WO2015073084A1

WO2015073084A1 - Hybrid co-axial shaft in shaft transmission using planetary gear set for multiple sources of torque

Info

Publication number: WO2015073084A1
Application number: PCT/US2014/051948
Authority: WO
Inventors: Jean Nicolas Koster; Gavin KUTIL; Arthur KREUTER; Tyler DRAKE; Corey PACKARD; Gauravdev S. SOIN
Original assignee: The Regents Of The University Of Colorado, A Body Corporate
Priority date: 2013-08-20
Filing date: 2014-08-20
Publication date: 2015-05-21

Abstract

A drive system for a vehicle includes two torque sources, such as engines/motors that are each coupled with the shaft of a power transfer device providing propulsion of the vehicle via a planetary gear system; wherein the drive shaft of the second torque source is hollow and the drive shaft of the first torque source extends within the first drive shaft coaxially to each other and the power transfer device; wherein both drive shafts connect with the planetary gear system; and wherein the first drive shaft and the second drive shaft can optionally interface via one-way bearings to provide a clutchless hybrid propulsion system and vehicle.

Description

Hybrid Co-Axial Shaft in Shaft Transmission Using Planetary Gear Set for Multiple Sources of Torque

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application is related to U.S. patent application no. 12/982,109 filed 30 December 2010 entitled "Hybrid transmission using planetary gear set for multiple sources of torque for aeronautical vehicles", U.S. patent application no. 12/982,130 filed 30 December 2010 entitled "Hybrid transmission using planetary gear set for multiple sources of torque for marine or two wheeled land vehicles," and 13/421 ,646 filed 15 March 2012 entitled "Hybrid transmission using planetary gear set for multiple sources of torque for aeronautical vehicles," each of which is hereby incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The technology described herein relates to a coaxial alignment of two power sources, such as electric motors, or hybrid architectures such as internal combustion and electric motor; or turbine and electric motor.

BACKGROUND

[0003] A vehicle (Latin: vehiculum) is a device that is designed or used to transport people, payloads, or cargo, (e.g. bicycles, cars, motorcycles, trains, ships, boats, and aircraft). Vehicles that do not travel on land often can be called craft, such as watercraft, sail craft, aircraft, hovercraft, and spacecraft. Land vehicles are classified broadly by what is used to apply steering and drive forces against the ground, e.g., wheeled, tracked, railed, or skied. Propulsion is achieved in different ways, e.g., by wheels, propellers, rotary wings, tracks, water or air jets, skies, turbofans, burning fuel under pressure, and the like, that provide torque from one or more power sources, such as gas, electric, or other motors, engines, or power sources. A vehicle can be used for propulsion of personnel or payloads on land, in water, or in air, or a combination thereof. All vehicles, with the exception of some space vehicles, experience significant frictional drag, typically mainly air, or water drag or rolling resistance. Friction also occurs in many braking systems, although some braking systems are regenerative which permits recovery of some of the energy from the vehicle's motion. The friction generated by the vehicle acting over the distance it travels can determine the energy needed to be expended. For a vehicle that is travelling at constant speed, from the definition of mechanical energy to move a given distance the energy needed is simply: E = Fxs, where E is the energy, F is the friction force, x is the multiplier, and s is the distance. This determines the minimum amount of energy the power source must provide and can determine the vehicle's range. Vehicles, such as airplanes, require significantly more power for takeoff and select landing periods than is required for cruising at level flight. Conventional design of propeller driven airplanes involves selecting an engine or motor that is powerful enough to meet the highest power requirements, even though most of the typical flight profile is conducted at cruising speeds requiring lower power at around 60% of take-off power. However, the efficiency, including fuel efficiency, of internal combustion engines is usually very sensitive to operating power and engine rotational speed, with efficiency falling as power output and engine speed deviate from the maximum efficiency region. Thus, during a typical flight, the aircraft internal combustion engine can be operated at an inefficient power output. While electric motors are able to operate at high levels of efficiency and almost constant torque over a broader range of power output and rotational speed (RPM), the energy density, the required low mass of batteries for acceptable operational travel range, and cost of currently available electrical storage systems make all- electric power systems for airplanes problematic.

[0004] A standard planetary gear system is comprised of a sun gear, planetary gears with a planetary carrier, and a ring gear, see Fig. 1 (a). In a typical hybrid transmission for, e.g., an aeronautical vehicle, a first engine/motor is connected to the sun gear, a second engine/motor is connected to the planet carrier; the ring gear combines and transmits power (torque) to the propeller. The motors can be of same kind, such as dual electric motors, dual internal combustion engines, or a combination of electric motor and internal combustion engine. An alternate architecture is a hybrid electric-turbine system, where the turbine replaces the internal combustion engine. The co-axial architecture provides significant reduction in cross-sectional area, which is desired especially for air vehicles to reduce drag during flight.

[0005] The information included in this Background section of the specification, including any references cited herein and any description or discussion thereof, is included for technical reference purposes only and is not to be regarded subject matter by which the scope of the invention as defined in the claims is to be bound; and additionally specifically does not constitute any description or admission of any teaching of the prior art.

SU MMARY

[0006] The invention(s) described herein is/are designed to provide a clutchless co-axial hybrid transmission and/or system (and/or gearbox) to improve various propulsion systems using a combination of at least two available torque or power sources, while having one or more desired characteristics, e.g., but not limited to, power, torque, acceleration, cruising, fuel efficiency, battery charging, endurance, power sizing, weight, capacity, efficiency, speed, mechanically and/or electrically added system requirements, design, fuel selection, functional design, structural design, lift to drag ratio, weight, and/or other desired characteristic or component. The term clutchless can include, but is not limited to, a propulsion system without a clutch, which can be a controllable mechanical device that engages and disengages the power transmission, such as driving shaft of an engine and/or motor to a drive shaft connected to, e.g., a propeller, wheel, thruster, and the like. The technology described herein is/are optionally designed to provide a clutchless, and specifically a co-axial hybrid transmission system (and/or gearbox) to improve various propulsion systems using a combination of at least two available torque or power sources, while having one or more desired characteristics, e.g., but not limited to, power, torque, acceleration, cruising, fuel efficiency, battery charging, endurance, power sizing, weight, capacity, efficiency, speed, mechanically and/or electrically added system requirements, design, fuel selection, functional design, structural design, lift to drag ratio, weight, and/or other desired characteristic or component. The technology disclosed herein optionally comprises one or more of a mechanically additive gear system, transmission or hybrid engine coupled with the mechanically additive gear system that uses planetary gearing without clutch to coaxially mix the power output of two or more separate motors to drive the propulsion of a vehicle or to provide power through a driveshaft, gearing, belt, or other mechanical power transmission. This clutchless design can optionally include power provided to the transmission using two or more torque or power sources, e.g., alternative energy, fuel or electrical torque or power sources. Hybrid is defined herein as a combination of two or more torque or power sources which can be the same or different functionality; such as, but not limited to, an electric motor and an internal combustion engine. Coaxial is defined herein to mean that the torque output of all engines is on similar or different axis as the power transfer device such as a propeller, fan, gear, gear system, wheel, or other driver. In one non-limiting version, a clutchless drive train for a first motor (e.g., a radio controlled internal combustion engine) is routed through the axial center of the second motor (e.g., an out runner type electric motor) which is directly attached to the planetary gear system, nesting the drive shafts of the two motors. The nesting causes the two drive shafts to act as structural support for each other. Directional control for the driveshaft is achieved through one-way bearings which also serve as the locking mechanisms of the planetary gear system when the motors are utilized either independently or concurrently.

[0007] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. A more extensive presentation of features, details, utilities, and advantages of the present invention as defined in the claims is provided in the following written description of various embodiments of the invention and illustrated in the accompanying drawings, but which are not limiting to the invention and can include any modifications, changes, additions, alternatives, substitutions, or less elements or components thereof as evident to those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is a through-axis view of a standard planetary gear system.

[0009] FIG. 2 is a side elevation view of a drive assembly for a propeller showing an optional gear down system for the ICE.

[0010] FIG. 3 is an isometric view of the propeller to gear assembly of the drive assembly of FIG. 2 showing a flexible adaptor to connect the second drive source.

[0011] FIG. 4 is an isometric, exploded view of the gearbox assembly for the drive assembly of FIG. 2.

[0012] FIG. 5 is an isometric, exploded view of the planetary gear assembly of the shaft-in- shaft design assembly of FIG. 2.

[0013] FIG. 6 is an isometric view of an assembly of the electric motor coupled with the gear assembly (Fig 5); also shown is the required special bearing design for the coaxial arrangement of the shaft-in-shaft design through the electric motor.

[0014] FIG. 7 is an isometric view of the assembly of FIGs. 5 and 6 secured on several mounts.

[0015] FIG. 8 shows the power flow of the hyprid design with one ICE and one EM, including optional charging (photovoltaic, fuel cells, other) of batteries.

[0017] FIG. 9 sketches the main mechanical, electrical, and software systems required to operate the hybrid power system

DETAILED DESCRIPTION

[0018] At least one invention or development described herein is designed to provide various or alternative clutchless hybrid transmission systems, as well as propulsion systems and vehicles comprising such transmission systems, to improve various propulsion systems using a combination of at least two torque or power sources with the option for simultaneous or alternating power input from two or more torque or power sources, while providing desired characteristics or components. Such characteristics or component can include, but are not limited to: power, torque, acceleration, cruising speed or power, fuel efficiency, battery charging, endurance, power sizing, weight, capacity, efficiency, speed, mechanically and/or electrically added system requirements, design, fuel selection, functional design, structural design, lift to drag ratio, weight, and/or other desired characteristic or component.

[0019] A type of "clutchless co-axial hybrid transmission system" (optionally including at least one gearbox) can include the use of a, one or more, or at least one planetary or epicyclic gearing system or gearbox that allows power coupling between at least two sources of power and the drivetrain, power transfer device, or propulsion drive shaft of a propulsion system. One or more of the torque or power sources can be linked to any component of the planetary gearing system, such as but not limited to a sun, one or more planets, a ring, and/or a carrier or arm.

The planetary gear system can be one or more of a standard planetary gear system or a multi- ratio planetary gear system. Considerations for providing in selecting a planetary gear system can include, but are not limited to, one or more of efficiency, gear ratio, torque, PM

requirements, simultaneous input, weight, cost, manufacturing complexity or difficulty, power, acceleration, cruising, fuel efficiency, battery charging, endurance, power sizing, weight, capacity, efficiency, speed, mechanically and/or electrically added system requirements, design, fuel selection, functional design, structural design, lift to drag ratio, and the like. Alternative forms of a "clutchless co-axial hybrid transmission system" are provided that include or comprise, but are not limited to, at least one planetary or epicyclic gearing system that provides alternating power coupling between at least two sources of power and at least one propulsion drive shaft, and/or power transfer device. The power input, torque source, and/or propulsion drive shaft can be operably linked to one or more of a, one or more, or at least one of, a sun gear, a planetary gears, a ring gear, or a carrier or arm connected thereto, of planetary or epicyclic gearing system.

