Experimental device for measuring force of flying wing of bionic ornithopter

Abstract

The invention belongs to the technical field of bionic ornithopter experimental equipment, and particularly relates to an experimental device for measuring the force of a bionic ornithopter flying wing, which comprises an ornithopter platform, the ornithopter platform comprises two symmetrically arranged flapping rocker arms, one end of each flapping rocker arm is connected with a driving shaft of a flapping steering engine, the flapping steering engine is mounted on a steering engine fixing plate, and the other end of each flapping rocker arm is connected with a driving shaft of the corresponding flapping steering engine. The other end of the flapping rocker arm is connected with a flying wing connecting piece through a thrust ring; a flying wing main body is mounted on the flying wing connecting piece; the steering engine fixing plate is backwards connected with two carbon fiber rods, the flying wing main body is connected with the carbon fiber rods through winding of iron wires, the carbon fiber rods are installed on the tilting connecting seat in a penetrating mode, and the tail wing connecting plate is installed at the tail ends of the carbon fiber rods and connected with the tail wing main body; the tilting connecting seat is connected with the tilting steering engine, the tilting steering engine is connected with the force measuring sensor through the force measuring connecting plate, the connecting support is arranged below the force measuring sensor, and the connecting support is fixed to the top of the support. And testing and comparison of aerodynamic performance of different flying wings are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of bionic flapping-wing aircraft experimental equipment, and in particular relates to an experimental device for measuring the force of a bionic flapping-wing aircraft wing. Background Art

[0002] In the aviation field, bionic flapping-wing aircraft, with its unique flying mode, simulates the flapping of birds' wings, showing high efficiency, high energy utilization and excellent concealment, and has broad application prospects in military, scientific research and civil fields. However, the development of flapping-wing aircraft currently faces many bottlenecks, especially the flying wing design technology.

[0003] Existing flapping-wing aircraft generally have problems such as light weight, weak load capacity, low aerodynamic efficiency, and difficulty in meeting practical application requirements. In addition, in actual flight, complex incoming flow conditions make the flight trajectory and aerodynamic characteristics of flapping-wing aircraft difficult to control and predict, which greatly hinders the optimization of flight performance. At the same time, in the key technologies of flying wing design, there is a lack of efficient research methods and platforms, making it difficult to accurately and deeply analyze the aerodynamic performance of different flying wings.

[0004] In the existing technology, there are many deficiencies in the research on flapping-wing aircraft. For example, some flight test systems perform poorly in terms of vibration isolation, which affects the accuracy of test data; some driving methods and fuselage structures cannot optimize flight performance while ensuring the difference in flapping of the flying wing; small wind tunnel experimental systems are difficult to meet the aerodynamic measurement requirements of large-sized flying wings, and the observable flapping state is relatively single; and the wing rod distribution design of some flying wings is not conducive to studying the lift-enhancing effect of flexible deformation under different working conditions. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes an experimental device for measuring the force of the flying wing of a bionic flapping-wing aircraft, so as to achieve test comparison of the aerodynamic performance of different flying wings.

[0006] The experimental device for measuring the force of a wing of a bionic flapping-wing aircraft of the present invention comprises a flapping-wing aircraft platform, wherein the flapping-wing aircraft platform comprises two symmetrically arranged flapping rockers, one end of the flapping rockers is connected to a driving shaft of a flapping servo, the flapping servo is mounted on a servo fixing plate, the other end of the flapping rockers is connected to a wing connecting piece through a thrust ring, and a wing main body is mounted on the wing connecting piece; the servo fixing plate is connected to two carbon fiber rods at the rear, the wing main body is connected to the carbon fiber rods by winding iron wires, the carbon fiber rods are installed through a tilting connecting seat, and a tail connecting plate is installed at the end of the carbon fiber rods, and the tail connecting plate is connected to the tail main body;

[0007] The tilt connection seat is connected to the tilt servo, and the tilt servo is connected to the force sensor through the force measuring connection plate. A connecting support is arranged under the force sensor, and the connecting support is fixed on the top of the bracket. A counterweight block is arranged at the bottom of the bracket to increase stability.

