Patent ID: 12187421

DETAILED DESCRIPTION

The present system allows for a vertical take-off and landing (VTOL) aerial vehicle having four motors angled from vertical. Two sets of motors are on each end of a wing of the aerial vehicle, and the motors are separated from the ends of the wing by respective winglets. Two motors are on a top side, and two motors are on a bottom side of the aerial vehicle. The angling of the motors relative to a plane of the wing provides a lateral component of thrust for each motor. This thrust may apply a resulting torque additive to resulting torque created by rotating the rotors. Varying the thrust of each of the motors imparts a moment to urge the aerial vehicle to rotate about a center of mass of the aerial vehicle without changing the angles of the motors or their respective propeller blade pitches. The location the angled motors at the tips of the wing provides an extended distance from a centerline or center of mass of the aerial vehicle, which creates a longer moment arm such that smaller amounts of lateral thrust are needed to achieve a desired movement of the aerial vehicle. Utilizing a fixed pitch propeller reduces the need for a more expensive hub for a variable pitch propeller, increases the durability of the aerial vehicle, and reduces the weight of the aerial vehicle, while still providing the needed maneuverability of the aerial vehicle. The aerial vehicle may be autonomous and/or controlled by a remote user via a ground control system.

FIG.1depicts a perspective view of an exemplary vertical take-off and landing (VTOL) aerial vehicle100. The aerial vehicle100may be capable of vertical take-off and landing, hovering, vertical flight, maneuvering in a vertical orientation, transitioning between vertical and horizontal flight, and maneuvering in a horizontal orientation during forward flight. The aerial vehicle100may be controlled by an on-board control system that adjusts thrust to each of the motors132b,133b,142b,143band control surfaces122,124. The on-board control system may include a processor having addressable memory and may apply differential thrust of the motors132b,133b,142b,143bto apply both forces and torque to the aerial vehicle100.

The aerial vehicle100includes a fuselage110and a wing120extending from both sides of the fuselage110. The wing120may include control surfaces122,124positioned on either side of the fuselage110. In some embodiments, the wing120may not include any control surfaces to reduce weight and complexity. A top side or first side128of the wing120may be oriented upwards relative to the ground during horizontal flight. A bottom side or second side126of the wing120may be oriented downwards relative to the ground during horizontal flight. The wing120is positioned in and/or about a wing plane125. The wing plane125may be parallel to an x-y plane defined by the x-y-z coordinate system as shown inFIG.1, where the x-direction is towards a longitudinal axis of aerial vehicle100and the y-direction is towards a direction out along the wing120. The wing120may generally lie and/or align to the wing plane125. In some embodiments, the wing120may define or otherwise have a planform of the wing that defines a plane that the wing is positioned at least symmetrically about.

One or more sensors104may be disposed in the fuselage110of the aerial vehicle100on the second side126to capture data during horizontal forward flight. The sensor104may be a camera, and any images captured during flight of the aerial vehicle100may be stored and/or transmitted to an external device. The sensor104may be fixed or pivotable relative to the fuselage110of the aerial vehicle100. In some embodiments, the sensors104may be swapped based on the needs of a mission, such as replacing a LIDAR with an infrared camera for nighttime flights.

The aerial vehicle100is depicted in a vertical orientation, as it would be positioned on the ground prior to take-off or after landing. Landing gear103may maintain the aerial vehicle100in this vertical orientation. In some embodiments, the landing gear103may act as a vertical stabilizer during horizontal forward flight of the aerial vehicle100.

A first motor assembly130is disposed at a first end or tip of the wing120distal from the fuselage110. The first motor assembly130includes a pair of motor pods132,133including pod structures132a,133aand motors132b,133b; winglets138,139; and propellers134,135. A top port motor pod132may include a top port pod structure132asupporting a top port motor132b. A rotor or propeller134may be driven by the top port motor132bto provide thrust for the aerial vehicle100. The top port motor pod132may be disposed on the first side128of the wing120and may be separated from the first end of the wing120by a spacer or winglet138. The motor132bapplies a moment or torque on the propeller134to rotate it and in so doing applies an opposing moment or torque136on the aerial vehicle100. The opposing moment136acts to rotate or urge the aerial vehicle100to rotate about its center of mass102. The moment136may change in conjunction with the speed of the propeller134and as the propeller134is accelerated or decelerated. The propeller134may be a fixed or variable pitch propeller.

