Aircraft

Abstract

[Problem] The present invention makes it possible to provide an aerial vehicle in which, during flight of the aerial vehicle, the influence of wind which hits the frame in a prescribed direction is reduced, and fuel efficiency and stability are improved. [Solution] An aerial vehicle according to the present invention comprises a flight part including a frame which is connected to a plurality of rotors that each include at least a propeller and a motor, wherein the frame has two or more types of cross-sectional shapes corresponding to the position thereof. The frame also includes a right frame and a left frame that extend side by side in the front-rear direction of the vehicle body. At least one of the right and left frames has a substantially airfoil-shaped part, the front edge of which is positioned toward the outside of the vehicle body with respect to the vertical center line of the frame, and the rear edge of which is positioned toward the inside of the vehicle body. The substantial airfoil shape is a target airfoil shape.

Description

Technical Field

[0001] The present invention relates to a flying object.

Background Art

[0002] In recent years, research and demonstration experiments have been carried out towards the practical application of services using flying objects such as drones and unmanned aerial vehicles (UAVs) (hereinafter collectively referred to as "flying objects"). In practical applications, improvements in flight duration, the size and weight of loadable objects (payload), stability, etc. are required.

[0003] When used for transporting goods, people, etc., unlike hobby and photography uses, it often flies in a certain direction for a long time. Flying objects (hereinafter collectively referred to as existing airframes) in which cylindrical pipes as shown in Fig. 33 are radially assembled and are widely distributed in the market do not consider the relative wind and it is difficult to improve flight efficiency.

[0004] In Patent Document 1, a flying object having a shape that improves fuel efficiency when the flying object cruises in the nose direction is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In Patent Document 1, a flying object is disclosed in which an airfoil-shaped main body is provided on a flying object capable of carrying a load, so that the drag force against the relative wind from the front of the flying object can be reduced, or lift can be generated by the main body by the relative wind from the nose direction during flight, and the fuel efficiency of the flying object can be improved.

[0007] As a result, the flying object can fly for a longer time compared to existing aircraft, and it is said that it is possible to expand the range of services such as home delivery and reduce the fuel consumption of the flying object.

[0008] However, the shape of the flying object disclosed in Patent Document 1 only considers the case when it receives wind from the front of the flying object. When the flying object flies outdoors or the like, it will receive various winds such as the wind received due to the forward movement of the flying object, the wind from the lateral direction of the flying object due to the environmental wind, and the wind generated by the propeller equipped on the own aircraft.

[0009] In a flying object in which reduction of resistance against various winds and flow rectification and the like are not considered, it cannot be said that the fuel efficiency and stability in outdoor flight are sufficient.

[0010] Therefore, an object of the present invention is to provide a flying object capable of further improving the fuel efficiency and stability of the flying object during cruising by optimizing the frame shape with respect to the relative wind from a predetermined direction.

Means for Solving the Problems

[0011] According to the present invention, there is provided a flying object including a flight unit including a frame to which a plurality of rotary wings including at least a propeller and a motor are connected, wherein the frame has at least two or more cross-sectional shapes corresponding to its position.

Effects of the Invention

[0012] According to the present invention, it is possible to provide a flying object that reduces the influence of wind in a predetermined direction hitting the frame during flight of the flying object and improves fuel efficiency and stability.

Brief Description of the Drawings

[0013]

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Embodiments for Carrying Out the Invention

