WO2017189410A1

WO2017189410A1 - System and method for an unmanned aerial vehicle

Info

Publication number: WO2017189410A1
Application number: PCT/US2017/029082
Authority: WO
Inventors: Yordan Iskrev; Boris Iskrev
Original assignee: Uvionix Aerospace Corporation
Priority date: 2016-04-25
Filing date: 2017-04-24
Publication date: 2017-11-02
Also published as: EP3448756A4; EP3448756A1

Abstract

An unmanned aerial vehicle includes a tubular base structure, a motor having a stator, the stator being connected to the tubular base structure, an energy storage module configured to supply power to the motor, and at least one propeller driven by the motor, wherein the tubular base structure houses at least one cable for routing power or signals, or a fuel conduit or wire conduit.

Description

SYSTEM AND METHOD FOR AN UNMANNED AERIAL VEHICLE

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 62/ 327,014, filed on April 25, 2016, U.S. Provisional Application Serial No. 62/ 326,998, filed on April 25, 2016 and U.S. Provisional Application Serial No. 62/ 327,025, filed on April 25, 2016, all of which are hereby incorporated by reference herein in their entireties.

FIELD OF THE INVENTION

[0002] The present invention relates generally to aerial vehicles and, more particularly, to an unmanned aerial vehicle, a controller for an unmanned aerial vehicle and a system and method for controlling an unmanned aerial vehicle.

BACKGROUND OF THE INVENTION

[0003] An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot aboard. Its flight is controlled either autonomously by onboard computers or by the remote control of a pilot on the ground or in another vehicle. UAVs are commonly used in military and special operations applications, and are increasingly finding uses in civil, commercial and recreational applications, such as policing and surveillance, aerial filming, and delivering of packages to end consumers.

[0004] Existing UAVs may be of the single rotor or dual coaxial rotor type, which provide a number of distinctive advantages over other UAV designs. For example these types of UAVs typically have a compact footprint, a small rotor disc surface area, and a small circumference, which makes them particularly suitable for a number of application where close interaction with people and reliable operation even with environment disturbances is essential. [0005] One notable problem when designing single rotor or dual coaxial rotor UAVs is the inherent difficulty of the proper weight distribution throughout the UAV. Three important high-mass objects, the propulsion system (including the electric motor and propellers), the energy source module (typically a battery), and the cargo module (e.g., a cargo compartment, camera or other useful cargo/ instrument the UAV transports), must often be taken into account, which affect the weight distribution of the UAV.

[0006] As is also known in the art, UAV controllers are typically utilized for

interactively controlling the motion of the UAV. While generally suitable for what is regarded as ordinary performance, existing controllers are often cumbersome and difficult to handle. In particular, existing controllers are often heavy, have a center of mass that makes it difficult for an operator to handle the device, and/ or have poor viewing angles particularly when a user interacts with the controls.

[0007] In the course of a mission of an aircraft or unmanned aerial vehicle ("UAV" ), regardless of the application, it is often desirable to land the aircraft on a pre-specified location, such as on the ground or on a moving vehicle or platform, in order to ensure safety of the personnel and/ or property and/ or to match a specific requirement of the mission. In many cases, the pre-specified landing location is beyond, or out of, the line of sight of a remote operator of the UAV.

[0008] In view of the above, there is therefore a need for a UAV design in which the weight of the UAV is distributed in such a way as to minimize the inertial moment of the UAV. In view of the above, there is therefore also a need for a UAV controller that is ergonomic and which presents an optimal viewing angle, particularly when the controls are manipulated by an operator. Further, in view of the above, there is a need for a system and method for the automated landing of an aircraft of UAV in a variety of landing scenarios. SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide an unmanned aerial vehicle.

[0010] It is another object of the present invention to provide an unmanned aerial vehicle in which the weight of the UAV is distributed in such a way as to minimize the inertial moment of the UAV.

[0011] It is another object of the present invention to provide an unmanned aerial vehicle that provides a shorter path for signal and/ or power-carrying cables as compared to existing vehicles.

[0012] It is an object of the present invention to provide a controller for an unmanned aerial vehicle.

[0013] It is another object of the present invention to provide a controller for an unmanned aerial vehicle that is lightweight.

[0014] It is another object of the present invention to provide a controller for an unmanned aerial vehicle that is ergonomic.

[0015] It is another object of the present invention to provide a controller for an unmanned aerial vehicle that has an optimal center of mass.

[0016] It is another object of the present invention to provide a controller for an unmanned aerial vehicle that allows for convenient user interaction with the controls.

[0017] It is an object of the present invention to provide a system and method for the automated landing of an unmanned aerial vehicle. [0018] It is another object of the present invention to provide a system and method for the automated landing of an unmanned aerial vehicle in a variety of landing scenarios.

[0019] It is another object of the present invention to provide a system and method for the automated landing of an unmanned aerial vehicle in a beyond-line-of-sight (BLOS) flight operation.

[0020] It is another object of the present invention to provide a system and method for the automated landing of an unmanned aerial vehicle for delivering packages to end consumers.

[0021] These and other objects are achieved by the present invention.

[0022] According to an embodiment of the present invention an unmanned aerial vehicle includes a tubular base structure, a motor having a stator, the stator being connected to the tubular base structure, an energy storage module configured to supply power to the motor, and at least one propeller driven by the motor, wherein the tubular base structure houses at least one cable for routing power or signals, or a fuel conduit or wire conduit.

[0023] According to another embodiment of the present invention, a controller for an unmanned aerial vehicle includes a frame having a pair of opposed arms configured to removably receive a smart device therebetween, at least one point stick module positioned on at least one of the arms, and a control unit configured to establish and maintain a connection with the smart device. The at least one point stick module is operable by a user to control movement of the unmanned aerial vehicle.

