JP2022150020A - Unmanned aircraft and control method thereof - Google Patents

Abstract

To provide an unmanned aircraft which is easily downsized and has high flight performance.SOLUTION: An unmanned aircraft having a kite wing 2 attached at a predetermined angle relative to an aircraft body 1 comprises: front edge pipes 23, 24 that are arranged in bilateral symmetry and turnably provided about a front side portion, relative to an airframe main shaft 10 of the kite wing 2; and propellers 121, 122, 131, 132 disposed on the airframe body 1. The kite wing 2 is flexible and supported by the front edge pipes 23, 24, and opened and closed according to turning of the front edge pipes 23, 24. At least one propeller is arranged to be positioned inside the kite wing 2, in plan view of the kite wing 2 in a fully open state.SELECTED DRAWING: Figure 2

Description

The present invention can be used for various purposes such as transportation of goods, surveying, aerial photography of scenery, investigation of disaster situations from the sky, inspection of bridges and building walls, spraying of pesticides and fertilizers, and security. , to an unmanned aerial vehicle and its control method.

Traditionally, small unmanned aerial vehicles have been used for a variety of applications such as those described above. Unmanned aerial vehicles include rotary wing type unmanned aerial vehicles called multicopters, helicopter types such as single rotors and tandem rotors, and fixed wing type unmanned aerial vehicles with main wings extending left and right from the fuselage. . These unmanned aerial vehicles are generally collectively called drones, and their spread has been remarkable in recent years, but each type has advantages and disadvantages.

For example, rotary wing type multicopters have disadvantages such as a relatively short cruising time and a small carrying weight, but they have advantages such as being able to take off and land without requiring a runway or the like. In addition, while fixed-wing unmanned aerial vehicles have the advantage of being able to travel longer distances, they require a large space such as a runway for takeoff and landing, and they also need to travel at a certain speed or higher during flight. The drawback is that it is difficult to fly at low speeds and hover (holding a stationary position in the air).

Also, a so-called Vertical Take-Off and Landing (VTOL) type unmanned aerial vehicle that enables vertical take-off and landing by combining a fixed wing type and a rotary wing type multicopter has appeared on the market. This type of unmanned aerial vehicle is as seen in Non-Patent Document 1 or Non-Patent Document 2, etc., and operates as a rotary-wing airframe during takeoff and landing, and as a fixed-wing airframe during horizontal flight. is the basis. For this reason, a long cruising range can be obtained without requiring a large space such as a runway for takeoff and landing.

Furthermore, as a type of unmanned aerial vehicle that is different from the usual fixed-wing type, there is an unmanned aerial vehicle called a kite-type, which has sail-like wings of a hang glider instead of the main wings. Compared to normal fixed-wing aircraft, this kite-type aircraft is capable of stable flight at low speeds and has a relatively long cruising time. In addition, although it has the characteristics of being able to take off and land on rough terrain, which is difficult for ordinary fixed-wing aircraft, and the possibility of wing damage is low, it requires a certain amount of runway.

Patent Document 1 (claim 1, paragraph 0004, etc.) describes such a kite-type small airplane as follows: "A film-like kite is provided above an airframe in which a head, a vertical stabilizer, and a horizontal stabilizer are connected by an elongated body. Attach the wing to the fuselage at the required angle, install a propeller between the kite wing and the fuselage. A radio-controlled small airplane has been proposed, which is detachably attached to the fuselage, has openings on the bottom and top of the head so as to communicate with the accommodation space, and attaches a detachable cover to the top opening. In addition, in this patent document 1 (paragraph 0014, etc.), the disclosed radio-controlled small airplane "uses a membrane-like kite wing as the main wing, so that it can generate a light weight and a large lift, and is stable. It is capable of level flight, stable flight at low speed, and easy maneuverability." According to Patent Document 1, the propeller installed "between the kite wings and the fuselage" generates the thrust of the airframe. and made it possible to fly.” The radio-controlled small airplane of Patent Document 1 achieves ascent and descent by rotation of the horizontal stabilizer, and turns left and right by rotation of the vertical stabilizer.

As described above, there are various forms of unmanned aerial vehicles, each of which has advantages and disadvantages. Therefore, by combining a plurality of different mechanisms, it is considered to eliminate the disadvantages while maintaining the advantages.

For example, Patent Literature 2 shows an unmanned aerial vehicle that combines a kite wing and three rotor blades. This unmanned aerial vehicle has "a configuration in which a kite wing and a control unit are added to a so-called multi-copter-like airframe with three or more rotor blades" (paragraph 0015, etc.), and is "a multi-copter with main wings. The purpose is to mitigate the effects of the wind during hovering and the airflow generated by its own rotor, and to expand the wind speed range that can be flown” (Paragraph 0013, etc.), and “The flexibility attached to the movable shaft of the aircraft It is possible to "control the shape and inclination of the kite wing, which has a sheet-like object as the main wing, and the kite wing with respect to the airframe" (paragraph 0014, etc.). In order to stabilize the lift generated by the kite wings and stabilize the output of the rotor blades, the three rotor blades are positioned not directly under the kite wings, but in a position where they do not overlap with the kite wings when viewed from above. In the figure, the structure is arranged outside the kite wings without overlapping with the kite wings (paragraph 0043, etc.). In the unmanned aerial vehicle of Patent Document 2, in controlling the shape of the kite wing, the position of the tip of the kite wing is slid along the central axis of the symmetrical kite wing, so that the left and right edges of the kite wing form each other. The angle and the angle of the central axis of the kite wing with respect to the airframe body are changed (paragraph 0045, etc.). In Patent Document 2, according to this aircraft, the lift generated by the kite wings is used to reduce the output of the rotor blades, and flight speed, flight time, and cruising distance can be improved compared to conventional multicopters. It is said that

Further, Patent Document 3 also discloses a moving device in which a propeller and a kite blade are combined. This is a "mobile device having a propeller for obtaining thrust and a kite section for obtaining buoyancy. When the device reaches a predetermined altitude, the kite section is deployed and the propeller rotation is It is disclosed that the kite part deploys by rotating the left and right edges called the leading rod around the central axis (claim 1, paragraph 0006, paragraph 0020). Such). This mobile device is intended to take pictures of the ground from the air for a long time by staying in the air within a certain range while flying (Paragraph 0015, etc.). According to this device, the electric power of the battery is effectively used, and it is possible to fly for a long time (paragraphs 0005, 0015, etc.).

