Configuration-variable tilting four-rotor full-drive aircraft

Abstract

The variable-configuration tilting four-rotor full-drive aircraft comprises a center structure and rotor structures rotationally connected to the four corners of the center structure, and a rotor deflection structure is arranged in the center structure; the rotor wing deflection structure comprises a rack and a center steering engine arranged at the bottom of the rack, the center steering engine penetrates through the top of the rack to be connected with a center gear, racks are connected to the two sides of the center gear in a meshed mode respectively, T-shaped push rods in central symmetry are integrally connected to the positions, away from the center gear, of the two racks, and connecting rods are hinged to the two ends of each T-shaped push rod respectively. The length of the rack is larger than the stroke of the T-shaped push rod, and rotor wing deflection frames are hinged to the other ends, away from the T-shaped push rod, of the two connecting rods correspondingly and rotationally connected with the rotor wing structures; the load capacity and the energy efficiency of the tilting four-rotor full-drive aircraft can be improved by 29.3% to the maximum under the conditions that the omnidirectional flight capacity is not needed, such as longitudinal flight, pure pitch attitude transformation, fixed attitude hovering and longitudinal movement along the wall surface.

Description

Technical Field

[0001] The invention relates to the technical field of rotorcraft, and specifically discloses a variable-configuration tilt-rotating quad-rotor full-drive aircraft. Background Art

[0002] Existing ordinary quadrotor aircraft cannot achieve omnidirectional drive with six degrees of freedom or hover in any posture, are difficult to control and are not flexible enough in practical applications. Existing quadrotor aircraft that tilt around two axes perpendicular to each other on the horizontal plane have a large number of drives, are heavy and are not easy to control.

[0003] In order to achieve six-degree-of-freedom omnidirectional drive for existing quadrotor aircraft with single-degree-of-freedom tilting rotors, the deflection angle between each rotor tilt axis and the frame axis must be fixed, such as Figure 1 As shown in the figure, under this arrangement, the lateral force components of the pulling force generated after the tilting will cancel each other out between the rotors, and only the forward force component actually works. The forward force component value (positive direction of the x-axis) is T x =T V cos45°, where T x is the forward force value, T V It is the component of force in the horizontal plane after the rotor is tilted. When the quadcopter is in high-speed forward flight and when the pitch angle of the quadcopter is 90° and it moves longitudinally along the wall, the efficiency loss can be as high as 29.3%, which will cause great energy waste. In addition, a larger power motor is needed to generate the required pulling force to provide the required force and acceleration, which increases the cost requirements.

[0004] Therefore, the present invention proposes a rotor horizontal deflection mechanism for a tilt quadrotor aircraft and a variable configuration tilt quadrotor full-drive aircraft with the rotor horizontal deflection mechanism. Summary of the invention

[0005] In view of this, the present invention provides a variable configuration tilt-rotor quadrotor full-drive aircraft to solve the problems that existing ordinary quadrotor aircraft cannot achieve six-degree-of-freedom omnidirectional drive or hover in any posture, are difficult to control and are not flexible enough in practical applications. The aircraft can be transformed between omnidirectional flight configuration and longitudinal flight configuration through four rotor deflection frames that can be synchronously deflected horizontally. The load capacity and energy efficiency of the aircraft are greatly improved in situations where omnidirectional flight capability is not required, such as longitudinal flight, pure pitch attitude change and fixed attitude hovering, and longitudinal movement along a wall.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A variable configuration tilt-rotating quad-rotor full-drive aircraft, comprising a central structure and rotor structures rotatably connected to four corners of the central structure, wherein a rotor deflection structure is arranged in the central structure;

[0008] The rotor deflection structure includes a frame and a central servo arranged at the bottom of the frame. The central servo passes through the top of the frame and is connected to a central gear. Racks are respectively meshed and connected on both sides of the central gear. The two racks are integrally formed away from the central gear and are connected to a centrally symmetrical T-shaped push rod. Connecting rods are respectively hinged at both ends of the T-shaped push rod. The length of the rack is greater than the stroke of the T-shaped push rod. The other ends of the two connecting rods away from the T-shaped push rod are respectively hinged to rotor deflection frames, and the rotor deflection frames are rotatably connected to the rotor structure.