[0024] According to yet another embodiment of the present invention, a method for the automated landing of an unmanned aerial vehicle includes controlling an unmanned aerial vehicle from a takeoff point to a point generally vertically above a landing area, capturing a photograph of the landing area from the unmanned aerial vehicle, transmitting the photograph to a first remote control device located near the landing area, prompting an observer to select a landing point on the photograph via the first remove control device, calculating a reference trajectory for a landing phase in dependence upon a location of the unmanned aerial vehicle in relation to the selected landing point, and controlling movement of the unmanned aerial vehicle to the landing point according to the calculated reference trajectory.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below:

[0026] FIG. 1 is a perspective view of a portion of an unmanned aerial vehicle according to an embodiment of the present invention.

[0027] FIG. 2 is a cross-sectional view of the unmanned aerial vehicle of FIG. 1.

[0028] FIG. 3 is a side elevational view of an unmanned aerial vehicle, according to another embodiment of the present invention.

[0029] FIG. 4 is a top plan view of the unmanned aerial vehicle of FIG. 3. [0030] FIG. 5 is a cross-sectional view of area A of FIG. 3.

[0031] FIG. 6 is side, cross-sectional view of the unmanned aerial vehicle of FIG. 3, shown with a battery compartment and cargo compartment attached to the vehicle.

[0032] FIG. 7 is a perspective view of a controller for an unmanned aerial vehicle, according to an embodiment of the present invention. [0033] FIG. 8 is a front elevational view of the controller of FIG. 7.

[0034] FIG. 9 is a top plan view of the controller of FIG. 7.

[0035] FIG. 10 is a left side elevational view of the controller of FIG. 7.

[0036] FIG. 11 is a rear elevational view of the controller of FIG. 7.

[0037] FIG. 12 is a perspective view of the controller of FIG. 7, shown coupled to a tablet.

[0038] FIG. 13 is a perspective view of a controller for an unmanned aerial vehicle, according to another embodiment of the present invention.

[0039] FIG. 14 is a front elevational view of the controller of FIG. 13.

[0040] FIG. 15 is a top plan view of the controller of FIG. 13.

[0041] FIG. 16 is a left side elevational view of the controller of FIG. 13.

[0042] FIG. 17 is a rear elevational view of the controller of FIG. 13.

[0043] FIG. 18 is a perspective view of the controller of FIG. 13, shown coupled to a tablet.

[0044] FIG. 19 is a schematic illustration of a system for controlling an unmanned aerial vehicle utilizing the controller of FIG. 7, according to an embodiment of the invention.

[0045] FIG. 20 is a simplified, schematic illustration of a system for the automated landing of an unmanned aerial vehicle, according to an embodiment of the present invention. [0046] FIG. 21 is a perspective illustration of a first type of landmark used by the system of FIG. 20.

[0047] FIG. 22 is a perspective illustration of a LED based landmark used by the system of FIG. 20.

[0048] FIG. 23 is a perspective illustration of another type of landmark used by the system of FIG. 20.

[0049] FIG. 24 is a schematic illustration of the system of FIG. 20, showing the various stages of flight of an unmanned aerial vehicle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0050] With reference to FIGS. 1 and 2, an unmanned aerial vehicle ("UAV") 10 according to an embodiment of the present invention is illustrated. The UAV 10 may generally take the form of any UAV known in the art. As illustrated therein, the UAV is depicted as a dual coaxial rotor UAV. The UAV 10 includes a tubular base structure 12 operatively connected to a motor having a rotor 14 and a stator 16. As best illustrated in FIG. 2, the tubular base structure 12 is rigidly attached to the stator of the motor (or to the stators of both motors in the case of a dual coaxial rotor). In an embodiment, the stator(s) 16 and the tubular base structure 12 are integrated into a single structure.

[0051] The tubular base structure 12 preferably includes, or is otherwise connected to, an upper flange 18 and a lower flange 20 (or similar mounting fixtures), the purposes of which will be described hereinafter. The tubular base 12 also includes a rotor flange 22 connected to the rotor 14, which is utilized to attach propellers 24, 26 to the rotor 14 using bolts 28 or other suitable fasteners. The tubular base structure 12 is spatially mounted along the center of rotation of the propellers 24, 26 of the UAV. [0052] As also shown in FIG. 2, the unmanned aerial vehicle 10 includes a plurality of internal ball bearings 30 that facilitate rotation of the propellers 24, 26, and power cables 32 for connecting the motor coils to an electronic speed controller (not shown) for the motor.

[0053] Referring now to FIGS. 3-6, an unmanned aerial vehicle 100 according to another embodiment of the present invention is illustrated. The unmanned aerial vehicle 100 is substantially similar to the unmanned aerial vehicle 10 described above in connection with FIGS. 1 and 2, where like reference numerals designate like part.

[0054] FIG. 6 shows the UAV 100 with a hollow cargo compartment 110 having a lid 112 and a energy source module 114 attached to the tubular base structure 12 via the upper and lower flanges 18, 20, respectively. The lower flange 20 may also be utilized to connect auxiliary electronics to the UAV. The cargo compartment 110 may be utilized to contain packages or other cargo for delivery to end customers.

[0055] In either of the embodiments described above, the tubular base structure 12 is manufactured from a lightweight material with high rigidity. Suitable materials may include impregnated carbon fiber, aluminum, magnesium or injection molded polymers (with or without reinforcement fillers). In certain embodiments, the tubular base structure 12 may be manufactured with numerous openings for weight reduction and/ or cable routing purposes. Importantly, the tubular base structure 12 is generally hollow and defines a vertical pathway therethrough, and is therefore particularly suitable for use for running power cables to the rotor motors of the UAV, for running power cables from the battery to the motor electronic speed controller module and/ or other electronics, for routing signaling cables, and for various multi-purpose conduits. Moreover, the tubular base structure 12 serves as a base structure for the attachment of the energy source module 114, the cargo compartment 110 and control mechanisms.

