[go: up one dir, main page]

WO2024246895A1 - Véhicule aérien - Google Patents

Véhicule aérien Download PDF

Info

Publication number
WO2024246895A1
WO2024246895A1 PCT/IL2024/050522 IL2024050522W WO2024246895A1 WO 2024246895 A1 WO2024246895 A1 WO 2024246895A1 IL 2024050522 W IL2024050522 W IL 2024050522W WO 2024246895 A1 WO2024246895 A1 WO 2024246895A1
Authority
WO
WIPO (PCT)
Prior art keywords
air vehicle
thrust
propulsion
wing
roll axis
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/IL2024/050522
Other languages
English (en)
Inventor
Meir MERGI
Ronen Barsky
Yogev KAT
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Israel Aerospace Industries Ltd
Original Assignee
Israel Aerospace Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Israel Aerospace Industries Ltd filed Critical Israel Aerospace Industries Ltd
Publication of WO2024246895A1 publication Critical patent/WO2024246895A1/fr
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00—Type of UAV
    • B64U10/20—Vertical take-off and landing [VTOL] aircraft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C15/00—Attitude, flight direction, or altitude control by jet reaction
    • B64C15/02—Attitude, flight direction, or altitude control by jet reaction the jets being propulsion jets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C29/00—Aircraft capable of landing or taking-off vertically, e.g. vertical take-off and landing [VTOL] aircraft
    • B64C29/02—Aircraft capable of landing or taking-off vertically, e.g. vertical take-off and landing [VTOL] aircraft having its flight directional axis vertical when grounded
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C39/00—Aircraft not otherwise provided for
    • B64C39/08—Aircraft not otherwise provided for having multiple wings
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/30—Aircraft characterised by electric power plants
    • B64D27/31—Aircraft characterised by electric power plants within, or attached to, wings
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00—Type of UAV
    • B64U10/25—Fixed-wing aircraft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U30/00—Means for producing lift; Empennages; Arrangements thereof
    • B64U30/20—Rotors; Rotor supports
    • B64U30/26—Ducted or shrouded rotors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00—Propulsion; Power supply
    • B64U50/10—Propulsion
    • B64U50/18—Thrust vectoring
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U70/00—Launching, take-off or landing arrangements
    • B64U70/10—Launching, take-off or landing arrangements for releasing or capturing UAVs by hand
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/30—Aircraft characterised by electric power plants
    • B64D27/33—Hybrid electric aircraft