[0009] Furthermore, the rotor deflection frame is in a semicircular arc shape, a rotor tilt axis runs through the rotor structure, and the free end of the rotor deflection frame is rotatably connected to the rotor structure via a rotor tilt bearing.

[0010] Furthermore, the central structure includes a structural frame plate and a rack slide rail. The rack slide rail is fixedly installed below the structural frame plate to limit the sliding of the rack. The four corners of the structural frame plate are integrally connected with an arc-shaped slide rail with a J-shaped cross-section. The arc-shaped slide rail facilitates the smooth sliding of the rotor deflection frame.

[0011] Furthermore, the structural frame plate is adapted to the shape of the frame, and a group of pillars for fixing the frame and the structural frame plate are arranged at the four corners of the structural frame plate.

[0012] Furthermore, the rotor deflection frame includes a rotor deflection frame body and an arcuate slider with a J-shaped cross section, the arcuate slider is adapted to the arcuate slide rail, and the arcuate slider with a J-shaped cross section is arranged at one end close to the central structure.

[0013] The rotor deflection frame is connected to the central structure in rotation by sliding the arc-shaped slider of the J-shaped cross section in the arc-shaped slide rail of the J-shaped cross section.

[0014] Furthermore, a hanging ear structure is provided on the main body of the rotor deflection frame, and the hanging ear structure is hinged to the connecting rod.

[0015] Furthermore, when the T-shaped push rod is pushed out or retracted, the rotor deflection frames installed at the four corners of the frame deflect synchronously, and the deflection directions of two adjacent rotor deflection frames are opposite, and the deflection directions of two opposite rotor deflection frames are the same.

[0016] Furthermore, the rotor deflection frame body takes the center line of the frame as the axis. When the T-shaped push rod is in a retracted state, the deflection angle with the center line of the frame is 45°, and when the T-shaped push rod is in an extended state, the deflection angle with the center line of the frame is 90°.

[0017] The working principle and beneficial effects of this solution are:

[0018] 1. The variable configuration tilt-rotor quad-rotor full-drive aircraft disclosed in the present invention introduces the deflection capability of the rotor on the basis of the ordinary tilt-rotor quad-rotor full-drive aircraft, so that when the aircraft needs to perform longitudinal flight, pure pitch attitude change, fixed attitude hovering and longitudinal movement along the wall, only one driver can simultaneously drive all four rotors to deflect in the horizontal plane until the tilt axis is perpendicular to the longitudinal flight direction, and transform into a longitudinal flight configuration, and then generate a pulling force along the longitudinal direction of the fuselage through the tilt of the rotor, thereby avoiding the situation in which the lateral components of the pulling force of the rotors on both sides in the omnidirectional flight configuration offset each other and cause energy waste, and the load capacity and energy efficiency of the aircraft in longitudinal flight, pure pitch attitude change, fixed attitude hovering and longitudinal movement along the wall are significantly improved.

[0019] 2. The variable configuration tilt quad-rotor full-drive aircraft disclosed in the present invention has a rotor deflection structure arranged inside the central structure and at the four corners of the central structure; the rotor deflection structure includes a frame and a central servo arranged at the bottom of the frame, the central servo passes through the top of the frame and is connected to a central gear, the central gear is connected to two racks, the two racks are connected to T-shaped push rods away from the central gear, the two ends of the T-shaped push rods are respectively hinged to connecting rods, one end of the connecting rod away from the T-shaped push rod is hinged to a rotor deflection frame, the rotor deflection frame is connected to the frame of the central structure through a J-shaped cross-section arc slide rail of a shaftless structure; the rotor deflection frame is connected to the rotor tilt structure of the aircraft.

[0020] 3. The variable configuration tilt-quadrotor full-drive aircraft disclosed in the present invention has a rotor deflection mechanism designed to ensure that the four rotor tilt axes rotatably connected to the rotor deflection frame can be synchronously deflected in the horizontal plane with the same deflection angle, and the deflection directions of the tilt axes of two adjacent rotors are opposite, while the deflection directions of the tilt axes of two relative rotors are the same; when this condition is met, after the T-shaped push rod is pushed out to the extended state, the tilt axes of the four rotors can be simultaneously deflected to be perpendicular to the longitudinal axis of the fuselage, and after tilting, the rotor thrust has only a longitudinal component, thereby completing the transformation from the omnidirectional flight configuration to the longitudinal flight configuration.