[0020] FIG. 1 depicts a typical planetary gear system with a sun gear, three planet gears, a planet carrier, and a ring gear. A planetary gear system can transfer torque to the propeller of a vehicle from at least two separate torque sources. The planetary gear system transfers torque through at least three channels: the sun gear, the planet carrier, and the ring gear. The typical planetary gear system allows for two torque inputs and one output. In one non- limiting embodiment, the two torque inputs may be through the sun gear and the planet carrier. The output torque may then be transferred by the ring gear and ring carrier to a shaft that drives a propeller or other motive mechanism.

[0021] FIG. 2 depicts a schematic side view of a propeller drive system with an electric motor ("EM") and an internal combustion engine ("ICE") that drives a planetary gear system of a type similar to that in FIG. 1. The internal combustion engine output shaft is co-axial with the sun gear shaft. The model in FIG. 2 shows an embodiment of the system with all of the components in their respective positions. Location is subject to vehicle system design. The schematic shows how all of the components are in-line with the propeller shaft. The layout of the internal combustion engine and electric motor shafts constitutes in-line in the hybrid propulsion system , which may be desirable in aircraft applications because slimmer or narrower engines allow for improved aerodynamic performance because of reduced cross sectional area drag. The design of the in-line system, allows for the drive shaft of the internal combustion engine to pass through the center of the electric motor.

[0022] The ICE may be replaced by another EM for a dual EM operation. Other torque input sources may also be considered, such as, but not limited to, a turbine; flywheel; compressed air or hydrogen powered engine; others providing power input. The ICE may be geared down to adjust the rotational shaft speed to the needs of the planetary gear design. This allows for a broader choice of ICE engines, including turbines, that may operate at higher RPM. [0023] A distinguishing feature of the present design of a drive system for a propeller- driven vehicle is its shaft-in-shaft configuration that allows two sources of torque (e.g., engines and /or motors)— exemplified as an internal combustion engine, which is the source of a first torque, and an electric motor, which is the source of a second torque— to be on the same axis as a planetary gear system (see FIG. 2) and output, e.g., a propeller as shown explicitly in FIG. 3. The source of the first torque (e.g., the internal combustion engine) connects to the sun gear via an inner shaft, and the source of the second torque (e.g., the electric motor) connects the planet carrier via an outer hollow shaft. As used herein, the term "motor" may be used generally to refer to a torque or power source, which may be in the form of any type of motor, engine, or other drive system.

[0024] Several specifically placed one-way bearings allow for independent and collaborative torque addition to the output shaft (propeller, fan). In case one torque source is at zero torque, these bearings avoid retro-rotation that would reduce the rotation speed and power transmission at the output shaft. The full power (minus efficiency losses) of the one and only operating torque source will be transferred to the output device. This allows for a smooth transition from a two torque or power source operation to single torque or power source operation without the need for mechanical clutches.

[0025] With the dual engine/motor hybrid system, should one engine/motor fail during operation/flight, the second engine/motor can seamlessly take over propulsion and thereby increase safety by providing safe landing opportunities.

[0026] FIG. 2 shows a schematic representation of a planetary gear system for a hybrid drive assembly for a propeller driven vehicle. Here the top level functionality is explained. The propeller, 101 , is positioned at the left. A shaft 102 for a ring carrier 104 is held within a support structure 103, which is attached to a baseplate 1 13 and coupled to a ring gear 201 via the ring carrier 104. The planetary gear system includes a ring gear 201 , a sun gear 202, and planet gears 203. An electric motor EM is attached to a fixture on the base plate 1 13. The rotating outer shell of the electric motor EM (e.g., an out runner-type motor) is coupled to the planet carrier 106. The stator of the electric motor EM is mounted to a fixture 1 17, which is attached to the baseplate. An internal combustion engine ICE is also attached via mounts 1 12 to the baseplate 1 13. The shaft 204 of the internal combustion engine ICE can be down geared (FIG. 2) to or flex-coupled (FIG. 2, 6, 7) with a shaft 108 that drives the sun gear 202 after passing axially through the electric motor EM, which provides a second torque source, with unobstructed rotation capability. The alignment quality of the internal combustion engine ICE-driven shaft, 108, through the electric motor EM is important. The hollow shaft 107 provides a bearing support 308 to the internal shaft 108.

[0027] A similar, but somewhat modified, design may include switching the position of the electric motor EM in line behind (up-shaft) the internal combustion engine ICE. The internal combustion engine ICE must satisfy the need for axial pass through without rotational obstruction from the shaft of the electric motor EM. Different kinds of electric motors can be used in such an architecture and are not limited to out runner-type motors.

[0028] The ICE may be replaced by another EM for a dual lk,/1 operation. Other torque input sources may also be considered, such as a turbine; flywheel; compressed air or hydrogen powered engine; others providing mechanical power input.

[0029] FIG. 3 shows the exploded view of the assembly of a propeller/fan 101 of any kind coupled to the ring gear carrier 1 04. The ring gear carrier 104 may be connected to the ring gear 201 . The propeller 101 is attached to the propeller shaft 1 02, which passes through a support cylinder 1 03 to connect to the ring carrier 104. A forward propeller shaft bearing 301 and an aft propeller shaft bearing 302 are integrated at the support structure 103 to provide axial stability of the propeller-gear system . A thrust bearing 303 absorbs axial loads between the static support structure 103 and the rotating shaft assembly 101 , 102, 104.

[0030] FIG. 4 depicts the details of the gearbox assembly. The ring carrier 104, connecting to the propeller output is attached to the ring gear 201 . The planet gears, 203, are attached to the planet carrier 106 via shafts 105. Note that the gear ratio in the figures is merely exemplary and is not intended suggest a particular or required gear ratio for use in the device. The planet gears 203 engage internally with the ring carrier 201. The planet gears 203 are held in their specific location in the ring carrier 106 with one front and one aft bearing 305 to assure stability. The planet carrier 106 may be driven by the electric motor EM according to FIG. 2.

[0031] The sun gear, 202, is attached to a shaft, 108 (not shown for clarity), and is in contact to a thrust bearing, 304, to hold axial loads on that shaft, 108, which is connected to the ICE as shown in Figure 3.

[0032] FI G. 5 shows the electric motor EM sub-assembly that is attached to the planetary gear carrier 106 of FIG. 4. A hollow tube adapter 107 is attached on a front side to the planetary gear carrier 106 and aft to an outer rotating shell of the electric motor EM. The electric motor EM is an outrunner-type (i.e., the rotor is the outer shell of the electric motor EM), which allows the electric motor EM to be positioned between the planetary gear carrier 106 and the internal combustion engine ICE. The hollow shaft 107 is the nexus of the shaft-in-shaft design as it allows the smaller diameter shaft 1 08 (see FI G. 3) to pass through the electric motor EM to connect with the sun gear 202. A radial support bearing 308 may be placed inside the adapter 107 to carry the shaft 108, which is coupled to the internal com bustion engine I CE . This allows the shaft 108 and adaptor 1 07 to rotate independently of one another. A shaft adapter washer 1 14 allows the shaft adapter 107 to be attached to the shroud of the electric motor EM using a radial set screw and an interference fit between the shaft adapter 107 and the washer 1 14. A one-way bearing 307 is fixed onto the shaft 107 and is held in place by a fixture 1 10 (Fig.3) to limit shaft rotation to one direction only. Thrust bearings 306 placed on both sides of the one way bearing absorb axial forces.

[0033] FIG. 6 depicts the shaft-in-shaft planetary gear system without mounts and without the propeller and internal combustion engine. FIG. 7 depicts the full assembly of the shaft-in-shaft hybrid propulsion system mounted on a baseplate with internal combustion engine ICE placed aft.

[0034] Two notable technologies enable the shaft-in-shaft design : a modified electric motor and one-way bearings. In a design where the electric motor is situated between gear system and an internal combustion engine, the electric motor may be an "out-runner" type (i.e., the rotor is the outer shell and the stator is the inner magnet winding). Available commercial out runner motors used in testing the designs disclosed herein operate outside their design spectrum and thus require some mechanical modifications along the internal axis to allow for the throughput of the shaft connected to the internal combustion engine with impact on efficiency limited to bearings.

[0035] In a design in which the internal combustion engine is placed between the gears and the electric motor, the internal combustion engine must be capable of accepting

modifications for a shaft throughput from the electric motor shaft side. In such a design conventional electric motors can be utilized; with an axial central rotor and a static outer casing.

[0036] A consumer, off-the-shelf, out runner-type, electric motor comes with a fixed inner shaft which connects to its outer shell/can rotor at the rear of the electric motor. In this exemplary design , the original, axial, static shaft was removed and modified to allow for shaft throughput. The adapter 107, which is a hollow cylindrical piece custom built to fit the motor was placed outside at the end of the electric motor where the electric motor's original inner shaft was connected from the inside to the output.

[0037] In an exemplary embodiment, the custom adapter 107 (FIG. 5) was mounted on the outside of the electric motor using set screws. Any problems of slippage at this connection point are best avoided. Another solution is to redesign the electric motors to accommodate these new requirements of shaft-in-shaft technology. Then, the internal combustion engine shaft coming from the internal combustion engine coupling replaces the inner original shaft of the electric motor, allowing for the shaft-in-shaft design concept.

[0038] Another technology that enables the dual torque design is the use of one-way bearings. One way bearings allow for both input torque sources to operate individually and avoid retro-rotation of shafts. Retro-rotation takes away power that should be transferred to the output shaft, which may not be useful, e.g., but not limited to, unless purposed to generate energy with an alternator. [0039] An issue with earlier designs was "torque feedback." In earlier designs when the two motors were not operating in concert and only operated independently, the electric motor imposed a reaction torque on the combustion engine, causing the combustion shaft to rotate in the opposite direction. This reduced the power that the electric motor output to the gearbox. Also, when the engine and motor were run in tandem; that same torque caused the combustion engine to stall so the engines were unable to reach optimum power output in neither operational case. One-way bearings are installed along the inner and outer shafts to ensure that they turn in one predetermined direction, abrogating the torque feedback issue found in prior designs.

[0040] The hybrid design is a mechanically additive system (MAS) design that mates two sources of torque, such as an internal combustion engine and electric motor components. Alternatively, two internal combustion engines or two electric motors can be integrated in the architecture as well. The architecture is also appropriate for a hybrid turbine-electric motor system or a geared turbo-prop engine, where the electric motor contributes to drive the fan. Through this architecture, a planetary (or cyclic) gearing system allows for collaborative and additive internal combustion engine and electric motor operations. Torque can be applied to the output (e.g., propeller) by operating the first torque source (e.g., an internal combustion engine) and the second torque source (e.g., an electric motor) individually or cooperatively. There are no clutches in this system. The system is not impacted by input rpm or power that comes off the two torque sources or whether one of the torque sources is off line.