Definitions

  • the presently disclosed subject matter relates to air vehicles, in particular to air vehicles capable of vectored thrust flight as well as aerodynamic flight.
  • CN 112407270 discloses a tail stock type vertical take-off and landing aircraft without control surface control.
  • the tail stock type vertical take-off and landing aircraft comprises a fuselage, and a nose, wings, wing tips, a power assembly and empennages which are mounted at the front part of the fuselage, wherein the nose is connected with the fuselage, the wings are connected to the middle section of the fuselage, the wing tips are installed at the ends of the wings and are conical, the power assembly comprises propellers connected with the wing tips and a driving device, and the empennages are located at the tail of the fuselage and distributed in a cross shape.
  • the aircraft disclosed by the invention has two flight modes, namely a multi-rotor flight mode and a fixed-wing flight mode, has the characteristics of a multi-rotor aircraft, can realize vertical take-off and landing and hovering, also has the characteristics of a fixed-wing aircraft, and can realize high-speed flight and economic cruise.
  • US 2005/178879 discloses a power- operated tail-sitting type mixed layout vertical take-off and landing aircraft.
  • the power- operated tail-sitting type mixed layout vertical take-off and landing aircraft is composed of a fuselage, airfoils, motors, propellers and landing gears; the fuselage axis coincides with the OX axis of a body axial system, the projections of the fuselage axis and the OX axis in an XOY plane of the body axial system are distributed in an X shape; each airfoil on the fuselage is divided into several sections, sweepback angles and dihedral angles of all the sections are different from one another, and excellent pneumatic performance and maneuvering performance are achieved through positively-curved airfoil profiles and negatively-curved airfoil profiles.
  • CN 106927040 discloses a tailstock type quad-rotor tailless configuration aircraft capable of taking off and landing perpendicularly.
  • the tailstock type quad-rotor tailless configuration aircraft capable of taking off and landing perpendicularly is composed of a fuselage, airfoils, vertical tails and power devices, wherein the airfoils are arranged on the two sides of the fuselage, the vertical tails are arranged on and below the tail portion of the fuselage correspondingly, and the center lines of the vertical tails on the upper portion and the lower portion and the axis of the fuselage are located in the same vertical plane.
  • the wingtip portions of the airfoils and the wingtip portions of the vertical tails are provided with the power devices, and a rotary shaft of each power device is parallel to the axis of the fuselage.
  • An auxiliary lifting wing is installed at the rear edge of each airfoil.
  • a rudder is installed at the rear edge of each vertical tail.
  • the wingtips of the airfoils and the wingtips of the vertical tails form four supporting points jointly, and by means of the four supporting points, the aircraft is docked on the ground in a vertically upward mode before the aircraft takes off and after the aircraft lands.
  • CN 108284950 discloses a four-ducted propeller powered fixed-wing unmanned aerial vehicle capable of achieving vertical takeoff and landing, and belongs to the field of unmanned aerial vehicles.
  • the four-ducted propeller powered fixed-wing unmanned aerial vehicle capable of achieving vertical takeoff and landing comprises a structural unit, power units and a flight control and avionic unit, wherein the structural unit comprises a fuselage, wings, control planes and tail supporting rods.
  • the fuselage is positioned at a central position of the whole unmanned aerial vehicle Four wings are fixed to the fuselage.
  • the adjacent wings of the four wings form included angles of 90 degrees.
  • the power units are arranged on the tips of the four wings; the control planes are arranged on the four wings.
  • the tail supporting rod is arranged on each wing.
  • Each power unit comprises four sets of ducted propellers.
  • a set of ducted propeller is arranged on each wing.
  • the flight control and avionic unit is mounted inside the inner cavity of the fuselage.
  • US 11,420,737 is directed to a high speed vertical takeoff and landing (VTOL) aircraft that includes fixed wing flight capabilities.
  • the high speed VTOL aircraft may include at least two thrust producing rotors located equidistant from a longitudinal axis of the aircraft on a main wing, and at least two thrust producing rotors located equidistant from a longitudinal axis of the aircraft on a vertical wing.
  • the aircraft can transition from a vertical flight configuration to a horizontal flight configuration and back.
  • US 9,567,075 discloses a multi-engine aircraft which is convertible from horizontal flight mode to a vertical flight mode.
  • the aircraft comprises an aircraft fuselage defining a fuselage longitudinal axis, and the first and second wing attached to the fuselage.
  • Each wing defines first and second wing segments.
  • the first segments are translatable about the fuselage longitudinal axis, from a horizontal mode position adjacent the second wing segments to vertical fight mode wherein the first wing segment are substantially offset from the second wing segments.
  • An aircraft propulsion unit is attached to each of the first and second wing segments.
  • the propulsion units attached to a common wing being disposed in substantial axial alignment when the aircraft operates in a horizontal flight mode, and being substantially offset when the aircraft operates in a vertical flight mode.
  • US 2020/0031458 discloses an aerial vehicle, such as an unmanned aerial vehicle, that includes a fuselage having a forward end, an aft end, and a duct extending between said forward end and said aft end, the duct being oriented along a longitudinal axis of said fuselage; a primary propulsion unit mounted within said duct and generating lift for upward and downward motion while said fuselage is in a substantially vertical orientation and thrust for forward motion while said fuselage is in a substantially horizontal orientation; a plurality of airfoils each having a proximal end attached at opposite sides of the fuselage, said airfoils providing lift during forward motion of said fuselage; and a plurality of secondary propulsion units generating thrust to tilt the fuselage between said substantially vertical orientation and said substantially horizontal orientation.
  • CN 106184738 discloses a detachable tailstock type vertical take-off and landing unmanned aerial vehicle.
  • Wings and a fuselage can be detachably assembled.
  • the wings and the fuselage can form two overall arrangement forms.
  • the X-shaped overall arrangement form two pairs of wings are mounted on the fuselage and are bilaterally symmetrical, and each pair of wings is of a longitudinal symmetry structure; and the included angle between the wings in each pair is 120 degrees, and the four wings form an X shape.
  • the Y-shaped overall arrangement form three wings are mounted on the fuselage, the included angel between every two adjacent wings is 120 degrees, and the three wings form a Y shape.
  • the unmanned aerial vehicle of the X-shaped overall arrangement form is suitable for long-distance flight under a wind-free condition.
  • CN 108639328 discloses a tailstock type axisymmetric multi-propeller vertical take-off and landing unmanned aerial vehicle.
  • the tailstock type axisymmetric multi-propeller vertical takeoff and landing unmanned aerial vehicle comprises an unmanned aerial vehicle body assembly, a head cover assembly, a tail cover assembly, power propeller assemblies and a symmetric wing assembly.
  • the tailstock type axisymmetric multi-propeller vertical take-off and landing unmanned aerial vehicle is characterized in that four wings are symmetrically arranged relative to an unmanned aerial vehicle body in a crossed shape; the power propeller assemblies are correspondingly contained on the four wings; landing gears with shock absorbing devices are used at the lower parts of the wings; in addition, the head cover assembly and the tail cover assembly are positioned at the two ends of the unmanned aerial vehicle body to reduce the air resistance in the cruise level flight process.
  • the attitude stabilization of the unmanned aerial vehicle is guaranteed; maneuvering actions, such as rolling and yawing, of the unmanned aerial vehicle are controlled by using trailing edge flaps and ailerons during horizontal flight.
  • CN 106240814 discloses a power-operated tail-sitting type mixed layout vertical take-off and landing aircraft.
  • the power-operated tail-sitting type mixed layout vertical take-off and landing aircraft is composed of a fuselage, airfoils, motors, propellers and landing gears; the fuselage axis coincides with the OX axis of a body axial system, the projections of the fuselage axis and the OX axis in an XOY plane of the body axial system are distributed in an X shape; each airfoil on the fuselage is divided into several sections, sweepback angles and dihedral angles of all the sections are different from one another, and excellent pneumatic performance and maneuvering performance are achieved through positively-curved airfoil profiles and negatively-curved airfoil profiles; four sets of propeller-motor power systems are installed on the four airfoils correspondingly, and the distances between the positions where the propeller-motor power systems are located and the OX axis
  • an air vehicle comprising: a fuselage defining a roll axis of the air vehicle; a fixed wing arrangement in fixed spatial disposition with respect to the fuselage; a propulsion system comprising at least four propulsion units, each one of said at least four propulsion units being mounted with respect to the wing system in lateral spaced relationship with respect to the roll axis, and wherein adjacent propulsion units are spaced circumferentially from one another about the roll axis; each said propulsion unit configured for generating a respective thrust along a respective thrust vector axis; wherein each respective thrust vector axis being in fixed inclined spatial orientation with respect to the roll axis such that the respective thrust has a nonzero thrust component defined on a plane orthogonal to the roll axis; and wherein the respective non-zero thrust component has a respective non-zero moment arm with respect to the roll axis such as to provide a respective roll moment about the roll axis.
  • respective said non-zero thrust component of each pair of circumferentially adjacent (i.e., circumferentially about the roll axis) said propulsion units are in mutually opposed rotational directions about the roll axis.
  • respective said non-zero thrust component of each pair of diametrically opposed said propulsion units with respect to the roll axis are in the same rotational direction about the roll axis.
  • respective said non-zero thrust component of one pair of diametrically opposed said propulsion units with respect to the roll axis are in a first rotational direction about the roll axis
  • respective said non-zero thrust component of another pair of diametrically opposed said propulsion units with respect to the roll axis are in a second rotational direction about the roll axis
  • said first rotational direction is an opposite rotational direction with respect to the second rotational direction
  • the thrust vectors of the propulsion units are non-parallel with respect to one another.
  • said propulsion system includes a port pair and a starboard pair of said propulsion units, and wherein for each one of said port pair and said starboard pair, the respective thrust vectors are converging in a forward direction towards a forward converging point when the air vehicle is viewed in side view.
  • said propulsion system includes a top pair and a bottom pair of said propulsion units, and wherein for each one of said top pair and said bottom pair, the respective thrust vectors are diverging in a forward direction away from an aft diverging point when the air vehicle is viewed in top view.
  • said propulsion system includes atop pair and a bottom pair of said propulsion units, and wherein for each one of said top pair and said bottom pair, the respective thrust vectors are converging in a forward direction towards a forward converging point when the air vehicle is viewed in top view.
  • said propulsion system includes a port pair and a starboard pair of said propulsion units, and wherein for each one of said port pair and said starboard pair, the respective thrust vectors are diverging in a forward direction away from an aft diverging point when the air vehicle is viewed in side view.
  • the respective moment arm from the non-zero thrust component to the roll axis is maximized.
  • each propulsion unit has a rotor axis.
  • the rotor axes of the propulsion units are non-parallel with respect to one another.
  • the respective rotor axis is co-axial with the respective thrust vector.
  • said propulsion system includes a port pair and a starboard pair of said propulsion units, and wherein for each one of said port pair and said starboard pair, the respective rotor axes are converging in a forward direction towards a forward converging point when the air vehicle is viewed in side view.
  • said propulsion system includes a top pair and a bottom pair of said propulsion units, and wherein for each one of said top pair and said bottom pair, the respective rotor axes are diverging in a forward direction away from an aft diverging point when the air vehicle is viewed in top view.
  • said propulsion system includes a top pair and a bottom pair of said propulsion units, and wherein for each one of said top pair and said bottom pair, the respective rotor axes are converging in a forward direction towards a forward converging point when the air vehicle is viewed in top view.
  • said propulsion system includes a port pair and a starboard pair of said propulsion units, and wherein for each one of said port pair and said starboard pair, the respective rotor axes are diverging in a forward direction away from an aft diverging point when the air vehicle is viewed in side view.
  • said propulsion system includes a first pair of diametrically opposed said propulsion units with respect to the roll axis, and a second pair of diametrically opposed said propulsion units with respect to the roll axis, wherein said propulsion units of the first pair are each configured to provide a roll control moment in a counter-clockwise direction, and wherein said propulsion units of the second pair are each configured to provide a roll control moment in a clockwise direction.
  • a starboard top said propulsion unit and a port bottom said propulsion unit are each configured to provide a roll control moment in a counter-clockwise direction
  • a starboard bottom said propulsion unit and a port top said propulsion unit are each configured to provide a roll control moment in a clockwise direction.
  • a starboard top said propulsion unit and a port bottom said propulsion unit are each configured to provide a roll control moment in a clockwise direction, and wherein a starboard bottom said propulsion unit and a port top said propulsion unit are each configured to provide a roll control moment in a counterclockwise direction.
  • said wing system comprises a plurality of wings laterally projecting from the fuselage.
  • said wing system comprises four wings in X-arrangement.
  • the wings are devoid of control surfaces for providing aerodynamically generated control moments in one or more of pitch roll and yaw.
  • the air vehicle comprises an empennage axially spaced by an axial spacing with respect to said wings.
  • said axial spacing is at least the size of a width of a human hand.
  • At least part of the fuselage has a diameter is such as to enable circumferentially to grasp the air vehicle via a human hand.
  • said human hand is of a 50 th percentile male.
  • an air vehicle comprising: a fuselage defining a roll axis of the air vehicle; four wings in X-arrangement with respect to the fuselage; four propulsion units, one propulsion unit being mounted with respect to each said wing in lateral spaced relationship with respect to the roll axis; each said propulsion unit configured for generating a respective thrust along a respective thrust vector axis; wherein each respective thrust vector axis being in fixed inclined spatial orientation with respect to the roll axis such that the respective thrust has a nonzero thrust component defined on a plane orthogonal to the roll axis; and wherein the respective non-zero thrust component has a respective non-zero moment arm with respect to the roll axis such as to provide a respective roll moment about the roll axis.
  • a control system to control operation of an air vehicle, wherein the air vehicle comprises a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, the control system comprising a processing unit and associated memory configured to generate one or more commands comprising: at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least roll during each one of said vectored thrust flight mode, aerodynamic flight mode, and transition mode.
  • an air vehicle comprising a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, and the control system as defined herein according to the second aspect of the presently disclosed subject matter.
  • a method of controlling an air vehicle comprising, by a processing unit and associated memory operatively coupled to the air vehicle: generating at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least roll during each one of said vectored thrust flight mode, aerodynamic flight mode, and transition mode.
  • a non-transitory storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform operations of controlling operation of an air vehicle
  • the air vehicle comprises a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis
  • the operations comprising, by the machine: generating at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least roll during each one of said vectored thrust flight mode, aerodynamic flight mode, and transition mode.
  • a control system to control operation of an air vehicle, wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, the control system comprising a processing unit and associated memory configured to generate one or more commands comprising: at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode from vectored thrust flight mode to aerodynamic flight mode; at least one modified first command operable to increase said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle at a desired level of matching.
  • said one or more commands further comprises at least one further modified first command operable to reduce said aggregate thrust generated by the propulsion system to cause summation of the vertical component of said aggregate thrust and an aerodynamic lift generated by the wings to match a weight of the air vehicle at said desired level of matching.
  • said level of matching is one of the following:
  • an air vehicle comprising a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, and the control system as defined herein according to the third aspect of the presently disclosed subject matter.
  • a method of controlling operation of an air vehicle wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, the method comprising, by a processing unit and associated memory operatively coupled to the air vehicle: generating at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode from vectored thrust flight mode to aerodynamic flight mode; generating at least one modified first command operable to increase said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle at a desired level of matching.
  • the method further comprises generating at least one further modified first command operable to reduce said aggregate thrust generated by the propulsion system to cause summation of the vertical component of said aggregate thrust and an aerodynamic lift generated by the wings to match a weight of the air vehicle at said desired level of matching.
  • said level of matching is one of the following: 100%, wherein the air vehicle is correspondingly maintained at nominally constant altitude during the transition mode; greater than 100%, wherein the air vehicle is correspondingly caused to climb altitude during the transition mode; less than 100%, wherein the air vehicle is correspondingly caused to decrease altitude during the transition mode.