[0014] The content of the embodiments of the present invention will be listed and described. The flying object according to the embodiments of the present invention has the following configuration. [Item 1] A flying object comprising a flight unit including a frame to which a plurality of rotary wings each including at least a propeller and a motor are connected, wherein the frame has at least two or more cross-sectional shapes according to its position, A flying object characterized by this. [Item 2] The frame includes a right frame and a left frame extending side by side in the front-rear direction of the airframe, wherein at least one of the right frame and the left frame has a substantially airfoil-shaped portion in which the leading edge is located outside the airframe and the trailing edge is located inside the airframe with respect to the vertical center line in the frame, The flying object according to Item 1, characterized by this. [Item 3] The substantially airfoil shape is a target airfoil shape, The flying object according to Item 2, characterized by this. [Item 4] The frame includes a right frame and a left frame extending side by side in the front-rear direction of the airframe, In at least one of the right frame and the left frame, a frame portion below at least the radius of rotation of the pull-type rotor has a substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and in other frame portions, it has a substantially airfoil-shaped portion with a leading edge positioned on the upper side of the fuselage and a trailing edge positioned on the lower side of the fuselage along the vertical center line of the frame. The aircraft according to item 1, characterized in that. [Item 5] The frame includes a right frame and a left frame extending side by side in the longitudinal direction of the fuselage. In at least one of the right frame and the left frame, a frame portion below at least the radius of rotation of the pull-type rotor has a substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and a frame portion above at least the radius of rotation of the push-type rotor has a substantially airfoil-shaped portion inclined in a direction to straighten the air flowing into the propeller. The aircraft according to item 1, characterized in that. [Item 6] The frame includes a right frame and a left frame extending side by side in the longitudinal direction of the fuselage. In at least one of the right frame and the left frame, a frame portion below at least the radius of rotation of the pull-type rotor has a substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and in other portions, it has a substantially airfoil-shaped portion inclined at an angle different from the above inclination, with a leading edge positioned outside the fuselage and a trailing edge positioned inside the fuselage with respect to the vertical center line of the frame. The aircraft according to item 1, characterized in that. [Item 7] The frame includes a front frame and a rear frame. The side area of the rear frame is wider than the side area of the front frame. The aircraft according to any one of items 1 to 6, characterized in that. [Item 8] The frame includes a frame portion positioned below the radius of rotation of the pull-type rotor. The frame portion is located in front of the front frame and has a wider lateral area than the rear frame. The flying object according to any one of Items 1 to 6, characterized in that...

[0015] <Details of the Embodiment According to the Present Invention> Hereinafter, a flying object according to an embodiment of the present invention will be described with reference to the drawings.

[0016] <Details of the First Embodiment>

[0017] As shown in FIG. 1, a flying object 100 according to an embodiment of the present invention includes a flight unit 20 including a plurality of rotor parts composed of at least a propeller 110 and a motor 111 for flying, and elements such as a frame 21 connecting the rotor parts and the like. It is desirable to mount energy (for example, a secondary battery, a fuel cell, fossil fuel, etc.) for operating them. The flying object can use a single-rotor aircraft or a fixed-wing aircraft. In particular, for delivery applications to private homes, it is desirable to use a VTOL aircraft capable of vertical takeoff and landing or a rotorcraft called a so-called multicopter having a plurality of rotors. By using an aircraft capable of vertical takeoff and landing, peripheral facilities such as a port for takeoff and landing can be miniaturized.

[0018] Note that the illustrated flying object 100 is drawn in a simplified manner for ease of explaining the structure of the present invention. For example, detailed configurations such as a control unit are not shown.

[0019] The flying object 100 has the direction of the arrow D in the figure (+Y direction) as the forward direction (details will be described later).

[0020] In the following description, terms may be used according to the following definitions. Front-rear direction: +Y direction and -Y direction, up-down direction (or vertical direction): +Z direction and -Z direction, left-right direction (or horizontal direction): +X direction and -X direction, traveling direction (front): +Y direction, backward direction (rear): -Y direction, ascending direction (upward): +Z direction, descending direction (downward): -Z direction

[0021] The propeller 110 rotates upon receiving the output from the motor 111. When the propeller 110 rotates, a propulsive force is generated to cause the aircraft 100 to take off from the departure point, move, and land at the destination. Note that the propeller 110 can rotate in the right direction, stop, and rotate in the left direction.