The motor pod132, the motor132b, and the propeller134may all be aligned to be angled up in the direction of the first side128of the wing120, up from the x-y plane in the negative z-direction, from the vertical while being within a plane of the winglet138, such that any force, and force components thereof, generated by the propeller134shall align, and/or be within, the plane of the winglet138, such that lateral forces to the plane of the winglet138are minimized or not generated. The alignment of the motor132band the propeller134may be a co-axial alignment of their respective axes of rotation.

The angle that the motor132band rotor134axes are from the vertical, x-direction, may vary from 5 to 35 degrees. In one exemplary embodiment, the angle may be about 10 degrees from vertical. The angle of the motor132band rotor134axes may be determined by the desired lateral force component needed to provide sufficient yaw in vertical flight and/or sufficient roll in horizontal flight, such as that necessary to overcome wind effects on the wing120. This angle may be minimized to maximize the vertical thrust component for vertical flight and the forward thrust component for horizontal flight.

The angling of the axis of rotation of the motor132band propeller134from the vertical, but aligned with the plane of the winglet138and/or with a plane perpendicular to the wing plane125, provides for a component of the thrust generated by the operation of the propeller134to be vertical, in the x-direction, and another component of the thrust to be perpendicular to the wing120, in the negative z-direction. This perpendicular component of the thrust may act upon a moment arm along the wing120to the center of mass102of the aerial vehicle100to impart a moment to cause, or at least urge, the aerial vehicle100to rotate about its vertical axis when the aerial vehicle100is in vertical flight, and to roll about the horizontal axis when the aircraft is in forward horizontal flight. In some embodiments, this component of thrust perpendicular to the wing120, or the negative z-direction, may also be applied in a position at the propeller134that is displaced a distance from the center of mass102of the aircraft100, such as to apply a moment to the aerial vehicle100to cause, or at least urge, the aerial vehicle100to pitch about its center of mass102. This pitching may cause, or at least facilitate, the transition of aerial vehicle100from vertical flight to horizontal flight, and from horizontal flight to vertical flight.

A bottom port motor pod133may include a bottom port pod structure133asupporting a bottom port motor133b. The bottom port motor133bis disposed on the second side126of the wing120opposing the top port motor132b. A rotor or propeller135may be driven by the bottom port motor133bto provide thrust for the aerial vehicle100. The bottom port motor pod133may be disposed on the second side126of the wing120and may be separated from the first end of the wing120by a spacer or winglet139.

The motor133bapplies a moment or torque on the propeller135to rotate it and in so doing applies an opposing moment or torque137on the aerial vehicle100. The opposing moment137acts to rotate or urge the aerial vehicle100to rotate about its center of mass102. The moment137may change in conjunction with the speed of the propeller135and as the propeller135is accelerated or decelerated. The propeller135may be a fixed or variable pitch propeller.

The motor pod133, the motor133b, and the propeller135may all be aligned to be angled down in the direction of the second side126of the wing120, down from the x-y plane in the z-direction, from the vertical while being within a plane of the winglet139, such that any force, and force components thereof, generated by the propeller135shall align, and/or be within, the plane of the winglet139, such that lateral forces to the plane of the winglet139are minimized or not generated. The alignment of the motor133band the propeller135may be a co-axial alignment of their respective axes of rotation.

The angle that the motor133band propeller135axes are from the vertical, x-direction, may vary from 5 to 35 degrees. In one exemplary embodiment, the angle may be about 10 degrees from vertical. The angle of the motor133band propeller135axes may be determined by the desired lateral force component needed to provide sufficient yaw in vertical flight and/or sufficient roll in horizontal flight, such as that necessary to overcome wind effects on the wing120. This angle may be minimized to maximize the vertical thrust component for vertical flight and the forward thrust component for horizontal flight.

The angling of the axis of rotation of the motor133band propeller135from the vertical, but aligned with the plane of the winglet139and/or with the plane perpendicular to the wing plane125, provides for a component of the thrust generated by the operation of the propeller135to be vertical, in the x-direction, and another component of the thrust to be perpendicular to the wing120, in the z-direction. This perpendicular component of the thrust may act upon a moment arm along the wing120to the center of mass102of the aerial vehicle100to impart a moment to cause, or at least urge, the aerial vehicle100to rotate about its vertical axis when the aerial vehicle100is in vertical flight, and to roll about the horizontal axis when the aircraft is in forward horizontal flight. In some embodiments, this component of thrust perpendicular to the wing120, or the z-direction, may also be applied in a position at the propeller135that is displaced a distance from the center of mass102of the aircraft100, such as to apply a moment to the aerial vehicle100to cause, or at least urge, the aerial vehicle100to pitch about its center of mass102. This pitching may cause, or at least facilitate, the transition of aerial vehicle100from vertical flight to horizontal flight, and from horizontal flight to vertical flight.

