A non-rotationally symmetrical propeller, powered rotor and aircraft

Abstract

The present application discloses a non-rotationally symmetric propeller, a powered rotor, and an aircraft. The structure of the propeller has non-rotational symmetry relative to the center of rotation, and the plurality of blades include at least one variable thrust blade, and the thrust torque generated by the variable thrust blade relative to the center of rotation of the propeller is not equal to the thrust torque generated by other blades. The powered rotor includes a non-rotationally symmetric propeller and a motor that adjusts the rotation speed at a specific angle. The present application innovatively utilizes non-rotationally symmetric propellers and speed-regulating motors to allow the propeller to generate a tilt torque in any direction of the rotation plane, and through vector adjustment of the tilt torque, the steering flexibility of the powered rotor and the maneuverability, attitude stability, and flight efficiency of the aircraft are greatly improved, bringing new breakthroughs and development opportunities to the design of powered rotors and aircraft.

Description

Technical Field

[0001] The present application relates to the field of powered rotors, and in particular to a non-rotationally symmetrical propeller, powered rotor and aircraft. Background Art

[0002] The propellers of a power rotor are usually rotationally symmetrical, the purpose of which is to ensure that the thrust of the rotor is equal at any angle, so that the average thrust of the rotor is located on the axis of the rotation shaft, and its average tilting torque is zero. It can be seen that the thrust direction of a conventional power rotor based on a rotationally symmetrical propeller is fixed, and the thrust direction cannot be adjusted. Using two or more power rotors can achieve vector adjustment of the combined thrust (that is, its direction and size can be adjusted at the same time), but the power device becomes complicated, and there are many problems such as a large number of motors and propellers, a large moment of inertia, a large flight resistance, and inconvenient installation. Summary of the invention

[0003] In response to the problems existing in the prior art, the present application proposes a power rotor technology based on a non-rotationally symmetric propeller. The power rotor can not only achieve axial thrust, but also achieve a tilting torque with controllable size and direction. It can realize a steerable thrust system that does not require a mechanical steering structure and has the advantages of simple structure and high reliability.

[0004] A first aspect of the present invention provides a non-rotationally symmetric propeller, the structure of the propeller having non-rotational symmetry relative to a rotation center, the propeller having several blades including at least one variable thrust blade, the thrust torque generated by the variable thrust blade relative to the rotation center of the propeller being unequal to the thrust torque generated by other blades.

[0005] Furthermore, the non-rotationally symmetric propeller is equivalent to a combination of a rotationally symmetric propeller and a single-blade propeller, the single-blade propeller generates a tilting torque when rotating, and the tilting torque of the single-blade propeller is equal to the tilting torque of the non-rotationally symmetric propeller.

[0006] Furthermore, the variable thrust blade includes a thrust increasing blade and a thrust reducing blade, the thrust increasing blade generates a thrust torque greater than other blades, and the thrust reducing blade generates a thrust torque less than other blades. The propeller also includes a horizontal thrust blade, and at least one shape parameter of the variable thrust blade is different from that of the horizontal thrust blade, and the shape parameter includes a three-dimensional shape and geometric parameters of the blade, and the geometric parameters include length, width, thickness and blade angle.

[0007] Furthermore, if the propeller is a two-blade propeller, it is equivalent to a rotationally symmetrical two-blade propeller and a single-blade propeller; the thrust f of the equivalent single-blade propeller is d (ω) and the lever arm l d The calculation formula is:

[0008]

[0009] Among them, the thrust of the flat-thrust blade is f0(ω), and the lever arm relative to the rotation center of the propeller is l0. The variable-thrust blade is located at an angle θ1, and its thrust is f1(ω). The lever arm relative to the rotation center of the propeller is l1, and the angle of the equivalent single-blade propeller is θ1.

[0010] Furthermore, the propeller is a multi-blade propeller including a flat-thrust blade and a variable-thrust blade, which is equivalent to a rotationally symmetrical full-flat-thrust blade propeller and a single-blade propeller; the angle θ of the equivalent single-blade propeller is d The calculation formula is:

[0011]

[0012] Equivalent single-blade propeller thrust f d (ω) and the lever arm l d The calculation formula is:

[0013]

[0014] Where N is the total number of propeller blades, and the nth blade is located at an angle θ n , whose thrust is f n (ω), the moment arm relative to the propeller's rotation center is l n The thrust of the propeller blade is f0(ω), and the moment arm relative to the rotation center of the propeller is l0.

