CN107416202B

CN107416202B - Miniature flapping wing aircraft

Info

Publication number: CN107416202B
Application number: CN201710541697.7A
Authority: CN
Inventors: 邓慧超; 周文娟
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2017-07-05
Filing date: 2017-07-05
Publication date: 2020-11-10
Anticipated expiration: 2037-07-05
Also published as: CN107416202A

Abstract

The invention discloses a micro flapping wing air vehicle, and belongs to the field of bionic flying robot equipment. The flapping wing mechanism comprises a connecting rod and a wing frame, the connecting rod is connected to a gear of the speed reducing mechanism through a pin, and the two wing frames are connected with the center of the rack and are respectively arranged on two sides. The passive rotating mechanism comprises a rotating block and a stop lever, the stop lever is positioned on the wing frame, and the rotating block rotates along with the wing shaft. The wing is connected to the wing frame through the passive rotating mechanism, and the wing shaft penetrates through the wing frame hole and is connected with the rotating block. The gears of the speed reducing mechanism are respectively connected to the corresponding positions of the rack, and the micro motor drives the pinion to form a secondary speed reducing mechanism. The wing flapping and passive rotation device has the advantages of small volume, light weight and low energy consumption, can realize flapping and passive rotation of the wings at the same time, and is more favorable for flight of an aircraft.

Description

Miniature flapping wing aircraft

Technical Field

The invention relates to an insect-imitated microminiature flapping wing aircraft, and belongs to the field of bionic flying robot equipment.

Background

In nature, flying birds and insects is carried out by flapping wings. The flying mode of flapping the flapping wings up and down can provide larger thrust, improve the flying efficiency and realize more flexible flying action of the small aircraft. In recent years, with the rapid development of technologies such as aerodynamics and MENS, a micro aircraft has been developed into a new aircraft which is widely concerned at home and abroad. The novel flying vehicle has the advantages of small volume, portability, flexible flight, good concealment and the like, so the novel flying vehicle has very wide application prospect in the fields of civil use and national defense. Compared with fixed wing aircrafts and rotary wing aircrafts, the flapping wing aircraft has the advantages of no need of propellers or air injection devices, capability of rapidly taking off, accelerating, hovering and the like in situ or in small fields, and occupies an increasingly important position in the research field.

In military terms, the micro aircraft is mainly used for tasks such as low-altitude reconnaissance, communication, electric interference and ground attack. The miniature aircraft can be used for detail reconnaissance at the front edge of cities, mountain forests and battlefields, reconnaissance images and information are transmitted to a monitor in a fighter hand, battlefield information is provided for a command department in time, and the combat efficiency can be greatly improved.

In the civil field, the micro aircraft can be used for communication relay, environmental research, and monitoring and support of natural disasters. The micro aircraft can also be used for border patrol and control, drug contraband and agricultural survey, and has wide market and application prospect in future large-scale pastures and urban area monitoring and the like.

The current research situation of domestic and foreign micro flapping wing air vehicles:

at present, many research institutions at home and abroad have fully developed the design research on the micro flapping wing air vehicle. The American Georgia technical research institute and the Cambridge university in England jointly develop a miniature flapping wing aircraft (Entomopter) by utilizing reciprocating chemical muscles, wherein the flapping wing aircraft has two pairs of wings similar to butterfly wings, has a compact structure and higher energy conversion efficiency. The university of California in the United states adopts a PZT piezoelectric actuator and a double-rocker four-bar linkage mechanism to independently develop mechanical fly 'MFI', and can realize large-amplitude flapping wing vibration similar to insects, wherein the vibration frequency is as high as 150 HZ. The California research institute and aviation environmental company jointly develops the first palm-sized electric flapping-wing machine 'micro bat MicroBat' in the world by driving a single-crank double-rocker mechanism by a micromotor, the body framework and the wings of the electric flapping-wing machine are made of novel super-strong composite materials, and the wings are processed and manufactured by adopting an MEMS technology. The miniature flapping wing air vehicle designed by the Harbin industry university utilizes the elliptical cylindrical cam driving mechanism and the wing torsion whole machine mechanism to reduce the negative lift effect in the flapping process of the wing, thereby improving the flight capability. The total target mass of the flapping wing air vehicle designed at present is dozens to hundreds of grams, and the lithium battery serving as a main energy source cannot provide enough energy for the flight of the flapping wing air vehicle, so that the flapping wing air vehicle needs to be miniaturized and lightened.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a novel multi-degree-of-freedom miniature flapping wing aircraft which is small in size, light in weight and low in energy consumption and can realize wing flapping and rotation at the same time.