Japanese Patent No. 2699263 JP 2019-26236 A JP 2019-127155 A

Kenzo Nonami: Rotorwing Robotics, Journal of the Robotics Society of Japan, Vol.34, No.2, pp.74-80 (2016) Takamitsu Urakubo: Research and Development of VTOL Drones - Toward the Realization of Next-Generation Drones, System/Control/Information, Vol.60, No.10, pp.437-442 (2016)

By the way, the unmanned aerial vehicle described in Patent Document 2 is an unmanned aerial vehicle that combines a kite wing and three rotary wings, as described above, and is capable of controlling the shape and inclination of the kite wing with respect to the airframe. However, in the unmanned aerial vehicle described in Patent Document 2, in controlling the shape of the kite wing, by sliding the position of the tip of the kite wing along the center axis of the symmetrical kite wing, the right and left edges of the kite wing A structure is used in which the angle between the wings and the angle of the center axis of the kite wings with respect to the airframe body are changed (Fig. 4, etc.). This not only complicates the mechanism, but also makes control more complicated by changing the shape and inclination of the kite wings, which changes the position of the center of gravity of the aircraft as a whole and the position of the center of lift that the aircraft receives during flight. There is an unavoidable problem. In addition, the three rotor blades are not placed directly under the kite wings, but are arranged outside the kite wings so that they do not overlap with the kite wings when viewed in plan (when viewed in plan and viewed within the projection plane). Therefore, the unmanned aerial vehicle described in Patent Document 2 has a problem that the size of the mechanism as a whole cannot be avoided.

Further, the unmanned aerial vehicle described in Patent Document 3 is a combination of a propeller and a kite wing, as described above. It deploys by rotating it around its axis. This structure has a problem that it is greatly affected by crosswinds when the kite wings are folded in two, and basically it is not in either the fully closed state when it is folded in two or the fully opened state when it is flattened. There is a problem that it is difficult to use.

As described above, when combining the respective advantages of the rotary wing type multi-copter and the fixed wing type, simply combining the two will result in mechanical waste, for example, and control problems. complication, or detract from other inherent advantages. Therefore, the main object of the present invention is to solve the drawbacks of the rotary wing type multicopter, such as vertical take-off and landing and low-speed flight, while maintaining its drawbacks of short cruising time and low transport weight. and

Furthermore, the present invention uses a compact and simple mechanism, can be controlled as easily as possible, is not easily affected by crosswinds when folded, and has the kite wings deployed from a fully closed state to a fully opened state. To provide an unmanned aerial vehicle capable of executing flight while continuously changing the effective wing area, for example, until Another object of the present invention is to provide an unmanned aerial vehicle capable of flying at various flight speeds.

In other words, the present invention has been made in view of the advantages and disadvantages of the above-mentioned various unmanned aerial vehicles, and its object is to maximize the cruising range, cruising time, or carrying weight, To provide an unmanned aerial vehicle which does not require a large space such as a runway for takeoff and landing, and which is capable of stable flight at low speed compared to fixed-wing aircraft. Another object of the present invention is to provide an unmanned aerial vehicle that can be easily miniaturized and has high flight performance.

The present invention relates to an unmanned aerial vehicle having a kite wing attached at a predetermined angle to the body of the aircraft,
an opening/closing frame member arranged symmetrically with respect to the central main axis of the kite wing and rotatable around a front portion;
at least three propellers provided on the fuselage body,
The kite wings are flexible and supported by the opening/closing frame member, and are opened and closed by rotation of the opening/closing frame member,
at least one propeller is arranged to be positioned inside the kite wing when the kite wing is in a fully open state and viewed from above;
It is an unmanned aerial vehicle characterized by

Further, the present invention provides a control method for an unmanned aerial vehicle having a kite wing attached at a predetermined angle to the airframe body,
The unmanned aerial vehicle is
an opening/closing frame member arranged symmetrically with respect to the central main axis of the kite wing and rotatable around a front portion;
at least three propellers provided on the fuselage body,
The kite wings are flexible and supported by the opening/closing frame member, and are opened and closed by rotation of the opening/closing frame member,
at least one of the propellers is arranged to be positioned inside the kite wing when the kite wing is in a fully open state and viewed from above;
capable of control in at least a climb mode, a level flight mode, and a descent mode;
in the climb mode, retracting the kite wings and generating thrust for ascent by the at least three propellers;
in the horizontal flight mode, deploying the kite wings;
generating thrust for descent by the at least three propellers in the descent mode;
A control method for an unmanned aerial vehicle characterized by:

According to the present invention, it is possible to provide an unmanned aerial vehicle that can be easily miniaturized and has high flight performance.

1 is a side view of an unmanned aerial vehicle according to a first embodiment of the present invention; FIG. 1 is a plan view of an unmanned aerial vehicle according to a first embodiment of the present invention; FIG. 1 is a front view of an unmanned aerial vehicle according to a first embodiment of the present invention; FIG. FIG. 2 is an explanatory diagram of the wing tip portion of the unmanned aerial vehicle according to the first embodiment of the present invention; (a) is an explanatory view showing the open state of the kite wing of the unmanned aerial vehicle according to the first embodiment of the present invention, and (b) is an explanatory view showing the closed state of the kite wing of the unmanned aerial vehicle. FIG. 2 is an explanatory diagram of the wing opening/closing drive mechanism of the unmanned aerial vehicle according to the first embodiment of the present invention; (a) is an explanatory view showing a modification of the opening/closing drive mechanism, and (b) is an explanatory view schematically showing the operation of the leading edge pipe and the leading edge pipe drive link in the opening/closing mechanism of (a). FIG. 4 is a side view of an unmanned aerial vehicle according to a second embodiment of the present invention; FIG. 2 is a plan view of an unmanned aerial vehicle according to a second embodiment of the present invention; Front view of an unmanned aerial vehicle according to a second embodiment of the present invention Control sequence diagram of the unmanned aerial vehicle according to the second embodiment of the present invention 4 is a graph showing the relationship between wing area and speed during flight of the unmanned aerial vehicle according to the first and second embodiments of the present invention; FIG. 4 is a block diagram of a control device for an unmanned aerial vehicle according to a second embodiment of the present invention;

An embodiment of the present invention will be described below based on the drawings. FIG. 1 is a side view of an unmanned aerial vehicle according to one embodiment (first embodiment) of the present invention, FIG. 2 is a plan view of the unmanned aerial vehicle according to the same first embodiment, and FIG. 3 is a front view of the same. . Here, in FIGS. 1 to 10 described below, straight lines are used as lead lines attached to each symbol. In addition, each lead line indicates the part corresponding to the code by an arrowhead or a black dot at one end.

