CN117360772B

CN117360772B - Vertical take-off and landing aircraft and control method

Info

Publication number: CN117360772B
Application number: CN202311670924.8A
Authority: CN
Inventors: 沙永祥; 薛松柏; 谢晒明; 许兆华; 骆俊昌; 贺鹏; 周文杰
Original assignee: Sichuan Wofei Changkong Technology Development Co ltd; Zhejiang Geely Holding Group Co Ltd
Current assignee: Sichuan Wofei Changkong Technology Development Co ltd; Zhejiang Geely Holding Group Co Ltd
Priority date: 2023-12-07
Filing date: 2023-12-07
Publication date: 2024-02-06
Anticipated expiration: 2043-12-07
Also published as: CN117360772A

Abstract

The invention provides a vertical take-off and landing aircraft and a control method, wherein the aircraft comprises: fuselage, 2N rotor and 2N fixed rotor that tilt. An elevating rudder is arranged on the tail wing; the 2N tilting rotors are symmetrically arranged on two sides of the fuselage, and at least the tilting rotors on the tail wing are full tilting rotors; 2N fixed rotors are positioned outside the tilting rotor; wherein N is a natural number greater than or equal to 2, in a vertical lifting state, 2N fixed rotors are centrally symmetrical about the point A, 2N tilting rotors are centrally symmetrical about the point B, and the point B, the point A and the gravity center G of the whole machine are all positioned in a symmetrical plane of the machine body; and the G point is positioned at one side of the A point close to the nose or coincides with the A point, and the B point is always positioned at one side of the A point close to the tail wing. The vertical take-off and landing aircraft can solve the problems that in the existing vertical take-off and landing aircraft, airflow interference between the tail wing tilt-up rotor wing and the tail wing is large, and pitching control is difficult to carry out.

Description

Vertical take-off and landing aircraft and control method

Technical Field

The invention relates to the technical field of aircrafts, in particular to a vertical take-off and landing aircraft and a control method.

Background

The vertical take-off and landing fixed wing aircraft (distributed propulsion type) not only has the vertical take-off and landing capability of a helicopter, but also has the horizontal efficient and high-speed flight capability of the fixed wing, is quieter, comfortable and economical compared with the helicopter, is more efficient and longer in voyage compared with a plurality of rotor wings, can take off and land vertically on a take-off and landing platform in a city compared with the fixed wing, and is an excellent choice for urban aerial travel. However, in the existing vertical take-off and landing aircraft, when a rotor wing is arranged on a tail wing, air flow generated by the rotor wing and air flow generated by the tail wing are mutually interfered, so that pitch control is easy to be difficult, and unpredictable technical difficulty is brought to flight control of the vertical take-off and landing aircraft.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention provides a vertical take-off and landing aircraft and a control method thereof, so as to solve the problems that in the existing vertical take-off and landing aircraft, airflow interference between a tail wing tilt-up rotor wing and a tail wing is large, and pitch control is difficult to carry out.

To achieve the above and other related objects, the present invention provides a vertical takeoff and landing aircraft comprising: fuselage, 2N rotor and 2N fixed rotor that tilt. Wings are arranged on two sides of the fuselage, a tail fin is arranged at the tail part of the fuselage, and an elevator is arranged on the tail fin; 2N tilting rotors are symmetrically arranged on two sides of the fuselage, part of the 2N tilting rotors are positioned on the tail wing, and at least the tilting rotors positioned on the tail wing are full tilting rotors; the 2N fixed rotors are symmetrically arranged on the wings on two sides of the fuselage and are positioned on the outer sides of the tilting rotors; wherein N is a natural number greater than or equal to 2, in a vertical take-off and landing state, projections of 2N fixed rotors on a horizontal plane are centrosymmetric about a point a, projections of 2N tilting rotors on the horizontal plane are centrosymmetric about a point B, and the point B, the point a and a gravity center G of a vertical take-off and landing aircraft are all located in a symmetrical plane of the fuselage; in the process of transition from the vertical take-off and landing state to the cruising state of the vertical take-off and landing aircraft, the point G and the point B both move along the symmetrical surface towards one side close to the nose, the point G is positioned at one side close to the nose or coincides with the point A, and the point B is always positioned at one side close to the tail wing of the point A.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, the vertical takeoff and landing aircraft includes four tilting rotors and four fixed rotors, and the distance from the center of gravity G point to the point a is L1, L1 is greater than or equal to 0, the distance from the point a to the point B is L2, L2 is greater than 0, the distance between the four fixed rotors along the extending direction of the fuselage is L3, and the distance between the four tilting rotors along the extending direction of the fuselage is L4, wherein 0.1 (l3+l4) is greater than or equal to 4l1+2l2 is greater than or equal to 0.01 (l3+l4).

In an embodiment of the vertical take-off and landing aircraft, the tail wing is a V-shaped tail wing, two tilt rotors are mounted on the V-shaped tail wing, the two tilt rotors are mounted at wing tips of the V-shaped tail wing respectively, in a vertical take-off and landing state, the distance between the rotation center of the tilt rotor on the tail wing and the front edge of the wing tip of the V-shaped tail wing is t1, and the chord length of the wing tip of the V-shaped tail wing is t2, wherein the ratio of t1 to t2 is 15% -40%.

In an embodiment of the vertical takeoff and landing aircraft, the rotation axis of the vertical takeoff and landing aircraft is defined as 0 DEG, the tilting rotor is tilted upwards to be positive, the downward tilting is tilted downwards to be negative, and the rotation axis of the tilting rotor is tilted within a range of-20 DEG to 110 deg.

In one embodiment of the vertical takeoff and landing aircraft of the present invention, the full tilt rotor includes a first rotor coupled to the power pod and a power pod rotatably coupled to the tail wing, the power pod being synchronously tilted with the first rotor during tilting of the first rotor.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, a fairing is provided in the center of the first rotor, and a projection of the fairing covers a projection of the nacelle along a direction in which a rotation axis of the first rotor extends.

In an embodiment of the vertical take-off and landing aircraft, the power nacelle is a revolving body structure, and a revolving shaft of the revolving body structure and a revolving shaft of the first rotor wing are coaxially arranged; the surface of the power pod is in streamline arrangement.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, the first rotor includes a propeller and a rotation driving device, the propeller is mounted on an output shaft of the rotation driving device, the power pod includes a pod housing and a tilting mechanism located in the pod housing, and the tilting mechanism is used for driving the rotation driving device to tilt so as to drive the propeller to tilt.

In one embodiment of the vertical takeoff and landing aircraft of the present invention, the tilting mechanism includes:

the rocker arm is rotatably arranged on the tail wing and fixedly connected with the rotary driving device;

the driving arm is rotatably arranged on the tail wing, and the rotating shaft is parallel to the rotating shaft of the rocker arm;

the seat body of the tilting driving device is arranged on the tail wing, and the driving end of the tilting driving device drives the driving arm to rotate;

and the connecting rod is respectively connected with the driving arm and the rocker arm in a rotating way.

In an embodiment of the vertical take-off and landing aircraft, a first shaft body and a second shaft body which are parallel to each other are fixedly arranged on the tail wing, the rocker arm is rotatably mounted on the first shaft body, the driving arm is rotatably mounted on the second shaft body, a seat body of the tilting driving device is mounted on the first shaft body, and the seat body of the tilting driving device is fixedly connected with a shell of the tilting driving device; the driving end of the tilting driving device is coaxial with the second shaft body and fixed with the driving arm.

In an embodiment of the vertical take-off and landing aircraft of the present invention, the elevator includes a rudder plate rotatably connected to the tail of the tail wing or the fuselage, and a rudder body driving device for driving the rudder plate to rotate so as to adjust the direction of the vertical take-off and landing aircraft.

In an embodiment of the vertical take-off and landing aircraft, a ratio of a chord length of the rudder plate to a chord length of the tail wing is 15% -100%.

In an embodiment of the vertical take-off and landing aircraft, the initial position parallel to the tail wing is 0 degrees, the upward deflection is positive, the downward deflection is negative, and the deflection angle of the rudder plate is-90 degrees to 30 degrees.

In one embodiment of the vertical take-off and landing aircraft, the included angles between the rotation axes of 2N fixed rotor wings and the symmetrical plane of the aircraft body are-15 degrees to +15 degrees;

and/or, the included angle alpha between the plane formed by the rotation axis of the tilting rotor in the tilting process and the symmetrical plane of the machine body is-15 degrees to +15 degrees.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, the tail wing is any one of a V-shaped tail wing, a Y-shaped tail wing, an X-shaped tail wing, a T-shaped tail wing, an H-shaped tail wing, or a U-shaped tail wing, wherein a part of the tilt rotor is mounted on the tail wing.

In an embodiment of the vertical take-off and landing aircraft of the present invention, the wing on both sides of the fuselage is provided with an organic arm, and the 2N fixed rotors are symmetrically installed on the organic arms on both sides of the fuselage and are respectively located on the front and rear sides of the wing.

In one embodiment of the vertical takeoff and landing aircraft of the present invention, pitch control is performed using the following method:

during the flying process, distributing the pitch control proportion of the elevator to 2N tilt rotors and 2N fixed rotors according to the current airspeed or dynamic pressure;

and respectively controlling the elevator, the 2N tilting rotors and the 2N fixed rotors according to the pitching control proportion so as to realize pitching balancing and operation.

In one embodiment of the vertical takeoff and landing aircraft of the present invention, controlling 2N of said tiltrotors according to said pitch control ratio includes:

differentially adjusting the pitching moment to perform pitching balancing and manipulation through the tilting angle difference between the tilting rotor on the tail wing and any other tilting rotor;

and/or differentially adjusting the pitching moment to pitch trim and maneuver through the rotational speed differential of the tiltrotor on the tail with any of the other tiltrotors;

and/or differentially adjusting the pitching moment to pitch trim and maneuver through the difference in pitch speed of the tiltrotor on the tail and any of the other tiltrotors.