[0056] Importantly, the configuration of the tubular base structure provides an as short as possible path to route the power cables from electronic speed control module(s) to the energy source module, and from the motor(s) to the electronic speed control module(s). It also provides an as short as possible path to route signal and/ or power carrying cables from the upper subsection of the UAV to the lower subsection of the UAV, in the cases where different electronic components, and/ or sensors and/ or actuators are distributed in both the lower and the upper subsections. For all power cables this improves the efficiency and reduces the voltage drop; for all signal cables, this improves signal to noise ratio by reducing the noise.

[0057] In yet other embodiments, it is contemplated that the interior of the tubular base structure 12 can be utilized for at least partially integrating or housing the energy source module of the UAV (e.g., a battery or fuel tank). Importantly, positioning the energy source module within the tubular base structure 12 mitigates the offsetting effect that a top-mounted or bottom-mounted energy source module typically has on the center of mass of the UAV.

[0058] Importantly, the ability to pass cables through the tubular base structure, and the ability to house the energy storage module (e.g., battery, fuel tank, fuel cell, etc.) within the hollow base structure provides a more optimal weight distribution than existing vehicles. In particular, by locating the center of mass more closely to the geometric center of the UAV, inertial moments of the UAV can be minimized to an extent heretofore not seen in the art.

[0059] In an embodiment, the present invention also provides a controller for an unmanned aerial vehicle, such as unmanned aerial vehicle 10 or 100, described above. With particular reference to FIGS. 7-12, a controller 200 for an unmanned aerial vehicle (e.g., unmanned aerial vehicle 10 or 100) is illustrated. While the present invention is described in reference to an unmanned aerial vehicle, it should be appreciated that the present invention may also be utilized to control other vehicles and machinery, more generally. [0060] As shown therein, the controller 200 includes a frame 212 having a pair of opposed arms 214, 216 configured to receive opposed top and bottom edges of a smartphone, tablet laptop computer or other electronic device 222, and a transverse arm 218 configured to receive a side edge of the smartphone or tablet. In an embodiment, the length of the arms 214, 216, 218 may be adjustable so as to accommodate various smartphones and/ or tablets that are different in size. In other embodiments, the frame 212 may be manufactured to specifically accommodate various specific models of smartphones, laptop computers and/ or tablets.

[0061] As further shown in FIGS. 7-12, the controller 200 further includes a pair of opposed pointing/ point stick modules 220 located on the distal ends of the arms 214, 216. As used herein, "pointing stick module" or "point stick module" means a joysticklike electro-mechanic module (typically used for computer-mouse alternatives / input human-interface device), of either one of the following types: (a) where two or more strain gauges are used to measure the force applied by a user and determine X and Y offset of the desired motion (e.g., Sprintek SK7102 pointing stick mouse encoder), or (b) where the user moves with his/her finger a tiny magnet and a hall-effect based integrated circuit is used to determine the X and Y displacement of the magnet (e.g., Austrian Micro Systems EasyPoint joystick and system), which are proportional to the desired motion X and Y offsets

[0062] As illustrated therein, and most clearly in FIG. 12, the pointing stick modules 2220 are positioned on or adjacent to the lateral sides of a smartphone/ tablet 220, when attached to the controller 200 in a way that the "stick" of at least one pointing stick module 220 is positioned below or close to the thumb of the user, when holding the smartphone / tablet in "landscape" or "portrait" orientation, in order the user to be capable of simultaneously holding the smartphone / tablet 222 and operating the pointing sticks. [0063] In the preferred embodiment, the plane of force application (left-right and front- back) of the pointing sticks is parallel or at an angle to the plane of the screen of the smartphone / tablet.

[0064] In an embodiment, the UAV controller 200 can be designed as a one solid device, in which case, every controller will be specially designed to fit a particular

brand/ model of smartphone/ tablet. In other embodiments, the controller can be designed as two solid pieces, joined by a flexible / adjustable link - in which case the controller can be used for a number of smartphones / tablets of varying sizes and configurations.

[0065] In an embodiment, the power supply for the controller 200 is provided either by a built-in battery (rechargeable or replaceable) or via wired or wireless energy transfer from the battery of the smartphone/ tablet.

[0066] In an embodiment, the point stick module 220 on the left arm 214 is configured to control the altitude / heading of the UAV with which the controller 200 is design to interface, while the point stick module on the right arm 216 is configured to control the attitude of the UAV. For example, in operation, when the user applies vertical upward force on the attitude control stick, this command will have the meaning of "nose down" change of the attitude of the UAV, with the setpoint angle of the attitude (with respect to a water level attitude) proportional to the intensity of the force exerted by the user on the point stick module. Alternatively, when the user applies vertical downward force on the attitude control stick this command will have the meaning of "nose up" change of the attitude of the UAV, with the setpoint angle of the attitude (with respect to a water level attitude) proportional to the intensity of the force exerted by the user on the point stick module. Moreover, when the user applies horizontal left force on the attitude control stick, this command will have the meaning of "bank left" change of the attitude of the UAV, with the setpoint angle of the attitude (with respect to a water level attitude) proportional to the intensity of the force exerted by the user on the point stick module. Conversely, when the user applies horizontal right force on the attitude control stick this command will have the meaning of "bank right" change of the attitude of the UAV, with the setpoint angle of the attitude (with respect to a water level attitude) proportional to the intensity of the force exerted by the user on the point stick module. In an embodiment, any combination of commands, e.g. left and up, or down and right, etc. will be supported. In an embodiment, a released attitude control stick will have the meaning of "water level attitude."