[0015] In a second aspect, the present application further provides a powered rotor, comprising a non-rotationally symmetrical propeller and a motor as described in the first aspect, wherein the propeller is mounted on the rotating shaft of the motor, and the motor is adjusted for a rotation speed at a specific angle. If the motor speed drives the propeller to rotate in a centrally symmetrical angular distribution, the propeller does not generate a tilting torque relative to its rotation center; if the motor speed drives the propeller to rotate in a non-centrally symmetrical angular distribution, the propeller generates a non-zero tilting torque relative to its rotation center; the motor performs vector adjustment on the tilting torque by adjusting the angular distribution of the speed.

[0016] Furthermore, the tilting moment M t The calculation formula is:

[0017]

[0018] Where ω(θ) is the angular distribution function of the motor angular velocity, θ t is the tilting moment M t The angle in the plane of rotation relative to the x-axis is given by the following equation:

[0019]

[0020] Furthermore, the motor drives the propeller to rotate at a non-uniform speed at a specific angle in a non-center-symmetric speed distribution manner, including an acceleration mode, a deceleration mode, and a complementary drive mode using both acceleration and deceleration.

[0021] Furthermore, the angle distribution function of the motor angular velocity is a positive-valued periodic function, and the periodic function includes a sine function, a cosine function or a linear combination thereof.

[0022] Furthermore, the power rotor control system includes a digital control system and a motor drive circuit. The digital control system obtains the angular position and angular velocity of the motor rotor through a sensor, and controls the generation of the motor drive current through the speed regulation port of the motor drive circuit or the control port of the inverter circuit, thereby adjusting the speed of the motor at any angle.

[0023] Furthermore, if the motor is connected to the mounting base via a universal joint, the powered rotor can be tilted at any angle in the rotation plane; if the motor is fixed to the base via a tilt shaft, the powered rotor can be tilted in one direction.

[0024] In a third aspect, the present application further provides a twin-rotor aircraft, comprising the power rotor described in the second aspect of the present invention, wherein the power rotors are installed in a front-to-back arrangement in the flight direction, and the flight attitude is controlled by adjusting the thrust and tilt torque of the power rotors.

[0025] In a fourth aspect, the present application further provides a fixed-wing aircraft, comprising a plurality of powered rotors as described in the second aspect of the present invention, wherein the powered rotors are installed laterally symmetrically in the aircraft and can achieve conversion and control of vertical and horizontal flight attitudes by adjusting the thrust and tilt torque of the powered rotors.

[0026] This application has at least the following beneficial effects:

[0027] Vector control of the tilt torque: By adjusting the angular distribution of the propeller angular velocity, especially by using the sine (or equivalent cosine, triangle wave, trapezoidal wave, square wave) modulation of the angular velocity, vector control of the propeller tilt torque can be achieved. This means that the size and direction of the tilt torque can be precisely adjusted as needed, realizing the electronically controlled pitch function of the powered rotor, and enhancing the steering flexibility, maneuverability and attitude control accuracy of the aircraft. Specifically, changing the average angular velocity and the degree of modulation can adjust the size of the tilt torque, while changing the specific angle of the angular velocity distribution can change the direction of the tilt torque. This adjustment method enables the aircraft to respond more flexibly to various flight requirements and environmental changes.

[0028] Advantages of complementary drive mode: The complementary drive mode increases the angular velocity of the equivalent single-blade propeller near a specific angle and reduces the angular velocity near its central symmetric angle, which not only achieves a greater tilt torque but also keeps the average angular velocity of the propeller unchanged. This drive mode improves performance while ensuring the stability and controllability of the aircraft.

[0029] Improve the maneuverability of the aircraft: The present invention enables the aircraft to achieve various maneuvers such as rolling, pitching and yaw by adjusting the tilting torque of the propeller. For example, in a helicopter or similar aircraft, by adjusting the speed difference of different rotors, the body can be rolled and turned, thereby enhancing the maneuverability and flexibility of the aircraft.