The invention also provides a control method of any vertical take-off and landing aircraft, which comprises the following pitching control process:

Distributing the pitch control proportion of the elevator to 2N tilt rotors and 2N fixed rotors according to the current airspeed or dynamic pressure;

In an embodiment of the control method of the present invention, before distributing the pitch control ratio of the elevator to 2N of the tiltrotors and 2N of the fixed rotors according to the current airspeed or dynamic pressure, the control method further includes the following rotor control procedure:

acquiring the current tilting position of each tilting rotor;

if the current tilting position is inconsistent with the set cruising position, acquiring the current airspeed or dynamic pressure of the corresponding tilting rotor under the current tilting position, and judging whether the current airspeed or dynamic pressure is equal to or greater than a preset threshold under the current tilting position;

if the current airspeed or dynamic pressure is equal to or greater than a preset threshold value at the current tilting position, controlling the tilting rotor to tilt to a preset next position;

the rotational speed of 2N tilting rotors is gradually increased, and the rotational speed of 2N fixed rotors is gradually reduced to the set rotational speed.

In one embodiment of the control method of the present invention, the following take-off control process is further included before the rotor control process:

Tilting 2N of said tiltrotors to an axis of rotation vertically or obliquely upward;

deflecting the lifting rudder downwards;

and starting 2N fixed rotors and 2N tilting rotors, and sending out a flat flight instruction when the vertical take-off and landing aircraft reaches a set height.

In an embodiment of the control method of the present invention, the following take-off process is further included before the pitch control process:

tilting 2N of said tiltrotors to an axis of rotation horizontally forward;

deflecting the lifting rudder downwards;

In an embodiment of the control method of the present invention, during the rotor control process, after the take-off control process, before the pitch control process, the following rotor control process is further included: the rotational speed of 2N tilting rotors is gradually increased, and the rotational speed of 2N fixed rotors is gradually reduced to the set rotational speed.

In an embodiment of the control method of the present invention, in the rotor control process, after gradually reducing the rotational speeds of the 2N fixed rotors to the set rotational speed, the method further includes controlling the elevator to return to zero or to a trim rudder deflection value matched with the current airspeed/dynamic pressure according to the current airspeed or dynamic pressure, and gradually participating in the pitch control process.

In one embodiment of the control method of the present invention, the rotor control process and the pitch control process are sequentially and repeatedly executed until the tilt rotor tilts to the cruising position, thereby completing the take-off and leveling-off.

According to the vertical take-off and landing aircraft, 2N tilting rotors are arranged on the inner sides of 2N fixed rotors, and the elevating rudders and the tilting rotors which are fully tilted are arranged on the tail wing, so that on one hand, the power nacelle rotates along with the rotors in the tilting process of the tilting rotors on the tail wing, and when hovering, the shielding area of the power nacelle in the corresponding rotors is smaller, so that the area of the lower wash stream of the rotors on the tail wing is smaller, a part of head-up moment can be reduced, the control of the pitching moment of the vertical take-off and landing aircraft under a complex interference flow field can be improved, and on the other hand, the pitching balancing and the operation can be further carried out through coordination of the fixed rotors, the tilting rotors and the elevating rudders.

Further, in the layout of the vertical take-off and landing aircraft, the center of gravity of the vertical take-off and landing aircraft is not coincident with the center of symmetry of the fixed rotor wing or the center of symmetry of the tilting rotor wing, and in the process that the vertical take-off and landing aircraft transits from the vertical take-off and landing state to the cruising state, the point G and the point B both move along the symmetrical surface towards one side close to the nose, the point G is positioned at one side close to the nose or coincides with the point A, the point B is always positioned at one side close to the tail wing, so that the moment of the traction force generated by the front-center tilting rotor wing and the fixed rotor wing to the center of gravity G is smaller, the moment of the traction force generated by the rear-center tilting rotor wing and the fixed rotor wing to the center of gravity G is larger, and the moment difference of the front-rear rotor wings can resist the part of lifting moment generated by the action of the tilting rotor wing washing area to the tail wing, so that the difficulty of pitching operation can be reduced. Therefore, under the condition that the rotary wings or the tilting rotary wings are fixed on the front side and the rear side of the gravity center G point at the same rotating speed of the throttle, because the length difference of the moment arm on the gravity center G point can generate low head moment, the head lifting moment generated by the action of the tilting rotary wing washing area on the tail wing can be counteracted or partially counteracted by the low head moment, so that the vertical take-off and landing aircraft can better trim the pitching moment under the condition that the throttle of the front and rear rotary wings is consistent.

Further, in the tilting stage of the tilting rotor, because of aerodynamic interference, the vertical take-off and landing aircraft also generates an additional larger head-up moment, and in the tilting process of the tilting rotor, the center of gravity of the vertical take-off and landing aircraft gradually moves towards the nose along with the tilting process, and the point B of the symmetry center of the tilting rotor gradually moves towards the nose, and because the point G of the center of gravity is always in front of the point B, the moment difference between the tilting rotor on the front side of the point G of the center of gravity and the tilting rotor behind the point G of the center of gravity in the whole tilting stage can also generate a part of low head-up moment so as to offset or partially offset the head-up moment caused by the aerodynamic interference.

Further, in the tilting stage and the cruising stage, the gravity center G point is close to the front side relative to the point A and the point B, so that the aircraft has relatively large longitudinal and course static stability margin, has stronger capability of resisting extremely strong windy weather, and is safer in flight.

Further, for the manned vertical take-off and landing aircraft, the arranged manned seats are arranged on the front fuselage, so that the weight of passengers and baggage is relatively forward, the layout mode of the vertical take-off and landing aircraft is extremely friendly to the counterweight of the aircraft, and when passengers with different numbers of passengers are taken, the permitted variation range of the gravity center is relatively wide, so that the aircraft flight safety is facilitated.

According to the control method, the elevator, the pitch control proportion of 2N tilting rotors and 2N fixed rotors is distributed according to the current airspeed or dynamic pressure, and the pitch control can be realized through linkage of the elevator, the 2N tilting rotors and the 2N fixed rotors.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is an isometric view of an embodiment of a vertical takeoff and landing aircraft according to the present invention at cruise conditions;

FIG. 2 is an isometric view of a vertical takeoff and landing aircraft according to an embodiment of the present invention in a vertical takeoff and landing state;

FIG. 3 is a top view of an embodiment of a vertical takeoff and landing aircraft according to the present invention in a vertical takeoff and landing state;

FIG. 4 is a side view of an embodiment of a vertical takeoff and landing aircraft according to the present invention in a vertical takeoff and landing state;

FIG. 5 is a rear view of an embodiment of a vertical takeoff and landing aircraft according to the present invention in a vertical takeoff and landing state;

FIG. 6 is a partial view of a full tilt rotor;

FIG. 7 is a partial view of the full tiltrotor after removal of the nacelle housing;

FIG. 8 is a top view of the full tiltrotor with the nacelle housing removed;

FIG. 9 is a cross-sectional view of D-D of FIG. 8;

FIG. 10 is another view of the tilt rotor after removal of the nacelle housing;

FIG. 11 is a three-dimensional view of the full tiltrotor with the nacelle housing removed in another orientation;

FIG. 12 is a cross-sectional F-F view of FIG. 10;

FIG. 13 is a P-P cross-sectional view of FIG. 10;

FIG. 14 is a partial view of the full tilt rotor in a cocked state with a rudder plate chord length of 30%;

FIG. 15 is a partial view of the full tilt rotor in a flapped condition with a rudder plate chord length of 60%;

FIG. 16 is a partial view of the full tilt rotor in the flapped state with the rudder plate chord length at 100%;

FIG. 17 is a partial view of the full tilt rotor in cruise condition;

FIG. 18 is a partial view of the full tilt rotor in a climb-up condition;

FIG. 19 is a rotational path diagram of the elevator rudder;

FIG. 20 is a top view of the tail wing in a vertical take-off and landing condition;

FIG. 21 is a schematic diagram of the chord length ratio of the rudder plate of the tail wing and the deflection angle of the rudder plate;

FIG. 22 is a partial pitch schematic of a tail pitch rotor power nacelle;

FIG. 23 is a graph showing the variation of pitching moment (dimensionless) of the whole machine with wind speed (dimensionless) according to the nacelle partial tilting and full tilting control method (CFD simulation result);

FIG. 24 is a flow chart of an embodiment of the vertical takeoff and landing aircraft of the present invention from a ground state to a cruise state;

FIG. 25 is a flow chart of a take-off and landing aircraft of an embodiment of the present invention;

FIG. 26 is a flow chart of pitch control for one embodiment of a vertical takeoff and landing aircraft of the present invention;

FIG. 27 is a flow chart of rotor control for an embodiment of a vertical takeoff and landing aircraft according to the present invention;

FIG. 28 is a flow chart of a takeoff control process for an embodiment of a vertical takeoff and landing aircraft according to the present invention;

FIG. 29 is a flow chart of a takeoff control process for an embodiment of a vertical takeoff and landing aircraft according to the present invention;

fig. 30 is a top view of an embodiment of a vertical takeoff and landing aircraft according to the present invention in a vertical takeoff and landing position.

Description of element reference numerals

10. A body; 20. a wing; 30. a tail wing; 31. an elevator; 311. a rudder plate; 41. a first tilt rotor; 411. a third horn; 42. a second tilt rotor; 421. a fourth horn; 43. a third tilt rotor; 432. a first power pod; 44. a fourth tilt rotor; 441. a first rotor; 4411. a propeller; 4412. a rotation driving device; 4413. a fairing; 442. a second power pod; 4421. tilting drive means; 4422. a rocker arm; 4423. a first shaft body; 4424. a second shaft body; 4425. a holding structure; 4426. a connecting rod; 4427. a first hinge shaft; 4428. a second hinge shaft; 4429. a driving arm; 4430. a bearing; 4431. a pod housing; 4432. a mating surface; 51. a first stationary rotor; 511. a first horn; 52. a second stationary rotor; 521. a second horn; 53. a third stationary rotor; 54. a fourth stationary rotor; 60. a plane of symmetry; 101. a first curve; 102. a second curve.