  • a non-transitory storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform operations of controlling operation of an air vehicle
  • the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis
  • the operations comprising, by the machine: generating at least one first command operable to control an aggregate thrust generated by the propulsion system for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode from vectored thrust flight mode to aerodynamic flight mode; generating at least one modified first command operable to increase said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle
  • a control system to control operation of an air vehicle, wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, the control system comprising a processing unit and associated memory configured to generate one or more commands comprising: at least one first command operable to control an aggregate thrust generated by the propulsion system much higher than a weight of the air vehicle for enabling rapid vertical acceleration of the air vehicle while operating in vectored thrust flight mode, at least one modified first command operable to decrease said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle at a desired level of matching, at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode from vectored thrust flight mode to aerodynamic flight mode.
  • said one or more commands further comprises at least one further modified first command operable to reduce said aggregate thrust generated by the propulsion system to cause summation of the vertical component of said aggregate thrust and an aerodynamic lift generated by the wings to match a weight of the air vehicle at said desired level of matching.
  • said level of matching is one of the following:
  • an air vehicle comprising a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, and the control system as defined herein according to the fourth aspect of the presently disclosed subject matter.
  • a method of controlling operation of an air vehicle wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, the method comprising, by a processing unit and associated memory operatively coupled to the air vehicle: generating at least one first command operable to control an aggregate thrust generated by the propulsion system much higher than a weight of the air vehicle for enabling rapid vertical acceleration of the air vehicle while operating in vectored thrust flight mode, generating at least one modified first command operable to decrease said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle at a desired level of matching, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode from vectored thrust flight mode to aerodynamic flight mode.
  • said one or more commands further comprises generating at least one further modified first command operable to reduce said aggregate thrust generated by the propulsion system to cause summation of the vertical component of said aggregate thrust and an aerodynamic lift generated by the wings to match a weight of the air vehicle at said desired level of matching.
  • said level of matching is one of the following:
  • a non-transitory storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform operations of controlling operation of an air vehicle
  • the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis
  • the operations comprising, by the machine: generating at least one first command operable to control an aggregate thrust generated by the propulsion system much higher than a weight of the air vehicle for enabling rapid vertical acceleration of the air vehicle while operating in vectored thrust flight mode, generating at least one modified first command operable to decrease said aggregate thrust generated by the propulsion system to cause a vertical component of said aggregate thrust to match a weight of the air vehicle at a desired level of matching, generating at least one second command operable to separately control individual thrusts of the individual propulsion units to provide control moments in at least pitch during transition mode
  • a method for landing an air vehicle wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, wherein the air vehicle is configured for operating in vectored thrust flight mode, aerodynamic flight mode, and transition mode, and wherein the air vehicle comprises a fuselage portion aft of the wing arrangement, the method comprising:
  • the method further comprises the step (d) of reducing a thrust generated by propulsion system to zero.
  • a feature of at least one example of the presently disclosed subject matter is that an air vehicle is provided capable of being operated in aerodynamic flight mode, vectored flight mode, and transition mode between the aerodynamic flight mode and the vectored flight mode, while having a relatively simple construction.
  • Another feature of at least one example of the presently disclosed subject matter is that an air vehicle is provided with no moving parts other than the rotors of the propulsion units.
  • an air vehicle is provided with roll control that is essentially uncoupled with respect to pitch and/or to yaw.
  • Another feature of at least one example of the presently disclosed subject matter is that an air vehicle is provided which is graspable by one hand of a user.
  • Another feature of at least one example of the presently disclosed subject matter is that an air vehicle is provided which can be effectively landed by being grasped by one hand of a human user.
  • an air vehicle configured for transitioning between the aerodynamic flight mode and the vectored flight mode at nominally constant altitude.
  • an air vehicle configured for transitioning the aerodynamic flight mode and the vectored flight mode after a period of rapid vertical acceleration and during subsequent gravitational deceleration within a nominally constant altitude.
  • Fig- 1 is a top-front-side isometric view of an air vehicle according to an example of the presently disclosed subject matter.
  • Fig- 2 is a front view of the example of Fig. 1.
  • Fig. 3 is a top view of the example of Fig. 1;
  • Fig. 3A is a lateral view of the example of Fig. 3 taken along a direction DD of Fig. 2 parallel to a root-to-tip direction of one wing of the air vehicle.
  • Fig- 4 is a side view of the example of Fig. 1.
  • Fig. 5 is a top-front-side isometric view of the example of Fig. 1 aft of plane PL of Fig. 4.
  • Fig. 6 is a detail of part of the example of Fig. 5 in top -front- si de isometric view.
  • Fig. 7 is a detail of part of the example of Fig. 5 in front view.
  • Fig. 8 is a detail of part of the example of Fig. 5 in side view.
  • Fig. 9 is a detail of part of the example of Fig. 5 in top view.
  • Fig. 10A schematically illustrates in side view an alternative variation of the example of propulsion unit of the example of Fig. 1;
  • Fig. 10B schematically illustrates in top view the example of Fig. 10A
  • Fig. 11 is an isometric exploded view of the example of Fig. 1.
  • Fig. 12A schematically illustrates in front view an alternative variation of the example of Fig. 1
  • Fig. 12B schematically illustrates in front view another alternative variation of the example of Fig. 1
  • Fig. 12C schematically illustrates in front view another alternative variation of the example of Fig. 1.
  • Fig. 13 schematically illustrates in front view another alternative variation of the example of Fig. 1,
  • Fig. 14 is a schematic representation of a control system of an air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 15 is a flow chart of a method of controlling the air vehicle using a control system of an air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 16A is a flow chart of a method of controlling hover in vectored thrust mode of an air vehicle using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 16B is a flow chart of a method of controlling climb of an air vehicle in vectored thrust mode using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 16C is a flow chart of a method of controlling descent of an air vehicle in vectored thrust mode using a control system of the air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 17A is a side view of the example of Fig. 1 providing hover control in vectored thrust flight mode
  • Fig. 17B is a side view of the example of Fig. 1 providing climb control in vectored thrust flight mode
  • Fig. 17C is a side view of the example of Fig. 1 providing descent control in vectored thrust flight mode.
  • Fig. 18A is a side view of the example of Fig. 1 providing pitch control in vectored thrust flight mode
  • Fig. 18B is a top view of the example of Fig. 1 providing yaw control in vectored thrust flight mode
  • Fig. 18C is a side view of the example of Fig. 1 providing roll control in vectored thrust flight mode.
  • Fig. 19A is a flow chart of a method of controlling pitch in vectored thrust mode of an air vehicle using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 19B is a flow chart of a method of controlling yaw of an air vehicle in vectored thrust mode using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 19C is a flow chart of a method of controlling roll of an air vehicle in vectored thrust mode using a control system of the air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 20A is a side view of the example of Fig. 1 providing constant forward speed control in aerodynamic flight mode
  • Fig. 20B is a side view of the example of Fig. 1 providing forward acceleration control in aerodynamic thrust flight mode
  • Fig. 20C is a side view of the example of Fig. 1 providing forward deceleration control in aerodynamic flight mode.
  • Fig. 21A is a flow chart of a method of controlling constant forward speed in aerodynamic mode of an air vehicle using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 21B is a flow chart of a method of controlling forward acceleration of an air vehicle in aerodynamic flight mode using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 21C is a flow chart of a method of controlling forward deceleration of an air vehicle in aerodynamic flight mode using a control system of the air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 22A is a side view of the example of Fig. 1 providing pitch control in aerodynamic flight mode
  • Fig. 22B is a top view of the example of Fig. 1 providing yaw control in aerodynamic flight mode
  • Fig. 22C is a side view of the example of Fig. 1 providing roll control in aerodynamic flight mode.
  • Fig. 23A is a flow chart of a method of controlling pitch in aerodynamic flight mode of an air vehicle using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 23B is a flow chart of a method of controlling yaw of an air vehicle in aerodynamic flight mode using a control system of the air vehicle according to an example of the presently disclosed subject matter
  • Fig. 23C is a flow chart of a method of controlling roll of an air vehicle in aerodynamic flight mode using a control system of the air vehicle according to an example of the presently disclosed subject matter.
  • Fig. 24A schematically illustrates a side view of the example of Fig. 1 at one stage of a transition mode from vectored thrust flight mode to aerodynamic flight mode, according to a first example of the presently disclosed subject matter, in which the air vehicle is in vectored thrust mode;
  • Fig. 24B schematically illustrates the example of Fig. 24A at a subsequent stage of the transition mode including pitching;
  • Fig. 24C schematically illustrates the example of Fig. 24B at a subsequent stage of the transition mode including further pitching;
  • Fig. 24D schematically illustrates the example of Fig. 24C at a subsequent stage of the transition mode including further pitching and generation of significant aerodynamic lift;
  • Fig. 24E schematically illustrates the example of Fig. 24D wherein the air vehicle is in aerodynamic flight mode.
  • Fig. 25 is a flow chart of a method of controlling transition of an air vehicle from vectored thrust mode to in aerodynamic flight mode using a control system of the air vehicle according to a first example of the presently disclosed subject matter.
  • Fig. 26A schematically illustrates a side view of the example of Fig. 1 at one stage of a transition mode from vectored thrust flight mode to aerodynamic flight mode, according to a second example of the presently disclosed subject matter, in which the air vehicle is in vectored thrust mode;
  • Fig. 26B schematically illustrates the example of Fig. 26A at a subsequent stage of the transition mode including pitching;
  • Fig. 26C schematically illustrates the example of Fig. 26B at a subsequent stage of the transition mode including further pitching;
  • Fig. 26D schematically illustrates the example of Fig. 26C at a subsequent stage of the transition mode including further pitching;
  • Fig. 26E schematically illustrates the example of Fig. 26D wherein the air vehicle is in aerodynamic flight mode.
  • Fig. 27 is a flow chart of a method of controlling transition of an air vehicle from vectored thrust mode to in aerodynamic flight mode using a control system of the air vehicle according to a second example of the presently disclosed subject matter.
  • Fig. 28 schematically illustrates an altitude vs range trajectory for an air vehicle using the method of the example of Fig. 25.
  • Fig. 29 schematically illustrates an altitude vs range trajectory for an air vehicle using the method of the example of Fig. 27. DETAILED DESCRIPTION
  • a first example of an air vehicle is generally designated 100, and comprises a fuselage 200, wing system 300 and propulsion system 500.
  • An orthogonal Cartesian axis system including a roll axis R, a pitch axis P, and a yaw axis Y, can be defined with respect to the air vehicle 100.
  • the roll axis R is co-axial with the longitudinal axis LA of the air vehicle 100, which is coextensive with the fuselage 200.
  • the pitch axis P and the yaw axis Y are orthogonal to one another, and also orthogonal with respect to the roll axis R.
  • a yaw-pitch plane YP can be defined along the yaw axis Y and the pitch axis P, and orthogonal to the roll axis R.
  • a yaw-roll plane YR can be defined along the yaw axis Y and the roll axis R, and orthogonal to the pitch axis P.
  • a roll-pitch plane RP can be defined along the roll axis R and the pitch axis P, and orthogonal to the yaw axis Y.
  • the fuselage 200 is, in at least this example, generally elongate, having a nose 210 and tail 290. Furthermore, while in at least this example, has a circular transverse crosssection, in at least some alternative variations of this example the fuselage 200 can have any suitable cross-sectional shape, for example oval, elliptical, superelliptical, polygonal, and so on.
  • the fuselage 200 is hollow, and accommodates a power pack 220 (for example electrical battery pack), communications module 230, guidance control, cables and so on.
  • a power pack 220 for example electrical battery pack
  • communications module 230 for example, GPS navigation, satellites, and so on.
  • the fuselage 200 can accommodate ordinance, for example explosives.
  • ordinance can be configured for detonating on impact of the air vehicle 100 onto a target, or for detonating when the air vehicle 100 is at a predetermined proximity to a target, or for detonating responsive to receiving an appropriate signal from an external source via the communication module 230, or for detonating via a preset timer, for example.
  • the nose 210 comprises a forward-looking camera 205, operatively coupled to the communications module, enabling video and/or still images captured by the camera 205 to be transmitted externally via the communication module 230.
  • the camera can be omitted, and/or, other cameras can be installed in other parts of the air vehicle 100.
  • the fuselage 200 also accommodates a control system 250, operatively coupled to the communication module 230, as well as to the propulsion system 500.
  • the control system 250 is configured for operating the propulsion system 500 to enable the air vehicle 100 to operate in vectored thrust mode VTM, in aerodynamic flight mode AFM, and in transition mode TRM (wherein the air vehicle 100 transitions between the vectored thrust mode VTM and the aerodynamic flight mode AFM). Furthermore, the control system 250 is configured for operating the propulsion system 500 to generate control moments to the air vehicle 100 in any one of or combination of pitch, yaw, and roll, in all modes of operation, including vectored thrust mode VTM, aerodynamic flight mode AFM, and in transition mode TRM.
  • control system 250 is configured for operating the propulsion system 500 to cause the air vehicle to: accelerate, or decelerate, or maintain a constant forward speed in aerodynamic mode; or to: accelerate, or decelerate, or climb, or descend, or maintain hover in vectored thrust mode.
  • the air vehicle 100 includes a sensor package including a position sensor 253 (e.g., GPS, etc.), a velocity sensor and/or acceleration sensor 256, altimeter 254, attitude sensor 255 (configured to provide data informative of at least one of a pitch, yaw and roll of the air vehicle 100).
  • a position sensor 253 e.g., GPS, etc.
  • a velocity sensor and/or acceleration sensor 256 e.g., a velocity sensor and/or acceleration sensor 256
  • altimeter 254 e.g., attitude sensor 255 (configured to provide data informative of at least one of a pitch, yaw and roll of the air vehicle 100).
  • the fuselage 200 comprises an empennage 270.
  • the empennage comprises port and starboard horizontal stabilizers 272, and upper and lower vertical stabilizers 274, arranged in cruciform "+" arrangement in proximity to the tail 290.
  • the respective air vehicle can omit an empennage, or, the respective air vehicle can have a different arrangement for the respective empennage.
  • the air vehicle 100 is configured for enabling the air vehicle to be graspable by a hand of a human user, for example when the air vehicle 100 is in a hovering condition, or when it is desired for the air vehicle to take off from a ground location.
  • the empennage 270 is axially spaced from the wing system 300 along the longitudinal axis LA by a spacing ARX (Fig. 3).
  • a spacing ARX is at least the size of a width of a hand, for example the width of a hand of a 50 th percentile male.
  • a spacing is not less than about 5cm.
  • the diameter of the fuselage in this section is also such as to enable circumferentially to grasp the air vehicle 100 via a human hand, for example of a 50 th percentile human male; for example, the diameter is about 10cm.
  • the air vehicle 100 can be hand-held by a user, by grasping with one hand the aft end of the fuselage between the empennage 270 is and the wing system 300. This can be useful when it is desired to cause the air vehicle to take off in vectored thrust mode, without the need for a stand or other structures to hold the air vehicle until it is able to fly.
  • the wing system 300 comprises four wings 320.
  • the four wings include a pair of port wings 320PT, 320PB, and a pair of starboard wings 320ST, 320SB.
  • the four wings 320 are in X-arrangement with respect to the fuselage 200.
  • X- arrangement is meant that the four wings 320 when viewed in a direction along the longitudinal axis LA of the air vehicle 100, form a general "X" shape.
  • the top port wing 320PT is angled (along a plane parallel to the yaw-pitch plane YP) with respect to the bottom port wing 320PB, by a port wing angle 0p
  • the top starboard wing 320ST is angled (along a plane parallel to the yaw-pitch plane YP) with respect to the bottom starboard wing 320SB, by a starboard wing angle 0s.
  • port wing angle 0p and the starboard wing angle 0s are each about 40°.
  • the respective port wing angle 0p and the starboard wing angle 0s can be any desired angle within the range 30° to 60° or 90° ⁇ 5°
  • the top port wing 320PT and the top starboard wing 320ST intersect at a first point PT1 that is vertically spaced from the longitudinal axis LA; the bottom port wing 320PB and the bottom starboard wing 320SB intersect at a second point PT2 that is vertically spaced from the longitudinal axis LA.
  • An imaginary rectilinear line joining the first point PT1 and the second point PT2 intersects the longitudinal axis LA and/or roll axis R.
  • the top port wing 320PT is overlying the bottom port wing 320PB along a direction parallel to the yaw axis Y