[0067] Further to the above, in operation, when the user applies vertical upward force on the altitude / heading control stick this command will have the meaning of "ascend" change of the altitude of the UAV, with the setpoint of the upward vertical velocity of the UAV proportional to the intensity of the force exerted by the user on the point stick module. When the user applies vertical downward force on the altitude / heading control stick this command will have the meaning of "descend" change of the altitude of the UAV, with the setpoint of the downward vertical velocity of the UAV

proportional to the intensity of the force exerted by the user on the point stick module. In an embodiment, zero vertical force applied on the stick will have the meaning of "hold current position". Moreover, when the user applies horizontal left force on the altitude / heading control stick this command will have the meaning of "yaw left" change of the heading of the UAV, with the setpoint yaw velocity proportional to the intensity of the force exerted by the user on the point stick module. Conversely, when the user applies horizontal right force on the altitude / heading control stick this command will have the meaning of "yaw right" change of the heading of the UAV, with the setpoint yaw velocity proportional to the intensity of the force exerted by the user on the point stick module. Zero horizontal force applied on the stick will have the meaning of "hold current heading". Any combination of commands, e.g. left and up, or down and right, etc. will be supported.

[0068] In some embodiments, the UAV controller 200 may contain additional user interface modules or devices. For example, as illustrated in FIGS. 7-12, in an

embodiment, the controller 10 may include a plurality of light emitting diodes, including a first LED 224 and a second LED 226 positioned above the left point stick module 220, and a third LED 228 and a fourth LED 230 positioned above the right point stick module 2220. In an embodiment, the first LED 224 indicates the connection status of the controller device 200 to the smart device 222, the second LED 226 indicates the connection status of the UAV to the smart device 222 via WiFi/ LTE/4G/3G/ 2G/ GPRS, etc., the third LED 228 indicates the connection status of the UAV to the smart device 222 via Bluetooth Low Energy, and the fourth LED 230 indicates the health status of the UAV. Other configurations or layouts are also possible without departing from the broader aspects of the present invention.

[0069] As best illustrated in FIG. 8, buttons, including first and second buttons 232, 234 may also be positioned above the left point stick module 220. In an embodiment, the first button 232, when depressed while the UAV is in the air, will issue the command "Execute automated Landing" and when depressed while the UAV is landed will issue the command "Execute automated Take off." The second button 234, when depressed, will issue the command "Return to Takeoff point."

[0070] As shown in FIGS. 9-11, in an embodiment, the controller 200 may further include a switch 236 positioned on the rear side of the left arm. The switch is

configured to activate / deactivate the control of the UAV by the two point stick modules 220. When activated, the controller 10 continuously streams commands issued by the user via the two point stick modules 220. When not activated, a user's forces applied to the point stick modules 220 will not be forwarded to the UAV.

[0071] In connection with the above, the UAV controller 200 is configured to

communicate with a specially designed mobile application installed on the smartphone or tablet 222 by means of Bluetooth Classic/ Bluetooth Low Energy or other wireless connection protocol, or a wired connection to a port of the smartphone/ tablet. In an embodiment, the Bluetooth Low Energy communication module contains a CPU and a built-in transceiver, for example, of the type PSoC 4XXX, marketed by Cypress

Semiconductor. In an embodiment, the software application is configured to connect and maintain a data connection between the UAV and the tablet / smart device 222 using WiFi and/ or the cellular data link of the smart device 222, to connect and maintain a Bluetooth Low Energy connection between the smart device 222 and the controller device 10, to forward commands received from the controller device buttons/ switches / point sticks to the UAV for execution, and to update the status LEDs of the controller device 10 upon change of the monitored parameters. In addition to the above, firmware, running on the CPU/MPU of the controller device 10 continuously scan the buttons / switches / point sticks for changes, connects and maintains a Bluetooth Low Energy connection to the smart device 222, sends any changed states of the buttons / switches / point sticks to the smart device 222, and receives from the smart device updates on the status LEDs and change the state of the LEDs accordingly.

[0072] In some embodiments, the UAV controller 200 may or may not contain additional user interface modules or devices, for example, LEDs, buttons / switches, small screens and the like. In certain embodiments, the UAV controller 200 may also include additional modules such as, for example, a battery for enhancing the battery life of the smartphone / tablet, an amplified wireless / cellular link to communicate with the UAV directly, and/ or position/ altitude sensors (e.g., IMU, GPS).

[0073] In the preferred embodiment, as alluded to above, the UAV controller 200 contains a CPU module 240 and embedded software, with wireless communication capabilities - which is at least capable of: reading and interpreting the pointing stick module measurements, reading/ managing other UI modules on the UAV controller 200, and communicating with the smartphone / tablet 222 to which it is attached.

[0074] Turning now to FIGS. 13-18, a UAV controller 300 according to another embodiment of the present invention is shown. The controller is substantially similar to the controller 200 described above in connection with FIGS. 7-12, where like reference numerals designate like part. The controller 300 contains the same internal components as controller 200, and is configured to operate in a substantially similar manner to provide the same functionality. Rather than having a third support arm, however, the controller 300 only has a pair of opposed arms 214, 216 configured to receive the opposed top and bottom edges of a smartphone or tablet therebetween.

[0075] As also shown therein, the controller 300 includes opposed finger grip portions 302, 304 below the opposed arms 214, 216. These finger grip portions 302, 304 provide an ergonomic feel to the controller 300 for a user, and ensures that the user is able to securely and comfortably hold the controller while manipulating the point stick modules 220 and any other controls.

[0076] Importantly, the controllers disclosed herein are lightweight, ergonomic and present an optimal viewing angle for a user, particularly when the controls are manipulated.

[0077] Turning finally to FIG. 19, a system 400 for controlling an unmanned aerial vehicle is shown. The system includes the controller hereinbefore described, e.g., controller 20 or 300, a coupled smart device 222, and an unmanned aerial vehicle 410. As described above, the controller 200 is configured to physically receive the smart device 222 in a manner such that the smart device 222 is attached to the controller 200. In this state, a user or operator can economically grip the controller 200 and smart device 222 while simultaneously viewing the display screen of the smart device 222.