Description of the embodiments

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. It is also to be understood that the terminology used in the examples of the invention is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the invention. The test methods in the following examples, in which specific conditions are not noted, are generally conducted under conventional conditions or under conditions recommended by the respective manufacturers.

Where numerical ranges are provided in the examples, it is understood that unless otherwise stated herein, both endpoints of each numerical range and any number between the two endpoints are significant both in the numerical range. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs and to which this invention belongs, and any method, apparatus, or material of the prior art similar or equivalent to the methods, apparatus, or materials described in the examples of this invention may be used to practice the invention.

It should be understood that the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like are used in this specification for descriptive purposes only and not for purposes of limitation, and that the invention may be practiced without materially departing from the novel teachings and without departing from the scope of the invention.

For ease of distinction, we first describe the concepts of "full tiltrotor" and "partial tiltrotor" as follows. The existing tilting rotor comprises a rotor and a power nacelle, wherein a motor and control components can be installed in the power nacelle. The "partial tilt rotor" cuts off the nacelle, and during tilting of the rotor, the part close to the rotor tilts together with the rotor, and the part far away from the rotor is fixed relative to the fuselage 10. In the "full tilt rotor", the entire nacelle tilts with the corresponding rotor. Considering the complexity of the airflow field in the flight process and the flight safety, how to arrange the tilting rotor and the fixed rotor to optimize the airflow anti-interference capability and the flight stability of the vertical take-off and landing aircraft has great challenges.

In view of the above problems, referring to fig. 1 to 29, the present invention provides a vertical take-off and landing aircraft and a control method thereof, in which 2N tilt rotors are disposed inside 2N fixed rotors, and an elevator 31 and a full-tilt rotor are disposed on a tail wing 30, so that pitch balancing and manipulation can be performed by coordination of the fixed rotors, the tilt rotors and the elevator 31, and the control problem caused by air flow interference between the tilt rotor and the tail wing 30 on the tail wing 30 in the conventional vertical take-off and landing aircraft can be improved.

Referring to fig. 1 to 21, the present invention provides a vertical takeoff and landing aircraft, comprising: fuselage 10, 2N tiltrotors, and 2N stationary rotors. The fuselage 10 is of a symmetrical structure, and has a symmetry plane 60 (i.e., a vertical plane in which the straight line O1-O2 is located in fig. 3) extending along the length direction of the fuselage 10, and the rest of the fuselage 10 is not limited in structure and shape, and can refer to the fuselage 10 structure of the existing vertical take-off and landing aircraft, and the fuselage 10 includes conventional operation systems of the aircraft, such as an avionics system, an flight control system, an electrical system, and a navigation system, which are not described herein. The wings 20 are disposed on two sides of the fuselage 10, the wings 20 on two sides are symmetrical with respect to the symmetry plane 60 of the fuselage 10, and the structure of the wings 20 can also refer to the fixed wing structure of the existing aircraft, which is not described herein. The tail part of the fuselage 10 is provided with a tail wing 30, and the tail wing 30 is integrally formed with or mechanically connected with the fuselage 10 and symmetrically arranged relative to a symmetry plane 60 of the fuselage 10. The tail wing 30 is provided with an elevator 31, and the installation position and structure of the elevator 31 may be various, for example, may be disposed at any suitable position on the tail wing 30, or may be any suitable elevator structure.

Critically, referring to fig. 1 to 5,2N, the tiltrotors are mounted on both sides of the fuselage 10, wherein N is a natural number greater than or equal to 2, 2N tiltrotors are symmetrically disposed about the plane of symmetry 60 of the fuselage 10, a portion of 2N tiltrotors are mounted on the tail wing 30, and at least the tiltrotors on the tail wing 30 are all tiltrotors. The specific structure of the full-tilt rotor and the specific position of the rotor mounted on the tail wing 30 are not limited, and the rotor is symmetrical about the symmetry plane 60 of the fuselage 10, and the power nacelle corresponding to the rotor may tilt together with the rotor during the tilting process. The remaining tiltrotors are mounted on the fuselage 10 and/or the wing 20, and the tiltrotors on the fuselage 10 and/or the wing 20 are also symmetrical about the plane of symmetry 60 of the fuselage 10. It should be noted that, if the installation condition allows, all of the 2N tiltrotors may be full tiltrotors, but considering that the existing tiltrotors on the fuselage 10 or the wing 20 on the front side of the tail wing 30 are mostly installed on the horn, in this embodiment, the tiltrotors on the tail wing 30 are full tiltrotors, and the tiltrotors on the fuselage 10 or the wing 20 on the front side of the tail wing 30 are partial tiltrotors. The particular location and manner of mounting of portions of the tiltrotor on the wing 20 or fuselage 10 may be without limitation. For example, may be mounted directly to the wing 20 or may be mounted to the wing 20 or fuselage 10 via arms.

Referring to fig. 1 to 5,2N, the fixed rotors are symmetrically installed at both sides of the fuselage 10, and 2N fixed rotors are positioned at the outer sides of 2N of the tilt rotors and are symmetrical with respect to the symmetry plane 60 of the fuselage 10. The structure of the 2N fixed rotors can be referred to all the suitable fixed rotor forms, the specific position of the 2N fixed rotors mounted on the fuselage 10 and/or the wing 20 can be not limited, for example, the fixed rotors can be directly mounted on the wing 20, or can be mounted on the wing 20 or the fuselage 10 through support arms, it should be noted that in the present invention, the fixed rotors are located on the outer sides of all the tilt rotors, and can be located on the outer sides in any directions, but preferably, in order to optimize the structure and reduce the weight, the 2N fixed rotors in the present embodiment are located on the outer sides of the tilt rotors along the extending direction of the wing 20.

Referring to fig. 30, in the vertical take-off and landing state, the projections of 2N fixed rotors on the horizontal plane are centrosymmetric with respect to the point a, the projections of 2N tilting rotors on the horizontal plane are centrosymmetric with respect to the point B, and the points B, a and the center of gravity G of the vertical take-off and landing aircraft are all located in the symmetry plane 60 of the fuselage 10; in the transition process of the vertical take-off and landing aircraft from the vertical take-off and landing state to the cruise state, the point G and the point B move along the symmetrical surface towards one side close to the aircraft nose, the point G is positioned on one side close to the aircraft nose or coincides with the point A, the point B is always positioned on one side close to the tail wing 30 of the point A, namely the distance from the center of gravity G to the point A is L1, L1 is more than or equal to 0, and the distance from the point A to the point B is L2, and L2 is more than 0. Specifically, the nose of the vertical take-off and landing aircraft is used for forward, the center B point of the 2N tilting rotors is positioned at the rear side of the center A point of the 2N fixed rotors, the distance L2 from the A point to the B point is more than 0, as the 2N tilting rotors tilt forward, the gravity center of the 2N tilting rotors, the gravity center G of the vertical take-off and landing aircraft and the symmetrical center B point move towards the direction close to the nose, and the whole tilting process from the preset vertical take-off and landing position (for example, 90-degree tilting angle) of the 2N tilting rotors to the preset cruising position (for example, 0-degree tilting angle) is started, and always L2 is more than 0; meanwhile, the gravity center G of the vertical take-off and landing aircraft is positioned on the front side of the symmetry center B of the 2N tilting rotors and is also positioned on the front side of the symmetry center A of the 2N fixed rotors or coincides with the A point, namely the distance L1 from the A point to the G point is more than or equal to 0, and the gravity center G gradually moves forwards along with forward tilting of the 2N tilting rotors, and the absolute value of L1 is also larger and larger.

In the layout mode, the gravity center of the vertical take-off and landing aircraft is not coincident with the symmetry center of the fixed rotor wing or the symmetry center of the tilting rotor wing, in the process of transition from the vertical take-off and landing state to the cruising state of the vertical take-off and landing aircraft, the point G and the point B move along the symmetry plane towards one side close to the nose, the point G is positioned at one side close to the nose or coincides with the point A, the point B is always positioned at one side close to the tail wing 30, so that the moment of the traction force generated by the front-side tilt rotor wing and the fixed rotor wing on the gravity center G is smaller, the moment of the traction force generated by the rear-side tilt rotor wing and the fixed rotor wing on the gravity center G is larger, and the moment difference of the front-back rotor wing can resist the partial head-lifting moment generated by the action of the tilting rotor wing wash area on the tail wing 30, so that the difficulty of pitching operation can be reduced. Therefore, under the condition that the rotary wings or the tilting rotary wings are fixed on the front side and the rear side of the gravity center G point at the same rotating speed of the throttle, because the length difference of the moment arm on the gravity center G point can generate low head moment, the head lifting moment generated by the action of the tilting rotary wing washing area on the tail wing 30 can be counteracted or partially counteracted by the low head moment, so that the vertical take-off and landing aircraft can better balance the pitching moment under the condition that the front and rear rotary wing throttle is consistent.

The number of the tilting rotors on the tail wing 30 may be any even number less than 2N, preferably, referring to fig. 1 to 5, in this embodiment, the vertical takeoff and landing aircraft includes four tilting rotors and four fixed rotors, four of the fixed rotors are symmetrically installed on two sides of the fuselage 10, four of the tilting rotors are located on the spanwise inner sides of four of the fixed rotors, two of the tilting rotors are installed on the tail wing 30, and two of the tilting rotors are installed on the fuselage 10 or the wing 20 on the front side of the wing 20. Specifically, the four tiltrotors are divided into two equal sets, labeled as a first set of tiltrotors mounted on the fuselage 10 or wing 20 on the front side of the center of gravity G of the vertical takeoff and landing aircraft, and a second set of tiltrotors mounted on the tail wing 30 on the rear side of the center of gravity G of the vertical takeoff and landing aircraft, respectively. The first set of tilt rotors includes a first tilt rotor 41 and a second tilt rotor 42, and the second set of tilt rotors includes a third tilt rotor 43 and a fourth tilt rotor 44. First tiltrotor 41 is mounted on third horn 411, and second tiltrotor 42 is mounted on fourth horn 421 and is symmetrical to first tiltrotor 41 about plane of symmetry 60 of fuselage 10. Third tiltrotor 43 is mounted to tail 30 via first nacelle 432, and fourth tiltrotor 44 is mounted to tail 30 via second nacelle 442. The first power pod 432 and the second power pod 442 are symmetrically disposed about the plane of symmetry 60 of the fuselage 10 and the fourth tiltrotor 44 and the third tiltrotor 43 are symmetrically disposed about the plane of symmetry 60 of the fuselage 10.

