SYSTEMS AND METHODS FOR CONTROLLING A HYBRID MULTIROTOR AIRCRAFT - Patent application

Abstract

A system and method for controlling a hybrid aircraft, in which a flight control unit steers the aircraft by synchronizing an electric motor driven steering control rotor device for controlling torque forces and a separate fuel powered lift control device for controlling linear forces, providing lift control commands to control an internal combustion engine driving the lift rotor, and providing steering control commands to an electric motor driving the steering control rotor as needed to steer the vehicle.

Description

[Technical field]

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 331,301, filed April 15, 2022, the entire contents of which are incorporated by reference.

[0002] The present disclosure relates to systems and methods for providing extended range to unmanned aerial vehicles, and in particular to hybrid multi-rotor drones. [Background technology]

[0003] The world of unmanned aerial vehicles is divided into three broad groups: fixed-wing, helirotor and hybrid, and multirotor drones. Of the three groups, multirotor drones are particularly useful due to their high maneuverability, simplicity of operation, and low cost. However, multirotor drones have been limited by small payload capacity, short flight range, and low speed.

[0004] Multirotor drones have no lift other than the vertical thrust provided by the vertically oriented propellers. Therefore, to maintain stability, multirotor vehicles must control each rotor motor at very high speeds, i.e., frequencies from 50 Hertz to 600 Hertz or higher. Only electric motors, which have high response frequencies, are suitable for multirotor drones, since internal combustion engines cannot respond to such speeds. Therefore, the energy consumption of multirotor drones is very high, since the energy source of electric motors is batteries.

[0005] Limited energy storage in multirotor drones limits flight time, reduces range and restricts payload capacity relative to the maximum usable payload. Alternative energy sources such as fuel cells or gasoline generators have high losses during energy conversion and are not scalable.

[0006] Thus, there remains a need for an efficient multi-rotor copter with longer flight times, extended range, and greater load capacity. The invention described herein addresses the above-mentioned need. Summary of the Invention

[0007] According to one aspect of the subject matter disclosed herein, a system for controlling a hybrid aircraft is presented. The system may include a steering control rotor arrangement configured to control torque forces on the hybrid aircraft, a primary lift controller configured and operable to control linear forces on the hybrid aircraft, and a flight control unit configured and operable to synchronize the steering controller and the primary lift controller. Typically, the steering control rotor arrangement includes a power source, at least one electric motor, and at least one steering rotor, the lift controller includes a fuel tank, at least one internal combustion engine, and at least one lift rotor mechanism, and the flight control unit includes a synchronization manager configured and operable to synchronize the primary lift controller and the steering controller to pilot the aircraft.

[0008] Where appropriate, the flight control unit includes a stabilization controller configured and operable to receive sensor inputs and provide corrective control signals to the steering rotor mechanism.

[0009] Optionally, the stabilization controller may include at least one lift synchronization module configured and operable to control the multiple lift providers and at least one navigation synchronization module configured and operable to pilot the aircraft. The at least one lift synchronization module may include a primary lift synchronization module configured and operable to receive sensor data and generate control signals for synchronization between the multiple combustion engines of the primary lift providers. The at least one lift synchronization module may further include a secondary lift synchronization module configured and operable to receive sensor data and generate auxiliary control signals for synchronization between the multiple electric motors of the steering control rotor device to provide auxiliary lift.

[0010] Optionally, the at least one navigation synchronization module is configured and operable to receive the sensor data and generate control signals for synchronizing the at least one electric motor and the at least one steering rotor of the steering control rotor device to provide stability during maneuvering of the vehicle.

[0011] In a particular example of a control system, a steering control rotor arrangement may include four steering rotors arranged such that two steering rotors are configured to provide lift when rotating clockwise and two steering rotors are configured to provide lift when rotating counterclockwise.

