JP2008081094A - Ornithopter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent ornithopter having an excellent power transmission efficiency and capable of performing an alert and highly maneuvarable flight by performing a flapping motion with a high flapping frequency since a large output can be provided by rotatingly driving a rotary motor at high speeds without requiring a complicated and heavy drive control circuit device and the large output from the rotary motor is converted into a flapping motion without a large mechanical loss. <P>SOLUTION: In this resonance ornithopter, a flapping blade forms a blade vibration system performing a compound resonance in two degree-of-freedom; flapping vibration and feathering vibration. A vibrating motor generating an inertia force in the circumferential direction by the flapping blade pivotally supported on a flapping vibration pivot shaft is supportedly installed. A flapping vibration torque and a feathering vibration torque can be provided by the inertia force generated by the vibrating motor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a flapping airplane, and more particularly to a resonant flapping airplane. The present invention is suitable for a micro flying vehicle that flies by flapping flight.

  In recent years, along with the miniaturization and miniaturization of industrial products and the progress of manufacturing technology thereof, practical development of small flying vehicles (MicroAerialVehicle) has been rapidly advanced. A small flying vehicle (MicroAerialVehicle) refers to a small and unmanned aircraft that is capable of autonomous flight, and is able to perform meaningful observation activities by taking advantage of its mobility and autonomy. .

  In particular, the development of an insect-type small flying vehicle (MicroAerialVehicle) that flies by flapping flight realizes high mobility such as hovering, sudden start, sudden stop, and sudden turn that enables autonomous observation activities in a closed small space. If it is expected to be able to do so, for example, the purpose is to quickly grasp the situation in a fire scene that is dangerous to human observation activities, a hazardous substance leak site, or a building that may collapse It is expected to be active in unmanned observation activities and others.

  Insect-type small flying object (MicroAerialVehicle) flying by flapping flight will utilize the flapping motion of insects with excellent flight characteristics to achieve amazing high maneuverability flight that greatly surpasses the flight performance of conventional aircraft However, the excellent flight characteristics of these insects can be attributed to the fact that a large aerodynamic force can be generated instantaneously by their high flapping frequency. Recent research in the field of unsteady aerodynamics has shown that the aerodynamic force generated by the flapping motion is proportional to the square of the flapping frequency, but more generally, for example, high above 100 Hz. Insects such as bees flying at a flapping frequency can fly relatively agile, but insects such as butterflies whose flapping frequency stays at about 10 Hz cannot fly such agile. Can do.

  Many inventions have been made on flapping mechanisms of flapping airplanes, but most of them are forced vibration type flapping mechanisms using various cams, link mechanisms and the like. The forced vibration type flapping mechanism generally obtains flapping motion by forcibly driving a blade axis provided on a rigid body with a constant amplitude by an actuator to obtain a flapping motion. For example, a rotational output of a DC electromagnetic motor or an ultrasonic motor is appropriately geared. -Down and transmitted to the scotch-yoke mechanism, and the scotch-yoke mechanism flutters the rigid body provided with the reciprocating linear output by converting the input rotational output into a reciprocating linear output. A flapping mechanism that obtains flapping motion by forcibly oscillating the blade axis of the blade with a constant amplitude can be given. (At this time, by using a so-called membrane method in combination, an inertial force and aerodynamic force generated by the flapping motion can be applied to the flapping wing, whereby a feathering motion can be generated in the flapping wing. )

  However, such a forced-vibration type flapping mechanism mechanically generates the entire process of the flapping motion by forced driving, and thus, for example, sliding by sliding friction resistance around the flapping rotation support shaft of the flapping wing is performed. In addition to dynamic friction loss, the mechanical work loss due to the drive mechanism such as the scotch / yoke mechanism and the gear down mechanism of the rotary motor is a heavy burden, and the limited rotation supplied by the DC electromagnetic motor or ultrasonic motor Depending on the output, it has been difficult to make the forced-vibration type flapping airplane flutter at a high flapping frequency of 20 Hz or higher. For this reason, in such a forced vibration type flapping airplane, it was impossible to realize the agile and high maneuvering flight required for the above-described insect type ultra-small flapping airplane.