[0078] As discussed above, once the switch 236 is actuated, the controller 10 is operable to control movement of the unmanned aerial vehicle 210 through actuation of the respective point stick modules/ devices 220. In particular, in operation, a software application running on the smart device 222 is configured to connect and maintain a first data connection between the UAV 410 and the smart device 222 using, for example, WiFi and/ or the cellular data link of the smart device 222, and to connect and maintain a second data connection (e.g., a Bluetooth Low Energy connection) between the smart device 222 and the controller 200. When an operator manipulates the point stick devices 220 and/ or buttons 232, 234, these actions are translated into commands that are then sent to the smart device 222 over the second data connection. The smart device 222 then controls the UAV 410 in dependence upon the received commands, according to a control algorithm stored in memory and/ or according to a software application running on the smart device 222.

[0079] While the controller of the present invention has been described above in connection with unmanned aerial vehicles, it is contemplated that the controlled may be utilized to control other devices and machinery, more generally. In addition, in certain embodiments, the controller of the present invention may be utilized in conjunction with video games and the like, such as games on any electronic device with which the controller can be paired, including smartphones, tablets and laptops.

[0080] According to yet another embodiment of the present invention, a system and method for the automated landing of an unmanned aerial vehicle, which can be carried out utilizing the unmanned aerial vehicle and / or the controller hereinbefore described, is provided. In connection with this particular embodiment of the invention, the following terms are utilized:

Onboard - descriptor of a module or an equipment attached to the UAV while in flight.

Takeoff point - the point in space at which the UAV is positioned by its operator before it lifts off in the air.

Landing point - the point in space at which the observer desires the UAV to touch the ground (or the moving platform) during landing.

Landing area - the area of at least approximately 30 feet immediately around the landing point. The dimensions of the landing are defined by the UAV operator in a way to ensure safety of people, animals and property during landing of the UAV.

Liftoff/Takeoff Switch Point - the point in space, vertically above the takeoff point, at the maximum altitude that an onboard ground (or platform) ranging module is able to measure (SONAR, RADAR, LIDAR, etc), if such ranging module is used. If a ranging module is not used, the Liftoff and Takeoff will be one and the same flight stage. The Stage of Flight changes from Liftoff to Takeoff at the Liftoff /Takeoff Switch Point.

Takeoff/Cruising Switch Point -the point in space, vertically above the takeoff point at the cruising altitude, as defined by the UAV operator. The stage of flight changes from takeoff to cruising at the takeoff / cruising switch point.

Cruising/Landing Switch Point - the point in space, vertically above the landing point, at the cruising altitude, as defined by the UAV operator. The stage of flight changes from cruising to landing at the cruising/ landing switch point.

Landing/Touchdown Switch Point -the point in space, vertically above the landing point, at the maximum altitude that an onboard ground (or platform) ranging module is able to measure (SONAR, RADAR, LIDAR, etc), if such ranging module is used. If a ranging module is not used, the landing and touchdown will be one and the same flight stage.

[0081] For the purposes of describing the present invention the following definitions of the different stages of the flight are utilized herein:

Liftoff - the predominantly vertical flight path from the takeoff point to the liftoff/ takeoff switch point.

Takeoff - the predominantly vertical flight path from the liftoff/ takeoff switch point to the takeoff / cruising switch point.

Cruising - the predominantly horizontal flight path (linear direct route or via a number of waypoints) from the takeoff/ cruising switch point to the cruising/ landing switch point.

Landing - the predominantly vertical flight path from the cruising/ landing switch point to the landing/ touchdown switch point.

Touchdown - the predominantly vertical flight path from the

landing/ touchdown switch point to the landing point.

[0082] With reference to FIG. 20, according to an embodiment of the present invention, a system 500 for the automated landing of an unmanned aerial vehicle is provided. As indicated above, the system may be implemented utilizing the unmanned aerial vehicle and the controller(s) hereinbefore described. The system 500 includes an unmanned aerial vehicle, such as UAV 512, a first remote control system 514 residing at a remote location 15 (such as with a pilot 516), and a second remote control system 518 residing at a landing area (such as with an observer 520). The landing area 522 may include a landmark 524 and a landing point 526.

[0083] The unmanned aerial vehicle 512 is preferably an unmanned vertical takeoff and landing aircraft (VTOL) and is equipped with a control module having one or more hardware processors / microcontrollers, all operating separately or interconnected, running a collection of embedded computer software, including the a landing algorithm, as discussed in detail below. A notable software component, needed for but not part of this invention, is the availability of a reference trajectory following algorithm running in the control module. This algorithm ensures that once preset with a reference trajectory, it will calculate the necessary attitude angles and level of thrust of the UAV 512, such that the reference trajectory is closely followed.

[0084] The UAV 512 further includes one or more electromagnetic wave detectors 528. The electromagnetic wave detectors 528 may be, for example, a visual or multispectral camera or detector, used to search for and track the position of a landmark, e.g., landmark 524 relative to the camera/ detector 528. Data from the electromagnetic wave detectors 528 is preferably interfaced to and processed by the control module of the UAV 512. Pictures (diagrams) and/ or video from electromagnetic wave detectors 528 can be transmitted to an observer, e.g., observer 520, and to the pilot, e.g., pilot 516, at appropriate points of time, e.g., over a wireless communication link 530, as described in detail below.

[0085] In an embodiment, the electromagnetic wave detectors 528 may be equipped with a wavelength filter, in order to increase the signal-to-noise (SNR) ratio of the measured signal and thus facilitate more robust and resilient detection and tracking of the landmark 524. The electromagnetic wave detectors 528 may or may not be attached to an optical image stabilization device, known as "gimbal", which apart from decreasing the noise in the observed signal, may offer capabilities to alter the

orientation of the electromagnetic wave detectors 528 relative to the UAV 512, thus enabling the electromagnetic wave detectors 528 to observe a broader area, without changing the attitude of the UAV 512.