[0041] FIG. 8 qualitatively diagrams the energy flow through the MAS layout. The essence of the MAS subsystem is the planetary gearing system. Both the internal combustion engine and electric motor mechanically run the gearbox which allows for a single propeller output shaft to be additively driven. The electric motor may be powered by a battery array or any other electric torque or power source. The overall efficiency of this subsystem configuration may be about 85%.

[0042] A top-level layout of the hybrid propulsion system design showing major components and major connections throughout the system is shown in Figure 9. Each component uses a physical, data, or electrical connection to other components in order to successfully operate the hybrid propulsion system: In FIG. 9 each type of interface is shown in a different line presentation (i.e., solid, dashed, or dotted). The gearbox adds power from the internal combustion engine and the electric motor. The gearbox possesses two inputs— one for the first torque source (e.g., an internal combustion engine) and another for the second torque source (e.g., an electric motor)— which allows the vehicle to operate in the different modes defined by the concept of operations (e.g., as presented herein). There is only one output, which connects to the aircraft propeller (or other device, such as a fan, wheel, ship propeller, etc.). The control system is capable of switching between the two different throttling mechanisms from the ground. Transmitter and receiver references indicate the prospect of (remote) pilot control. Those can be replaced by autopilot systems.

[0043] Options of operation using the system may include one or more of, e.g., but not limited to, power, torque, acceleration, cruising, fuel efficiency, battery charging, endurance, power sizing, weight, capacity, efficiency, speed, mechanically and/or electrically added system requirements, design, fuel selection, functional design, structural design, lift to drag ratio, weight, and/or other desired characteristic or component; and/or one of the following, as non-limiting examples, e.g., for an aeronautical vehicle:

1 ) Full power needed, e.g., during take-off. Both sources of torque (e.g., electric motor and internal combustion engine) power are combined/added for high power output at the propeller, fan, wheel, etc.

2) Cruise flight. As about 60% power is needed during cruise phase, the flight can theoretically be powered by the electric motor only or by the internal combustion engine (ICE) only when power specifications of engines and motors are sized appropriately, with appropriate energy and fuel resources. The ICE can be operated at highest fuel efficiency conditions.

Electric flight allows for quiet flight and internal combustion flight provides endurance for long distances, given the high energy density of fuels. Quiet electric take-off-and-landing can be realized with the electric motor only, which reduces noise level near airports.

3) Considering that diesel engines are sensitive to stall in very cold air when throttling, operation of aircraft with diesel engines hybridized with electric motors may be appealing. The diesel engine may be operated at constant rpm at all times during takeoff and cruise. Transient needs may then be met exclusively by the electric motor.

Advantages of the Technology:

[0044] The shaft-in-shaft design gives better structural support through higher rigidity than an individual shaft and through consolidation of support mounts. The two shafts support each other structurally and give improved axial vibration characteristics than the shafts would have on their own. This allows the two shafts to be sized individually for torque considerations allowing each shaft to weigh less. If this was done in traditional arrangements then the shafts can have issues with axial vibrations.

[0045] The other structural advantage to the shaft-in-shaft design is the ability to consolidate mounts. The same mount can be used to support both of the shafts at the same time for virtually the same mass as it would take to support a single shaft. The mount for the shafts also supports the gearbox as well as the out runner shell of the electric motor and the mount for the electric motor supports the internal combustion engine driveshaft and the internal combustion engine gearing as well. [0046] The shaft-in-shaft design gives better aerodynamic characteristics than alternative (off-axis) designs. If the shafts were to run parallel to each other it would require extra gearing, support mounts, and possibly torque or power sources (i.e., the electric motor or internal combustion engine) to be offset from the propeller axis. This would result in a larger cross-sectional profile area relative to the airflow which would correspond to higher aerodynamic/fluid drag on the system. The shaft-in-shaft design lets the profile area be roughly equal to the largest component in the drivetrain. In the exemplary system, the largest components would be the ring gear and elements of the internal combustion engine.

[0047] In one embodiment of a clutchless hybrid transmission system, the electric motor may be an "out runner" type of motor requiring special mechanical modifications to pass the shaft from the second motor axially without contact. The rotor with wiring of this out runner type motor remains stationary during operation while the outer motor-magnet sub shell/can system (out runner "stator") rotates. The moving outer structure is connected with a hollow shaft to planet carrier and transmits rotation energy (torque) to the planet carrier. The use of a conventional electric motor with rotating axial shaft is possible through appropriate redesign of the system (i.e., appropriate placement of the internal combustion engine and the electric motor) allowing for a hollow shaft operation.

[0048] Sources of torque can be multiple:

Source #1 and #2 can be both of same kind such as electric motors, combustion engines, turbines, compressed air, other sources of powered torque.

[0049] Source #1 and #2 can be different kinds of motors:

Source #1 can be any internal combustion engine type, gas, (bio-)diesel, piston, rotary, or other using such fuels. Depending on position within assembly, they must be adapted for shaft-in- shaft operation.

Source #2 can be any kind of electric motor (electric motor) adapted to the shaft-in-shaft architecture with some mechanical modifications; and

Source #1 and #2 may be in reversible order location depending upon design.

Source #1 and #2 may be of same kind: dual electric motor, or dual internal combustion engine.

[0050] In one embodiment, wherein the first torque or power source is the internal combustion engine and the second torque or power source is the electric motor, the hybrid propulsion system preserves high efficiency of torque generated by the internal combustion engine. In operation, e.g., at higher power or torque conditions, e.g., for aeronautical vehicles, at take-off, both the internal combustion engine and the electric motor simultaneously contribute torque in the hybrid propulsion system, resulting in maximum torque and/or rotation of the propeller (i.e. thrust) via the ring gear and the propeller shaft. As the aircraft approaches cruising speed, the power output of the electric motor is gradually reduced. At cruising speed, the electric motor may be switched off completely, whereby the torsional resistance of the unpowered electric motor is sufficient to channel all of the rotational power from the internal combustion engine to the propeller shaft. When additional power is needed, by way of example, in carrying out low speed landing maneuvers, the electric motor can be used to augment total power to the propeller shaft. A clutchless co-axial hybrid propulsion system is advantageous because it allows the use of a light weight first torque or power source, e.g. the internal combustion engine, with addition of the second torque or power source, e.g. the electrical motor, to lower the total weight of an aircraft's propulsion system. The embodiments of Figs. 2 and 3 allows torque or power source selection that lowers the weight of the internal combustion engine substantially, which is not offset by the addition of an electric motor plus the planetary gear system. It will be apparent to one of ordinary skill in the art from this disclosure that the electrical energy storage system should be carefully selected to preserve the weight advantage. Similar other vehicles can be used in similar manners.

[0051] Other modes of operation include shutting off the internal combustion engine in flight and allowing the propeller to act as both a source of drag and a wind generator. This can be useful for highly streamlined aircraft during approach and landing maneuvers. Rather than using flaps that merely dissipate energy, the appropriate propeller can recapture a portion of this energy as the torque is transferred to the electric motor, which in the "off" setting may function as an alternator, generator, dynamo, or the like. The recaptured energy may then recharge batteries or other electrical energy storage systems. The hybrid propulsion system also facilitates the use of the propeller as a starter for the internal combustion engine in flight. This may be accomplished by applying low power to the electric motor in the reverse setting sufficient to make the torsional resistance of the electric motor shaft greater than that of the internal combustion engine. The power from the propeller, being turned by the air as the aircraft glides, is transferred to the internal combustion engine shaft, serving as a starter.

[0052] With addition of a braking mechanism on the propeller shaft, the electric motor can be used directly as a starter motor for the internal combustion engine. When the propeller shaft brake is engaged, all of the torsional energy is transferred via the planetary gear system to the internal combustion engine. This could be used on the ground or in-flight, though care must be used in flight, as the sudden increase in drag could alter aircraft performance.

[0053] The electric motor may also be designed to continuously provide a portion of thrust during cruise, which would allow for additional weight reduction due to a yet smaller internal combustion engine. However, to preserve the operating range of the aircraft, increased battery capacity would be required. Because the demands on the first torque or power source of torque are considerably less than that of a single torque or power source, various engines may be considered. For instance, diesel engines and small turbine systems could be used, thereby providing advantages of higher energy density of fuel, lower maintenance requirements, and reduced pollution. It is also possible to use two internal combustion engines for the first and second torque or power sources and no electric motor, which would still provide operational efficiency advantages. In another embodiment, more than two torque or power sources of torque are utilized by using additional planetary gear systems in serial arrangement.

[0054] A clutchless co-axial hybrid transmission system vehicle can include where the propulsion drive shaft driving the propulsion of the vehicle is via one or more of at least one transmission, at least one differential, or at least one other gearing device that operates at angles from 0 to 180 degrees, e.g., but not limited to 0-90, 0-45, 0-25, 0-20, 0-15, 10-45, 10-60, 10-75, 25-45, 25-60, 25-90, and/or any range value therein, and/or including parallel, co-axial, and the like.

[0055] A clutchless co-axial hybrid transmission system vehicle can include where the propulsion is via at least one propulsion mechanism selected from an aeronautical propeller, a marine propeller, a wheel, or is via a friction or turbulence generating device.

[0056] One optional form of propulsion for unmanned and manned aeronautical, marine or amphibious vehicles that can be included for use with a clutchless c-axial hybrid transmission system include the use of a propeller or airscrew operably linked to a propulsion drive shaft. A propeller or airscrew comprises a set of small, wing-like aero foils set around a central hub which spins on an axis aligned in the direction of travel. Spinning the propeller creates aerodynamic lift, or thrust, in a forward direction. A tractor design mounts the propeller in front of the torque or power source, while a pusher design mounts it behind. Although the pusher design allows cleaner airflow over the wing, tractor configuration is more common because it allows cleaner airflow to the propeller and provides a better weight distribution. A contra-prop arrangement has a second propeller close behind the first one on the same axis, which rotates in the opposite direction. A variation on the propeller is to use many broad blades to create a fan. Such fans are traditionally surrounded by a ring-shaped fairing or duct, as ducted fans. Any suitable propeller of airscrew can be used with a clutchless c-axial hybrid transmission system , as disclosed herein or as known in the art.

[0057] A well-designed propeller typically has an efficiency of around 80% when operating in the best regime. Changes to a propeller's efficiency are produced by a number of factors, notably adjustments to the helix angle(9), the angle between the resultant relative velocity and the blade rotation direction, and to blade pitch (where θ = Φ + a) . Very small pitch and helix angles give a good performance against resistance but provide little thrust, while larger angles have the opposite effect. The best helix angle is when the blade is acting as a wing producing much more lift than drag.