  On the other hand, the flapping wing shaft is configured to be elastically supported by an elastic body such as a leaf spring, and the flapping wing flapping vibration is obtained by causing the flapping wing to resonate at the natural frequency of the blade vibration system. Because a large flapping vibration amplitude can be obtained by exciting vibration with a large amplitude, there is no need to drive the forcing mechanism against the friction force and other forces, unlike the forced vibration type flapping mechanism. Since the mechanical work loss including the sliding friction loss, which was a problem in the flapping mechanism of the mold, can be kept relatively small, the mechanism for the output even when the same DC electromagnetic motor or ultrasonic motor is used as the output source. Excellent in flapping motion at a higher flapping frequency compared to the forced vibration type flapping mechanism. It can be said to be Bataki mechanism.

An invention relating to a resonance type flapping mechanism capable of realizing flapping motion at a high flapping frequency that cannot be realized by a forced vibration type flapping mechanism is disclosed in Patent Document 1 (see Patent Document 1). In Patent Document 1, an electromagnetic motor or an ultrasonic motor is used as a blade driving motor, and a drive output rod serving as a blade axis of the flapping blade is vibrated by rotating the rotation output shaft of the blade driving motor forward and backward. Thus, by causing the drive rod elastically supported by the elastic member to resonate at the natural frequency of the configured vibration system, flapping vibration of the flapping wing can be obtained, and a resonance type flapping mechanism can be obtained. Such an invention is disclosed. (In Patent Document 1, it is disclosed that the invention can passively obtain a feathering motion by applying air resistance to a flapping wing, that is, a membrane method.)
JP 2006-088769 A

  However, when the flapping vibration is obtained by driving the blade axis of the flapping wing at a high frequency by driving the electromagnetic motor or the ultrasonic motor forward / reversely, the rotation of the rotating motor and the flapping wing Vibration control of the excitation vibration that can be realized by this method, because switching control between forward and reverse rotation of the rotary motor that is driven by repeatedly reversing the rotation direction of the rotary motor against inertia is performed each time. It can be said that the number is limited in time by the influence of the control response delay.

  Further, in the case of the method in which the rotary motor is driven forward / reversely at a high frequency repeatedly, the rotational speed (rotational speed) of the rotary motor is not sufficiently accelerated to reach high speed rotation. Therefore, the power (output) that can be output by the rotary motor is limited, so that the purpose of the original output device of the rotary motor to output and supply the power necessary for flapping flight cannot be sufficiently achieved. It becomes. In other words, in the case of the method using the rotary motor driven forward / reversely, it is difficult to desire high-speed rotation drive with a large output of the rotary motor sufficient to output and provide the necessary power necessary for flapping flight. It can be said that.

  Furthermore, mounting a complicated drive control circuit device for forward / reverse driving of the rotary motor on the flapping airplane is accompanied by a considerable increase in weight, and can be said to be a heavy burden on the flight of the flapping airplane. . The problem of an increase in the weight of the drive control circuit device can be more noticeable in the vibration vibration device of a resonance type flapping airplane using a piezo vibration element or an artificial muscle. For example, in order to drive a 4.8 g piezoelectric vibration element in vibration, it is necessary to use a DC-DC converter that boosts a 7.4 V DC power supply to 2000 V as a drive control circuit device. Since the weight of the circuit) is approximately 126 g, a setting example is known in which the weight of the drive control circuit device occupies about 26 times the weight of the vibration vibration output element itself.

  The present invention has been made in view of these circumstances. A rotary motor is driven at high speed to obtain a large output without requiring a complicated and heavy drive control circuit device, and a large output output from the rotary motor is obtained. Providing an excellent flapping airplane that excels in power transmission efficiency by converting to flapping motion without significant mechanical loss, and in addition, fluttering motion at high flapping frequency enables agile high maneuver flight For the purpose.

  The present invention has the following configuration in order to solve the above problems. That is, the flapping airplane according to the present invention is a resonance type flapping airplane, in which the flapping wings constitute a wing vibration system in which coupled flapping vibrations are performed in two degrees of freedom of flapping vibration and feathering vibration. A vibration motor that generates an inertial force in the circumferential direction is supported by the flapping wings provided, and a flapping vibration torque and a feathering vibration torque are obtained by the inertial force generated by the vibration motor.

  Further, the present invention is characterized in that a joint joint for engaging the flapping wings pivotally supported by the flapping vibration support shaft as a pair of left and right is further provided, and the vibration motor is fixed to the joint joint.