[0030] Adaptable to various application scenarios: The present invention is not only applicable to traditional helicopters and fixed-wing aircraft, but also to new aircraft such as tandem twin-rotor aircraft, transverse twin-rotor fixed-wing aircraft and tilt-rotor aircraft. By optimizing the design of propellers and powered rotors, the performance of these aircraft can be improved in various scenarios such as vertical take-off and landing, high-speed cruising, and low-altitude flight.

[0031] Improve flight efficiency: Through precise control of the propeller angular velocity distribution, the tilt torque can be vectored through a single propeller, which not only simplifies the mechanical structure, but also reduces resistance and empty weight, and improves flight efficiency. Especially in complex flight missions, this optimization can significantly improve the maneuverability and endurance of the aircraft.

[0032] To summarize, the technical solution of the present application designs a controllable variable pitch powered rotor by innovatively utilizing non-rotationally symmetric propellers and motor speed control technology, thereby overcoming the technical bias of propeller symmetry design in the prior art and achieving precise vector control of the tilt torque of the powered rotor or aircraft, thereby improving the steering flexibility, maneuverability, attitude stability and propulsion efficiency of the aircraft, and bringing new breakthroughs and development opportunities to the field of powered rotor and aircraft design. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The force and equivalent model of a non-rotationally symmetric two-blade propeller

[0034] Figure 2 The force and equivalent model of non-rotationally symmetric multi-blade propeller

[0035] Figure 3 The thrust distribution and equivalent axial force and tilting moment of a single-blade propeller

[0036] Figure 4 It is a driving mode in which a single-blade propeller realizes a tilt torque.

[0037] Figure 5It is a power rotor and feedback control system based on a non-rotationally symmetric propeller.

[0038] Figure 6 It is a power rotor and feedback control system based on a non-rotationally symmetric propeller.

[0039] Figure 7 It is an omnidirectional tilt-rotor based on a non-rotationally symmetric propeller.

[0040] Figure 8 It is an omnidirectional tilt-rotor based on a non-rotationally symmetrical propeller.

[0041] Fig. 9 It is a unidirectional tilt-rotor based on a non-rotationally symmetrical propeller.

[0042] Fig.10 It is a coaxial tilt-rotor

[0043] Fig.11 It is a tandem twin-rotor helicopter based on an electronically controlled variable-pitch powered rotor.

[0044] Fig.12 It is a transverse twin-rotor fixed-wing aircraft based on an electronically controlled variable-pitch powered rotor. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. It is understood that the specific embodiments described herein are only used to explain the related applications, rather than to limit the applications. It should also be noted that, for ease of description, only the parts related to the related applications are shown in the drawings.

[0046] Embodiment 1

[0047] A non-rotationally symmetrical propeller, wherein the structure of the propeller has non-rotational symmetry relative to the rotation center, wherein the propeller has several blades including at least one variable thrust blade, wherein the thrust torque generated by the variable thrust blade relative to the rotation center of the propeller is not equal to the thrust torque generated by other blades. A non-rotationally symmetrical propeller means that the structure of the propeller does not have rotational symmetry relative to its rotation center, and under the same rotation speed, the thrust torque generated by at least one blade therein (relative to the rotation center of the propeller) is not equal to the thrust torque generated by other blades (relative to the rotation center of the propeller).

[0048] Furthermore, for the convenience of description, the blade with a thrust torque different from that of other blades is called a variable thrust blade, and the blade with a thrust torque greater than that of other blades is called an increased thrust blade, and the blade with a thrust torque less than that of other blades is called a reduced thrust blade, and the other blades except the variable thrust blade are called flat thrust blades.

[0049] Furthermore, the variable thrust blade can achieve a change in thrust torque by changing the three-dimensional shape or shape parameters of the blade, such as at least one of the length (radius), width, thickness or blade angle (pitch) of the blade.