[0058] A propeller's efficiency is determined by propulsive power out thrust.^■ axial speed

η =

shaft power in resistance torque - rotational speed

Propellers are similar in aero foil section to a low drag wing and as such are poor in operation when at other than their optimum angle of attack. Control systems are required to counter the need for accurate matching of pitch to flight speed and engine speed. Further consideration is the number and the shape of the blades used. Increasing the aspect ratio of the blades reduces drag but the amount of thrust produced depends on blade area, so using high aspect blades can lead to the need for a propeller diameter which is unusable. A further balance is that using a smaller number of blades reduces interference effects between the blades, but to have sufficient blade area to transmit the available power within a set diameter means a compromise is needed. Increasing the number of blades also decreases the amount of work each blade is required to perform, limiting the local Mach number - a significant performance limit on propellers. Federal Aviation Administration, Airframe & Powerplant Mechanics Powerplant Handbook U.S Department of Transportation, Jeppesen Sanderson, 1976, the contents of which are entirely incorporated herein by reference.

[0059] A clutchless hybrid transmission can comprise one or more planetary or epicyclic gear systems. A gear is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque. Two or more gears working in tandem are called a transmission and can produce a mechanical advantage through a gear ratio and thus may be considered a simple machine. Geared devices can change the speed, magnitude, and direction of a torque or power source. The most common situation is for a gear to mesh with another gear, however a gear can also mesh a non-rotating toothed part, called a rack, thereby producing translation instead of rotation. The gears in a transmission are analogous to the wheels in a pulley. An advantage of gears is that the teeth of a gear prevent slipping. When two gears of unequal number of teeth are combined a mechanical advantage is produced, with both the rotational speeds and the torques of the two gears differing in a simple relationship.

[0060] In transmissions which offer multiple gear ratios, the term gear, as in first gear, refers to a gear ratio rather than an actual physical gear. The term is used to describe similar devices even when gear ratio is continuous rather than discrete, or when the device does not actually contain any gears, as in a continuously variable transmission. The gear ratio in an epicyclic or planetary gearing system is somewhat non-intuitive, particularly because there are several ways in which an input rotation can be converted into an output rotation. The three basic components of the epicyclic or planetary gear or carrier are: Sun: The central gear; Planet carrier: Holds one or more peripheral planet gears, of the same size, meshed with the sun gear; Ring (or ring): An outer ring with inward-facing teeth that mesh with the planet gear or gears. In many epicyclic gearing systems, one of these three basic components is held stationary; one or more of the remaining components is an input, providing power to the system, while the last component is an output, receiving power from the system. The ratio of input rotation to output rotation is dependent upon the number of teeth in each gear, and upon which component is held stationary. In hybrid vehicle transmissions, two of the components are used as inputs with the third providing output relative to the two inputs.

[0061] One situation is when the planetary carrier is held stationary, and the sun gear is used as input. In this case, the planetary gears simply rotate about their own axes at a rate determined by the number of teeth in each gear. If the sun gear has S teeth, and each planet gear has P teeth, then the ratio is equal to -S/P. For instance, if the sun gear has 24 teeth, and each planet has 16 teeth, then the ratio is -24/16, or -3/2; this means that one clockwise turn of the sun gear produces 1.5 counterclockwise turns of the planet gears. This rotation of the planet gears can in turn drive the ring, in a corresponding ratio. If the ring has A teeth, then the ring will rotate by P/A turns for each turn of the planet gears. For instance, if the ring has 64 teeth, and the planets 16, one clockwise turn of a planet gear results in 16/64, or 1/4 clockwise turns of the ring.

Extending this case from the one above: One turn of the sun gear results in - S / P turns of the planets; One turn of a planet gear results in P / A turns of the ring; So, with the planetary carrier locked, one turn of the sun gear results in - S / A turns of the ring.

[0062] The ring can also be held fixed, with input provided to the planetary gear carrier; output rotation is then produced from the sun gear. This configuration can produce an increase in gear ratio, equal to 1 +A/S. These can be described by the equation: (2 + n)wa + n os - 2(1 + η)ωο = 0, where n is the form factor of the planetary gear, defined by: If the ring is held stationary and the sun gear is used as the input, the planet carrier will be the output. The gear ratio in this case will be 1/(1 +A S). This is the lowest gear ratio attainable with an epicyclic gear train. This type of gearing is sometimes used in tractors and construction equipment to provide high torque to the drive wheels.

[0063] Gear Materials: Any suitable material can be used for gears in a clutchless co-axial hybrid transmission or system. Non-limiting examples include numerous metals, nonferrous alloys, cast irons, powder-metallurgy and plastics can used in the manufacture of gears.

However steels are most commonly used because of their high strength to weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A properly designed plastic gear can replace steel in many cases because it has many desirable properties, including, but not limited to, dirt tolerance, low speed meshing, and the ability to "skip" quite well. Gears are most commonly produced via hobbing, but they are also shaped, broached, cast, and in the case of plastic gears, including but not limited to, injection molded. For metal gears the teeth are usually heat treated to make them hard and more wear resistant while leaving the core soft and tough. For large gears that are prone to warp a quench press is used. A transmission or gearbox provides speed and torque conversions from a rotating torque or power source to another device using gear ratios. In British English the term transmission refers to the whole drive train, including gearbox, clutch, prop shaft (for rear-wheel drive), differential and final drive shafts. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and anywhere else rotational speed and torque needs to be adapted. Often, a transmission will have multiple gear ratios (or simply "gears"), with the ability to switch between them as speed varies. This switching may be done manually (by the operator), or automatically. Directional (forward and reverse) control may also be provided. Single-ratio transmissions also exist, which simply change the speed and torque (and sometimes direction) of motor output. In motor vehicle applications, the transmission will generally be connected to the propulsion shaft of the engine. The output of the transmission is transmitted via driveshaft to one or more differentials, which in turn drive the wheels, propeller, or other propulsion device. While a differential may also provide gear reduction, its primary purpose is to change the direction of rotation.

[0064] A clutchless hybrid transmission system can optionally comprise at least one sun gear, at least one planetary gear, and at least one ring gear. One or more sun gears and/or ring gears can be directly linked to at least one planetary gear. Each sun gear can be linked to each set of planetary gears. Each sun gear can be linked via each set of planetary gears to a ring gear. A set of planetary gears can be in the same plane as the linked sun gear and/or ring gear. The planetary gear set can comprise 2, 3, 4, 5, 6, 7, or 8 planetary gears in the same or different plane. One or set of planetary gears can be operably linked to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft. A ring gear can be operably linked to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft. A sun gear can be operably linked to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft.

[0065] A set of planetary gears can be linked via at least one carrier or arm to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft. A ring gear can be linked via at least one carrier or arm to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft. A sun gear can be linked via at least one carrier or arm to at least one drive shaft, such as at least one propulsion drive shaft or at least one power driveshaft.

[0066] A clutchless hybrid transmission system can optionally comprise at least one carrier or arm operably connected to at least one of the at least one sun gear, at least one planetary gear, and at least one ring gear. A clutchless hybrid transmission system can optionally comprise wherein at least one of the at least one propulsion drive shaft is connected to one of the at least one sun gear, at least one planetary gear, and at least one ring gear. A clutchless hybrid transmission system can optionally comprise wherein the connection is via the at least one carrier or arm. A clutchless hybrid transmission system can optionally comprise wherein the propulsion drive shaft is connected to the ring gear via the carrier or arm and the at least two sources of power are connected via dual power drive shafts that are separate or concentric and each drive a different of the planetary gear and the sun gear that drive the propulsion drive shaft of the propulsion system. A clutchless hybrid transmission system can optionally further include, wherein the ratio of the at least one planetary gear and the at least one sun gear is between about 0.2 and about 0.8, e.g., but not limited to, .2, .3, .4., .5, .6., .7., .8, .9, or any range or value therein, e.g., + or - .01 , .02., .03, .04. ,.05., .06, .07, .08, .09, .001 , .002, .003, .004, .005., .006, .007, .008, .009, .0001 , such as but not limited to .4-.6, .3-.8, .41-.59, .45-.55, .47-.53, .49-.51 , or any range or value therein.

[0067] A clutchless hybrid transmission system can optionally further include, wherein the ratio of the at least one planetary gear and the at least one sun gear is about 0.5. A clutchless hybrid transmission system can optionally further include, wherein the at least one planetary or epicyclic gearing system provides simultaneous power coupling between at least two sources of power and at least one propulsion drive shaft of the hybrid propulsion system. A clutchless hybrid transmission system can optionally further include, at least one battery or electrical storing system that powers the EM. A clutchless hybrid transmission system can optionally further include, wherein the ICE charges the battery or electrical storing system. A clutchless hybrid transmission system can optionally further include, wherein the ICE and EM power the drive shaft simultaneously as a mechanically additive system. A method is also provided for transferring power from at least two torque or power sources to at least one propulsion drive shaft in a vehicle, comprising (a) providing a hybrid propulsion system comprising at least one clutchless hybrid transmission system comprising at least one planetary or epicyclic gearing system that provides alternating or simultaneous power coupling between the at least two sources of power and the at least one propulsion drive shaft of the hybrid propulsion system.

[0068] PLANETARY GEARS: A planetary gearbox that can optionally be used in a clutchless hybrid transmission can comprise three stages of gears, any of which can either be an input or an output. One planetary gear option is the multi ratio planetary gear in which the planet gears have multiple ratios allowing for either an additional gear ratio within the box or an addition input/output. The other planetary gearing system is the standard planetary gear in which the planets consist of only one gear size . A planetary gearing system (also known as an epicyclic) is composed of three sets of gears; a large internal gear surrounding the others, a single standard spur gear in the center, and typically two to four spur gears spanning the space between the other two. The standard naming technique for the system is planetary in nature. The internal gear is labeled the ring gear, the center gear is labeled the sun gear and the gears spanning the space are labeled planet gears. The planet gears are held together with a structure labeled carrier (or arm); and can include carrier or arms associated with one or more of the planetary gear components, e.g., one or more, of the sun planet, or ring gears, and optionally wherein the arm or carrier components can be attached to, or transfer torque, or power between two or more of the first or second propulsion drive shaft, one or more bearings (e.g., one way bearings), and/or power transfer devices.

[0069] A first governing equation for the planetary system is the RPM relation.

^ _ N_{5un ^} ⁽^carrier ~ ^ring

Nring ^sun ~ ^carrier

Where R is the gear ratio, N is the number of teeth, and ω is the angular velocity.

[0070] The equation can be rearranged into another useful form:

N_sun ^■ ti⁾ _sun + N_ri_ng ^■ 0 _ri_ng = (N ing N_Sun) ' ^carrier

→^{R '} <¾un + ^ωπη_β = (1 + R) - ^arm

[0071] A gear ratio can be further defined. Since the planet and sun gears must fit into the ring gear a simple summation is produced.

Nsun ^^planet ~ N_ring

[0072] A useful second governing equation for the planetary system is the torque equation which is derived from the power equation.

Pout ⁼ iPinl + Pinl) ^'

P = τ^■ ω

Where is P the power, η is the efficiency of the gearbox, τ is the torque, and ω is the angular velocity. This equation is used to find the power and output (the propeller).