This unmanned aerial vehicle can be applied to various uses such as distribution, inspection, surveying, photography, and disaster relief. The fuselage body 1 shown in FIGS. 1 to 3 and the like has a fuselage main shaft 10 (indicated by a dashed line) extending in the longitudinal direction, and is provided with a strut 11 . A central main shaft pipe 21 of the kite wing 2 is fixed to the upper end of the strut 11 so as to form a constant angle of attack (predetermined angle) with the airframe body 1 . Further, the airframe body 1 is supported on the ground by legs 19 instead of wheels. Note that the airframe body 1 may be supported by wheels (not shown).

Here, FIGS. 1 to 3 show directions by XYZ orthogonal coordinates. Of the coordinate axes, the direction of the X-axis coincides with the longitudinal direction of the body 1, and the front of the body 1 corresponds to the positive direction of the X-axis. Also, the direction of the Y-axis coincides with the left-right direction of the airframe body 1, and the right side of the airframe body 1 viewed from the rear to the front corresponds to the positive direction of the Y-axis. Furthermore, the direction of the Z-axis coincides with the vertical direction of the airframe body 1, and the lower side of the airframe body 1 corresponds to the positive direction of the Z-axis. The white circles in the coordinates in FIGS. 1 and 2 mean that the positive side is viewed from the negative side of the corresponding coordinates, and the black circles in the coordinates in FIG. Marks indicate looking from the positive side to the negative side of the corresponding coordinates.

FIG. 4 is an enlarged view of the tip of the central spindle pipe 21. A hinge plate 22 is fixed to the tip of the central spindle pipe 21. As shown in FIG. Around an axis perpendicular to the hinge plate 22, two front edge pipes (opening/closing frame members) 23 and 24 are rotatably attached around rotation axes 23s and 24s, respectively.

The kite wing 2 is made of a flexible material similar to the sail cloth used for sails of yachts, for example, and its wing shape is a so-called kite shape, that is, a generally linearly symmetrical orthogonal diagonal quadrilateral (Fig. 2 etc.). Two adjacent long side portions of the orthogonal diagonal quadrilateral are sewn into a bag-like shape, and the front edge pipes 23 and 24 are inserted into these bag-like portions to form the kite wing 2. The kite wings 2 are opened and closed by movement (rotation around the rotation shafts 23s and 24s).

Figure 5 shows the kite wing shape when the kite wing 2 is contracted and closed (Fig. 5(b)) and the kite wing shape when the kite wing 2 is expanded and opened (Fig. 5(a)). showing. The kite wing 2 can take any wing shape between these two states by turning the leading edge pipes 23 and 24 . In addition, by opening and closing the kite wings 2, the shape of the kite wings 2 in plan view (the shape viewed from the negative side to the positive side in the Z direction and viewed in the projection plane) changes, but the kite wings 2 are Maintains symmetrical shape regardless of open/close position. Therefore, the center of lift, which is the centroid position, is always located on the main axis 10 of the fuselage, and the moving distance in the longitudinal direction (X direction) of the fuselage is relatively small compared to the length of the leading edge pipes 23 and 24 . In this example, for example, when the vertical angle formed by the leading edge pipe 23 and the central main shaft pipe 21 when the kite wings 2 are fully opened is 60 degrees, the moving distance (moving distance of the lift center) is about the length of the pipe. 14%. In addition, since the kite wing 2 has its central main shaft pipe 21 fixed to the strut 11, the position of the center of gravity of the airframe body 1 as a whole does not change as the kite wing 2 opens and closes.

FIG. 6 is a view showing a portion related to the leading edge pipe drive mechanism, and using this, the mechanism for rotating the leading edge pipes 23 and 24 will be described. The leading edge pipe drive links 231, 232 have the same length and are attached at one end to each other so as to be rotatable about the rotation axis 23b. Similarly, the leading edge pipe drive links 241, 242 have the same length and are rotatably attached to each other at one end about the axis of rotation 24b.

A drive assembly 27 is fixed to the central spindle pipe 21, and gears 230, 240 that mesh with each other are rotatably mounted on the drive assembly 27. As shown in FIG. The other end of leading edge pipe drive link 231 is fixed to gear 230 and is rotatably attached to drive assembly 27 as well as central main shaft pipe 21 about axis of rotation 23c. The other end of the leading edge pipe drive link 232 is attached to the leading edge pipe 23 so as to be rotatable around the rotary shaft 23a. Similarly, the other end of leading edge pipe drive link 241 is fixed to gear 240 and is rotatably mounted relative to drive assembly 27 and center spindle pipe 21 about axis of rotation 24c. Further, the other end of the leading edge pipe drive link 242 is attached to the leading edge pipe 24 so as to be rotatable around the rotary shaft 24a.