  The joint joint is made of an elastic body.

  According to the present invention, in a resonating type flapping airplane, a flapping wing is configured such that a flapping wing vibrates in two degrees of freedom of flapping vibration and feathering vibration, and the flapping is pivotally supported by a flapping vibration support shaft. A complicated and heavy drive control circuit device is provided by supporting a vibration motor that generates an inertial force in the circumferential direction by a blade, and obtaining a flapping vibration torque and a feathering vibration torque by the inertial force generated by the vibration motor. By driving the vibration motor at a high speed in a certain direction without the need for rotation, the inertial force generated by the vibration motor in the circumferential direction can be used to generate high-power, high-frequency flapping vibration torque and feathering vibration torque. Obtainable.

  Further, according to the present invention, the flapping vibration torque and the feathering vibration torque, which are the outputs of the vibration motor, are maximized by the resonance vibration at the natural frequency of the flapping blade vibration system without a large mechanical loss such as a friction loss. Since it can be transmitted to the flapping wing vibration system with power transmission efficiency, flapping motion with large amplitude efficiently in the flapping wing vibration system configured as a two-degree-of-freedom coupled resonance vibration system of flapping vibration and feathering vibration Can be realized.

  According to the present invention, there is further provided a joint joint that engages the flapping wings pivotally supported by the flapping vibration support shaft as a pair of left and right, and is configured to include the vibration motor fixed to the joint joint. The pair of left and right flapping wings can be vibrated simultaneously by one vibration motor.

  According to the present invention, the joint joint is made of an elastic body, so that the vibration motor is elastically supported by the elastic body without providing a complicated joint mechanism, and the pair of left and right flapping wings are elastically joined. Therefore, the rotational displacement of the vibration motor and the flapping motion of the flapping wing with the flapping vibration support shaft as the rotation axis are allowed to be allowed by the elastic deformation of the elastic body. Can be suitably obtained.

  Hereinafter, embodiments of the flapping airplane according to the present invention will be described in detail. FIG. 1 is an explanatory view of a full view of a flapping wing drive unit in a flapping airplane according to the present embodiment as viewed from the front upper wing end side of the left wing. The flapping airplane of the present embodiment is a dragonfly type MAV (MicroAerial Vehicle) having 2 to 4 flapping wings, and is twice as large as an actual dragonfly (Anax-Parthenope-julius) and designed to have a weight of 20 g. Yes. Its total length is 250 mm and the span length is 200 mm.

Four flapping wings 1 made of low-foamed styrene resin (density 40 kg / m ³ ) are provided in a rectangular shape, the cord length is 20 mm, the plate thickness is 3 mm, and the flapping wing 1 The weight of the sheet is designed to be 1.43 g including the weight of the internal structure. These four flapping wings are divided into two pairs of front wings and two pairs of rear wings, and are each mounted and supported on a mounting block 2 made of duralumin. In this embodiment, the design is made with a flapping wing made of a rectangular flat plate that is easy to manufacture and relatively strong, but the flapping wing can of course have any plane shape and airfoil shape. In addition, in FIG. 1 to FIG. 5, which is an explanatory diagram of this embodiment, and in FIG. 8 showing another embodiment, the flapping wings in the drawings are drawn with a wing shape in order to help the visual understanding thereof. Shall.

  FIG. 2 and FIG. 3 are explanatory views in which the attachment support portion of the front wing of the flapping airplane in this embodiment is enlarged. The flapping wing 1 is cantilevered by an aluminum flapping vibration spring 11 having a length of 10 mm, a width of 5 mm, and a plate thickness of 0.37 mm at the exposed portion, and one end of the flapping vibration spring 11 is made of duralumin. The fulcrum block 10 and the opposite end are fixedly buried in the flapping wing 1.

  FIG. 4 and FIG. 5 are explanatory views in which the attachment support portion of the front wing of the flapping airplane in this embodiment is further enlarged. The fulcrum block 10 which is the mounting base of the front wing is supported by a flapping vibration support shaft 21 having a cylindrical shaft shape supported by a pair of flanges provided on the mount block 2, and the flapping vibration support shaft. 21 is provided so as to be rotatable around 21. Further, the pair of left and right fulcrum blocks 10 are engaged by the joint joint 3, and the vibration motor 4 is fixedly held by press fitting into the joint joint 3 as shown in the figure. The joint joint 3 is an elastic body made of silicone rubber, and is provided so that it can be elastically deformed moderately. Therefore, the fulcrum block 10 rotates around the flapping vibration support shaft 21 with a small amplitude. When vibrating, the rotational vibration operation is not greatly hindered. Of course, by providing an appropriate heat dissipation hole in the joint joint 3 shown in the figure, the vibration motor 4 that generates heat by rotational drive can also be provided so that heat can be efficiently dissipated.

