Flapping device

Abstract

[Problem] To provide a flapping device in which various adjustments can be easily made. [Solution] A flapping device 1 comprises blades 2, 2, and drive units 3 provided corresponding to the blades 2, 2. The drive units 3 each comprise a drive source 30, a driven portion 10 that rotates about a first axis, a first biasing member 40 that applies a biasing force to the driven portion 10 in a direction opposite to the rotation of the driven portion 10, a second biasing member 41 that applies a biasing force to the driven portion 10 in a direction opposite to the biasing force of the first biasing member 40, and a control unit 60. The blade 2 comprises: a blade shaft 20 that extends in a second axis direction intersecting with the first axis, has one end side connected to the driven portion 10, and is rotatable around the second axis; a blade support member 21 that extends in a direction intersecting with the blade shaft 20 on a base end side of the blade shaft 20 and is rotatable integrally with the blade shaft 20; and a blade body 22 that rotates integrally with the blade shaft 20. The flapping device 1 comprises: a body frame 7 that rotatably supports the driven portion 10; a suspending portion 72; and a spherical shell-shaped leg portion 75.

Description

Flapping apparatus

[0001] The present invention relates to a flapping apparatus that obtains lift by swinging blades.

[0002] Conventionally, flapping apparatuses have been used for surveillance, photography, various inspections and the like from the air. As the aforementioned flapping apparatus, an ultra-micro flapping wing airplane system (hereinafter simply referred to as a flapping apparatus) that directly drives flapping wings (corresponding to blades) by a DC motor is known (e.g., Patent Document 1).

[0003] Meanwhile, in recent years, flapping apparatuses have also been used in toys and the like along with the diversification of applications. Further, for surveys, repairs, photography and the like in narrow spaces, there is a demand for flapping apparatuses that are compact and capable of flying in various flight modes. In such a flapping apparatus, the weight balance of a pair of left and right blades and the balance of lift generated by flapping occupy an important position for maintaining levitation stability. Further, in order to maintain the balance of lift in the flapping apparatus, it is necessary to adjust the balance of biasing means such as torsion springs that generate the lift of the blades, and rigidity for receiving the biasing force from the biasing means is also required.

[0004] US Patent Application Publication No. 2016 / 0159477

[0005] However, the flapping apparatus described in Patent Document 1 has a wide bottom surface, and it is difficult to grasp the left-right weight balance when the apparatus is placed on the ground or the like. Therefore, in the flapping apparatus described in Patent Document 1, adjusting the weight balance and the balance of lift generated by flapping must be performed while the flapping apparatus is flying, and the flapping apparatus needs to be flown for each adjustment, which causes a problem that the adjustment takes time.

[0006] Accordingly, an object of the present invention is to provide a flapping apparatus that can increase the power-to-weight ratio at low cost and can be configured to be compact. Further, an object of the present invention is to provide a flapping apparatus that allows various adjustments to be easily performed.

[0007] (1) The flapping device of the present invention, provided to solve the above-mentioned problems, comprises a pair of blades and a drive unit provided corresponding to each of the pair of blades, wherein the drive unit comprises a drive source, a driven part that rotates around a first axis upon receiving power output from the drive source, a first biasing member that applies a biasing force to the driven part in the opposite direction to the rotation direction of the driven part in conjunction with the rotation of the driven part, a second biasing member that applies a biasing force to the driven part in the opposite direction to the biasing direction of the first biasing member, and a control unit that controls the output of the driving force from the drive source, wherein the blades are positioned in the direction of a second axis intersecting the first axis The invention is characterized by comprising: a blade shaft that extends in a direction and is connected to the driven part at one end and is rotatably connected around the second axis; a blade support member that extends in a direction intersecting the blade shaft at the base end of the blade shaft and is rotatably connected integrally with the blade shaft; a blade body that is supported by the blade shaft and the blade support member and rotates integrally with the blade shaft; a main body frame that rotatably supports at least the driven part and supports the drive source; a suspension part suspended below the main body frame; and a spherical shell-shaped leg part that is provided at the lower end of the suspension part and forms part of a sphere.

[0008] In the flapping device of the present invention described above, the first biasing member and the second biasing member can apply biasing forces in opposite directions to the driven part, so the restoring forces of the first biasing member and the second biasing member can be linearized. Therefore, the flapping device of the present invention can distribute the stroke related to the flapping of the blades in a well-balanced and symmetrical manner. As a result, the flapping device of the present invention can stabilize the lift and flight, and thus improve flight accuracy. Furthermore, the flapping device of the present invention can excite the blade shaft in the direction around the first axis by the biasing of the first biasing member and the second biasing member. Therefore, the flapping device of the present invention can amplify the flapping frequency of the pair of blades by excitation, so the pair of blades can be driven at high speed. As a result, a strong lift force can be obtained. Here, for the first biasing member and the second biasing member, it is preferable to use materials that can bias in the torsional direction, such as torsion springs. Also, the main frame is preferably constructed from a material such as aluminum. This ensures sufficient rigidity to withstand the biasing force from the first and second biasing members and the load from the flapping of the blades, while also suppressing an increase in the weight of the device itself.

[0009] Furthermore, since the flapping wing device of the present invention allows for independent drive control of each of the two drive sources, it enables flight in various directions. Here, various types of motors can be used as drive sources, but brushless DC motors, which allow for easy forward and reverse rotation and have a high power-to-weight ratio, are preferably used. This makes battery operation easy and control can be easily performed.

[0010] Furthermore, the flapping device of the present invention is equipped with a spherical shell-shaped leg portion that forms part of a sphere at the lower end of the suspension portion on the lower side of the main frame. Therefore, when the flapping device of the present invention is placed on the ground or a table, the leg portion can prevent it from tipping over. In addition, since the main body of the flapping device of the present invention can be supported by the leg portion, it is possible to adjust the lift force (such as adjusting the flapping stroke) and the weight balance while applying lift force near the boundary of whether or not it is lifted. Therefore, the flapping device of the present invention can be adjusted quickly without having to fly it each time an adjustment is made.

[0011] Here, adjustments can be made using various sensors provided by the flapping device. For example, it is desirable to measure the left and right drive voltage balance (corresponding to roll), the drive voltage offset of both blades (corresponding to pitch), the Split Cycle Factor (corresponding to yaw), etc., and adjust them so that each reaches a neutral point. Here, the Split Cycle Factor represents the difference in front and rear flapping strokes when a difference is created in the periods of the front and rear flapping strokes, while keeping the period of one flapping cycle (front and rear strokes) constant. Furthermore, since the above adjustments change with the driving force, it is desirable to measure with multiple driving forces and supplement the adjustment amount by prediction. Here, it is desirable that the spheres forming part of the legs be spheres with a diameter at least that passes through the lowest point of the blade when the flapping device is viewed from the front. Furthermore, it is desirable that the legs have a diameter between the base ends of each of the pair of blade axes when viewed from below. As a result, the flapping device of the present invention can prevent the device from tipping over without unnecessarily increasing the size of its legs. In other words, by utilizing the spherical surface of the legs, the flapping device of the present invention can effectively prevent tipping over when placed on the ground or the like, as the device body oscillates.

[0012] (2) The flapping device of the present invention described above is preferably characterized by having a stopper that limits the rotation of the blade shaft to a predetermined rotation angle, and a limiter that is provided so as to be rotatable integrally with the blade support member and limits the rotation of the blade shaft by contacting the stopper.

[0013] The flapping device of the present invention described above, when configured as in (2) above, can suppress the rotation of the blade shaft beyond a predetermined range. That is, since the blade shaft of the flapping device of the present invention rotates within a predetermined range, the angle of attack of the blades can be maintained within an appropriate range. Therefore, the flapping device of the present invention can stably generate lift force from the blades. Here, the rotation angle by the stopper can be set according to the twist angle of the blades, for example, it is good to set the rotation angle to +45 degrees to -45 degrees. Also, since the tip side (outside) of the blade is prone to twist deformation, it is good to set the rotation angle by the stopper to be in the range of +37 degrees to -37 degrees, taking this into consideration.

[0014] (3) The flapping device of the present invention, provided to solve the above-mentioned problems, comprises a pair of blades and a drive unit provided corresponding to each of the pair of blades, wherein the drive unit comprises a drive source, a driven part that rotates around a first axis upon receiving power output from the drive source, a first biasing member that applies a biasing force to the driven part in the opposite direction to the rotation direction of the driven part in conjunction with the rotation of the driven part, a second biasing member that applies a biasing force to the driven part in the opposite direction to the biasing direction of the first biasing member, and a control unit that controls the output of the driving force from the drive source, wherein the blades are positioned along a second axis that intersects the first axis The invention comprises a blade shaft extending in the direction and connected to the driven part at one end and rotatably connected around the second axis; a blade support member extending in a direction intersecting the blade shaft at the base end of the blade shaft and rotatably connected integrally with the blade shaft; and a blade body supported by the blade shaft and the blade support member and rotatably connected integrally with the blade shaft, wherein the invention is characterized by comprising a stopper that limits the rotation of the blade shaft to a predetermined rotation angle, and a limiter that is rotatably provided integrally with the blade support member and limits the rotation of the blade shaft by contacting the stopper.