In some embodiments, the winglets138,139may be at least substantially symmetric about a first winglet plane perpendicular to the wing plane125. The first winglet plane may be substantially parallel to the x-z plane of the coordinate system shown inFIG.1. Vertical in the winglet plane may be defined by the intersection of the wing plane125and the plane of the winglets138,139, which can be the x-direction shown.

A second motor assembly140is disposed at a second end or tip of the wing120distal from the fuselage110and distal from the first motor assembly130. The second motor assembly140includes a pair of motor pods143,144including pod structures143a,144aand motors143b,144b; winglets148,149; and propellers144,145. A top starboard motor pod143may include a top starboard pod structure143asupporting a top starboard motor143b. A rotor or propeller145may be driven by the top starboard motor143bto provide thrust for the aerial vehicle100. The top starboard motor pod143may be disposed on the first side128of the wing120and may be separated from the second end of the wing120by a spacer or winglet149. The motor143bapplies a moment or torque on the propeller145to rotate it and in so doing applies an opposing moment or torque147on the aerial vehicle100. The opposing moment147acts to rotate or urge the aerial vehicle100to rotate about its center of mass102. The moment147may change in conjunction with the speed of the propeller145and as the propeller145is accelerated or decelerated. The propeller145may be a fixed or variable pitch propeller.

The motor pod143, the motor143b, and the propeller145may all be aligned to be angled up in the direction of the first side128of the wing120, up from the x-y plane in the negative z-direction, from the vertical while being within a plane of the winglet149, such that any force, and force components thereof, generated by the propeller147shall align, and/or be within, the plane of the winglet149, such that lateral forces to the plane of the winglet149are minimized or not generated. The alignment of the motor143band the propeller145may be a co-axial alignment of their respective axes of rotation.

The angle that the motor143band propeller145axes are from the vertical, x-direction, may vary from 5 to 35 degrees. In one exemplary embodiment, the angle may be about 10 degrees from vertical. The angle of the motor143band propeller145axes may be determined by the desired lateral force component needed to provide sufficient yaw in vertical flight and/or sufficient roll in horizontal flight, such as that necessary to overcome wind effects on the wing120. This angle may be minimized to maximize the vertical thrust component for vertical flight and the forward thrust component for horizontal flight.

The angling of the axis of rotation of the motor143band propeller145from the vertical, but aligned with the plane of the winglet149and/or with the plane perpendicular to the wing plane125, provides for a component of the thrust generated by the operation of the propeller145to be vertical, in the x-direction, and another component of the thrust to be perpendicular to the wing120, in the negative z-direction. This perpendicular component of the thrust may act upon a moment arm along the wing120to the center of mass102of the aerial vehicle100to impart a moment to cause, or at least urge, the aerial vehicle100to rotate about its vertical axis when the aerial vehicle100is in vertical flight, and to roll about the horizontal axis when the aircraft is in forward horizontal flight. In some embodiments, this component of thrust perpendicular to the wing120, or the negative z-direction, may also be applied in a position at the propeller145that is displaced a distance from the center of mass102of the aircraft100, such as to apply a moment to the aerial vehicle100to cause, or at least urge, the aerial vehicle100to pitch about its center of mass102. This pitching may cause, or at least facilitate, the transition of aerial vehicle100from vertical flight to horizontal flight, and from horizontal flight to vertical flight.

A bottom starboard motor pod142may include a bottom starboard pod structure142asupporting a bottom starboard motor142b. The bottom starboard motor142bis disposed on the second side126of the wing120opposing the top starboard motor143b. A rotor or propeller144may be driven by the bottom starboard motor142bto provide thrust for the aerial vehicle100. The bottom starboard motor pod142may be disposed on the second side126of the wing120and may be separated from the second end of the wing120by a spacer or winglet148.

The motor pod142, the motor142b, and the propeller144may all be aligned to be angled down in the direction of the second side126of the wing120, down from the x-y plane in the z-direction, from the vertical while being within a plane of the winglet148, such that any force, and force components thereof, generated by the propeller144shall align, and/or be within, the plane of the winglet148, such that lateral forces to the plane of the winglet148are minimized or not generated. The alignment of the motor142band the propeller144may be a co-axial alignment of their respective axes of rotation.

The angle that the motor142band propeller144axes are from the vertical, x-direction, may vary from 5 to 35 degrees. In one exemplary embodiment, the angle may be about 10 degrees from vertical. The angle of the motor142band propeller144axes may be determined by the desired lateral force component needed to provide sufficient yaw in vertical flight and/or sufficient roll in horizontal flight, such as that necessary to overcome wind effects on the wing120. This angle may be minimized to maximize the vertical thrust component for vertical flight and the forward thrust component for horizontal flight.