In the vertical take-off and landing state, the rotation shafts of the four tilting rotors tilt upward in the vertical direction, and the first tilting rotor 41, the second tilting rotor 42, the third tilting rotor 43 and the fourth tilting rotor 44 are all distributed on a first circumference centered on the point B. The projections of the first tilt rotor 41 and the fourth tilt rotor 44 on the horizontal plane are centered with respect to the point B, and the projections of the second tilt rotor 42 and the third tilt rotor 43 on the horizontal plane are centered with respect to the point B.

The four fixed rotors are divided into two groups of equal numbers, and are respectively marked as a first group of fixed rotors and a second group of fixed rotors, wherein the first group of fixed rotors are installed on the wing 20 on the front side of the center of gravity of the vertical take-off and landing aircraft, and the second group of fixed rotors are installed on the wing 20 on the rear side of the center of gravity of the vertical take-off and landing aircraft. The first fixed rotor wings are composed of a first fixed rotor wing 51 and a second fixed rotor wing 52, the second fixed rotor wings are composed of a third fixed rotor wing 53 and a fourth fixed rotor wing 54, and the first fixed rotor wings 51, the second fixed rotor wings 52, the third fixed rotor wings 53 and the fourth fixed rotor wings 54 are distributed on a second circumference taking the point A as the center. The first fixed rotor 51 and the second fixed rotor 52 are symmetrical about the symmetry plane 60 of the fuselage 10, the third fixed rotor 53 and the fourth fixed rotor 54 are symmetrical about the symmetry plane 60 of the fuselage 10, the rotation axes of the four fixed rotors all extend upwards, the projections of the first fixed rotor 51 and the fourth fixed rotor 54 on the horizontal plane are central symmetrical about the point a, and the projections of the second fixed rotor 52 and the third fixed rotor 53 on the horizontal plane are central symmetrical about the point a. In the present application, the front side means the extending direction toward the nose, and the rear side means the extending direction toward the tail 30.

Referring to fig. 3, in an embodiment of the vertical takeoff and landing aircraft of the present invention, the pitch of four fixed rotors along the extending direction of the fuselage, that is, the pitch of the second fixed rotor 52 to the fourth fixed rotor 54 or the pitch of the first fixed rotor 51 to the third fixed rotor 53 is L3. The pitch of the four tiltrotors along the extending direction of the fuselage, that is, the pitch of the second tiltrotor 42 to the fourth tiltrotor 44 or the pitch of the first tiltrotor 41 to the third tiltrotor 43 is L4, is 0.1 (l3+l4) > 4l1+2l2 > 0.01 (l3+l4). The arrangement mode can enable the gravity center G point to be close to the front side relative to the point A and the point B in the tilting stage and the cruising stage, so that the aircraft has relatively large longitudinal and course static stability margin, has stronger capability of resisting extremely strong wind weather, and is safer in flight.

According to the vertical take-off and landing aircraft, 2N tilting rotors are arranged on the inner sides of 2N fixed rotors, and the elevating rudders 31 and the full-tilting rotors are arranged on the tail wing 30, so that on one hand, the power nacelle on the tail wing 30 rotates along with the rotors in the tilting process, and in a hovering state, the shielding area of the power nacelle in the corresponding rotor is smaller, so that the area of the rotor, which is wetted by the downwash, on the tail wing 30 is smaller, a part of head-up moment can be reduced, the control of the pitching moment of the vertical take-off and landing aircraft under a complex interference flow field can be improved, and on the other hand, the pitching balancing and the operation can be further coordinated through the fixed rotors, the tilting rotors and the elevating rudders 31.

Referring to fig. 20, in an embodiment of the vertical takeoff and landing aircraft of the present invention, the tail wing 30 is a V-shaped tail wing, a third tilt rotor 43 is installed on one wing tip of the V-shaped tail wing, a fourth tilt rotor 44 is installed on the other wing tip of the V-shaped tail wing, and the third tilt rotor 43 and the fourth tilt rotor 44 are symmetrical with respect to a symmetry plane 60 of the fuselage 10. In the vertical take-off and landing state, along the direction parallel to the rolling axis X of the aircraft, the distance between the rotation center of the tilt rotor wing of the tail wing 30 and the front edge of the wing tip of the V-shaped tail wing is t1, and the chord length of the wing tip of the V-shaped tail wing is t2, wherein the ratio of t1 to t2 is 15% -40%. According to the structural strength stress analysis of the wing tip of the tail wing 30, the tilting mechanism is connected with the wing tip of the tail wing 30 within the range, the thickness of the tail wing 30 is thicker, and the stress condition of the tail wing 30 is better.

Referring to fig. 1 to 3, and fig. 17 to 19, in an embodiment of the vertical take-off and landing aircraft of the present invention, a tilt angle of 0 ° is defined based on a roll axis X, the roll axis X tilts upward to be positive, the roll axis X tilts downward to be negative, and the rotation axis of the tilt rotor tilts within a range of-20 ° to 110 °. Referring to fig. 17,0 ° is that the rotation axis of the tilting rotor extends forward along the rolling axis X direction; referring to fig. 19, 90 ° is a state in which the rotation axis of the tiltrotor is oriented upward in the vertical direction, and referring to fig. 18, the rotation axis of the tiltrotor is inclined between 0 ° and 90 °. When the tilting angle is 90-110 degrees, the vertical take-off and landing aircraft can realize forward and backward flight of the aircraft nose, so that the flight envelope and capacity of the vertical take-off and landing aircraft are greatly expanded, and the risk that the vertical take-off and landing aircraft needs to turn around in the air is reduced. When the vertical take-off and landing aircraft needs take-off, according to flight control requirements, all tilt angles of the tilt rotors on the inner side can be set at any angle of 0-90 degrees, for example, can be set at 0 degrees, 30 degrees, 45 degrees, 60 degrees or 90 degrees, etc.

In the vertical take-off and landing aircraft, the rotation axes among the tilting wings can be arranged in parallel or not in parallel under various states, such as a cruise state in which the aircraft flies in the horizontal direction, a take-off state in which the aircraft takes off and lands in the vertical direction, and a mode conversion state (comprising conversion from the take-off state to the cruise state and conversion from the cruise state to the take-off state). In one embodiment of the vertical takeoff and landing aircraft of the present invention, during flight, the rotation axis of any one of the tiltrotors on the tail wing 30 and the rotation axis of any one of the other tiltrotors on the plane of symmetry 60 of the fuselage 10 are projected to be non-parallel, and different tiltrotors are provided with moments in different directions through the non-parallel rotation axes, so that the pitching moment of the whole vertical takeoff and landing aircraft is controlled.

In this embodiment, when the vertical takeoff and landing aircraft is in the cruising state, the rotation axis of the tiltrotor on the tail wing 30 and the rotation axis of the tiltrotor at other positions may extend along the roll axis X, but in other embodiments, the rotation axis of the tiltrotor on the tail wing 30 and the rotation axis of the tiltrotor at other positions may not extend along the roll axis X, may be parallel to a vertical plane on which the roll axis X is located, and may be defined as a tilt angle of 0 ° based on being parallel to the roll axis X, and may extend within ±20° with the roll axis X tilting upward to positive, and the roll axis X tilting downward to negative. In addition, in the invention, the tilting rotors positioned at different coordinate positions of the rolling axis X are projected along the rolling axis X, the control of power pods of the tilting rotors can be mutually independent, and the tilting can be independently controlled and not mutually related, in the mode, the tilting angles of the tilting rotors at the front side and the tilting rotors on the tail wing 30 can be inconsistent, the tilting process can be asynchronous, for example, the tilting process can be 0 DEG with the rolling axis X, the rolling axis X is positive, the tilting angle of the power pods of the tilting rotors on the front side fuselage 10 or the wing 20 can be 10 DEG, and the power pod tilting angle of the tilting rotors on the rear side fuselage 10 or the wing 20 or the tail wing 30 can be-10 deg.

It should be noted that, when the vertical takeoff and landing aircraft of the present invention is in the vertical takeoff and landing state, the rotation axis of the tiltrotor on the tail wing 30 and the rotation axis of the tiltrotor at other positions may or may not extend upward in the vertical direction. That is, the tilt angles of the front tilt rotor and the tilt rotor on the tail 30 are not limited to being set at the tilt angle of 90 °, and the tilt angle of the rotation axis of the front tilt rotor and the tilt angle of the rotation axis of the tilt rotor on the tail 30 may be any value between 70 ° to 110 °, for example, 70 °, 80 °, 90 °, 100 °, 110 °, and the like, for the purpose of enhancing the control capability. The rotational control and the tilt control of each of the 2N tilt rotors are relatively independent, and the tilt angles of the 2N tilt rotors may be set to be identical, may be set to be different between any two, may be set to be partially identical, and, for example, may be set to be identical between the tilt angles of the 2N tilt rotors located on the fuselage 10 or wing 20 on the front side of the tail wing 30, may be labeled as a first tilt angle, and the tilt angles of the tilt rotors on the rear side tail wing 30 may be set to be identical, may be labeled as a second tilt angle, and may be set such that the first tilt angle is not equal to the second tilt angle, for example, the first tilt angle may be 100 °, and the second tilt angle may be 80 °. This allows different pitch trim moments to be obtained at different positions. The tilt angle of the tilt rotor is an angle between the rotation axis of the tilt rotor and the aircraft roll axis X with the center point of the tilt axis of the tilt rotor as the apex.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, the full tilt rotor structure may be any existing tilt rotor structure capable of achieving synchronous tilting of the whole power nacelle along with the rotor, referring to fig. 6 and 14, the full tilt rotor comprises a first rotor 441 and a power nacelle, the first rotor 441 is connected to the power nacelle, and the power nacelle is rotatably connected to the tail wing 30 and is synchronously tilted along with the first rotor 441 during tilting of the first rotor 441. The housing of the power pod may contain a power device therein, for example, if in an electric-only configuration, a motor, an electronic control, a ring control, a tilting mechanism, etc.; in the case of the oil-powered configuration, the nacelle contains the engine, ECU, tilting mechanism, etc., and preferably the power nacelle of the present embodiment has a purely electric configuration mounted inside its housing.