[0015] In the flapping device of the present invention described above, the wing support member provided on the base end side of the wing shaft rotates together with the wing shaft, so that the wing can be rotated while supporting the inner end of the wing root. Therefore, in the flapping device of the present invention, the wing can be rotated around the wing shaft while the longitudinal direction of the wing root is supported by the wing shaft and the short direction of the wing root is supported by the wing support member. As a result, the flapping device of the present invention can minimize the number of wing support members while maintaining the rigidity of the wing support part, so that the wing can be rotated efficiently and accurate flight can be achieved at low cost. Here, in order to reduce inertia (moment of inertia), the wing shaft is preferably formed so that its diameter decreases in a tapered manner from the base end side to the tip end side (outside). As a result, the flapping device of the present invention can be expected to achieve more accurate flight.

[0016] Furthermore, the flapping device of the present invention includes a stopper that limits the rotation of the blade shaft to a predetermined rotation angle, and a limiter that is rotatably mounted integrally with the blade support member and limits the rotation of the blade shaft by contacting the stopper, thereby preventing the blade shaft from rotating beyond a predetermined range. In other words, since the blade shaft rotates within a predetermined range in the flapping device of the present invention, the angle of attack of the blades can be maintained within an appropriate range. Therefore, the flapping device of the present invention can stably generate lift force from the blades. Here, the rotation angle by the stopper can be set according to the twist angle of the blades, for example, it is preferable to set the rotation angle to +45 degrees to -45 degrees. Also, since the tip side (outside) of the blade is prone to twist deformation, it is preferable to set the rotation angle by the stopper to a range of +37 degrees to -37 degrees, taking this into consideration. The blade support member also serves to hold the blade shaft. Therefore, the blade support member can extend the blade axis in a direction intersecting the blade axis (for example, in a perpendicular direction).

[0017] (4) In the flapping device described above, the legs are preferably characterized by having a gap.

[0018] The flapping wing device of the present invention, as described above, can be configured as in (4) above to reduce the weight of the legs and minimize the aerodynamic impact on flight. Therefore, even when legs are provided, the flapping wing device of the present invention can minimize the impact on lift and flight. Here, the gap should be formed into a shape that is easy to maintain strength, such as an equilateral triangle or a hexagon. The area of ​​the gap can be appropriately changed depending on the material used to form the legs.

[0019] (5) In the flapping device of the present invention described above, the leg portion is preferably characterized in that a solid portion is formed in the center.

[0020] The flapping device of the present invention described above, when configured as described in (5) above, can fill the gaps provided for weight reduction. This makes it possible to suppress discontinuity in movement across the gaps in the flapping device of the present invention. Here, the solid part can be formed in various shapes and sizes, but it is desirable that the outer shape be such that the balance of the movement of the flapping device is not disrupted. For example, the solid part may be formed such that the mesh of the gap becomes finer towards the center. This makes it possible to easily adjust the flapping force (lift force) (including the drive balance of the wings) and balance adjustments such as weight without flying the flapping device of the present invention by applying a lift force that is at the boundary of whether or not it will float until flapping begins.

[0021] (6) The flapping device of the present invention described above is characterized in that the first biasing member and the second biasing member are directly or indirectly connected to each other such that their biasing forces are in opposite directions, and the first biasing member and the second biasing member are narrowed in the direction opposite to the biasing direction by the amplitude of the stroke such that the center of the stroke related to the flapping of the blades coincides with the amplitude centers of the first biasing member and the second biasing member.

[0022] The flapping device described above, when configured as in (6) above, can make the restoring force of the nonlinear biasing member (e.g., a torsion spring) linear. Therefore, the flapping device of the present invention can balance the biasing force provided by the biasing member, allowing the blades to stroke stably. Furthermore, since the flapping device of the present invention can utilize the restoring forces of the first biasing member and the second biasing member in a linear manner, the first biasing member and the second biasing member can be made smaller or their spring constants reduced compared to the case where only one biasing member is used. Therefore, the flapping device of the present invention can easily reduce costs and adjust the restoring force of the biasing member.

[0023] Furthermore, by configuring the flapping device of the present invention as described in (6) above, the first biasing member and the second biasing member can be narrowed for use. Therefore, the flapping device of the present invention can obtain a stable restoring force when using a biasing member that experiences greater stress when opened, such as a torsion spring. In addition, the flapping device of the present invention is narrowed in the opposite direction to the biasing direction by the amplitude of the stroke, so that the center of the stroke related to flapping coincides with the amplitude centers of the first biasing member and the second biasing member, so that the stroke related to the flapping of the wings is performed symmetrically. Therefore, the flapping device of the present invention can perform the stroke related to the flapping of the wings in a well-balanced and stable manner. As a result, the flapping device of the present invention can improve the accuracy of lift-off and flight. Here, if the first biasing member and the second biasing member are torsion springs, it is desirable that each torsion spring is wound diagonally (sequentially). This is expected to have the effect of suppressing an increase in the height of the torsion spring.

[0024] (7) In the flapping device of the present invention described above, the first biasing member and the second biasing member are characterized in that one end is directly or indirectly connected to the main frame, and the other end is directly or indirectly connected to the driven part so as to be able to rotate integrally with the driven part.

[0025] The flapping device described above, when configured as in (7) above, can make the restoring force of the nonlinear biasing member (e.g., a torsion spring) linear. Therefore, the flapping device of the present invention can balance the biasing force provided by the biasing member, allowing the blades to stroke stably. Furthermore, since the flapping device of the present invention can utilize the restoring forces of the first biasing member and the second biasing member in a linear manner, the first biasing member and the second biasing member can be made smaller and their spring constants reduced compared to the case where only one biasing member is used. Therefore, the flapping device of the present invention can easily reduce costs and adjust the restoring force of the biasing member.

[0026] (8) In the flapping device of the present invention described above, the base of the blade has a fringe that holds the outer edge, and the base end of the fringe is connected to the tip end of the blade support member, and the other end is connected to the tip end of the blade shaft.

[0027] The flapping device of the present invention described above, when configured as described in (8) above, can efficiently generate the lift force produced by the blades without reinforcing the blades more than necessary. Here, the connection between the blade shaft and the edging portion can be made, for example, by providing an attachment with an insertion opening along the blade shaft and an insertion opening along the edging portion at the intersection of the blade shaft and the edging portion, and connecting the blade shaft and the edging portion via the attachment by adhesive or the like. The blade shaft can be made of carbon fiber reinforced plastic (also called CFRP) having an outer diameter of about 0.8 mm, for example, and the edging portion can be made of CFRP having an outer diameter of about 0.3 mm, for example.

[0028] (9) The flapping device of the present invention described above is preferably characterized in that it has an inertial measuring device, and the inertial measuring device is located at or near the center of gravity.

[0029] The flapping wing device of the present invention, as described above, can reduce the influence of the weight of the inertial measurement unit (IMU) by configuring it as described in (9) above. As a result, the flapping wing device of the present invention can stabilize flight and achieve highly accurate flight. Here, the inertial measurement unit can be, for example, a 6-axis gyro sensor. It is also possible to use a 3-axis geomagnetic sensor in conjunction with the inertial measurement unit. Furthermore, the inertial measurement unit can be, for example, one utilizing a microelectromechanical system (MEMS). When using a gyro sensor, it is desirable from the viewpoint of reducing drift to use one with a low vibration rectification error (VRE).

[0030] (10) The flapping wing device of the present invention described above comprises an image acquisition unit and at least one of a distance measurement unit and an altitude measurement unit, wherein the image acquisition unit is provided on the leg portion and is positioned so as not to interfere with the leg portion when acquiring images.

[0031] As described above, the flapping wing device of the present invention, configured as shown in (9) above, allows for weight balance and lift force balance to be achieved by the legs, and reliable image acquisition is possible with the image acquisition unit. Therefore, during lift (flight), the flapping wing device of the present invention can accurately measure its position using the image acquisition unit and at least one of the distance measurement unit and hardness measurement unit, and can perform flight with high accuracy.

[0032] According to the present invention, it is possible to provide a flapping-wing device that can increase the power-to-weight ratio with a low-cost configuration and can be constructed in a compact size. Furthermore, the present invention can provide a flapping-wing device that can be easily adjusted in various ways.

[0033] This is an overall perspective view of a flapping device according to one embodiment of the present invention. This is a perspective view of a flapping device according to one embodiment of the present invention, viewed from the rear at an angle. This is a partially cutaway front view of a flapping device according to one embodiment of the present invention. This is a perspective view of a flapping device according to one embodiment of the present invention, viewed from the lower at an angle. This is a bottom view of a flapping device according to one embodiment of the present invention. This is a partially cutaway schematic configuration diagram of a flapping device according to one embodiment of the present invention. This is an explanatory front view of the legs of a flapping device according to one embodiment of the present invention. This is an explanatory plan view of a biasing member used in a flapping device according to one embodiment of the present invention. (a) is a screen diagram showing an example of the operation screen of an application used to operate the flapping device of the present invention, and (b) is an explanatory diagram of the command assignment assigned to the screen diagram in (a). This is a screen diagram showing an example of the operation screen of a controller (smartphone) used to operate the flapping device of the present invention.