[0008] The wing body has a semi-elliptical configuration and includes a wing surface. Wing inner ribs are arranged on the inner side of the wing surface and wing outer ribs are arranged on the outer side. The straight side of the wing body is connected to the wing main beam. A bent iron wire is also arranged at the center of the inner side of the wing, and a transverse wing sub-beam is arranged from the bent iron wire to the wing surface.

[0009] The tail body is arranged in a quarter-circle configuration, a reinforced carbon fiber sheet is arranged at the front end of the tail body, a tail main rod connected to the tail wing surface is arranged at the center of the tail body, tail edge rods are arranged on both sides of the tail body, and a tail auxiliary rod is arranged on the transverse surface of the tail body.

[0010] The bottom of the bracket is connected to a fixed base, which includes four diagonal aluminum profiles supported on the bracket. The bottom of the diagonal aluminum profile is connected to the four corners of the grounding aluminum profile. The grounding aluminum profile forms a square with internal diagonals connected, and aluminum alloy fixings are arranged at the four corners of the grounding aluminum profile for reinforcement.

[0011] The beneficial effects of the present invention are:

[0012] Compared with the prior art, the present invention realizes the changes of different flapping frequencies and different flapping angles of the flapping-wing aircraft through flapping servo drive; through the action of the tilting servo, it satisfies the different attack angle conditions that occur during the actual flight of the flapping-wing aircraft, and measures the aerodynamic force and torque generated by the flying wing in real time; in addition, the servo rocker arm is connected to the flying wing connector to replace different flying wings, so as to realize the comparison of the aerodynamic performance of different flying wings. At the same time, a counterweight block is set at the bottom of the bracket to suppress the vibration of the device in the force measurement process of the flapping-wing aircraft to a greater extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0014] Figure 1 Schematic diagram of the overall structure of the experimental device in the embodiment;

[0015] Figure 2 Schematic diagram of the connection between the flapping-wing aircraft platform and the tilting servo in the experimental device in the embodiment.

[0016] Figure 3 Schematic diagram of the flapping-wing aircraft platform structure in the experimental device in the embodiment.

[0017] Figure 4 Schematic diagram of explosion at the tilting servo in the experimental device in the embodiment.

[0018] Figure 5 It is a partial structural schematic diagram of the experimental device in the embodiment.

[0019] Figure 6 Schematic diagram of the flying wing body and the tail wing body of the experimental device in the embodiment.

[0020] Figure 7 It is a modal diagram of the force measurement experiment of the flying wing with angle of attack in the embodiment.

[0021] Figure 8 It is a schematic diagram of the synchronous and asynchronous flapping of the wings on both sides of the flapping-wing platform in the embodiment.

[0022] In the accompanying drawings, the structural names represented by the reference numerals are:

[0023] 1- flapping rocker arm, 2- flapping servo, 3- servo fixing plate, 4- thrust ring, 5- flying wing connector, 6- tilt connector A, 7- tilt connector B, 8- carbon fiber rod, 9- tilt connector C, 10- tilt fixing A, 11- tilt servo, 12- tilt connection block, 13- tilt fixing B, 14- force measuring connecting plate, 15- force measuring sensor, 16- tail connecting plate A, 17- tail connection Plate B, 18-connecting support, 19-bracket, 20-counterweight, 21-diagonal bracing aluminum profile, 22-aluminum alloy fixings, 23-grounding aluminum profile, 24-bent wire, 25-wing inner rib, 26-wing wing surface, 27-wing outer rib, 28-wing secondary beam, 29-wing main beam, 30-reinforced carbon fiber sheet, 31-tail main rod, 32-tail edge rod, 33-tail wing surface, 34-tail secondary rod. DETAILED DESCRIPTION

[0024] The specific embodiments of the present invention are further described below. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0025] Example 1