[0012] Thus, the steering control rotor device may be configured to control the roll angle by synchronizing the increased rotational speed in both of the first pair of adjacent steering rotors relative to the second pair of adjacent steering rotors. Similarly, the steering control rotor device may be configured to control the pitch angle by synchronizing the increased rotational speed in both of the first pair of adjacent steering rotors relative to the second pair of adjacent steering rotors. Alternatively or additionally, the steering control rotor device may be configured to control the yaw angle by synchronizing the increased rotational speed in both of the first pair of clockwise steering rotors relative to the second pair of counterclockwise steering rotors.

[0013] Typically, the lift control device may include a first lift rotor mechanism configured to provide lift when rotating clockwise and a second lift rotor mechanism configured to provide lift when rotating counterclockwise. Where appropriate, the lift control device may include a first internal combustion engine configured and operative to drive the first lift rotor mechanism and a second internal combustion engine configured and operative to drive the second lift rotor mechanism.

[0014] Alternatively, the lift control device may include a common internal combustion engine, a first transmission line, a second transmission line, a first lift rotor mechanism, and a second lift rotor mechanism, the first lift rotor mechanism being mechanically connected to the common internal combustion engine via the first transmission line, and the second lift rotor mechanism being mechanically connected to the common internal combustion engine via the second transmission line. Thus, the second transmission line is configured and operable to drive the second lift rotor mechanism to counteract the torque of the first lift rotor mechanism. For example, the first transmission line may be configured and operable to drive the first lift rotor mechanism in a clockwise direction, and the second transmission line may be configured and operable to drive the second lift rotor mechanism in a counterclockwise direction. Additionally or alternatively, the lift control device may be configured to tilt at least one of the first lift rotor mechanism and the second lift rotor mechanism.

[0015] In another embodiment of the hybrid aircraft control system, the lift control device includes a single lift rotor mechanism.

[0016] In another aspect of the present invention, a method for controlling a hybrid multi-rotor aircraft is taught, the hybrid multi-rotor aircraft including a steering control rotor device, a lift control device, a flight control unit, and a sensor unit.

[0017] The method may include a flight control unit providing lift control commands to a lift controller, the flight control unit providing steering control commands to a steering controller, the lift controller controlling power of at least one internal combustion mechanism in accordance with the lift control commands, the at least one internal combustion mechanism driving at least one lift rotor mechanism at a desired rotational speed, thereby generating a desired linear lift force applied to the hybrid aircraft, and the steering control rotor mechanism controlling power of at least one electric motor in accordance with the steering control commands, the at least one electric motor driving at least one steering rotor mechanism at a desired rotational speed, thereby generating a desired torque force to the hybrid aircraft.

[0018] Where appropriate, driving at least one lift rotor mechanism at the required rotational speed typically comprises a common internal combustion engine driving the first lift rotor clockwise and the second lift rotor counterclockwise to counter torque of the first lift rotor mechanism. Additionally or alternatively, driving at least one lift rotor mechanism at the required rotational speed comprises the first internal combustion engine driving the first lift rotor clockwise and the second internal combustion engine driving the second lift rotor counterclockwise.

[0019] Typically, the step of controlling power of the at least one electric motor in accordance with the steering control command includes communicating a first steering control signal to the first electric motor, a second steering control signal to the second electric motor, a third steering control signal to the third electric motor, and a fourth steering control signal to the fourth electric motor. Thus, the first pair of electric motors may drive the first pair of steering rotors in a clockwise direction, and the second pair of electric motors may drive the second pair of steering rotors in a clockwise direction.

[0020] Further, the first pair of electric motors may drive the first pair of steering rotors at a first rotational speed and the second pair of electric motors may drive the second pair of steering rotors at a second rotational speed. Thus, the first pair of electric motors may be adjacent to one another and the second pair of electric motors may be adjacent to one another, thereby creating a lateral lift differential to tilt the hybrid aircraft. Additionally or alternatively, the first pair of electric motors may drive the first pair of steering rotors clockwise and the second pair of electric motors may drive the second pair of steering rotors clockwise to control a yaw moment on the hybrid aircraft.