  • the top starboard wing 320ST is overlying the bottom starboard wing 320SB along a direction parallel to the yaw axis Y.
  • the wings 320 have zero sweep, and have a rectangular planform, with a uniform chord distribution from the respective root 321 to the respective tip 329.
  • the respective wing can have a non-zero sweep angle, and/or can have a non- rectangular planform, for example trapezoidal.
  • the wings 320 have a camber and the respective chords are inclined with respect to the longitudinal axis LA at a non-zero incidence angle of about 3.5° such that when the air vehicle 100 is traveling at zero angle of attack a in straight horizontal flight, the aerodynamic lift L generated by the wings 320 balances the weight W of the air vehicle.
  • the wings 320 are devoid of any movable control surfaces, and of any actuators that would otherwise be required for operating such control surfaces.
  • the wings have a fixed geometry during all stages (of aerodynamic flight mode, during transition mode and during vectored flight mode, including while performing one or more of yaw, pitch and roll maneuvers during any one of aerodynamic flight mode, transition mode and vectored flight mode.
  • the wings 320 are affixed to the fuselage 200 in fixed spatial relationship, and thus the wings are not movable or pivotable with respect to the fuselage 200, at least when the air vehicle 100 is assembled and ready for flight.
  • the propulsion system 500 comprises four propulsion units 550.
  • the propulsion units 550 are individually designated herein also with reference numerals 550PT, 550PB, 550ST, 550SB which respectively refer to the port top propulsion unit, the port bottom propulsion unit, the starboard top propulsion unit, and the starboard bottom propulsion unit.
  • the propulsion system can comprise more than four propulsion units.
  • one or more additional propulsion units can be provided in which each respective thrust vector is parallel with the roll axis R of the air vehicle.
  • two or more propulsion units can be provided for each wing, wherein for example the respective thrust vectors are parallel to one another for each set of propulsion units on a respective wing.
  • each propulsion unit 550 comprises a ducted fan arrangement, including a respective fan (not shown), rotatably mounted about a respective rotational axis RA in a generally cylindrical duct 554, having a respective duct inlet 553 and a respective duct outlet 555.
  • the propulsion units 550 are electrically powered, and an electric motor (not shown) is accommodated within the respective duct 554, the motor shaft being co-axial with the respective rotational axis RA.
  • the respective fan (not shown) is mounted to the respective motor shaft to turn therewith when the electric motor is operating and turning the shaft.
  • the respective fan and motor are concentrically mounted within the respective duct 554 via a plurality of struts 558.
  • the duct inlet 553 is dimensioned such as to prevent or minimize the risk of a human hand and fingers being inserted into the ducted fan arrangement, at least such that otherwise could allow the fingers to come into contact with the internal fan, and thus potentially cause injury to the user and/or damage the propulsion unit 550.
  • the circumferential spacing between adjacent struts 558 can be smaller than for example the width of a hand of a 50 th percentile male, i.e., of an adult human male. For example, such a spacing is not greater than about 5cm.
  • the fan is axially displaced from the forward edge of the respective inlet duct inlet 553 by a spacing greater than the length between the outermost fingertip and the base of the thumb of a hand of a 50 th percentile male, i.e., of an adult human male.
  • a spacing is not less than about 5cm.
  • a ratio of the diameter of the forward edge of the respective inlet duct inlet 553 to an axial length of the duct 554 along the respective rotor axis RA is about 1.
  • the ratio of the diameter of the forward edge of the respective inlet duct inlet to an axial length of the respective duct along the respective rotor axis can be different from about 1.
  • each propulsion unit can be instead configured as a propeller-based propulsion unit, or as a turbojet-based propulsion unit or as a propfan-based propulsion unit; additionally or alternatively, each respective propulsion unit can be powered by electrically power or liquid fuel where suitable, or can include a hybrid power source including both electrical power and liquid fuel.
  • Each propulsion unit 550 thus generates a respective thrust T along a respective thrust vector TV.
  • the thrust vector TV is co-axial with the respective rotational axis RA.
  • the thrust vector direction for each propulsion units 550 is fixed with respect to air vehicle 100, and the air vehicle 100 is not capable of changing spatial orientation of the thrust vectors with respect to air vehicle 100, particular during aerial operation thereof.
  • the respective thrust T can be considered as acting on a point PT on the respective rotational axis RA.
  • the axial location of the respective duct outlet 555 along the respective rotational axis RA defines the respective point PT.
  • the respective points PT of the four propulsion units 550 lie on a thrust plane TP parallel to the yaw-pitch plane YP.
  • the thrust plane TP intersects the roll axis R at or close to the longitudinal location of the center of gravity CG of the air vehicle 100.
  • the thrust plane TP intersects the roll axis R at a longitudinal location aft of the center of gravity CG of the air vehicle 100, by a spacing which is about 20% of the wing chord.
  • the thrust plane TP can instead intersect the roll axis R at any other suitable longitudinal location fore or aft of the center of gravity CG of the air vehicle 100.
  • the air vehicle is aerodynamically stable, and has a static margin of about 12% of the wing chord.
  • Each propulsion unit 550 is fixedly mounted with respect to the fuselage 200 in laterally spaced relationship with respect to the roll axis R, via the wing arrangement 300.
  • each propulsion unit 550 is fixedly mounted to a respective wing 320 in the aforesaid laterally spaced relationship with respect to the roll axis R.
  • the lateral spacing between each propulsion unit 550 and the roll axis R provides a moment arm MA for roll, as will become clearer herein.
  • each propulsion unit 550 is fixedly mounted to the respective wing tip 329 of the respective wing 320.
  • each propulsion units 550 is fixedly mounted to the respective wing 320 such as to ensure that respective thrust vector TV is inclined with respect to the roll axis R in a manner such that the respective thrust T has a non-zero thrust component Tc defined on a reference plane PL orthogonal to the roll axis R.
  • the respective thrust T has a non-zero thrust component TR parallel to the roll axis R.
  • the non-zero thrust component Tc along the reference plane PL has a non-zero moment arm MA (magnitude MAo) with respect to the roll axis R, the moment arm MA also being defined along the reference plane PL
  • the reference plane PL is at least parallel to the yaw-pitch plane YP, and can be located at any suitable location along the roll axis R.
  • the reference plane PL can intersect the roll axis R at or close to the longitudinal location of the center of gravity CG of the air vehicle 100.
  • the thrust plane TP and the reference plane RP are co-planar.
  • the thrust plane TP and the reference plane RP are axially spaced from one another along the roll axis via a desired spacing.
  • the non-zero thrust component Tc is defined on the reference plane PL, the non-zero thrust component Tc is inclined with respect to the pitch axis P and with respect to the yaw axis Y.
  • the non-zero thrust component Tc can thus be resolved into a first thrust component TCY parallel to the yaw axis Y, and a second thrust component TCP parallel to the pitch axis P.
  • the respective first thrust component TCY is directed towards the roll axis R (in side view), while the respective second thrust component TCP is directed away from the roll axis R (in top view).
  • the aforesaid laterally spaced relationship with respect to the roll axis R is achieved by orienting the propulsion units 550 such that the respective thrust vectors TV are non-parallel to one another.
  • the port pair of adjacent propulsion units 550PT, 550PB, and the starboard pair of adjacent propulsion units 550ST, 550SB are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are non-parallel to one another. Furthermore, in each such pair, the respective thrust vectors TV are converging in a forward direction (in a plane parallel to the yaw-roll plane YR, i.e., in the side view illustrated in Fig. 4) towards a forward converging point FCP. It is to be noted that the forward converging point FCP is not on the longitudinal axis LA, but rather laterally displaced therefrom.
  • the top pair of adjacent propulsion units 550PT, 550ST, and the bottom pair of adjacent propulsion units 550PB, 550SB are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are non-parallel to one another. Furthermore, in each such pair, the respective thrust vectors TV are diverging in a forward direction (in a plane parallel to the roll-pitch plane RP, i.e., in the top view illustrated in Fig. 3) by a respective first vector angle H with respect to the roll axis R, away from an aft diverging point ADP. It is to be noted that the aft converging point ACP is not on the longitudinal axis LA, but rather vertically displaced therefrom.
  • the port pair of adjacent propulsion units 550PT, 550PB, and the starboard pair of adjacent propulsion units 550ST, 550SB are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are diverging in a forward direction (in a plane parallel to the yaw-roll plane YR) away from an aft diverging point.
  • the top pair of adjacent propulsion units 550PT, 550ST, and the bottom pair of adjacent propulsion units 550PB, 550SB are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are converging in a forward direction (in a plane parallel to the roll-pitch plane RP) towards a forward converging point.
  • the non-zero thrust component Tc is inclined to the yaw axis Y (along the reference plane PL) by an inclination angle 0o, which is related to the relative magnitudes of the first thrust component TCY and second thrust component TCP as follows:
  • the moment arm MA is orthogonal to the non-zero thrust component Tc, thereby generating a roll control moment MR about the roll axis R. Furthermore, in at least this example, the respective point PT is located at the extremity of the moment arm MA. Accordingly, for a given magnitude of respective thrust T along the respective thrust vector TV, the magnitude MAo of the respective moment arm MA from the non-zero thrust component Tc to the roll axis R is maximized.
  • the moment arm MA for any particular magnitude of port wing angle 0p and the starboard wing angle 0s for the respective wing system can be maximized by matching the inclination angle 0o to half the magnitude of the port wing angle 0p or of the starboard wing angle 0s such that an imaginary line IL connecting the respective point PT to the roll axis R (along the reference plane PL) is also at the inclination angle 0o with respect to the pitch axis P, as illustrated in Fig. 7.
  • an imaginary line IL and the moment arm MA coincide with one another, i.e., are co-axial.
  • the respective moment arm MA does not pass through the respective point PT.
  • the respective roll moment that can be generated about the roll axis R is correspondingly less than when the respective moment arm passes through the respective point PT.
  • the port pair of adjacent propulsion units 550PT, 550PB, and the starboard pair of adjacent propulsion units 550ST, 550SB can be oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are diverging or converging in a forward direction (in a plane parallel to the yaw-roll plane YR) away from an aft diverging point; while concurrently the top pair of adjacent propulsion units 550PT, 550ST, and the bottom pair of adjacent propulsion units 550PB, 550SB, are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are parallel to one another (in a plane parallel to the roll-pitch plane
  • the port pair of adjacent propulsion units 550PT, 550PB, and the starboard pair of adjacent propulsion units 550ST, 550SB are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are parallel with one another (in a plane parallel to the yaw-roll plane YR); while concurrently the top pair of adjacent propulsion units 550PT, 550ST, and the bottom pair of adjacent propulsion units 550PB, 550SB, are oriented with respect to the roll axis R such that in each such pair the respective thrust vectors TV are converging or diverging in a forward direction (in a plane parallel to the roll-pitch plane RP) towards a forward converging point.
  • the aforementioned spatial relationship is such that the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB each provide a roll control moment MR in a counter-clockwise direction in the view seen in this figure, while the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT each provide a roll control moment MR in a clockwise direction in the view seen in this figure.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate an increased thrust (equal to one another), as compared with the thrust generated by the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB (also equal to one another).
  • the resulting nose-down pitch moment is greater than the resulting nose-up pitch moment, thereby generating a net nose-down pitch moment about the pitch axis P.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate an increased thrust (equal to one another), as compared with the thrust generated by the starboard top propulsion unit 550TB and the port top propulsion unit 550PT (also equal to one another).
  • the resulting nose-up pitch moment is greater than the resulting nose-down pitch moment, thereby generating a net nose-up pitch moment about the pitch axis P.
  • Each one of the aforesaid net nose-up moment about the pitch axis P and the aforesaid net nose-down moment about the pitch axis P can be generated during vectored thrust flight mode, during transition mode, and during aerodynamic flight mode.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB to each generate an increased thrust (equal to one another), as compared with the thrust generated by the port top propulsion unit 550PB and the port bottom propulsion unit 550PB (also equal to one another).
  • the resulting yaw moment to port is greater than the resulting yaw moment to starboard, thereby generating a net port yaw moment about the yaw axis Y.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the port top propulsion unit 550PB and the port bottom propulsion unit 550PB to each generate an increased thrust (equal to one another), as compared with the thrust generated by the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB (also equal to one another).
  • the resulting yaw moment to starboard is greater than the resulting yaw moment to port, thereby generating a net starboard yaw moment about the yaw axis Y.
  • Each one of the aforesaid net port moment about the yaw axis Y and the aforesaid net starboard moment about the yaw axis Y can be generated during vectored thrust flight mode, during transition mode, and during aerodynamic flight mode.
  • the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB each generate a respective roll moment MR in a counter clockwise direction (in the front view of Fig. 2)
  • the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT each generate a respective roll moment MR in a clockwise direction (in the front view of Fig. 2). Since the respective moment arms MA are the same for the four propulsion units 550, when the four propulsion units 550 generate equal thrust T one to the other, the clockwise roll moments and the counter clockwise roll moments cancel each other out and there is no net roll moment generated.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB to each generate an increased thrust (equal to one another), as compared with the thrust generated by the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT (also equal to one another).
  • the resulting counter clockwise roll moment is greater than the resulting clockwise roll moment, to thereby generate a net counter clockwise roll moment about the roll axis R.
  • the propulsion system 500 is controlled (for example via the control system 250) by causing the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT to each generate an increased thrust (equal to one another), as compared with the thrust generated by the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB (also equal to one another).
  • the resulting clockwise roll moment is greater than the resulting counter clockwise roll moment, thereby generating a net clockwise moment about the roll axis R.
  • Each one of the aforesaid net counter clockwise moment about the roll axis R and the aforesaid net clockwise moment about the roll axis R can be generated during vectored thrust flight mode, during transition mode, and during aerodynamic flight mode.
  • the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT generate equal thrust one to the other, and while the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB generate equal thrust one to the other.
  • the propulsion system 500 does not concurrently generate any concurrent net pitching moment or any concurrent yaw moment, and thus there is no respective coupling, since:
  • the total forward thrust generated by the top pair of propulsion units 550ST, 550PT is equal to the total forward thrust generated by the bottom pair of propulsion units 550SB, 550PB, and thus no net pitch moment is generated;
  • the total forward thrust generated by the starboard pair of propulsion units 550ST, 550SB is equal to the total forward thrust generated by the port pair of propulsion units 550PT, 550PB, and thus no net yaw moment is generated.
  • the propulsion system 500 can be operated (via the control system 250) to provide any desired maneuver in pitch and/or roll and/or yaw by suitably controlling the relative levels of thrust generated by each one of the four propulsion units 550 to provide the desired concurrent combination of any two or more of pitch moments, roll moments, and yaw moments.
  • the propulsion system 500 generates sufficient total thrust via the four propulsion units 550 to maintain the air vehicle in each one of aerodynamic flight mode, transition mode, and vectored flight mode.
  • the control system 250 controls the thrust generated by each one of the propulsion units 550 to, on the one hand together generate the total thrust required for maintaining the air vehicle in aerodynamic flight mode, transition mode, or vectored flight mode, while concurrently providing different relative levels of thrust to enable the desired roll, pitch and/or yaw moments to be generated.
  • the thrust vector TV is co-axial with the respective rotational axis RA.
  • the thrust vector TV is parallel with, and laterally displaced with respect to, the respective rotational axis RA.
  • each respective propulsion units 550' can be configured such that the respective thrust vector TV can be, instead, non co-axial with the respective rotational axis RA.
  • the thrust vector TV is at a first angle ⁇
  • >v, taken together with the orientation of the respective rotor axis RA', are such as to orient the respective thrust vector TV with respect to the roll axis R at the respective first vector angle XH and the respective second vector angle Xv, respectively.
  • the respective rotational axis RA' can be parallel to the roll axis R, and thus the first angle ⁇
  • the respective second vector angle Xv has a greater absolute magnitude than the first vector angle XH.
  • the respective second vector angle Xv has a greater absolute magnitude of about 7.5°, and in at least some alternative variations of this example can be in the range from about 2° to about 10°, for example.
  • the respective first vector angle XH has a greater absolute magnitude of about 5°, and in at least some alternative variations of this example can be in the range from about 1° to about 8°, for example.
  • the air vehicle 100 can be constructed in a modular manner, to enable quick and easy assembly, even in the field.
  • the air vehicle 100 can be provided in a disassembled manner, which enables compact packing of the air vehicle 100 into a small volume, and the various air vehicle parts can be assembled together to provide the air vehicle.