[0022] The propeller 110 included in the aircraft of the present invention has one or more blades. Any number of blades (for example, 1, 2, 3, 4, or more blades) may be used. Also, the shape of the blade can be any shape such as a flat shape, a bent shape, a twisted shape, a tapered shape, or a combination thereof. Note that the shape of the blade can be changed (for example, expanded and contracted, folded, bent, etc.). The blade may be symmetric (having the same upper and lower surfaces) or asymmetric (having different-shaped upper and lower surfaces). The blade can be formed into a geometric shape suitable for generating dynamic aerodynamic forces (for example, lift, thrust) when the blade is moved through the air. The geometric shape of the blade can be appropriately selected to optimize the dynamic aerodynamic characteristics of the blade, such as increasing lift and thrust and reducing drag.

[0023] Also, the propeller included in the aircraft of the present invention can be a fixed pitch, a variable pitch, or a combination of a fixed pitch and a variable pitch, but is not limited thereto.

[0024] The motor 111 causes the propeller 110 to rotate. For example, the drive unit can include an electric motor or an engine, etc. The blade can be driven by the motor and rotates around the rotation axis of the motor (for example, the long axis of the motor).

[0025] The blades can all rotate in the same direction or independently. Some of the blades rotate in one direction and the other blades rotate in the other direction. The blades can all rotate at the same rotation speed or at different rotation speeds. The rotation speed can be determined automatically or manually based on the dimensions of the moving body (e.g., size, weight) and the control state (speed, moving direction, etc.).

[0026] The flying object 100 determines the rotation speed of each motor and the flying angle according to the wind speed and wind direction by means of a flight controller, propellers, etc. Thereby, the flying object can perform movements such as ascending and descending, accelerating and decelerating, and changing direction.

[0027] The flying object 100 can perform autonomous flight according to routes or rules set in advance or during flight, or flight by means of piloting using propellers.

[0028] The above-mentioned flying object 100 has the functional blocks shown in FIG. 6. Note that the functional blocks in FIG. 6 are the minimum reference configuration. The flight controller is a so-called processing unit. The processing unit can have one or more processors such as a programmable processor (e.g., a central processing unit (CPU)). The processing unit has a memory (not shown) and can access the memory. The memory stores logic, code, and / or program instructions that can be executed by the processing unit to perform one or more steps. The memory may include a separable medium or an external storage device such as an SD card or a random access memory (RAM). Data acquired from cameras and sensors may be directly transmitted to and stored in the memory. For example, still image and video data captured by a camera or the like are recorded in the built-in memory or the external memory.

[0029] The processing unit includes a control module configured to control the state of the rotary-wing aircraft. For example, the control module has six degrees of freedom (translational motion x, y, and z, and rotational motion θ x 、θy and θ z controls the propulsion mechanism (such as a motor) of the rotary-wing aircraft to adjust the spatial arrangement, speed, and / or acceleration of the rotary-wing aircraft having )]. The control module can control one or more of the mounting part and the states of the sensors.

[0030] The processing unit is communicable with a transceiver configured to transmit and / or receive data from one or more external devices (such as a terminal, a display device, or another remote controller). The transceiver can use any suitable communication means such as wired communication or wireless communication. For example, the transceiver can utilize one or more of a local area network (LAN), a wide area network (WAN), infrared, wireless, WiFi, a point-to-point (P2P) network, a telecommunications network, cloud communication, etc. The transceiver can transmit and / or receive one or more of the data acquired by the sensors, the processing results generated by the processing unit, predetermined control data, user commands from a terminal or a remote controller, etc.

[0031] The sensors according to the present embodiment may include an inertial sensor (an acceleration sensor, a gyro sensor), a GPS sensor, a proximity sensor (such as a lidar), or a vision / image sensor (such as a camera).

[0032] As shown in FIGS. 2-4, the flight unit 20 included in the flying object 100 in the embodiment of the present invention faces the traveling direction during traveling and has a posture tilted forward compared to the hovering state. The tilted rotary wing generates lift upward and thrust in the traveling direction, whereby the flying object 100 moves forward.