The angling of the axis of rotation of the motor142band propeller144from the vertical, but aligned with the plane of the winglet148and/or with the plane perpendicular to the wing plane125, provides for a component of the thrust generated by the operation of the propeller144to be vertical, in the x-direction, and another component of the thrust to be perpendicular to the wing120, in the z-direction. This perpendicular component of the thrust may act upon a moment arm along the wing120to the center of mass102of the aerial vehicle100to impart a moment to cause, or at least urge, the aerial vehicle100to rotate about its vertical axis when the aerial vehicle100is in vertical flight, and to roll about the horizontal axis when the aircraft is in forward horizontal flight. In some embodiments, this component of thrust perpendicular to the wing120, or the z-direction, may also be applied in a position at the propeller144that is displaced a distance from the center of mass102of the aircraft100, such as to apply a moment to the aerial vehicle100to cause, or at least urge, the aerial vehicle100to pitch about its center of mass102. This pitching may cause, or at least facilitate, the transition of aerial vehicle100from vertical flight to horizontal flight, and from horizontal flight to vertical flight.

In some embodiments, the winglets148,149may be at least substantially symmetric about a second winglet plane perpendicular to the wing plane125. The first winglet plane may be parallel to the second winglet plane. The second winglet plane may be substantially parallel to the x-z plane of the coordinate system shown inFIG.1. Vertical in the winglet plane may be defined by the intersection of the wing plane125and the plane of the winglets148,149, which can be the x-direction shown.

The motors132b,133b,142b,143boperate such that variations in the thrust, or rotation for fixed pitched rotors, and resulting torque or moment of pairs of the motors can create a resulting moment applied to the aerial vehicle100to move it in a controlled manner. Because of the angling off of the aircraft longitudinal centerline, vertical in hover and horizontal in forward horizontal flight, of each of the motors132b,133b,142b,143b, in addition to the moment imparted by the differential of the operation of the motors132b,133b,142b,143ba complementary force component is generated and applied to the aerial vehicle100to move it in the same manner.

Increasing thrust to the top two motors132b,143b, and decreasing thrust to the bottom two motors133b,142bin horizontal flight will cause the aerial vehicle100to pitch down. Decreasing thrust to the top two motors132b,143b, and increasing thrust to bottom two motors133b,142bin horizontal flight will cause the aerial vehicle100to pitch up. A differential between the thrust of the top two motors132b,143band the bottom two motors133b,142bmay be used to control the pitch of the aerial vehicle100during horizontal flight. In some embodiments, control surfaces122,124on the wing120may also be used to supplement pitch control of the aerial vehicle100. The separation of the top and bottom motors by their respective winglets is needed to create the pitch moment of the aerial vehicle100.

Increasing thrust to the top port motor132band bottom starboard motor142b, and decreasing thrust to the top starboard motor143band bottom port motor133bin horizontal flight will cause the aerial vehicle100to roll clockwise relative to a rear view of the aerial vehicle100. Decreasing thrust to top port motor132band bottom starboard motor142b, and increasing thrust to the top starboard motor143band bottom port motor133bin horizontal flight will cause the aerial vehicle100to roll counter-clockwise relative to a rear view of the aerial vehicle100. A differential between the thrust of the top port and bottom starboard motors and the top starboard and bottom port motors may be used to control roll of the aerial vehicle100during horizontal flight. In some embodiments, control surfaces122,124on the wing120may also be used to supplement roll control of the aerial vehicle100.

Increasing thrust to both port motors132b,133band decreasing thrust to both starboard motors142b,143bin horizontal flight will cause the aerial vehicle100to yaw towards starboard. Decreasing thrust to both port motors132b,133band increasing thrust to both starboard motors142b,143bin horizontal flight will cause the aerial vehicle100to yaw towards port. A differential between the thrust of the top and bottom starboard motors142b,143band the top and bottom port motors132b,133bmay be used to control yaw of the aerial vehicle100during horizontal flight.

In some embodiments, the motors132b,133b,142b,143bmay be detachable from their respective pod structures132a,133a,142a,143ato allow for quick replacement of a damaged or defective motor. In other embodiments, the motor assemblies130,140may be detachable from the tips of the wing120to allow for quick replacement of a damaged or defective motor, housing, or winglet, such as damage due to landing or during flight. The motors132b,133b,142b,143b, pod structures132a,133a,142a,143a, and/or motor assemblies130,140may be replaced with other components based on a desired flight mission, such as a greater thrust for increased wind conditions or greater efficiency for longer missions. In some embodiments, the propellers134,135,144,145may be disposed forward of a center of gravity102of the aerial vehicle100.

