Patent Application
20190310660
The invention relates to the field of aviation, namely, to flying vehicles (FV) for vertical (or near vertical) take-off and landing often referred to a hybrid vertical take-off and landing (VTOL) aircraft. These combine multicopter features with fixed wing features. Multicopters are classified as rotorcraft, as opposed to fixed-wing aircraft, because their lift is generated by a set of vertically oriented propellers (rotors) instead of fixed wing craft which generate lift using airflow across a wing.
Recent advances in electronics allowed for the production of affordable, lightweight flight controllers, accelerometers (IMU), global positioning system and cameras. This resulted in the multicopter configuration becoming popular for small unmanned aerial vehicles. Accordingly, multicopters are cheaper and more durable than conventional helicopters owing to their mechanical simplicity. Their smaller blades are also advantageous because they possess less kinetic energy, reducing their ability to cause damage and making the vehicles safer for close interaction. However, as size increases, fixed propeller multicopters develop disadvantages over conventional helicopters because increasing blade size increases their momentum. This means that changes in blade speed take longer to effectuate, which negatively impacts control. Conventional helicopters do not experience this problem as increasing the size of the rotor disk does not significantly impact the ability to control blade pitch.
Coupled with the aforementioned multicopter operation may be a fixed wing. To operate conventional fixed wing aircraft, lift is generated by airflow over the wings. This requires motion of the aircraft in a certain direction, so motors are required to provide force in a horizontal direction.
Disclosed herein are systems and method for flying a vehicle said method including the steps of powering a plurality of vertical thrustors, said vertical thrustors coupled to an airframe and positioned to provide thrust in substantially one direction. Also, powering a plurality of horizontal thrustors, said horizontal thrustors disposed to provide thrust in a direction substantially orthogonal to the thrust of the vertical thrustors. Some embodiments may include adjusting the angle of attack from a wing, said wing adjustable in both a horizontal and vertical direction. In operation, the position of the wing and the thrust from the vertical thrustors and horizontal thrustors operate together to provide for light of the flying vehicle. In some embodiments, when the horizontal velocity is sufficient, the vertical thrustors taper back and the weight of the flying vehicle will be supported at altitude by the wings, substantially using only horizontal thrust.
The vertical or horizontal thrustors include electrically driven rotor which includes a series of blades mounted around the rotor. The rotor and blades are positioned inside an input nozzle with a tapered inlet. The blades are positioned near the narrowest portion of the input nozzle. Multiple layers of blades may be employed to achieve a desired thrust—for example, and without limitation, stacked blades with varying blade pitch may be collectively driven by the electric motor.
An exit nozzle is configured to direct the output air flow from the blades to an exhaust. The exit nozzle, together with the input nozzle operate collectively as as a tube that is pinched in the middle, making a carefully balanced, asymmetric hourglass shape. The pinched tube, by altering the volume of the airflow through the nozzle, also operates to alter the pressure of the airflow through the nozzle.
Various sensors may be employed, together with different power sources to effectuate emergency flying procedures in the event a malfunction in a rotor, motor or motor controller. Setpoints for the sensors may be preprogrammed to effectuate detection of failure events. The operational procedures may be selected depending on the sensor input and put into operation in a manner to counter-act the anticipated results of the failure condition.
The construction and method of operation of the invention, however, together with additional objectives and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings and claims.
This application should be read in the most general possible form. This includes, without limitation, the following:
References to specific techniques include alternative and more general techniques, especially when discussing aspects of the invention, or how the invention might be made or used.
References to “preferred” techniques generally mean that the inventor contemplates using those techniques, and thinks they are best for the intended application. This does not exclude other techniques for the invention, and does not mean that those techniques are necessarily essential or would be preferred in all circumstances.
References to contemplated causes and effects for some implementations do not preclude other causes or effects that might occur in other implementations.
References to reasons for using particular techniques do not preclude other reasons or techniques, even if completely contrary, where circumstances would indicate that the stated reasons or techniques are not as applicable.
Furthermore, the invention is in no way limited to the specifics of any particular embodiments and examples disclosed herein. Many other variations are possible which remain within the content, scope and spirit of the invention, and these variations would become clear to those skilled in the art after perusal of this application.