[0033] The aircraft 100 may be provided with a mounting section 30 that can fly while holding luggage, people, work sensors, robots, etc. (hereinafter collectively referred to as mounted objects) to be transported to a destination. The mounting section 30 may be fixedly connected to the flight section 20, or may be connected so as to be independently displaceable via a connection section such as a rotating shaft or a gimbal having one or more degrees of freedom, so that the object can be maintained in a predetermined posture (for example, horizontal) regardless of the posture of the aircraft 100.

[0034] Well-known flight section shapes of aircraft generally include a radial frame as shown in FIG. 33, a ladder-shaped frame as shown in FIG. 1, a monocoque frame as shown in FIG. 32, etc. For the radial frame and the ladder-shaped frame, carbon pipes or metal pipes with a circular or square cross-sectional shape of the frame are used. Since the resistance of the frame hardly changes regardless of the direction in which the aircraft travels, the radial frame is considered suitable for use in shooting applications or hobby applications where the traveling direction is not specified.

[0035] However, the frame 21 of the flight section 20 provided in the aircraft according to the present invention is specialized in a specific direction (for example, the nose direction) with a long usage time in applications such as transportation of people and objects and inspection, etc., to improve flight efficiency, and then to improve the efficiency in other directions (for example, the left and right directions). Therefore, it is more desirable to use a ladder-shaped frame or a monocoque frame instead of a radial frame.

[0036] The frame and the mounting section constituting the aircraft 100 are configured to include a material having a strength capable of withstanding flight and takeoff / landing. For example, resin, FRP, etc. are suitable as constituent materials of the aircraft because they are rigid and lightweight. Also, when using metal, by using those with a low specific gravity such as aluminum and magnesium, it is possible to prevent weight increase while improving strength.

[0037] In addition, the motor mount 23, the frame 21, etc. provided in the flight unit 20 may be configured by connecting them as separate parts, or may be integrally formed. By integrating the parts, it becomes possible to smooth the joints of the respective parts, so that reduction of drag and improvement of fuel efficiency can be expected.

[0038] The flying object 100 may be provided with landing legs 40. Further, in order to reduce the impact on the flying object when the landing legs are installed, the landing legs 40 may further be provided with shock absorption devices such as dampers.

[0039] The frame 21 provided in the flying object 100 is configured to have at least two or more cross-sectional shapes in order to reduce the influence of the wind received by each during the cruise of the flying object 100.

[0040] For example, in FIG. 3, when receiving the wind from the right side in the traveling direction as viewed from the flying object (hereinafter collectively referred to as the wind from the right), the right frame 21b is most affected. For example, at this time, the cross-sectional shape of the right frame 21b may be a substantially airfoil shape. When the outer side of the flying object (outside the fuselage) in the left-right direction (for example, with respect to the vertical center line in each frame) is the leading edge of the substantially airfoil shape and the inner side of the flying object (inside the fuselage) is the trailing edge of the substantially airfoil shape, the drag against the wind from the right can be reduced. The so-called substantially airfoil shape here is a shape having the same characteristics as the target wing, in which the thickness increases starting from the leading edge and decreases from a predetermined position toward the trailing edge, but is not limited to this. The shape may be such that the upper surface of the substantially airfoil shape bulges less than the lower surface (so-called inverted airfoil shape), or the lower surface bulges less than the upper surface (so-called airfoil shape). Thereby, when receiving wind from the direction of the leading edge, the drag is reduced compared to a frame having a circular cross-sectional shape. Also, the substantially airfoil in the present invention mainly aims to take a shape that efficiently reduces drag, and may have a different shape from a wing mainly aimed at generating lift. For example, it may be an inverted airfoil shape.

[0041] When receiving wind from the right, the wind is attenuated by the right frame 21b and the main body, and the wind from the right hitting the left frame 21a becomes weaker. Therefore, it is desirable for the left frame 21a to have a shape for reducing the resistance against the wind from the left side (hereinafter collectively referred to as the wind from the left) as viewed from the flying object, rather than the wind from the right. Note that the cross-sectional shape of each frame may be any shape for the purpose of reducing resistance and streamlining. More preferably, it is a substantially airfoil shape, but it may be a shape such as an elliptical shape or a trapezoidal shape in which resistance reduction and streamlining are performed against the wind received from one or more specific directions.