Referring to fig. 6, in an embodiment of the vertical takeoff and landing aircraft of the present invention, a fairing 4413 is disposed at the center of the first rotor 441, and the fairing 4413 is mounted on the windward side of the first rotor 441 for reducing air flow resistance, preferably, along the direction in which the rotation axis of the first rotor 441 extends, the projection of the fairing 4413 covers the projection of the power nacelle. This arrangement reduces the effect of the nacelle on the downwash of the rotor during flight. However, it will be appreciated by those skilled in the art that the projection of the nacelle may be partially within the projection of the fairing 4413 and may also function to partially reduce drag, but only to a lesser extent relative to the full coverage of the former.

The power pod has a shape including, but not limited to, a revolution body, a square body, an ellipsoid, etc., preferably, in an embodiment of the vertical take-off and landing aircraft of the present invention, the power pod is a revolution body structure, and a revolution shaft of the revolution body structure is coaxially arranged with a rotation shaft of the first rotor 441; the surface of the power pod is in streamline arrangement. Thus, the influence of the power nacelle on the corresponding rotor wing downwash area in the flying process can be reduced.

Referring to fig. 6 to 14, the first rotor 441 includes a propeller 4411 and a rotation driving device 4412, the propeller 4411 is mounted on an output shaft of the rotation driving device 4412, and the power pod includes a pod housing 4431 and a tilting mechanism within the pod housing 4431 for driving the rotation driving device 4412 to tilt. The tilting mechanism of the present invention may be any suitable tilting mechanism capable of driving the power pod and the rotation driving device 4412 to tilt synchronously, and preferably, in this embodiment, the tilting mechanism includes: a rocker arm 4422, a driving arm 4429, a tilting driving device 4421, and a link 4426. The tilting drive 4421 may be of any suitable type of construction having a rotary output shaft, for example, a steering engine, a combination of steering engine and speed reducer, etc., in which the tilting drive 4421 is a steering engine. The rocker 4422 is rotatably mounted on the tail wing 30, and one end of the rocker 4422, which is close to the rotation driving device 4412, is fixedly connected with the rotation driving device 4412; the driving arm 4429 is rotatably mounted on the tail wing 30, and the rotating shaft is parallel to the rotating shaft of the rocker arm 4422; the base of the tilting driving device 4421 is fixedly arranged on the tail wing 30, and the driving end of the tilting driving device 4421 drives the driving arm 4429 to rotate; one end of the connecting rod 4426 is hinged to the driving arm 4429 through a first hinge shaft 4427, the other end of the connecting rod 4426 is hinged to the rocker arm 4422 through a second hinge shaft 4428, and although the positions of the first hinge shaft 4427 and the second hinge shaft 4428 are not required to be provided with the bearing 4430, preferably, the bearing 4430 is arranged between the connecting rod 4426 and the first hinge shaft 4427, and the bearing 4430 is also arranged between the connecting rod 4426 and the second hinge shaft 4428, so that the tilting process can be more stable. The tilting mechanism can realize a double-shaft connection structure with the tail wing 30 through the rotating shaft of the rocker arm 4422 and the rotating shaft of the driving arm 4429, and the moment born by the tilting mechanism can be increased by increasing the axial distance from the rotating shaft between the rocker arm 4422 and the tail wing 30 to the rotating shaft between the driving arm 4429 and the tail wing 30 so as to reduce the force born by a single rod, so that the tilting mechanism has stronger torsion resistance and improves the supporting rigidity of the whole rotor mechanism. And adopt this kind of mode that sets up can use unilateral to support, fix tilting mechanism on the aircraft, reduced the drive demand through four-bar linkage, simultaneously also can be very convenient through the length proportion between the adjustment four-bar linkage, can adjust the rigidity of whole mechanism, adjustment natural frequency to improve the mechanical properties of whole tilting rotor.

Referring to fig. 7 to 13, in this embodiment, a first shaft body 4423 and a second shaft body 4424 are fixedly disposed on the tail wing 30, one ends of the first shaft body 4423 and the second shaft body 4424 are fixed on the wing tip of the tail wing 30, the other ends of the first shaft body 4423 and the second shaft body 4424 are cantilevered, the rocker arm 4422 is rotatably mounted on the first shaft body 4423 through a bearing 4430, the driving arm 4429 is rotatably mounted on the second shaft body 4424 through a bearing 4430, the base of the tilting driving device 4421 is rotatably mounted on the first shaft body 4423 through a holding structure 4425 and is positioned along the axial direction of the first shaft body 4423, and the driving end of the tilting driving device 4421 is coaxial with the second shaft body 4424 and fixedly connected with the driving arm 4429. In this arrangement, the tilting drive device 4421 can be positioned and mounted together by the clasping structure 4425 and the second shaft body 4424, and the difficulty in mounting the tilting drive device 4421 can be reduced. In other embodiments, the tilting driving device 4421 may be fixedly disposed on the tail wing 30, and the output shaft of the tilting driving device 4421 may extend out to be fixedly connected with the driving arm 4429, so that the driving link 4426 drives the rocker arm 4422 to tilt. However, compared with the present embodiment, the arrangement mode occupies a larger space inside the tail wing 30, is not suitable for the situation that the wing profile is thinner or the internal equipment is more, and simultaneously causes the torque applied to the tilting drive device 4421 to be born by the mounting seat of the tilting drive device 4421, thereby having a larger requirement on the mounting strength of the tilting drive device 4421.

It should be noted that, considering that the single-side installation of the whole tilting mechanism, the longer extending distance of the first shaft 4423 may cause the bending moment of the first shaft 4423 to increase, and preferably, referring to fig. 12, in an embodiment, the first shaft 4423 and the tail wing 30 are installed with a matching surface 4432 that is longer along the axial direction, so that the installation length of the first shaft 4423 may be increased, the contact area between the first shaft 4423 and the base of the tilting driving device 4421 may be increased, so as to balance the bending moment of the first shaft 4423, further reduce the bending deformation of the first shaft 4423, and improve the installation stability of the whole mechanism.

In an embodiment of the invention, a distance from a rotation center line of the tilting driving device 4421 to an axis of the second hinge shaft 4428 is a, a distance from an axis of the first hinge shaft 4427 to an axis of the second hinge shaft 4428 is b, a distance from a center line of the first shaft 4423 to an axis of the first hinge shaft 4427 is c, a distance from a center line of the first shaft 4423 to a center line of the second shaft 4424 is d, a is smaller than b, c, and d, c is larger than b and d, respectively, and a sum of a and c is smaller than a sum of b and d. Therefore, once the tilting driving device 4421 is out of control, the output shaft of the tilting driving device 4421 is always in a forward or reverse rotating state, the rocker 4422 swings, namely the rocker 4422 rotates anticlockwise after rotating clockwise to the limit position and rotates clockwise after rotating anticlockwise to the limit position, the movable range of the tilting mechanism is limited, the tilting mechanism cannot rotate beyond the range to collide with other components to interfere with the other components, and the front end screw propeller of the tilting mechanism is prevented from colliding with the machine body and other structures to damage the machine body due to tilting overreach. Therefore, the invention can restrict the tilting angle range of the tilting mechanism by adjusting the length proportion of each part in the tilting mechanism, and simultaneously skillfully realizes the limit problem of the tilting mechanism, so that the limit position of forward rotation and the limit position of reverse rotation of the tilting mechanism are both at the same limit position of the connecting rod, the skillfully design not only can effectively ensure the safety of the mechanism, but also simplifies the design, does not need to additionally arrange a limit mechanism to limit the limit position, and greatly optimizes the installation space of the motion process of the transmission rod mechanism; specifically, by adjusting the length ratio of each component (i.e., a, b, c, d in fig. 9) in the link mechanism so that the distal axis (i.e., the axis of the second hinge shaft 4428) of the driving arm 4429 in the initial angle state (i.e., the tilting minimum angle) and the distal angle state (i.e., the tilting maximum angle) is equidistant from the axis of the first shaft 4423, and at this time, the angle between the axis of the distal end of the driving arm 4429 in the initial angle state and the axis composition plane of the first shaft 4423 and the axis composition plane of the distal end of the driving arm 4429 in the distal angle state and the axis composition plane of the first shaft 4423 is equal to the angle ±5° by which the rocker 4422 rotates, it is possible to achieve a limit point to restrict two directions.

In the invention, the first shaft body 4423 and/or the second shaft body 4424 are hollow shafts, and can be threaded and connected with the cables and the pipelines, so that the cables and the pipelines are prevented from being damaged by irregularly swinging outside, and meanwhile, the moving range of the cables and the pipelines is reduced, and the cables are prevented from being damaged. Considering that the second shaft 4424 needs to bear a large load, in this embodiment, the first shaft 4423 is preferably a hollow shaft, and the second shaft 4424 is preferably a solid shaft, however, in other embodiments, if the second shaft 4424 can bear a large load, the second shaft 4424 may be a hollow shaft, or both the first shaft 4423 and the second shaft 4424 may be hollow shafts.