[0050] For a two-blade propeller, assuming that the thrust of the horizontal thrust blade is f0(ω), the moment arm relative to the rotation center of the propeller is l0, and the variable thrust blade is located at an angle θ1, its thrust is f1(ω), and the moment arm relative to the rotation center of the propeller is l1, then it can be equivalent to a rotationally symmetric propeller consisting of two horizontal thrust blades and an additional single-blade propeller, such as Figure 1 As shown. Among them, the angle of the single-blade propeller is θ1, and the thrust of the single-blade propeller is f d (ω) and the lever arm l d They are:

[0051]

[0052] For a multi-blade propeller, assume that the propeller includes a flat thrust blade and a variable thrust blade, the total number of blades is N, and the nth blade is located at an angle θ n , the thrust and lever arm are f n (ω) and l n , if the thrust of the horizontal push blade is f0(ω) and the moment arm relative to the rotation center of the propeller is l0, then the propeller can be equivalent to a rotationally symmetric propeller consisting of N horizontal push blades and an additional single-blade propeller, such as Figure 2 As shown. Among them, the single-blade propeller is located at an angle θ d , which is determined by the following equation:

[0053]

[0054] The thrust of the single-blade propeller is f d (ω) and the lever arm l d They are:

[0055]

[0056] For an equivalent rotationally symmetrical propeller, regardless of the motor speed, its thrust f0 is symmetrically distributed on a circle with a force arm l0 as the radius, so its tilting moment relative to the propeller's rotation center is zero, which is equivalent to all the propeller's thrust acting on the rotation axis. For the sake of convenience, this force equivalent to acting on the rotation axis with the resultant moment relative to the propeller's rotation center being zero is called axial force.

[0057] Embodiment 2

[0058] A power rotor comprises a non-rotationally symmetrical propeller and a motor as described in Example 1, wherein the propeller is mounted on the rotating shaft of the motor, and the motor is adjusted for a rotation speed at a specific angle. A power rotor with the ability to vector-regulate the tilt torque is composed of a non-rotationally symmetrical propeller and a motor with an angle speed regulation function, wherein the propeller is mounted on the rotating shaft of the motor and can rotate under the drive of the motor to obtain thrust (or pulling force).

[0059] Furthermore, a motor with an angle speed regulation function means that the motor can not only regulate the average motor speed, but also regulate the motor speed at a specific angle (or angle range).

[0060] For an equivalent single-blade propeller, if the motor rotates at a uniform speed at all angles or rotates non-uniformly in a centrally symmetrical manner, the thrust f of the single-blade propeller is d With force arm l d The average thrust of the propeller during one rotation does not produce a tilting moment, such as Figure 3 As shown in (a) and (b).

[0061] However, if the motor speed is distributed in a non-centrosymmetric manner at each angle, the thrust f of a single-blade propeller d With force arm l d The distribution is non-centrally symmetrical on the circumference of the radius, so the tilting moment relative to the propeller rotation center is not zero. In other words, the thrust of the propeller during one rotation can not only provide axial force, but also provide tilting moment, such as Figure 3 Assume that the angular velocity at angle θ is ω(θ), then the resulting tilting moment of the single-blade propeller is located in the rotation plane and the angle with the x-axis is θ t , whose size is:

[0062]

[0063] Among them, the angle θ t Determined by the following equation:

[0064]

[0065] From the above theory, we can know that the magnitude of the tilting moment of a single-blade propeller is M t and orientation θ t It is determined by the angular distribution function ω(θ) of the angular velocity. That is to say, by adjusting the angular distribution law of the motor angular velocity, the propeller tilt torque can be vector-adjusted.

[0066] Furthermore, in order to realize the tilting moment, three methods can be used, such as Figure 4 As shown. The first is the acceleration mode, which increases the angular velocity of the equivalent single-blade propeller near a specific angle (relative to other angles); the second is the deceleration mode, which reduces the angular velocity of the equivalent single-blade propeller near a specific angle (relative to other angles); the third is a complementary drive mode that uses both acceleration and deceleration, that is, increasing the angular velocity of the equivalent single-blade propeller near a specific angle (relative to other angles), while reducing the angular velocity of the equivalent single-blade propeller near the central symmetric angle of the specific angle (relative to other angles). Obviously, all three adjustment methods can achieve vector adjustment of the tilt torque. The angle of the tilt torque can be adjusted by adjusting the angle of acceleration or deceleration, and the magnitude of the tilt torque can be adjusted by adjusting the intensity of acceleration or deceleration.

