RU2659357C2 - Ornithopter - Google Patents

Abstract

FIELD: aviation.

SUBSTANCE: invention relates to aviation, in particular to the aircraft designs with flapping wings. Ornithopter comprises a body with hinged wings and a power plant to drive said wings, which is rigidly attached to the body cylinder with piston and rod and two brace wings. Struts are hingedly connected each with their own wing and with the cylinder rod. Ring is fixed on the ornithopter body with the possibility of rotation. Vertical axis is installed in the body with the possibility of vertical-return movement, coaxially located with the rod, connected with it and carrying two wings. Lifting surfaces of the wings are opposite to each other. Two wings are mounted on a vertical axis with the ability to rotate around it and oscillate in a vertical plane and are hingedly connected by struts with a ring. Two other wings are hinged on the ring in a plane perpendicular to the plane of installation of the two wings of the vertical axis, hingedly connected by rods to the vertical axis with the possibility of rotation around it and oscillations in the vertical plane.

EFFECT: provides a reduction in dynamic loads on the body and chassis, smoothing the fluctuations of the lifting force of the ornithopter.

1 cl, 3 dwg

Description

The present invention relates to the field of aviation, in particular to the design of aircraft with flapping wings.

Known ornithopter, comprising a body with pivotally mounted wings, a power plant, consisting of a power unit and a drive of flapping movements of the wing. The latter consists of a hydraulic cylinder rigidly attached to the body with a piston and a rod and two rods. Some ends of the rods are pivotally connected to the rod of the hydraulic cylinder, and the other ends are pivotally connected each to the base of the corresponding wing. RU 2270136, B64C 33/00, 02.20.2006.

The disadvantage of this technical solution is the lack of flapping wings of the ornithopter, allowing for vertical launch. The appearance of a lifting force on the wings of an ornithopter is possible only when they are blown by a counter flow of air. To create the necessary lifting force for takeoff, the ornithopter needs a relatively long take-off runway for acceleration. Take-off of an ornithopter with a limited size platform is not possible.

Muscles are known that use the principle of action of a device for testing flapping wings, proposed by P.F. Shalimov. The device contains a vertical axis, with two wings pivotally mounted on it, the planes of which are located opposite to each other, and a sleeve movably mounted on the vertical axis, pivotally connected to the wings by struts. The wings are mounted on an axis with the possibility of rotation around it and oscillations in the vertical plane. In the case of vertical-return movement of the sleeve along the vertical axis, it acts through the struts on the wings and the wings wave. Traction forces arise on them, oppositely directed, due to the opposite direction of the planes of the wings. Under the influence of these forces, the wings, waving, accelerate in a circle, according to the speed of rotation of the wings they judge the thrust they develop (Vasiliev G.S. Fundamentals of the flight of models with flapping wings. - M .: Oborongiz, 1953, p. 104). But on the wings there are also lifting forces due to the flow around them with a counter flow of air. This was used in vertical launch muscle systems.

Muscles with a vertical start contain a vertical axis, two wings mounted on a vertical axis with the possibility of rotation around it and vibrations in the vertical plane, and a sleeve movably mounted on a vertical axis and articulated by struts with wings. The planes of the wings are located opposite to each other. The lifting forces arising on the wings raise the wings and the vertical axis with the platform for the pilot. The pilot moves the sleeve with his hands (Vladimir Toporov. Mechanics of the living sky. Mahokryly - rotopters -http: //vitanar.narod.ru/autors/toropovvlad/toropovvlad.htm).

The disadvantage of this technical solution is the absence of the wings of the muscular system, creating horizontal traction. Horizontal flight of a muscular vehicle is not possible.

A known design of the device with flapping wings with a vertical start, including a platform (body), a vertical shaft mounted in the platform with the possibility of vertical-return movement, two wings with oppositely directed bearing planes, a rolling bearing rigidly mounted on the platform. The wings are mounted on a vertical shaft with the possibility of rotation around its axis and oscillations in the vertical plane and levers (struts) are pivotally connected to the outer ring of the rolling bearing (Shcherbatykh AG Musculolettes. Chelyabinsk: “Kray Ra”, 2013, p. 124).

The disadvantage of this design is the lack of wings in the apparatus, creating horizontal traction. Horizontal flight is not possible.