[0073] Alternative, known equivalent can be used, as known in the art. Since the planetary system allows for at least three components, the system can be designed one or more of desired power, torque, or desired efficiency. Each component can be attached to any of the mechanical systems (example: ring can be attached to the propeller, EM or ICE). Also since the gear ratio can be set the system is very dynamic. A gear ratio can be selected depending on the desired characteristics of the propulsion system, where each component, such as propulsion drive shaft, power supply 1 and power supply 2, can be attached each to one of a ring gear, a ring gear carrier, a sun gear, a sun gear carrier, a planet carrier or arm, or a planet gear.

[0074] Torque or power sources. Alternative "hybrid propulsion systems" are also provided that can comprise at least one clutchless hybrid transmission system and at least two sources of power operably linked to a propulsion drive shaft. Non-limiting examples of the at least two sources of power can comprise at least one of any type of internal combustion engine (ICE) and any type of at least one electric motor (EM). Such sources of power can also or alternatively include any other form of suitable torque or power source, e.g., but not limited to, fuel cells, solar power (e.g., photovoltaic and the like), steam engines, and the like. [0075] An internal combustion engine is an engine in which the combustion of a fuel (which can be, but is not limited to, a fossil fuel or hydrocarbon) occurs with an oxidizer (usually air or other combustible/gas or gas mixture) in a combustion chamber. In an internal combustion engine the expansion of the high-temperature and -pressure gases produced by combustion applies direct force to some component of the engine, such as pistons, turbine blades, or a nozzle. This force moves the component over a distance, generating useful mechanical energy.

[0076] The term internal combustion engine can include, but is not limited to, an engine in which combustion is intermittent or semi continuous, such as four-stroke, two-stroke, five stroke, or six stroke, piston engines, along with any known variants, such as, but not limited to, a Wankel rotary engine or other known type of engine. A second class of internal combustion engines use continuous combustion, e.g., but not limited to, gas turbines, jet engines and most rocket engines, each of which are internal combustion engines on the same principle as previously described.

[0077] The internal combustion engine (or ICE) is different from external combustion engines (or ECE), such as steam or Stirling engines, in which the energy is delivered to a working fluid not consisting of, mixed with, or contaminated by combustion products. Working fluids can include, but are not limited to, air, a gas, water, pressurized water, or any suitable liquid, heated in some kind of boiler or other suitable device.

[0078] A large number of different designs for ICEs have been developed and built, with a variety of different characteristics, strengths and/or weaknesses. Powered by an energy-dense fuel (e.g., but not limited to, ethanol, diesel, biodiesel, petrol or gasoline, a liquid derived from fossil fuels), the ICE delivers an excellent power-to-weight ratio with few disadvantages. While there have been and still are many stationary applications, the real strength of internal combustion engines is in mobile applications and they dominate as a power supply for vehicles, such as, but not limited to, land, air, and marine, or amphibious, vehicles, or combinations thereof.

[0079] Accordingly, any suitable ICE, ECE, or electric motor (EM) can be used herein for providing power as a torque or power source any suitable vehicle comprising a clutchless c-axial hybrid transmission system as described herein.

[0080] Electric motors (EM) can be used, including any suitable EM. An EM is any machine that converts electricity into a mechanical motion. An AC motor is an electric motor that is driven by alternating current, which can include, but is not limited to, (i) a synchronous motor, an alternating current motor distinguished by a rotor spinning with coils passing magnets at the same rate as the alternating current and resulting magnetic field which drives it; or (ii) an induction motor (also called a squirrel-cage motor) a type of asynchronous alternating current motor where power is supplied to the rotating device by means of electromagnetic induction. A DC motor is an electric motor that runs on direct current electricity, which can include, but is not limited to, (i) a brushed DC electric motor, an internally commutated electric motor designed to be run from a direct current torque or power source; and (ii) a brushless DC motor, a synchronous electric motor, which is powered by direct current electricity and has an electronically controlled commutation system, instead of a mechanical commutation system based on brushes.

[0081] Vehicles: Any suitable vehicle can use a clutchless c-axial hybrid transmission system, wherein the vehicle can include, but is not limited to, an unmanned aeronautical vehicle, a manned aeronautical vehicle, an inboard marine vehicle, an outboard marine vehicle, a two wheeled land or amphibious vehicle, a multi-wheeled land or amphibious vehicle, or any combination thereof. Non-limiting examples of vehicles that can be used with a clutchless c- axial hybrid transmission system include aeronautical vehicles or aircraft, such as unmanned aerial vehicles, unmanned aircraft systems, manned aircraft,

[0082] Aircraft. Any suitable aeronautical vehicle or aircraft can use a clutchless c-axial hybrid transmission system, wherein the vehicle can include, but is not limited to, an unmanned aeronautical vehicle, or a manned aeronautical vehicle, as known in the art or as described herein. An aeronautical vehicle or aircraft is a vehicle which is able to fly by being supported by the air, or in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Any suitable aeronautical vehicle or aircraft can be used with a clutchless hybrid transmission.

[0083] Heavier than air - aerodynes suitable for use with a clutchless c-axial hybrid transmission system can include any type with at least two torque or power sources. Heavier- than-air aircraft must find some way to push air or gas downwards, so that a reaction occurs (by Newton's laws of motion) to push the aircraft upwards. This dynamic movement through the air is the origin of the term aerodyne. There are two ways to produce dynamic upthrust:

aerodynamic lift, and powered lift in the form of engine thrust. Aerodynamic lift is the most common, with fixed-wing aircraft being kept in the air by the forward movement of wings, and rotorcraft by spinning wing-shaped rotors sometimes called rotary wings. A wing is a flat, horizontal surface, usually shaped in cross-section as an aerofoil. To fly, air must flow over the wing and generate lift. A flexible wing is a wing made of fabric or thin sheet material, often stretched over a rigid frame.

[0084] With powered lift, the aircraft directs its engine thrust vertically downwards. VTOL (vertical takeoff and landing) is applied to aircraft that can take off and land vertically. Most are rotorcraft. Others take off and land vertically using powered lift and transfer to aerodynamic lift in steady flight. Similarly, STOL stands for short takeoff and landing. Some VTOL aircraft often operate in a short take off/vertical landing mode known as STOVL.

[0085] Fixed-wing. Besides the method of propulsion, fixed-wing aircraft are generally characterized by their wing configuration. The most important wing characteristics are: Number of wings - Monoplane, biplane, etc; Wing support - Braced or cantilever, rigid or flexible; Wing planform - including aspect ratio, angle of sweep and any variations along the span (including the important class of delta wings); Location of the horizontal stabilizer, if any; Dihedral angle - positive, zero or negative (anhedral).

[0086] A variable geometry aircraft can change its wing configuration during flight. A flying wing has no fuselage, though it may have small blisters or pods. The opposite of this is a lifting body which has no wings, though it may have small stabilizing and control surfaces. Most fixed-wing aircraft feature a tail unit or empennage incorporating vertical, and often horizontal, stabilizing surfaces. Seaplanes are aircraft that land on water, and they fit into two broad classes: Flying boats are supported on the water by their fuselage. A float plane's fuselage remains clear of the water at all times, the aircraft being supported by two or more floats attached to the fuselage and/or wings. Some examples of both flying boats and float planes are amphibious, being able to take off from and alight on both land and water. Some consider wing-in-ground-effect vehicles to be fixed-wing aircraft, others do not. These craft "fly" close to the surface of the ground or water. Man-powered aircraft also rely on ground effect to remain airborne, but this is only because they are so underpowered— the airframe is theoretically capable of flying much higher.

[0087] Rotorcraft, or rotary-wing aircraft, use a spinning rotor with aerofoil section blades (a rotary wing) to provide lift. Types include helicopters, auto gyros and various hybrids such as gyro dynes and compound rotorcraft. Helicopters have powered rotors. The rotor is driven (directly or indirectly) by an engine and pushes air downwards to create lift. By tilting the rotor forwards, the downwards flow is tilted backwards, producing thrust for forward flight. Auto gyros or gyroplanes have unpowered rotors, with a separate power plant to provide thrust. The rotor is tilted backwards. As the auto gyro moves forward, air blows upwards across the rotor, making it spin.(cf. Autorotation) This spinning dramatically increases the speed of airflow over the rotor, to provide lift.

[0088] Gyro dynes are a form of helicopter, where forward thrust is obtained from a separate propulsion device rather than from tilting the rotor. The definition of a 'gyro dyne' has changed over the years, sometimes including equivalent auto gyro designs. The Heliplane is a similar system.

[0089] Compound rotorcraft have wings which provide some or all of the lift in forward flight. Compound helicopters and compound auto gyros have been built, and some forms of gyroplane may be referred to as compound gyroplanes. They are nowadays classified as powered lift types and not as rotorcraft. Tilt rotor aircraft have their rotors horizontal for vertical flight, and pivot the rotors vertically like a propeller for forward flight. Some rotorcraft have reaction- powered rotors with gas jets at the tips, but most have one or more lift rotors powered from engine-driven shafts.

[0090] Unmanned aerial vehicles or unmanned aircraft systems suitable for use with a clutchless c-axial hybrid transmission system can include any type with at least two torque or power sources. An unmanned aerial vehicle (UAV); also known as a remotely piloted vehicle or PV, or Unmanned Aircraft System (UAS), is an aircraft that is flown by a pilot or a navigator (now called combat systems officer) depending on the different Air Forces, however, without a human crew on board the aircraft. To distinguish UAVs from missiles, a UAV is defined as a reusable, remotely crewed aircraft capable of controlled, sustained, level flight and powered by a jet, reciprocating engine, or other sources of propulsion. There are a wide variety of UAV shapes, sizes, configurations, and characteristics. UAVs come in two varieties: some are controlled from a remote location, and others fly autonomously based on pre-programmed flight plans using more complex dynamic automation systems. Currently, military UAVs perform reconnaissance as well as attack missions. UAVs are also used in civil applications, such as firefighting or nonmilitary security and other work, such as surveillance. The abbreviation UAV has been expanded in some cases to UAVS (unmanned-aircraft vehicle system). In the United States, the Federal Aviation Administration has adopted the generic class unmanned aircraft system (UAS) originally introduced by the U.S. Navy to reflect the fact that these are not just aircraft, but systems, including ground stations and other elements. Wagner, William. Lightning Bugs and other Reconnaissance Drones; The can-do story of Ryan's unmanned spy planes. 1982, Armed Forces Journal International, in cooperation with Aero Publishers, Inc., entirely incorporated herein by reference.