  • a first example of an air vehicle according to this aspect of the presently disclosed subject matter corresponds to the air vehicle 100 disclosed herein and with reference to Figs. 1 to 10, mutatis mutandis, in the disassembled configuration, and the air vehicle 100 is assembled from a plurality of parts including: a fuselage part 1200, a top wing part 250, a bottom wing 1320, and a battery pack 1400.
  • the fuselage part 1200 essentially corresponds to the fuselage 200 mutatis mutandis, wherein a top section 1210 and a bottom section 1220 of the fuselage 200 are essentially cutout to allow access into the fuselage.
  • the top wing part 250 comprises the starboard top wing 320ST, the starboard top propulsion unit 550ST, the port top wing 320PT and the port top propulsion unit 550PT, and a top wing interconnector 1305.
  • the top wing interconnector 1305 interconnects the starboard top wing 320ST and the port top wing 320PT.
  • the top wing interconnector 1305 comprises a bottom zone 1306 configured for being affixed with respect to the top section 1210.
  • the bottom zone 1306 and the top section 1210 are configured for enabling quick assembly between the fuselage section 1200 and the top wing part 250.
  • one or both of the bottom zone 1306 and the top section 1210 comprises a suitable fixing arrangement for enabling such fixation.
  • fixation can be carried out using fasteners, for example screws or bolts; alternatively, the bottom zone 1306 and the top section 1210 can be shaped or include suitable elements that enable the bottom zone 1306 and the top section 1210 to engage together without the need for fasteners.
  • fasteners for example screws or bolts
  • the bottom zone 1306 and the top section 1210 can be shaped or include suitable elements that enable the bottom zone 1306 and the top section 1210 to engage together without the need for fasteners.
  • the bottom wing part 1320 comprises the starboard bottom wing 320SB, the starboard bottom propulsion unit 550SB, the port bottom wing 320PB and the port bottom propulsion unit 550PB, and a bottom wing interconnector 1325.
  • the bottom wing interconnector 1325 interconnects the starboard bottom wing 320SB and the port bottom wing 320PB.
  • the bottom wing interconnector 1325 comprises a top zone 1326 configured for being affixed with respect to the bottom section 1220.
  • the top zone 1326 and the bottom section 1220 are configured for enabling quick assembly between the fuselage section 1200 and the bottom wing part 1320.
  • one or both of the top zone 1326 and the bottom section 1220 comprises a suitable fixing arrangement for enabling such fixation.
  • the respective wing system 300 is in the form of an X- wing arrangement, in at least some alternative variations of these examples, the respective wing system can include different wing arrangements.
  • the respective air vehicle 100A comprises a respective fuselage 200A, a respective wing system 300A, and a propulsion system 500A, similar to the air vehicle 100, fuselage 200, wing system 300 and propulsion system 500, as described herein mutatis mutandis, with some differences as disclosed herein.
  • the wing system 300A comprises a single port wing 320P and a single starboard wing 320S, each having a pair of wing tip extensions 330A. In each one of the port wing 320P and the starboard wing 320S, the two respective wing extensions 330A project vertically in opposite directions.
  • the propulsion system 500A includes at least four propulsion units 550A, similar to the propulsion units 550, mutatis mutandis.
  • Each propulsion unit 550A is affixed to a free end of a respective wing extension 330A at a suitable orientation with respect thereto such that the respective fixed thrust vector is at a respective laterally spaced relationship with respect to the roll axis R.
  • the respective thrust generated along the thrust vector for each propulsion unit 550A has a respective nonzero thrust component along a respective reference plane orthogonal to the roll axis R, and this non-zero thrust component has a non-zero moment arm (defined along the reference plane) with respect to the roll axis R, in a similar manner to the example disclosed herein and illustrated in Figs. 1 to 11, mutatis mutandis.
  • the respective air vehicle 100B comprises a respective fuselage 200B, a respective wing system 300B, and a propulsion system 500B, similar to the air vehicle 100, fuselage 200, wing system 300 and propulsion system 500, as described herein mutatis mutandis, with some differences as disclosed herein.
  • the wing system 300B comprises an upper wing 320T (having port and starboard wing portions) and a bottom wing 320B (having port and starboard wing portions), the two wings 320T and 320B being joined together at the respective port wing tips and at the respective starboard wing tips via wing tip extensions 330B.
  • the propulsion system 500B includes at least four propulsion units 550B, similar to the propulsion units 550, mutatis mutandis.
  • Each propulsion unit 550B is affixed to the wing tips of the upper wing 320T and the lower wing 320B at a suitable orientation with respect thereto such that the respective fixed thrust vector is at a respective laterally spaced relationship with respect to the roll axis R.
  • the respective thrust generated along the thrust vector for each propulsion unit 550B has a respective non-zero thrust component along a respective reference plane orthogonal to the roll axis R, and this non-zero thrust component has a non-zero moment arm (defined along the reference plane) with respect to the roll axis R, in a similar manner to the example disclosed herein and illustrated in Figs. 1 to 11, mutatis mutandis.
  • the respective air vehicle 100C comprises a respective fuselage 200C, a respective wing system 300C, and a propulsion system 500C, similar to the air vehicle 100, fuselage 200, wing system 300 and propulsion system 500, as described herein mutatis mutandis, with some differences as disclosed herein.
  • the wing system 300C comprises an annular wing (also referred to as a cylindrical wing or as a ring wing) having an upper wing segment 320UC and a lower wing segment 320LC, the two wing segments being joined together at the respective port wing tips and at the respective starboard wing tips.
  • the wing segments 320UC and 320LC are connected to the fuselage 200C via struts 270C.
  • the propulsion system 500C includes at least four propulsion units 550C, similar to the propulsion units 550, mutatis mutandis.
  • a pair of propulsion unit 550C are fixed to each one of the upper wing 320UC and the lower wing 320B (for example at 45° to the vertical as seen in the view shown in Fig. 12C) at a suitable orientation with respect thereto such that the respective fixed thrust vector is at a respective laterally spaced relationship with respect to the roll axis R.
  • the respective thrust generated along the thrust vector for each propulsion unit 550C has a respective non-zero thrust component along a respective reference plane orthogonal to the roll axis R, and this non-zero thrust component has a non-zero moment arm (defined along the reference plane) with respect to the roll axis R, in a similar manner to the example disclosed herein and illustrated in Figs. 1 to 11, mutatis mutandis.
  • the respective air vehicle comprises a single fuselage
  • the respective air vehicle can include more than one fuselage.
  • the single fuselage of the examples shown in any one of Figs. 1 to 11, 12A, 12B, 12C can be replaced with two or more fuselages and connected to the respective wing system in a similar manner as disclosed herein mutatis mutandis.
  • Other arrangements are also possible. For example, referring to Fig.
  • the respective air vehicle 100D comprises a respective wing system 300C, and a propulsion system 500C, similar to the air vehicle 100, wing system 300 and propulsion system 500, as described herein mutatis mutandis
  • the air vehicle 100D comprises two fuselages 200D, each fuselage 200D being similar to the fuselage 200 as described herein mutatis mutandis, with some differences as disclosed herein.
  • the two fuselages 200D are laterally spaced from one another, on either side of the roll axis R.
  • the wing system 300D comprises an upper wing 320TD and a bottom wing 320BD.
  • the two wings are connected to each fuselage 200D at the respective port wing tips and at the respective starboard wing tips via wing tip extensions 330D.
  • the propulsion system 500D includes at least four propulsion units 550D, similar to the propulsion units 550, mutatis mutandis.
  • Each propulsion unit 550D is affixed to the wings tips of the upper wing 320TD and the lower wing 320BD at a suitable orientation with respect thereto such that the respective fixed thrust vector is at a respective laterally spaced relationship with respect to the roll axis R.
  • the respective thrust generated along the thrust vector for each propulsion unit 550D has a respective non-zero thrust component along a respective reference plane orthogonal to the roll axis R, and this non-zero thrust component has a non-zero moment arm (defined along the reference plane) with respect to the roll axis R, in a similar manner to the example disclosed herein and illustrated in Figs. 1 to 11, mutatis mutandis.
  • the air vehicle 100 is configured to operate in vectored thrust mode VTM, in aerodynamic flight mode AFM, and in transition mode TRM. While the following disclosure is based on the example illustrated in Figs. 1 to 11, it applies, mutatis mutandis, to the other examples disclosed herein, including the examples illustrated in Fig. 12A, Fig. 12B, Fig. 12C and Fig. 13.
  • FIG. 14 includes a schematic representation of an example of a control system 250 of the air vehicle 100.
  • Control system 250 includes a processing unit 251 and an associated memory 252. Various modules depicted in the control system 250 can be implemented using the processing unit 251 and the associated memory 252.
  • the control system 250 is operable to receive data from various sensors, such as for example position sensor 253 (e.g., GPS, etc.), velocity sensor 256, altimeter 254, attitude sensor 255 (configured to provide data informative of at least one of a pitch, yaw and roll of the air vehicle 100) This list is not limitative and optionally other sensors can communicate with control system 250.
  • Control system 250 includes a controller 260 configured to control operation of each of the propulsion units 550.
  • the controller 260 can generate a command which is common for all propulsion units 550, and/or can generate a command specific to each of the propulsion units 550.
  • the commands generated by the controller 260 can include a command for controlling a magnitude of a thrust of each of the propulsion units 550. For example, this can include controlling a rpm of the respective rotor arrangement of each propulsion unit 550.
  • Control system 250 can include, and/or communicate with, a flight controller 260, which is responsible inter alia of computing desired navigation parameters (such as position, velocity, trajectory, altitude, etc.) of the air vehicle 100 over time.
  • the navigation parameters can be compliant with a flight plan stored in a database (not represented).
  • navigation parameters can be controlled by an external central control 269 (e.g., controlled at least partially by a human operator) operatively and remotely coupled with the control system 250.
  • the central control 269 can be located on the ground, at sea or in the air, and can be static or mobile.
  • the air vehicle 100 can be controlled using autonomous navigation managed by the control system 250, and/or navigation commands can be transmitted from the central control 269 to the control system 250 (e.g., to correct autonomous navigation of the air vehicle 100, or, to navigate the air vehicle 100 to the final destination without autonomous navigation).
  • the controller 260 can generate appropriate commands to control the air vehicle 100 according to a desired flight mode complying with the flight plan, as explained hereinafter.
  • the air vehicle 100 comprises communications module 230 for emitting and/or receiving data towards and from, respectively, the central control 269.
  • the air vehicle 100 is at least partly controlled remotely from the central control 269, at least part of the steps performed by the control system 250 can be performed by a remote controller (which also operates on a processing unit) located at the central control 269.
  • the remote controller can communicate with the air vehicle 100 via the communications module 230, in order to perform the required steps.
  • the remote controller can receive data from the air vehicle 100, such as data measured by at least a subset of the air vehicle sensors.
  • the control system 250 accommodated in the air vehicle 100 can then communicate the orders (signals) received from the remote controller e.g., to the propulsion system 500 of the air vehicle 100.
  • control of magnitude of the thrust of the propulsion units 550 can be performed by the remote controller which communicates with the air vehicle 100.
  • control system 250 is split into a first control subsystem embedded in the air vehicle 100 and a second control sub-system located in the remote central control 269.
  • data computed in the air vehicle 100 can be displayed at the remote central control 269, for example for a human operator who can send remote commands to the air vehicle 100.
  • each such method can include e.g., obtaining data informative of a desired flight mode of the air vehicle.
  • flight modes include e.g., vectored thrust mode VTM (including vertical take-off, vertical landing, hovering), aerodynamic flight mode AFM (including aerodynamic forward flight), transition mode TRM (including transitioning from vectored thrust mode VTM to aerodynamic flight mode AFM, and transitioning from aerodynamic flight mode AFM to vectored thrust mode VTM), climb, descent, acceleration and deceleration (in either vectored thrust mode VTM, aerodynamic flight mode AFM or transition mode TRM), manoeuvring in pone or more of pitch, yaw and roll (in either vectored thrust mode VTM, aerodynamic flight mode AFM or transition mode TRM), and so on.
  • VTM including vertical take-off, vertical landing, hovering
  • aerodynamic flight mode AFM including aerodynamic forward flight
  • transition mode TRM including transitioning from vectored thrust mode VTM to aerodynamic flight mode AFM, and transitioning from aerodynamic flight
  • any other suitable air vehicle configuration that comprises a fuselage defining a roll axis, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, and in which the air vehicle is configured for enabling the air vehicle to operate in vectored thrust flight mode, aerodynamic flight mode, and transition mode.
  • the desired flight mode can be computed, for example by the flight controller 265.
  • Data informative of the desired flight mode can include desired parameters characterizing the desired flight mode (e.g., desired trajectory, position, velocity, or other parameters over time).
  • an example of a method 2000 according to this aspect of the presently disclosed subject matter includes generating (operation 2010) a first command for controlling the aggregate forward thrust TT generated by propulsion system 500, and in particular, a magnitude of the aggregate forward thrust TT.
  • the first command can include a desired rpm level for each of the respective rotors of the propulsion units 550.
  • the method includes generating (operation 2020) a second command for separately controlling the individual thrusts Tu of the propulsion units 550 to selectively provide differential thrusts, one from the other, while the propulsion system 500 concurrently provides the aforementioned desired level of aggregate forward thrust TT, to thereby enable generating control moments in one or more of pitch, yaw and roll.
  • the second command can include a desired change in rpm for the respective rotors of the propulsion units 550.
  • operations 2010 to 2020 can be performed concurrently, or can be performed in the order illustrated in Fig. 15, or in a different order from the order depicted in Fig. 15.
  • the first command 2010 and the second command 2020 can be generated and/or transmitted as a unified command.
  • the aggregate forward thrust TT and/or differential thrusts of the propulsion units 550 under control is/are already compliant with the desired flight mode and is therefore not changed.
  • an explicit command to maintain current state of aggregate forward thrust TT and/or differential thrusts can be generated and/or it is prevented from generating a new command for varying aggregate forward thrust TT and/or differential thrusts.
  • the first command and second commands are calibrated to provide a coordinated control of the propulsion units 550, ensuring operation of the air vehicle 100 according to the desired flight mode.
  • Various examples are provided hereinafter.
  • a magnitude of a thrust of the propulsion units 550 is controlled to generate the aggregate forward thrust TT in a vertical direction required for enabling vectored thrust flight to the air vehicle 100, i.e., to enable the air vehicle 100 to operate in vectored thrust mode VTM.
  • the propulsion units 550 can provide sufficient vertical thrust to at least balance the weight W of the air vehicle 100.
  • the propulsion units 550 can also be concurrently controlled to generate control moments in one or more of pitch, roll and yaw to the air vehicle 100 to thereby control attitude of the air vehicle 100 in pitch, roll and/or yaw, in order to reach a desired attitude of the air vehicle 100.
  • the propulsion units 550 for controlling variation of the altitude of the air vehicle 100, controlling attitude of the air vehicle 100 (along at least one of pitch axis, roll axis, yaw axis), ensuring forward flight, and so on, as disclosed herein.
  • vertical thrust generated by the propulsion units 550 is controlled to be sufficient to balance weight of the air vehicle 100, in particular when the air vehicle 100 is operated in vectored thrust mode VTM, and during some portions of operation in transition mode TRM. This can be obtained, for example, by selecting a sufficient rpm for the rotors of the propulsion units 550.
  • it is desired to induce a climb of the air vehicle 100 for example to cause the air vehicle 100 to climb to an altitude in vectored thrust mode VTM, from a previous flight condition in which the air vehicle 100 was not climbing (for example a flight condition in which the air vehicle 100 is hovering or descending) or in which the air vehicle 100 was climbing at a different rate to the climb rate currently being desired (for example, in order to increase climbing rate with respect to the previous climbing rate).
  • a previous flight condition in which the air vehicle 100 was not climbing for example a flight condition in which the air vehicle 100 is hovering or descending
  • a different rate to the climb rate currently being desired for example, in order to increase climbing rate with respect to the previous climbing rate
  • the method can include increasing the aggregate forward thrust TT of the propulsion units 550 when the air vehicle 100 is operated in vectored thrust mode VTM, or during some portions of operation in transition mode TRM, to maintain the aggregate forward thrust TT above a predefined threshold.
  • a threshold can correspond to the weight W of the air vehicle 100.
  • the air vehicle 100 has a maximum thrust to weight ratio TWR, i.e., maximum available aggregate forward thrust Trmax to weight W ratio significantly greater than 1.
  • TWR maximum available aggregate forward thrust Trmax to weight W ratio significantly greater than 1.
  • the thrust to weight ratio TWR is greater than 2, for example 3.
  • each motor generates 5kg, and weight is 10 kg.
  • the TWR can be less than 1.
  • the propulsion system 500 is operated to generate sufficient aggregate forward thrust TT from the propulsion units 550 to maintain the air vehicle 100 airborne, i.e., to at least balance the weight W of the air vehicle 100 during hover, to allow the air vehicle 100 to accelerate and/or climb, or to decelerate and/or reduce altitude, while the wing system 300 is concurrently not generating any lift, or generating very little lift .