[0042] The cross-sectional shapes of the right frame 21b and the left frame 21a may be symmetric or asymmetric. For example, when the right frame is adapted to the wind from the right and the left frame is adapted to the wind from the left, the cross-sectional shapes of the respective left and right frames extending in the front-rear direction will be different. Further, if the effects imparted to the left and right frames are made symmetric, when looking at the cross-sectional shape at the same location of the frame in the front-rear direction, the shape will be symmetric.

[0043] When the propeller provided in the flying object rotates, a swirling air flow called the propeller wake occurs behind the propeller. As shown in FIGS. 1-5, when the rotary wing part provided in the flying object has a pull configuration, the part of each frame that is within the propeller wake will always be hit by wind during the rotation of the propeller. The propeller wake includes a lateral component depending on the rotation direction of the propeller. It is desirable to determine the motor rotation direction so that in the left-right direction, the propeller wake is directed from the outside to the inside of the flying object with respect to the right frame 21b and the left frame 21a respectively.

[0044] Since the shape for reducing resistance and streamlining has directivity, by bringing the directions of the natural wind and the propeller wake, which are the objects to which the effect is exerted, closer, it is possible to efficiently reduce resistance and streamline. When the rotation directions of all the motors provided in the flying object shown in FIG. 1 are reversed, the directions of the wind and the propeller wake in the left-right direction are reversed, and the right frame 21b and the left frame 21a may not be able to exert sufficient effects of reducing resistance and streamlining against the propeller wake.

[0045] That is, in a flying object having a frame shape that is effective against the wind from the outside in the left - right direction of the flying object, when the direction of the propeller wake generates a lateral wind from the inside to the outside in the left - right direction of the flying object, it becomes impossible to obtain sufficient drag reduction and wind rectification effects.

[0046] The crosswind due to the surrounding environment changes in the hitting direction such as directly sideways or diagonally downward of the aircraft body. However, the pull - type rotor part of the flying object, unless it has a special mechanism such as a tilt - rotor mechanism, the propeller wake is a swirling air flow and always hits the frame at a certain angle from the diagonally upward direction. The frame shape has an efficient cross - sectional shape in the direction of the propeller wake in the range where it is easily affected by the propeller wake, and has a cross - sectional shape independent of the wind direction of the propeller wake in the range where it is not affected by the propeller wake, so that it is possible to efficiently respond to the wind.

[0047] Examples of the cross - sectional shapes of the right frame 21b and the left frame 21a in the push - type rotor part are shown in FIG. 17, and examples of the cross - sectional shapes of the right frame 21b and the left frame 21a in the propeller wake of the pull - type rotor part are shown in FIG. 18. However, these shapes do not limit the cross - sectional shape, angle, etc. of the frame. The cross - sectional shape of each frame should be determined to be a suitable shape in terms of the operating environment, cost, etc. of the flying object 100, and the cross - sectional shape may be changed for each part and may be three, four or more types.

[0048] When a pull configuration and a push configuration are mixed as in the flying object shown in FIGS. 9 - 13, it is desirable that the frame near the rotor part of the pull configuration reduces the drag and rectifies the flow with respect to the propeller wake, and the frame near the rotor part of the push configuration rectifies the air flowing toward the propeller. Since the effects to be exerted by each are different, the cross - sectional shapes will also be different.

[0049] As shown in FIG. 12, when the frame 21 of the flying object in the cruising attitude has an increased front projected area compared to when hovering, for example, as shown in FIG. 16, by changing the cross-sectional shape for each part of the frame, an improvement in flight efficiency is expected. In the C-C' cut portion of the frame below the rotation radius of the pull-type rotor that is at least affected by the propeller wake, it has an angle adjusted to the rotation direction of the propeller wake. In the E-E' cut portion (and D-D' cut portion) of the frame above the rotation radius of the push-type rotor that is at least not affected by the propeller wake, by having an angle adjusted to the wind received from the front due to the forward movement of the flying object, an increase in the drag force caused by the frame during the cruising of the flying object is prevented, and the flight efficiency is improved.

