A single rotor vertical take-off and landing fixed wing aircraft power layout

Abstract

The application belongs to the technical field of overall design of vertical take-off and landing aircraft, and particularly relates to a single-blade rotor type vertical take-off and landing fixed-wing aircraft power layout structure. The main body of the power layout structure is a rotor with only one blade, one side of the rotor rotating shaft is a load cabin for loading and counterweight, and the other side is a fixed pitch rotor blade, and the rotor blade can swing; the rotor blade is provided with a driving propeller for driving the rotor to rotate or generating a level flight thrust. The single-blade rotor is a main component for generating lift in vertical take-off (rotor mode) and cruising flight (fixed-wing mode). The single-blade rotor system provided by the application can be used as a power system of a vertical take-off and landing aircraft, the power layout can consider cruising level flight efficiency and vertical take-off and landing hovering efficiency, and static balance and dynamic balance can be realized in a steady state hovering state.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of overall design of vertical take-off and landing aircraft, and particularly relates to a single-blade rotor type vertical take-off and landing fixed-wing aircraft power layout structure. BACKGROUND

[0002] The vertical take-off and landing fixed-wing aircraft is a kind of aircraft that can balance the cruising flight efficiency and certain hovering capability, and has a wide range of application scenarios in urban limited sites and complex terrain environments. In recent years, the vertical take-off and landing fixed-wing unmanned aerial vehicle has developed rapidly, which proves the wide demand for such aircraft. However, the development of the vertical take-off and landing fixed-wing aircraft still faces the design contradiction of the power device, so the heavy and manned vertical take-off and landing fixed-wing aircraft has not been applied in engineering.

[0003] The power device (here mainly referring to the propeller and rotor) of the vertical take-off and landing aircraft often faces the design contradiction between the vertical take-off and landing stage and the cruising stage, mainly embodied in the requirements of low pitch, small twist and large disc in the vertical take-off and landing stage, and the requirements of high pitch, large twist and small disc in the cruising stage. The propeller (or rotor) lift in the vertical take-off and landing stage directly overcomes the gravity, so the disc load is high, and a large disc area is needed to reduce the disc load; at the same time, the disc inflow velocity is low, so the blade twist and pitch need to be small. The propeller thrust in the cruising stage only overcomes the drag in the cruising stage, so the disc load is low, and the disc area needs to be reduced to obtain a suitable disc load; at the same time, the disc inflow velocity is high, so the blade twist and pitch need to be large. If the design contradiction of the power device cannot be well solved, the vertical take-off and landing fixed-wing aircraft is difficult to obtain higher load capacity and longer endurance.

[0004] In order to solve the above design contradiction, there are two types of technical approaches: one is to perform multi-point and multi-target optimization design on the propeller, and this type of way generally requires the propeller to have variable pitch capability, such as the tilt propeller / rotor vertical take-off and landing aircraft; the other is to separate the vertical take-off and landing and cruising flight design points from the perspective of power layout, for example, the multi-rotor-fixed-wing composite vertical take-off and landing aircraft. The power layout design separates the vertical take-off and landing and cruising design points, which can fundamentally solve the design contradiction of the power device. However, the current power layout design usually sets the propeller dedicated for vertical take-off and landing and cruising flight, or uses the rotor in the vertical take-off and landing stage and the propeller in the cruising flight, which on the one hand increases the weight in the vertical take-off and landing stage, and on the other hand increases the cruising flight resistance and dead weight. The single-blade propeller four-rotor aircraft mentioned in the prior art CN107891974A is a kind of aircraft using single-blade rotors, but it does not solve the dynamic imbalance design problem of the asymmetric rotors, which affects its engineering implementation; at the same time, it also does not solve the problem that the propulsion power becomes dead weight during hovering.

[0005] In order to obtain a power device which can better balance the vertical take-off efficiency and the cruising flight efficiency, a power layout structure which can efficiently utilize the vertical take-off and cruising flight advantages is needed to improve the vertical take-off and cruising flight efficiency while avoiding additional dead weight. SUMMARY

[0006] (1) Technical problem to be solved

[0007] The technical problem to be solved by the present application is: in view of the current demand for high-efficiency compatible power layout design of vertical take-off fixed-wing aircraft in hovering and cruising stages, how to provide a single-blade rotor type vertical take-off fixed-wing aircraft power layout, which requires that the power layout structure can eliminate the contradiction between hovering and cruising power design points, improve hovering efficiency and cruising propulsion efficiency, reduce dead weight, and eliminate dynamic and static unbalanced forces and moments of the single-blade rotor, so that the single-blade rotor can work in a form close to axisymmetric rotor.