[0067] It should be pointed out that: (1) The so-called equivalent single-blade propeller actually corresponds to a specific angular position of a non-rotationally symmetric propeller, namely, θ d (2) Since the tilt torque of the equivalent rotationally symmetric propeller is zero, the tilt torque obtained by the equivalent single-blade propeller is actually the tilt torque of the non-rotationally symmetric propeller. (3) Since the complementary drive mode can not only achieve a larger tilt torque, but also keep the average angular velocity of the propeller unchanged during one rotation, it is the preferred way to achieve the tilt torque.

[0068] Furthermore, in order to achieve a larger tilting torque and maintain the continuity and smoothness of the angular velocity change, the angular velocity distribution function based on the complementary driving mode is:

[0069] ω(θ)=ω0(1+βsin(θ M -θ))(0≤β<1)

[0070] Among them, ω0 is the average angular velocity of one rotation, β is the modulation degree of the angular velocity distribution function, and θ M represents a specific angle, and θ is the azimuth angle of the single-blade propeller. According to mathematical common sense, the sine function in the angular velocity distribution function can be replaced by an equivalent cosine function, or a triangular wave, trapezoidal wave or square wave function that is similar to the sine or cosine function.

[0071] Taking a non-rotationally symmetric two-blade propeller as an example, under the angular velocity distribution condition, the tilting torque that the propeller can provide is located at θ M The angle direction is:

[0072] M t (θ M )=βf d (ω0)l d =β(f1(ω0)l1-f0(ω0)l0)

[0073] Therefore, when the propeller parameters are fixed, the tilting torque can be adjusted by changing the average angular velocity ω0 and the modulation index β, and the angle θ M In other words, by adopting the sinusoidal modulation method of angular velocity, the non-rotationally symmetric propeller can realize the vector control of the tilt torque.

[0074] It should be noted that, for the above-mentioned propellers, the axial thrust is the sum of the axial thrusts of the blades. In addition, the modulation function of the angular velocity can adopt a cosine function equivalent to a sine function, or a triangular wave, trapezoidal wave or square wave function similar to a sine function.

[0075] A power rotor system based on a non-rotationally symmetric propeller Figure 5 As shown, 1 is the horizontal thrust blade of the propeller, 2 is the thrust-increasing blade of the propeller, and 3 is the motor, which is provided with three-phase or multi-phase drive current by the motor drive circuit, and the motor drive circuit has a digital communication port. The digital processing system obtains the angle (position) and angular velocity information of the motor through the angle sensor, and generates a control signal for speed regulation according to the angle as required, and then controls the motor drive circuit through the digital communication port, thereby adjusting the angular velocity of the motor at various angles. The digital processing system includes a general-purpose single-chip microcomputer (MCU), a programmable logic gate array (FPGA) or a digital signal processor (DSP) system, and also includes a dedicated digital or analog-digital hybrid integrated circuit (ASIC) system.

[0076] Another type of powered rotor system based on a non-rotationally symmetric propeller is Figure 6 As shown, 1 is the horizontal thrust blade of the propeller, 2 is the thrust-increasing blade of the propeller, and 3 is a brushless motor, which is provided with a three-phase or multi-phase AC drive current by an inverter circuit. The digital processing system obtains the angle (position) and angular velocity information of the motor through an angle sensor, and generates a control signal for speed regulation according to the angle as required, and then controls the output current of the inverter circuit through the control port of the inverter circuit, thereby adjusting the angular velocity of the motor at various angles. The digital processing system includes a general-purpose single-chip microcomputer (MCU), a programmable logic gate array (FPGA) or a digital signal processor (DSP) system, and also includes a dedicated digital or analog-digital hybrid integrated circuit (ASIC) system.

[0077] The power rotor system based on the non-rotationally symmetrical propeller provided by the present invention can not only provide a tilt torque, but also has the ability to vector-regulate the tilt torque, and actually provides an electrically controlled variable pitch rotor system similar to the main rotor of a helicopter. For simplicity, the electrically controlled variable pitch power rotor based on the non-rotationally symmetrical propeller is referred to as a variable pitch rotor.