[0050] As shown in FIG. 22, when the frame 21 of the flying object in the cruising attitude becomes closer to horizontal (the front projected area decreases) compared to when hovering, for example, as shown in FIG. 24, by changing the cross-sectional shape for each part of the frame, an improvement in flight efficiency is expected. In the C-C' cut portion, it has an angle adjusted to the rotation direction of the propeller wake. In the D-D' cut portion, it has an angle adjusted to the wind received from the side of the flying object by the ambient wind. In the E-E' cut portion, while adjusting to the wind received from the side of the flying object by the ambient wind, it has an angle for rectifying the air flowing into the propeller, thereby preventing an increase in the drag force caused by the frame during the cruising of the flying object and improving the flight efficiency.

[0051] As shown in FIGS. 19 - 23, when all the rotors of the flying object are in a push configuration, the frame 21 is provided at a position not affected by the propeller wake. Therefore, for the frame in the push configuration, there is no need to consider the effect on the propeller wake, and the drag force against the wind from the left and right directions hitting the flying object is reduced. It may also be used to rectify the air before it is drawn into the propeller.

[0052] As described above, the relative wind hitting the frame of the flying object during flight changes depending on conditions such as the presence or absence of the propeller wake due to the configuration of the rotor blades, the attitude of the frame during forward flight, the size and rotational speed of the propeller, and the cruising speed of the flying object. Therefore, the cross-sectional shape of the frame is determined to be a desirable shape in consideration of these conditions. <Details of the Second Embodiment> In the details of the second embodiment according to the present invention, since the components overlapping with those of the first embodiment perform the same operations, the description thereof will be omitted again.

[0053] The characteristic configuration of this embodiment is that when the shapes of the respective frames are made different, the side area in a side view of the front frame 21(f) and the rear frame 21(r) is compared, and the rear frame is configured to be wider. More specifically, when the frame 21 is composed of, for example, a round pipe or a square pipe, etc., the side area (i.e., the thickness in the vertical direction) when the frame is viewed from the side is wider in the rear frame portion than in the front frame portion. For example, only a predetermined position at the rear of the frame may be wider (more preferably, it may be widened to the extent of forming a surface), or it may gradually increase from the front of the frame to the rear, or increase stepwise at every predetermined length, but it is not limited to these. At this time, the thickness in the horizontal direction is not limited. Simply, the overall thickness in the horizontal direction may remain as it is and the thickness in the vertical direction may increase, or only a part of the thickness in the horizontal direction may extend in the vertical direction. Thereby, when the aircraft receives wind from the lateral direction, the rear of the aircraft is more strongly affected by the wind compared to the front, so that the nose of the aircraft is more likely to face upwind (so-called weathercock effect). In relation to the first embodiment, for example, in the cross-sectional shape of FIG. 16, since the C-C' cut surface is more inclined than the E-E' cut surface, the side area is wider in the E-E' cut surface, and the weathercock effect is exhibited even with this cross-sectional shape. For example, the weathercock effect may be made greater by making the E-E' cut surface longer in the vertical direction than the D-D' cut surface. Furthermore, even in the cross-sectional shape of FIG. 24, the weathercock effect is exhibited in the same manner. The C-C' cut surface has a smaller inclination than the E-E' cut surface, so the side area is large, but the position of the C-C' cut surface is within the rotation radius of the pull-type propeller, and the influence of the propeller wake is strong, and it is less affected by the crosswind. On the other hand, the position of the E-E' cut surface is a push-type propeller and there is no propeller wake, and it directly receives the influence of the crosswind. Therefore, since the side area is wider in the E-E' cut surface than in the D-D' cut surface, the weathercock effect is also exhibited.Thus, depending on the configuration of the propeller, it may be possible to be unaffected by crosswinds whether in the front or the rear. In this case, even if not all of the front frame portions are narrower than the rear side area, in the front-rear relationship other than the frame portions located below the radius of rotation of the pull-type rotor blades, the large rear side area produces a weather vane effect.