FIG.2depicts an exemplary VTOL aerial vehicle200transitioning from vertical flight to horizontal flight by varying the thrust produced by its motors. The aerial vehicle200is in a first position201on the ground ready for vertical take-off. A top motor210connected to a top propeller212is angled outward from vertical and away from a wing230. A bottom motor220connected to a bottom propeller222is angled outward from vertical and away from the wing230. The top motor210and bottom motor220are positioned at an end of the wing230of the aerial vehicle200and may be separated from the wing230by a winglet or spacer. Additional top and bottom motors and corresponding propellers may be present behind the top motor210and bottom motor220and positioned on the opposing end of the wing230, such as shown inFIG.1.

An on-board controller having a processor and addressable memory may send a signal to the motors to produce thrust needed for vertical take-off and subsequent adjustments to thrust during flight. Flight control may be anonymous, pre-programmed, and/or controlled by an external user at a ground control system. Top motors210create top thrust214, and bottom motors create bottom thrust224. During vertical take-off, the top thrust214and bottom thrust224may be substantially equal. The top thrust214and the bottom thrust224are depicted as angled based on the angles of the respective motors210,220and propellers212,222to have both a vertical and a lateral component.

The aerial vehicle200is in a second position203transitioning from vertical flight to horizontal flight. The aerial vehicle200pitches forward by increasing a top thrust216produced by the top motor210and decreasing a bottom thrust226produced by the bottom motor220. This thrust differential produces a net moment204about a center of mass202of the aerial vehicle200, which causes the aerial vehicle200to pitch forward. The component of the top thrust216in the lateral direction217is greater than the opposing lateral thrust219from the bottom thrust226, and the lateral thrust217adds to the lift236created by the wing230.

The aerial vehicle200is in a third position205in forward horizontal flight. The wing lift238is carrying the weight of the aerial vehicle200. As the top thrust218and bottom thrust228are adjusted, the aerial vehicle200may be pitched up or down. Adjusting thrust to the motors on the opposing end of the wing230of the aerial vehicle200may allow the aerial vehicle200to be yawed left or right by differential thrust between the right and left sides.

FIG.3Adepicts a perspective view of a schematic of an exemplary VTOL aerial vehicle300positioned vertically for vertical flight.FIG.3Bdepicts a side view of a schematic of the exemplary VTOL aerial vehicle300ofFIG.3A. The aerial vehicle300includes a center of mass316on a centerline310. The wing321,323and winglets338,339,348,349of the aerial vehicle300are represented by solid lines.

A bottom starboard motor pod332is depicted in dashed lines at the end of winglet338. The motor pod332has an axis of rotation positioned at an angle392from vertical in a plane X-Z1extending along and up and down winglets338,339and perpendicular to the wing321,323. The angle392may be in a range from about to 35 degrees. In some embodiments, the angle392may be at or about 10 degrees. The motor pod332may include a propeller334, which applies a counter-clockwise, as viewed from the front of the aerial vehicle300as inFIG.3A, torque or moment336to the aerial vehicle300. The thrust352produced by the propeller334has a lateral component354, which likewise imparts a torque or moment about the aerial vehicle300.

A top starboard motor pod333is depicted in dashed lines at the end of winglet339. The motor pod333has an axis of rotation positioned at an angle391from the vertical in the plane X-Z1extending along and up and down winglets338,339, and perpendicular to the wing321,323. The angle391may be in a range from about 5 to degrees. In some embodiments, the angle391may be at or about 10 degrees. The angle391of the top starboard motor pod333may be the same as the angle392of the bottom starboard motor pod332. The motor pod333may include a propeller335, which applies a clockwise, as viewed from the front of the aerial vehicle300, torque or moment337to the aerial vehicle300. The thrust351produced by the propeller335has a lateral component353, which likewise imparts a torque or moment about the aerial vehicle300. The moment created by lateral thrust354will be in the opposite direction of the moment created by the lateral thrust353. The lateral thrust354may be greater than lateral thrust353depending on respective thrusts352,351.

A top port motor pod342is depicted in dashed lines at the end of winglet348. The motor pod342has an axis of rotation positioned at an angle382from the vertical in a plane X-Z2extending along and up and down winglets348,349, and perpendicular to the wing321,323. The angle382may be in a range from about 5 to 35 degrees. In some embodiments, the angle382may be at or about 10 degrees. The angle382of the top port motor pod342may be the same as the angle391of the top starboard motor pod and/or an inverse of the angle392of the bottom starboard motor pod332. The motor pod342may include a propeller344, which applies a counter-clockwise, as viewed from the front of the aerial vehicle300, torque or moment346about the aerial vehicle300. The thrust362produced by the propeller344has a lateral component364, which likewise imparts a torque or moment about the aerial vehicle300.