Here, the positional relationship of the rotation shafts 23a, 23b, 23c, 24a, 24b, 24c and 23s, 24s described so far is as follows. The distance between the rotating shaft 23c and the rotating shaft 23s is the same as the distance between the rotating shaft 23a and the rotating shaft 23s, which is LL (not shown), for example. Also, the distance between the rotating shaft 24c and the rotating shaft 24s is the same as the distance between the rotating shaft 24a and the rotating shaft 24s, which is also LL. In addition, the rotating shafts 23a, 23b, 23c, 24a, 24b, 24c, and 23s, 24s are arranged in parallel in the Z direction, thereby forming two symmetrical planar four-link mechanisms. It is

Further, an electric motor (not shown) is disposed within the drive assembly 27, and its rotating shaft is fixed to the gear 230. By rotating the electric motor, the gears 230 and 240 rotate in opposite directions at the same angle. Rotate. Accordingly, by driving the electric motor, the leading edge pipe drive links 231, 232, 241, 242 are rotated, thereby driving the leading edge pipes 23, 24, resulting in FIG. The kite wings 2 are opened and closed as shown in (b).

6 only schematically shows the drive assembly 27, and the specific configuration such as the connecting positions of the gears 230, 240 and the leading edge pipe drive links 231, 241 is the leading edge pipe drive link 231, It can be determined appropriately so that 241 can smoothly follow the rotation of the gears 230 and 240 while rotating about the rotating shafts 23c and 24c.

Also, although the drive mechanism using a pair of gears 230 and 240 has been described here, instead of this, a mechanism using a link or a wire, etc., which has the same effect as the gears, may be used. As a modified example (modification), a slide-type mechanism is shown in FIG. 7(a). In this mechanism, a slide drive mechanism 28 is engaged with the central spindle pipe 21 so as to be capable of translational movement along the axial direction of the spindle.

Rotation shafts 23 e and 24 e are arranged symmetrically with respect to the central main shaft pipe 21 in the slide type drive mechanism 28 . Leading edge pipe drive links 233, 243 have the same length. Of these, the leading edge pipe drive link 233 has one end rotatable around a rotary shaft 23d fixed to the leading edge pipe 23 and the other end attached to a rotary shaft 23e on the slide type drive mechanism 28. is rotatably mounted around the

One end of the leading edge pipe drive link 243 is rotatable around the rotary shaft 24d fixed to the leading edge pipe 24, and the other end is rotatable around the rotary shaft 24e on the slide type drive mechanism 28. rotatably mounted on the Further, the rotation axes 23d, 23e, 24d, 24e, 23s, and 24s are arranged parallel to each other in the Z direction. and 23s, and the distances between the rotation axes 24d and 24s are the same. At this time, a motor (not shown) is used to translate the sliding drive mechanism 28 along the main axis of the central main shaft pipe 21, thereby moving the end positions of the leading edge pipe drive links 233 and 243 (black arrows A), thereby displacing the positions of the rotating shafts 23d and 24d, driving the leading edge pipes 23 and 24, respectively, and as a result, opening and closing the kite wings 2 as shown in FIG. 7(b). done. FIG. 7(b) synthetically shows the state of operation of the leading edge pipes 23, 24 and the leading edge pipe drive links 233, 243 in the slide type drive mechanism 28 of FIG. 7(a) in a schematic form.

Returning to FIGS. 1 to 3, the unmanned aerial vehicle has two arms 12 and 13 extending horizontally and perpendicularly to the main body axis 10 on both sides of the main body axis 10. It is fixed in a way that it sticks out. Propellers (rotary blades) 121, 122, 131, 132 driven by motors are fixed to the left and right ends of the arms 12, 13, respectively. Alternatively, it generates thrust (hereinafter also referred to as "propulsion") by rotating around a substantially vertical axis. That is, the flight mechanism employed in the unmanned aerial vehicle of this embodiment is a mechanism corresponding to a quadcopter drone having four propellers.

Here, in the following description, the reference numerals “121, 122, 131, 132” of the propellers are omitted as appropriate in order to avoid complicating the description. The term "propeller" is basically used to mean "propellers 121, 122, 131, 132". Supplement.

When the front edge pipes 23 and 24 are driven to open and close the kite wing 2, the tension of the kite wing 2, which is made of a canvas material similar to that of the sail of a yacht, changes and the sail cloth bends. When the body 1 is stopped, when the kite wings 2 are closed, there is a possibility that the sail cloth will hang downward from the leading edge pipes 23, 24 and the central main shaft pipe 21 due to gravity, and this is prevented. It is necessary.

Further, when the airframe body 1 is flying in a substantially horizontal direction, the kite wings 2 receive the air flow and generate lift. must be properly shaped.

Taking these things into consideration, one or more blade intermediate ribs 25 are provided between the central main shaft pipe 21 and the leading edge pipe 23, as indicated by the dashed line in FIG. One or more wing intermediate ribs 26 are provided intermediate the leading edge pipe 24 . These intermediate wing ribs 25, 26 may be fixed to the kite wing 2 by a method such as sewing. Alternatively, these blade intermediate ribs 25 and 26 can be provided between the central main shaft pipe 21 and the leading edge pipe 23 or between the central main shaft pipe 21 and the leading edge pipe 23 by using a means such as a link mechanism similar to that for driving the leading edge pipes 23 and 24. It may be configured (connected) intermediate the pipe 21 and the leading edge pipe 24 .

The intermediate wing ribs 25 and 26 have a function corresponding to a wing-shaped shaping member called a batten in, for example, a hang glider or the like. works. In this way, the shape of the intermediate blade ribs 25, 26 may be straight or non-linear. When the kite blade 2 is closed from the deployed state (when it changes to the contracted state), the wing intermediate ribs 25 and 26 are positioned above the plane containing both the central main shaft pipe 21 and the leading edge pipe 23, respectively. It is arranged to be at least partially displaced above a plane containing both the pipe 21 and the leading edge pipe 24 .

Further, the unmanned aerial vehicle includes a vertical stabilizer 15 for improving the stability of the fuselage body 1 in the lateral direction, that is, about the yaw axis, and a horizontal tail fin 15 for improving the stability of the fuselage body 1 in the vertical direction, that is, about the pitching axis. A tail 16 is provided. A rudder (reference numerals omitted) is attached to the vertical stabilizer 15, and an elevator (reference numerals omitted) is attached to the horizontal stabilizer 16, respectively.