[0021] 4. The variable configuration tilt-rotor quadrotor full-drive aircraft disclosed in the present invention has the ability to switch between omnidirectional flight configuration and longitudinal flight configuration while having the omnidirectional flight capability of a common tilt-rotor quadrotor full-drive aircraft. After changing to the longitudinal flight configuration, the aircraft can improve its load capacity and energy efficiency by up to 29.3% in situations where omnidirectional flight capability is not required, such as longitudinal flight, pure pitch attitude change and fixed attitude hovering, and longitudinal movement along the wall.

[0022] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a diagram showing the deflection angle between the tilt axis and the frame axis of an existing quad-rotor aircraft in the background technology of the present invention;

[0024] Figure 2 A schematic diagram of the mechanism motion of the variable configuration tilt-rotating quad-rotor full-drive aircraft of the present invention;

[0025] Figure 3 A top view of the overall structure of the variable configuration tilt quad-rotor full-drive aircraft of the present invention;

[0026] Figure 4 It is a schematic diagram of the structural frame plate in the variable configuration tilt quad-rotor full-drive aircraft of the present invention;

[0027] Figure 5 It is a side view of the overall structure of the variable configuration tilt quad-rotor full-drive aircraft of the present invention;

[0028] Figure 6 It is a schematic diagram of the rotor deflection structure in the variable configuration tilt quad-rotor full-drive aircraft of the present invention;

[0029] Figure 7 It is a schematic diagram of the assembly of the rotor structure and the rotor deflection frame in the variable configuration tilt quad-rotor full-drive aircraft of the present invention;

[0030] Figure 8 A schematic diagram of a J-shaped cross section in which a J-shaped cross section arc-shaped sliding block and a J-shaped cross section arc-shaped sliding rail in a variable configuration tilt-rotating quadrotor full-drive aircraft according to the present invention are slidably matched;

[0031] Fig. 9 It is a schematic diagram of the forward flight of the variable configuration tilt-rotating quad-rotor full-drive aircraft of the present invention in an omnidirectional flight configuration;

[0032] Fig.10 It is a schematic diagram of the forward flight of the variable configuration tilt-rotating quad-rotor full-drive aircraft of the present invention in the longitudinal flight configuration;

[0033] Fig.11 Schematic diagram of the variable configuration tilt quadrotor full-drive aircraft of the present invention hovering at a fixed pitch angle in an omnidirectional flight configuration and a longitudinal flight configuration, wherein Fig.11 (a) is a schematic diagram of a variable configuration tilt-rotating quadrotor fully-driven aircraft hovering at a fixed pitch angle in an omnidirectional flight configuration. Fig.11(b) is a schematic diagram of the variable configuration tilt-rotating quadrotor full-drive aircraft hovering at a fixed pitch angle in the omnidirectional flight configuration and the longitudinal flight configuration;

[0034] Fig.12 The present invention shows the relationship between the ratio of the thrust of a single rotor and the thrust of the variable configuration tilt quad-rotor full-drive aircraft in an omnidirectional flight configuration and a longitudinal flight configuration when the aircraft is hovering at a certain pitch angle as a function of the pitch angle θ.

[0035] The markings in the accompanying drawings are as follows: 1. Central structure; 2. Rotor deflection structure; 3. Rotor structure; 11. Structural frame plate; 12. Rack slide rail; 13. Pillar; 14. J-section arc slide rail; 21. Frame; 22. Central servo; 23. Central gear; 24. Rack; 25. T-shaped push rod; 26. Connecting rod; 27. Rotor deflection frame; 271. Rotor deflection frame body; 272. J-section arc slide block; 273. Ear structure; 31. Tilt shaft; 32. Tilt bearing. DETAILED DESCRIPTION

[0036] The following is further described in detail through specific implementation methods:

[0037] like Figure 2-8 A variable configuration tilt-rotating quad-rotor full-drive aircraft is shown, comprising a central structure 1 and a rotor structure 3 rotatably connected around the central structure 1 , wherein the rotor structure 3 is arranged at four corners of the central structure 1 , and the geometric centerline angle between two adjacent rotor structures 3 is 90°.