A bottom port motor pod343is depicted in dashed lines at the end of winglet349. The motor pod343has an axis of rotation positioned at an angle381from the vertical in the plane X-Z2extending along and up and down winglets348,349, and perpendicular to the wing321,323. The angle381may be in a range from about 5 to degrees. In some embodiments, the angle381may be at or about 10 degrees. The angle381of the bottom port motor pod343may be the same as the angle392of the bottom starboard motor pod332, as an inverse of the angle382of the top port motor pod342, and/or as an inverse of the angle391of the top starboard motor pod. The motor pod343may include a propeller345, which applies a clockwise, as viewed from the front of the aerial vehicle300, torque or moment347about the aircraft300. The thrust361produced by the propeller345has a lateral component363, which likewise imparts a torque or moment about the aerial vehicle. The moment created by lateral thrust364will be in the opposite direction of the moment created by the lateral thrust363. The lateral thrust363may be greater than lateral thrust364depending on their respective thrusts361,362.

As shown inFIG.3B, the lateral thrust component364and lateral thrust component363are directed in the plane X-Z2in opposing directions, such that when their respective propellers344and345are producing the same thrust361,362, e.g. in hover or steady-state forward flight, that lateral thrust components363,364cancel each other out and don't provide a net moment or torque, about the y-axis, on to the aerial vehicle300. However, if either one of the thrust components361,362are larger, then the other then the lateral thrust components363,364shall also be different, resulting in a net force applied to moment arm390about the center of mass316to create a moment or torque393, which may cause the aerial vehicle300to pitch in the corresponding direction. As configured, this pitching moment is complementary to the pitching forces created by the differential thrust components in the x-direction created by the propellers344,345. Likewise, such is the case with the lateral thrust components353,354of the starboard motor pods and propellers as shown inFIG.3A.

FIG.4depicts a perspective view of a schematic of an exemplary VTOL aerial vehicle400where each motor is additionally angled towards a centerline of the aerial vehicle400. The propellers or rotors434,435,444,445are each positioned so that their thrust forces are orthogonal to a direct line back to a centerline410or a center of mass416of the aerial vehicle400, but none of the propellers434,435,444,445is parallel to another propeller434,435,444,445. The structure of the aerial vehicle400is represented by solid lines, including a wing423and winglets438,439,448,449. Lines401,402,403,404are each drawn between the respective motor pods and the center of mass416, and the center/thrust lines and axes of rotation are within planes parallel to the respective direct lines to the center of mass416.

A bottom starboard motor pod432is aligned to be angled from the vertical, x-direction, but orthogonal407to a line403directly to the centerline410or the center of mass416of the aerial vehicle400. The centerline of the motor pod432, the axes of rotation of the motor, and of the propeller434are positioned within a plane perpendicular to the line403. This positioning of the motor pod432will result in an inward, in the negative y-direction, tilt, cant, or angle from the vertical x-direction.

The top starboard motor pod433is aligned to be angled from the vertical, x-direction, but orthogonal408to a line404directly to the centerline410or the center of mass416of the aerial vehicle400. The centerline of the motor pod433, the axes of rotation its motor, and of the propeller435are positioned within a plane perpendicular to the line404. This positioning of the motor pod433will result in an inward, in the negative y-direction, tilt, cant, or angle from the vertical x-direction.

The top port motor pod442is aligned to be angled from the vertical, x-direction, but orthogonal405to a line401directly to the centerline410or the center of mass416of the aerial vehicle400. The centerline of the motor pod442, the axes of rotation its motor, and of the propeller444are positioned within a plane perpendicular to the line401. This positioning of the motor pod442will result in an inward, in the y-direction, tilt, cant, or angle from the vertical x-direction.

The bottom port motor pod443is aligned to be angled from the vertical, x-direction, but orthogonal406to a line402directly to the centerline410or the center of mass416of the aerial vehicle400. The centerline of the motor pod443, the axes of rotation its motor, and of the propeller445are positioned within a plane perpendicular to the line402. This positioning of the motor pod443will result in an inward, in the y-direction, tilt, cant, or angle from the vertical x-direction.