[0078] The application of the variable pitch rotor of the present invention includes the following four aspects: (1) The variable pitch rotor can be used to make a tilt rotor, and the tilt rotor can be tilted in any direction; (2) The variable pitch rotor can be applied to a multi-rotor aircraft or a UAV for vertical take-off and landing, and is used to replace one or more conventional powered rotors without a variable pitch function; (3) The variable pitch rotor can be applied to the propeller of a fixed-wing aircraft, and is used to achieve a certain degree of thrust vectoring; (4) The variable pitch rotor can be applied to the main rotor or tail rotor of a helicopter.

[0079] Furthermore, the variable pitch rotor can be used to manufacture tandem twin-rotor helicopters, transverse twin-rotor or transverse quad-rotor tail-seat fixed-wing aircraft, vertical take-off and landing twin-tilt-rotor fixed-wing aircraft or quad-tilt-rotor fixed-wing aircraft, etc.

[0080] The specific application scenarios of this powered rotor include:

[0081] Specific application scenario 1: omnidirectional tiltable powered rotor

[0082] like Figure 7 As shown, 3 is a motor with an angle speed regulation function, 4 is a non-rotationally symmetrical propeller, 5 is a first tilt axis, 6 is a U-shaped tilt frame, 7 is a second tilt axis, and 8 is a U-shaped fixed base. The motor 3 and the propeller 4 are combined to form a variable pitch power rotor; the motor 3 is rotatably fixed to the U-shaped tilt frame 6 through the first tilt axis 5, and the U-shaped tilt frame 6 is rotatably fixed to the U-shaped base 8 through the second tilt axis 7, and the omnidirectional tilt power rotor is fixed to the aircraft through the U-shaped base 8. The U-shaped tilt frame 6 and the first tilt axis 5 and the second tilt axis 7 actually form a universal joint, and the variable pitch power rotor is connected to the fixed base 8 through the universal joint. Therefore, the variable pitch power rotor can be jointly tilted in two orthogonal directions, that is, it can be tilted in any direction within the angle range limited by the universal joint.

[0083] It should be pointed out that universal joints that can be used for bidirectional or multi-directional tilting can have a variety of structures, including universal joints with orthogonal bidirectional tilting structures and universal joints with non-orthogonal multi-directional tilting structures, such as ring frame universal joints, cross universal joints, ball cage universal joints, ball fork universal joints, etc.

[0084] Figure 8It is another type of omnidirectional tiltable power rotor, wherein 3 is a motor with an angle speed regulation function, 4 is a non-rotationally symmetrical propeller, 5 is a first tilt axis, 6 is a U-shaped tilt frame, and 9 is a second rotating axis fixed on the central axis of the U-shaped frame, which is rotatably fixed to the aircraft through a rotating bearing. The U-shaped tilt frame 6 and the first tilt axis 5 and the second rotating axis 9 form a universal joint, so the variable pitch power rotor can be jointly tilted in two orthogonal directions. The advantage of this universal joint tilt mechanism is that the rotation angle of the second rotating axis 9 is not limited and can be arbitrarily changed within the range of 0 to 360 degrees.

[0085] Specific application scenario 2: One-way tilting powered rotor

[0086] Fig. 9 It is a power rotor system that can realize unidirectional tilting, wherein 3 is a motor with angle speed regulation function, 4 is a non-rotationally symmetrical propeller, 5 is a first tilting axis, and 10 is a U-shaped fixed base. The motor 3 and the propeller 4 constitute a variable pitch power rotor, which can rotate freely around the tilting axis 5 within a certain range and is fixed to the aircraft through the U-shaped base.

[0087] Two unidirectional tilt-rotors can be connected by a common tilt-axis to form a linked unidirectional tilt-rotor, such as Fig.10 As shown, 11 is a tilt-rotor rotating in the forward direction, 12 is a tilt-rotor rotating in the reverse direction, the motors of the two tilt-rotors are rigidly connected to a tilt shaft 13, and the tilt shaft is fixed to the aircraft through at least one rotating bearing 14 and can be freely tilted within a range of 0 to 360 degrees.