Next, a procedure for flight by the unmanned aerial vehicle, that is, a control sequence will be described. First, for takeoff, the kite wings 2 are closed and folded as shown in FIG. 5(b). When the unmanned aerial vehicle is viewed from above as shown in FIG. 5(b), the kite wings 2 are arranged so that the four propellers are exposed to the outside of the kite wings 2 to block the airflow generated by the rotation of the propellers as much as possible. no state. Furthermore, the four propellers are rotated to generate lift and start to rise substantially vertically like a multi-copter. The control state at this time is a climb mode for raising the unmanned aerial vehicle.

In the state shown in FIG. 5(b), the entire propellers 121 and 122 arranged in front of the airframe body 1 are positioned outside the kite wings 2 and exposed. Furthermore, in the state shown in FIG. 5(b), most of the propellers 131 and 132 arranged behind the fuselage body 1 (here, about 80% or more of the area of the circle drawn by the tip trajectory C2 of the propellers 131 and 132) is exposed outside the kite wing 2.

After that, when the kite has ascended to an altitude at which it can fly substantially horizontally, as shown in FIG. In the state shown in FIG. 5(a), the propellers 131 and 132 arranged at the rear of the airframe body 1 are positioned inside the kite wing 2 and hidden when the kite wing 2 is viewed from above. Furthermore, in the state shown in FIG. 5(a), most of the propellers 121 and 122 placed in front of the fuselage body 1 (here, about half the area of the circle C1 drawn by the loci of the tips of the propellers 121 and 122) are It is located inside the kite wing 2. The control state at this time is a horizontal flight mode in which the unmanned aerial vehicle flies horizontally. Horizontal flight may be achieved by providing a propeller 170 separate from the propellers 121, 122, 131, 132 for generating horizontal thrust, or by using the four propellers provided by the quadcopter. you can go

After continuing horizontal flight and approaching a predetermined landing site, the kite wings 2 are contracted, folded and closed, and the four propellers rotate to generate thrust while starting to descend substantially vertically (control state to descent mode) and land. By performing flight based on the control sequence as described above, it is possible to fly without requiring a space such as a runway during takeoff and landing.

Here, when opening and closing the kite wings 2 during horizontal flight, the kite wings 2 are changed from the fully closed state (the most contracted state) to the fully opened state (the most extended state), or the kite wings 2 are changed from the fully opened state to the fully opened state. It is possible to change abruptly to However, if the state of the kite wing 2 is suddenly changed during flight, it is conceivable that the flight stability may be affected. Therefore, the state of the kite wings 2 may be changed in a plurality of stages between the fully closed state and the fully opened state, or may be changed continuously and smoothly. The kite wings 2 may be stopped in the middle of opening/closing (during opening/closing).

By performing such opening/closing control of the kite wings 2 during horizontal flight, it is possible to change the opening degree of the kite wings 2 based on flight stability. Furthermore, by changing the degree of opening of the kite wings 2 according to the flight speed of the unmanned aerial vehicle (by performing speed-dependent wing area control), it is possible to improve flight stability. Here, the opening degree of the kite wings 2 can be changed by adjusting the amount of rotation of the gears 230 and 240 in the drive assembly 27 (FIG. 6) described above and by adjusting the amount of sliding of the sliding drive mechanism 28. is.

Further, the flight stability of the unmanned aerial vehicle can also be ensured by changing (changing) the angle of attack of the kite wings 2 instead of the opening of the kite wings 2 . The angle of attack can be changed by changing the angle (opening) of an elevator provided at the rear end of the horizontal stabilizer 16 .

<Another form for carrying out the invention (second embodiment)>
As an extension of the embodiment (first embodiment) of the present invention described above, another embodiment (second embodiment) will be described with reference to FIGS. 8 to 10 and the like. The same reference numerals are given to the same parts as in the first embodiment, and the description thereof will be omitted as appropriate.

In the second embodiment, the four propellers (rotating blades) of the quadcopter section are rotated around the main axes of the two arms 12 and 13 to which the four propellers are attached, thereby rotating the propellers. A mechanism configuration that allows the axis to be changed between a vertical or approximately vertical direction and a horizontal or approximately horizontal direction, that is, a configuration that tilts the rotation shafts of the four propellers is adopted. In the unmanned aerial vehicle of the second embodiment, the four propellers face the vertical direction (Z direction) of the airframe body 1 as in the first embodiment, and the longitudinal direction (X direction) of the airframe body 1. It is possible to tilt between the posture facing the

In the second embodiment shown in FIGS. 8 to 10, etc., the four propellers of the quadcopter section can be tilted around the main axes of the arms 12 and 13, and the second embodiment shown in FIGS. It is the same as one embodiment. 8 to 10 when the rotating shafts of the four propellers are rotated substantially horizontally, whereas the shape shown in FIGS. 1 to 6, etc., respectively. In the following description, a mechanism for rotating the rotation shafts of the four propellers around the main shafts of the arms 12 and 13 is called a rotor blade tilt mechanism. A method of driving the tilt mechanism can be easily realized using a known technique by using an electric motor or the like, and the outline thereof will be described later.

Next, the procedure for flying the unmanned aerial vehicle of the second embodiment, that is, the control sequence will be described with reference to FIG. FIG. 11 schematically shows the operations of the propeller, the kite wing 2, and the tilt mechanism in the unmanned aerial vehicle according to the second embodiment, and the state of the unmanned aerial vehicle in a timing chart. The horizontal axis in FIG. 11 indicates time, and the vertical axis indicates the rotation and stoppage of the propeller, the opening and closing of the kite wings 2, and the operation state of the tilt mechanism (horizontal flight state or vertical flight state).

First, when taking off, the unmanned aerial vehicle maintains the rotation axes of the four propellers substantially vertically as shown in FIG. In the closed and folded state, the four propellers are rotated to generate lift and begin to ascend almost vertically like a multi-copter. The state of the unmanned aerial vehicle at this time is, for example, from a state of "stopping" on the ground to a state of "taking off", as shown from the left end in "State" at the bottom of FIG. The control state at this time is the climb mode for raising the unmanned aerial vehicle, as in the first embodiment described above.