[0086] The UAV 512 further includes communication equipment or modules capable of establishing bi-directional data exchange between the UAV 512 and the observer's remote control equipment 518 and the pilot's remote control equipment 514. Examples of the technical communication systems in such modules include, but are not limited to Bluetooth LTE or Classic, WiFi, GPRS, 2/3/4G, and LTE modules.

[0087] As used herein, the landmark 524 for the UAV 512 referred to above is an identifiable object (or pattern), positioned (or located) on the ground or attached to a moving vehicle / platform, such that the presence and relative position of the landmark 524 can be detected by the electromagnetic wave detector(s) 528 of the UAV 512. The landmark 524 denotes the exact position of the landing point 526, as specified by the observer 520. In an embodiment, the landmark 524 can include unique identification features, enabling the UAV 512 to distinguish it from other landmarks. In certain embodiments, the landmark 524 may include communication features, such that it can communicate with the UAV 512. The landmark 524 need not be a purposely positioned object, but could also be a pre-existing feature of the landing area 522 of the ground (or moving platform), such that the landing algorithm can identify it during an

identification phase of the landing algorithm, and distinguish it from the other features of the environment during landing.

[0088] In various embodiments, the landmark may include a rectangular board 532 having a polymer foil containing high-contrast pre-printed images, as shown in FIG. 21. The high-contrast pre-printed images may be completely or partly 2D barcodes. The pre-printed images may include identification information 534, either encoded in the 2D barcode or in clear text. In other embodiments, the landmark may include a light- emitting-diode (LED) equipped device 536, shown in FIG. 22, emitting light pulses (according to a pre-agreed communication protocol, known both by the landmark and the UAV 512), such that the UAV 512 can receive the data stream transmitted by the landmark. Importantly, this serves dual purposes: it facilitates the landing algorithm to distinguish the landmark from the surrounding environment and establish its relative position to the UAV 512, and encodes unique identification information of the landmark platform. In an embodiment, the landmark may include an electromagnetic wave emitter configured to emit electromagnetic waves for detection by the

electromagnetic wave detector 528 on-board the UAV 512. In yet other embodiments, the landmark may be a collection of natural and / or artificial features of the terrain 538, which are suitable for machine recognition/ fingerprinting, as shown in FIG. 23.

[0089] As alluded to above, the system 500 of the present invention may include remote control equipment 518 adjacent to the landing area 522 that is controllable by an observer 520. The observer 520 is there to directly observe the motion of the UAV 512 during landing and touchdown. In an embodiment, the observer 520 operates a system/ equipment 518 for remote operational control over the motion of the UAV 512. In a UAV delivery scenario, the observer 520 could be the final consumer, customer or recipient of a package carried by the UAV 512. It is contemplated that the observer 520 is present to ensure the safety of the landing location 522 which includes ensuring no people, animals or property are positioned, and there is no risk to become positioned during landing, near the landing point 526, and ensuring that the landing point 526 lies on a flat and horizontal surface, either stationary with respect to ground or moving with a constant speed (if the landing point is defined on a moving vehicle), has a sufficient area and unobstructed passage to and view of the sky and conforms to any other requirements the pilot or the operator may have. The observer 520 is also present to select the landing point 526 and physically position the landmark 524 over the landing point 526 (if the landmark is an object), to pinpoint the position of the landmark 524 on the observer's remote control equipment 518 at the appropriate point of time, to observe the physical descent of the UAV 512 during the landing and touchdown flight stages and, in case an emergency/ dangerous situation appears during landing/ touchdown, to actuate an emergency function of the observer's remote control equipment 518 to signal the UAV's control module to stop (and reverse) the motion of the UAV 512.

[0090] The observer's remote control system/ equipment 518 may be implemented as either a standalone electronic device or as a software application, operating on a smart device, such as a smartphone or a tablet, providing a user interface, and a number of functional capabilities. These capabilities include an emergency function that can be initiated to halt and optionally reverse the motion of the UAV 512, and a landmark selection function that is operable to specify the exact location of the landing

point / landmark 526 and transmit this location to the control module of the UAV 512 for use by the landing control algorithm. In addition, the remote control equipment 518 is configured to receive and display to the observer 520 an aerial view of the landing area 522 as photographed by the onboard electromagnetic wave detectors 528 of the UAV 512. In an embodiment, the observer 520 may be the same person as, or different from, the pilot 516.

[0091] As referred to herein, the pilot 516 is a person providing clearance and

monitoring the landing of the UAV 512. The primary functions of the pilot 516 are to monitor the descent of the UAV 512 during landing and touchdown, to check the correct initial detection of the landmark 524 (identification phase) by the landing algorithm, visually observe a remote transmitted image of the landing area 524 for potentially dangerous objects or circumstances, which may potentially cause damage to persons or property, approve or authorize the start of the landing stage of the flight at the cruising/ landing switch point, and monitor the correct tracking of the landmark 524 by the UAV control module and landing algorithm during landing and touchdown. In addition, the pilot 516 is present to, in case an emergency / dangerous situation appearing during landing/ touchdown, use the emergency function of the pilot's remote control equipment 514 to signal the UAV's control module to stop (and reverse) the motion of the UAV. [0092] In an embodiment, the pilot 516 may or may not be the same person as the observer 520, and will typically reside at a remote location 515. Depending on the requirements of the operator, the pilot 516 may need to have obtained an appropriate qualification. As alluded to above, the pilot 516 is equipped with a remote control system/ equipment 514 that can be implemented as either a standalone electronic device or as a software application, operating on a CPU containing device, such as a computer, smartphone or tablet, providing a user interface, and a number of control capabilities to the pilot 516. These include stopping and optionally reversing the motion of the UAV 512, restarting the landing process, and receiving and showing to the pilot an aerial view of the landing area 522 as photographed by the onboard electromagnetic wave detectors 528 of the UAV 512 (which can be a motion video or a still image). The pilot remote control equipment 514 may include a landmark selection function, which is used to specify the exact location of the landing point/ landmark 522 and transmit it to the control module of the UAV 512 for use by the algorithm. This can be utilized in case the observer 520 has difficulties selecting the landmark on his / her own. The pilot remote control equipment 514 also includes a landmark selection alteration function which, in case the pilot 516 decides that an inappropriate landing point/ landmark 526 is selected by the observer 520, can be used to select another landing point.