[0038] The rotor deflection structure 2 is arranged in the central structure 1. The rotor deflection structure 2 includes a frame 21 and a central steering gear 22 arranged at the bottom of the frame 21. The central steering gear 22 passes through the top of the frame 21 and is connected to a central gear 23. The rotor horizontal deflection structure 2 is arranged as a central symmetrical structure with the central gear 23 as the center. Racks 24 are respectively meshed and connected on both sides of the central gear 23. The two racks 24 are integrally formed and connected with a centrally symmetrical T-shaped push rod 25 away from the central gear 23. The two ends of the T-shaped push rod 25 are respectively hinged with connecting rods 26. The other ends of the two connecting rods 26 away from the T-shaped push rod 25 are respectively hinged with rotor deflection frames 27. The rotor deflection frame 27 is rotatably connected to the rotor structure 3 through a rotor tilt shaft 31. The rotor deflection frame 27 is in a semicircular shape. The rotor tilt shaft 31 runs through the rotor structure 27. The free end of the rotor deflection frame 27 is rotatably connected to the rotor structure 3 through a rotor tilt bearing 32.

[0039] The central structure 1 includes a structural frame plate 11 and a rack slide 12. The structural frame plate 11 is adapted in shape to the frame 21. The rack slide 12 is fixedly installed under the structural frame plate 11. A group of pillars 13 for fixing the frame 21 and the structural frame plate 11 are arranged at the four corners of the structural frame plate 11. The pillars 13 are fixedly connected to the frame 21, and the upper parts thereof pass through the threaded holes at the four corners of the structural frame plate 11 and are threadedly connected to the structural frame plate 11. The frame 21 and the structural frame plate 11 are fixedly connected using the pillars 13. The four corners of the structural frame plate 11 are integrally formed with an arcuate slide 14 with a J-shaped cross-section, and the arcuate slide 14 facilitates the sliding of the rotor deflection frame 27.

[0040] Specifically, the central steering gear 22 drives the central gear 23 to rotate, and then drives the rack 24 meshing with the central gear 23 to slide along the rack slide rail 12 below the structural frame plate 11, and the T-shaped push rods 25 are moved closer to or away from the central gear 23 through the rack 24, and the connecting rod 26 drives the rotor deflection frame 27 to rotate under the drive of the T-shaped push rod 25. When the central gear 23 rotates clockwise, the T-shaped push rod 25 and the rack 24 move toward the central gear 23, and the T-shaped push rod 25 is in an extended state after moving into position; when the central gear 23 rotates counterclockwise, the T-shaped push rod 25 and the rack 24 move away from the central gear 23, and the T-shaped push rod 25 is in a retracted state after moving into position.

[0041] The rotor deflection frame 27 comprises a rotor deflection frame body 271 and an arc-shaped slider 272 with a J-shaped cross section, the arc-shaped slider 272 is adapted to the arc-shaped slide rail 14, a lug structure 273 is provided on the rotor deflection frame body 271, the lug structure 273 is hinged to the connecting rod 26, the arc-shaped slider 272 with a J-shaped cross section is provided at one end close to the central structure 1, the rotor deflection frame 27 slides in the arc-shaped slide rail 14 with a J-shaped cross section to realize the rotational connection between the rotor deflection frame 27 and the central structure 1, and lubricating grease is filled between the arc-shaped slider 272 with a J-shaped cross section and the arc-shaped slide rail 14 with a J-shaped cross section. The connection structure composed of the arc-shaped slider 272 with a J-shaped cross section and the arc-shaped slide rail 14 with a J-shaped cross section is a shaftless structure, and its J-shaped cross section feature ensures the locking between the rotor deflection frame 27 and the fuselage in all directions except the sliding direction of the slide rail slider, and facilitates the manufacture of this structure using FDM additive manufacturing technology.

[0042] The rotor deflection frame body 271 of the rotor tilt-axis horizontal deflection structure takes the center line of the frame 21 as the axis. When the T-shaped push rod 25 is in a retracted state, the deflection angle with the center line of the frame 21 is 45°. When the T-shaped push rod 25 is in an extended state, the deflection angle with the center line of the frame 21 is 90°. The entire rotor horizontal deflection structure has good transitional flight capability. When converting from an omnidirectional flight configuration to a longitudinal flight configuration, the 45° deflection of the rotor deflection frame 27 can help the quadcopter to transition smoothly, and achieve efficient hovering and attitude change as well as longitudinal flight at a large pitch angle.