After that, when the unmanned aerial vehicle has ascended to an altitude at which it can fly substantially horizontally, the tilt mechanism is driven to rotate the four propellers around the main axes of the arms 12 and 13, as shown in "Tilt" in FIG. to position the propeller's axis of rotation generally horizontally as shown in FIGS. 8-10. Along with this, the unmanned aerial vehicle deploys the kite wings 2 and transitions to horizontal flight. Therefore, horizontal flight can be performed using the four propellers, and there is no need to provide propellers for generating horizontal propulsion force separately from the propellers 121, 122, 131, and 132. None.

The state of the unmanned aerial vehicle at this time is the first transition mode, which is the transition mode when transitioning to level flight, and corresponds to the state of "transition (first transition)" in FIG. Also, the control state at this time is a state in which the transition from the first transition mode to the horizontal flight mode in which the unmanned aerial vehicle flies horizontally as in the first embodiment described above.

After continuing level flight and approaching a predetermined landing site, the kite wings 2 are contracted, folded and closed as shown in FIG. 11, "Kite wings". Then, the tilt mechanism is driven to rotate the four propellers around the main shafts of the arms 12 and 13, the rotation shafts of the four propellers are positioned substantially vertically again as shown in FIG. While generating thrust by rotating the four propellers, the aircraft starts to descend substantially vertically (changes the control state to the descending mode) and lands.

The state of the unmanned aerial vehicle at this time corresponds to the state from "transition (second transition)" to "landing" in the bottom "state" in FIG. The state of the unmanned aerial vehicle in this case is the second transition mode, which is the transition mode when shifting to the descent mode. Also, the control state at this time is a state of transition from the second transition mode to "landing".

By performing flight based on the control sequence described above, horizontal flight and vertical elevation are possible without installing a propeller dedicated to horizontal flight. It is possible to

Here, in FIG. 11, the control sequence is such that the kite wing 2 deploys after the rotation of the tilt mechanism is completed at takeoff. The timing of starting and ending the deployment operation does not necessarily have to be in the form shown in the time chart (sequence diagram) of FIG. For example, start rotating the tilt mechanism and start deploying the kite wings 2 when the tilt angle reaches a predetermined angle, or reverse this order (deploy the kite wings 2 and then start the tilt mechanism). start rotating), or operate both at the same time. Similarly, the timing of the operation of closing the kite wings 2 and the pivoting operation of the tilt mechanism during landing does not have to follow only the form shown in the time chart of FIG.

In the case of the first embodiment of the present invention (the embodiment shown in FIGS. 1 to 3, etc.), that is, when the tilt mechanism is not provided, for example, the timing for generating the horizontal propulsion force at the time of takeoff and the kite The same can be said about the timing of deploying the wings 2 (the second embodiment shown in FIGS. 8 to 10), and it is possible to select the appropriate control sequence.

Also, in the second embodiment, all four propellers are tilted, but this is not a limitation. may tilt only. In this case, for example, only the front propellers 121 and 122 are tilted so that the angle of attack changes as described in the first embodiment, and the propulsive force for horizontal flight of the airframe can be generated. By doing so, it becomes possible to effectively utilize the tilt mechanism. In addition, when changing the angle of attack of the kite wing 2, there is no need to rely on the elevator of the horizontal stabilizer 16. It is also possible to change the angle of attack by using both the propellers 121 and 122 and the elevator of the horizontal stabilizer 16 .

<Further aspects for carrying out the invention (relationship between wing area and speed)>
Next, in the configuration of the unmanned aerial vehicle of the first and second embodiments of the present invention and the control method of these unmanned aerial vehicles from takeoff to landing, the kite wing 2 during flight other than during takeoff and landing will be described. One aspect of the control method for opening/closing will be described with reference to FIG. 12 . Here, FIG. 12 plots the flight speed v on the horizontal axis and the wing area S on the vertical axis. The graph is based on the assumption that CL is constant. The lift coefficient CL varies depending on the elevation angle of the wing. The lift coefficient CL does not change even if it is changed, and the graph of the relationship between the flight speed v and the wing area S in FIG. 12 can be used.

As shown in this graph, based on the knowledge of fluid dynamics and aeronautical engineering, the larger the wing area in plan view, the greater the lift force received by the airframe body 1 during horizontal flight. The velocity increases approximately in proportion to its square. Therefore, by having the kite opening and closing mechanism as in the first embodiment and the second embodiment, the area of the wing is reduced correspondingly when the flight speed is desired to be increased, and when the flight speed is desired to be decreased, the Correspondingly, the area of the wing is increased and the effective area of the kite wing 2, which contributes to the generated lift, is changed to control the fluctuation of the lift acting on the airframe and to achieve stable flight at the required speed. It can be realized. This means that the kite wings 2 are closed during flight from a fully opened state to an appropriate degree of opening, and by reducing the wing area, the air resistance received by the wings is reduced. Compared to an unmanned aerial vehicle with kite wings, it can be said that control can be performed to achieve high-speed flight.

Next, the control device 50 applicable to the unmanned aircraft according to the first and second embodiments of the present invention described above will be described with reference to FIG. In FIG. 13, a straight arrow is used as a lead line attached to each symbol. Also, each leader line points to the corresponding block by having one end of the arrowhead reach the block. On the other hand, the one-way or two-way arrow representing the signal in FIG. 13 is distinguished from the leader line by the fact that the ends stop on the outline of the block and do not enter the block.

The control device 50 is mainly composed of a control computer 51 represented by a microprocessor or the like, and uses a wireless transmitter/receiver 52 to communicate flight-related commands with an operator on the ground, and control flight information such as the current flight position. Communication of status, transmission of images, and the like are performed.

Regarding the flight control of the unmanned aerial vehicle, the flight position is calculated based on the information obtained from the GPS receiver 53 and the information obtained from the gyro sensor 54, acceleration sensor 55, geomagnetic sensor 56, barometric altitude sensor 57, and the like. In addition, a camera system 58 mounted on the unmanned aerial vehicle captures an image from the aircraft during flight, and transmits the image to an operator on the ground via the wireless transmitter/receiver 52 . The camera system 58 is provided with a gimbal mechanism driven by a motor, so that the direction of photographing can be changed.