[0088] Specific application scenario 3 - tandem twin-rotor helicopter

[0089] Using two longitudinally arranged electric variable pitch powered rotors, a tandem twin rotor helicopter can be made, such as Fig.11As shown. Among them, 15 is an electrically controlled variable pitch powered rotor that rotates clockwise, 16 is an electrically controlled variable pitch powered rotor that rotates counterclockwise, and 17 is the helicopter body. The pitch adjustment of the helicopter in the front and rear directions can be controlled by the average rotation speed of the front and rear rotors 15 and 16. For example, if the rotation speed of the rotor 14 is greater than the rotation speed of the rotor 15, the helicopter body 17 will pitch down (lower its head); otherwise, the helicopter body 17 will pitch up (raise its head). The roll balance of the helicopter on the left and right sides is controlled by the tilting torque of the two electrically controlled variable pitch powered rotors 15 and 16. For example, if the rotation speed of the thrust-increasing blades of the rotors 15 and 16 on the left side of the helicopter is greater than that on the right side, the helicopter body 17 will roll to the right, otherwise, the helicopter body 17 will roll to the left. In addition, by utilizing the average rotation speed difference between the two rotors 15 and 16, a certain degree of turning torque can also be achieved, thereby causing the helicopter to turn. For example, if the rotation speed of the rotor 15 is greater than that of the rotor 16, the helicopter body 17 will obtain a counterclockwise steering torque, otherwise, the helicopter body 17 will obtain a clockwise steering torque.

[0090] Specific application scenario 4 - transverse twin-rotor fixed-wing aircraft

[0091] The structure of a transverse twin-rotor fixed-wing aircraft is as follows Fig.12 As shown, 18 is a variable pitch powered rotor that rotates forward, and 19 is a variable pitch powered rotor that rotates in the opposite direction. The two powered rotors are symmetrically mounted on the wing 20 of the aircraft. The wing 20 is rigidly connected to the fuselage 21 and integrated with each other. There is a pair of V-shaped tail wings 22 on the front and back of the wing ends. The tail of the aircraft is equipped with a support structure that can touch the ground, and the aircraft performs vertical take-off and landing in a tail-seat manner. In the vertical take-off and landing stage, the fixed-wing aircraft is similar to a tandem twin-rotor helicopter. Its left and right balance can be adjusted by the speed difference between the two powered rotors 19 and 20, and the front and rear balance can be adjusted by the tilting torque of the two powered rotors 19 and 20. In the level flight stage, the fixed-wing aircraft can use the speed difference between the powered rotors 19 and 20 to achieve horizontal steering or rolling, and use the tilting torque of the powered rotors 19 and 20 to achieve pitch adjustment. In addition, the positive and negative tilting torques of the two powered rotors 19 and 20 can also be used to achieve roll adjustment. In the transition phase between vertical and horizontal flight, the fixed-wing aircraft can utilize the coordinated tilting torque of the power rotors 19 and 20 to achieve the tilting of the aircraft, thereby achieving a gradual transition between the vertical and horizontal flight states.

[0092] The above is only an embodiment of the present application and is not intended to limit the protection scope of the present application. Any modifications, equivalent substitutions and improvements made within the spirit and scope of the present application are included in the protection scope of the present application.

Claims

1. A non-rotationally symmetrical propeller, characterized in that: The structure of the propeller has non-rotational symmetry relative to the rotation center, the propeller's several blades include at least one variable thrust blade, the thrust torque generated by the variable thrust blade relative to the rotation center of the propeller is not equal to the thrust torque generated by other blades, and the propeller is used to generate a controllable tilt torque; the propeller is equivalent to a combination of a rotationally symmetrical propeller and a single-blade propeller, the tilt torque of the propeller is only generated by the single-blade propeller, and the propeller also includes a flat thrust blade; at least one of the shape parameters of the variable thrust blade is different from that of the flat thrust blade, and the shape parameters include the three-dimensional shape and geometric parameters of the blade, and the geometric parameters include length, width, thickness and blade angle.

2. The non-rotationally symmetrical propeller according to claim 1, characterized in that: The variable thrust blades include thrust-increasing blades and thrust-reducing blades. The thrust torque generated by the thrust-increasing blades is greater than that of other blades, while the thrust torque generated by the thrust-reducing blades is less than that of other blades.