[0034] The details of the flapping device 1 according to one embodiment of the present invention will be described below with reference to the attached drawings. Note that these drawings are schematic and do not necessarily represent the sizes in exact proportions. Also note that similar components are denoted by the same reference numerals in the drawings. Furthermore, as shown in Figure 1, the vertical direction in the drawing is sometimes referred to as the Z direction, the horizontal direction as the X direction, and the depth direction as the Y direction. Rotation around the Z axis is sometimes referred to as the yaw direction, rotation around the X axis as the pitch direction, and rotation around the Y axis as the roll direction. Also note that in Figure 1, the upper support portion 7U of the main frame 7 is omitted. Also note that in Figure 6, the suspension portion 72 and leg portion 75, etc., are omitted.

[0035] As shown in Figures 1 to 4, the flapping device 1 has a pair of blades 2, 2 and drive units 3, 3 provided for each of the pair of blades 2, 2. The drive units 3, 3 are supported on the main frame 7 so as to correspond to the pair of blades 2, 2. In this embodiment, the flapping device 1 obtains an upward lift force by reciprocating and oscillating the pair of blades 2, 2 in the horizontal direction (front-to-back direction in the illustration). Since the pair of blades 2, 2 and the pair of drive units 3, 3 are arranged symmetrically, in the following description, unless there is a particular need to distinguish between them, one side (right side) will be described and the other side (left side) will be omitted. Also, please note that in Figures 1 to 4, the illustrated upper side may be described as the upper side (U side) and the illustrated lower side as the lower side (D side).

[0036] The main frame 7 includes a pair of support parts 7U and 7D (see Figure 2) that are spaced apart in the vertical direction. In this embodiment, the main frame 7 (support parts 7U and 7D) is formed from plate-shaped members made of aluminum. The main frame 7 also rotatably supports a pair of driven parts 10, 10, which will be described later, and supports a pair of drive sources 30, 30. A first retaining member 70 extending downward is provided on the lower side of the support part 7U.

[0037] Furthermore, as will be described in more detail later, the main frame 7 is equipped with a suspension portion 72 and leg portions 75, etc., on the lower side of the lower support portion 7D.

[0038] As shown in Figure 1, the first retaining member 70 has a pair of holes on its upper and lower ends, into which one end of the first biasing member 40 and the second biasing member 41, described later, can be inserted. The first retaining member 70 is made of one or more members, for example, aluminum. In this embodiment, the hole on the upper end is located towards the rear in the Y direction (towards the back of the paper), and one upper end of the first biasing member 40 is inserted into this upper end hole. Also in this embodiment, the hole on the lower end is located towards the front in the Y direction (towards the front of the paper), and one upper end of the second biasing member 41 is inserted into this lower end hole. One end of the first biasing member 40 and the second biasing member 41 inserted into each hole of the first retaining member 70 is fixed, for example, by adhesive. This suppresses twisting around the wire of the first biasing member 40 and the second biasing member 41. The first holding member 70 may be formed integrally, or it may be formed separately for each of the first biasing member 40 and the second biasing member 41, for example.

[0039] As shown in Figures 1 to 4, the drive unit 3 includes a drive source 30, a driven unit 10, a first biasing member 40, a second biasing member 41, etc. A control unit 60 that controls the drive of the drive source 30 is connected to the drive unit 3. The drive source 30 is, for example, an in-runner type brushless DC motor. However, the drive source 30 is not limited to this and various types of motors can be used. The battery 4 for driving the drive source 30 is held in a suspension part 72, which will be described later, provided on the lower side of the main body frame 7. The battery 4 can be, for example, a rechargeable lithium-ion battery or a nickel-metal hydride battery. A power supply board 65 is also connected to the battery 4. The power supply board 65 can boost the battery voltage (for example, 4.2V when fully charged, 3.7V under normal conditions, and decreases due to internal resistance if the discharge current is large) to a constant voltage (for example, 13.5V). Furthermore, the power supply circuit of the power supply board 65 is connected to the control unit 60 with, for example, three wires: GND, power supply for the control circuit (for example, 3.3V), and power supply for the motor drive circuit (for example, 13.5V). Power is supplied through these wires. As a result, even if the voltage of the battery 4 changes, the voltage supplied from the power supply board 65 can be kept constant, allowing power control to be performed without considering changes in the power supply voltage during motor control. Therefore, control can be simplified.

[0040] The drive source 30 is supported on the outer surface of the support portion 7U located on the upper side. In this embodiment, the pair of drive sources 30, 30 are arranged symmetrically with respect to the center line C (see Figure 6).

[0041] Furthermore, the motor acting as the drive source 30 is equipped with ball bearings (not shown) at both ends of the motor housing to maintain the axial runout of the drive shaft 32. To further suppress axial runout, as shown in Figure 6, the drive shaft 32 of the drive source 30 may be rotatably supported on the support parts 7U and 7D via appropriate bearings (not shown). The tip end of the drive shaft 32 is also rotatably supported on the support part 7D via appropriate bearings (not shown). In addition, a drive gear 15, which acts as a pinion gear, is fitted onto the middle section of the drive shaft 32.

[0042] As shown in Figures 1 and 2, the driven part 10 is formed from a spur gear with a portion cut out. The cut-out portion of the driven part 10 is formed to suppress interference with the blades 2, etc. The driven part 10 has multiple circular holes formed in it as needed to reduce weight. Note that the holes may be provided as necessary. The driven part 10 is supported by the support part 7U so as to be rotatable in the direction of the axis of the first pivot shaft 11. Specifically, in this embodiment, the first pivot shaft 11 is rotatably supported by the support part 7U and the support part 7D, and the driven part 10 is fixed to the first pivot shaft 11 by press-fitting or the like. Also, in this embodiment, the driven part 10 is positioned closer to the support part 7D side (downward side). The driven part 10 is meshed with the drive gear 15 and is rotatable in the direction around the axis of the first pivot shaft 11 (see Figures 1 and 6) (also referred to as the direction around the first axis) by receiving power output from the drive source 30.

[0043] The driven part 10 is supported by a blade shaft holding part 50 for holding the blade shaft 20, which will be described later. The blade shaft holding part 50 is designed to rotate integrally with the driven part 10 in the direction of the first axis. The driven part 10 is provided with a second holding member 71 that holds the other end (rear end) of the first biasing member 40 and the second biasing member 41, which will be described later. A limiter 12 is also provided on the driven part 10 adjacent to the blade shaft holding part 50.

[0044] The second holding member 71 is formed in an L-shape using a material such as aluminum, and is erected above the driven portion 10. The second holding member 71 has a pair of holes on the upper end side and the base end side, and one end of each of a first biasing member 40 and a second biasing member 41, which will be described later, can be inserted into each of the pair of holes. In the present embodiment, the hole on the upper end side is provided closer to the rear side in the Y direction, and one end on the lower side of the first biasing member 40 is inserted into the hole on the upper end side. Further, in the present embodiment, the hole on the base end side is provided closer to the front side in the Y direction (the front side of the drawing), and one end on the lower side of the second biasing member 41 is inserted into the hole on the base end side. One ends of the first biasing member 40 and the second biasing member 41 inserted into the respective holes of the first holding member 70 are fixed by, for example, adhesion or the like. This suppresses twisting of the first biasing member 40 and the second biasing member 41 around the wire rod. Note that the first holding member 70 may be formed integrally, or may be formed separately for each of the first biasing member 40 and the second biasing member 41, for example.

[0045] A bearing 51 is supported by the blade shaft holding portion 50 so as to face radially outward of the driven portion 10. In other words, the bearing 51 is supported by the driven portion 10 in a direction intersecting the first rotation shaft 11 (a direction orthogonal to the first rotation shaft 11 in the present embodiment, hereinafter also referred to as a direction around the second axis). A blade shaft 20, which will be described later, is supported by the bearing 51 so as to be rotatable in the direction around the second axis.

[0046] As shown in FIGS. 1 to 4, the first biasing member 40 and the second biasing member 41 are each formed of, for example, a torsion spring, and are disposed between the support portion 7U and the driven portion 10.

[0047] The first biasing member 40 is arranged around the axis of the first rotating shaft 11. The first biasing member 40 is configured to apply a biasing force to the driven portion 10 in a direction opposite to the rotating direction of the driven portion 10 as the driven portion 10 rotates. In the present embodiment, a right-handed torsion spring is used as the first biasing member 40. One end side (front end side) of the first biasing member 40 is connected to the support portion 7U via the first holding member 70, and the other end side (rear side) is connected to the driven portion 10 via the second holding member 71. Therefore, the first biasing member 40 can apply a biasing force in a direction opposite to the rotating direction of the driven portion 10 as the driven portion 10 rotates. Further, in the present embodiment, one end side and the other end side of the first biasing member 40 are connected to the first holding member 70 and the second holding member 71 such that they face each other in a 180-degree direction (opposite directions).

