs. Indeed, fuel cell
systems can
provide up to 3 to 4 times the specific energy of LiPo batteries when using
compressed hydrogen gas as fuel. Even higher specific energy is available
using
other forms of hydrogen fuel.
[0004] The inventors are unaware of any UAV fuel cell system, which can
also be
used for a practical ground power source that is air transportable. Moreover,
if
additional hydrogen fuel could be made available or carried to the field by
the user,
the overall system specific energy available at the remote onsite location
would
increase dramatically.
[0005] Thus, there is an unmet need for an easily transportable energy
source to
remote locations such that in combination with a fuel supply located at the
remote
location, substantially increased energy can be provided for a prolonged
period.
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BRIEF SUMMARY
[0006] We
have addressed the aforesaid problems by developing a new and
unobvious system and method, which significantly reduces the weight burden of
a
field power source by eliminating the need to carry it. This advantageously
provides
sufficient onsite power and energy to make it practical for field use. In
essence, our
air transportable fuel cell power system can fly to a specific remote
location, land,
and then be configured by the user to supply power on the ground. When the
power
system is no longer needed in the field, it is then reconfigured to provide
power to fly
the UAV, which can then move to the next location or return to base. Our
system
substantially reduces, or essentially eliminates, the weight burden of a field
power
supply by providing an air transportable power source. This dramatically
increases
specific energy compared to rechargeable batteries, which allows significantly
longer
run times in the field.
[0007]
Accordingly, in one embodiment there is provided a system for delivering a
power source to a remote location, the system comprising:
[0008] an
unmanned aerial vehicle (UAV) having a primary power system
connected thereto for flying the UAV to the remote location, the UAV being
autonomously controlled, the primary power system being capable of being
converted to a secondary power system to provide a power source at the remote
location; and
[0009] a
controller in communication with the UAV to operate the UAV and to fly
the UAV to the remote location.
[00010] In one example, a fuel source with an amount of fuel is delivered to
the
remote location so as to be connected to the secondary power source. The fuel
source is gaseous hydrogen. The fuel source is liquid hydrogen. The fuel
source is a
chemical hydride. The fuel source is a metal hydride. The fuel source is
generated at
the remote location.
[00011] In one example, the fuel source includes about 8 kg energy storage
mass
in the form of a hydrogen fuel source, the 8 kg providing about 480 grams of
usable
hydrogen. A 50% fuel cell system efficiency (typical) with the specific energy
of
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hydrogen fuel being 33,410 Wh/kg, the energy available would be 0.480 kg *
33,410
Wh/kg * 0.5 = 8018.4 Wh,
[00012] Accordingly, in another embodiment, there is provided a method for
delivering a power source to a remote location, the method comprising:
[00013] receiving a signal from a controller;
[00014] flying an unmanned aerial vehicle (UAV), having a primary power system
connected thereto, for powering the UAV to the remote location, the UAV being
autonomously controlled; and
[00015] converting the primary power system into a secondary power system for
providing a power source at the remote location.
[00016] In one example, a fuel source with an amount of a fuel is delivered to
the
remote location so as to be connected to the secondary power source. The fuel
source is gaseous hydrogen. The fuel source is liquid hydrogen. The fuel
source is a
chemical hydride. The fuel source is a metal hydride. The fuel source is
generated at
the remote location.
[00017] In one example, the fuel source includes about 8 kg energy storage
mass
in the form of a hydrogen fuel source, the 8 kg providing about 480 grams of
usable
hydrogen. A 50% fuel cell system efficiency (typical) with the specific energy
of
hydrogen fuel being 33,410 Wh/kg, the energy available would be 0.480 kg *
33,410
Wh/kg * 0.5 = 8018.4 Wh,
[00018] Accordingly, in yet another embodiment, there is provided an apparatus
for
autonomously powering a UAV to a remote location, the apparatus comprising;
[00019] a lightweight frame;
[00020] landing gear connected to the frame;
[00021] a propulsion system connected to the frame;
[00022] a primary power source connected to the propulsion system, the primary
power system being capable of being converted to a secondary power system to
provide a power source at the remote location; and
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[00023] an integrated field power system to receive therein the secondary
power
system, the integrated field power system being in communication with the
propulsion system.