The terms “effect”, “with the effect of” (and similar terms and phrases) generally indicate any consequence, whether assured, probable, or merely possible, of a stated arrangement, cause, method, or technique, without any implication that an effect or a connection between cause and effect are intentional or purposive.
The term “relatively” (and similar terms and phrases) generally indicates any relationship in which a comparison is possible, including without limitation “relatively less”, “relatively more”, and the like. In the context of the invention, where a measure or value is indicated to have a relationship “relatively”, that relationship need not be precise, need not be well-defined, need not be by comparison with any particular or specific other measure or value. For example and without limitation, in cases in which a measure or value is “relatively increased” or “relatively more”, that comparison need not be with respect to any known measure or value, but might be with respect to a measure or value held by that measurement or value at another place or time.
The term “substantially” (and similar terms and phrases) generally indicates any case or circumstance in which a determination, measure, value, or otherwise, is equal, equivalent, nearly equal, nearly equivalent, or approximately, what the measure or value is recited. The terms “substantially all” and “substantially none” (and similar terms and phrases) generally indicate any case or circumstance in which all but a relatively minor amount or number (for “substantially all”) or none but a relatively minor amount or number (for “substantially none”) have the stated property. The terms “substantial effect” (and similar terms and phrases) generally indicate any case or circumstance in which an effect might be detected or determined.
The terms “this application”, “this description” (and similar terms and phrases) generally indicate any material shown or suggested by any portions of this application, individually or collectively, and include all reasonable conclusions that might be drawn by those skilled in the art when this application is reviewed, even if those conclusions would not have been apparent at the time this application is originally filed.
Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
The methods and techniques described herein may be performed on a processor based device. The processor based device will generally comprise a processor attached to one or more memory devices or other tools for persisting data. These memory devices will be operable to provide machine-readable instructions to the processors and to store data. Certain embodiments may include data acquired from remote servers. The processor may also be coupled to various input/output (I/O) devices for receiving input from a user or another system, or sensors, and for providing an output to a user or another system. These I/O devices may include human interaction devices such as keyboards, touch screens, displays and terminals as well as remote connected computer systems, modems, radio transmitters and handheld personal communication devices such as cellular phones, “smart phones”, digital assistants and the like.
The processing system may also include mass storage devices such as disk drives and flash memory modules as well as connections through I/O devices to servers or remote processors containing additional storage devices and peripherals.
Certain embodiments may employ multiple servers and data storage devices thus allowing for operation in a cloud or for operations drawing from multiple data sources. The inventor(s) contemplates that the methods disclosed herein will also operate over a network such as the Internet, and may be effectuated using combinations of several processing devices, memories and I/O. Moreover any device or system that operates to effectuate techniques according to the current disclosure may be considered a server for the purposes of this disclosure if the device or system operates to communicate all or a portion of the operations to another device.
The processing system may include communications devices such as a wireless transceiver. These wireless devices may include a processor, memory coupled to the processor, displays, keypads, WiFi, Bluetooth, GPS and other I/O functionality. Alternatively, the entire processing system may be self-contained on a single device in certain embodiments.
The methods and techniques described herein may be performed on a processor based device. The processor based device will generally comprise a processor attached to one or more memory devices or other tools for persisting data. These memory devices will be operable to provide machine-readable instructions to the processors and to store data, including data acquired from remote servers. The processor will also be coupled to various input/output (I/O) devices for receiving input from a user or another system and for providing an output to a user or another system. These I/O devices include human interaction devices such as keyboards, touchscreens, displays, as well as remote connected computer systems.
The thrustors are attached to controllers 12, 116, 118, and 122 for providing variable power to the thrustors under the control of an on-board flight processors 126. To effectuate power usage multiple power sources, such as batteries, 136 or solar convertors (not shown) may be employed. These power sources may operate independently powering different operations, operate in tandem, or provide power under the control of the on-board flight processor 126. While
The on-board flight processor 126 is coupled to memory, input-output (I/O) devices, and communications systems such as wireless radio, Bluetooth, GPS receiver, and the like. The wireless communications may include a link for controlling the flying vehicle from a remote operator or, in some embodiments the pre-planned flight may be stored in memory and used by the processor 126 to control flight.