[0043] The rotor structure 3 is set as a central symmetrical structure with the central gear 23 as the center. The design of this rotor horizontal deflection mechanism makes the quadrotor aircraft have good balance. The central symmetrical design can ensure that the rotor remains balanced during the deflection process, reduce the vibration caused by the center of gravity offset, and improve the stability and flight efficiency of the quadrotor aircraft; it can make the load on each rotor more uniform, reduce the burden on a single rotor and transmission system, and extend the service life; by controlling the deflection of the rotor through the central gear, the quadrotor aircraft can achieve rapid response and flexible maneuverability in the air, which can be applied to a variety of flight modes and mission requirements.

[0044] During the specific implementation process, when the quadrotor aircraft needs to perform six-degree-of-freedom omnidirectional drive, the rack 24 is in the initial retracted state. In this state, the tilt axes of all rotor deflection frame bodies 271 are deflected 45° from the central axis of the frame 21; when the quadrotor aircraft needs to move purely longitudinally or is about to perform longitudinal flight, fixed attitude hovering, and longitudinal movement along the wall after a pure pitch attitude change, the central servo 22 rotates counterclockwise, and the central gear 23 fixedly connected to the central servo 22 drives the rack 24 to push the connecting rod 26 in a straight line along the rack slide 12. The connecting rod 26 pushes the rotor deflection frame 27 hinged thereto, and under the constraint relationship between the J-shaped cross-section arc slider 272 and the J-shaped cross-section arc slide 14, the rotor structure 3 is deflected 45° with the center of the J-shaped cross-section arc slide 14 as the center, so that the tilt axes 31 of the four rotor structures 3 are simultaneously deflected to be perpendicular to the axis of the frame 21. When moving longitudinally along the wall, the tilt axes 31 of the four rotor structures 3 can also be simultaneously deflected to any angle not less than 45° and not more than 90° with the longitudinal axis of the fuselage by the rotation of the central steering gear 22 .

[0045] In this embodiment, the dimensional parameters and mechanical parameters of each part of the mechanism are listed in order as follows: the tooth profile of the central gear 23 and the rack 24 is a standard involute tooth profile with a module of 1 and a pressure angle of 20°, the number of teeth of the central gear 23 is 24, the length of the rack 24 should be greater than the stroke of the T-shaped push rod, the length of the two arms of the T-shaped push rod 25 is 22mm each, the length of the connecting rod 26 is 75mm, the rotation radius of each rotor deflection frame 27 is 80mm, and the rotation center is 184mm from the center of the central gear 23; under this dimensional parameter, the stroke of the T-shaped push rod from the retracted state to the fully pushed out state of the mechanism is 62.7mm, and the pressure angle of the mechanism reaches a maximum value of 38.48 degrees when the mechanism is pushed out in the fully retracted state, and the pressure angle is less than 45 degrees, which is within a reasonable range. In the specific implementation process, the dimensions of each part of the mechanism can be enlarged or reduced by a certain multiple according to the same proportion of the dimensions of this example.

[0046] In the specific implementation process, if the horizontal deflection structure of the rotor tilt axis 31 follows the above-mentioned rod length ratio, it can be ensured that the four rotor tilt axes 31 rotatably connected to the rotor deflection frame 27 can be synchronously deflected in the horizontal plane, with the same deflection angle, and the deflection directions of the tilt axes 31 of two adjacent rotors are opposite, and the deflection directions of the tilt axes 31 of the two relative rotors are the same; if this condition is met, the rotor tilt axes 31 on both sides of the longitudinal axis of the fuselage are deflected in mirror symmetry, ensuring that when the rotor tilt axis is deflected to any angle of not less than 45° and not more than 9° with the longitudinal axis of the fuselage, The symmetry between the rotor thrust and the longitudinal axis of the fuselage at an angle of 0° is beneficial to the distribution of the total thrust and total torque vector acting on the center of mass of the fuselage, thereby calculating the corresponding thrust and tilt angle of each rotor; in addition, after the T-shaped push rod 25 is pushed out to the extended state, the tilt axes of the four rotors can be simultaneously deflected to be perpendicular to the longitudinal axis of the fuselage, that is, the horizontal deflection angle of each rotor tilt axis 31 is 90 degrees. In this way, after tilting, the rotor thrust has only a longitudinal component on the water surface, thereby successfully completing the transformation from the omnidirectional flight configuration to the longitudinal flight configuration.