[0091] Although most UAVs are fixed-wing aircraft, rotorcraft designs such as this MQ-8B Fire Scout can also be used. UAVs typically fall into one of six functional categories (although multi- role airframe platforms are becoming more prevalent): (i) Target and decoy - providing ground and aerial gunnery a target that simulates an enemy aircraft or missile; (ii) Reconnaissance - providing battlefield intelligence; (iii) Combat - providing attack capability for high-risk missions (see Unmanned combat air vehicle); (iv) Logistics - UAVs specifically designed for cargo and logistics operation; (v) Research and development - used to further develop UAV technologies to be integrated into field deployed UAV aircraft; and (vi) Civil and Commercial UAVs - UAVs specifically designed for civil and commercial applications. UAVs can also be categorized in terms of range/altitude and the following has been advanced as relevant at such industry events as Pare Aberporth Unmanned Systems forum: (a) Handheld 2,000 ft (600 m) altitude, about 2 km range; (b) Close 5,000 ft (1 ,500 m) altitude, up to 10 km range; (c) NATO type 10,000 ft (3,000 m) altitude, up to 50 km range; (d) Tactical 18,000 ft (5,500 m) altitude, about 160 km range; (e) MALE (medium altitude, long endurance) up to 30,000 ft (9,000 m) and range over 200 km; and (f) HALE (high altitude, long endurance) over 30,000 ft (9,100 m) and indefinite range.

[0092] In a third classification system, the modern concept of U.S. military UAVs is to have the various aircraft systems work together in support of personnel on the ground. The integration scheme is described in terms of a "Tier" system, and is used by military planners to designate the various individual aircraft elements in an overall usage plan for integrated operations. The Tiers do not refer to specific models of aircraft, but rather roles for which various models and their manufacturers competed. The U.S. Air Force and the U.S. Marine Corps each has its own tier system, and the two systems are themselves not integrated.

[0093] UAS, or unmanned aircraft system, is the official United States Federal Aviation

Administration (FAA) term for an unmanned aerial vehicle. The inclusion of the term aircraft emphasizes that regardless of the location of the pilot and flight crew, the operations must comply with the same regulations and procedures as do those aircraft with the pilot and flight crew onboard. The official acronym 'UAS' is also used by International Civil Aviation

Organization (ICAO) and other government aviation regulatory organizations. UAVs perform a wide variety of functions. The majority of these functions are some form of remote sensing; this is central to the reconnaissance role most UAVs fulfill. UAV functions can also include interaction and transport. UAV remote sensing functions include electromagnetic spectrum sensors, biological sensors, and chemical sensors. A UAVs electromagnetic sensors typically include visual spectrum, infrared, or near infrared cameras as well as radar systems. Other electromagnetic wave detectors such as microwave and ultraviolet spectrum sensors may also be used. Biological sensors are sensors capable of detecting the airborne presence of various microorganisms and other biological factors. Chemical sensors use laser spectroscopy to analyze the concentrations of each element in the air. UAVs can transport goods using various means based on the configuration of the UAV itself. Most payloads are stored in an internal payload bay somewhere in the airframe. For many helicopter configurations, external payloads can be tethered to the bottom of the airframe. With fixed wing UAVs, payloads can also be attached to the airframe, but aerodynamics of the aircraft with the payload must be assessed. For such situations, payloads are often enclosed in aerodynamic pods for transport.

[0094] As a non-limiting example of scientific research, the RQ-7 Shadow is capable of delivering a 20 lb (9.1 kg) medical or other supply canister or payload to front-line troops.

Unmanned aircraft are uniquely capable of penetrating areas which may be too dangerous for piloted craft. The National Oceanic and Atmospheric Administration (NOAA) began utilizing the Aerosonde unmanned aircraft system in 2006 as a hurricane hunter. AAI Corporation subsidiary Aerosonde Pty Ltd. of Victoria (Australia), designs and manufactures the 35-pound system, which can fly into a hurricane and communicate near-real-time data directly to the National Hurricane Center in Florida. As non-limiting examples of search and rescue, UAVs can be used, e.g., the successful use of UAVs during the 2008 hurricanes that struck Louisiana and Texas, and Predators, operating between 18,000-29,000 feet above sea level, performed search and rescue and damage assessment. Payloads carried were an optical sensor (which is a daytime and infra-red camera) and a synthetic aperture radar. The Predator's SAR is a sophisticated all-weather sensor capable of providing photographic-like images through clouds, rain or fog, and in daytime or nighttime conditions; all in real-time. As a non-limiting example of endurance applications, RQ-4 Global Hawk, a high-altitude reconnaissance UAV capable of 36 hours continuous flight time. Because UAVs are not burdened with the physiological limitations of human pilots, they can be designed for maximized on-station times. The maximum flight duration of unmanned, aerial vehicles varies widely. Internal-combustion-engine aircraft endurance depends strongly on the percentage of fuel burned as a fraction of total weight (the Breguet endurance equation), and so is largely independent of aircraft size. Solar-electric UAVs can be used to complement ICE powered flight using a clutchless c-axial hybrid transmission system .

[0095] Manned aeronautical vehicles. Manned aircraft included in aeronautical vehicles include any aircraft that can use a clutchless c-axial hybrid transmission system with at least two torque or power sources. Non-limiting examples of such aircraft include fixed wing, rotorcraft, rotary wing, and any other type of manned aeronautical vehicle. Aircraft engines suitable for use with a clutchless c-axial hybrid transmission system can include any suitable aircraft engine as a torque or power source for a propulsion drive shaft that is driven by at least two torque or power sources operably linked to the clutchless c-axial hybrid transmission system. The process of developing an engine is one of compromises. Engineers design specific attributes into engines to achieve specific goals. Aircraft are one of the most demanding applications for an engine, presenting multiple design requirements, many of which conflict with each other. An aircraft engine must be: (i) reliable, as losing power in an airplane is a substantially greater problem than in an automobile. Aircraft engines operate at temperature, pressure, and speed extremes, and therefore need to perform reliably and safely under all reasonable conditions; (ii) light weight, as a heavy engine increases the empty weight of the aircraft and reduces its payload; (iii) powerful, to overcome the weight and drag of the aircraft; (iv) small and easily streamlined; large engines with substantial surface area, when installed, create too much drag; (v) field repairable, to keep the cost of replacement down; (vi) fuel efficient to give the aircraft the range the design requires; and (vii) capable of operating at sufficient altitude for the aircraft. Aircraft spend the vast majority of their time travelling at high speed. This allows an aircraft engine to be air cooled, as opposed to requiring a radiator. With the absence of a radiator, aircraft engines can boast lower weight and less complexity. The amount of air flow an engine receives is usually designed according to expected speed and altitude of the aircraft in order to maintain the engine at the optimal temperature. Aircraft operate at higher altitudes where the air is less dense than at ground level. As engines need oxygen to burn fuel, a forced induction system such as turbocharger or supercharger is appropriate for aircraft use. This does bring along the usual drawbacks of additional cost, weight and complexity. V engines. Cylinders in this engine are arranged in two in-line banks, tilted 30-60 degrees apart from each other. The vast majority of V engines are water-cooled. The V design provides a higher power-to-weight ratio than an inline engine, while still providing a small frontal area. Radial engines. This type of engine has one or more rows of cylinders arranged in a circle around a centrally-located crankcase. Each row must have an odd number of cylinders in order to produce smooth operation. A radial engine has only one crank throw per row and a relatively small crankcase, resulting in a favorable power to weight ratio. Because the cylinder arrangement exposes a large amount of the engine's heat radiating surfaces to the air and tends to cancel reciprocating forces, radials tend to cool evenly and run smoothly. Flat engine. An opposed-type engine has two banks of cylinders on opposite sides of a centrally located crankcase. The engine is either air cooled or liquid cooled, but air cooled versions predominate. Opposed engines are mounted with the crankshaft horizontal in airplanes, but may be mounted with the crankshaft vertical in helicopters. Due to the cylinder layout, reciprocating forces tend to cancel, resulting in a smooth running engine. Unlike a radial engine, an opposed engine does not experience any problems with hydrostatic lock. Opposed, air-cooled four and six cylinder piston engines are by far the most common engines used in small general aviation aircraft requiring up to 400 horsepower (300 kW) per engine.