The propellers are driven by motors connected to them, and the motors are driven and controlled via an electronic speed control system ESC (Electric Speed Controller). A drive command from the control computer 51 is given to the ESC and motor units 621, 622, 631, 632, and by controlling the rotational speed of the propeller, translation and rotation can be driven in any three-dimensional direction. I do. Also, the rotational speed of each propeller can be read into the control computer 51 via the ESC and motor units 621, 622, 631, 632 and monitored. Furthermore, by sending a kite wing drive command from the control computer 51 to the wing opening/closing drive system 61, the kite wing 2 can be opened and closed during takeoff and landing. Here, in FIG. 13, the ESC and motor units 621, 622, 631, and 632 are divided into ESC/motor 1 (621), ESC/motor 2 (622), ESC/motor 3 (631), and ESC/motor. 4 (632).

In addition, as described above, it is possible to respond to changes in flight speed by opening and closing the kite wings 2 not only during takeoff and landing, but also during flight. can be performed using the blade opening/closing drive system 61. The opening/closing state of the kite wings 2, that is, the opening/closing angles of the leading edge pipes 23 and 24, can be read into the control computer 51 by the blade opening/closing drive system 61 and confirmed. Further similarly, control of the rudder and elevator can be provided by the rudder drive system 65 and the elevator drive system 66 as required.

Further, in the second embodiment shown in FIGS. 8 to 10, it is necessary to perform a tilting operation to rotate the propellers around the main shafts of the arms 12 and 13. This is transmitted from the control computer 51 to the tilt drive system 64. This can be done by outputting a drive command to the motor. Furthermore, in the second embodiment, it is possible to import the tilt drive state into the control computer 51 and check it.

Incidentally, in the first embodiment shown in FIGS. 1 to 3, etc., the tilt drive system 64 may be omitted. Further, the procedure for flying the unmanned aerial vehicle of the first and second embodiments, ie, the program for executing the control sequence, is stored in the storage unit (not shown) of the control computer 51 . Here, the meaning of the "drive system" in the wing opening/closing drive system 61, the tilt drive system 64, the rudder drive system 65, and the elevator drive system 66 is the configuration for performing each mechanical operation, and the electrical/electronic It is a general term for configurations that perform various controls.

INDUSTRIAL APPLICABILITY As described above, the present invention provides an unmanned aerial vehicle having kite wings, such as that described in Patent Document 1, when the kite wings are opened and closed, the plane formed by the wings and the airframe body thereof The kite wing 2 is provided with a kite wing 2 that can be opened and closed so that the relative relationship with respect to 1 does not change. 2, it is characterized by arranging a plurality of propellers with a substantially vertical rotation axis in a configuration similar to that of a multicopter-type unmanned aerial vehicle.

According to the present invention, in both the first embodiment and the second embodiment, when the kite wings 2 are fully deployed and opened, the position where the kite wings overlap the kite wings 2 when viewed from above, that is, the kite wings Since multiple propellers are arranged on the lower side of 2, the size of the fuselage is the largest when the kite wing 2 is fully opened. It is possible to obtain the effect of being able to plan. On the other hand, when the kite wings 2 are closed, the propeller does not overlap the kite wings 2 when viewed from above, and the airflow generated by the propeller interferes with the kite wings 2 and is affected. It is possible to avoid problems such as

In addition, as one extension (second embodiment) of the present invention, in addition to arranging the kite wings 2 that can be opened and closed and a plurality of propellers, the plurality of propellers are further arranged on the main body 1 of the unmanned aerial vehicle. It is characterized by the provision of a mechanism that enables rotational movement in the direction of the main axis (the direction of the main axis 10 of the fuselage), that is, around a substantially horizontal axis that is perpendicular to the direction of substantially horizontal flight.

Then, according to the second embodiment of the invention, instead of the propulsion propeller used exclusively for horizontal flight, it is possible to operate four propellers 121, 122, 131, 132, and so on. It can be configured so that it does not require the installation of propulsion propellers that are used exclusively for horizontal flight. Alternatively, even if a propeller for propulsion is provided, it is possible to obtain the effect that the propeller for propulsion can have a small output.

Further, in the control method of the present invention, the kite wing 2 is closed and folded during takeoff and landing, and a plurality of The propeller is used to take off and land vertically like a multicopter, and when transitioning from vertical takeoff to horizontal flight, the kite wing 2 is deployed to open the kite wing 2, and from horizontal flight to vertical landing. It is characterized in that the kite wings 2 are folded to a closed state when transitioning.

Further, according to the control method of the present invention, it is possible to realize unmanned flight by effectively utilizing the mechanical configuration for any of the mechanisms of the first embodiment and the second embodiment. Become.

Further, according to the control method according to the second embodiment of the present invention, when the vertical take-off flight transitions to the horizontal flight (Fig. 11), the rotation mechanism (tilt mechanism) is driven following the deployment of the kite wings 2. , the propellers are tilted forward to generate thrust for horizontal flight, while the forward-facing propellers are directed upward prior to the folding of the kite wings 2 when transitioning from horizontal flight to vertical landing flight. , and can be controlled to make a vertical landing with the kite wings 2 closed.

Furthermore, according to the unmanned aerial vehicles of the first and second embodiments of the present invention, the kite wings 2 can be opened and closed not only fully open and fully closed, but also in an intermediate state. The area can be made continuously variable. Then, especially during horizontal flight, it is possible to appropriately control the opening of the kite wings 2 to the intermediate state between the deployment and folding of the kite according to the flight speed. Furthermore, the unmanned aerial vehicle according to the first and second embodiments of the present invention can fly by adaptively selecting the wing configuration according to the purpose of flight, environmental conditions, desired flight speed, etc. It also has the effect of being able to

Further, according to the present invention, the plane formed by the kite wings 2 does not change when the kite wings 2 are opened and closed (the kite wings 2 do not change their angle with respect to the strut 11), and this A kite wing 2 can be provided that can be opened and closed so that the relative relationship of the wing surface of the kite wing 2 to the fuselage body 1 does not change. As a result, regardless of whether the kite wings 2 are open or closed, the center of gravity of the entire fuselage does not change and stays in a fixed position, making it easier to ensure the stability of the fuselage before and after opening and closing the kite wings 2. , can be obtained. In addition, although the lift force received by the wings during flight changes due to the opening and closing of the kite wings 2, the center of lift does not change significantly, so it is relatively easy to ensure flight stability.