[0008] (2) Technical solution

[0009] In order to solve the above technical problem, the present application provides a single-blade rotor type vertical take-off fixed-wing aircraft power layout structure, which comprises: a single-blade rotor 6, a load cabin 1, a driving propeller 5, a rotor shaft 3, and a flapping shaft 2.

[0010] The main body of the power layout structure is a single-blade rotor 6 with only one blade, one side of the rotor shaft 3 of the single-blade rotor 6 is a load cabin 1 for loading and counterweight, and the other side is provided with a constant pitch rotor blade with a flapping shaft 2, the rotor blade is arranged to be flappable around the flapping shaft 2; the rotor blade is provided with a driving propeller 5 for driving the single-blade rotor 6 to rotate or generate level flight thrust.

[0011] In the vertical take-off state, the single-blade rotor 6 rotates to generate hovering lift.

[0012] In the cruising and level flight state, the single-blade rotor 6 is locked and used as a fixed-wing wing.

[0013] Among them, through the unbalanced design of the single-blade rotor 6, the load cabin 1 and the driving propeller 5, the single-blade rotor 6 with the driving propeller 5 eliminates the unbalanced force and moment of the single-blade rotor 6 when it is in stable motion, i.e., when the rotational speed is constant, so that the single-blade rotor 6 works in a form close to axisymmetric rotor.

[0014] Among them, the unbalanced design offsets the unbalanced aerodynamic force, inertial force and other forces through the unbalance of mass, aerodynamic force and inertial force, so that the design result is relatively balanced in the overall force and moment.

[0015] The layout structure is designed to stabilize the single-blade rotor in a manner close to the shaft-symmetrical rotor in the steady-state hovering state, and to reduce the unbalance, by using the following unbalance design:

[0016] 1) First, the mass is reasonably distributed and designed so that the power layout is mass statically balanced around the rotor rotation shaft 3;

[0017] 2) In the case of mass static balance, the mass center of one side of the load cabin 1 is moved downward along the rotor rotation shaft 3, and the mass center of one side of the driving propeller 5 is moved upward, so that the mass dynamic unbalance moment generated by the single-blade rotor 6 in the rotation process is balanced with the lift moment generated by the single-blade rotor 6 around the flapping rotation shaft 2;

[0018] 3) The driving propeller 5 thrust axis is arranged at the average aerodynamic chord of the single-blade rotor 6, so that the driving propeller thrust and the single-blade rotor aerodynamic torque are balanced around the rotor rotation shaft, and at the same time, the driving propeller thrust and the single-blade rotor aerodynamic torque are balanced by themselves;

[0019] 4) According to the gyroscopic moment of the propeller angular momentum and the rotation direction of the rotor, the rotation direction of the driving propeller is selected, so that the propeller gyroscopic moment generates a gyroscopic moment that lifts the single-blade rotor;

[0020] 5) The mass distribution of the driving propeller, the motor on the driving propeller, and the components of the single-blade rotor is designed so that the inertia product around the rotor rotation shaft in the rotor cross-sectional direction is a reasonable value, and the dynamic unbalance moment generated by the reasonable value is in the rotor pitch direction, and the size is just balanced with the propeller gyroscopic moment that lifts the single-blade rotor and the rotor airfoil aerodynamic moment that lowers the single-blade rotor.

[0021] Through the above unbalance design, the single-blade rotor power layout can eliminate the unbalanced force and the unbalanced moment; since the aerodynamic moment, the gyroscopic moment, and the dynamic unbalance moment are all in the square relationship with the rotation speed, the balanced layout obtained at the design point is also balanced at other rotation speeds.

[0022] The driving propeller 5 thrust axis is arranged at the average aerodynamic chord of the single-blade rotor 6, specifically at 0.75 times the radius of the single-blade rotor 6.