[0021] For a better understanding of the embodiments and to show how they may be carried into effect, reference will now be made, purely by way of example, to the accompanying drawings in which:

[0022] With specific reference now to the drawings in detail, it is emphasized that the details shown are illustrative and are for the purpose of illustrative description of selected embodiments only, and are presented to provide what is believed to be the most useful and easily understood description of the principles and conceptual aspects. In this regard, there is no intention to show more detailed and structural details than are necessary for a fundamental understanding, and the description given with the drawings will make clear to those skilled in the art how various selected embodiments may be implemented. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a block diagram that generally represents selected functional elements of an embodiment of a hybrid aircraft having a fuel-powered lift control and an electric steering control. [Diagram 2] FIG. 13 is another block diagram illustrating a possible configuration of functional elements of a second embodiment of a hybrid aircraft for controlling a fuel-powered lift control and an electric steering control. [Figure 3A] FIG. 1 is an isometric view of a possible hybrid aircraft with two internal combustion engine-powered lift rotors and four electrically powered steering rotors. [Figure 3B] FIG. 1 is a plan view of a possible hybrid aircraft with two internal combustion engine-powered lift rotors and four electrically powered steering rotors. [Figure 3C] FIG. 1 is a side view of a possible hybrid aircraft with two internal combustion engine-powered lift rotors and four electrically powered steering rotors. [Figure 4A] FIG. 1 is an isometric view of an alternative hybrid aircraft having one internal combustion engine powered lift rotor with four electrically powered steering rotors. [Figure 4B] FIG. 1 is a plan view of an alternative hybrid aircraft having one internal combustion engine powered lift rotor with four electrically powered steering rotors. [Figure 4C] FIG. 1 is a side view of an alternative hybrid aircraft having one internal combustion engine powered lift rotor with four electrically powered steering rotors. [Figure 5A] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5B] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5C] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5D] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5E] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5F] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5G] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5H] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-4C illustrating possible rotor operating modes used for navigating and maneuvering. [Figure 5I] FIG. 5 is a plan view of the hybrid air vehicle of FIGS. 4A-4C illustrating possible rotor operating modes used for navigating and maneuvering. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Aspects of the present disclosure relate to unmanned aerial vehicles. In particular, the present disclosure relates to hybrid multi-rotor drones having longer flight times and extended range.

[0025] The integrated solution involves separate but synchronized devices for lift and steering control: a fuel-powered main lift control provides the main vertical thrust needed for lift, and an electric steering control provides the secondary vertical thrust and fast response time needed for steering and navigation.

[0026] Thus, in addition to stabilizing, steering and steering the vehicle, the steering control device can also compensate for the slow response time and delayed action of the combustion engine in response to control signals and, if necessary, can further provide redundancy as an auxiliary lift control device in the event of, for example, a motor failure in the primary lift control device.

[0027] The fuel-powered main lift control system may include at least one lift rotor, at least one storage tank, and at least one combustion engine configured and operable to convert fuel energy directly into mechanical motion in the rotor, thereby providing the vertical thrust required to maintain lift.

[0028] It has been found that such a fuel-powered primary lift control system can save approximately 25% of the energy consumed, compared to a system that uses electric motors to provide lift and only a fuel-powered combustion engine to generate electricity to drive the electric motor. Furthermore, because steering is provided by a separate steering rotor, the dedicated lift rotor can be fixed along one axis, with no need to adjust the propeller angle. Thus, the drone can be mechanically simple and low-cost to manufacture and maintain.

[0029] It will be appreciated that a dedicated fuel-powered lift propeller configuration may also enable a larger payload to be carried than the electric motor rotors of a typical multirotor drone. Indeed, it has been found that such a configuration may enable a useful payload that is tens of percent larger relative to the size of the vessel than a helicopter or fixed-wing configuration.

[0030] Control of the vehicle may thus be maintained by a synchronization manager configured and operable to synchronize operation of the multiple motors and rotors included in the primary lift control and steering control rotor systems.