[0093] As also noted above, the landing algorithm used by the control module of the UAV 512 is an onboard software component, which is responsible for controlling the UAV 512 during an identification phase, a landing trajectory planning phase, and a tracking and positioning phase. The identification phase includes the initial detection of the landmark 524 based on the pinpointed location of the landmark 524 on the aerial photograph, and detecting the landmark's existence and relative position to the UAV 512. During the landing trajectory planning phase, depending on the relative position of the aircraft to the landmark and the desired landing strategy, the landing algorithm calculates a reference/ planned landing trajectory for the landing and touchdown stages of flight, which should be followed by the aircraft to reach the position of the landing platform. In an embodiment, the trajectory may be calculated in a number of ways, for example, horizontal positioning of the UAV 512 directly above the landmark and then vertical motion until touchdown. This system is advantageous to minimally disrupt the motion of other nearby UAVs and is appropriate when landing on the ground with minimum environmental disturbances (e.g., wind). It can also use a straight-line trajectory which is generated between the cruising/ landing switch point and the position of the landmark 524. This type of trajectory has advantages in cases of landing on a moving vehicle and in case of high level of environmental disturbances, since the trajectory is easier to recalculate. In an embodiment, the planned landing trajectory may be recalculated multiple times during landing, in the case where the actual motion of the UAV 512 significantly deviates from the trajectory.

[0094] During the tracking and positioning phase, once the initial detection of the landmark is confirmed, relative to the aircraft, and the landing stage of the flight has been initiated, the landing algorithm continuously re-detects the relative positions of the landmark 524 in reference to the UAV 512 and compares it to the planned landing trajectory. When any deviation from the actual motion to the planned/ reference trajectory are found, the landing algorithm sends a control corrective action to the UAV motion/ position/ attitude control algorithms to alter the motion of the UAV 512, such that the planned landing trajectory is followed.

[0095] Finally, an operator may oversee the entire system, and who may be the person or company responsible for the overall UAV flight mission, and is responsible for determining safety and operational flight parameters.

[0096] With reference to FIG. 24, in operation, the UAV 512 may be controlled, via the control module under direction from the pilot 516, from the takeoff point 600, to the liftoff/ takeoff switching point 602, to the takeoff / cruising switching point 604, and to the cruising/ landing switching point 106 via one or more waypoints 608, 610. In the preferred embodiment, however, control of the UAV 512 from the takeoff point to the cruising/ landing switching point may be completely autonomous. The UAV 512 is then controlled from the cruising/ landing switching point 106, to the

landing/ touchdown switching point 612, and ultimately to the landmark 614. [0097] Once the UAV 512 has arrived at the cruising/ landing switching point 606, i.e., horizontally near the landing point and the position of the observer, landing may be commenced. During this process, the electromagnetic wave detector(s) 528 on board the UAV 512 capture and send through its electrical interface to the control module a still aerial photo of the landing area. The UAV control module transmits via its wireless connection to the observer's remote control equipment 518 the still photo. The observer's remote control equipment 518, through its user interface (UI), displays to the observer 520 the received photo and alerts (sound and/ or visual alert) the observer 520 to select the landing point/ landmark 526. The observer 520, after following the operator's procedure, checks the safety of the area and the availability of a sufficiently unobstructed path to the sky from the landmark 524, selects using the observer's remote control equipment UI the location of the landmark/ landing point 526 by selecting a point on the photo. The observer's remote control equipment 518 the transmits the selected point, as Cartesian X and Y coordinates relative to the upper left corner of the photo, to the control module of the UAV 512.

[0098] The control module runs the identification phase of the landing algorithm in order to determine, if the landmark 524 is an object at the landing point 526, whether it can recognize a valid landing object, as per the set of requirements set forth by the operator for identifying a valid landmark and, if the landmark is a pre-existing feature on the ground, whether the landing algorithm's identification phase procedures can identify unique enough features of the landing point / landing area, which can be used for tracking the relative position of the UAV 512 to the landing point/ landmark during the descent. (Whether the landmark should be an object or a pre-existing feature of the landing area, is to be set forth by the operator in advance.)

[0099] If the result of the identification phase is positive, i.e. the landing algorithm was able to find a valid landmark 524 at the landing point, the control module of the UAV 512 transmits via its wireless connection to the pilot's remote control equipment 514 the same photo, together with the received X and Y coordinates of the selected landing point / landmark and information, showing that the landmark 524 has been successfully identified. If the result of the identification phase is negative, i.e. the landing algorithm was unable to find a valid landmark, the control module notifies the observer's remote control equipment 518 to ask the observer 520 for a new landing Point / landmark.

Upon confirmation by the observer 520, the electromagnetic wave detector(s) 528 (via the control module) sends another photo of selection and identification repeats, the necessary number of times, until a valid landmark has been identified.

[00100] The pilot's remote control equipment 514, through its UI, displays to the pilot 516 the received photo and the selected landing point/ landmark and alerts (sound and/ or visual alert) the pilot to check the area and confirm the landing. The pilot 516 then examines the photo following the operator's procedure, and after ensuring there are no people, animals or objects possibly endangering the landing operation, using the UI of the pilot's remote control equipment 514 clears the landing commencement. The pilot's remote control equipment 514 transmits via its wireless connection to the UAV control module the clearance for commencement of the landing. If, for any reason, the pilot 516 deems the landing unsafe he/ she may request the observer 520 to select another landing point/ landmark (in this case the pilot's remote control equipment 514 transmits to the control module a request for repeating of the selection of the landmark and the control module transmits to the observer's remote control equipment 518, this request, together with a new photo of the landing area) or deny the landing altogether. If the landing clearance is received the landing algorithm switches to the landing trajectory planning phase and calculates the reference trajectory for descending.