3. The non-rotationally symmetrical propeller according to claim 2, characterized in that: The propeller is a two-blade propeller, which is equivalent to a rotationally symmetrical two-blade propeller and a single-blade propeller; the thrust f of the equivalent single-blade propeller is d (ω) and the lever arm l d The calculation formula is: Among them, the thrust of the flat-thrust blade is f0(ω), and the lever arm relative to the rotation center of the propeller is l0. The variable-thrust blade is located at an angle θ1, and its thrust is f1(ω). The lever arm relative to the rotation center of the propeller is l1, and the angle of the equivalent single-blade propeller is θ1.

4. The non-rotationally symmetrical propeller according to claim 2, characterized in that: The propeller is a multi-blade propeller including a flat-thrust blade and a variable-thrust blade, which is equivalent to a rotationally symmetrical full-flat-thrust blade propeller and a single-blade propeller; the angle θ of the equivalent single-blade propeller d The calculation formula is: Equivalent single-blade propeller thrust f d (ω) and the lever arm l d The calculation formula is: Where N is the total number of propeller blades, and the nth blade is located at an angle θ n , whose thrust is f n (ω), the moment arm relative to the propeller's rotation center is l n The thrust of the propeller blade is f0(ω), and the moment arm relative to the rotation center of the propeller is l0.

5. A powered rotor, comprising a non-rotationally symmetrical propeller and a motor as described in claims 1 to 4, wherein the propeller is mounted on a rotating shaft of the motor; if the motor drives the propeller in a centrosymmetric speed distribution, the rotor does not generate a tilting torque relative to the rotation center of the propeller; if the motor drives the propeller in a non-centrosymmetric speed distribution, the rotor generates a non-zero tilting torque relative to the rotation center of the propeller; the motor performs vector adjustment on the tilting torque by adjusting the angular distribution of the speed; The tilting moment M t The calculation formula is: in, The angle is determined by the following equation: 0=∮f d (ω(θ))cos(θ t -θ)dθ, Among them, θ t is the angle of the tilt torque synthesized by the equivalent single-blade propeller relative to the x-axis in the rotation plane, ω(θ) is the angular distribution function of the motor angular velocity; wherein the angular distribution function of the motor angular velocity is a positive-valued periodic function, and the periodic function includes a sine function, a cosine function, a triangular wave, a trapezoidal wave, a square wave or a linear combination thereof.

6. The power rotor according to claim 5, characterized in that: The motor drives the propeller to rotate at a non-uniform speed at a specific angle in a non-center-symmetrical speed distribution mode, including an acceleration mode, a deceleration mode and / or a complementary driving mode of acceleration and deceleration.

7. The power rotor according to claim 6, characterized in that: The angular velocity distribution function in the complementary driving mode is: ω(θ)=ω0(1+βsin(θ) M -θ))0≤β<1) Among them, ω0 is the average angular velocity of one rotation, β is the modulation degree of the angular distribution function of the angular velocity, which represents the degree of modulation, and θ M Represents a specific angle, and θ is the azimuth angle of the single-blade propeller.

8. The power rotor according to any one of claims 5 to 7, characterized in that: The power rotor also includes a feedback control system, which obtains the angular position and angular velocity of the motor rotor through a sensor, and controls the motor drive circuit or inverter circuit to generate corresponding multi-phase current, thereby adjusting the speed of the motor at any angular position, so that the power rotor obtains a controllable tilt torque.

9. The power rotor according to any one of claims 5 to 7, characterized in that: If the motor is connected to the mounting base through a universal joint, the power rotor can tilt at any angle in the rotation plane; if the motor is fixed to the base through a tilt axis, the power rotor can tilt in one direction; if two power rotors are fixedly connected to a common tilt axis, the two tilt rotors can achieve synchronous unidirectional tilt.

10. A twin-rotor aircraft, comprising two power rotors as claimed in claims 5 to 9, wherein the power rotors are arranged front and back in the flight direction, and the flight attitude is controlled by adjusting the thrust and tilt torque of the power rotors.

11. A fixed-wing aircraft, comprising a plurality of powered rotors as claimed in claims 5 to 9, wherein the powered rotors are installed symmetrically in the aircraft in the transverse direction and can achieve conversion and control of vertical and horizontal flight attitudes by adjusting the thrust and tilt torque of the powered rotors.

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