In the embodiment, the tilting mechanism has different reduction ratios at different angles, so that the control precision requirements at different angles are realized, the structure is compact, and the space requirements are reduced in a centralized manner. Through the use of multiple connecting rods, the reduction ratio is changed along with the change of angles, the reduction ratio at a large load can be increased, the reduction ratio at a small load is reduced, the peak driving moment is reduced, and the driving requirement is reduced. The tilting driving device 4421 is of a rotary driving structure, and can amplify driving force through a brake or reduction ratio adjusting device in the tilting device, so that torque born by an executing end can be overcome, state keeping at any position can be realized, the current state position can be kept when driving fails, work can be continued after driving is recovered, and structural components can be arranged more intensively.

A first horn 511 is installed on the wing 20 on one side of the fuselage 10, and a second horn 521 is installed on the wing 20 on the other side of the fuselage 10; the first horn 511 and the second horn 521 are symmetrically arranged about a symmetry plane 60 of the fuselage 10, and the 2N fixed rotors are symmetrically mounted on the first horn 511 and the second horn 521 at two sides of the fuselage 10, respectively, and are located at front and rear sides of the wing 20 and front and rear ends of the first horn 511 and the second horn 521, respectively, and simultaneously, projections of all the fixed rotors on a horizontal plane are symmetrical about a point a of the vertical take-off and landing aircraft in a two-to-two correspondence manner.

In an embodiment of the vertical takeoff and landing aircraft of the present invention, the wing 20 on both sides of the fuselage 10 is provided with an organic arm, N is a natural number greater than or equal to 2, and 2N of the fixed rotors are symmetrically installed on the organic arms on both sides of the fuselage 10 and are respectively located on the front and rear sides of the wing 20. In order to realize distribution on the front side and the rear side of the center of gravity of the aircraft, and respectively realize the plane symmetry and the center symmetry relation of the aircraft body. The number of the tilting rotors is at least four, and of course, if energy is not considered, the number of the tilting rotors can be six, eight or even more, so long as the tilting rotors are added on the basis of the four tilting rotors, and the newly added tilting rotors also meet the relationship of plane symmetry about the machine body and center symmetry about the point B. The number of the fixed rotor wings is at least four in the application, if energy is not considered, the number of the fixed rotor wings can be six, eight or more even number, so long as the fixed rotor wings are added on the basis of the four fixed rotor wings, the fixed rotor wings are positioned on the outer sides of all the tilting rotor wings, and the newly added fixed rotor wings are satisfied with the plane symmetry and the center symmetry relation about the point A.

In one embodiment of the inventive vertical takeoff and landing aircraft, at least a portion of the 2N tiltrotors are disposed forward of the center of gravity and at least a portion of the tiltrotors are disposed aft of the center of gravity. Of the 2N stationary rotors, at least part is disposed on a front side of the center of gravity of the vertical takeoff and landing aircraft, and at least part is disposed on a rear side of the center of gravity of the vertical takeoff and landing aircraft. Therefore, the balance of multiple couples can be realized, and the vertical take-off and landing process of the vertical take-off and landing aircraft can be more stable.

In the vertical takeoff and landing aircraft of the present invention, the structural form of the elevator 31 can refer to the structure of the existing elevator 31, referring to fig. 1 and 13, in this embodiment, the elevator 31 includes a rudder plate 311 and a rudder body driving device (not shown), the rudder plate 311 is rotatably connected to the tail of the tail wing 30 or the fuselage 10, and the rudder driving device drives the rudder plate 311 to rotate so as to adjust the direction of the vertical takeoff and landing aircraft. The elevator 31 drive includes, but is not limited to, a motor, or a combination of a motor and a speed reducer.

Referring to fig. 22, in an embodiment of the vertical take-off and landing aircraft of the present invention, the ratio of the chord length of the rudder plate 311 to the chord length of the tail wing 30 is 15% -100%, for example, may be any value between 15%, 30%, 45%, 60%, 90%, 100%, etc. 15% -100%, and as an example, as shown in fig. 15, the chord length of the rudder plate 311 accounts for 30% of the chord length of the tail wing 30; as shown in fig. 16, the chord length of the rudder plate 311 is 60% of the chord length of the tail wing 30; as shown in fig. 17, the chord length of the rudder plate 311 is 100% of the chord length of the tail wing 30, but is not limited to the ratio of fig. 15 to 17. Note that, referring to fig. 21, the chord length is the distance from the front edge point to the rear edge point of the section of the airfoil of the tail wing 30, and the chord length ratio is the ratio of the length of the rudder plate on the tail wing 30 in the direction of the flight to the length of the tail wing 30 (not the length ratio in the direction of the span Y) in the plan view.

Referring to fig. 13, in an embodiment of the vertical takeoff and landing aircraft according to the present invention, the initial position of the vertical takeoff and landing aircraft parallel to the tail wing 30 is 0 °, the upward deflection is positive, the downward deflection is negative, and the deflection angle of the rudder plate 311 is-90 ° to 30 °, for example, any angle between-90 ° to 30 ° such as-90 °, -60 °, -30 °, -15 °, 0 °, 15 ° and 30 ° can be shown in fig. 20.

In an embodiment of the vertical take-off and landing aircraft according to the present invention, 2N of the rotation axes of the tilt rotors and 2N of the fixed rotors may be disposed along a vertical direction, preferably referring to fig. 5, in which 2N of the tilt rotors are symmetrically disposed at two sides of the fuselage 10, and an angle α between a plane formed by the rotation axes of the tilt rotors (i.e., a plane formed by the rotation axes of the tilt rotors rotating around the tilt axis center) and a plane 60 of symmetry of the fuselage 10 during tilting is-15 ° to +15°, for example, any angle between-15 °, -10 °, 0 °, 10 °, 15 ° and-15 ° to +15 ° may be used, and the angle may be positive in a direction from bottom to top, and negative in a direction from bottom to top. The included angle between the rotation axes of the 2N fixed rotor wings and the symmetrical plane of the machine body is-15 to +15, for example, any angle between-15, -10, -0, -10, -15 and the like can be formed, and the angle is positive in a manner of expanding from bottom to top to the outside, and negative in a manner of tilting from bottom to top to the symmetrical plane 60.

In the present invention, the tail wing 30 may be any one of a V-type tail wing, a Y-type tail wing, an H-type tail wing, an X-type tail wing, a T-type tail wing, an H-type tail wing, or a U-type tail wing, and the tilt rotor on the tail wing 30 is mounted on the upper side of the tail wing 30 and is tilted upward in a vertical take-off and landing state. This reduces the likelihood of injury to the occupant as the occupant enters and exits the aircraft. Referring to fig. 1 to 5, in the present embodiment, the tail wing 30 is a V-shaped tail wing, two tilt rotors are mounted on the tail wing 30, and the two tilt rotors are respectively mounted on two wing tips on the upper portion of the tail wing 30. The flight 30 may be any of the shapes described above in other embodiments.

during the flying process, distributing the pitch control proportion of the elevator 31 to 2N tilt rotors and 2N fixed rotors according to the current airspeed or dynamic pressure; according to the pitch control ratio, the elevators 31, 2N of the tiltrotors, and 2N of the fixed rotors are controlled respectively to achieve pitch balancing and manipulation.

In one embodiment of the vertical takeoff and landing aircraft of the present invention, controlling 2N of said tiltrotors according to said pitch control ratio includes: the tilting angle differential adjustment process comprises the following steps: i.e. by the tilt angle difference between said tilt rotor on tail 30 and any other said tilt rotor on the front side of tail 30, the pitching moment is differentially adjusted for pitch balancing and steering. And/or rotational speed differential adjustment process: namely, the pitching moment is differentially regulated to pitch balancing and manipulation through the rotation speed difference between the tilting rotor on the tail wing 30 and any other tilting rotor on the front side of the tail wing 30; and/or, a tilting speed differential adjustment process: i.e. by differential adjustment of the pitching moment for pitch balancing and steering by the difference in the tilting speed of the tilting rotor on the tail 30 and any other tilting rotor on the front side of the tail 30. It should be noted that the above-mentioned tilting angle differential adjustment process, rotation speed differential adjustment process, tilting speed differential adjustment process may be implemented individually or in combination with each other, or may be implemented in three embodiments at the same time.

As shown in fig. 24, the ground state to cruise state of the existing vertical takeoff and landing aircraft generally includes four phases:

S100, a ground preparation process.

In the ground preparation process, the vertical take-off and landing aircraft needs to be started first, the system is electrified and detected, and then the full stroke state of the servo systems such as the tilting mechanism, the elevator 31 and the like is confirmed.

S200, taking off control process. The process is mostly a process that the vertical take-off and landing aircraft ascends to a set height from the ground, and in the process, the tilting rotor and the fixed rotor keep the tilting angle and the rotating speed unchanged, and the process is relatively stable relative to the process of flying in a leveling manner.

S300, taking off and turning to the flat flight control process.

The control process of taking off and leveling is mainly involved in the change of the tilting angle of the tilting rotor wing and/or the change of the rotating speed of the tilting rotor wing and/or the fixed rotor wing, so that the pitching impact force applied in the process is large, and the control of the vertical take-off and landing aircraft is relatively difficult. As an optimization, referring to fig. 25, the take-off and turn-to-flat flight control process in the embodiment at S300 includes the following steps:

s310, responding to the fly-flat instruction. The plane flight instruction can be issued by a pilot or by the vertical take-off and landing aircraft when judging that the preset flight condition is met.

S320, a rotor wing control process. The process is greatly affected by the takeoff control process of S200, and may vary greatly depending on the state of the tiltrotor.

S330, a pitching control process. Considering that the tilting rotor is tilted to the set cruising position with the rotation axis of the tilting rotor parallel to the rolling axis for multiple times in the process of taking off and leveling, and the vertical take-off and landing aircraft receives a certain pitching impact force in the process of each tilting, step S330 can be performed after each S320 rotor control process of taking off and leveling.

S340, repeating the rotor control process and the pitch control process in sequence until the tilt rotor is tilted to a cruising position (for example, a position where the rotation axis of the tilt rotor is parallel to the roll axis when the tilt angle is 0 °).