Sensors 128, 130, 132, and 134 are coupled to the on-board flight processor 126. Depending on the nature of these sensors they may also be coupled to one or more of the controllers, the motors power supply, or other electro-mechanical assembly. The types and operation of the sensors may be pre-selected for specific flight characteristics. For example, and without limitation, sensors employed may include:
Navigation may be further effectuated using accelerometers and gyroscopes such as those conventionally available by ST Micro, Inc. These devices include 3-axis gyroscopes with sensing structure for motion measurement along all three orthogonal axes—other solutions on the market rely on two or three independent structures.
Conventionally available gyroscopes may be employed to measure angular velocity with a wide range to meet the requirements of different applications, ranging from dead reckoning to more precise navigation. ST's angular rate sensors are already used in mobile phones, tablets, 3D pointers, game consoles, digital cameras and many other devices.
Commercially available motion processing units may also be used to effectuate certain embodiments as disclosed here. For example, and without limitation, the MPU6000 family of devices by TDK, inc. which includes a 3-axis gyroscope and a 3-axis accelerometer on the same silicon die together with an onboard digital motion processor capable of processing complex 9-axis sensor fusion algorithms.
Sensors may provide for direct programming of a setpoint. In which case the sensor outputs a signal indicating the status. For example, it may only send a signal when the setpoint is reached. Other sensors may provide continual readings of condition, say vibration frequency. In those cases, a setpoint may be stored in memory for access by program control software.
Sensors information also includes position information of the flight control surfaces, including, but not limited to wing position information, flap position, aileron information and the like.
Further coupled to the power source and on-board flight processor 126 are wing surface controls 138 and wing position controls 140. The wing surface controls control operation of the wings, including, but not limited to, ailerons, flaps, spoilers, and other control surfaced used to operate the vehicle in flight. Since these surfaces are under control of the processor 126, they may be operated to perform a preprogrammed flight or in response to signals received through the communications subsystem. Conventional flight operations may be performed in conjunction with the vertical thrust subsystem 138 and the wing position control subsystem 140.
Also coupled to the processor 126 is a wing position control 140 which provides for a dynamic wing that has a moveable profile. The wings are hinged and coupled to an actuator that shifts the wings during operation. This effectuates a change in the angle of attack of the entire wing and may increase the lift or other operations. Moreover, a folding dynamic wing, when positioned to minimized drag, may save energy and allow for flight over large distances after a vertical take-off. Conventionally known as a variable-sweep wing, (or “swing wing”), the airplane wing, or set of wings, may be swept back and then returned to its original position during flight. The variable-sweep wing is most useful for those aircraft that are expected to function at both low and high speed, such as VTOLs.
Some embodiments may employ flight control technology and structural materials to tailor the aerodynamics and structure of aircraft, which may remove the need for variable sweep angle to achieve the required performance; instead, wings are given computer-controlled flaps on both leading and trailing edges that increase or decrease the camber or chord of the wing automatically to adjust to the flight regime.
The processor 126 may provide a user interface (not shown) to provide for an operator to operate the flying vehicle by sending control signals to the processor 126. In other embodiments the processor 126 may operate on predetermined control information stored in memory. Moreover, the processor 126 may provide operator assistance by combining user instructions with preprogrammed operations, for example, and without limitation, a sensor may detect a wing stall, and increase power to a vertical thrustor to provide lift compensation.
An exit nozzle 218 is configured to direct the output air flow from the blades 210 to exhaust. The exit nozzle 218, together with the input nozzle 214 operate collectively as a form of ‘de Laval” nozzle which is generally characterized as a tube that is pinched in the middle, making a carefully balanced, asymmetric hourglass shape. The pinched tube, by altering the volume of the airflow through the nozzle, also operates to alter the pressure of the airflow through the nozzle.
The thrust assemblies and the individual thrustors may be operated under control of a user or programmatically through instructions provided by a processor. Flight control, in some embodiments, may operate similar to a quadcopter because the thrust assemblies are positioned in the four corners of the airframe 310. Different numbers of thrust assemblies may be used in some embodiments.
References in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment described may include a particular feature, structure or characteristic, but every embodiment may not necessarily include the particular feature, structure or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one of ordinary skill in the art to effect such feature, structure or characteristic in connection with other embodiments whether or not explicitly described. Parts of the description are presented using terminology commonly employed by those of ordinary skill in the art to convey the substance of their work to others of ordinary skill in the art.