[0023] The single-blade rotor 6 is a component that generates lift during vertical take-off and cruising flight, and its design features take into account the characteristics of the wings of conventional fixed-wing aircraft and the rotors of helicopters, and uses the design means of wing tip twist, variable chord, variable airfoil, and rear sweep, with the fixed-wing cruising efficiency as the main design point, and taking into account the rotor hovering efficiency.

[0024] The load cabin 1 is used for loading single-blade rotor control system electronic components, plays a role of single-blade rotor mass static balance, dynamic balance trimming, and can also balance the waving effect caused by rotor lift; the load cabin 1 is designed according to the cruise state and has a fairing shape.

[0025] The driving propeller 5 is used for providing driving force for rotor rotation or cruise flight, and is arranged to balance rotor torsion and gyroscopic moment.

[0026] The single-blade rotor 6 is arranged to be rotatable around the rotor rotation shaft 3 and waveable around the waving shaft 2.

[0027] (Three) beneficial effects

[0028] The single-blade rotor vertical take-off and landing fixed-wing aircraft power layout structure provided by the application has the following beneficial effects:

[0029] Compared with the prior art, the beneficial effects of the application are embodied in the following five aspects:

[0030] (1) lower hovering power consumption per unit lift

[0031] 1) Compared with the vertical take-off and landing aircraft using multiple rotors, the single-blade rotor power layout has a larger rotor disc area, lower rotor disc load, and higher lift-power ratio;

[0032] 2) Compared with the tilt propeller / tilt rotor aircraft, the single-blade rotor power layout has a single hovering design point, avoiding the design point contradiction caused by horizontal cruise flight.

[0033] (2) higher horizontal flight propulsion efficiency

[0034] Compared with tilt propeller / tilt rotor aircraft, the single rotor power layout has no design point contradiction between hovering and cruising, and higher propulsion efficiency.

[0035] (3) Higher cruising efficiency

[0036] 1) Compared with multi-rotor aircraft, the number of useless propellers is less, and the interference drag is smaller.

[0037] 2) Compared with tilt rotor aircraft, the wing aspect ratio is larger, and the lift-drag ratio is higher.

[0038] 3) The single rotor power layout uses one driving propeller to complete the rotor driving in hovering state and to overcome resistance in cruising flight, and has higher power utilization efficiency.

[0039] (4) Less dead weight

[0040] Compared with multi-rotor aircraft, the power of useless propellers in cruising state is less.

[0041] Compared with tilt propeller / tilt rotor aircraft, there is no tilting mechanism.

[0042] (5) Good balance after unbalanced design

[0043] The unbalanced design method can make the power layout balanced in the overall force and moment, and can make the single rotor power system work in a way close to the conventional axisymmetric rotor. Therefore, compared with the single rotor without unbalanced design, it has the advantages of good stability, good symmetry and small vibration / shaking. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a single rotor vertical take-off and landing fixed-wing aircraft power layout composition diagram; 1-load cabin; 2-waving shaft; 3-rotor shaft; 4-propeller shaft; 5-driving propeller; 6-single rotor.

[0045] Figure 2 is a single rotor vertical take-off and landing fixed-wing aircraft power layout schematic diagram;

[0046] Figure 3 is a driving propeller design parameter;

[0047] Figure 4 is a coordinate system schematic diagram;

[0048] Figure 5 is the result of asymmetric characteristic analysis of the reference configuration;

[0049] Among them, Figure 5(a) is the rotor speed and waving angle; Figure 5(b) is the force and moment of the rotor yi axis;

[0050] Figure 6 is a design configuration asymmetry analysis result. DETAILED DESCRIPTION

[0051] In order to make the purpose, content and advantages of the present application more clear, the specific embodiments of the present application are described in further detail below in combination with the drawings and examples.

[0052] In order to solve the above technical problems, the present application provides a single-blade rotor type vertical take-off and landing fixed-wing aircraft power layout structure, as shown in the figure, the power layout structure comprises a single-blade rotor 6, a load cabin 1, a driving propeller 5 (including a motor), a rotor rotating shaft 3, a flapping rotating shaft 2. Figure 1

[0053] The main body of the power layout structure is a single-blade rotor 6 with only one blade, one side of the rotor rotating shaft 3 of the single-blade rotor 6 is a load cabin 1 for loading and counterweight, and the other side is provided with a constant pitch rotor blade with a flapping rotating shaft 2, and the rotor blade is arranged to be flappable around the flapping rotating shaft 2; the rotor blade is provided with a driving propeller 5 for driving the single-blade rotor 6 to rotate or generate a level flight thrust.