[0048] The second biasing member 41 is arranged around the axis of the first rotating shaft 11. The second biasing member 41 is configured to apply a biasing force to the driven portion 10 in a direction opposite to the biasing direction of the first biasing member 40. In the present embodiment, a left-handed torsion spring is used as the second biasing member 41. Further, one end side (front end side) of the first biasing member 40 is connected to the support portion 7U via the first holding member 70, and the other end side (rear side) is connected to the driven portion 10 via the second holding member 71. Therefore, the second biasing member 41 can apply a biasing force in a direction opposite to the rotating direction of the driven portion 10 as the driven portion 10 rotates. Further, since the second biasing member 41 (left-handed) is connected to the first biasing member 40 (right-handed) with the biasing direction reversed, the restoring forces of the first biasing member 40 and the second biasing member 41 exhibit linearity. Further, in the present embodiment, one end side and the other end side of the second biasing member 41 are connected to the first holding member 70 and the second holding member 71 such that they face each other in a 180-degree direction (opposite directions).

[0049] Here, details such as the narrowing direction of the first biasing member 40 and the second biasing member 41 will be described.

[0050] As described above, the first biasing member 40 and the second biasing member 41 are connected directly or indirectly such that their biasing forces are in opposite directions (see Figure 3). In this embodiment, the torsion springs used in the first biasing member 40 and the second biasing member 41 are arranged in a diagonally wound (directly wound) state (see Figure 3). Therefore, the first biasing member 40 and the second biasing member 41 do not increase in height. This allows for miniaturization of the flapping device 1.

[0051] Furthermore, when using a torsion spring, the stress in the direction that opens both ends of the spring in the circumferential direction is usually high, so it is desirable to use the spring with both ends narrowed in the direction that closes in the circumferential direction. For this reason, in this embodiment, as shown in Figure 8, the first biasing member 40 and the second biasing member 41 are narrowed in the opposite direction to the biasing direction by the amplitude of the stroke, so that the center of the stroke related to the flapping of the blade 2 coincides with the amplitude centers of the first biasing member 40 and the second biasing member 41. In other words, in this embodiment, as described above, both ends of the first biasing member 40 are narrowed and connected so that they face 180 degrees apart from each other (position indicated by the dashed line in the figure).

[0052] As shown in Figures 1 to 4, the blade 2 has a blade shaft 20, a blade support member 21, a blade body 22, and a rim portion 23, etc.

[0053] The blade shaft 20 is formed to extend in the direction of a second axis intersecting the first axis (in this embodiment, the radial direction of the first pivot shaft 11). The blade shaft 20 is made of, for example, carbon fiber reinforced plastic (CFRP) with an outer diameter of 0.8 mm. In this embodiment, the blade shaft 20 is formed as a cylindrical rod, but the blade shaft 20 may be formed in a tapered shape that decreases in diameter towards the tip, taking inertia (moment of inertia) into consideration. Specifically, a blade shaft 20 with an outer diameter of 0.9 to 1.0 mm at the base end and an outer diameter of 0.5 mm at the tip end is preferably used.

[0054] Furthermore, one end (base end) of the blade shaft 20 is connected to the driven unit 10 via a blade shaft holding portion 50 and a bearing 51. Specifically, the blade shaft holding portion 50 includes a plate portion fastened to the gear of the driven unit 10 and a bearing holding portion that rises vertically from the plate portion. The blade shaft 20 is connected so as to be rotatable around the second axis. Specifically, at one end, the blade shaft 20 is rotatably supported by the bearing 51 of the blade shaft holding portion 50. Therefore, the blade shaft 20 can rotate in the direction of the first axis and the direction of the second axis. In addition, as the driven unit 10 rotates, the blade shaft 20 is subjected to a biasing force by the first biasing member 40 and the second biasing member 41 in the direction opposite to the direction of rotation. As a result, the blade shaft 20 is excited in the direction of rotation of the driven unit 10 (the direction of the first axis). Furthermore, a stopper 25, which will be described later, is provided at the base end of the blade shaft 20.

[0055] The blade support member 21 extends from the base end side (driven part 10 side) of the blade shaft 20 in a direction intersecting the blade shaft 20 (in this embodiment, the Z direction and the vertical direction), and is connected to the blade shaft 20 so as to be integrally rotatable. In other words, in this embodiment, the blade support member 21 also serves to hold the edging portion 23. By rotating integrally with the blade shaft 20, the angle of attack of the blade body 22 can be changed. The blade support member 21 is formed from a material such as aluminum and has fatigue strength to withstand the wind force when the blade 2 is flapped and the biasing force when the blade 2 is excited.

[0056] As shown in Figures 1 and 2, the limiter 12 is rotatably mounted integrally with the driven part 10 around the first pivot shaft 11 (first axis). The limiter 12 is formed of, for example, a plate-shaped member and has a substantially fan-shaped notch 12A formed symmetrically with respect to the blade shaft 20. The inclination angle (rise angle) of the notch 12A is, for example, -53 degrees and +53 degrees. That is, the notch 12A is cut in the range of -37 degrees to +37 degrees. The limiter 12 can limit the rotation angle of the blade shaft 20 by engaging with the stopper 25, which will be described later. The inclination angle of the notch 12A can be changed as appropriate.

[0057] The stopper 25 is fixed to a position corresponding to the stopper 25 on the base end side of the blade shaft 20. Therefore, the stopper 25 can rotate integrally with the blade shaft 20. The stopper 25 is formed in a block shape and is rotatably supported by a notch 12A in the stopper 25. As the stopper 25 rotates, it contacts (strikes) the limiter 12 at a predetermined angle, thereby limiting the rotation of the blade shaft 20 to a predetermined rotation angle. Here, the rotation angle by the stopper 25 can be set according to the twist angle of the blade 2, for example, it is good to set the rotation angle to be in the range of +45 degrees to -45 degrees. Also, since the rotation angle by the stopper is prone to twist deformation on the tip side (outside) of the blade, it is good to set it to be in the range of +37 degrees to -37 degrees, taking this into consideration. Thus, the flapping device 1 described above can prevent the blade support member 21 from rotating beyond a predetermined rotation angle, even when the blade support member 21 rotates around the first axis.

[0058] The blade body 22 is formed from a sheet-like member (for example, a composite fabric (DCF) manufactured by Dyneema®) which is made by laminating fibers made of ultra-high molecular weight polyethylene with a resin film made of polyester or polytetrafluoroethylene. The blade body 22 is supported by the blade shaft 20 and the blade support member 21 and can rotate integrally with the blade shaft 20. In other words, the blade body 22 is formed to extend in the longitudinal direction along the blade shaft 20 and to spread in the transverse direction along the blade support member 21. Furthermore, the lower outer edge of the blade body 22 on the side opposite to the upper outer edge along the blade shaft 20 (the lower end side shown in the figure) is curved in a roughly fan shape. The lower outer edge of the blade shaft 20 is held by the edging portion 23. The blade body 22 can reciprocate and generate levitation force by being driven by the drive source 30. The blade body 22 is bonded to the blade shaft 20 and the blade support member 21 with an adhesive or the like.

[0059] The edging portion 23 is connected at its base end to the tip end of the blade support member 21, and at its other end to the tip end of the blade shaft 20. The edging portion 23 is shaped to follow the lower outer edge of the blade body 22 and can hold the blade body 22. The edging portion 23 is made of, for example, carbon fiber reinforced plastic. The outer diameter of the edging portion 23 is smaller than that of the blade shaft 20 (0.3 mm in this embodiment). The blade body 22 is bonded to the edging portion 23 with an adhesive or the like. An attachment 24 is provided on the tip end of the edging portion 23 (blade shaft 20). In addition, as the driven portion 10 rotates, the edging portion 23, together with the blade shaft 20 and the blade support member 21, is subjected to a biasing force by the first biasing member 40 in the opposite direction to the rotation direction. Furthermore, the edging portion 23 rotates together with the blade support member 21 around the blade shaft 20 (second axis) due to the wind pressure received by the blade body 22.

[0060] The attachment 24 is intended to connect the blade shaft 20 and the edging portion 23. The attachment 24 has an insertion opening along the blade shaft 20 and an insertion opening along the edging portion 23, and is provided at the intersection of the blade shaft 20 and the edging portion 23. The blade shaft 20 and the edging portion 23 are connected by inserting the respective ends of the blade shaft 20 and the edging portion 23 into the attachment 24. The connection between the blade shaft 20 and the edging portion 23 and the attachment 24 should preferably be made by adhesive or the like.

[0061] Next, we will describe in detail the suspension portion 72 and the leg portion 75, which are located on the lower side of the main frame 7.

[0062] As shown in Figure 3, the suspension portion 72 is suspended below the support portion 7D in the main frame 7. The suspension portion 72 has two pairs of left and right support columns 72A, 72A, 72A, 72A (hereinafter also collectively referred to simply as support columns 72A), an intermediate support frame 72B supported in the middle of the support columns 72A, and a bottom frame 72C supported at the bottom of the support columns 72A, etc.