A micro flapping wing aircraft comprises a rack, a connecting rod, a wing frame, a rotating block, wings, a first gear, a second gear, a third gear, a fourth gear and a motor;

the motor is positioned in the center of the rack, the third gear and the fourth gear are coaxially arranged, the first gear, the second gear and the fourth gear are positioned on the rack, and the two wing frames are connected with the rack and positioned on two sides of the rack respectively;

the first gear, the second gear, the third gear and the fourth gear form a speed reducing mechanism, the third gear is connected with a motor shaft of a motor, the motor drives the third gear to rotate, the third gear drives the fourth gear to rotate for primary speed reduction, and the fourth gear respectively drives the first gear and the second gear to rotate for secondary speed reduction;

the flapping wing mechanism is a double-crank rocker mechanism, one end of one connecting rod is connected with the first gear, the other end of the connecting rod is connected with the wing frame to form a crank of the crank rocker mechanism, one end of the other connecting rod is connected with the second gear, and the other end of the other connecting rod is connected with the wing frame to form a rocker of the crank rocker mechanism;

the wing comprises a wing vein and a wing membrane, the wing membrane is fixed on the wing vein, a wing shaft is arranged on the wing vein, the wing shaft penetrates through the wing frame to be connected with a rotating block, and the rotating block rotates along with the wing shaft;

the stop lever, the rotating block and the wing shaft of the wing form a passive rotating mechanism, the rotating block is provided with a lug, and when the wing rotates to a specific angle, the stop lever blocks the rotating block.

The invention has the beneficial effects that:

compared with the prior art, the flapping wing device adopts the double-crank double-rocker mechanism as the flapping wing mechanism, the structure is simple and easy to realize, the phase difference of the two wings is avoided, the control is convenient, and the stability is high. The invention also designs a passive rotating mechanism, which can realize the rotation of the wings in the flying process and is more beneficial to the self-adaptive flight of the flapping wing air vehicle. The whole mechanism of the flapping wing aircraft selects the minimum modulus of the gear which can be achieved, the structure is simple and compact enough, the size of the whole structure is very small, the weight is less than 10g, the purposes of miniaturization and light weight are achieved, and the flight of the flapping wing aircraft is more flexible.

Drawings

FIG. 1 is a perspective view of the overall structure of the present invention;

FIG. 2 is a view of the airfoil of the present invention;

FIG. 3 is a diagram of the passive rotary mechanism of the present invention;

FIG. 4 is a view showing the mechanism of the reduction mechanism according to the present invention;

FIG. 5 is a block diagram of the flapping wing mechanism of the present invention;

FIG. 6 is an overall block diagram of the housing of the present invention;

FIG. 7 is a basic structural view of a first gear;

FIG. 8 is a block diagram of a wing frame;

in the figure:

1-frame 2-connecting rod 3-wing frame

4-rotating block 5-wing 6-pin

7-first gear 8-second gear 9-third gear

10-fourth gear 11-motor 12-stop lever

1.1-wing frame hole 1.2-motor hole 1.3 first gear connecting hole

1.4-second gear connection hole 1.5-fourth gear connection hole

3.1-connecting hole 3.2-rocker positioning hole 3.3-wing hole

5.1-vein branch 5.2-wing shaft

7.1-fixed hole 7.2-crank positioning hole

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

The invention discloses a micro flapping wing air vehicle, which comprises a frame 1, a connecting rod 2, a wing frame 3, a rotating block 4, a wing 5, a first gear 7, a second gear 8, a third gear 9, a fourth gear 10 and a motor 11, wherein the connecting rod 2 is connected with the frame;

as shown in fig. 1 and 4, a motor 11 is arranged in the center of the frame 1, the motor 11 can be a micro-miniature hollow cup motor, the motor 11 is driven by a lithium battery or an external power supply, and the power of the micro flapping wing aircraft comes from the motor 11;

as shown in fig. 4, the reduction mechanism of the present invention includes a first gear 7, a second gear 8, a third gear 9, and a fourth gear 10. The third gear 9 is connected with a motor shaft of a motor 11, and the third gear and the motor shaft are in interference fit; the motor 11 drives the third gear 9 to rotate, and the third gear 9 in turn drives the fourth gear 10 to rotate and perform primary speed reduction. The fourth gear 10 drives the first gear 7 and the second gear 8 to rotate respectively, and completes the two-stage speed reduction of the motor 11.