[0054] In the vertical take-off and landing state, the single-blade rotor 6 rotates to generate a hovering lift.

[0055] In the cruising and level flight state, the single-blade rotor 6 is locked and used as a fixed-wing wing.

[0056] Among them, through the unbalance design of the single-blade rotor 6, the load cabin 1 and the driving propeller 5, the single-blade rotor 6 with the driving propeller 5 is in stable motion, that is, the rotating speed is constant, the unbalanced force and moment of the single-blade rotor 6 are eliminated, and the single-blade rotor 6 works in the form of an approximately axisymmetric rotor.

[0057] Among them, the unbalance design offsets each other through the unbalance of mass, aerodynamic force and inertial force, so that the design result is relatively balanced in the overall resultant force and moment, although the unbalanced aerodynamic force and inertial force are generated.

[0058] Among them, in order to make the single-blade rotor in a stable hovering state move stably in the form of an approximately axisymmetric rotor and reduce the unbalance, the following unbalance design is adopted:

[0059] 1) First, through reasonable mass distribution design, the power layout is mass statically balanced around the rotor rotating shaft 3;

[0060] 2) Under the condition of mass static balance, by moving the mass center of one side of the load cabin 1 downward along the rotor rotating shaft 3 and moving the mass center of one side of the driving propeller 5 upward, the mass dynamic unbalance moment generated by the single-blade rotor 6 in the rotating process is balanced with the lift moment generated by the single-blade rotor 6 around the flapping rotating shaft 2.​

[0061] 3) The driving propeller 5 thrust axis is arranged at the average aerodynamic chord of the single-blade rotor 6, so that the driving propeller thrust and the single-blade rotor aerodynamic torque are balanced around the rotor rotation axis, and the driving propeller thrust and the single-blade rotor aerodynamic torque are also balanced by themselves;

[0062] 4) According to the gyroscopic torque of the propeller angular momentum and the rotor rotation direction, the driving propeller rotation direction is selected, so that the propeller gyroscopic torque generates a gyroscopic torque that lifts the single-blade rotor;

[0063] 5) The mass distribution of the driving propeller, the motor on the driving propeller, and the single-blade rotor is designed, so that the inertia product around the rotor rotation axis in the rotor cross-sectional direction is a reasonable value, and the dynamic unbalance torque generated by the reasonable value is in the rotor pitch direction, and the size is just balanced with the lifting propeller gyroscopic torque and the low head rotor airfoil aerodynamic torque.

[0064] Wherein, through the above unbalanced design, the single-blade rotor power layout can eliminate the unbalanced force and the unbalanced torque; since the aerodynamic torque, the gyroscopic torque, and the dynamic unbalance torque are all in the square relationship with the rotation speed, the balanced layout obtained at the design point is also balanced at other rotation speeds.

[0065] Wherein, the driving propeller 5 thrust axis is arranged at the average aerodynamic chord of the single-blade rotor 6, specifically at 0.75 times the radius of the single-blade rotor 6.

[0066] Wherein, the single-blade rotor 6 is a component that generates lift during vertical take-off (rotor mode) and cruise flight (fixed-wing mode), and its design features take into account the characteristics of conventional fixed-wing aircraft wings and helicopter rotors, and adopts wing tip twist, variable chord, variable airfoil, and sweepback design methods, taking fixed-wing cruise efficiency as the main design point, and taking into account rotor hovering efficiency.

[0067] Wherein, the load cabin 1 is used to load single-blade rotor control system electronic components, and plays a role in static balance and dynamic balance of the single-blade rotor, and can also balance the waving effect caused by the rotor lift; the load cabin 1 is designed according to the cruise state.

[0068] Wherein, the driving propeller 5 is used to provide driving force for rotor rotation (rotor mode) or cruise flight (fixed-wing mode), and its layout design is used to balance the rotor torque and gyroscopic torque.

[0069] Wherein, the single-blade rotor 6 is arranged to be rotatable around the rotor rotation axis 3 and waveable around the waving axis 2.

[0070] Embodiment 1

[0071] The application examples are further described in detail below with reference to the accompanying drawings and examples.