[0054] Thereby, particularly in a flying object as shown in Patent Document 1 that can improve flight efficiency when the flying object cruises in the nose direction, by providing a shape in which the nose of the flying object is likely to face the upwind direction, it becomes possible to make the flying object face the relative wind directly and improve the flight efficiency.

[0055] Also, as described above, by making the areas of the front frame 21(f) and the rear frame 21(r) different in side view, and further making the area of the rear frame 21(r) in side view wider than the area of the front frame 21(f) in side view, it is possible to assist in changing the nose direction by automatic control of the flying object, or to make the nose naturally face the upwind even without automatic control of the nose direction.

[0056] In addition, when making a specific part of the flying object likely to face the upwind, an improvement in flight efficiency can be expected not only in a flying object that mainly performs cruising in a specific direction, but also in a flying object that mainly operates in hovering. For example, in the case of a flying object with a shape that has the lowest drag when receiving wind from the nose direction, by naturally making the nose of the flying object face the upwind, it becomes possible to direct the nose of the flying object in a desired direction without performing yaw control.

[0057] The configurations of the flying object in each embodiment can be implemented in combination. It is desirable to appropriately consider a suitable configuration according to the cost in manufacturing the flying object and the environment and characteristics of the place where the flying object is operated.

[0058] The above-described embodiments are merely examples for facilitating the understanding of the present invention and are not intended to limit the interpretation of the present invention. It goes without saying that the present invention can be changed and improved without departing from its gist, and equivalents thereof are included in the present invention.

Explanation of Signs

[0059] 10 Load 20 Flying section 21 Frame 23 Motor mount 30 Mounting section 40 Landing leg 100 Aircraft 110a~110f Propeller 111a~111f Motor

Claims

1. An aircraft comprising a flight unit including a frame to which a plurality of rotary wings each including at least a propeller and a motor are connected, wherein the frame has at least two or more cross-sectional shapes according to its position, the frame includes a right frame and a left frame extending side by side in the longitudinal direction of the aircraft body, at least one of the right frame and the left frame has a first frame portion and a second frame portion other than the first frame portion, and the first frame portion below the rotation radius of at least a pull-type rotary wing has a first substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and in the second frame portion, the shape is different from that of the first substantially airfoil-shaped portion, characterized by an aircraft.

2. In at least one of the right frame and the left frame, the first frame portion below the rotation radius of at least a pull-type rotary wing has the first substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and in the second frame portion other than the first frame portion, there is a second substantially airfoil-shaped portion having a leading edge located on the upper side of the aircraft body and a trailing edge located on the lower side of the aircraft body along the vertical center line in the second frame portion, characterized by the aircraft according to Claim 1.

3. In at least one of the right frame and the left frame, the first frame portion below the rotation radius of at least a pull-type rotary wing has the first substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and the second frame portion above the rotation radius of at least a push-type rotary wing has a second substantially airfoil-shaped portion inclined in a direction for rectifying the air flowing into the propeller, characterized by the aircraft according to Claim 1.

4. In at least one of the right frame and the left frame, the first frame portion below the rotation radius of at least a pull-type rotary wing has the first substantially airfoil-shaped portion inclined in a direction corresponding to the rotation direction of the propeller, and in the second frame portion other than the first frame portion, there is an inclination at an angle different from the inclination, and there is a second substantially airfoil-shaped portion having a leading edge located outside the aircraft body and a trailing edge located inside the aircraft body with respect to the vertical center line in the second frame portion, characterized by the aircraft according to Claim 1.

5. The substantially airfoil shape is a target airfoil shape. The flying object according to any one of claims 1 to 4, characterized in that...

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