Included on the airframe 310 is a thrust assembly 322 positioned orthogonally to the thrust of the vertical thrust assemblies to provide horizontal thrust. The horizontal thrust assembly 322, shown from a rear perspective in the insert, allows for providing horizontal thrust. Horizontal thrust generated when the wing 320 is angled to provide lift during flight will allow operation as a “fixed wing” aircraft, reducing or eliminating reliance on vertical thrustors. Since fixed wing aircraft are more fuel efficient than rotating propellers, transitioning from vertical to horizontal thrusters may save energy and increase flying time for a given amount of fuel and power.
Certain embodiments as shown and described herein employ both vertical and horizontal thrusters as well as an adjustable wing. In operation, the three elements may operate together to effectuated a flight operation. For example, and without limitation, flight may begin using only vertical thrusters. Once at a certain altitude, say clear of trees or other obstacles, the horizontal thrustors may provide horizontal thrust as the wing is being positioned to provide lift at that velocity. When the horizontal velocity is sufficient, the vertical thrustors taper back and the weight of the flying vehicle will be supported at altitude by the wings, substantially using only horizontal thrust.
For landing, a similar operation may be employed in reverse wherein the vertical thrustors are engaged to provide lift as the wing is positioned to accommodate a restricted landing area. As the burden of light shifts to the vertical thrustors, then the horizontal thrustors will provide less thrust to allow for landing the flying vehicle.
In certain embodiments the wing may have different configurations. For example, and without limitation, the wings may be small and provide minimal lift. Moreover, if a wing is employed in that embodiment, it may not have moveable surfaces, relying instead on fixed positioned of the wing.
The wing 330 is illustrated as formed from several moveable parts, a tip section 332, a central section 334 and a frame section 336. The frame section 336 is affixed to the airframe at a hinge 338. The tip section 332 is coupled to the central section 334 using a moveable hinge. Operation of the hinge may be effectuated using a jackscrew mechanism (not shown) to position the relative angle of the tip section 332 to the central section 332. The jackscrew may be either electrically operated or hydraulically operated in certain embodiments. Moreover, control of the jackscrew mechanism may be through the use of an on-board processor allowing for automatic movement of the tip section 332 during flight. The automatic movement may include directions from a user to the processor, or pre-programmed operation of the tip section 332 through processor instructions and feedback from sensors. Operation of the hinge may require the ability to hold the relative position of the tip section 336 with the central section 334, however, in some embodiments, the entire weight of the aircraft does not rest on the wing because vertical thrustors may provide additional lift. Convention jackscrew and wing position controls are available for use in controlling flaps, ailerons and spoilers on wing control surfaces.
The central section 334 is coupled to the frame section 336 using a moveable hinge similar to the coupling the tip section 332 to the central section 334. A processor controlled jackscrew positions the relative angle between the central section 334 and the frame section 336 using conventional flight surface control equipment. Similarly, the jackscrew may be either electrically operated or hydraulically operated in certain embodiments. Moreover, control of the jackscrew mechanism may be through the use of an on-board processor allowing for automatic movement of the wing section during flight. The automatic movement may include directions from a user to the processor, or pre-programmed operation of the wing sections through processor instructions and feedback from sensors. Operation of the hinge may require the ability to hold the relative position of the sections, however, in some embodiments and implementations, the entire weight of the aircraft does not rest on the wing because vertical thrustors may provide additional lift.
The frame section 336 is coupled to the airframe using a processor control, multi-dimensional actuator that allows the wing to be swept back, raised up, or both during flight. Conventional multi-dimensional actuators such as a mechanically adjustable and controllable equilibrium position actuator (MACCEPA), and other are known in the art. In some embodiments the wings may be swept back providing little lift until a predetermined horizontal velocity is reached and as the wing is positioned for level flight, the wing is extended out from the airframe to allow the wing to operated and provide lift. Similarly the wing may be raised up as shown in
Certain embodiments may only use a portion (or none) of the wing as shown. For example, and without limitation, tip section 332, a central section 334 might not be employed, relying instead on the lift provided by the frame section 336.
The above illustration provides many different embodiments or embodiments for implementing different features of the invention. Specific embodiments of components and processes are described to help clarify the invention. These are, of course, merely embodiments and are not intended to limit the invention from that described in the claims.
Although the invention is illustrated and described herein as embodied in one or more specific examples, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention, as set forth in the following claims.