Closest to the claimed technical solution (prototype) is a flywheel containing a body with pivotally mounted wings and a power unit for driving the wings, including a cylinder rigidly attached to the body with a piston and a rod and two wing struts. The struts are pivotally connected each to its wing and to the cylinder rod. A sleeve is fixed in the housing for rotation, inside of which a vertical axis is placed with a gap allowing their relative sliding and rotation. The axis is coaxially located with the stem, connected with it and carries two wings, the planes of which are located opposite to each other. Two wings are mounted on the vertical axis with the possibility of rotation around it and vibrations in the vertical plane and are articulated by struts with the sleeve. RU 2578389, B64C 33/02, 27.03. 2016.

The disadvantage of this technical solution is the presence of unbalanced oscillating masses - flapping wings, as well as the fluctuation of the aerodynamic forces - lifting and traction. These forces are formed on the flapping wing, mainly for half the period of a complete flap of the wing: on the flap of the wing down (Tikhonravov M.K. Flight of birds and cars with flapping wings. - 2nd ed., Ext. - M .: Oborongiz, 1949, p. 68). The presence of unbalanced masses can cause vibrational phenomena and the appearance of stresses that go beyond the permissible levels in the links of the drive mechanism, housing, chassis and reduce the reliability and durability of the mahogany. Fluctuations in the magnitudes of the lifting forces on the flapping and simultaneously rotating (rotating) wings can also cause vibration, and in flight can lead to vertical vibrations of the flight unit along with the cockpit, which will worsen comfortable flight conditions.

The task to which the claimed invention is directed is to create a mahogany, in which the negative effects of unbalanced oscillating masses and fluctuations in the values of aerodynamic forces on the rotating wings are significantly reduced.

This problem is solved due to the fact that in the inventive rotocryal mahogany containing a body with pivotally mounted wings, a power unit including a cylinder rigidly attached to the body with a piston, the rod of which is articulated by struts with wings, a ring, vertical mounted on the body with the possibility of rotation an axis mounted in the housing with the possibility of vertical-return movement, coaxially located with the stem and connected with it and carrying two wings, the bearing surfaces of which are located opposite to according to the invention, two wings can be pivotally mounted in a plane perpendicular to the plane of installation of two wings of the vertical axis, pivotally connected with rods to each other, mounted on a vertical axis with the possibility of rotation around it and vibrations in the vertical plane and articulated by struts with the ring vertical axis with the possibility of rotation around it and vibrations in a vertical plane, the bearing surfaces of which are located opposite to each other and oriented nalogichno with bearing surfaces of the vertical axis of the wings.

The technical result provided by the given set of features is the possibility of balancing the oscillating masses of the flapping and simultaneously rotating (rotating) wings and reducing the amplitude of the fluctuation of the aerodynamic forces on the flapping rotating wings.

In FIG. 1 shows a schematic of the rotocryal mahogany.

Makholet-winged wing contains a housing 1 with pivotally mounted wings 2, a power unit 3, a cylinder 4, a rod 5 of which is pivotally connected by struts 6 to the wings 2. The cylinder 4 is rigidly attached to the housing 1. On the housing 1 is rotatably fixed ring 7. Inside the housing 1, a vertical axis 8 is mounted with the possibility of vertically-reverse motion relative to the housing. The vertical axis 8 is installed coaxially with the stem 5, is connected and carries two wings 9, the bearing surfaces of which are located opposite to each other. The wings 9 are pivotally connected by struts 10 to the ring 7, and their bases are pivotally connected to the yoke 11, which is mounted on a vertical axis with the possibility of rotation. Thus, the wings 9 are mounted on a vertical axis with the possibility of rotation around it and vibrations in the vertical plane. Two wings 12 are pivotally mounted on ring 7 in a plane perpendicular to the plane of installation of two wings 9, that is, in a plane perpendicular to the plane of the drawing. In FIG. 2 shows the installation diagram of the wings 12 (for clarity, the wings 12 are shown in the diagram of Fig. 1 in the dashed plane of the drawing). The wings 12 are pivotally connected by rods 13 to the yoke 11 of the vertical axis 8 (the rods 13 are also indicated by a dotted line, since they are also located in a plane perpendicular to the plane of the drawing). Thus, the wings 12 are mounted to rotate around a vertical axis 8 and oscillate in a vertical plane. The bearing surfaces of the wings 12 are located opposite to each other and are oriented similarly to the bearing surfaces of the wings 9. That is, if the installation planes of the wings 9 and 12 (as shown in the diagram of Fig. 1) are combined, then the horizontal projections of the bearing surfaces of the latter coincide. Makholet-rotokryl has a chassis 14, which is equipped with shock absorbers to soften the landing. Windows 15 are provided in the housing 1 for unobstructed movement of the struts 6. To compensate for possible distortions in the guides of the housing, the vertical axis 8 is connected to the rod 5 by means of a hinge. Wings 2, 9, 12 are made with an elastic trailing edge, which contributes to the automatic installation of the bearing surfaces of the wings at a more optimal angle of attack during their flapping movements (Tikhonravov M.K. Flight of birds and cars with flapping wings. - 2nd ed., Ext. . - M .: Oborongiz, 1949, p. 149).