[0031] The synchronization manager may include, for example, a lift synchronization module for controlling multiple lift providers and a navigation synchronization module. The lift synchronization module may typically involve a primary lift synchronization module that receives sensor data and uses the sensor data to generate control signals for synchronization between the multiple combustion engines of the primary lift providers. In addition, a secondary lift synchronization module may generate auxiliary control signals to the electric motors to further synchronize the auxiliary lift controllers and lift management. The navigation synchronization module may provide yet further control signals to the electric motors to synchronize the electric motors and drive the individual steering rotors to provide stability when maneuvering the vehicle.

[0032] A hybrid drone as described herein may allow for greater flexibility and scalability beyond platforms with payloads of, for example, about 40 kg / hour. Such a configuration may enable missions at twice the flight speed, which may last longer and significantly increase the range of the vehicle.

[0033] In various embodiments of the present disclosure, one or more tasks as described herein may be performed by a data processor, such as a computing platform or distributed computing system for executing a plurality of instructions. Optionally, the data processor includes or has access to volatile memory for storing instructions, data, etc. Additionally or alternatively, the data processor may have access to non-volatile storage, e.g., a magnetic hard disk, flash drive, removable media, etc., for storing instructions and / or data.

[0034] It is expressly noted that the systems and methods disclosed herein may not be limited in their application to the details of construction and arrangement of components or methods set forth in the description or illustrated in the drawings and examples, and that the systems and methods disclosed herein may be capable of other embodiments or of being implemented and carried out in various ways and techniques.

[0035] Alternative methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure. Nonetheless, the specific methods and materials are described herein for illustrative purposes only. The materials, methods, and examples are not intended to be necessarily limiting.

[0036] Reference is now made to the block diagram of Figure 1, which generally illustrates selected functional elements of an embodiment of a hybrid aircraft control system 100. Hybrid aircraft control system 100 includes an internal combustion engine powered lift control 110, an electric powered steering control 120, and a flight control unit 130.

[0037] The fuel-powered lift control system 110 includes a fuel tank 116, an internal combustion engine 114, and a lift rotor mechanism 112. The fuel tank 116 holds a reservoir of fuel, typically a hydrocarbon such as petroleum, gasoline, diesel, etc., and is typically connected to the internal combustion engine via a fuel line. The internal combustion engine 114 is mechanically configured to drive the lift rotor mechanism 112 directly or via a gear mechanism. The lift rotor mechanism 112 is typically a single propeller or multiple propeller arrangement operable to generate vertical thrust that provides lift to the vehicle.

[0038] The electric steering control system includes an electrochemical cell power supply 126, an electric motor 124, and a steering rotor mechanism 122. The electrochemical cell 126 is connected to the electric motor 124 and may be used to provide power to the electric motor 124 to drive the steering rotor mechanism 122. The steering rotor mechanism 122 includes a rotor arrangement operable to tilt the lift rotor mechanism 112 so that the vehicle may be steered as required.

[0039] Flight control unit 130 includes a synchronization manager 132, a stabilization controller 134, and a sensor unit 136. Synchronization manager 132 synchronizes lift controller 110 and steering controller 120 so that the aircraft may be steered as needed. Stabilization controller 134 provides corrective control signals to steering rotor mechanism 120, typically in response to sensor inputs from sensor unit 136, to maintain vehicle stability. Sensor unit 136 may include various sensors, such as accelerometers, cameras, orientation sensors, etc., as needed.

[0040] Reference is now made to the block diagram of Figure 2, which illustrates an example of a possible configuration of functional elements of control system 200 for the second embodiment of the hybrid aircraft. Control system 200 includes battery 226, battery monitor switchboard 231, electronic speed control 233, electric motor 224, flight control device 234, motor control unit 237, internal combustion engine 214, electronic speed control 233, and starter 235.

[0041] Flight controller 234 may provide control commands to both motor control unit 237 and electronic speed controller 233. Thus, regulated control signals may be sent to electric motor 224 to control the steering rotors and to internal combustion engine 214 to control the lift rotor mechanisms. Note that battery 226 or electrochemical cells may be monitored and recharged by internal combustion engine 214, if necessary.