  The vibration motor 4 has an eccentric weight 42 made of a sintered tungsten alloy attached to the output shaft of a DC electromagnetic motor 41 having a diameter of 4 mm. The electrode 43 of the DC electromagnetic motor 41 is connected to a small lithium polymer battery. Yes. The balance between the weight distribution of the eccentric weight 42 and the rotational moment of inertia, as well as the current and voltage values supplied to the DC electromagnetic motor 41, are adjusted in advance, and the vibration motor 4 is constant at a constant speed at 2040 rpm. It is provided to rotate. At this time, since the vibration motor 4 can output a large inertia force (centrifugal force) equally in the circumferential direction of the rotation surface of the eccentric weight 42, specifically on the output vector line of the inertia force. Since the flapping vibration support shaft 21 of the flapping wing is located, the moment arm is temporarily lost, and the rotational torque cannot be applied around the flapping vibration support shaft 21. Except for a part of the inertia force, the output by the inertia force generated evenly in the circumferential direction of the rotation surface of almost all the eccentric weights 42 is converted into the flapping vibration torque around the flapping vibration support shaft 21. Can be converted and output.

In the mechanism described above, as described above, the vibration motor 4 is driven at a constant rotation at 2040 rpm in a fixed direction, so that the flapping vibration shaft 21 is rotated around the flapping vibration support shaft 21 at a flapping frequency of 34 Hz which is the design flapping frequency of the flapping airplane of this embodiment. Since the wrapping vibration torque is generated, the fulcrum block 10 is rotationally vibrated with a small amplitude around the flapping vibration support shaft 21 by the flapping vibration torque. Therefore, the natural frequency ω of the flapping vibration shown in the present embodiment. _The flapping wing vibration system comprising the flapping wing 1 and the flapping vibration spring 11 with _φ designed to be 32.7 Hz resonates in the flapping vibration, so that a flapping vibration amplitude of 40 ° can be obtained immediately. .

  Further, the flapping airplane shown in the present embodiment is provided so that the feathering vibration (movement) is naturally coupled to the flapping vibration (movement) of the flapping wing described above. FIG. 6 is an explanatory diagram showing the internal structure of the flapping wing of the flapping airplane in this embodiment. On the feathering shaft 5 mm from the front edge of the flapping wing, an inner girder 12 made of duralumin having a diameter of 0.5 mm, which is the main girder of the flapping airplane, is fixed to the spring 11 for flapping vibration.

  On the outer periphery of the inner girder 12, an outer girder 13 having an outer shape of 0.51 mm, which is a thin collar made of resin, is assembled without being fixed. Therefore, the outer girder 13 slides on the outer peripheral surface of the inner girder 12 and is provided so as to be freely rotatable while maintaining the same axis as the inner girder 12. Here, the flapping wing 1 made of low-expansion styrene resin is provided without being fixed to the inner girder 12 like the outer girder 13, and is adhered and fixed on the outer peripheral surface of the outer girder 13. Therefore, the outer girder 13 is integrated with the outer girder 12 so that it slides on the outer circumferential surface of the inner girder 12 and can freely rotate around the inner girder 12.

  In addition, on the chord line of the flapping wing perpendicular to the inner girder 12, two aluminum feathering vibration springs 14 having a length of 12 mm, a width of 2.5 mm, and a plate thickness of 0.1 mm as shown in the figure. It is buried and fixed in the girder 12. Here, the flapping wing 1 made of low-foamed styrene resin is fixed only to the tip of the feathering vibration spring 14, and the flapping wing 1 and the feathering vibration spring 14, except for the fixed portion, Are provided so as not to contact each other.