Makholet-rotokryl works as follows.

With a working power plant 3 - it can be an internal combustion engine with a hydraulic pump or compressor or a steam generator (steam boiler) - the working fluid (oil, compressed air, steam) enters the cylinder 4. The rod 5 causes the vertical axis 8 to rotate vertically, which through the clip 11 moves up and down the base of the wings 9 and pulls and pushes the thrust 13 of the wings 12. The wings 9 and 12 come in flapping motion. Traction forces occur on flapping wings. In view of the fact that the bearing surfaces of the wings 9 and 12 are located opposite to each other, the thrust forces on them are directed opposite and form pairs of forces, under the influence of which the wings 9 and 12 with struts 10, rods 13 and ring 7 rotate around the vertical axis 8. Under the influence of the oncoming air flow on the wings 9 and 12, lifting forces arise, which raise the rotocryo under the struts 10 and the ring 7 and through the rods 13 and the yoke 11. Horizontal flight is carried out due to the thrust of the wings 2, driven by flapping through the struts 6 from the rod 5. It is important that the bearing surfaces of the wings 12 are oriented similarly to the bearing surfaces of the wings 9 to create a pair of forces in the same direction of rotation as the wings 9. Otherwise, with the opposite orientation of the bearing surfaces of the wings 12 and 9, pairs of forces of the opposite direction will form on them, the rotation of the wings will stall and the vertical launch of the rotorcraft will not be possible.

Oscillating (flapping) wings are a source of periodically varying dynamic inertial forces, perceived by the body of the mahogany through kinematic pairs (bearings) and transmitted to the chassis. Dynamic pressures transmitted to the hull and chassis can cause vibration phenomena in the mechanisms and parts of the fringe. These vibrational phenomena increase stress in the material of the details of the detail. Possible proximity to the resonance zone, which can cause the appearance of stresses that go beyond the permissible values. It has been established that the destruction of parts at alternating voltages occurs at significantly lower values than under static loading. Under cyclic loads with a sufficiently large number of cycles, irreversible changes accumulate in the metal of the parts - fatigue, microscopic cracks form in the most stressed place of the part, the gradual development of which leads to failure - fatigue failure. Therefore, the problem of fatigue resistance is the key to improving the reliability of machines (Orlov PI, Fundamentals of Design. Book 1. - Ed. 3rd, rev. - M.: Mechanical Engineering, 1988, p. 194).

One of the main ways to increase the fatigue strength of parts is to reduce dynamic loads - to do this, balance or balance the mechanism. Balancing is carried out using counterweights (Handbook of the mechanics of an engineering plant. In 2 volumes, Volume 1. / Under the editorship of R.A. Noskin. - M .: Engineering, 1971, p. 27). In the inventive rotocryal wingstop, the wings 9 serve as a counterweight to the wings 12. When the vertical axis 8 goes up, it forces the wings 9 to swing down, and wings 12 through the thrust 13 - swing up, and vice versa. That is, the rotating wings 9 and 12 alternately converge and diverge. The dynamic inertial forces excited by them will also be multidirectional. It is important that in the manufacture of the rotating wings 9 and 12 their geometrical dimensions and weights are kept the same, that the struts 10 and the thrusts 13 are the same, and that the fastenings of the latter to the yoke 11 and ring 7 are at the same radii from the vertical axis 8, as well as at the same the radii were the attachment points of the struts 10 to the wings 9 and the rods 13 to the wings 12. Then, ideally, there will be complete static and dynamic balancing of the flapping and simultaneously rotating (rotating) wings 9 and 12, which will significantly reduce the dynamic inertial loads and the links of the wing drive to the hull and landing gear of the rotorcraft and, ultimately, will increase its reliability and durability. It should be said that we are talking about complete mechanical balancing of the wings 9 and 12, there will be no complete aerodynamic balancing of the wings 9 and 12, since the aerodynamic forces on the flapping wing with its swing up and down are generally different. Therefore, there will be fluctuations in the resulting aerodynamic force in the rotocryo.