In summary, according to the present invention, the advantages of a rotary wing type multicopter, such as vertical take-off and landing and low-speed flight, can be utilized without impairing them, while their disadvantages, such as short cruising time and low transport weight, can be overcome. It can be easily controlled with a small and simple mechanism, and the effective wing area is continuously changed from the fully closed state to the fully opened state. It is possible to carry out flight. And according to the present invention, flight at various flight speeds is possible.

Furthermore, according to the present invention, if necessary, the propeller for vertical take-off and landing can be tilted, as in the second embodiment, so that it can be shared with the propeller for generating thrust for horizontal flight. can be done. Further, according to the unmanned aerial vehicle according to the second embodiment of the present invention, it is possible to provide an unmanned aerial vehicle capable of reducing weight, improving energy efficiency, and extending cruising range.

A plurality of embodiments of the present invention have been described above, but the present invention can be implemented in various other modes. good. And if it is possible to balance the counter torque generated by the rotation of the propeller and secure the degree of freedom related to the operation such as yaw (rudder), pitching (elevator), roll (aileron), and throttle, the number of propellers may be even or odd.

Further, the vertical stabilizer 15 does not necessarily have to have a rudder, and the horizontal stabilizer 16 does not necessarily have to have an elevator. Furthermore, even in the case of the unmanned aerial vehicle of the second embodiment having the tilt mechanism described above, a propeller dedicated to horizontal flight is provided on the upper side of the airframe main body 1 or the like, with a rotating shaft parallel to or parallel to the airframe main axis 10. You can

In carrying out the present invention, methods for flying an unmanned aerial vehicle include a method of controlling from the ground, a method of autonomous flight along a pre-planned flight route, and sensors mounted on the aircraft during flight. Various methods are conceivable, such as a method based on intelligent control that recognizes the environment situation using , and realizes flight by recognizing its own position while creating a map of the surroundings. can also apply the control sequence of the present invention.

The unmanned aerial vehicle according to the present invention has the features described above, and is suitable for rapid and stable delivery in logistics applications such as flying with cargo on board and delivering it to a remote location. In applications such as realization, inspection of structures, and disaster relief, it is possible to flexibly realize flight according to each application, such as selecting the flight speed according to the need for each inspection or confirmation point. is.

1 Aircraft body
2 kite wings
10 machine spindle
11 Posts
12, 13 arms
15 Vertical Stabilizer
16 horizontal stabilizer
19 legs
21 Central spindle pipe (central spindle)
22 hinge plate
23, 24 Front edge pipe (opening/closing frame member)
25, 26 wing middle rib
27 Leading Edge Pipe Drive Assembly
28 Slide drive mechanism (modification of first embodiment)
50 control unit
51 Control computer
52 Radio Transceiver
53 GPS receiver
54 Gyro sensor
55 Accelerometer
56 Geomagnetic sensor
54 barometric altitude sensor
58 camera system
621, 622, 631, 632 ESC/motor
61 Wing open/close drive system
64 tilt drive system
65 Rudder drive system
66 Elevator drive system
121, 122, 131, 132, 170 Propeller
230, 240 gear
231, 232, 241, 242 Leading Edge Pipe Drive Link
233, 243 Leading Edge Pipe Drive Link (Another Method (Modified Example of First Embodiment))

Claims (6)

In an unmanned aerial vehicle having a kite wing attached at a predetermined angle to the airframe body,
an opening/closing frame member arranged symmetrically with respect to the central main axis of the kite wing and rotatable around a front portion;
at least three propellers provided on the fuselage body,
The kite wings are flexible and supported by the opening/closing frame member, and are opened and closed by rotation of the opening/closing frame member,
at least one propeller is arranged to be positioned inside the kite wing when the kite wing is in a fully open state and viewed from above;
An unmanned aerial vehicle characterized by The at least three propellers are tiltable between an orientation in which the airframe body is oriented in the vertical direction and an orientation in which the airframe body is oriented in the longitudinal direction;
3. The unmanned aerial vehicle of claim 1, wherein: In a control method for an unmanned aerial vehicle having kite wings attached at a predetermined angle to the airframe body,
The unmanned aerial vehicle is
an opening/closing frame member arranged symmetrically with respect to the central main axis of the kite wing and rotatable around a front portion;
at least three propellers provided on the fuselage body,
The kite wings are flexible and supported by the opening/closing frame member, and are opened and closed by rotation of the opening/closing frame member,
at least one of the propellers is arranged to be positioned inside the kite wing when the kite wing is in a fully open state and viewed from above;
capable of control in at least a climb mode, a level flight mode, and a descent mode;
in the climb mode, retracting the kite wings and generating thrust for ascent by the at least three propellers;
in the horizontal flight mode, deploying the kite wings;
generating thrust for descent by the at least three propellers in the descent mode;
A control method for an unmanned aerial vehicle, characterized by: wherein the at least three propellers are tiltable between an orientation in which the airframe body is oriented in the vertical direction and an orientation in which the airframe body is oriented in the longitudinal direction;
Control is possible in the first transition mode and the second transition mode,
In the first transition mode,
changing the attitude of the at least three propellers from facing the vertical direction of the airframe body to facing the longitudinal direction of the airframe body;
deploying the kite wings;
In the second transition mode,
shrinking the kite wings,
changing the attitude of the at least three propellers from facing the longitudinal direction of the airframe body to facing the vertical direction of the airframe body;
The method for controlling an unmanned aerial vehicle according to claim 3, characterized by: changing the opening degree of the kite wings according to the flight speed in the horizontal flight mode;
The method for controlling an unmanned aerial vehicle according to claim 1 or 2, characterized by: tilting only some propellers of the propellers capable of tilting;
The method for controlling an unmanned aerial vehicle according to claim 1 or 2, characterized by:

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