For example, referring to fig. 28, in an embodiment of the control method of the present invention, the following take-off process is further included before the rotor control process in S320:

s211, 2N tilting rotors are tilted to a vertical lifting position or a tilting position (for example, between 0 and 90 degrees) of a rotation axis so as to power climbing together with the fixed rotors. The vertical take-off and landing position can be a position where the rotation axis of the tilting rotor forms an included angle of 90 degrees with the rolling shaft; the tilt position may be a position between 0-90 (excluding the end point value) between the axis of rotation of the tilt rotor and the roll axis.

S212, the elevator 31 is deflected downwards, so that the elevator 31 participates in the take-off control.

S213, starting 2N fixed rotors and 2N tilting rotors, and sending out a plane flight instruction when the vertical take-off and landing aircraft reaches a set height.

During the take-off process of S211 to S213, if the tilt rotor is disposed at 90 °, the vertical take-off and landing aircraft will take-off normally, and 2N fixed rotors and 2N tilt rotor throttle may be started to be consistent, for example, when N is equal to 2, there are four fixed rotors and four tilt rotors, and eight-axis eight-oar may be simultaneously output. At this time, the tilt rotor wing of the tail wing 30 has the largest shielding area in the vertical stage and the transition stage, and can induce a larger head-up moment. If the rotation axes of all the tilting rotors are placed at the inclined positions between 0 and 90 degrees, the inner tilting rotor starts an accelerator when the aircraft takes off, and the inner tilting rotor provides a forward tension component when the aircraft climbs upwards, and when the flying speed is gradually increased, the tilting angle of the inner tilting rotor is gradually reduced until the aircraft tilts to a set cruising position (for example, a position parallel to the 0-degree rotation axis) to turn into a flat flight fixed wing mode. According to the scheme, the aircraft has moderate head-up moment caused by the fact that the tail wing 30 shields the tilting rotor, the control difficulty is small, and the requirement on the maximum tension allowance of the power system is small.

Considering that the tilt rotor is in the vertical take-off and landing position or the tilt position during the take-off process of S211 to S213, referring to fig. 25 and 27, in an embodiment of the control method of the present invention, the rotor control process of S320 further includes the following steps:

s321, acquiring the current tilting position of each tilting rotor wing. The process can provide an angle sensor or a position sensor on the tilting rotor so as to feed back the current tilting position to the flight control system, or can directly feed back the corresponding current tilting angle position to the flight control system through the tilting driving device 4421.

S322, if the current tilting position is inconsistent with the set cruising position, acquiring the current airspeed or dynamic pressure of the corresponding tilting rotor wing at the current tilting position, and judging whether the current airspeed or dynamic pressure is equal to or greater than a preset threshold value at the current tilting position. The set cruising position is a position where the preset vertical take-off and landing aircraft is in a flat flight state, and may be, for example, a 0 ° position where the rotation axis of the tiltrotor is parallel to the roll axis X, or may be another position between 0 ° ± 5 °.

And S323, if the current airspeed or dynamic pressure is equal to or greater than a preset threshold value at the current tilting position, controlling the tilting rotor to tilt to a preset next position.

S324, gradually increasing the rotating speeds of the 2N tilting rotors, and gradually reducing the rotating speeds of the 2N fixed rotors to the set rotating speed.

However, in another embodiment of the present invention, referring to fig. 29, the S200 take-off process is different from the processes of S211 to S213 in fig. 28, and the S200 take-off process includes:

s221, tilting 2N tilting rotors to the front direction of the rotation axis horizontally and parallel to the rolling axis X;

s222, deflecting the elevator 31 downwards;

s223, starting 2N fixed rotors and 2N tilting rotors, and sending out a plane flight instruction when the vertical take-off and landing aircraft reaches a set height.

In the take-off process in S221 to S223, the rotation axes of all the tilting rotors are set at 0 ° (as shown in fig. 17), the aircraft is changed into a compound wing mode, the aircraft is taken off vertically by the four outer rotors, the output of the four outer rotors is twice as high as that of the first control scheme, the four tilting rotors on the inner side are gradually started in the transition stage of vertical flattening, the throttle is gradually increased until flattening is successful, the shielding area of the tail wing 30 of the tilting rotor in the scheme is minimum, the head-up moment generated is minimum, the control is the simplest, the control mode is basically the compound wing control mode, but the required tension margin of a power system is larger, the requirement on the power system is higher, and the control mode is reduced in a non-emergency condition.

As will be appreciated by those skilled in the art, since the axis of the tiltrotor is always parallel to the roll axis X during take-off in S221 to S223, the relevant process of S321 to S323 is no longer required during the S320 rotor control in the S300 take-off and level flight control, and only the rotational speeds of 2N tiltrotors need to be increased gradually and the rotational speeds of 2N fixed rotors need to be reduced gradually to the set rotational speeds.

However, it should be noted that, whether the rotor wing control process of S320 has the tilting control process of S321 to S323, the rotor wing control process receives a relatively high pitching impact force during the process of taking off and turning to flat flight, and therefore, referring to fig. 26, the present invention further provides a control method of the vertical take-off and landing aircraft for the vertical take-off and landing aircraft, which specifically includes the following pitching control process:

and S332, distributing the pitching control proportion of the elevator 31 to 2N tilting rotors and 2N fixed rotors according to the current airspeed or dynamic pressure. In this process, according to the current speed of the current vertical take-off and landing aircraft, the pitch adjusting force is distributed to the elevator 31, 2N of the tilt rotors and 2N of the fixed rotors according to a set distribution rule, so as to achieve relatively balanced pitch control through the pitch control proportion.

S333, according to the pitch control proportion, the elevator 31, 2N tilt rotors and 2N fixed rotors are respectively controlled to realize pitch balancing and operation. In this process, the flight control system controls the elevator 31, 2N of the tiltrotors and 2N of the fixed rotors according to the allocated pitch control proportion, for example, may be rotational speed differential control, deflection of the elevator 31, and the like, so that different pitch adjusting forces are generated at different positions of the vertical take-off and landing aircraft, so as to balance with the pitch impact force in the process of flying in a roll-off manner.

According to the vertical take-off and landing aircraft, 2N tilting rotors are arranged on the inner sides of 2N fixed rotors, and the elevating rudder 31 and the full-tilting rotors are arranged on the tail wing 30, so that the pitching impact force in the process of flying in a leveling manner can be balanced through the pitching control process, and a more stable control process can be obtained on one hand. On the other hand, in the pitching control process, the power nacelle of the tail wing 30 rotates along with the rotor wing in the tilting process, and the shielding area of the power nacelle in the corresponding rotor wing is smaller when hovering, so that the area of the rotor wing down wash on the tail wing 30 is smaller, a part of head-up moment can be reduced, and the control of the pitching moment of the vertical take-off and landing aircraft under a complex interference flow field can be improved.

In consideration of the fact that the elevator 31 is involved in the control process during the take-off of the vertical take-off and landing aircraft, the pitch control process according to the present invention further includes, before step S332: further comprising step S331 of controlling the elevator 31 to return to zero or to a trim rudder deflection value matching the current airspeed/dynamic pressure according to the current airspeed or dynamic pressure and to participate in the pitch control process step by step. For example, an airspeed threshold may be set and elevator 31 is zeroed back to its initial position without deflection when the current airspeed is greater than or equal to the set airspeed threshold, at which point the rudder deflection angle is 0 °.

The control method of the present invention may further include:

s400, in a cruising state, the vertical take-off and landing aircraft flies horizontally, and the aircraft sails along the horizontal direction and is relatively stable.

Referring to fig. 21, fig. 21 is a graph of full plane pitching moment generated by comparing the partial pitch scheme of the nacelle of the rotor tilting on the tail wing 30 with the full pitch scheme of the nacelle of the rotor tilting on the tail wing 30 through aerodynamic simulation analysis. The first curve 101 is a simulation curve of the simulation model in fig. 2, the structure of the tilting rotor at the tail part is referred to in fig. 14 during the pneumatic simulation analysis, the second curve 102 is a partial tilting model, which is different from the vertical takeoff and landing aircraft model in fig. 2 only in the structure of the tilting rotor on the tail wing 30, and the rest is the same except that the structure of the tilting rotor on the tail wing 30 is referred to in the power nacelle part tilting scheme in fig. 22. In the simulation analysis in the two models, the rotational speeds of the four fixed rotors and the four tilting rotors are equal and the pulling force matches the aircraft takeoff weight (pulling force versus gravity trim state).

In fig. 23, a first curve 101 and a second curve 102 are respectively curves of change of pitching moment of two full-plane models along with flying speed (i.e. wind speed), in which flying speed is subjected to dimensionless processing, and a process of 0-1 is that an aircraft flies from a hovering state to a maximum speed under a current tilting angle (the 90-degree tilting angle is kept unchanged), namely, flies from a minimum speed to the maximum speed under the current tilting angle; the pitching moment in the figure is also dimensionless.

As can be seen from a comparison between the first curve 101 and the second curve 102 in fig. 23, when 8 rotors have no front-rear accelerator differential motion, the aircraft generates a larger pitching moment, so that when the aircraft is required to fly smoothly, the pitching moment needs to be trimmed, and the pitching angular acceleration is 0, and when the aerodynamic pitching moment is trimmed, the front-rear rotor accelerator differential motion is required, so that the pitching moment generated by the rotor differential motion and the aerodynamic pitching moment generated by the aircraft body are offset. The pod full pitch scheme control method requires 0.25 units for maximum pitch trim and maneuvers generated during flight. The control method of the tilting scheme of the power nacelle part requires 0.8 unit for the maximum pitching trimming and operation of the whole aircraft, which is greatly larger than that of the full tilting control method, the larger the pitching moment generated in the flight process is, the more difficult the aircraft is to control, and the larger the additional power required for adjusting the attitude of the aircraft is for the power system. In addition, as can be seen from the simulation curve shown in fig. 23, as the flying speed is higher, the pitching trim and the manipulation demand fluctuation generated by the control method of the tilting scheme of the power nacelle part are also higher, the pitching moment fluctuation is about 0.8 from minus 0.04 in a hovering state (the dimensionless wind speed is 0.57), and the pitching moment fluctuation is very severe, so that the pitching control of the aircraft is very unfavorable; the pitching moment generated by the control method of the full tilting scheme of the anti-observation power nacelle is changed from minus 0.25 in a hovering state (the dimensionless wind speed is 0.42) to about 0.25, the pitching moment fluctuation is small, and the control of the pitching direction of the aircraft is facilitated.