[0047] In the specific implementation process, ordinary tilt-rotating quad-rotor full-drive aircraft usually calculates the required thrust and tilt angle of each rotor based on the required thrust and torque on the fuselage by using a control allocation method based on virtual control quantity and pseudo-inverse. Figure 9-10 For the selection of fuselage coordinate system.

[0048] Set virtual control quantity

[0049] H=[T1sinα1 T2cosα1......T4sinα4 T4cosα4] T

[0050] T i is the i-th rotor tilting force, α i For the tilt angle of each rotor,

[0051] AH=F

[0052] F=[f x f y f z τ x τ y τ z ] T , are the resultant force and resultant moment vectors, A is the distribution matrix, f is the component of the resultant force along the x, y, and z directions; τ is the component of the resultant moment around the x, y, and z axes.

[0053]

[0054] c is the air resistance moment coefficient of the rotor rotation, γ is the horizontal deflection angle of the rotor, and the Moore-Penrose pseudo-inverse is obtained for both sides at the same time.

[0055]

[0056] According to H, the control input vector corresponding to a certain F can be obtained and The elements of the vector are obtained by the following formula:

[0057] α i =arctan2(h 2i-1 ,h 2i )

[0058]

[0059] h is the component of H vector, and the expressions correspond to the elements of H vector in the above text.

[0060] In the omnidirectional flight configuration, γ is 45 degrees, and after the invention transforms it into the longitudinal flight configuration, γ is 0 degrees, and the allocation matrix is ​​simplified to

[0061]

[0062] c is the ratio of the rotor drag coefficient to the thrust coefficient; l is the distance from the rotor tilt axis to the center of the fuselage (i.e. the length of the lever arm).

[0063] Since in this configuration, the rotor tilts so that the rotor only provides force on the YOZ plane, the distribution of the total pulling force is reduced from a three-dimensional situation to a two-dimensional situation. Therefore, the calculation method based on virtual control quantity and pseudo-inverse can be omitted and the calculation can be further simplified to:

[0064] a i =arctan2(f x , f y )

[0065]

[0066] This reduces the computational complexity of the aircraft during longitudinal flight and improves the computational efficiency of the flight control computer.

[0067] A set of pitch-fixed attitude hovering examples are provided here to compare the thrust values ​​required for each rotor of a conventional tilt-rotating quad-rotor full-drive aircraft with that after being transformed into a longitudinal flight configuration through the present invention, so as to demonstrate the effect of the present invention on improving the thrust efficiency of the longitudinal flight of the full-drive aircraft.

[0068] Assume the total weight of the aircraft is 1.5 kg and the gravity acceleration is 10 m / s 2 , the fuselage is Fig.11 As shown, it hovers at a fixed attitude with a pitch angle θ∈[0°, 90°] in the XOZ plane. Fig.11 (a) is a schematic diagram of a variable configuration tilt-rotating quadrotor fully-driven aircraft hovering at a fixed pitch angle in an omnidirectional flight configuration. Fig.11 (b) is a schematic diagram of a variable configuration tilt-rotating quadrotor full-drive aircraft hovering at a fixed pitch angle in an omnidirectional flight configuration and a longitudinal flight configuration; Fig.12 As shown, the aircraft Fig. 9 The omnidirectional flight configuration hovering shown in FIG. 1 is a control allocation method based on virtual control amount and pseudo-inverse, and the required thrust of each rotor at each pitch angle is obtained by the solid line in the figure; it is transformed into the following by the present invention: Fig.10 After the longitudinal flight configuration shown, since the rotor can directly generate a pulling force opposite to gravity after tilting to the corresponding angle of the fuselage pitch angle θ, the pulling force required by each rotor is a constant value of 3.75N at each tilt fuselage pitch angle θ, which is represented by a dotted line in the figure; the dotted line in the figure represents the ratio of the pulling force required by a single rotor when the aircraft hovers in the longitudinal flight configuration and the omnidirectional flight configuration at each tilt fuselage pitch angle θ. It can be seen from the curve that the larger the fuselage pitch angle (that is, the larger the rotor tilt angle), the smaller the ratio, and both are less than 1, which proves that the present invention improves the pulling efficiency in the flight scenario where the aircraft only needs to generate the total pulling force on the XOZ plane, and the larger the rotor tilt angle, the more obvious the efficiency improvement, which can reach 29.3% at a tilt of 90°. That is, after the tilt quad-rotor full-drive aircraft is transformed in configuration by the present invention, it is particularly suitable for scenarios with large rotor tilt angles such as vertical hovering and longitudinal flight along the wall.