[0026] In order to better test and compare the aerodynamic performance of different flying wings, in this embodiment, refer to Figures 1 to 6As shown, an experimental device for measuring the force of a bionic flapping-wing aircraft wing is proposed, including a flapping-wing aircraft platform, the flapping-wing aircraft platform including two symmetrically arranged flapping rockers 1, one end of the flapping rocker 1 is connected to the driving shaft of a flapping servo 2, the flapping servo 2 is mounted on a servo fixing plate 3 by screws, the other end of the flapping rocker 1 is connected to a wing connector 5 by a thrust ring 4, a wing body is mounted on the wing connector 5, the wing body has a semi-elliptical configuration, and includes a wing surface 26, a wing inner rib 25 is arranged on the inner side of the wing surface 26, and a wing outer rib 27 is arranged on the outer side, a wing main beam 29 is connected to the straight side of the wing body, a bent wire 24 is further arranged at the center of the inner side of the wing, and a transverse wing sub-beam 28 is arranged from the bent wire 24 to the wing surface 26. The installation method of the wing body is that the wing main beam 29 of the wing body is fixed by a thrust ring 4 and a threaded washer, and the wing sub-beam 28 is clamped on the bent iron wire 24 fixed on the carbon fiber rod 8, which can realize flapping as the flapping rocker 1 rotates repeatedly. Through such an installation design, the wing can be replaced quickly and conveniently.

[0027] The servo fixing plate 3 is connected to two carbon fiber rods 8 at the rear, and the flying wing body is connected to the carbon fiber rods 8 by winding with bent iron wires 24; the force measurement design of the flapping-wing aircraft force measurement experiment mainly considers the comparison of the results of the flying wing coping with different angles of attack and incoming flows, so it is necessary to add a part to realize the change of the angle of attack of the flying wing, the carbon fiber rods 8 are installed through the tilting connection seat, and the tail connecting plate is installed at the end of the carbon fiber rods 8, and the tail connecting plate is connected to the tail body. The tail connecting plate includes a tail connecting plate A16 fixed on the carbon fiber rods 8, and a tail connecting plate B17 fixed inside the tail connecting plate A16; the tail body is set to a quarter-circle configuration, and a tail body front end is set The solid carbon fiber sheet 30 is connected to the tail connecting plate B17 by screws, a tail main rod 31 connected to the tail wing surface 33 is arranged at the center of the tail body, tail edge rods 32 are arranged on both sides of the tail body, and a tail auxiliary rod 34 is arranged on the transverse surface of the tail body; specifically, the tilt connection seat is composed of a tilt connection piece A6, a tilt connection piece B7, and a tilt connection piece C9, the tilt connection seat is connected to the tilt servo 11, the top of the tilt servo 11 is connected through a tilt fixing piece A10, the side of the tilt servo 11 is connected to the tilt fixing piece B13 through a tilt connection block 12, the tilt servo 11 is connected to the force sensor 15 through a force measuring connecting plate 14, the force sensor 15 is an ATI GAMMA model, a connecting support 18 is arranged under the force sensor 15, the connecting support 18 is fixed to the top of the bracket 19, and a counterweight block 20 is arranged at the bottom of the bracket 19 to increase stability.

[0028] The bottom of the bracket 19 is connected to a fixed base. The design of the fixed base needs to ensure firmness, stability, vibration isolation, and high load-bearing capacity. In this regard, the present embodiment has a fixed base based on a triangular structure with a stable design. The angles of the two aluminum alloy profiles connected to each other are both 45 degrees, and the two are fixed by aluminum alloy connectors with screws. The aluminum profile base designed based on a triangular structure with a stable design can reduce the vibration effect of the flapping process of the flapping-wing aircraft and ensure the accuracy of the force measurement data. Specifically, the fixed base includes four diagonal bracing aluminum profiles 21 supported on the bracket 19. The bottom of the diagonal bracing aluminum profile 21 is connected to the four corners of the grounding aluminum profile 23. The grounding aluminum profile 23 constitutes a square with diagonally connected internal parts, and aluminum alloy fixings 22 are provided at the four corners of the grounding aluminum profile 23 for reinforcement.

[0029] See also Figure 7 As shown, in response to the change in angle of attack, a large torque tilting servo 11 is selected, and the specific angle of attack during the flying wing force measurement is ensured by driving the tilting servo 11 to simulate the actual flight situation. The actual force measurement condition is designed to be in the range of 0 degree angle of attack to 30 degree angle of attack. The installation angle of the flying wing is 0 degree. When the angle of attack changes, the overall windward surface of the flapping wing platform increases, which is consistent with the actual flight situation.