[00024] In one example, the system described above further includes an
integrated
field power system to receive therein the secondary power system, the
integrated
field power system being in communication with the propulsion system.
[00025] Accordingly, in another embodiment, there is provided a method of
actively
deploying one or more unmanned aerial vehicles (UAVs) using a non-transitory
computer readable medium having stored therein instructions that are
executable to
cause a controller to activate deployment of one or more unmanned aerial
vehicles
(UAVs), the method comprising:
[00026] receiving, via an integrated field power system interface of an air
transportable fuel cell power system, a first input that corresponds to a
first request
for a first power source, which first power source is capable of being
converted to a
second power source and in which the first power source is needed by a
requester at
a first location remote from a first UAV fuelling station; and
[00027] in response to receipt of the first input, sending, via a network
interface,
the first request for the first power source to a network of the one or more
UAVs that
are adapted to carry the first power source based on the requester located at
the first
remote location, the requester notifying the controller of a need for the
first power
source at the first remote location, the requester having a requester account,
wherein the first request for the first power source includes:
a. a unique electronic identifier for the air transportable fuel cell power
system, wherein the unique electronic identifier is indicated by the requester
account;
b. an indication of the type of power source needed at the first location:
and
[00028] a request for delivery of the first power source by the one or more
UAVs to
the remote location associated with the unique electronic identifier according
to the
requester account.
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BRIEF DESCRIPTION OF THE DRAWINGS
[00029] These and other features of that described herein will become more
apparent from the following description in which reference is made to the
appended
drawings wherein:
[00030] FIG. 1 is a perspective view of an embodiment of an air transportable
fuel
cell power system;
[00031] FIG. 2 is a front view of the air transportable fuel cell power system
of
FIG. 1 showing detail of the integrated field power system interface;
[00032] FIG. 3 is a perspective top view of the air transportable fuel cell
power
system of FIG. 1, showing an alternative integrated field power system
interface
connected to an external power manager;
[00033] FIG. 4 is a perspective top view of the external power manager of FIG.
3,
connected to number of pieces of field equipment;
[00034] FIG. 5 is a perspective top view of a fixed wing UAV for carrying air
transportable power system for remote field use;
[00035] FIG. 6 is a perspective top view of a hybrid vertical take-off and
landing
(VTOL) fixed wing UAV for carrying the air transportable power system; and
[00036] FIG. 7 is simplified block diagram showing a communications network.
DETAILED DESCRIPTION
Definitions
[00037] Unless otherwise specified, the following definitions apply:
[00038] The singular forms "a", "an" and "the" include corresponding plural
references unless the context clearly dictates otherwise.
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[00039] As used herein, the term "comprising" is intended to mean that the
list of
elements following the word "comprising" are required or mandatory but that
other
elements are optional and may or may not be present.
[00040] As used herein, the term "consisting of' is intended to mean including
and
limited to whatever follows the phrase "consisting of". Thus, the phrase
"consisting
of" indicates that the listed elements are required or mandatory and that no
other
elements may be present.
[00041] As used herein, the term "unmanned aerial vehicle (UAV)" is intended
to
mean either an autonomous or a semi-autonomous vehicle capable of flight
without
a physically present human pilot. Examples of flight-related functions
include, but are
not limited to, sensing the UAV's environment or operating in the air without
a need
for input from an operator. In the case of a semi-autonomous vehicle, a remote
human operator could control some functions, while other functions are carried
out
autonomously. Also, a UAV may be configured to allow a remote operator to take
over functions that can otherwise be controlled autonomously by the UAV.
Certain
functions may be controlled remotely in one instance and performed
autonomously
in another instance. For example, a remote operator could control high level
navigation decisions for a UAV, such as by specifying that the UAV should
travel
from one location to another, while the UAV's navigation system autonomously
controls more fine-grained navigation decisions, such as the specific route to
take
between the two locations, specific flight controls to achieve the route and
avoid
obstacles while navigating the route, and so on.