[0063] An inertial measurement device 61 is provided on the lower surface of the intermediate support frame 72B. The inertial measurement device 61 is also called an IMU (Inertial Measurement Unit). For example, a 6-axis gyro sensor can be used for the inertial measurement device 61. The inertial measurement device 61 can measure the translational acceleration and rotational speed of the flapping device 1. The inertial measurement device 61 is positioned at or near the center of gravity. Therefore, the inertial measurement device 61 can perform measurements while minimizing the influence of the centrifugal force generated by the rotational motion of the flapping device 1 on the translational acceleration measurement.

[0064] The inertial measurement device 61 can also utilize a three-axis or other geomagnetic sensor. Furthermore, the inertial measurement device 61 can utilize, for example, a micro-electromechanical system (MEMS). When using a gyro sensor, it is desirable to use one with a low vibration rectification error (VRE) from the viewpoint of reducing drift. A damper to reduce vibration can also be provided between the inertial measurement device 61 and the intermediate support frame 72B. A damper is preferably used when the flapping frequency and the fuselage control frequency are far apart. This is to avoid the disappearance or attenuation of the fuselage control frequency required for control when the flapping frequency is attenuated.

[0065] As shown in Figure 5, a battery 4, a control unit 60, and an image acquisition unit 62 are provided on the underside of the base frame 72C. At least one of a distance measuring unit 63 and an altitude measuring unit 64 is also provided on the underside of the base frame 72C. Furthermore, as shown in Figure 7, a leg portion 75 is provided on the lower end of the suspension portion 72 (the underside of the base frame 72C).

[0066] As shown in Figure 1, the control unit 60 controls the output of the driving force from the drive source 30. That is, by controlling the output of the driving force from the drive source 30, a predetermined reciprocating motion is imparted to the blade 2. The control unit 60 can control the output of the driving force from the drive source 30 based on numerical values ​​and images measured by the inertial measuring device 61, image acquisition unit 62, distance measuring unit 63, altitude measuring unit 64, etc., which will be described later. In addition, the control unit 60 can communicate with a controller (not shown) or a smartphone 5 (see Figures 9 and 10) and perform control based on their commands.

[0067] As shown in Figures 3 and 5, the image acquisition unit 62 can acquire images of the underside of the flapping wing device 1 by imaging with a camera or the like. As shown in Figure 5, the image acquisition unit 62 is positioned to avoid interference with the leg portion 75, which will be described later, and is located at a position corresponding to the opening 76 in the leg portion 75. By analyzing the acquired images, the image acquisition unit 62 can measure at least the amount of movement in the horizontal direction.

[0068] For example, a Time of Flight (ToF) sensor is used in the distance measurement unit 63. A ToF sensor measures the distance to an object by measuring the time it takes for light emitted from a light source to reflect off the object and return. As a result, the height can be obtained through the distance measurement unit 63.

[0069] For example, a barometric pressure sensor is used in the altitude measurement unit 64. The barometric pressure sensor can determine the absolute altitude of the flapping device 1 based on changes in atmospheric pressure.

[0070] Here, the distance measuring unit 63 and the altitude measuring unit 64 can be provided individually or in combination. The decision of which of the distance measuring unit 63 and the altitude measuring unit 64 to install, or to install both, should be made by considering measurement accuracy, cost, weight, etc.

[0071] As shown in Figure 3, the leg portion 75 is suspended from the support column 72A. As shown in Figure 7, the leg portion 75 is formed in a spherical shell shape that forms part of the sphere 8. The leg portion 75 has a mesh-like void portion 77. In this embodiment, the void portion 77 is formed in the shape of an equilateral triangle (see Figure 5). The shape of the void portion 77 can be formed in various shapes (for example, circular, rectangular, pentagonal, etc.). Furthermore, although the void portion 77 is not limited, it is desirable to have a structure that can maintain strength, such as a honeycomb shape such as a hexagon. Various sizes of voids in the void portion 77 can be used, but from the viewpoint of weight reduction, it is desirable to make them as large as possible while maintaining strength. Also, as shown in Figure 5, the leg portion 75 has a spherical shell-shaped solid portion 78 in the center that does not have a void portion 77. The solid portion 78 is designed to fill the gaps provided for weight reduction, thereby preventing discontinuity in the movement of the flapping device 1 across the gaps 77. The solid portion 78 can be formed in various shapes and sizes, but it is desirable that its outer shape be such that it does not disrupt the balance of the movement of the flapping device 1. For example, the solid portion 78 may be formed such that the mesh of the gaps 77 becomes finer towards the center. In this embodiment, the solid portion 78 is formed in a circular shape in plan view, with a portion of the part that overlaps with the opening 76 for the image acquisition unit 62 being cut out.

[0072] Here, the sphere 8 forming part of the leg portion 75 is preferably a sphere with a diameter at least equal to the diameter passing through the lowest point of the wings 2, 2 when the flapping device 1 is viewed from the front, as shown in Figure 7. Furthermore, it is preferable that the leg portion 75 has a diameter equal to the distance between the base ends of the pair of wing shafts 20 when viewed from below (see Figure 5). As a result, the flapping device 1 of the present invention can suppress tipping over without making the leg portion 75 unnecessarily large. In other words, by utilizing the spherical surface of the leg portion 75, the flapping device 1 of the present invention can effectively suppress tipping over when placed on the ground or the like, as the device body swings.

[0073] The above describes the configuration of the flapping device 1 according to one embodiment of the present invention. Note that the configuration of the parts arranged symmetrically on the left and right sides is the same as described above, so its explanation is omitted.

[0074] Next, a method for adjusting the flapping device 1 using the leg portion 75 will be described. In this embodiment, an example is given in which the flapping device 1 is controlled (adjusted) using an operating application installed on the smartphone 5 shown in Figure 10.

[0075] Figure 9(a) shows the smartphone 5 in landscape orientation with the adjustment controller displayed on the screen. On the left side of the screen, in this embodiment, operation buttons 80 are displayed to which command assignments (e.g., roll, pitch, yaw, etc.) as shown in Figure 9(b) are assigned. The flapping device 1 can control its lift force, direction, etc. by operating the operation buttons 80.

[0076] To adjust the flapping device 1, first, the flapping device 1 is placed on a flat surface such as the ground or a table. Next, the drive source 30 is driven to generate a lift force near the boundary between whether or not the flapping device 1 will lift off.

[0077] Figure 10 shows the state (balance) of the flapping device 1 displayed on the screen of the smartphone 5. Here, the mismatch in the lifting forces on the left and right sides of the flapping device 1 causes the flapping device 1 to tilt to the left and right. In addition, the deviation of the center of the flapping stroke to the front and back causes the flapping device 1 to tilt to the front and back. Furthermore, the mismatch in the flapping speed and angle of attack in each stroke of the flapping device 1 causes a deviation in the direction of the flow velocity from the vertically downward direction, resulting in rotation of the flapping device 1 around its vertical axis. Therefore, the point where these movements do not occur can be considered the neutral point, that is, the point where the steering torque around all axes of roll, pitch, and yaw is 0 (zero). More specifically, the motor drive power for the left and right flapping motion that does not cause the left-right tilt described above, the average value of the motor drive voltage that does not cause the front-back tilt, and the difference in flapping time between the left and right wings in the forward and backward directions (Split Cycle Factor) that does not cause rotation around the vertical axis are defined as the neutral points for roll, pitch, and yaw, respectively.

[0078] The state of the flapping device 1 can be any value that represents the motion of the flapping device 1 due to steering torque caused by fluid force. Here, as an example, the roll and pitch attitude angles obtained from the inertial measuring device 61 mounted on the flapping device 1 are shown as points M, represented by the Roll and Pitch coordinate axes in Figure 10, respectively. Similarly, the rotational angular velocity around the yaw axis measured by the inertial measuring device 61 is shown as point M, positioned according to the value of the Yaw axis in Figure 10. The Height value is zero because the device is not levitating, but the drive power may be used as the coordinate value.

[0079] Next, while receiving data related to the deviation of the neutral point NP in real time via the smartphone 5, the operator moves the marker M (point M) on the screen onto the neutral point NP, for example, by dragging it. As a result, a correction value is automatically calculated so that the flapping device 1 approaches the neutral point NP, and a command is sent to the control unit 60. This corrects the balance of the flapping device 1, such as the lift force. Note that the screen configuration of the application is not limited to this embodiment, and various screen configurations can be adopted, and various items can be set for operation commands, etc. In order to improve the accuracy of the adjustment of the flapping device 1, it is desirable to correct the deviation from the neutral point NP according to the lift force in multiple stages. Here, since the position of the neutral point NP is also shifted by the motor power, it is advisable to derive the neutral point NP from two points that do not cause lift and use a method of linear interpolation. For example, if we assume that the system floats at 80% output, we can find the neutral point NP at 60% and 70% output respectively, and then use linear interpolation to calculate the neutral point NP at output levels above 80%.