  • the roll axis R is nominally vertical, or angularly inclined to the vertical such that the vertical component of the aggregate forward thrust TT is still sufficient to maintain the air vehicle 100 airborne without aerodynamic lift assistance from the wing system 300, i.e., to enable balancing the weight W of the air vehicle 100 during hover, or to allow the air vehicle 100 to accelerate and/or climb, or to decelerate and/or reduce altitude, while the wing system 300 is concurrently not generating any lift, or generating very little lift.
  • the air vehicle 100 is able to maneuver in one or more of pitch, roll or yaw, by suitably and differentially controlling the magnitude of the respective thrust T generated by each of the propulsion units 550, as disclosed herein.
  • an altitude of the air vehicle 100 is maintained substantially constant over time.
  • this can include maintaining the air vehicle 100 hovering over a fixed area.
  • a respective first command 3010A is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude nominally equal to the weight W of the air vehicle 100.
  • this example of the method excludes generating a respective second command (corresponding to second command 2020) to provide differential thrusts between the propulsion units 550.
  • Changes in altitude are provided by selectively increasing or decreasing the aggregate forward thrust TT until the desired rate of climb is achieved, after which the aggregate forward thrust TT is balanced with the air vehicle weight W, followed by deceleration to eliminate climb at the desired altitude.
  • a respective first command 3010B is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude greater than the weight W of the air vehicle 100.
  • this example of the method excludes generating a respective second command (corresponding to second command 2020) to provide differential thrusts between the propulsion units 550.
  • the climb/acceleration vectored thrust mode can also be used for vertical lift-off of the air vehicle 100 from a launch site.
  • the air vehicle 100 can be held in a nominally vertical position (i.e., with the roll axis R nominally vertical), either manually or using a suitable cradle.
  • a respective first command 3010B is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude less than the weight W of the air vehicle 100.
  • this example of the method excludes generating a respective second command.
  • descent/deceleration vectored thrust mode can also be used for vertical landing of the air vehicle 100 at a landing site.
  • a respective first command 4010 is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude nominally equal to the weight W of the air vehicle 100.
  • each propulsion unit 550 responsive to the first command 4010, each propulsion unit 550 generates a respective basic propulsion unit thrust Tu that is nominally a quarter of the aggregate forward thrust TT. i.e.:
  • this example of the method includes generating a respective second command and sending the second command to the propulsion units 550 to execute the desired turning moment while still maintain the same level of aggregate forward thrust TT.
  • a second command 4020 A is generated for causing the set of top propulsion units to generate different thrust from the thrust generated by the set of bottom propulsion units.
  • the second command 4020A causes the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TA generated by each one of the starboard top propulsion unit 550ST and the port top propulsion unit 550PT is determined as follows:
  • the second command 4020A causes the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TB generated by each one of starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB is determined as follows:
  • the differential thrust between the two top propulsion units 550 and the two bottom propulsion units generates a nose down pitch turning moment Mp, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • AT will depend on how fast the turning moment is desired to be.
  • a reverse turning moment in pitch can then be applied when the desired pitch angle has been attained in order to maintain the desired pitch angle.
  • Such a reverse turning moment in pitch can be provided by generating an appropriate second command 4020A in which the thrust is increased in the two bottom propulsion units, and concurrently decreased in the two top propulsion units.
  • the thrust vector of the aggregate forward thrust TT is also rotated away from vertical.
  • the aggregate forward thrust TT needs to be increased (via the first command 4010) such that the vertical component of the aggregate forward thrust TT nominally equals the weight W. This maneuver will also result in the air vehicle moving in a lateral direction in view of the horizonal component of the aggregate forward thrust TT.
  • Providing a turning moment in pitch, nose up (with respect to the air vehicle 100), during hover and while generating an aggregate forward thrust TT is essentially the reverse of providing a nose-up pitch moment, and starts with the second command 4020A causing the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 4020A causing the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in pitch, nose up or nose down, during acceleration/climb, is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained greater than the weight W of the air vehicle 100.
  • Providing a turning moment in pitch, nose up or nose down, during deceleration/descent is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the weight W of the air vehicle 100.
  • a second command 4020B is generated for causing the set of starboard propulsion units 550 to generate different thrust from the thrust generated by the set of port propulsion units 550.
  • the second command 4020B causes the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust Tc generated by each one of the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB is determined as follows:
  • the second command 4020B causes the port top propulsion unit 550PB and the port bottom propulsion unit 550PB to each generate a decreased thrust - AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TD generated by each one of port top propulsion unit 550PB and the port bottom propulsion unit 550PB is determined as follows:
  • the differential thrust between the two starboard propulsion units 550 and the two port propulsion units generates a yaw turning moment MY in the port direction, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • AT will depend on how fast the turning moment is desired to be.
  • a reverse turning moment in yaw can then be applied when the desired yaw angle has been attained in order to maintain the desired yaw angle.
  • Such a reverse turning moment in yaw can be provided by generating an appropriate second command 4020B in which the thrust is increased in the two port propulsion units, and concurrently decreased in the two starboard propulsion units.
  • the thrust vector of the aggregate forward thrust TT is also rotated away from vertical.
  • the aggregate forward thrust TT is caused to be increased (via the first command 4010) such that the vertical component of the aggregate forward thrust TT nominally equals the weight W. This maneuver will also result in the air vehicle moving in a transverse direction in view of the horizonal component of the aggregate forward thrust TT.
  • Providing a turning moment in yaw in the starboard direction (with respect to the air vehicle 100), during hover and while generating an aggregate forward thrust TT, is essentially the reverse of providing a yaw moment in the port direction, and starts with the second command 4020B causing port top propulsion unit 550PB and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 4020B causing the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in yaw, in the port direction or in the starboard direction, during acceleration/climb, is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained greater than the weight W of the air vehicle 100.
  • Providing a turning moment in in the port direction or in the starboard direction, during deceleration/descent, is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the weight W of the air vehicle 100.
  • a second command 4020C is generated for causing one diagonally disposed set of propulsion units 550 to generate different thrust from the thrust generated by the other set of diagonally disposed propulsion units 550.
  • the second command 4020C causes the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TE generated by each one of the starboard top propulsion unit 550ST and the port top propulsion unit 550PT is determined as follows:
  • the second command 4020C causes the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TF generated by each one of the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT is determined as follows:
  • the differential thrust between the two groups of diagonally opposed propulsion units (the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB, versus, the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT) generates a counter-clockwise roll turning moment Mp, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • AT will depend on how fast the turning moment is desired to be.
  • a reverse turning moment in roll can then be applied when the desired roll angle has been attained in order to maintain the desired roll angle.
  • a reverse turning moment in roll can be provided by generating an appropriate second command 4020C in which the thrust is increased in the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT, and concurrently decreased in the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB.
  • Providing a turning moment in roll in the clockwise direction is essentially the reverse of providing a nose-up pitch moment, and starts with the second command 4020C causing the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 4020C causing the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB to each generate a decreased thrust - AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in roll, counter clockwise or clockwise, during acceleration/climb, is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained greater than the weight W of the air vehicle 100.
  • Providing a turning moment in roll, counter clockwise or clockwise, during deceleration/descent is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the weight W of the air vehicle 100.
  • the wing system 300 aerodynamically generates sufficient lift L to maintain the air vehicle 100 airborne, i.e., to balance the weight W of the air vehicle 100 during forward flight, to allow the air vehicle 100 to accelerate and/or climb, or to decelerate and/or reduce altitude, while the propulsion system 500 is concurrently not generating any vertical thrust, or generating very little vertical thrust.
  • the roll axis R is generally horizontal, or angularly inclined to the horizontal by an angle of attack a such that the aerodynamic lift L generated by the wing system 300 is still sufficient to maintain the air vehicle 100 airborne without requiring assistance from any vertical component of the aggregate forward thrust TT generated by the propulsion system 500, and the wings are not stalled.
  • the aerodynamic lift L generated by the wing system 300 enables balancing the weight W of the air vehicle 100 during forward flight, or allows the air vehicle 100 to accelerate and/or climb, or allows the air vehicle 100 to decelerate and/or reduce altitude, while the propulsion system 500 is concurrently not generating any significant vertical thrust.
  • the aggregate forward thrust TT balances the drag D generated by the air vehicle 100 during straight and level flight at constant velocity.
  • the air vehicle 100 is able to maneuver in one or more of pitch, roll or yaw, by suitably and differentially controlling the magnitude of the respective thrust T generated by each of the propulsion units 550, as disclosed herein.
  • a respective first command 5010A is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude nominally equal to the drag D generated by the air vehicle 100.
  • this example of the method excludes generating a respective second command 2020.
  • a respective first command 5010B is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude greater than the drag D generated by the air vehicle 100.
  • this example of the method excludes generating a respective second command 2020.
  • a respective first command 5010C is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude less than the drag D generated by the air vehicle 100.
  • this example of the method excludes generating a respective second command 2020.
  • a respective first command 6010 is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT having a magnitude nominally equal to the drag D generated by the air vehicle 100.
  • each propulsion unit 550 responsive to the first command 6010, each propulsion unit 550 generates a respective basic propulsion unit thrust Tu that is nominally a quarter of the aggregate forward thrust TT. i.e.:
  • this example of the method includes generating a respective second command and sending the second command to the propulsion units 550 to execute the desired turning moment while still maintain the same level of aggregate forward thrust TT.
  • a second command 6020 A is generated for causing the set of top propulsion units to generate different thrust from the thrust generated by the set of bottom propulsion units.
  • the second command 6020A causes the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TA generated by each one of the starboard top propulsion unit 550ST and the port top propulsion unit 550PT is determined as follows:
  • the second command 2020 causes the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the differential thrust between the two top propulsion units 550 and the two bottom propulsion units generates a nose down pitch turning moment Mp, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • AT will depend on how fast the turning moment is desired to be.
  • a reverse turning moment in pitch can then be applied when the desired pitch angle has been attained in order to maintain the desired pitch angle.
  • Such a reverse turning moment in pitch can be provided by generating an appropriate second command 6020A in which the thrust is increased in the two bottom propulsion units, and concurrently decreased in the two top propulsion units.
  • the thrust vector of the aggregate forward thrust TT is also rotated away from horizontal, and the angle of attack a of the air vehicle 100 also changes, which can change the lift L generated by the wings.
  • Providing a turning moment in pitch, nose up (with respect to the air vehicle 100), during straight and level aerodynamic flight mode, (at a particular angle of attack a) and while generating an aggregate forward thrust TT is essentially the reverse of providing a nose-up pitch moment, and starts with the second command 6020A causing the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 6020A causing the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in pitch, nose up or nose down, during acceleration/climb is similar to that as disclosed herein regarding straight and level aerodynamic flight mode, (at a particular angle of attack a), mutatis mutandis, the main difference being that the respective aggregate forward thrust Tr is maintained greater than the drag D generated by the air vehicle 100.
  • Providing a turning moment in pitch, nose up or nose down, during deceleration/descent is similar to that as disclosed herein regarding straight and level aerodynamic flight mode, (at a particular angle of attack a), mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the drag D generated by the air vehicle 100.
  • a second command 6020B is generated for causing the set of starboard propulsion units 550 to generate different thrust from the thrust generated by the set of port propulsion units 550.
  • the second command 6020B causes the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust Tc generated by each one of the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB is determined as follows:
  • the second command 6020B causes the port top propulsion unit 550PB and the port bottom propulsion unit 550PB to each generate a decreased thrust - AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TD generated by each one of port top propulsion unit 550PB and the port bottom propulsion unit 550PB is determined as follows:
  • the differential thrust between the two starboard propulsion units 550 and the two port propulsion units generates a yaw turning moment MY in the port direction, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • AT will depend on how fast the turning moment is desired to be.
  • a reverse turning moment in yaw can then be applied when the desired yaw angle has been attained in order to maintain the desired yaw angle.
  • Such a reverse turning moment in yaw can be provided by generating an appropriate second command 2020 in which the thrust is increased in the two port propulsion units, and concurrently decreased in the two starboard propulsion units.
  • Providing a turning moment in yaw in the starboard direction (with respect to the air vehicle 100), during straight and level aerodynamic flight mode, (at a particular angle of attack a) and while generating an aggregate forward thrust TT, is essentially the reverse of providing a yaw moment in the port direction, and starts with the second command 6020B causing port top propulsion unit 550PB and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 6020B causing the starboard top propulsion unit 550ST and the starboard bottom propulsion unit 550SB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in yaw, in the port direction or in the starboard direction, during acceleration/climb, is similar to that as disclosed herein regarding straight and level aerodynamic flight mode, (at a particular angle of attack a), mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained greater than the drag D generated by the air vehicle 100.
  • Providing a turning moment in in the port direction or in the starboard direction, during deceleration/descent is similar to that as disclosed herein regarding straight and level aerodynamic flight mode, (at a particular angle of attack a), mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the drag D generated by the air vehicle 100.
  • a second command 6020C is generated for causing one diagonally disposed set of propulsion units 550 to generate different thrust from the thrust generated by the other set of diagonally disposed propulsion units 550.
  • the second command 6020C causes the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TE generated by each one of the starboard top propulsion unit 550ST and the port top propulsion unit 550PT is determined as follows:
  • the second command 6020C causes the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the total thrust TF generated by each one of the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT is determined as follows:
  • the differential thrust between the two groups of diagonally opposed propulsion units (the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB, versus, the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT) generates a counter-clockwise roll turning moment Mp, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT remains unchanged, since the total thrust is:
  • a reverse turning moment in roll can then be applied when the desired roll angle has been attained in order to maintain the desired roll angle.
  • Such a reverse turning moment in roll can be provided by generating an appropriate second command 6020C in which the thrust is increased in the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT, and concurrently decreased in the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB.
  • Providing a turning moment in roll in the clockwise direction (in the view seen in Fig. 2 with respect to the air vehicle 100), during straight and level aerodynamic flight mode, (at a particular angle of attack a) and while generating an aggregate forward thrust TT, is essentially the reverse of providing a nose-up pitch moment, and starts with the second command 6020C causing the starboard bottom propulsion unit 550SB and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu, and concurrently the second command 6020C causing the starboard top propulsion unit 550ST and the port bottom propulsion unit 550PB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • Providing a turning moment in roll, counter clockwise or clockwise, during acceleration/climb, is similar to that as disclosed herein regarding straight and level aerodynamic flight mode, (at a particular angle of attack a), mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained greater than the drag D generated by the air vehicle 100.