[0072] 1. Basic configuration of single rotor power system

[0073] A simple parameter model of single rotor power system is established, as shown in Figure 2 The rotor span is 1.5 m, the airfoil is Clark Y airfoil, the chord length b is 0.25 m, the blade installation angle is 8° in hover state, and there is no twist in spanwise direction. The illustrated rotor can be used as the right rotor of an aircraft. It is assumed that the single rotor power system needs to provide more than 600 N of lift in hover state (the required speed is about 800 r / min).

[0074] The selection of the design parameters of the drive propeller needs to consider the following aspects: (1) power balance, i.e., the drive propeller tension and rotor torsion are offset in a stable state, which requires the drive propeller to be located at the average aerodynamic chord of the rotor (about 0.75R in spanwise direction); (2) propeller tip Mach number limit, the present application limits the propeller tip Mach number to be not higher than 0.55, around 0.5; (3) maintain acceptable propeller efficiency, generally higher than 75%.

[0075] According to the above requirements, the propeller design parameters are selected as follows: altitude H = 0 m, incoming flow speed V = 100 m / s, rotation speed n = 7500 r / min, diameter D = 0.36 m, and number of blades NB = 4. The design method is the blade element momentum theory, and the design results are shown in Figure 3 In the figure, R is the radius of the propeller, r, b, and θ are the blade element radial position, chord length, and twist angle, respectively.

[0076] A propeller disc reference frame Oxiyizi rotating with the rotor is established, the origin of the reference frame is located at the center of mass, the Oxi axis points downward along the rotor rotation axis, the rotor rotates along the -Oxi axis, the Oyi axis points to the tip side perpendicular to the Oxi axis, and the Ozi axis is determined by the right-hand rule, which is the flapping axis of the rotor. The coordinate system is shown in Figure 4 .

[0077] The inertia tensors and centers of mass of various components are shown in the following table, in which the inertia tensors are described in the center of mass reference frame of each component.

[0078] Table 1 Mass parameters of initial configuration components

[0079]

[0080] 2. Unbalanced design

[0081] To reduce the rotor's flapping and pitching moment, it is necessary to reduce the rotor's xy inertia product Ixy (negative increase) and increase the rotor's xz inertia product Ixz by a small amount. There are many ways to achieve this, the most convenient of which is to move the drive-paddle-motor position (while adjusting the load compartment trim). As an illustrative design, on the basis of the reference configuration, the present invention moves the motor-drive-paddle upward (-x axis) by 110 mm (the load compartment is correspondingly lowered by 2.5 mm) to adjust Ixz, and moves the motor-drive-paddle forward (-z axis) by 308 mm (the load compartment is correspondingly moved backward by 7.1 mm) to adjust Ixy.

[0082] After the position adjustment, the system's overall center of gravity position and inertia tensor become:

[0083] CG total = [0.7927, -0.5010, 0.1704] x 10 -6

[0084]

[0085] 3. Effect of unbalanced design

[0086] The reference configuration of the single-blade rotor power system without design is analyzed. At sea level, at different drive-paddle speeds np, the rotor speed nw, the flapping angle θ, and the yi-axis force Fy and the moment My on the rotor's rotation axis are shown in Fig. 5(b).

[0087] The single-blade rotor power system with unbalanced design is analyzed. The calculation conditions are the same as those of the reference configuration, and the calculation results are shown in Figure 6 . The speed is almost the same as that of the reference configuration, and the flapping angle is a constant value of 0.082 degrees, so these two sets of curves are not shown.

[0088] It can be seen that (1) after the mass distribution unbalanced design, the flapping angle and the y-axis unbalanced force and moment are significantly reduced and close to zero. Through quantitative analysis of this example, it can be seen that the mass distribution design can already make the unbalanced force and moment close to zero, indicating that the unbalanced design method described in the present invention is feasible. (2) Through unbalanced design, the single-blade rotor with a drive paddle can eliminate the unbalanced force and moment of the single-blade rotor during stable motion (constant speed), so that the single-blade rotor works in a form close to that of a symmetrical rotor.