[0080] The above describes one embodiment of the flapping device 1 of the present invention. Next, the effects and advantages realized by the flapping device 1 of the present invention will be described in detail below.

[0081] The flapping device 1 of the present invention described above has the following characteristic configurations (a) to (j). Therefore, the flapping device 1 of the present invention can produce unique effects that cannot be achieved with the prior art, as described below.

[0082] (a) The flapping device 1 of this embodiment described above comprises a pair of blades 2, 2 and a drive unit 3 provided corresponding to each of the pair of blades 2, 2, wherein the drive unit 3 comprises a drive source 30, a driven part 10 that rotates around a first axis by receiving power output from the drive source 30, a first biasing member 40 that applies a biasing force to the driven part 10 in the opposite direction to the rotation direction of the driven part 10 as the driven part 10 rotates, a second biasing member 41 that applies a biasing force to the driven part 10 in the opposite direction to the biasing direction of the first biasing member 40, and a control unit 60 that controls the output of the driving force from the drive source 30, wherein the blades 2 extend in the direction of a second axis intersecting the first axis The device also comprises a blade shaft 20 connected to the driven part 10 at one end and rotatably connected around the second axis, a blade support member 21 extending in a direction intersecting the blade shaft 20 at the base end of the blade shaft 20 and rotatably connected integrally with the blade shaft 20, and a blade body 22 supported by the blade shaft 20 and the blade support member 21 and rotatably connected integrally with the blade shaft 20, a main body frame 7 that rotatably supports at least the driven part 10 and supports the drive source 30, a suspension part 72 suspended below the main body frame 7, and a spherical shell-shaped leg part 75 provided on the lower end of the suspension part 72 and forming part of the sphere 8.

[0083] In the flapping device 1 of this embodiment described above, the first biasing member 40 and the second biasing member 41 can apply biasing forces to the driven part 10 in opposite directions, thus linearizing the restoring forces of the first biasing member 40 and the second biasing member 41. Therefore, the flapping device 1 of this embodiment can distribute the stroke related to the flapping of the blades 2 in a balanced and symmetrical manner. As a result, the flapping device 1 of this embodiment can stabilize the lift and flight, thereby improving flight accuracy. Furthermore, the flapping device 1 of this embodiment can excite the blade shaft 20 in the direction around the first axis by the biasing of the first biasing member 40 and the second biasing member 41. Therefore, the flapping device 1 of this embodiment can amplify the flapping frequency of the pair of blades 2, 2 by excitation, so the pair of blades 2, 2 can be driven at high speed. As a result, a strong lift force can be obtained. Here, the first biasing member 40 and the second biasing member 41 are preferably made of materials that can bias in the torsional direction, such as torsion springs. The main frame 7 is preferably made of aluminum, for example. This ensures sufficient rigidity to withstand the biasing force from the first biasing member 40 and the second biasing member 41 and the load from the flapping of the blades 2, 2, while also suppressing an increase in the weight of the main body of the device.

[0084] Furthermore, since the flapping-wing device 1 of this embodiment can independently drive and control each of the pair of drive sources 30, it is possible to fly in various directions. Here, various types of motors can be used for the drive source 30, but a brushless DC motor that can easily rotate in both forward and reverse directions and has a high power-to-weight ratio is preferably used. This makes battery operation easy and control can be easily performed.

[0085] Furthermore, the flapping device 1 of this embodiment is equipped with a spherical shell-shaped leg portion 75 that forms part of the sphere 8 at the lower end of the suspension portion 72 on the lower side of the main frame 7. Therefore, when the flapping device 1 of this embodiment is placed on the ground or a table, the leg portion 75 can prevent it from tipping over. In addition, since the main body of the flapping device 1 of this embodiment can be supported by the leg portion 75, it is possible to adjust the lift force (such as adjusting the flapping stroke) and the weight balance while applying lift force near the boundary of whether or not it will lift off. Therefore, the flapping device 1 of this embodiment can be adjusted quickly without having to fly it each time an adjustment is made.

[0086] Here, adjustments can be made using various sensors provided by the flapping device 1. For example, it is desirable to measure the left and right drive voltage balance (corresponding to roll), the drive voltage offset of both blades 2, 2 (corresponding to pitch), the Split Cycle Factor (corresponding to yaw), etc., and adjust them so that each reaches a neutral point. Furthermore, since the above adjustments change with the driving force, it is desirable to measure at multiple driving forces and supplement the adjustment amount by prediction. Here, it is desirable that the sphere 8 that forms part of the leg portion 75 is a sphere 8 with a diameter at least that passes through the lowest point of the blades 2, 2 when the flapping device 1 is viewed from the front. Furthermore, it is desirable that the leg portion 75 has a diameter between the base ends of the pair of blade shafts 20 when viewed from below. By doing so, the flapping device 1 of this embodiment can suppress the tipping of the device body without making the leg portion 75 unnecessarily large. In other words, the flapping device 1 of this embodiment utilizes the spherical surface of the leg portion 75, causing the device body to oscillate when placed on the ground or the like, thus effectively suppressing tipping over.

[0087] (b) The flapping device 1 of this embodiment described above is characterized by having a stopper 25 that limits the rotation of the blade shaft 20 to a predetermined rotation angle, and a limiter 12 that is provided so as to be rotatable integrally with the blade support member 21 and limits the rotation of the blade shaft 20 by contacting the stopper 25.

[0088] The flapping device 1 of this embodiment, as described above, can suppress the rotation of the blade shaft 20 beyond a predetermined range by being configured as shown in (b) above. In other words, in the flapping device 1 of this embodiment, the blade shaft 20 rotates within a predetermined range, so the angle of attack of the blades 2 can be maintained within an appropriate range. Therefore, the flapping device 1 of this embodiment can stably generate lift force from the blades 2, 2. Here, the rotation angle by the stopper 25 can be set according to the twist angle of the blades 2, 2, for example, it is good to set the rotation angle to +45 degrees to -45 degrees. Also, since the tip side (outside) of the blades 2, 2 is prone to twist deformation, it is good to set the rotation angle by the stopper 25 to be in the range of +37 degrees to -37 degrees, taking this into consideration.

[0089] (c) The flapping device 1 of this embodiment described above comprises a pair of blades 2, 2 and a drive unit 3 provided corresponding to each of the pair of blades 2, 2, wherein the drive unit 3 comprises a drive source 30, a driven part 10 that rotates around a first axis by receiving power output from the drive source 30, a first biasing member 40 that applies a biasing force to the driven part 10 in the opposite direction to the rotation direction of the driven part 10 in conjunction with the rotation of the driven part 10, a second biasing member 41 that applies a biasing force to the driven part 10 in the opposite direction to the biasing direction of the first biasing member 40, and a control unit 60 that controls the output of the driving force from the drive source 30, wherein the blades 2, 2 extend in the direction of a second axis intersecting the first axis The invention also comprises a blade shaft 20 connected to a driven part 10 at one end and rotatably connected around the second axis, a blade support member 21 extending in a direction intersecting the blade shaft 20 at the base end of the blade shaft 20 and rotatably connected integrally with the blade shaft 20, and a blade body 22 supported by the blade shaft 20 and the blade support member 21 and rotatably connected integrally with the blade shaft 20, a stopper 25 that limits the rotation of the blade shaft 20 to a predetermined rotation angle, and a limiter 12 that is rotatably provided integrally with the blade support member 21 and limits the rotation of the blade shaft 20 by contacting the stopper 25.

[0090] In the flapping device 1 of this embodiment described above, the blade support member 21 provided on the base end side of the blade shaft 20 rotates together with the blade shaft 20, so that the blade 2 can be rotated while supporting the inner end of the blade body 22. Therefore, in the flapping device 1 of this embodiment, the blade 2 can be rotated around the blade shaft 20 while the longitudinal direction of the blade body 22 is supported by the blade shaft 20 and the short direction of the blade body 22 is supported by the blade support member 21. As a result, the flapping device 1 of this embodiment can minimize the support member for the blade 2 while maintaining the rigidity of the support part of the blade 2, so that the blade 2 can be rotated efficiently and accurate flight can be achieved at low cost. Here, in order to reduce the inertia (moment of inertia), the blade shaft 20 is preferably formed so that its diameter decreases in a tapered manner from the base end side to the tip side (outside). As a result, the flapping device 1 of this embodiment can be expected to achieve more accurate flight.

[0091] Furthermore, the flapping device 1 of this embodiment includes a stopper 25 that limits the rotation of the blade shaft 20 to a predetermined rotation angle, and a limiter 12 that is rotatably mounted integrally with the blade support member 21 and limits the rotation of the blade shaft 20 by contacting the stopper 25. Therefore, it is possible to suppress the rotation of the blade shaft 20 beyond a predetermined range. In other words, in the flapping device 1 of this embodiment, since the blade shaft 20 rotates within a predetermined range, the angle of attack of the blade 2 can be maintained within an appropriate range. Therefore, the flapping device 1 of this embodiment can stably generate lift force from the blade 2. Here, the rotation angle by the stopper 25 can be set according to the twist angle of the blade 2, for example, it is good to set the rotation angle to +45 degrees to -45 degrees. Also, since the tip side (outside) of the blade 2 is prone to twist deformation, it is good to set the rotation angle by the stopper 25 to a range of +37 degrees to -37 degrees, taking this into consideration. Furthermore, the blade support member 21 also serves to hold the blade shaft 20. Therefore, the blade support member 21 can extend the blade shaft 20 in a direction intersecting the blade shaft 20 (for example, in a perpendicular direction).