  • Providing a turning moment in roll, counter clockwise or clockwise, during deceleration/descent is similar to that as disclosed herein regarding hover, mutatis mutandis, the main difference being that the respective aggregate forward thrust TT is maintained less than the drag D generated by the air vehicle 100.
  • transition mode TRM the air vehicle 100 transitions between the vectored thrust mode VTM and the aerodynamic flight mode AFM. Depending on whether the air vehicle 100 is currently in vectored thrust mode VTM or in aerodynamic flight mode AFM, during transition mode TRM the air vehicle 100 can transition from the vectored thrust mode VTM to the aerodynamic flight mode AFM, or from the aerodynamic flight mode AFM to the vectored thrust mode VTM, respectively.
  • the transition mode TRM is carried out from the vectored thrust mode VTM to the aerodynamic flight mode AFM while concurrently increasing the aggregate forward thrust TT generated by the propulsion system of the air vehicle, from a baseline thrust level TTO to any desired aggregate forward thrust level T not exceed a maximum aggregate forward thrust level Ti max capable of being generated by the propulsion system of the air vehicle.
  • the baseline thrust level TTO corresponds to the level of aggregate forward thrust TT required to maintain hover, i.e., equal to the weight W of the air vehicle 500.
  • the maximum aggregate forward thrust level Timax corresponds to the maximum level of aggregate forward thrust TT that can be generated by the propulsion system 500.
  • the propulsion system is capable of provide an excess thrust ratio (with respect to weight W of the air vehicle 100
  • transition mode TRM the air vehicle 100 is operated such as to at least match the summation of lift L and/or the respective vertical component TTV of the aggregate thrust TT to the weight W of the air vehicle 100 during the transition.
  • the summation of lift L and/or the respective vertical component TTV of the aggregate thrust TT can be correspondingly less than the weight W of the air vehicle 100.
  • the summation of lift L and/or the respective vertical component TTV of the aggregate thrust TT can be correspondingly more than the weight W of the air vehicle 100.
  • the air vehicle 100 is operated in transition mode TRM to transit from the vectored thrust mode VTM to the aerodynamic flight mode AFM, at a nominally constant desired altitude DALT, and the air vehicle 100 is operated during transition mode TRM such as to nominally match the summation of lift L and the respective vertical component TTV of the aggregate thrust TT to the weight W of the air vehicle 100 during the transition.
  • transition mode TRM can be 100% matching, in which the aggregate thrust TT nominally equals the weight W of the air vehicle 100.
  • such matching can be within ⁇ N% of 100% matching, for example N can be +20% corresponding to 80% matching for example, in which the aggregate thrust TT is less the weight W of the air vehicle 100 by a corresponding proportion, for example 20%; for example N can be -20% corresponding to 120% matching for example, in which the aggregate thrust TT is greater the weight W of the air vehicle 100 by a corresponding proportion, for example 20%.
  • the air vehicle 100 can commence flight by being held by a user or on a stand at a take-off site, with the roll axis R in a general vertical orientation, in which the nose 210 is facing in an upward direction.
  • the air vehicle 100 prior to carrying out the transition mode TRM, the air vehicle 100 is first operated in vectored thrust mode VTM, and the propulsion system 500 is operated to provide sufficient aggregate forward thrust TT to enable the air vehicle 100 to first hover at the take off site, and thus can be disengaged from the user or the stand. Then the aggregate forward thrust TT can be increased to enable the air vehicle 100 to climb to a desired altitude, for example as disclosed herein regarding vectored thrust mode VTM. At the desired altitude the propulsion units 550 are operated to reduce the aggregate forward thrust TT to match the weight W of the air vehicle 100, which can then hover in vectored thrust mode VTM. The air vehicle 100 can then be operated in transition mode TRM to thereby transition to aerodynamic flight mode AFM at nominally constant altitude.
  • VTM vectored thrust mode
  • AFM aerodynamic flight mode
  • the air vehicle 100 transitions from the vectored thrust mode VTM to the aerodynamic flight mode AFM, while concurrently the altitude of the air vehicle 100 is maintained nominally constant over time at least during such transition.
  • the altitude of the air vehicle 100 is maintained nominally constant over time at least during such transition.
  • hover is maintained or alternatively another desired level of matching is maintained between the aggregate forward thrust TT and the weight W of the air vehicle 100.
  • a respective first command 7010A is generated and sent to the propulsion system 500 such as to generate an aggregate forward thrust TT (thus, initially, in a general vertical direction) having a magnitude nominally matches the weight W of the air vehicle 100 at the desired level of matching, and at the desired altitude.
  • each propulsion unit 550 responsive to the first command 7010A, each propulsion unit 550 generates a respective basic propulsion unit thrust Tu that is nominally a quarter of the aggregate forward thrust TT. i.e.:
  • the aggregate forward thrust TT has nominally zero horizontal component, and vertical component TTV is nominally equal to the aggregate forward thrust TT.
  • a second command 7020A is generated for causing the set of top propulsion units to generate greater thrust than the thrust generated by the set of bottom propulsion units 550, to thereby execute a desired nose-down turning moment in pitch while hovering.
  • a modified first command 7010A' is generated to cause the propulsion system 500 to incrementally increase the aggregate forward thrust TT such as to maintain the same level of vertical component TTV of the aggregate forward thrust TT as in hover, and thus maintain altitude, when said matching is 100%.
  • the second command 7020A causes the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu. Concurrently, the second command 7020A also causes the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the thrust vector of the aggregate forward thrust TT correspondingly tilts away from vertical, and if the magnitude of the aggregate forward thrust TT is maintained, the resulting vertical component TTV of the aggregate forward thrust TT would begin to decrease while the horizontal component TTH of the aggregate forward thrust TT would begin to increase.
  • Such a decrease in the magnitude of vertical component TTV of the aggregate forward thrust TT would result in a loss of altitude since the weight W is no longer balanced by the vertical component TTV of the aggregate forward thrust TT.
  • the modified first command 7010A' compensates for the effect of the pitch angle 0 on the vertical component TTV, by causing the aggregate forward thrust TT generated by the propulsion units 550 to be correspondingly increased to compensate for the inclination of the thrust vector from the vertical due to the increasing pitching angle 0.
  • the aggregate forward thrust TT increases to maintain the vertical component TTV of the aggregate forward thrust TT constant and equal to the weight W of the air vehicle 100, such that:
  • the modified first command 7010A' is directed to causing each propulsion unit 550 to generate a respective unit thrust Tu, determined as follows:
  • the method 7000A thus also includes determining the pitch angle 0.
  • the air vehicle 100 can include an attitude sensor, for example as is known in the art, for example, that is operatively coupled to the controller 260 thereby providing direct input data on pitch angle.
  • an increasing corresponding horizontal component TTH of the increasing aggregate forward thrust TT (concurrent with increasing pitch angle 0) provides an increasing horizonal forward velocity to the air vehicle 100.
  • This step including generating a modified first command 7010A' and concurrently generating second command 7020A in this manner, is continued so long as the pitch angle 0 from vertical is still not sufficient to provide an angle of attack a for the air vehicle 100 and/or a sufficient forward horizontal velocity for the air vehicle 100, such as to thereby enable the wing system 300 to generate any significant lift L.
  • the pitch angle 0 from vertical is still not sufficient to provide an angle of attack a for the air vehicle 100 and/or a sufficient forward horizontal velocity for the air vehicle 100, such as to thereby enable the wing system 300 to generate any significant lift L.
  • the corresponding angles of attack a can be too high to enable significant aerodynamic lift to be generated, and/or, the forward velocity can be too low to enable significant aerodynamic lift to be generated.
  • the total thrust TA generated by each one of the starboard top propulsion unit 550ST and the port top propulsion unit 550PT is determined as follows:
  • the total thrust TB generated by each one of starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB is determined as follows:
  • the differential thrust between the two top propulsion units 550 and the two bottom propulsion units generates a nose down pitch turning moment Mp, in view of the respective moment arms about the center of gravity CG, while the aggregate thrust TT progressively increases as the pitch angle 0 increases, to maintain the vertical component TTV nominally constant and matching the weight W.
  • the pitch angle 0 continues to increase, the angle of attack a of the air vehicle 100 and concurrently the horizontal velocity of the air vehicle 100 also continue to increase, thereby enabling aerodynamic lift L to be generated by the wing system 300.
  • a further modified first command 7010A" is generated to cause the propulsion system 500 to reduce the level of vertical component TTV of the aggregate forward thrust TT, such that the summation of the vertical component TTV of the aggregate forward thrust TT and the aerodynamic lift L, at each corresponding pitch angle 0, remains constant and balances the weight W, and thus maintain altitude.
  • the air vehicle 100 can include suitable accelerometers, for example as is known in the art, operatively connected to the controller 260 that operate to provide indications to the controller 260 whether the air vehicle 100 is beginning to descend (in which case the vertical component TTV of the aggregate forward thrust Tris increased) or ascend (in which case the vertical component TTV of the aggregate forward thrust TT is decreased).
  • the further modified first command 7010A" causes the propulsion units 550 to provide a correspondingly decreasing level of aggregate forward thrust TT.
  • the further modified first command 7010A" is maintained at a level such that the horizontal component TTH of the aggregate forward thrust TT provides the desired velocity and/or acceleration in the horizontal direction.
  • the method 7000 A further includes the step of terminating the second command 7020 when a desired pitch angle 0 has been reached.
  • a pitch angle 0 can correspond to providing an angle of attack a for the air vehicle sufficient to enable the air vehicle to generate sufficient lift L such as to at least balance the weight W.
  • a pitch angle 0 can be about 90°, and the air vehicle roll axis R is nominally horizontal, and the corresponding angle of attack a for the air vehicle can be zero.
  • the air vehicle 100 is capable of generating sufficient aerodynamic lift L, sufficient to balance the weight W, and thus the air vehicle 100 can operate in aerodynamic flight mode AFM.
  • Transition from aerodynamic flight mode AFM to the vectored thrust mode VTM essentially corresponds to the reverse of the vectored thrust mode VTM to the aerodynamic flight mode AFM.
  • the air vehicle 100 is operated in transition mode TRM to transit from the vectored thrust mode VTM to the aerodynamic flight mode AFM, at nominally constant altitude, and the air vehicle 100 is operated during transition mode TRM such as to utilize its inertia and/or gravitational deceleration or acceleration to effectively support the weight W of the air vehicle 100 during the transition.
  • transition mode TRM such as to utilize its inertia and/or gravitational deceleration or acceleration to effectively support the weight W of the air vehicle 100 during the transition.
  • the air vehicle inertia and/or gravitational deceleration essentially prevent the air vehicle from losing height or descending below a predetermined altitude PALT during transition.
  • the air vehicle 100 can commence flight by being held by a user or on a stand at a take-off site, with the roll axis R in a general vertical orientation, in which the nose 210 is facing in an upward direction.
  • the air vehicle 100 prior to carrying out the transition mode TRM, the air vehicle 100 is first operated in vectored thrust mode VTM, and the propulsion system 500 is operated to provide sufficient aggregate forward thrust TT to enable the air vehicle 100 to first hover at the take off site, and thus can be disengaged from the user or the stand. Then the aggregate forward thrust TT can be increased quickly to a maximum thrust TM, greater than the weight W, to enable the air vehicle 100 to accelerate and climb quickly towards a desired altitude DALT, for example as disclosed herein regarding vectored thrust mode VTM.
  • the hovering step can optionally be omitted, in which case the air vehicle 100 accelerates rapidly and climbs as soon as disengaged from the user or the stand.
  • the propulsion units 550 are operated to quickly reduce the aggregate forward thrust TT to match the weight W of the air vehicle 100, and allow the air vehicle to decelerate under gravity within this vertical spacing VS. During such deceleration, the inertia of the air vehicle 100 allows the air vehicle 100 to continue climbing to the desired altitude DALT while decelerating.
  • the air vehicle 100 can then be operated in transition mode TRM to thereby transition to aerodynamic flight mode AFM at nominally constant altitude, which can be defined as being a range of altitude corresponding to or falling within this vertical spacing VS.
  • the air vehicle 100 transitions from the vectored thrust mode VTM to the aerodynamic flight mode AFM, while concurrently the altitude of the air vehicle 100 is maintained within the vertical spacing VS at least during such transition.
  • the upwards inertia of the air vehicle is sufficient to at least balance the weight W of the air vehicle 100, such as to prevent the air vehicle from losing height below the predetermined altitude PALT, regardless of the attitude of the air vehicle 100 in pitch.
  • each propulsion unit 550 responsive to a first command 7010B, each propulsion unit 550 generates a respective basic propulsion unit thrust Tu that is nominally a quarter of the aggregate forward thrust TT. i.e.:
  • the aggregate forward thrust TT has nominally zero horizontal component, and the aggregate forward thrust TT, and the aggregate forward thrust TT corresponds to maximum thrust TM which is sufficient to provide the air vehicle with fast acceleration rate.
  • the aggregate forward thrust TT can be the maximum thrust that can be generated by the propulsion system 500.
  • a modified first command 7010B' is generated in which each propulsion unit 550 generates a respective basic propulsion unit thrust Tu that is nominally a quarter of the aggregate forward thrust TT, and in which the aggregate forward thrust TT is reduced to equal the weight W of the air vehicle 100 (or to any other desired level of matching).
  • the propulsion system 500 further generates a turning moment in pitch, nose down, to transit the orientation of the air vehicle 100 from vertical to horizontal.
  • a second command 7020B is generated for causing the set of top propulsion units to generate greater thrust than the thrust generated by the set of bottom propulsion units 550, to thereby execute a desired nose-down turning moment in pitch while hovering.
  • the second command 7020B causes the starboard top propulsion unit 550ST and the port top propulsion unit 550PT to each generate an increased thrust +AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the second command 7020B also causes the starboard bottom propulsion unit 550SB and the port bottom propulsion unit 550PB to each generate a decreased thrust -AT (equal to one another) over the respective basic propulsion unit thrust Tu.
  • the level of increased thrust +AT and of decreased thrust -AT is maximized such that the air vehicle can complete the pitch maneuver while the air vehicle is still within the vertical spacing VS.
  • the thrust vector of the aggregate forward thrust TT correspondingly tilts away from vertical, and if the magnitude of the aggregate forward thrust TT is maintained, the resulting vertical component TTV of the aggregate forward thrust TT would begin to decrease while the horizontal component TTH of the aggregate forward thrust TT would begin to increase.
  • Such a decrease in the magnitude of vertical component TTV of the aggregate forward thrust TT would eventually result in a loss of altitude since the weight W is no longer balanced by the vertical component TTV of the aggregate forward thrust TT.
  • the upward momentum of the air vehicle maintains the air vehicle within the vertical spacing VS during the turning maneuver.
  • the angle of attack a of the air vehicle 100 and concurrently the horizontal velocity of the air vehicle 100 also continue to increase, thereby enabling aerodynamic lift L to be generated by the wing system 300.
  • a further modified first command 7010B" is generated to cause the propulsion system 500 to generate forward thrust such that the the horizontal component TTH of the aggregate forward thrust TT provides the desired velocity and/or acceleration in the horizontal direction.
  • the method 7000B further includes the step of terminating the second command 7020B when a desired pitch angle 0 has been reached.
  • a pitch angle 0 can correspond to providing an angle of attack a for the air vehicle sufficient to enable the air vehicle to generate sufficient lift L such as to at least balance the weight W.
  • a pitch angle 0 can be about 90°
  • the air vehicle roll axis R is nominally horizontal, and the corresponding angle of attack a for the air vehicle can be zero.
  • the air vehicle 100 is capable of generating sufficient aerodynamic lift L, sufficient to balance the weight W, and thus the air vehicle 100 can operate in aerodynamic flight mode AFM.
  • Transition from aerodynamic flight mode AFM to the vectored thrust mode VTM essentially corresponds to the reverse of the vectored thrust mode VTM to the aerodynamic flight mode AFM.
  • the air vehicle can be allowed to reach the apogee and as the air vehicle then begins to accelerate downwardly under gravity, and within the vertical space VS, the transition mode is implemented.
  • a method for landing an air vehicle wherein the air vehicle comprises a fuselage, a fixed wing arrangement and a propulsion system including a plurality of propulsion units each mounted to the wing system in fixed spatial relationship to the wing system with respect to the roll axis, wherein the air vehicle is configured for operating in vectored thrust flight mode, aerodynamic flight mode, and transition mode, and wherein the air vehicle comprises a fuselage portion aft of the wing arrangement.
  • the air vehicle can be the air vehicle 100 disclosed herein with reference to Fig. 1.
  • Such a method can include the following steps:
  • step (a) and step (b) the air vehicle is operated in vectored thrust mode to hover in close proximity to the human operator, so that the fuselage portion is reachable by the arm of the human operator. Thereafter, in step (c), the air vehicle can be grasped at the fuselage portion by the hand of the operator, which effectively corresponds to landing the air vehicle.
  • the thrust generated by propulsion system is reduced to zero, and the weight of the air vehicle is supported by the operator.
  • the air vehicle can then be shut down operationally, and can be lowered onto the ground or any suitable surface.