[0042] 3A-3C, isometric, plan and side views are provided for illustrative purposes of a possible hybrid aircraft 300 having two fuel-powered lift rotors 312A, 312B and four electrically powered steering rotors 322A-322D.

[0043] Each of the two fuel-powered lift rotors 312A, 312B is driven by an internal combustion engine 314A, 314B. A central fuel tank 316 is connected via fuel lines 315A, 315B to a carburetor that provides a fuel-air mixture to the two internal combustion engines, which then drive the lift rotors 312A, 312B. The lift rotors 312A, 312B are mounted on fixed axles so that they cannot tilt; to tilt the lift rotors, a steering rotor arrangement tilts the entire vehicle as needed.

[0044] Each of the four motorized steering rotors 322A-322D is driven by a dedicated electric motor 324A-324D, which can be individually controlled to provide the desired thrust from each of the steering rotors 312A, 312B.

[0045] Reference is now made to Figures 4A-4C, which are isometric, plan and side views of an alternative hybrid aircraft 400 having two fuel-powered lift rotors 412A, 412B and four electrically powered steering rotors 422A-422D.

[0046] In an alternative embodiment of the hybrid vehicle, two fuel-powered lift rotors 412A, 412B are driven by a common central internal combustion engine 414 located near a central fuel tank 416. A first mechanical transmission line may be provided between the engine 414 and the first lift propeller 412A, and a second mechanical transmission line may be provided between the engine 414 and the second lift propeller 412B. Preferably, the lift propellers 412A, 412B are driven in opposite directions so that each lift propeller cancels the angular momentum of the other, thereby preventing spinning or rotation of the vehicle about the central axis.

[0047] Reference is now made to Figures 5A-5I, which are plan views illustrating possible rotor operating modes used for navigation and piloting of an alternative embodiment of the hybrid aircraft shown in Figures 4A-4C. Note that rotor direction and speed are indicated by rounded arrows, with thicker arrows representing faster propeller speeds. For ease of distinction, the movement of lift rotors 412A, 412B is represented by solid black arrows, and the movement of steering rotors 422A-422D is represented by white arrows.

[0048] 5A, the direction of motion of the aircraft 400 may be controlled by the steering rotors 422A-422D to move the vehicle to the left by operating the two right steering rotors 422B, 422C faster than the left rotors 422A, 422D. This generates more lift on the right side, banking the vehicle, thereby increasing the roll angle to the left and increasing the leftward component of the propeller thrust vector.

[0049] 5B, the direction of motion of the aircraft 400 may be controlled by the steering rotors to move the vehicle to the right by operating the two left steering rotors 422A, 422D faster than the right rotors 422B, 422C. This generates more lift on the left side, banking the vehicle, thereby increasing the roll angle to the right and increasing the rightward component of the propeller thrust vector.

[0050] Similarly, referring to Figure 5C, the direction of motion of the aircraft 400 may be controlled by the steering rotors to move the vehicle aft by operating the two forward steering rotors 422A, 422B faster than the aft rotors 422C, 422D, which generates more lift forward, tilting the vehicle so that the pitch angle increases aft and the propeller thrust vector has an increased aft component.

[0051] Similarly, referring to Figure 5D, the direction of motion of the aircraft 400 may be controlled by the steering rotors to move the vehicle forward by operating the two aft steering rotors 422C, 422D faster than the forward rotors 422A, 422B, which generates more lift at the aft, tilting the vehicle, which increases the pitch angle forward and increases the forward component of the propeller thrust vector.

[0052] Of particular note is that the orientation of each rotor is selected such that the sum of the propeller angular momentum is zero, so that the clockwise angular momentum generated by the left lift propeller 412A is exactly balanced by the counterclockwise angular momentum generated by the right lift propeller 412B. Similarly, the clockwise angular momentum generated by both the left front steering propeller 422A and the right aft steering propeller 422C is exactly balanced by the counterclockwise angular momentum generated by both the right front steering propeller 422B and the left aft steering propeller 422D.