Let us evaluate the effect of the introduction of a pair of wings 12 on the oscillation of the resulting lifting force from the rotating wings of the rotocryal mahogany.

In FIG. 3 shows a graph of the bearing (lifting) and pulling (thrust) forces for the flapping wing of a gull, taken from the above work: Tikhonravov M.K. “Flight of birds and cars with flapping wings. 1949 ", p. 68. We will use it for our estimation, proceeding from the fact that the gull is a natural maholet. In the graph of FIG. 3 curves 1 and 2 for the lifting and traction forces, respectively, developed by the flapping wing of the gull, were obtained by MK Tikhonravov, as well as the upper dashed curve indicating the trajectory of the wing of the gull with the silhouette of a bird. Curves 3 and 4 are plotted by us on this graph and obtained from the following considerations. We assume in a first approximation that curve 1 qualitatively shows the change in lift on wings 9 for a full swing; since wings 12 are ahead in wingspan half a period of wings 9, then shifting curve 1 by half a period (the part of curve 1 corresponding to the section “Max up” will be transferred to the section “Max down”), we will obtain curve 3 (dashed line) - change in lifting force by wings 12 for a complete flap. The graphical addition of curves 1 and 3 gives curve 4 — the change in the resulting lifting force of the rotorcraft from the total effect of wings 9 and 12 for their complete swing.

We see that curve 4 for the resulting lifting force is smoother compared to curves 1 and 3 for the partial lifting forces of the wings 9 and 12, respectively: the oscillation frequency on curve 4 increased (the number of half waves increased) and their amplitude decreased compared to curves 1 or 3. Compare these amplitudes. To do this, we divide the segments depicting their values on curves 1 and 4, the segments are measured in millimeters:

a / b = 13/7 = 1.86,

A / B = 19 / 10.5 = 1.82,

where a is the largest amplitude of the fluctuation of the lifting force on the wings 9 or 12;

b is the largest amplitude of the oscillations of the resulting lifting force from the total action of the wings 9 and 12;

A - the largest range of changes in the lifting force of the wings 9 or 12 for their full swing;

In - the largest range of changes in the resulting lifting force for a complete flap of the wings 9 and 12.

Thus, the use of two pairs of rotating wings 9 and 12 leads to a decrease in the amplitude of the oscillation of their total lifting force by not less than 80% compared with the magnitude of the lifting force of one pair of rotating wings 9. And, therefore, in horizontal flight, oscillations of the wing-and-wing wing together with the cockpit will feel much weaker.

That is, the task of constructing a roto-wing mahogany with reduced vibrational phenomena due to fluctuations in the moving masses of the wings and fluctuations in the aerodynamic forces on the wings is solved.

Claims (1)

Makholet, comprising a body with hinged wings, a power unit including a cylinder rigidly attached to the body with a piston, the rod of which is pivotally connected to the struts with wings, a ring mounted on the body with the possibility of rotation, a vertical axis mounted coaxially with the possibility of vertical-return movement with a stem and associated with it and carrying two wings, the bearing surfaces of which are located opposite to each other, mounted on a vertical axis with the possibility of rotation in its circumference and vibrations in the vertical plane and articulated with the ring, characterized in that two wings are articulated on the ring in a plane perpendicular to the plane of installation of two wings of the vertical axis, articulated by rods with a vertical axis with the possibility of rotation around it and vibrations in the vertical plane , the bearing surfaces of which are located opposite to each other and oriented similarly to the bearing surfaces of the wings of the vertical axis.

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