  This is to allow free deformation due to the vibration of the feathering vibration spring 14. In consideration of the vibration mode of the feathering vibration spring 14, the feathering vibration spring 14 is placed inside the flapping wing 1. An internal space is provided around. Of course, if necessary, the blade surface of the flapping wing 1 may be cut open to provide a space for the feathering vibration spring 14 to vibrate, or the feathering vibration spring 14 may be provided as the blade root of the flapping wing 1. Further, it may be provided at the wing tip, and the whole of the wing tip may be exposed except for the connecting and fixing portion with the flapping wing 1.

  In addition to the above, from the end face of the fulcrum block 10 which is the fixed surface of the flapping vibration spring 11 to the fulcrum block 10, the outer side in the 50.6 mm span direction and the position of the trailing edge of the flapping wing Is provided with a steel concentrated load weight 15 having a weight of 1.22 g. The concentrated load weight 15 causes the flapping motion of the flapping wing to generate a feathering motion in which the inertial force acting on the concentrated load weight 15 naturally couples to the flapping motion of the flapping wing. So that the phase advance angle of the feathering motion with respect to the flapping motion is a phase difference of 90 °, which is considered to be the most efficient from the viewpoint of the propulsion efficiency of the flapping motion. The weight and arrangement position of the concentrated load weight 15 are taken into consideration.

  Specifically, the shape, material, weight and weight distribution of the flapping wing of the flapping airplane shown in the present embodiment, and the flapping motion are such that a sufficiently large vibration amplitude of the wing vibration system can be obtained by a simple and lightweight structure. Although it was determined by the optimal structure design based on the numerical analysis using the computer by the inventor of the present invention, detailed description of the process is omitted here. Of course, the present invention can be applied to any resonance type flapping airplane based on a free structural design.

Since the natural frequency ω _θ of the feathering vibration of the flapping wing in the mechanism described above is designed to be 34 Hz, which is the same value as the vibration frequency of the vibration vibration by the vibration motor 4, the vibration to the feathering vibration is excited. As a result of efficient energy injection, a 30 ° feathering oscillation amplitude can be obtained immediately. Needless to say, the feathering vibration that is generated here in combination with the flapping vibration of the flapping wing is the two-degree-of-freedom coupled resonance vibration system of the flapping vibration and the feathering vibration shown in this embodiment. A feathering vibration by a resonance vibration that resonates and couples with the flapping vibration in a flapping wing, and the feathering vibration from the excitation vibration output in the two-degree-of-freedom coupled resonance type flapping airplane shown in this embodiment. It can be said that the power transmission efficiency is significantly improved compared to the power transmission efficiency of the feathering motion by the membrane method which is a simple forced vibration type drive mechanism.

  FIG. 7 is an explanatory diagram showing the entirety of a registration mark type MAV (MicroAerial Vehicle) shown in this embodiment. FIG. 7 is a layout view illustrating the flapping airplane of this embodiment as seen from the port side. In the dragonfly type MAV (MicroAerial Vehicle) of the present embodiment, the stroke surface inclination angle (referred to as the inclination angle of the flapping stroke surface with respect to the horizontal plane) suitable for hovering flight is already set as the attachment angle. The flapping wing drive unit having the mount block 2 and the flapping wing 1 which are detailed as to the mechanism as main components is obliquely attached to the fuselage, and the flapping wing 1 is provided in a direction perpendicular to the paper surface. .

  In FIG. 7, 61 is a super wide-angle CCD camera for observation which is the only pay load in the flapping airplane, 62 is a vibration gyro for inertial navigation (weight 0.5 g), and 63 is for flight control and wireless communication. This is a control unit with an IC package. The dragonfly type MAV (MicroAerial Vehicle) of this embodiment is used for a remote observation mission, and the observer observes the image of the ultra-wide-angle CCD camera 61 transmitted by wireless communication through the control unit 63 at a remote place. On the other hand, the control unit 63 and the vibrating gyroscope 62 automatically fly a dragonfly-type MAV (MicroAerialVehicle) that autonomously flies by inertial navigation by instructing the direction necessary for observation newly by the same wireless communication. Obtain observational images.