[0053] 5E and 5F, the vehicle can be controlled to spin about the central axis by increasing the angular momentum of steering propellers 422A-422D, which can control the yaw angle as needed. This causes a counterclockwise rotation of the vehicle by increasing the rate of clockwise rotation of left front propeller 422A and right rear propeller 422C, as shown in FIG. 5E. Similarly, a clockwise rotation of the vehicle can be caused by increasing the rate of counterclockwise rotation of right front propeller 422B and left rear propeller 422D, as shown in FIG. 5F.

[0054] Note that lift propellers 412A, 412B may be utilized to control the vertical motion of the vehicle. FIG. 5G shows that during horizontal flight, the speed of lift propellers 412A, 412B is selected so that the lift exactly matches the weight of the vehicle. As shown in FIG. 5H, the vehicle may rise by increasing the speed of lift propellers 412A, 412B, which causes the lift to exceed the weight of the vehicle, resulting in a net upward force, which accelerates the vehicle upward. Similarly, as shown in FIG. 5I, by decreasing the speed of lift propellers 412A, 412B, the lift may be reduced below the weight of the vehicle, resulting in a net downward force, which accelerates the vehicle downward for descent.

[0055] It will be appreciated that certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination, or as appropriate, in any other described embodiment of the disclosure. Certain features described in the context of various embodiments should not be construed as essential features of those embodiments, unless the embodiment is inoperable without those elements.

[0056] Although the present invention has been described in conjunction with specific embodiments thereof, it is apparent that other alternatives, modifications, variations, and equivalents will become apparent to those skilled in the art. It is therefore intended to embrace all such alternatives, modifications, variations, and equivalents that fall within the spirit and broad scope of the appended claims. In addition, the various embodiments described above have been described with reference to exemplary block diagrams, flow charts, and other diagrams. As will be apparent to those skilled in the art, the illustrated embodiments and their various alternatives may be implemented without being limited to the illustrated examples. For example, the block diagrams and the accompanying description should not be construed as mandating a particular structure, layout, or configuration.

[0057] Technical notes The technical and scientific terms used herein should have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. Nevertheless, it is expected that many related systems and methods will be developed during the life of the patent that matures from this application. Thus, the scope of terms such as computing unit, network, display, memory, server, etc. is intended to include all such new technologies a priori.

[0058] As used herein, the term "about" refers to at least ±10%.

[0059] The terms "comprises," "comprising," "includes," "including," "having," and their conjugations mean "including but not limited to" and indicate that the listed elements are included, but generally do not exclude other elements. Such terms encompass the terms "consisting of" and "consisting essentially of."

[0060] The phrase "consisting essentially of" means that the composition or method may include additional components and / or steps, but only if the additional components and / or steps do not materially alter the basic and novel characteristics of the claimed composition or method.

[0061] As used herein, the singular forms "a," "an," and "the" can include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" can include a plurality of compounds, including mixtures thereof.

[0062] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or to exclude the incorporation of features from other embodiments.

[0063] The phrase "optionally" is used herein to mean "provided in some embodiments, but not provided in other embodiments." Any particular embodiment of the present disclosure may include multiple "optional" features, unless such features are inconsistent.

[0064] Whenever a numerical range is given herein, it is intended to include every recited number (fractional or integer) within the given range. The phrases "ranging between" a first indicated number and a second indicated number and "ranging from" a first indicated number to a second indicated number are used interchangeably herein and are intended to include the first and second indicated numbers and all fractional and integer numbers therebetween. It should therefore be understood that the description in range format is merely for convenience and convenience and should not be construed as a fixed limitation on the scope of the disclosure. Thus, the description of a range should be considered to specifically disclose all possible subranges and individual numbers within that range. For example, the description of a range such as 1 to 6 should be considered to specifically disclose subranges such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, etc., as well as the individual numbers within that range, e.g., 1, 2, 3, 4, 5, and 6, as well as non-integer intermediate values. This is true regardless of the breadth of the range.