[0089] The above only describes the preferred embodiments of the present invention. It should be noted that for those skilled in the art, without departing from the technical principles of the present invention, a number of improvements and modifications can be made, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A single rotor vertical take-off and landing fixed wing aircraft power layout configuration, characterized in that, The power layout structure comprises a single-blade rotor (6), a load cabin (1), a driving propeller (5), a rotor rotating shaft (3), and a flapping rotating shaft (2); The main body of the power layout structure is a single-blade rotor (6), one side of the rotor rotating shaft (3) of the single-blade rotor (6) is a load cabin (1) for loading and counterweight, and the other side is provided with a constant pitch rotor blade with a flapping rotating shaft (2), the rotor blade is arranged to be flappable around the flapping rotating shaft (2); the rotor blade is provided with a driving propeller (5) for driving the single-blade rotor (6) to rotate or generate a level flight thrust; In the vertical take-off and landing state, the single-blade rotor (6) rotates to generate a hovering lift; In the cruising level flight state, the single-blade rotor (6) is locked and used as a fixed wing; The single-blade rotor (6), the load cabin (1), and the driving propeller (5) are designed to be unbalanced, the single-blade rotor (6) with the driving propeller (5) is in stable motion, i.e., the rotating speed is constant, the unbalanced force and moment of the single-blade rotor (6) are eliminated, and the single-blade rotor (6) works in the form close to an axisymmetric rotor; The unbalanced design is achieved by the mutual offset of the unbalance of mass, aerodynamic force, and inertial force, so that the design result is relatively balanced in the overall resultant force and moment, although the unbalanced aerodynamic force and inertial force are generated; In order to make the single-blade rotor work in the form close to an axisymmetric rotor in the steady hovering state and reduce the unbalance, the following unbalanced design is adopted: 1) The mass is reasonably distributed to make the power layout statically balanced around the rotor rotating shaft (3); 2) In the case of static mass balance, the mass center of one side of the load cabin (1) is moved downward along the rotor rotating shaft (3), and the mass center of one side of the driving propeller (5) is moved upward, so that the mass dynamic unbalanced moment generated by the single-blade rotor (6) in the rotating process is balanced with the lift moment generated by the single-blade rotor (6) around the flapping rotating shaft (2); 3) The driving propeller (5) thrust axis is arranged at the average aerodynamic chord of the single-blade rotor (6), so that the driving propeller thrust and the single-blade rotor aerodynamic torque are balanced around the rotor rotating shaft, and the driving propeller thrust and the single-blade rotor aerodynamic torque are balanced by themselves; 4) According to the gyroscopic moment of the propeller angular momentum and the rotating direction of the rotor, the rotating direction of the driving propeller is selected, so that the propeller gyroscopic moment generates a gyroscopic moment that lifts the single-blade rotor; 5) The mass distribution of the driving propeller, the motor on the driving propeller, and the components of the single-blade rotor is designed, so that the inertia product around the rotor rotating shaft in the cross section direction of the rotor is a reasonable value, the dynamic unbalanced moment generated by the reasonable value is in the rotor pitch direction, and the size is balanced with the lifting propeller gyroscopic moment and the low single-blade rotor aerodynamic moment. Wherein, through the above non-equilibrium design, the single rotor power layout can eliminate the unbalanced force and the unbalanced moment; since the aerodynamic moment, the gyroscopic moment and the dynamic unbalanced moment are all in the square relationship with the rotating speed, the balanced layout obtained at the design point is also balanced at other rotating speeds; Wherein, the driving propeller (5) thrust axis is arranged at the average aerodynamic chord of the single rotor (6), specifically at 0.75 times the radius of the single rotor (6); Wherein, the single rotor (6) is a component for generating lift during vertical take-off and cruising, and its design features take into account the features of the conventional fixed-wing aircraft wing and the helicopter rotor, adopts the design means of wing tip twist, variable chord, variable airfoil and sweepback, and takes the fixed-wing cruising efficiency as the main design point, and takes into account the rotor hovering efficiency; Wherein, the load cabin (1) is used to load the single rotor control system electronic components, and plays the role of single rotor mass static balance, dynamic balance trimming, and can also balance the waving effect caused by the rotor lift; the load cabin (1) is designed according to the cruise state design fairing; Wherein, the driving propeller (5) is used to provide driving force for rotor rotation or cruising flight, and its layout design is used to balance the rotor torsion and gyroscopic moment; Wherein, the single rotor (6) is arranged to be rotatable around the rotor rotating shaft (3) and waveable around the waving shaft (2).

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