[0092] (d) The flapping device 1 described above is characterized in that the leg portion 75 has a gap portion 77.

[0093] The flapping wing device 1 of this embodiment, as described above, can be configured as shown in (d) above to reduce the weight of the legs 75 and minimize the aerodynamic impact on flight. Therefore, even when the legs 75 are provided, the flapping wing device 1 of this embodiment can minimize the impact on lift and flight. Here, the gap 77 should be formed into a shape that is easy to maintain strength, such as an equilateral triangle or a hexagon. The area of ​​the gap 77 can be appropriately changed depending on the material used to form the legs 75.

[0094] (e) In the flapping device 1 of this embodiment described above, the leg portion 75 is characterized in that a solid portion 78 is formed in the center.

[0095] The flapping device of this embodiment described above can be configured as shown in (e) above to fill the gap 77 provided for weight reduction. As a result, the flapping device 1 of this embodiment can suppress discontinuity in movement across the gap 77. Here, the solid part 78 can be formed in various shapes and sizes, but it is desirable that its outer shape be such that the balance of the movement of the flapping device 1 is not disrupted. For example, the solid part 78 may be formed such that the mesh of the gap 77 becomes finer towards the center. As a result, the flapping device 1 of this embodiment can be given a lift force at a level that is on the boundary of whether or not it will float, until flapping begins, and the flapping force (lift force) (including adjustment of the drive balance of the wings) and balance adjustments such as weight can be easily made without flying the device.

[0096] (f) The flapping device 1 of this embodiment described above is characterized in that the first biasing member 40 and the second biasing member 41 are directly or indirectly connected to each other such that their biasing forces are in opposite directions, and the first biasing member 40 and the second biasing member 41 are narrowed in the direction opposite to the biasing direction by the amplitude of the stroke such that the center of the stroke related to the flapping of the blade 2 coincides with the amplitude centers of the first biasing member 40 and the second biasing member 41.

[0097] The flapping device 1 described above, when configured as shown in (f) above, can make the restoring force of the nonlinear biasing member (for example, a torsion spring) linear. Therefore, the flapping device 1 of this embodiment can balance the biasing force provided by the biasing member, allowing the blades 2 to stroke stably. Furthermore, since the flapping device 1 of this embodiment can utilize the linear restoring forces of the first biasing member 40 and the second biasing member 41, the first biasing member 40 and the second biasing member 41 can be made smaller and their spring constants reduced compared to the case where only one biasing member is used. Therefore, the flapping device 1 of this embodiment can easily reduce costs and adjust the restoring force of the biasing member.

[0098] Furthermore, by configuring the flapping device 1 of this embodiment as described in (f) above, the first biasing member 40 and the second biasing member 41 can be narrowed for use. Therefore, the flapping device 1 of this embodiment can obtain a stable restoring force when using a biasing member that experiences greater stress when opened, such as a torsion spring. In addition, the flapping device 1 of this embodiment is narrowed in the opposite direction to the biasing direction by the amplitude of the stroke, so that the center of the stroke related to flapping coincides with the amplitude centers of the first biasing member 40 and the second biasing member 41, so that the stroke related to the flapping of the wing 2 is performed symmetrically. Therefore, the flapping device 1 of this embodiment can perform the stroke related to the flapping of the wing 2 in a well-balanced and stable manner. As a result, the flapping device 1 of this embodiment can improve the accuracy of lift-off and flight. Here, if the first biasing member 40 and the second biasing member 41 are torsion springs, it is desirable that each torsion spring is wound diagonally (sequentially). This is expected to have the effect of suppressing an increase in the height of the torsion spring.

[0099] (g) In the flapping device 1 of this embodiment described above, the first biasing member 40 and the second biasing member 41 are characterized in that one end is directly or indirectly connected to the main frame 7, and the other end is directly or indirectly connected to the driven part 10 so as to be able to rotate integrally with the driven part 10.

[0100] The flapping device 1 described above, when configured as shown in (g) above, can make the restoring force of the nonlinear biasing member (for example, a torsion spring) linear. Therefore, the flapping device 1 of this embodiment can balance the biasing force provided by the biasing member, allowing the blades 2 to stroke stably. Furthermore, since the flapping device 1 of this embodiment can utilize the linear restoring forces of the first biasing member 40 and the second biasing member 41, the first biasing member 40 and the second biasing member 41 can be made smaller and their spring constants reduced compared to the case where only one biasing member is used. Therefore, the flapping device 1 of this embodiment can easily reduce costs and adjust the restoring force of the biasing member.

[0101] (h) In the flapping device 1 of this embodiment described above, the blade body 22 has a fringe portion 23 that holds the outer edge, and the fringe portion 23 is characterized in that its base end is connected to the tip side of the blade support member 21 and its other end is connected to the tip side of the blade shaft 20.

[0102] The flapping device 1 of this embodiment described above, when configured as described in (h) above, can efficiently generate the lift force generated by the blades 2 without reinforcing the blades 2 more than necessary. Here, the connection between the blade shaft 20 and the edging portion 23 can be made, for example, by providing an attachment with an insertion opening along the blade shaft 20 and an insertion opening along the edging portion 23 at the intersection of the blade shaft 20 and the edging portion 23, and connecting the blade shaft 20 and the edging portion 23 via the attachment by adhesive or the like. The blade shaft 20 can be made of, for example, carbon fiber reinforced plastic (also called CFRP) having an outer diameter of about 0.8 mm, and the edging portion 23 can be made of, for example, CFRP having an outer diameter of about 0.3 mm.

[0103] (i) The flapping device 1 of this embodiment described above is characterized in that it has an inertial measuring device 61, and the inertial measuring device 61 is located at or near the center of gravity.

[0104] The flapping wing device 1 of this embodiment, as described above, can be configured as shown in (i) above to reduce the influence of the weight of the inertial measurement unit 61 (also called the IMU). As a result, the flapping wing device 1 of this embodiment can stabilize its flight and achieve highly accurate flight. Here, the inertial measurement unit 61 can be, for example, a 6-axis gyro sensor. It is also possible to use a 3-axis geomagnetic sensor in conjunction with the inertial measurement unit 61. Furthermore, the inertial measurement unit 61 can be, for example, one that utilizes a microelectromechanical system (MEMS). When using a gyro sensor, it is desirable to use one with a low vibration rectification error (VRE) from the viewpoint of reducing drift.

[0105] (j) The flapping wing device 1 of this embodiment described above comprises an image acquisition unit 62 and at least one of a distance measurement unit 63 and an altitude measurement unit 64, wherein the image acquisition unit 62 is provided on the leg portion 75 and is positioned so as not to interfere with the leg portion 75 when acquiring images.

[0106] As described above, the flapping wing device 1 of this embodiment, when configured as described in (i) above, can balance weight and lift force using the legs 75, and can reliably acquire images with the image acquisition unit 62. Therefore, during lift (flight), the flapping wing device 1 of this embodiment can accurately measure its position using the image acquisition unit 62 and at least one of the distance measurement unit 63 and the hardness measurement unit, and can also fly with high accuracy.

[0107] The above describes the configuration and effects of the flapping device 1 of the present invention. However, the flapping device 1 of the present invention is not limited to the embodiments or modifications described above, and various modifications can be made within the scope of the present invention. For example, the flapping device 1 of the present invention may be as described in (a) or (c) above, and can be formed in various shapes and sizes. Furthermore, the flapping device 1 of the present invention may, for example, not have some or all of the configurations described in (b), (d) to (j) above, or may have some or all of the configurations described in (b), (d) to (j) above, and other configurations.

[0108] For example, the pair of blades 2, 2 are not limited to those in the embodiment described above and can be formed in various shapes and sizes. Also, although a pair of blades 2, 2 are provided in this embodiment, the number of blades 2 can be changed as appropriate, for example, to two pairs. In such cases, additional drive sources 30, etc., can be added corresponding to the blades 2. Furthermore, the blade shaft 20, blade support member 21, and blade body 22 can be formed in various shapes and sizes, and the direction of formation can also be changed as appropriate. For example, the blade shaft 20 can be tapered, with the diameter decreasing towards the tip, as described above. Furthermore, the materials of the blade shaft 20, blade support member 21, and blade body 22 can also be changed in various ways.

[0109] Furthermore, although this embodiment illustrates the use of outrunner motors in DC motors as the drive sources 30, 30, various motors capable of generating driving force can be used as the drive sources 30, 30. For example, the drive sources 30, 30 may be composed of inrunner motors in DC motors.