[0065] It will be appreciated that certain features of the disclosure that are described for clarity in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features of the disclosure that are described for brevity in the context of a single embodiment may also be provided separately or in any suitable subcombination or as appropriate with any other described embodiment of the disclosure. Certain features described in the context of various embodiments should not be construed as essential features of those embodiments, unless the embodiment is inoperable without those elements.

[0066] While this disclosure has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will become apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.

[0067] All publications, patents, and patent applications mentioned in this specification are incorporated herein by reference in their entirety to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application should not be construed as an admission that such reference is available as prior art to the present disclosure. To the extent section headings are used, they should not be construed as necessarily limiting.

[0068] The scope of the disclosed subject matter is defined by the appended claims and includes both combinations and subcombinations of the various features described above, as well as variations and modifications thereof that will occur to those skilled in the art upon reading the foregoing description.

Claims

1. 1. A hybrid aircraft control system, comprising: a steering control rotor device configured to control torque forces on the hybrid aircraft; a primary lift control device configured and operable to control a primary linear force on the hybrid aircraft; a flight control unit configured and operable to synchronize the steering control device and the lift control device; the steering control rotor device includes a power source, at least one electric motor, and at least one steering rotor; The hybrid aircraft control system, wherein the lift control device includes a fuel tank, at least one internal combustion engine, and at least one lift rotor mechanism.

2. 2. The hybrid aircraft control system of claim 1, wherein the flight control unit includes a synchronization manager configured and operable to synchronize the primary lift control device and the steering control device to pilot the aircraft.

3. 2. The hybrid aircraft control system of claim 1, wherein the flight control unit includes a stabilization controller configured and operable to receive sensor inputs and provide corrective control signals to the steering rotor mechanism.

4. 2. The hybrid aircraft control system of claim 1, wherein the steering control rotor arrangement includes four steering rotors arranged such that two steering rotors are configured to provide lift when rotating clockwise and two steering rotors are configured to provide lift when rotating counterclockwise.

5. 5. The hybrid aircraft control system of claim 4, wherein the steering control rotor device is configured to control roll angle by synchronizing increased rotational speeds in both of a first pair of adjacent steering rotors relative to a second pair of adjacent steering rotors.

6. 5. The hybrid aircraft control system of claim 4, wherein the steering control rotor device is configured to control pitch angle by synchronizing increased rotational speeds in both of a first pair of adjacent steering rotors relative to a second pair of adjacent steering rotors.

7. 5. The hybrid aircraft control system of claim 4, wherein the steering control rotor device is configured to control yaw angle by synchronizing an increased rotational speed in both of a first pair of clockwise steering rotors relative to a second pair of counterclockwise steering rotors.

8. 2. The hybrid aircraft control system of claim 1, wherein the lift control device includes a first lift rotor mechanism configured to provide lift when rotating clockwise and a second lift rotor mechanism configured to provide lift when rotating counterclockwise.

9. 2. The hybrid aircraft control system of claim 1, wherein the lift control device includes a first internal combustion engine configured and operable to drive a first lift rotor mechanism and a second internal combustion engine configured and operable to drive a second lift rotor mechanism.

10. 2. The hybrid aircraft control system of claim 1, wherein the lift control system includes a common internal combustion engine, a first transmission line, a second transmission line, a first lift rotor mechanism, and a second lift rotor mechanism, the first lift rotor mechanism being mechanically connected to the common internal combustion engine via the first transmission line, and the second lift rotor mechanism being mechanically connected to the common internal combustion engine via the second transmission line.

11. 11. The hybrid aircraft control system of claim 10, wherein the second transmission line is configured and operable to drive the second lift rotor mechanism to counteract a torque of the first lift rotor mechanism.

12. 12. The hybrid aircraft control system of claim 11, wherein the first transmission line is configured and operable to drive the first lift rotor mechanism in a clockwise direction and the second transmission line is configured and operable to drive the second lift rotor mechanism in a counterclockwise direction.

13. The hybrid aircraft control system of claim 1 , wherein the lift control device includes a single lift rotor mechanism.