[0030] The specific force measurement experimental process of the experimental device is that the remote control end provides control signals to the corresponding flapping servo 2 and tilting servo 11, thereby changing the flapping frequency, flapping amplitude, angle of attack and other parameters of the flapping-wing aircraft. At the same time, the computer end controls the wind wall or wind tunnel equipment to produce certain incoming flow conditions. After the incoming flow wind speed is stable, the data of the force sensor 15 is measured in real time, focusing on the aerodynamic force and torque data, and making a comparison. The initial flapping amplitude of the flapping-wing aircraft is set to -30 degrees to +30 degrees, and the flapping frequency is between 2 Hz and 6 Hz. The synchronous and asynchronous flapping principles of the flapping-wing platform are as follows: Figure 8 As shown in the figure, the flapping modes corresponding to the flapping-wing platform include synchronous flapping, which corresponds to the change of the flapping center position and the difference in flapping amplitude. Through the direct drive of the servo, the effect of the flapping mode of the flying wing on the overall aerodynamic characteristics of the flying wing can be analyzed from multiple angles.

[0031] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all details in detail, nor do they limit the invention to only the specific embodiments described. Obviously, many modifications and changes can be made according to the content of this specification.

Claims

1. An experimental device for measuring the force of a bionic flapping-wing aircraft wing, characterized in that: The flapping-wing aircraft platform comprises two flapping rockers (1) which are symmetrically arranged, one end of the flapping rocker (1) is connected to a driving shaft of a flapping servo (2), the flapping servo (2) is mounted on a servo fixing plate (3), the other end of the flapping rocker (1) is connected to a flying wing connecting piece (5) through a thrust ring (4), and a flying wing main body is mounted on the flying wing connecting piece (5); the servo fixing plate (3) is connected to two carbon fiber rods (8) at the rear, the flying wing main body is connected to the carbon fiber rods (8) by winding iron wires, the carbon fiber rods (8) are installed through the tilting connection seat, and a tail connecting plate is installed at the end of the carbon fiber rods (8), and the tail connecting plate is connected to the tail main body; The tilting connection seat is connected to the tilting servo (11), and the tilting servo (11) is connected to the force sensor (15) through the force measuring connection plate (14). A connecting support (18) is arranged under the force sensor (15), and the connecting support (18) is fixed on the top of the bracket (19). A counterweight block (20) is arranged at the bottom of the bracket (19) to increase stability.

2. The experimental device for measuring the force of the wing of a bionic flapping-wing aircraft according to claim 1, characterized in that: The flying wing main body is semi-elliptical in configuration, and comprises a flying wing wing surface (26), wherein a flying wing inner rib (25) is arranged on the inner side of the flying wing wing surface (26), and a flying wing outer rib (27) is arranged on the outer side. A flying wing main beam (29) is connected to the straight side of the flying wing main body, a bent iron wire (24) is also arranged at the center of the inner side surface of the flying wing, and a transverse flying wing sub-beam (28) is arranged from the bent iron wire (24) to the flying wing wing surface (26).

3. The experimental device for measuring the force of the wing of a bionic flapping-wing aircraft according to claim 1, characterized in that: The tail body is arranged in a quarter-circle configuration, a reinforced carbon fiber sheet (30) is arranged at the front end of the tail body, a tail main rod (31) connected to a tail wing surface (33) is arranged at the center of the tail body, tail edge rods (32) are arranged on both sides of the tail body, and a tail auxiliary rod (34) is arranged on the transverse surface of the tail body.

4. The experimental device for measuring the force of the wing of a bionic flapping-wing aircraft according to claim 1, characterized in that: The bottom of the bracket (19) is connected to a fixed base, and the fixed base includes four diagonal bracing aluminum profiles (21) supported on the bracket (19). The bottom of the diagonal bracing aluminum profile (21) is connected to the four corners of the grounding aluminum profile (23). The grounding aluminum profile (23) forms a square with internal diagonal connections, and aluminum alloy fixings (22) are arranged at the four corners of the grounding aluminum profile (23) for reinforcement.

Images