[0110] Furthermore, in this embodiment, a spur gear is used for the driven part 10, and these are driven by a drive gear 15 which is a pinion gear, but the present invention is not limited to this. Various forms of driven parts 10 can be used. For example, the driven part 10 may be formed from a pulley or the like and driven by a belt or the like. Also, in accordance with the form of the driven part 10, the drive gear 15 can be of various forms other than just a gear. In addition, in this embodiment, integrated control is performed by a single control unit 60, but the control unit 60 may be composed of multiple units, such as separating the control for each function.

[0111] Furthermore, while torsion springs are used as the first biasing member 40 and the second biasing member 41 in this embodiment, the invention is not limited to this. Various types of biasing members can be used for the first biasing member 40 and the second biasing member 41, not just torsion springs. Also, while the same type of torsion spring is used for the first biasing member 40 and the second biasing member 41 in this embodiment, it is also possible to use different types of biasing members. In addition, the arrangement of the first biasing member 40 and the second biasing member 41 can be changed in various ways within the scope of the present invention. For example, the first biasing member 40 and the second biasing member 41 may be arranged separately above and below each other via the driven part 10. Also, while a pair of biasing members, the first biasing member 40 and the second biasing member 41, is used in this embodiment, biasing members can be used in various quantities. In such cases, it is desirable to use biasing members arranged and in quantities that can exhibit linearity.

[0112] Furthermore, although the embodiment is configured as described in (f) above, the throttling direction of the first biasing member 40 and the second biasing member 41, and the amount of throttling relative to the stroke of the flapping blade 2, can be changed in various ways.

[0113] Furthermore, although this embodiment illustrates a main frame 7 made of aluminum, the present invention is not limited to this, and the main frame 7 can be constructed using various materials (for example, metals such as iron, or various resins including fiber-reinforced plastics). Also, the main frame 7 may be made not only of one type of material, but also of a combination of multiple types of materials. In addition, the main frame 7 can be made of various shapes and sizes, not just those described above.

[0114] Furthermore, the suspension portion 72 may be provided as needed, and the leg portion 75 may be formed directly on the main frame 7 without the suspension portion 72. Also, when the suspension portion 72 is provided, the suspension portion 72 can be of various shapes, sizes, and materials. Also, the leg portion 75 may be provided as needed, and the configuration may be made without the leg portion 75. Also, although the leg portion 75 is made to form part of the sphere 8, it may be formed by an arc-shaped curvature that approximates the sphere 8. Also, the solid portion 78 of the leg portion 75 may be provided as needed, and the configuration may be made without the solid portion 78. Also, when the solid portion 78 is provided, the shape and size of the solid portion 78 can be made in various shapes and sizes. Also, the leg portion 75 may be made without a gap portion 77. When a gap portion 77 is provided in the leg portion 75, the gap portion 77 can be of various shapes, sizes, and materials.

[0115] Furthermore, the rotation angle limited by the stopper 25 and limiter 12 that restrict the rotation angle of the blade shaft 20 can be set to various angles. Also, various shapes, sizes, and materials can be used for the stopper 25 and limiter 12.

[0116] Furthermore, although a border portion 23 is provided in this embodiment, the border portion 23 may be provided only as needed, and a configuration without a border portion 23 is also possible. In addition, the border portion 23 can be of various shapes, sizes, and materials.

[0117] Furthermore, although a 6-axis gyro sensor is used as the inertial measuring device 61 in this embodiment, the inertial measuring device 61 is not limited to a 6-axis device; gyro sensors with various numbers of axes can be used. Also, the inertial measuring device 61 may consist of other sensors in addition to gyro sensors. In addition, there may be more than one inertial measuring device 61. Furthermore, when multiple inertial measuring devices 61 are used, each inertial measuring device 61 may be composed of the same type or a combination of different types. In addition, it is desirable to place the inertial measuring device 61 at or near the center of gravity, but it is not limited to this, and it can be placed at various positions.

[0118] Furthermore, the image acquisition unit 62, distance measurement unit 63, and altitude measurement unit 64 may be provided as needed, and when provided, various sensors, cameras, etc. can be used for the image acquisition unit 62, distance measurement unit 63, and altitude measurement unit 64. Also, various known methods can be used for analyzing the images acquired by the image acquisition unit 62. In addition, the inertial measuring device 61, distance measurement unit 63, and altitude measurement unit 64 may each be provided as needed, and when provided, the quantity, type, and combination can be changed as appropriate.

[0119] The above describes various embodiments and modifications of the flapping device 1 according to the present invention. However, the present invention is not limited to those exemplified in the embodiments and modifications described above, and it will be readily apparent to those skilled in the art that other embodiments may exist in the spirit and nature of the teachings, without departing from the scope of the claims.

[0120] The flapping wing device of the present invention can be used for various aerial surveys, repairs, photography, and other purposes.

[0121] 1: Flapping mechanism 2: Blade 3: Drive unit 7: Main frame 7D: Support part 7U: Support part 8: Sphere 10: Driven part 11: First rotation axis 12: Limiter 20: Blade shaft 21: Blade support member 22: Blade body 23: Edge part 25: Stopper 30: Drive source 40: First biasing member 41: Second biasing member 60: Control unit 61: Inertial measurement device 62: Image acquisition unit 63: Distance measurement unit 64: Altitude measurement unit 72: Suspension part 75: Leg part 77: Gap part 78: Solid part NP: Neutral point M: Marker (point)

Claims

1. A pair of blades, and a drive unit provided corresponding to each of the pair of blades, wherein the drive unit comprises a drive source, a driven part that rotates around a first axis upon receiving power output from the drive source, a first biasing member that applies a biasing force to the driven part in the opposite direction to the rotation direction of the driven part in conjunction with the rotation of the driven part, a second biasing member that applies a biasing force to the driven part in the opposite direction to the biasing direction of the first biasing member, and a control unit that controls the output of the driving force from the drive source, wherein the blades comprise a blade shaft that extends in the direction of a second axis intersecting the first axis and is connected to the driven part at one end and is rotatably connected around the second axis, and a blade support member that extends in a direction intersecting the blade shaft at the base end of the blade shaft and is rotatably connected integrally with the blade shaft, A flapping device comprising: a blade body supported by the blade shaft and the blade support member and rotating integrally with the blade shaft; a main frame that rotatably supports at least the driven part and supports the drive source; a suspension part suspended below the main frame; and a spherical shell-shaped leg part provided at the lower end of the suspension part and forming part of a sphere.

2. The flapping device according to claim 1, further comprising: a stopper that restricts the rotation of the blade shaft to a predetermined rotation angle; and a limiter that is rotatably mounted integrally with the blade support member and restricts the rotation of the blade shaft by contacting the stopper.

3. A pair of blades, and a drive unit provided corresponding to each of the pair of blades, wherein the drive unit comprises a drive source, a driven part that rotates around a first axis upon receiving power output from the drive source, a first biasing member that applies a biasing force to the driven part in the opposite direction to the rotation direction of the driven part in conjunction with the rotation of the driven part, a second biasing member that applies a biasing force to the driven part in the opposite direction to the biasing direction of the first biasing member, and a control unit that controls the output of the driving force from the drive source, wherein the blades comprise a blade shaft that extends in the direction of a second axis intersecting the first axis and is connected to the driven part at one end and is rotatably connected around the second axis, and a blade support member that extends in a direction intersecting the blade shaft at the base end of the blade shaft and is rotatably connected integrally with the blade shaft, A flapping device comprising: a blade body supported by the blade shaft and the blade support member and rotating integrally with the blade shaft; a stopper that limits the rotation of the blade shaft to a predetermined rotation angle; and a limiter that is rotatably mounted integrally with the blade support member and limits the rotation of the blade shaft by contacting the stopper.

4. The flapping device according to claim 1 or 2, characterized in that the leg portion has a gap.

5. The flapping device according to claim 1 or 2, characterized in that the leg portion has a solid portion formed in the center.

6. The flapping device according to claim 1 or 2, characterized in that the first biasing member and the second biasing member are directly or indirectly connected such that their biasing forces are in opposite directions, and the first biasing member and the second biasing member are narrowed in the opposite direction to the biasing direction by the amplitude of the stroke such that the center of the stroke related to the flapping of the blades coincides with the amplitude centers of the first biasing member and the second biasing member.

7. The flapping device according to claim 1 or 2, characterized in that one end of the first biasing member and the second biasing member is directly or indirectly connected to the main frame, and the other end is directly or indirectly connected to the driven part so as to be able to rotate integrally with the driven part.

8. The flapping device according to claim 1 or 2, wherein the base body of the blade has a fringe portion that holds the outer edge, and the base end of the fringe portion is connected to the tip end of the blade support member, and the other end is connected to the tip end of the blade shaft.

9. The flapping device according to claim 1 or 2, characterized in that it has an inertial measuring device, and the inertial measuring device is located at or near the center of gravity.

10. The flapping device according to claim 1 or 2, comprising an image acquisition unit and at least one of a distance measurement unit and an altitude measurement unit, wherein the image acquisition unit is provided on the leg portion and is positioned so as not to interfere with the leg portion during image acquisition.

Images