As shown in fig. 5, the flapping wing mechanism of the present invention comprises a first gear 7, a second gear 8, connecting rods 2 and a wing frame 3, the flapping wing mechanism adopts a double crank rocker mechanism, one end of one connecting rod 2 is fixed in a crank positioning hole 7.2 on the first gear 7 through a pin 6, as shown in fig. 7, a crank of the crank rocker mechanism is formed, the pin 6 is in clearance fit with the positioning hole 7.2, and the pin 6 is also in clearance fit with the connecting rod hole; the other end of the connecting rod 2 is connected with a rocker positioning hole 3.2 of the wing frame 3 through a pin 6, as shown in fig. 8, a rocker of the crank rocker mechanism is formed, and the pin 6 is in clearance fit with the connecting rod 2 and the rocker positioning hole 3.2. The rotation angle range of the rocker is determined through the design of the positions and the sizes of the crank positioning hole 7.2, the connecting rod 2 and the rocker positioning hole 3.2, so that the range of the flapping angle of the wing 5 is determined.

As shown in fig. 6, the frame 1 is provided with a wing frame hole 1.1, a motor hole 1.2, a first gear connection hole 1.3, a second gear connection hole 1.4, and a fourth gear connection hole 1.5, respectively. There are strict dimensional requirements between the holes in the frame 1 so that the parts attached to the frame 1 can fit closely. The wing frame holes 1.1 are respectively connected with the connecting holes 3.1 of the two wing frames 3 through pins 6, and the pins 6 are in interference fit with the wing frame holes 1.1; the motor hole 1.2 is used for fixing the motor 11, and the motor hole 1.2 is in interference fit with the motor 11; the first gear connecting hole 1.3 is connected with a fixing hole 7.1 of the first gear through a pin 6, and the pin 6 is in interference fit with the first gear 7 connecting hole 1.3; the second gear connecting hole 1.4 is connected with a fixing hole 7.1 of the second gear 8 through a pin 6, and the pin 6 is in interference fit with the first gear connecting hole 1.4; the fourth gear connecting hole 1.5 is connected with a fixing hole 7.1 of the fourth gear 10 through a pin 6, and the pin 6 is in interference fit with the first gear connecting hole 1.5.

As shown in fig. 3, the passive rotating mechanism of the present invention includes a stop lever 12, a rotating block 4 and a wing shaft 5.2. As shown in fig. 8, the stop lever 12 is located at a certain position near the wing hole 3.3 of the wing frame 3, and the stop lever 12 is used for stopping the wing 5 from continuing to rotate when the wing 5 rotates to a certain position, so as to prevent the wing 5 from turning over too much and losing lift force. As shown in fig. 2 and 3, the wing shaft 5.2 is in clearance fit with the wing hole 3.3, and the wing shaft 5.2 can freely rotate in the wing hole 3.3. And the wing shaft 5.2 and the rotating block 4 are in interference fit, and the rotating block 4 rotates along with the wing 5. Two lugs with fixed angles are set on two sides of the rotating block 4, and when the wing 5 rotates to a certain position, the lug can be clamped by the stop lever 12. The angular setting of the rotary block 4 defines the range of variation of the angle of attack of the wing 5 during rotation of the wing 5. In the initial position, the wings 5 flap at a certain attack angle, in the flying process, the wings 5 can convert the attack angle according to the change of wind power to adapt to the flying state, when the wind power is converted to a certain angle, the rotating block 4 is blocked by the stop lever 12 on the wing frame, the attack angle of the wings 5 cannot be increased continuously, and the mechanism controls the passive rotation of the wings 5.

As shown in fig. 1, the wing 5 includes a wing vein and a wing membrane, and the wing membrane is made of polyimide membrane and fixed on the wing vein. As shown in figure 2, the wing pulse part of the wing 5 of the invention selects the wings of the rhinoceros scarab as bionic objects, imitates the shapes of the wings, and obtains the whole appearance curve of the required wing by collecting data points at the edges of the wings and fitting the curves. This wing arteries and veins uses carbon fiber 3D printer to carry out integration printing, is equipped with branch arteries and veins 5.1 and wing axle 5.2, and wing axle 5.2 is fixed size, and wing axle 5.2 carries out clearance fit with the wing hole 3.3 of wing frame 3, carries out interference fit between the hole with rotatory piece 4.

Example (b):

as shown in fig. 1, a micro flapping wing aircraft comprises a wing 5 part for flying, a flapping wing mechanism, a speed reducing mechanism and a passive rotating mechanism. Wherein the power of the micro flapping wing air vehicle is derived from a micro hollow cup motor 11 fixed at the center of the frame 1, and the motor 11 is driven by a lithium battery or an external power supply.