[0096] Marine vehicles. A marine vehicle suitable for use with a clutchless c-axial hybrid transmission system can include any type of suitable boat. A boat is a watercraft designed to float or plane, to provide passage of people, animals, and/or payloads across water. This water can be inland, coastal, or at sea. In naval terms, a boat is something small enough to be carried aboard another vessel (a ship). Strictly speaking and uniquely a submarine is a boat as defined by the Royal Navy. Non-limiting examples of marine vehicles include any inboard or outboard powered boat or amphibious vehicle, comprising at least two torque or power sources, including ICEs, EM, or other torque or power source. Specific non-limiting examples include, but are not limited to, one or more of the following: airboat, ambulance, banana boat, barge, bass boat, bow rider, cabin cruiser, car-boat, catamaran, clipper ship, cruise ship, cruiser, cruising trawler, dinghy, dory, dragger, dredge, drifter (fishing), drifter (naval), ferry, fishing boat, houseboat, hydrofoil, hydroplane, jet boat, jet ski, launch, landing craft, longboat, luxury yacht, motorboat, motor launch (naval), personal water craft (pwc), pleasure barge, powerboat, riverboat, runabout, rowboat, sailboat, schooner, scow, sharpie, ship, ski boat, skiff, steam boat, slipper launch, sloop, speed boat, surf boat, swift boat, traditional fishing boats, trimaran, trawler (fishing), trawler (naval), trawler (recreational), tugboat, wakeboard boat, water taxi, whaleboat, yacht, and/or yawl. Boat or marine vehicle propulsion can include any suitable type used with a clutchless c-axial hybrid transmission system with at least two torque or power sources, such as with an EM, but are not limited to, motor powered screws, inboard (such as internal combustion (e.g., but not limited to, gasoline, diesel, heavy fuel oil) steam (coal, fuel oil), nuclear (for submarines and large naval ships), inboard/outboard (e.g., but not limited to, gasoline, electric, steam and diesel), outboard (e.g., but not limited to, gasoline, electric, steam and diesel), electric, paddle wheel, and water jet (e.g., but not limited to, personal water craft, jet boats). See, e.g., McGrail, Sean (2001 ). Boats of the World. Oxford, UK: Oxford University Press. ISBN 0-19-814468-7, entirely incorporated herein by reference. Inboard Motors: An inboard motor is a marine propulsion system for boats. As opposed to an outboard motor where an engine is mounted outside of the hull of the craft, an inboard motor is an engine enclosed within the hull of the boat, usually connected to a propulsion screw by a drive shaft. Sizes: Inboard motors may be of several types, suitable for the size of craft they are fitted to. Boats can use one cylinder to v12 engines, depending if they are used for racing or trolling. Small craft. For pleasure craft, such as sailboats and speedboats, both diesel and gasoline engines are used. Many inboard motors are derivatives of automobile engines, known as marine automobile engines. The advent of the stern drive propulsion leg improved design so that auto engines could easily power boats. Large craft: For larger craft, including ships (where outboard propulsion would in any case not be suitable) the propulsion system may include many types, such as diesel, gas turbine, or even fossil-fuel or nuclear-generated steam. Some early models used coal for steam-driven ships. Cooling. Aircraft engines were later used in boats. Some inboard motors are freshwater cooled, while others have a raw water cooling system where water from the lake, river or sea is pumped by the engine to cool it. However, as seawater is corrosive, and can damage engine blocks and cylinder heads, some seagoing craft have engines which are indirectly cooled via a heat exchanger. Other engines, notably small single and twin cylinder diesels specifically designed for marine use, use raw seawater for cooling and zinc sacrificial anodes are employed protect the internal metal castings. A stern drive or inboard/outboard drive (I/O) is another suitable form of marine propulsion for use with an additional torque or power source, such as an EM. The engine is located inboard just forward of the transom (stern) and provides power to the drive unit located outside the hull. This drive unit (or outdrive) resembles the bottom half of an outboard motor, and is composed of two sub-units: the upper unit contains a drive shaft that connects through the transom to the engine and transmits power to a 90-degree-angle gearbox; the lower unit bolts onto the bottom of the upper unit and contains a vertical drive shaft that transmits power from the upper unit gearbox down to another 90-degree-angle gearbox in the lower unit, which connects to the propeller shaft. Thus, the outdrive carries power from the inboard engine, typically mounted above the waterline, outboard through the transom and downward to the propeller below the waterline. The outdrive can be matched with a variety of engines in the appropriate power range; upper and lower units can often be purchased separately to customize gear ratios and propeller RPM, and lower units are also available with counter-rotating gearing to provide balanced torque in dual-drive installations. The boat is steered by pivoting the outdrive, just like with an outboard motor, and no rudder is needed. The engine itself is usually the same as those used in true inboard systems, historically the most popular in North America was marinized versions of Chevrolet and Ford V-8 automotive engines. In Europe diesel engines are more popular with up to 370 hp available with Volvo Pentas D6A-370. Brands of sterndrive include Volvo Penta (part of the Volvo Group) and MerCruiser (produced by Brunswick Corporation's Mercury Marine, which also manufactures outboard motors). Advantages of the sterndrive system versus outboards include higher available horsepower per engine and a clean transom with no cutouts for the outboard installation and no protruding power head, which makes for easier ingress and egress for pleasure boat passengers and for easier fishing. Advantages of the sterndrive system versus inboards include simpler engineering for boat builders, eliminating the need for them to design prop shaft and rudder systems; also, a significant space savings with the engine mounted all the way aft, freeing up the boat's interior volume for occupancy space. An outboard motor is a propulsion system for boats that can be used as a torque or power source for clutchless c-axial hybrid transmission system, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom and are the most common motorized method of propelling small watercraft. As well as providing propulsion, outboards provide steering control, as they are designed to pivot over their mountings and thus control the direction of thrust. The skeg also acts as a rudder when the engine is not running. Compared to inboard motors, outboard motors can be easily removed for storage or repairs. When boats are out of service or being drawn through shallow waters, outboard motors can be tilted up (tilt forward over the transom mounts) to elevate the propeller and lower unit out of the water to avoid accumulation of seaweed, underwater hazards such as rocks, and to clear road hazards while trailering. Small outboard motors, up to 15 horsepower or so are easily portable. They are affixed to the boat via clamps, and thus easily moved from boat to boat. These motors typically use a manual pull start system, with throttle and gearshift controls mounted on the body of the motor, and a tiller for steering. The smallest of these can weigh as little as 12 kilograms (26 lb), have integral fuel tanks, and provide sufficient power to move a small dinghy at around 8 knots (15 km/h; 9.2 mph) This type of motor is typically used: to power small craft such as jon boats, dinghies, canoes, etc; to provide auxiliary power for sailboats; for trolling aboard larger craft, as small outboards are typically more efficient at trolling speeds. In this application, the motor is frequently installed on the transom alongside and connected to the primary outboard to enable helm steering. Large outboards are usually bolted to the transom (or to a bracket bolted to the transom), and are linked to controls at the helm. These range from 2- 3- and 4-cylinder models generating 15 to 135 horsepower suitable for hulls up to 17 feet (5.2 m) in length, to powerful V-6 and V-8 cylinder blocks rated up to 350 hp (260 kW), with sufficient power to be used on boats of 18 feet (5.5 m) or longer. Electric-Powered motors are commonly referred to as "trolling motors" or "electric outboard motors", electric outboards can be used as a torque or power source for a clutchless c-axial hybrid transmission system, e.g., but not limited to, small craft or on small lakes, as a secondary means of propulsion on larger craft, and as repositioning thrusters while fishing for bass and other freshwater species, and any other application where their quietness, and ease of operation and zero emissions outweigh the speed and range deficiencies. Diesel outboards are also available but their weight and cost make them rare. Pump-jet propulsion is available as an option on most outboard motors. Although less efficient than an open propeller, they are particularly useful in applications where the ability to operate in very shallow water is important. They also eliminate the laceration dangers of an open propeller. [0097] Operational Considerations. Motor mounting height on the transom is an important factor in achieving optimal performance. The motor should be as high as possible without ventilating or loss of water pressure. This minimizes the effect of hydrodynamic drag while underway, allowing for greater speed. Generally, the anti-ventilation plate should be about the same height as, or up to two inches higher than, the keel, with the motor in neutral trim. Trim is the angle of the motor in relation to the hull, as illustrated below. The ideal trim angle is the one in which the boat rides level, with most of the hull on the surface instead of plowing through the water. If the motor is trimmed out too far, the bow will ride too high in the water. With too little trim, the bow rides too low. The optimal trim setting will vary depending on many factors including speed, hull design, weight and balance, and conditions on the water (wind and waves). Many large outboards are equipped with power trim, an electric motor on the mounting bracket, with a switch at the helm that enables the operator to adjust the trim angle on the fly. In this case, the motor should be trimmed fully in to start, and trimmed out (with an eye on the tachometer) as the boat gains momentum, until it reaches the point just before ventilation begins or further trim adjustment results in an RPM increase with no increase in speed. Motors not equipped with power trim are manually adjustable using a pin called a topper tilt lock.

Ventilation is a phenomenon that occurs when surface air or exhaust gas (in the case of motors equipped with through-hub exhaust) is drawn into the spinning propeller blades. With the propeller pushing mostly air instead of water, the load on the engine is greatly reduced, causing the engine to race and the prop to spin fast enough to result in cavitation, at which point little thrust is generated at all. The condition continues until the prop slows enough for the air bubbles to rise to the surface. The primary causes of ventilation are: motor mounted too high, motor trimmed out excessively, damage to the ant ventilation plate, damage to propeller, foreign object lodged in the diffuser ring. Cavitation as it relates to outboard motors is often the result of a foreign object such as marine vegetation caught on the lower unit interrupting the flow of water into the propeller blades. See, e.g., but not limited to, Carlton, John S., Marine Propellers and Propulsion, Elsevier, Ltd., 1994, ISBN 978-07506-8150-6, which is entirely incorporated herein by reference.

[0098] Motorcycles and related two wheel vehicles suitable for use with a clutchless c-axial hybrid transmission system can include any type of two wheeled vehicle with at least two torque or power sources. A motorcycle (also called a motorbike, bike, or cycle) is a single-track, engine-powered, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.

[0099] Construction. Motorcycle construction is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in the performance, cost, and aesthetics desired by the designer. With some exceptions, construction of modern mass- produced motorcycles has standardized on a steel or aluminum frame, telescopic forks holding the front wheel, and disc brakes. Some other body parts, designed for either aesthetic or performance reasons can be added. A gas powered engine, typically consisting of between one and four cylinders (and less commonly, up to eight cylinders), is coupled to a manual five- or six- speed sequential transmission drives the swing arm-mounted rear wheel by a chain, drive shaft or belt.

[0100] Dynamics. Different types of motorcycles have different dynamics and these play a role in how a motorcycle performs in given conditions. For example, one with a longer wheelbase provides the feeling of more stability by responding less to disturbances. Motorcycle tires have a large influence over handling. Motorcycles must be leaned in order to make turns. This lean is induced by the method known as counter steering, in which the rider steers the handlebars in the direction opposite of the desired turn. See, e.g., but not limited to, Foale, Tony (2006).

Motorcycle Handling and Chassis Design. Tony Foale Designs, pp. 4-1. ISBN 978-84-933286- 3-4; Motorcycle Design and Technology. Minneapolis: MotorBooks/MBI Publishing Company, pp. 34-35. ISBN 9780760319901 ; Cossalter, Vittore (2006). Motorcycle Dynamics. Lulu. ISBN 978-1-4303-0861 -4; Gaetano, Cocco (2004), each entirely incorporated herein by reference. There are many systems for classifying types of motorcycles, describing how the motorcycles are put to use, or the designer's intent, or some combination of the two. Six main categories are widely recognized: cruiser, sport, touring, standard, dual-purpose, and dirt bike. Sometimes sport touring motorcycles are recognized as a seventh category, and strong lines are sometimes drawn between motorcycles and their smaller cousins, mopeds, scooters and underbones.

[0101] Scooters, underbones, and mopeds. Scooter engine sizes range smaller than motorcycles, 50-650 cc (3.1^40 cu in), and have all-enclosing bodywork that makes them cleaner and quieter than motorcycles, as well as having more built-in storage space. Automatic clutches and continuously variable transmissions (CVT) make them easier to learn and to ride. Scooters usually have smaller wheels than motorcycles. Scooters usually have the engine as part of the swing arm, so that their engines travel up and down with the suspension.

Underbones are small-displacement motorcycle with a step-through frame, descendants of the original Honda Super Cub. They are differentiated from scooters by their larger wheels and their use of foot pegs instead of a floorboard. They often feature a gear shifter with an automatic clutch. The moped used to be a hybrid of the bicycle and the motorcycle, equipped with a small engine (usually a small two-stroke engine up to 50 cc, or an electric motor) and a bicycle drivetrain, and motive power can be supplied by the engine, the rider, or both. Other non- limiting types of small motorcycles include the monkey bike, welbike, and minibike. See, e.g., but not limited to, Maher, Kevin; Greisler, Ben (1998), Chilton's Motorcycle Handbook, Haynes North America, pp. 2.2-2.18, ISBN 0801990998; Bennett, Jim (1995), The Complete Motorcycle Book: A Consumer's Guide, Facts on File, pp. 15-16, 19-25, ISBN 0816028990; Stermer, Bill (2006), Street bikes: Everything You Need to Know, Saint Paul, Minnesota: Motorbooks Workshop/MBI, pp. 8-17, ISBN 0760323623, each of which is entirely incorporated herein by reference.

[0102] An amphibious vehicle (or simply amphibian), is a vehicle or craft, that is a means of transport, viable on land as well as on water -just like an amphibian. This definition applies equally to any land and water transport, small or large, powered or unpowered, ranging from amphibious bicycles, ATVs, cars, buses, trucks, RVs, and military vehicles, all the way to the very largest hovercraft. Classic landing craft are generally not considered amphibious vehicles, although they are part of amphibious assault. Nor are Ground effect vehicles, such as

Ekranoplans. The former do not offer any real land transportation at all - the latter (aside from completely disconnecting from the surface, like a fixed-wing aircraft) will probably crash on all but the flattest of landmasses.