FIG.5Adepict a perspective view of an exemplary VTOL aerial vehicle500where each of the winglets538,539,548,549is disposed at an obtuse angle501,503,505,507from a plane of a wing520.FIG.5Bdepicts a front view of the exemplary VTOL aerial vehicle500ofFIG.5A. The winglets538,539,548,549are angled from a wing520or wing plane out towards each of the respective motor pods532,533,542,543. This angling of the winglets538,539,548,549assists in limiting or preventing the formation of wingtip vortices, which in-turn increases the performance and efficiency of the wing520. The winglets538,539,548,549may be positioned or otherwise formed at a non-zero angle of attack to counteract the effect of the wingtip vortices.

Portions of the airflow526over the wing520and about the fuselage521of the aerial vehicle500is represented with arrows. The airflow526ashows an airflow at or about, or otherwise substantially, zero angle of attack relative to the wing, such as would occur during forward horizontal or cruise flight. The airflow526bshows a (non-zero) angle of attack relative to the wing, such as during a pitch-up, transition to/from vertical flight, and/or slow flight. The aerial vehicle500creates some turbulence527aproximate the wing520as it travels through the air in horizontal flight with the airflow526and where the wing520typically is providing primary lift. The aerial vehicle500also creates turbulence528proximate the fuselage521during flight. At low or zero angles of attack of the airflow526a, such as during a cruise horizontal flight, the effects of turbulence527afrom the wing520may be relatively small and close to the wing520, as shown inFIG.5A. At higher angles of attack of the airflow526b, such as during a pitch up maneuver, the effects of turbulence527bfrom the wing520may be increased and displaced further out from the wing520, as shown inFIG.5A. With the airflow526aor526band with the turbulence527aor527bconditions, the winglets538,539,548,549position the motors and corresponding propellers in clean air regions522,523,524,525in front of and away from the turbulent air527coming off the wing520. The position of the motors532,533,542,543on the winglets538,539,548,549are also far enough away from the fuselage turbulence529regions such that the likelihood of the rotors or propellers on the motors being in a region of disturbed air is low. Further, even if the motors and corresponding propellers are in a region of turbulent or disturbed air, the strength of the turbulent or disturbed air is significantly reduced by the time it reaches the one or more impacted motors and corresponding propellers.

In contrast to the configuration of the aircraft500as shown inFIGS.5aand5b, the limited VTOL aerial vehicle700ofFIG.7which has its motors702,704positioned proximate to a fuselage710such that the motors and their respective rotors706and708are within the turbulence areas727caused by the airflow over and/or about the wings and the turbulence areas729caused by airflow over and/or about the fuselage710.

The angling of the motors reduces the shaft torque requirement. Reducing the shaft torque requirement significantly reduces the motor weight requirement and increases the horizontal propeller efficiency. The angling of the motors also keeps the propeller wash in line with the supporting pylons.

A ratio of wing520length to top winglet539,548length may be about 1.04:0.16. A ratio of wing520length to bottom winglet538,549length may be about 1.04:0.13. A ratio of top winglet length539,548to bottom winglet538,549length may be about 0.82:0.66. A ratio of top motor distance to wing520plane to bottom motor distance to wing520plane may be about 0.75:0.57. A ratio of wing520length to aerial vehicle500length may be about 7.1:3.7. A ratio of wing520length to propeller length may be about 5.2:1.3. A ratio of top motor distance to a plane aligned with a center of mass parallel to the wing520plane to bottom motor distance to the plane aligned with the center of mass parallel to the wing plane may be about 1:1. A ratio of the distance from top starboard motor to bottom port motor to the distance from bottom starboard motor to top port motor may be about 1:1.

An angle of a line connecting a bottom starboard motor to a top port motor may be about thirteen degrees from a plane parallel to a plane of the wing520. An angle of a line connecting a bottom port motor to a top starboard motor may be about thirteen degrees from a plane parallel to a plane of the wing520. The angle503,507of the bottom winglets538,549relative to the plane of the wing520may be about 120 degrees. The angle501,505of the top winglets539,548relative to the plane of the wing520may be about 115 degrees.

FIG.6Adepicts a front view of an exemplary propeller600for an exemplary VTOL aerial vehicle.FIG.6Bdepicts a top view of the exemplary propeller600ofFIG.6A.FIG.6Cdepicts a perspective view of the exemplary propeller600ofFIG.6A. The size of the propellers600used in the disclosed VTOL aerial vehicle is significantly smaller than existing quadcopters and VTOL aerial vehicles. The angling of the propellers600provides additive torque to a desired movement to increase the maneuverability of the VTOL aerial vehicle without requiring larger propellers that may be less efficient in forward horizontal flight. The propeller600is optimized to accommodate vertical flight yet maximize efficiency in horizontal flight. The planform, twist, and airfoils of the blades are tailored in a way that keeps horizontal flight efficiency near to that of a dedicated airplane propeller, while in vertical flight reduces the torque requirement on the motor, and maintains high design thrust margin.