In summary, according to the vertical take-off and landing aircraft disclosed by the invention, 2N tilting rotors are arranged on the inner sides of 2N fixed rotors, and the lifting rudder and the full-tilting rotor are arranged on the tail wing, so that on one hand, the power nacelle rotates along with the rotor in the tilting process of the tail wing tilting rotor, and when in hovering, the shielding area of the power nacelle in the corresponding rotor is smaller, therefore, the area of the rotor for down-washing flow to the tail wing is smaller, a part of head-up moment can be reduced, the control of the pitching moment of the vertical take-off and landing aircraft under a complex interference flow field can be improved, and on the other hand, the pitching balancing and the operation can be further carried out through coordination of the fixed rotor, the tilting rotor and the lifting rudder.

Further, for the manned vertical take-off and landing aircraft, the arranged manned seats are arranged on the front fuselage, so that the passengers and the luggage weight are relatively forward, the vertical take-off and landing aircraft layout mode is extremely friendly to the counterweight of the aircraft, and when passengers with different numbers of people are taken, the variation range allowed by the gravity center is relatively wide, so that the aircraft flight safety is facilitated.

Based on the beneficial effects, the invention effectively overcomes the practical problems in the prior art, thereby having high utilization value and use significance.

The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims

1. A vertical takeoff and landing aircraft, comprising:

the aircraft comprises an aircraft body, wherein wings are arranged on two sides of the aircraft body, a tail fin is arranged at the tail part of the aircraft body, and an elevator is arranged on the tail fin;

2N tilting rotors symmetrically arranged on two sides of the fuselage, wherein part of 2N tilting rotors are positioned on the tail wing, and at least the tilting rotors positioned on the tail wing are full tilting rotors;

2N fixed rotor wings symmetrically arranged on the wings on two sides of the fuselage and positioned on the outer sides of the tilting rotor wings;

wherein N is a natural number greater than or equal to 2, in a vertical take-off and landing state, projections of 2N fixed rotors on a horizontal plane are centrosymmetric about a point a, projections of 2N tilting rotors on the horizontal plane are centrosymmetric about a point B, and the point B, the point a and a gravity center G of the vertical take-off and landing aircraft are all located in a symmetry plane of the fuselage; in the process of transition from the vertical take-off and landing state to the cruising state of the vertical take-off and landing aircraft, the point G and the point B both move along the symmetrical plane to the side close to the nose, the point G is positioned at the side close to the nose or coincides with the point A, and the point B is always positioned at the side close to the tail wing.

2. The vertical takeoff and landing aircraft according to claim 1, characterized in that it comprises four said tilting rotors and four said fixed rotors, the distance from the center of gravity G point to the a point is L1, L1 is equal to or greater than 0, the distance from the a point to the B point is L2, L2 > 0, the pitch of four said fixed rotors along the extension direction of the fuselage is L3, the pitch of four said tilting rotors along the extension direction of the fuselage is L4, wherein 0.1 (l3+l4) is equal to or greater than 4l1+2l2 is equal to or greater than 0.01 (l3+l4).

3. The vertical takeoff and landing aircraft according to claim 1, characterized in that,

the tail wing is a V-shaped tail wing, two tilting rotors are mounted on the V-shaped tail wing, the two tilting rotors are mounted on wing tips of the V-shaped tail wing respectively, when in a vertical take-off and landing state, the distance between the rotation center of the tilting rotor wing on the tail wing and the front edge of the wing tip of the V-shaped tail wing is t1, the chord length of the wing tip of the V-shaped tail wing is t2, and the ratio of t1 to t2 is 15% -40%.

4. The vertical takeoff and landing aircraft according to claim 1, characterized in that,

and taking the rolling shaft of the vertical take-off and landing aircraft as a reference, defining the rolling shaft as 0 degree, taking the tilting rotor wing to tilt upwards to be positive, and tilting downwards to be negative, wherein the rotation axis of the tilting rotor wing tilts within the range of-20 degrees to 110 degrees.

5. The vertical takeoff and landing aircraft according to claim 1, characterized in that,

the full tilting rotor comprises a first rotor and a power nacelle, wherein the first rotor is connected with the power nacelle, the power nacelle is rotationally connected with the tail wing, and the power nacelle is synchronously tilted along with the first rotor in the tilting process of the first rotor.

6. The vertical takeoff and landing aircraft according to claim 5, characterized in that,

the center of the first rotor wing is provided with a fairing, and the projection of the fairing covers the projection of the power nacelle along the extending direction of the rotation axis of the first rotor wing.

7. The vertical takeoff and landing aircraft according to claim 5, characterized in that,

the power nacelle is a revolving body structure, and a revolving shaft of the revolving body structure and a rotating shaft of the first rotor wing are coaxially arranged; the surface of the power pod is in streamline arrangement.

8. The vertical takeoff and landing aircraft according to any of the claim 5 to 7, characterized in that,

the first rotor comprises a propeller and a rotation driving device, the propeller is mounted on an output shaft of the rotation driving device, the power nacelle comprises a nacelle shell and a tilting mechanism positioned in the nacelle shell, and the tilting mechanism is used for driving the rotation driving device to tilt so as to drive the propeller to tilt.

9. The vertical takeoff and landing aircraft according to claim 8, characterized in that said tilting mechanism includes:

10. The vertical takeoff and landing aircraft according to claim 9, wherein a first shaft body and a second shaft body which are parallel to each other are fixedly arranged on the tail wing, the rocker arm is rotatably installed on the first shaft body, the driving arm is rotatably installed on the second shaft body, the seat body of the tilting driving device is installed on the first shaft body, and the driving end of the tilting driving device is coaxial with the second shaft body and is fixed with the driving arm.

11. The vertical takeoff and landing aircraft according to claim 1, characterized in that the elevator comprises a rudder plate rotatably connected to the tail of the tail wing or the fuselage and a rudder body driving device that drives the rudder plate to rotate for adjusting the direction of the vertical takeoff and landing aircraft.

12. The vertical takeoff and landing aircraft according to claim 11, characterized in that the ratio of the chord length of the rudder plate to the chord length of the tail wing is 15% -100%.

13. The vertical takeoff and landing aircraft according to claim 11, characterized in that the deflection angle of the rudder plate is-90 ° to 30 ° with the initial position parallel to the tail wing being 0 °, with the upward deflection being positive and the downward deflection being negative.

14. The vertical takeoff and landing aircraft according to claim 1, characterized in that,

the included angles between the rotation axes of the 2N fixed rotor wings and the symmetrical plane of the machine body are-15 degrees to +15 degrees;

and/or the included angle between the plane formed by the rotation axes of the 2N tilting rotors in the tilting process and the symmetrical plane of the machine body is-15 degrees to +15 degrees.

15. The vertical takeoff and landing aircraft according to claim 1, characterized in that pitch control is performed by the following method:

in the flying process, distributing pitch control proportions of the elevator, 2N tilting rotors and 2N fixed rotors according to current airspeed or dynamic pressure;

16. The vtol aerial vehicle of claim 15 wherein controlling 2N of the tiltrotors according to the pitch control ratio comprises:

Differentially adjusting a pitching moment to perform pitching balancing and manipulation through a tilting angle difference between the tilting rotor on the tail wing and any other tilting rotor;

and/or, differentially adjusting the pitching moment to perform pitching trimming and manipulation through the tilting speed difference between the tilting rotor on the tail wing and any other tilting rotor.

17. A method of controlling a vertical takeoff and landing aircraft according to claim 1, characterized by the following pitch control procedure:

distributing pitch control proportions of the elevator and 2N tilt rotors and 2N fixed rotors according to current airspeed or dynamic pressure;

18. The control method of claim 17, wherein prior to distributing the pitch control ratio of the elevator to 2N of the tiltrotors and 2N of the fixed rotors according to the current airspeed or dynamic pressure, further comprising the following rotor control process:

Acquiring the current tilting position of each tilting rotor;

if the current tilting position is inconsistent with the set cruising position, acquiring the current airspeed or dynamic pressure of the corresponding tilting rotor wing at the current tilting position, and judging whether the current airspeed or dynamic pressure is equal to or greater than a preset threshold value at the current tilting position;

and gradually increasing the rotating speeds of 2N tilt rotors, and gradually reducing the rotating speeds of 2N fixed rotors to the set rotating speed.

19. The control method of claim 18, further comprising the following takeoff control process prior to said rotor control process:

deflecting the lifting rudder downward;

20. The control method of claim 17, further comprising the following take-off control process prior to the pitch control process:

Tilting 2N of said tiltrotors to an axis of rotation horizontally forward;

deflecting the lifting rudder downward;

21. The control method of claim 20, further comprising, after the takeoff control process, a pitch control process, followed by a rotor control process of: and gradually increasing the rotating speeds of 2N tilt rotors, and gradually reducing the rotating speeds of 2N fixed rotors to the set rotating speed.

22. A control method according to claim 19 or 21, characterized in that after gradually reducing the rotational speed of 2N of the fixed rotors to a set rotational speed, before the pitch control process, further comprising controlling the elevator to return to zero or to a trim rudder deflection value matching the current airspeed or dynamic pressure, and gradually participating in the pitch control process.

23. The control method according to claim 18, characterized in that the control method further comprises: and repeating the rotor wing control process and the pitching control process in sequence until the tilting rotor wing tilts to the cruising position, and completing taking off and leveling off.