[00101] After the reference trajectory has been calculated, the landing algorithm presents this trajectory to the trajectory following algorithm of the control module. The landing algorithm switches to the tracking and positioning Phase. During this phase the landing algorithm continuously re-identifies the relative position of the landmark 524 to the UAV 512, compares it to the reference trajectory and continuously feeds to the trajectory following algorithm the error between the expected and actual position of the UAV 512, in order for the trajectory following algorithm to take corrective action. In an embodiment, the tracking and positioning phase of the landing algorithm runs continuously through the landing and touchdown stages of the flight. During this process, the control module, in parallel to running the above algorithms, continuously transmits a live-streamed video from the electromagnetic wave detectors 528 of the UAV 512 to the pilot's remote control equipment 514 (the latter continuously displays this to the pilot), monitors for corrective actions, initiated from the pilot 516 through the UI of the pilot's remote control equipment 514 and wirelessly transmitted to the control module, which executes them if such are received, monitors for corrective actions, initiated from the observer through the UI of the observer's remote control equipment 518 and wirelessly transmitted to the control module, which executes them if such are received.

[00102] As indicated above, an embodiment of the present invention relates specifically to landing of an unmanned aerial vehicle. In the preferred embodiment, neither the pilot 516 nor the observer 520, or the respective control modules/ control devices participate in takeoff and/ or cruising, although such control from takeoff to the cruising/ landing switching point is possible.

[00103] Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of this disclosure.

Claims

WHAT IS CLAIMED IS:

1. An unmanned aerial vehicle, comprising:

a tubular base structure;

a motor having a stator, the stator being connected to the tubular base structure; an energy storage module configured to supply at least one of power or fuel to the motor; and

at least one propeller driven by the motor;

wherein the tubular base structure defines a generally hollow passageway and houses at least one cable for routing power or signals, or a fuel conduit or wire conduit.

2. The unmanned aerial vehicle of claim 1, wherein:

the tubular base structure includes an upper fixture and a lower fixture.

3. The unmanned aerial vehicle of claim 2, wherein:

the upper fixture is configured to receive a cargo compartment for mounting the cargo compartment to the tubular base structure.

4. The unmanned aerial vehicle of claim 3, wherein:

the lower fixture is configured to receive an energy storage module for mounting the energy storage module to the tubular base structure opposite the cargo

compartment.

5. The unmanned aerial vehicle of claim 1, wherein:

the tubular base structure houses at least a portion of the energy storage module.

6. The unmanned aerial vehicle of claim 5, wherein:

the energy storage module is positioned in the tubular base structure such that the center of mass of the unmanned aerial vehicle and the geometric center of the unmanned aerial vehicle are approximately the same.

7. A controller for an unmanned aerial vehicle, comprising:

a frame having a pair of opposed arms configured to removably receive a smart device therebetween;

at least one point stick module positioned on at least one of the arms; and a control unit configured to establish and maintain a connection with the smart device; and

wherein the at least one point stick module is operable by a user to control movement of the unmanned aerial vehicle.

8. The controller of claim 7, wherein:

the at least one point stick module is a pair of point stick modules positioned on the opposed arms, respectively.

9. The controller of claim 7, further comprising:

a third arm configured to receive another edge the personal electronic device.

10. The controller of claim 7, wherein:

the smart device is one of a smartphone, a tablet and a laptop computer.

11. The controller of claim 7, wherein:

a distance between the pair of opposed arms is variable.

12. The controller of claim 7, further comprising:

at least one light emitting diode indicating at least one of a connection status of the controller to the smart device, a connection status of the unmanned aerial vehicle to the smart device, and a health status of the unmanned aerial vehicle.

13. The controller of claim 7, wherein:

the connection is a Bluetooth Low Energy connection.

14. The controller of claim 7, wherein:

the frame includes a pair of opposed finger grip areas positioned below the opposed arms, respectively.

15. A method for the automated landing of an unmanned aerial vehicle, comprising the steps of:

controlling an unmanned aerial vehicle from a takeoff point to a point generally vertically above a landing area;

capturing a photograph of the landing area from the unmanned aerial vehicle; transmitting the photograph to a first remote control device located near the landing area;

prompting an observer to select a landing point on the photograph via the first remove control device;

calculating a reference trajectory for a landing phase in dependence upon a location of the unmanned aerial vehicle in relation to the selected landing point; and controlling movement of the unmanned aerial vehicle to the landing point according to the calculated reference trajectory.

16. The method according to claim 15, further comprising the step of:

with a control unit on-board the unmanned aerial vehicle, assessing the sufficiency of the selected landing point to function as a tracking feature during the landing phase.

17. The method according to claim 16, further comprising the steps of:

transmitting the photograph with the selected landing point to a second remote control device located remote from the landing area; and

requesting clearance from an operator of the second remote control device to proceed with the step of calculating the reference trajectory and initiating the landing phase.

18. The method according to claim 17, further comprising the steps of: if clearance is received from the operator, automatically calculating the reference trajectory and initiating the landing phase; and

if clearance is not received from the operator, generating a prompt on the first remote control device to select a new landing point.

19. The method according to claim 17, further comprising the step of:

continuously transmitting a live-stream video of the landing point from the unmanned aerial vehicle to the second remote control device.

20. The method according to claim 17, further comprising the step of:

from one of the first remote control device and the second remote control device, initiating an emergency function whereby the landing phase of the unmanned aerial vehicle is interrupted.