13. 1. A method for controlling a hybrid multi-rotor aircraft, the hybrid multi-rotor aircraft including a steering control rotor device, a lift control device, a flight control unit, and a sensor unit, the method comprising: the flight control unit providing lift control commands to the lift control device; the flight control unit providing steering control commands to the steering control device; the lift control device controls power of at least one internal combustion mechanism according to the lift control command; the at least one internal combustion mechanism driving at least one lift rotor mechanism at a desired rotational speed to generate a desired linear lift force applied to the hybrid aircraft; the steering control rotor device controlling power of at least one electric motor according to the steering control command; and wherein the at least one electric motor drives at least one steering rotor at a desired rotational speed, thereby generating a desired torque force on the hybrid aircraft.

14. 14. The method of claim 13, wherein the step of driving at least one lift rotor mechanism at a required rotational speed comprises driving a second lift rotor mechanism to counteract the torque of the first lift rotor mechanism.

15. 14. The method of claim 13, wherein the step of driving at least one lift rotor mechanism at a required rotational speed includes a common internal combustion engine driving a first lift rotor in a clockwise direction and a second lift rotor in a counterclockwise direction.

16. 14. The method of claim 13, wherein the step of driving at least one lift rotor mechanism at a required rotational speed includes a first internal combustion engine driving a first lift rotor in a clockwise direction and a second internal combustion engine driving a second lift rotor in a counterclockwise direction.

17. The step of controlling power of at least one electric motor in accordance with the steering control command comprises: communicating a first steering control signal to a first electric motor; communicating a second steering control signal to a second electric motor; communicating a third steering control signal to a third electric motor; and communicating a fourth steering control signal to the fourth electric motor.

18. 18. The method of claim 17, wherein a first pair of electric motors drive a first pair of steering rotors in a clockwise direction and a second pair of electric motors drive a second pair of steering rotors in a clockwise direction.

19. 18. The method of claim 17, wherein a first pair of the electric motors drive a first pair of steering rotors at a first rotational speed and a second pair of the electric motors drive a second pair of steering rotors at a second rotational speed.

20. 20. The method of claim 19, wherein a first pair of the electric motors are adjacent to one another and a second pair of the electric motors are adjacent to one another, thereby creating a lift differential to cause the hybrid aircraft to bank.

21. 20. The method of claim 19, wherein a first pair of electric motors drive a first pair of steering rotors in a clockwise direction and a second pair of electric motors drive a second pair of steering rotors in a clockwise direction, thereby controlling a yaw moment on the hybrid aircraft.

22. 1. A hybrid aircraft control system, comprising: a primary lift control device configured and operable to control a primary linear force on the hybrid air vehicle; a steering control rotor device configured to control torque forces and provide auxiliary lift control to the hybrid aircraft; a flight control unit configured and operable to synchronize the steering control device and the lift control device; the lift control system includes a fuel tank, at least one internal combustion engine, and at least one lift rotor mechanism; the steering control rotor device includes a power source, at least one electric motor, and at least one steering rotor; The flight control unit includes a synchronization manager including at least one lift synchronization module configured and operable to control multiple lift providers and at least one navigation synchronization module configured and operable to pilot the aircraft. A hybrid aircraft control system.

23. 23. The hybrid aircraft control system of claim 22, wherein the at least one lift synchronization module includes a primary lift synchronization module configured and operable to receive sensor data and generate control signals for synchronization among a plurality of combustion engines of the primary lift providers.

24. 24. The hybrid aircraft control system of claim 23, wherein the at least one lift synchronization module includes a secondary lift synchronization module configured and operable to receive sensor data and generate auxiliary control signals for synchronizing between a plurality of electric motors of the steering control rotor arrangement to provide auxiliary lift.

25. 23. The hybrid aircraft control system of claim 22, wherein the at least one navigation synchronization module is configured and operable to receive sensor data and generate control signals to synchronize the at least one electric motor and the at least one steering rotor of the steering control rotor device to provide stability during maneuvering of the vehicle.

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