[00042] A UAV can be of various forms. For example, a UAV may take the form of
a rotorcraft such as a helicopter or multi-copter; a fixed-wing aircraft, a
hybrid VTOL
fixed wing aircraft, a jet aircraft, a ducted fan aircraft; a lighter-than-air
dirigible such
as a blimp or steerable balloon; a tail-sitter aircraft, a glider aircraft, or
an ornithopter.
The term "UAV" may also include the terms "drone", "unmanned aerial vehicle
system" ("UAVS"), or "unmanned aerial system" ("UAS").
[00043] Referring now to FIG. 1, a system for delivering a power source, such
as
hydrogen fuel cell, to a location that is remote from a fueling station (not
shown) is
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shown generally at 10. The system 10 is, in essence, an air transportable fuel
cell
power system. Broadly speaking, the air transportable fuel cell power system
10
comprises a fuel cell system 12, a hydrogen power source 14; a UAV 11, which
includes a UAV airframe 16, a propulsion system 18, and a landing gear 20; and
an
integrated field power system interface 21. In one example, the air
transportable fuel
cell power system 10 can travel autonomously. During flight from the fuelling
station
to the remote location, the fuel cell system 12 uses the hydrogen source 14 as
fuel.
The energy produced by the hydrogen fuel cell powers the propulsion system 18
so
that the UAV 11 transports its own power source to a specific location remote
from
the fuelling station. Upon arrival, the UAV 11 lands using the landing gear 20
and is
then reconfigured to provide power through the integrated field power system
interface 21. The ability to transport an otherwise bulky and heavy power
source
from a starting point to a finishing point remote therefrom is particularly
advantageous. One particularly desirable use example contemplated by the
inventors would be the delivery of a power source to a soldier operating in
the field.
The use of the system 10 would negate the soldier having to carry a bulky and
heavy
power source, usually on his back, to a remote location.
[00044] Referring now to FIG. 2, the air transportable fuel cell power system
10 is
shown providing more detail of the integrated field power system interface 21.
Upon
arrival at its destination, the air transportable fuel cell power system 10
can be
reconfigured to provide auxiliary power through the integrated field power
system
interface 21. Desirable power sources may include, but are not limited to,
alternating
current (AC) power through AC power receptacle 22, direct current (DC) power
at
various voltages such as 5V, 12V and 24V through DC power receptacle 24 which
could use a multitude of connector configurations, and a USB connection for
charging various electronic devices, known to those skilled in the art, at a
USB
receptacle 26.
[00045] Referring now to FIG. 3, an alternative air transportable fuel cell
power
system 50 is illustrated and includes a different integrated field power
system
interface 21 with a plurality of connections 52, which can interface through
an
electrical interface cable 54 to an external portable power manager 56. The
external
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portable power manager 56, also known as a soldier power manager, or squad
power manager, is used extensively in the military. This permits a number of
military
applications, and has the following advantages:
- Manages and prioritizes battery usage
- Powers man-packable gear and man-worn gear
- Recharges military and commercial batteries
- Optimizes solar/alternative power sources
- Monitors power sources and loads, alerting war fighter to problems
- Dynamically adjusts to changing mission needs
- Fully submergible for use in all weather
- Data logging for mission analysis and planning
[00046] Referring now to FIG. 4, a soldier's equipment configuration is shown
generally at 100. As described above, the external portable power manager 56
is
located at the centre of the configuration 100 and is electrically connected
to the air
transportable fuel cell power system 50 (not shown in FIG. 4), drawing power
from
fuel cell system 12 through the integrated field power system interface
connections
52 as best illustrated in FIG. 3. The external portable power manager 56 can
power
and charge field equipment including, but not limited to, VHF radio 102,
Multiband
Inter/Infra Team Radio (MBITR) 104, Defense Advanced GPS Receiver (DAGR)
106, infrared night vision goggles 108, and various military battery
configurations
such as a rechargeable lithium-ion battery BB-2590 110, or a rechargeable
lithium-
ion battery BB-2557 112.