Landscapes

  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Remote Sensing (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)

Abstract

L'invention concerne un véhicule aérien qui comprend un fuselage définissant un axe de roulis de véhicule aérien, un agencement d'aile fixe dans une disposition spatiale fixe par rapport au fuselage, et un système de propulsion comportant au moins quatre unités de propulsion. Chaque unité de propulsion est montée par rapport au système d'aile dans une relation espacée latérale par rapport à l'axe de roulis, des unités de propulsion adjacentes étant espacées circonférentiellement les unes des autres. Chaque unité de propulsion est configurée pour générer une poussée le long d'un axe de vecteur de poussée respectif. Chaque axe de vecteur de poussée est dans une orientation spatiale inclinée fixe par rapport à l'axe de roulis de telle sorte que la poussée respective présente un composant de poussée non nul défini sur un plan orthogonal à l'axe de roulis. Chaque composant de poussée non nul comporte un bras de moment non nul respectif par rapport à l'axe de roulis de façon à fournir un moment de roulis respectif. L'invention concerne également des procédés de commande du fonctionnement d'un véhicule aérien.
PCT/IL2024/050522 2023-05-30 2024-05-28 Véhicule aérien Pending WO2024246895A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IL303322 2023-05-30
IL303322A IL303322A (en) 2023-05-30 2023-05-30 Aircraft

Publications (1)

Publication Number Publication Date
WO2024246895A1 true WO2024246895A1 (fr) 2024-12-05

Family

ID=93656806

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IL2024/050522 Pending WO2024246895A1 (fr) 2023-05-30 2024-05-28 Véhicule aérien

Country Status (2)

Country Link
IL (1) IL303322A (fr)
WO (1) WO2024246895A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119734822A (zh) * 2025-03-06 2025-04-01 西北工业大学 采用可折叠机翼的尾座式无尾布局两栖飞行器及设计方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160313742A1 (en) * 2013-12-13 2016-10-27 Sz, Dji Technology Co., Ltd. Methods for launching and landing an unmanned aerial vehicle
US20180002003A1 (en) * 2016-06-03 2018-01-04 Aerovironment, Inc. Vertical take-off and landing (vtol) winged air vehicle with complementary angled rotors
US20200172238A1 (en) * 2017-05-09 2020-06-04 ST Engineering Aerospace Ltd. Aerial vehicle

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160313742A1 (en) * 2013-12-13 2016-10-27 Sz, Dji Technology Co., Ltd. Methods for launching and landing an unmanned aerial vehicle
US20180002003A1 (en) * 2016-06-03 2018-01-04 Aerovironment, Inc. Vertical take-off and landing (vtol) winged air vehicle with complementary angled rotors
US20200172238A1 (en) * 2017-05-09 2020-06-04 ST Engineering Aerospace Ltd. Aerial vehicle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119734822A (zh) * 2025-03-06 2025-04-01 西北工业大学 采用可折叠机翼的尾座式无尾布局两栖飞行器及设计方法

Also Published As

Publication number Publication date
IL303322A (en) 2025-01-01

Similar Documents

Publication Publication Date Title
US20230303244A1 (en) High speed multi-rotor vertical takeoff and landing aircraft
US10717522B2 (en) Vertical takeoff and landing (VTOL) air vehicle
US8146854B2 (en) Dual rotor vertical takeoff and landing rotorcraft
EP3868660A1 (fr) Aéronef à décollage et à atterrissage verticaux (adav) et procédés associés
US9334049B1 (en) Single blade rotor system for use in a vertical takeoff and landing (VTOL) aircraft
US10648455B2 (en) Flying apparatus
US8602348B2 (en) Flying-wing aircraft
US20190071174A1 (en) Vertical take off and landing aircraft with four tilting wings and electric motors
US20120286102A1 (en) Remotely controlled vtol aircraft, control system for control of tailless aircraft, and system using same
WO2014193693A1 (fr) Aéronef à décollage et atterrissage verticaux à transition nulle
CN107264794B (zh) 一种可拆卸混合式驱动垂直起降无人机的控制方法
CN110466752B (zh) 一种倾转旋翼无人机的控制方法及倾转旋翼无人机
CN116034075A (zh) 一种垂直起降飞机，用于控制垂直起降飞机的方法和系统
CN110770121B (zh) 飞行器
WO2024246895A1 (fr) Véhicule aérien

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24814781

Country of ref document: EP

Kind code of ref document: A1