As shown in fig. 2, the present invention is directed to the airfoil portion of the airfoil 5. The wing pulse selects the wings of the rhinoceros as bionic objects, the wings are simulated in shape, and the whole appearance curve of the required wings is obtained by collecting data points at the edges of the wings and performing curve fitting. The wing veins are printed by a carbon fiber printer, and a wing shaft 5.2 with fixed size is designed and connected with a wing frame 3.

As shown in fig. 3, the passive rotating mechanism of the present invention. The passive rotation mechanism comprises a stop lever 12, a rotation block 4 and a wing shaft 5.2. The function of the stop lever 12 is to stop the wing 5 from continuing to rotate when the wing 5 rotates to a certain position, so as to prevent the wing 5 from turning over too much to lose lift force and falling off. Wherein, clearance fit is adopted between the wing shaft 5.2 and the wing hole 3.3, and the wing shaft 5.2 can freely rotate in the wing hole 3.3. And the wing shaft 5.2 and the rotating block 4 are in interference fit, and the rotating block 4 rotates along with the wing 5. Two fixed-angle bumps are set on both sides of the rotating block 4, and when the wing 5 rotates to a certain position, the wing is clamped by the stop lever 12. The angular setting of the rotary block 4 defines the range of variation of the angle of attack of the wing 5 during rotation of the wing 5. In the initial position, the wings 5 flap at a certain attack angle, in the flying process, the wings 5 can convert the attack angle according to the change of wind power to adapt to the flying state, when the wind power is converted to a certain angle, the rotating block 4 is blocked by the stop lever 12 on the wing frame 3, the attack angle of the wings 5 cannot be continuously increased, and the mechanism controls the passive rotation of the wings 5.

The speed reducing mechanism according to the present invention is shown in fig. 4. The speed reducing mechanism comprises a first gear 7 (driving wheel), a second gear 8 (driving wheel), a third gear 9 (left speed reducing gear) and a fourth gear 10 (right speed reducing gear), wherein the driving wheel is connected with a coreless motor 11, the motor drives the driving wheel to rotate, and the driving wheel then drives the driving wheel to rotate and carry out primary speed reduction. The driving wheel drives the left reduction gear and the right reduction gear to rotate respectively, and secondary speed reduction of the motor is completed.

The flapping wing mechanism of the present invention is shown in FIG. 5. The flapping wing mechanism comprises a left reduction gear, a right reduction gear, a connecting rod 2 and a wing frame 3. One end of the connecting rod 2 is fixed on the reduction gear through a pin 6 to form a crank of the crank rocker mechanism; the other end is fixedly connected to the wing frame 3 through a pin 6 to form a rocker of the crank rocker mechanism. The rotating angle range of the rocker is determined through the size selection of the crank, the connecting rod and the rocker, so that the range of the flapping angle of the wing is determined.

Claims

1. A micro flapping wing aircraft comprises a rack, a connecting rod, a wing frame, a rotating block, wings, a first gear, a second gear, a third gear, a fourth gear and a motor;

the wings comprise wing veins and wing membranes, the wing membranes are fixed on the wing veins, the wing veins select the wings of the rhinoceros scarab as bionic objects, the wings are simulated in shape, and the whole appearance curve of the required wings is obtained by collecting data points at the edges of the wings and performing curve fitting; the wing vein is provided with a wing shaft;

the stop lever, the rotating block and the wing shaft of the wing form a passive rotating mechanism, the stop lever is positioned near the wing hole of the wing frame, the wing shaft is in clearance fit with the wing hole, and the wing shaft freely rotates in the wing hole; the wing shaft and the rotating block are in interference fit, and the rotating block rotates along with the wing; two lugs with fixed angles are arranged on two sides of the rotating block, and when the wing rotates in place, the wing can be clamped by the stop lever; the angle setting of the rotating block specifies the variation range of the attack angle of the wing in the rotating process; when the wind power is converted to a certain angle, the rotating block is blocked by a stop lever on a wing frame, the wing attack angle cannot be continuously increased, and the mechanism controls the passive rotation of the wing;

in the flapping wing mechanism, a crank positioning hole is formed in the first gear, a rocker positioning hole is formed in the second gear, and the rotation angle range of the rocker is determined by setting the length of the connecting rod and the positions of the crank positioning hole and the rocker positioning hole, so that the range of the flapping angle of the wing is determined.

2. The micro ornithopter of claim 1, wherein the wing membrane of the wing is a polyimide membrane.

3. The micro ornithopter of claim 1, wherein the wing veins are formed by 3D integrated printing of carbon fiber.