[00047] Referring now to FIG. 5, an alternative UAV aircraft configuration for
the
air transportable fuel cell power system is shown generally at 150. In this
example,
the UAV is a fixed wing UAV and includes a UAV fuselage 152 that houses the
fuel
cell 12 and the integrated field power system interface 21 (not shown). UAV
wings
154, to which are attached two winglets 156, are also connected to the UAV
fuselage
152. A propulsion system 158 is located rearwardly to drive the aircraft
forwards.
[00048] Referring now to FIG. 6, in which another alternative UAV aircraft
configuration for the air transportable fuel cell power system is shown
generally at
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200. This aircraft is a hybrid VTOL fixed wing UAV. The UAV fuselage 202
houses
the fuel cell 12 and the integrated field power system interface such as 21
(not
shown). The UAV wings 204, attached to winglets 206, are also fastened to UAV
fuselage 202. The aircraft is driven forward using the propulsion system 208.
For a
vertical take-off, the propulsion system 210, attached to UAV wings 204, lifts
the
aircraft vertically to a safe height whereby the aircraft transitions to
straight and level
flight using thr propulsion system 208. Similarly for a vertical landing, the
propulsion
system 210, attached to the UAV wings 204, lowers the aircraft vertically in
order to
land the UAV.
[00049] Referring to FIG. 7, is a simplified block diagram illustrating
components of
a UAV request communications network 300, an integral part being a non-
transitory
computer readable medium having stored therein instructions that are
executable to
cause the controller to activate deployment of one or more of the unmanned
aerial
vehicles (UAVs) 312. In operation, the integrated field power system interface
302 of
an air transportable fuel cell power system, receives a first input that
corresponds to
a request for a first power source, in which first power source is capable of
being
converted to a second power source and in which the first power source is
needed
by a requester, such as a soldier located remote from the UAV fuelling
station. The
requester has a requester account and a unique electronic identifier, known
collectively as user data 308. Once the first input is received, the system
sends via a
network interface 304, the first request for the first power source to
dispatcher 306
and then to a deployment system 310 which triggers deployment of the one or
more
UAVs 312 that are adapted to carry the first power source based on the
requester
located at the first remote location. The requester indicates the type of
power source
needed at the first location and requests delivery of the first power source
by the one
or more UAVs to the remote location associated with the unique electronic
identifier
according to the requester account.
[00050] In one example, an air transportable fuel cell power system, like the
ones
described above, may include one or more UAVs located either at a single
station or
distributed over a wide geographic area. A controller communicates with the
system
to activate same at short notice. Controllers such as hand-held electronic
devices
such as mobile phones, tablets and the like can be operated either by the
person
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located remote from the station, and in need of power, or by others. Depending
on
the power needs at the remote location, the system can dispatch an appropriate
UAV or UAVs to the remote location in order to provide power.
[00051] In particular, in a military operation where power might be needed for
communications or logistics, a power system may include a fleet or "swarm"
with a
number of different types of UAVs, which are configured for different power
needs.
For instance, some UAVs may be configured with fuel cells. In particular, the
fuel
cells may themselves be further configured with various military connector
interfaces
for equipment such as a soldier power manager previously described, or to
attach
directly to the soldier's equipment itself to power or charge as required.
[00052] Due to their size and maneuverability, UAVs may be able to reach the
remote location and provide energy more quickly than traditional responses.
[00053] Typically, the equivalent specific energy levels over 1000 Wh/kg are
achievable, and even higher depending on how much hydrogen fuel can be carried
to the field.
[00054] As an example taken from the military, a typical soldier must carry up
to 8
kg of lithium ion batteries on a mission in order to power communication
equipment,
sensors, optics, targeting devices, and the like. The specific energy of a
typical
lithium ion battery is about 200 Wh/kg, which therefore provides a total of
1600 Wh
of useable energy to the soldier.