[0069] Therefore, the present invention adopts the above-mentioned variable configuration tilt-quadrotor full-drive aircraft, which is simple to operate and has fewer active parts, so that the load capacity and energy efficiency of the tilt-quadrotor full-drive aircraft can be improved by up to 29.3% in situations where omnidirectional flight capability is not required, such as longitudinal flight, pure pitch attitude change and fixed attitude hovering, and longitudinal movement along the wall.

[0070] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the present invention.

Claims

1. A variable configuration tilt-rotating quad-rotor fully-driven aircraft, characterized in that: It comprises a central structure (1) and a rotor structure (3) rotatably connected to four corners of the central structure (1), and a rotor deflection structure (2) is arranged in the central structure (1); The rotor deflection structure (2) comprises a frame (21) and a central steering gear (22) arranged at the bottom of the frame (21); the central steering gear (22) passes through the top of the frame (21) and is connected to a central gear (23); racks (24) are respectively meshed and connected to the two sides of the central gear (23); two racks (24) are integrally formed and connected to a centrally symmetrical T-shaped push rod (25) at a position away from the central gear (23); connecting rods (26) are respectively hinged at both ends of the T-shaped push rod (25); the length of the racks (24) is greater than the stroke of the T-shaped push rod (25); the other ends of the two connecting rods (26) away from the T-shaped push rod (25) are respectively hinged to rotor deflection frames (27); and the rotor deflection frames (27) are rotatably connected to the rotor structure (3).

2. The variable configuration tilt quad-rotor full-drive aircraft according to claim 1, characterized in that: The rotor deflection frame (27) is in a semicircular arc shape, a rotor tilt shaft (31) runs through the rotor structure (3), and the free end of the rotor deflection frame (27) is rotatably connected to the rotor structure (3) via a rotor tilt bearing (32).

3. The variable configuration tilt quad-rotor full-drive aircraft according to claim 1, characterized in that: The central structure (1) comprises a structural frame plate (11) and a rack slide rail (12); the rack slide rail (12) is fixedly mounted below the structural frame plate (11) and is used to limit the sliding movement of the rack (24); the four corners of the structural frame plate (11) are integrally formed with arcuate slide rails (14) having a J-shaped cross section; the arcuate slide rails (14) facilitate the smooth sliding of the rotor deflection frame (27).

4. The variable configuration tilt quad-rotor full-drive aircraft according to claim 3, characterized in that: The structure frame plate (11) is adapted to the shape of the frame (21), and a group of pillars (13) for fixing the frame (21) and the structure frame plate (11) are arranged at the four corners of the structure frame plate (11).

5. The variable configuration tilt quad-rotor full-drive aircraft according to claim 3 or 4, characterized in that: The rotor deflection frame (27) comprises a rotor deflection frame body (271) and an arc-shaped slider (272) with a J-shaped cross section. The arc-shaped slider (272) is adapted to the arc-shaped slide rail (14). The arc-shaped slider (272) with a J-shaped cross section is arranged at one end close to the central structure (1).

6. The variable configuration tilt quad-rotor full-drive aircraft according to claim 5, characterized in that: The rotor deflection frame body (271) is provided with a hanging ear structure (273), and the hanging ear structure (273) is hinged to the connecting rod (26).

7. The variable configuration tilt quad-rotor full-drive aircraft according to claim 5, characterized in that: When the T-shaped push rod (25) is pushed out or retracted, the rotor deflection frames (27) installed at the four corners of the frame (21) are deflected synchronously, and the deflection directions of two adjacent rotor deflection frames (27) are opposite, while the deflection directions of two opposite rotor deflection frames (27) are the same.

8. The variable configuration tilt quad-rotor full-drive aircraft according to claim 5, characterized in that: The rotor deflection frame (27) body takes the center line of the frame (21) as an axis, and when the T-shaped push rod (25) is in a retracted state, the deflection angle with the center line of the frame (21) is 45°, and when the T-shaped push rod (25) is in an extended state, the deflection angle with the center line of the frame (21) is 90°.

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