[0103] For propulsion in or on the water some vehicles simply make do by spinning their wheels or tracks, while others can power their way forward more effectively using (additional) screw propeller(s) or water jet(s). Most amphibians will work only as a displacement hull when in the water - only a small number of designs have the capability to raise out of the water when speed is gained, to achieve high velocity hydroplaning, skimming over the water surface like speedboats.

[0104] ATV's. Amongst the smallest non-air-cushioned amphibious vehicles are amphibious bicycles, and ATVs. Although the former are still an absolute rarity, the latter saw significant popularity in North America during the nineteen sixties and early seventies. Typically an Amphibious ATV or AATV is a small, lightweight, off-highway vehicle, constructed from an integral hard plastic or fiberglass bodytub, fitted with six (sometimes eight) driven wheels, with low pressure, balloon tires. With no suspension (other than what the tires offer) and no steering wheels, directional control is accomplished through skid-steering - just as on a tracked vehicle - either by braking the wheels on the side where you want to turn, or by applying more throttle to the wheels on the opposite side. Most contemporary designs use garden tractor type engines that will provide roughly 25 mph top speed on land. Constructed this way, an AATV will float with ample freeboard and is capable of traversing swamps, ponds and streams as well as dry land. On land these units have high grip and great off-road ability that can be further enhanced with an optional set of tracks that can be mounted directly onto the wheels. Although the spinning action of the tires is enough to propel the vehicle through the water - albeit slowly - outboard motors can be added for extended water use. Current AATV manufacturers are Argo, Land Tamer, MAX ATVs and Triton. Recently some efforts have been made toward amphibious ATVs of the straddled variety. Others include the add-on inflatable pontoon kit that can be installed on any quad-bike ATV with front and rear metal frame racks and at least 14" water fording ability.

[0105] Skied vehicles. Any suitable vehicle with skies can also be used with a clutchless c- axial hybrid transmission system. The most common type of skied vehicle is a snowmobile, also known as a snow machine, sled, or skimobile, is a land vehicle for travel on various surfaces that are compatible with the use of skies, such as snow, ice or water, and also are used with other surfaces, such as grass, dirt, and asphalt, sometimes with modifications for the alternative surfaces. Designed to be operated on snow and ice, they require no road or trail. Design variations enable some machines to operate in deep snow or forests; most are used on open terrain, including lakes or driven on paths or trails. Usually built to accommodate a driver and optional additional passengers, their use is much like motorcycles and All-terrain vehicles (ATVs), usually intended for winter use on snow-covered ground and frozen ponds and waterways. They have no enclosure other than a windshield and the engine normally drives a continuous track or tracks at the rear; skis usually at the front provide directional control. Early snowmobiles used rubber tracks, but modern snowmobiles typically have tracks made of a Kevlar composite. Snowmobiles can optionally be powered by two-stroke or four-stroke gasoline/petrol internal combustion engines, with a combination of an electric motor. The contemporary types of recreational riding forms are known as Snow cross/racing, trail riding, freestyle, mountain climbing, boondocking, carving, ditch banging and grass drags. Summertime activities for snowmobile enthusiasts include drag racing on grass, asphalt strips, or even across water.

[0106] A clutchless co-axial hybrid transmission system vehicle can include where the propulsion drive shaft drives the propulsion of the vehicle. A drive shaft can drive the propulsion of the vehicle based on any suitable method which can include direct or indirect linkage to the propulsion mechanism used. An indirect linkage can include any suitable linkage that transfers at least a part of the mechanical energy from the drive shaft to the propulsion system. Non- limiting examples of indirect linkage include, but are not limited to, at least one, or one or more of a transmission, a differential, a gearbox, a gear, a torque converter, a transfer gear or case, or any known suitable type of linkage. Any suitable linkage can include the use of a, at least one, or one or more of, a drive shaft, a chain, a belt, a cam, a transfer plate, a rotor, and the like.

[0107] In optional embodiments, a hybrid propulsion system can exclude one or more of the following: a hydraulic motor, a hydraulic clutch, a clutch, a hydraulic drive motor, a high pressure accumulator, a low pressure accumulator, a hydraulic pump for a hydraulic drive motor system, a variable orbital path transmission component, an orbital path transmission component, a variable ratio transmission component, radially sliding or stepping drive or driven gears, orbital path sun gears, orbital path ring gears, orbital path planetary gears, variable orbital path sun gears, variable orbital path ring gears, variable orbital path planetary gears, orbital cycle gears, partial orbital cycle drive or driven gears, orbital cycle, partial orbital cycle, offset ring gears, offset sun gears, offset planetary gears, radially expandable gears, radially expandable drive gears, a two-stage planetary gear transmission, first and second stage planetary gear transmissions, planetary gears meshed with more than one sun gear, an alternator, an accessory motor transmission, accessory motor gearbox, accessory motor, more than one planetary gear system, multiple planetary gear systems, a differential comprising a planetary gear system, vehicle accessory drive, accessory drive output, accessory drive output, accessory drive input, accessory drive planetary gear set, steer motor, steering motor, first clutch, second clutch, a tracked vehicle, tracked vehicle transmission, tracked vehicle transmission, tracked vehicle clutch containing transmission or gearbox, same type of power input, same type of torque or power sources, two electrical motors as torque or power sources in series or parallel arrangement, the planetary gear system is provided between the torque or power sources and perpendicular to the drive shaft; the transfer of torque between the planetary gear system and the propulsion system is via a belt or chain attached to the drive shaft; the planetary gear system is provided physically between the two torque or power sources; four wheel vehicles, and the like.

[0108] All directional references (e.g., proximal, distal, upper, lower, upward, downward, left, right, lateral, longitudinal, front, back, top, bottom, above, below, vertical, horizontal, radial, axial, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present invention, and do not create limitations, particularly as to the position, orientation, or use of the invention. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. The exemplary drawings are for purposes of illustration only and the dimensions, positions, order and relative sizes reflected in the drawings attached hereto may vary.

[0109] The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments of the invention as defined in the claims.

Although various embodiments of the claimed invention have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of the claimed invention. Other embodiments are therefore contemplated. It is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative only of particular embodiments and not limiting. Changes in detail or structure may be made without departing from the basic elements of the invention as defined in the following claims. TABLE: Component Reference

Claims

CLAIMS What is claimed is

1. A clutchless, co-axial hybrid transmission system for a vehicle, comprising components comprising:

a first propulsion device comprising a first source of torque and a first propulsion drive shaft;

a second propulsion device comprising a second source of torque and a second propulsion drive shaft,

wherein the first and second drive shafts are co-axial, such that the second drive shaft is hollow; and the first drive shaft is coaxially with and extends through the second drive shaft; a planetary gear system that provides alternating or simultaneous and clutchless power coupling between the first propulsion drive shaft and the second propulsion drive shaft;

the planetary gear system clutchlessly transferring power from the first and second propulsion drive shafts to at least one power transfer device for providing propulsion of said vehicle;

wherein the planetary gear system comprises at least one sun gear, at least two planetary gears, and at least one ring gear.

2. The clutchless co-axial hybrid transmission system of claim 1 , wherein the first drive shaft interfaces with the second drive shaft via one-way bearings.

3. The clutchless co-axial hybrid transmission system of claim 1 , further comprising at least one carrier or arm operably connected to at least one of said at least one sun gear, at least one of said two planetary gears, and at least one ring gear.

4. The clutchless co-axial hybrid transmission system of claim 1 , wherein at least one of said at least one power transfer device is operably connected to one of said at least one sun gear, at least one planetary gear, and at least one ring gear.

5. The clutchless co-axial hybrid transmission system of claim 1 , wherein said power transfer device is connected to said ring gear via said carrier or arm and said first and second sources of torque are each connected via first and second propulsion drive shafts that are concentric to each other and each operably connected a different of said planetary gear and said sun gear that drive the power transfer device, wherein said sun gear, planetary gear and said ring gear are substantially in the same plane.

6. The clutchless co-axial hybrid transmission system of claim 1 , wherein the ratio of said at least one planetary gear and said at least one sun gear is between about 0.2 and about 0.8.

7. The clutchless co-axial hybrid transmission system of claim 6, wherein the ratio of said at least one planetary gear and said at least one sun gear is about 0.5.

8. The clutchless co-axial hybrid transmission system of claim 1 , further comprising a slipper gear assembly operably attached to the power transfer device.

9. The clutchless co-axial hybrid transmission system of claim 1 , wherein the power transfer device is selected from one or more of a shaft, a propeller, a fan, a gear, a gear system, or a wheel.

10. The clutchless co-axial hybrid transmission system of claim 1 , wherein the vehicle is selected from the group consisting of an unmanned aeronautical vehicle, a manned aeronautical vehicle, an inboard marine vehicle, an outboard marine vehicle, a two wheeled land or amphibious vehicle, and a multi-wheeled land or amphibious vehicle.

11 . The clutchless co-axial hybrid transmission system of claim 1 , wherein the first and second sources of torque are provided as one internal combustion engine (ICE) and one electric motor (EM), respectively.

12. The clutchless co-axial hybrid transmission system of claim 1 , wherein said ICE and EM power said propulsion drive shaft simultaneously as a mechanically additive system.

13. The clutchless co-axial hybrid transmission system of claim 1 1 , further comprising at least one battery or electrical storing system that powers said EM.

14. The clutchless co-axial hybrid transmission system of claim 1 1 , wherein said ICE charges said battery or electrical storing system.

15. The clutchless co-axial hybrid transmission system of claim 1 , wherein said power transfer device driving the propulsion of said vehicle is via one or more of at least one transmission, at least one differential or at least one gearbox that operates at least one angle between 0 and 90 degrees.

16. The clutchless co-axial hybrid transmission system of claim 1 , further comprising a control system comprising a controller for controlling speed or torque of one or more of the first and second sources of torque, the first or second drive shafts, the planetary gear system, and the power transfer device.

17. The clutchless co-axial hybrid transmission system of claim 16, further comprising an internal or external receiver or transmitter for receiving data for the controller to regulate, change, stop, or start one or more of power input or output, gear ratios, speed, torque, fuel efficiency, connection efficiency, or power or speed transfer of one or more of the components of the clutchless co-axial hybrid transmission system.

18. The clutchless co-axial hybrid transmission system of claim 17, wherein the clutchless co-axial hybrid transmission system further comprises one or more throttles for controlling the amount of power or speed transferred from one or more of said components of the clutchless co-axial hybrid transmission system.

19. A vehicle, comprising a clutchless co-axial hybrid transmission system of claim 1.

20. The vehicle of claim 19, wherein the vehicle is selected from the group consisting of an unmanned aeronautical vehicle, a manned aeronautical vehicle, an inboard marine vehicle, an outboard marine vehicle, a two wheeled land or amphibious vehicle, and a multi-wheeled land or amphibious vehicle.

21 . A vehicle according to claim 20, wherein said vehicle is selected from an unmanned aeronautical vehicle and a manned aeronautical vehicle.