[00055] For comparison, an air transportable fuel cell power system may have
1800 Wh on board to provide energy for propulsion. With this energy, a
multirotor
aircraft can fly over 3 hours and 30 minutes. At a flight speed of 10 m/s (36
km/h),
which is typical for this type of UAV, it would travel almost 120 km. This is
significantly further than most soldier missions, and therefore would not be a
limitation on how far the soldier could travel before restocking his or her
supplies.
Further, since the UAV can travel autonomously, it would not have to follow
the
soldier directly thereby maintaining the soldier's safety by protecting their
location. If
a fixed wing, or hybrid VTOL fixed wing UAV configuration was used, even
greater
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distances could be travelled (up to 600 km) with higher amounts of energy
available
on the ground.
[00056] If the soldier carried the same 8 kg energy storage mass as hydrogen
fuel
storage (i.e. compressed gas cylinder), where the typical weight storage
capacity of
6% is common, this would provide 480 grams of usable hydrogen. With a 50% fuel
cell system efficiency (typical) and where the specific energy of hydrogen
fuel is
33,410 Wh/kg (lower heating value; room temperature), the energy available
would
be 0.480 kg * 33,410 Wh/kg * 0.5 = 8018.4 Wh, more than five times that
available
from lithium ion batteries.
[00057] Alternatively, for the same energy available from lithium ion
batteries, the
soldier could carry a reduced mass of 1600 Wh / 8018.4 Wh * 8 kg = 1.6 kg of
hydrogen fuel storage.
[00058] Alternatively, if the soldier did not need to travel 120 km, no energy
storage mass would need to be carried at all and the residual energy from the
air
transportable fuel cell power system could be used on the ground. This is
especially
true if a fixed wing or hybrid VTOL fixed wing UAV configuration was
implemented.
[00059] The air transportable fuel cell power system could also be used in
emergency response situations or for disaster relief, providing an autonomous
power
source which could be sent to a pinpoint location via its autopilot and global
positioning system (GPS), thereby providing emergency power for communications
equipment, lighting, cell towers, etc.
[00060] Because the UAV functions via fuel cell, it could also provide some
amounts of heat and water to disaster victims, as byproducts of the fuel cell
reaction.
[00061] The air transportable fuel cell power system could be used to provide
emergency power to a disabled personal watercraft or sailing vessel located at
sea.
[00062] The hydrogen used as fuel for the air transportable fuel cell power
system
could be generated remotely onsite via chemical reaction (i.e. chemical or
metal
hydride), electrolysis via solar or other power source, solar using
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photoelectrochemical cells (PECs), etc. thereby increasing the available
energy from
the fuel cell system by orders of magnitude.
[00063] Other UAV platforms than multirotor could be used including fixed-wing
aircraft and hybrid fixed-wing/vertical takeoff and landing (VTOL) aircraft.
The later
platform would offer the greatest potential for the air transportable fuel
cell power
system since it could take off and land vertically, while flying with
increased
efficiency and reduced energy consumption during straight and level flight,
thereby
providing the potential for more energy available at the remote field
location.
[00064] The air transportable fuel cell power system could be configured to
carry a
very lightweight shelter or insulating material, which could be assembled at a
remote
location by a disaster victim, and connected to the fuel cell system to use
the
available power, heat and water which would increase the chances of survival
while
the victim is waiting for a conventional rescue method to arrive.
[00065] Thus, we have now developed a new and unobvious system in which a
fuel cell powered unmanned aerial vehicle can be reconfigured to provide an
air
transportable field power source of very high specific energy for operation in
remote
areas. An integrated field power system can interface with receptacles for one
or
more power sources, such as a hydrogen fuel cell, where the fuel is in
particular
hydrogen gas, liquid hydrogen, metal hydrides or chemical hydrides. The
specific
energy of the overall approach and therefore the available energy in the field
are
increased dramatically by the fact that the user must only transport hydrogen
fuel,
and not the actual power source. Our system can be applied to all applications
which require a lightweight source of energy in a remote field location.
Other Embodiments
[00066] From the foregoing description, it will be apparent to one of ordinary
skill in
the art that variations and modifications may be made to the embodiments
described
herein to adapt it to various usages and conditions.
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