  64 is a battery (weight 3.7 g) provided at the center of gravity of the flapping airplane, and 65 is a movable horizontal tail (flying) for changing the tilt angle of the stroke plane driven by a linear motor using a piezoelectric vibration element.・ Tail). When the flapping airplane makes a forward flight, the thrust necessary to surpass the drag that increases in proportion to the square of the forward speed must be obtained by greatly inclining the stroke surface inclination angle. The movable horizontal tail 65 is provided for this purpose, and in accordance with the flight control instruction of the flapping airplane, a necessary pitching moment is applied around the center of gravity of the aircraft using aerodynamic force, and a desired stroke plane inclination angle is provided. It has the effect of obtaining.

  Note that the dragonfly type MAV (MicroAerial Vehicle) shown in the present embodiment realizes flapping motion at a flapping frequency that is approximately the same value as the flapping frequency of an actual dragonfly (Anax-Parthenope-julius). It is possible to fly with high agility that greatly surpasses the flight performance. In addition, since a vibration motor that is driven to rotate at a high speed in a certain direction is used as an output source, a high output can be obtained and a flapping flight can be achieved without requiring a complicated and heavy drive control circuit device. Further, since the pair of left and right flapping wings are engaged by a joint joint made of an elastic body that fixes and holds the vibration motor, the pair of left and right flapping wings can be simultaneously vibrated by one vibration motor. In addition, since the flapping wing is provided with a blade vibration system so that the flapping vibration and the feathering vibration are coupled in two degrees of freedom, the flapping vibration efficiently and with a large amplitude flapping motion is achieved with maximum power transmission efficiency. Can be realized.

  As mentioned above, although the individual specific form was shown and explained in detail about embodiment of the flapping airplane concerning the present invention, exemplary embodiment presented here is indicated in order to guide suitable practice about the present invention. However, the technical scope of the embodiments of the present invention is not defined, and the embodiments according to the present invention cover all the embodiments based on the present invention. For example, as shown in FIG. 8, it is assumed that two vibration motors are arranged in parallel in the left and right directions, and the vertical force of inertia force generated by the two vibration motors by rotating the two vibration motors in opposite directions. A configuration in which an output component other than a direction component is canceled (offset) to obtain a flapping vibration torque and a feathering vibration torque, or a plurality of flapping wings 1 are provided in one fulcrum block 10, Of course, the configuration in which the flapping wing 1 is vibrated simultaneously by the one fulcrum block 10 is also an embodiment according to the present invention.

  It is explanatory drawing which shows the flapping wing drive part of the resonance type flapping airplane by this invention seeing from the left wing front upper wing end side.   It is explanatory drawing which shows the flapping wing drive part of the front wing of the resonance type flapping airplane by this invention seen from the left wing front upper wing end side.   It is explanatory drawing which shows the flapping wing drive part of the front wing of the resonance type flapping airplane by this invention seen from the right wing rear upper wing end side.   FIG. 4 is an enlarged explanatory view showing a flapping wing driving unit of a front wing of a resonance type flapping airplane according to the present invention as seen from the front.   It is an expansion explanatory view which shows the flapping wing drive part of the front wing of the resonance type flapping airplane by this invention seeing from back.   It is explanatory drawing which sees the internal structure of the flapping wing of the front wing of the resonance type flapping airplane by this invention from the left wing front upper wing end side.   It is arrangement | positioning explanatory drawing which shows the resonance type flapping airplane by this invention seeing from the port side.   It is explanatory drawing which shows the other Example of the resonance type flapping airplane by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flapping wing 2 Mount block 3 Joint joint 4 Vibration motor 10 Support block 11 Flapping vibration spring 12 Inner girder 13 Outer girder (thin color)
14 Feathering vibration spring 15 Concentrated load weight 21 Flapping vibration support shaft 41 DC electromagnetic motor 42 Eccentric weight 43 Electrode 61 Super wide angle CCD camera 62 Gyro sensor 63 Control unit 64 Battery 65 Movable horizontal tail

Claims (3)

  In a resonating type flapping airplane, the flapping wings form a wing vibration system in which the flapping wings vibrate in two degrees of freedom of flapping vibration and feathering vibration. A flapping airplane characterized by supporting a vibration motor that generates inertial force, and obtaining flapping vibration torque and feathering vibration torque by the inertial force generated by the vibration motor.   The vibration motor is provided according to claim 1, further comprising a joint joint that engages the flapping blades pivotally supported by the flapping vibration support shaft as a pair of left and right sides, and is fixed to the joint joint. Flapping airplane.   The flapping airplane according to claim 2, wherein the joint joint is made of an elastic body.

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