FIG.7depicts a front view of a limited vertical take-off and landing (VTOL) aerial vehicle700having motors proximate a fuselage and angled in a plane parallel to a plane of a wing712,714. Two additional motors and corresponding propellers are present on the other side of the aerial vehicle700. The limited aerial vehicle700has two motors702,704and corresponding propellers706,708that are only angled in the plane parallel to the plane of the wing712,714, i.e., the angle of the motors702,704is perpendicular to the angle of the motors disclosed in the exemplary embodiments disclosed herein, such as inFIGS.1and5A-5B. The limited aerial vehicle700has motors702,704tilted in the direction of the plane along the wingspan rather than perpendicular to the wingspan. The angling of the motors702,704in the limited aerial vehicle700in this plane along the wingspan does not facilitate pitching with a moment in that direction. Further, the downwash of the propeller creates a counter moment and added down-force on the supporting pylon/fin when in vertical flight.

The limited VTOL aerial vehicle700also positions the motors702,704proximate to a fuselage710near a center of mass. During vertical flight, there is increased turbulence716from the fuselage710and/or wing712,714due to a crosswind. The crosswind in the longitudinal direction will cause ingestion of stalled air during transition to and from horizontal flight when control is most important. This increased turbulence716creates negative effects on the motors702,704disposed proximate to the fuselage710. By contrast, both sets of motors are disposed proximate wing tips of the exemplary aerial vehicle in the exemplary embodiments disclosed herein. Clean air regions718,720present near the wing tips of the exemplary embodiments disclosed herein allow for both a larger moment arm and reduced turbulence from crosswind. In the exemplary embodiments disclosed herein, the angling of the motors perpendicular to a wing plane and near wing tips does not induce an angle of attack on the support pylon/fin, and does not take away from the control authority produced by the vectored thrust, and reduces the power required to fly.

FIG.8depicts a perspective view of an exemplary VTOL aerial vehicle800landing801in a crosswind822. Crosswind is wind having a perpendicular component to the direction of travel of an aerial vehicle. Crosswinds may cause take-off and landing to be more difficult for aerial vehicles using a runway. The effects of crosswind may be enlarged by VTOL aerial vehicles during vertical take-off and landing due to the expanded surface area of the wing and fuselage exposed to such crosswinds. These surfaces may create areas of turbulent air that may negatively impact the operation and efficiency of the propellers. In some VTOL aerial vehicles, this may necessitate larger motors and/or propellers to counteract the effects of a crosswind.

The exemplary VTOL aerial vehicle800is landing801in the negative x-direction as shown in the axis ofFIG.8. A strong crosswind822in the z- and negative y-directions urges the aerial vehicle800away from its intended landing position. The crosswind822impacts port wing804, which causes an area of turbulent air824adjacent a bottom side of the port wing804. The crosswind822also impacts the fuselage802, which causes an area of turbulent air826adjacent a bottom side of the fuselage802. The crosswind822also impacts the starboard wing805, which causes an area of turbulent air828adjacent a bottom side of the starboard wing805.

The propellers814,816,818,820are each positioned away from the wing804,805by corresponding winglets806,808,810,812. While the winglets806,808,810,812are shown as perpendicular to the wing804,805, they may be positioned at an angle to the wing as inFIGS.5A-5B. Further, the propellers814,816,818,820are positioned above a leading edge of the wings804,805. Accordingly, the crosswind822may only create a region of turbulent air828affecting the bottom starboard propeller820, with the other propellers814,816,818being unaffected by the turbulent air generated off the wings804,805and/or the fuselage802. However, the strength of the turbulent or disturbed air828is significantly reduced and dissipated by the time it reaches the bottom starboard propeller820, because of the propeller820positioning away from the wing by winglet812and above the leading edge of the wing805. Propellers818,814,816are in clean air regions. Accordingly, the aerial vehicle800may use smaller motors and/or propellers as the effects of crosswind are countered by the positioning of the propellers814,816,818,820away from the wing804,805and fuselage802.

It is contemplated that various combinations and/or sub-combinations of the specific features and aspects of the above embodiments may be made and still fall within the scope of the invention. Accordingly, it should be understood that various features and aspects of the disclosed embodiments may be combined with or substituted for one another in order to form varying modes of the disclosed invention. Further, it is intended that the scope of the present invention is herein disclosed by way of examples and should not be limited by the particular disclosed embodiments described above.