Aircraft ducted ring distributed omni-directional vector control system

Abstract

The application relates to the technical field of aviation aircraft, and particularly discloses a kind of aircraft duct ring distributed omnidirectional vector control systems, and front vector control device and rear vector control device are respectively arranged at the outlet end of front duct and rear duct, each vector control device includes multiple groups of independently arranged vector vane units, and the complete coverage duct outlet full flow cross section;The pivot shaft of each group of vector vane units is arranged along the radial direction of the duct, the guide blade spanwise is along the circumference of the duct, and the guide blade chordwise is along the axial direction of the duct.Front duct fan unit and rear duct fan unit are respectively arranged in front duct and rear duct, and the installation height of front duct fan unit is lower than that of rear duct fan unit.The vector control system of the application has simple structure, high fault tolerance rate, and can be widely applied to industrial-grade unmanned aircraft, urban low-altitude manned aircraft, special vertical take-off and landing aircraft and other scenes, and fully meets the airworthiness design requirements of civil aircraft.

Description

Technical Field

[0001] This invention belongs to the field of aircraft technology and relates to vector thrust control, attitude stabilization and flight control technology for tandem ducted twin-rotor aircraft. Specifically, it relates to a ducted circumferential distributed omnidirectional vector control system for aircraft. Background Technology

[0002] With the rapid rise of the urban air mobility (UAM) industry, the performance requirements for aircraft in special low-altitude operations are constantly increasing. With its core advantages such as compact structure, strong rotor protection, low flight noise, and high low-altitude safety, the tandem ducted twin-rotor aircraft has become a core technology direction with great development potential in the field of low-altitude aircraft.

[0003] Compared to traditional single-rotor aircraft with a tail rotor or coaxial twin-rotor layouts, ducted designs enclose the rotor within the duct shell, reducing the risk of rotor collisions with foreign objects and suppressing rotor noise, making them more suitable for low-altitude urban operations. The tandem ducted configuration offers better load balance and higher fuselage space utilization, adapting to heavy-load passenger transport, logistics, and special operations needs. However, tandem ducted twin-rotor aircraft still face core technological bottlenecks: achieving a balance between attitude stability, vector control accuracy, and overall aerodynamic efficiency during hovering and low-speed flight. Mainstream ducted vector control solutions in the industry all have inherent limitations that are difficult to overcome.

[0004] Existing technical solutions mainly fall into two categories: one is the inlet-end deflection control scheme, which generates horizontal control force by setting deflectable parallel blades at the duct inlet to change the intake direction. Although this solves the problem of reverse lateral force coupling in traditional outlet deflection, the blades directly block the intake, severely interfering with the intake airflow field, resulting in inherent defects such as large aerodynamic losses and a single control dimension. The other is the outlet-end deflection control scheme, which obtains control force by deflecting parallel blades at the duct outlet to change the wake direction. This type of scheme can only output horizontal force in a single direction and requires two stages of orthogonal blades to achieve multi-dimensional control. It suffers from complex structure, severe coupling of three-axis (pitch, roll, yaw) control, and low force efficiency. Furthermore, it cannot achieve 360° omnidirectional vector output for a single duct, making it difficult to adapt to the requirements of high-maneuverability flight.

[0005] For the specific layout of tandem dual ducts, existing technologies generally adopt the scheme of installing the front and rear ducts at the same height. Under this layout, the high-speed wake discharged from the front duct will directly impact the air intake of the rear duct, causing air intake distortion and flow field turbulence in the rear duct. Ultimately, this leads to a decrease in the lift efficiency of the rear duct by more than 20%, which significantly reduces the overall control accuracy and flight stability of the aircraft, and the advantages of the tandem layout itself cannot be fully utilized.

[0006] In addition to the aforementioned unique defects, existing ducted vector control systems also have many common problems: On the one hand, existing guide vanes mostly adopt fixed symmetrical airfoils, with a critical stall angle of attack of only 12°~16° and a maximum deflection angle limited to within 15°. Exceeding this angle will cause airflow separation, a sharp drop in control force, and an extremely narrow control boundary. On the other hand, existing integrated blade structures lack redundant fault-tolerant design. If a single drive fails, the corresponding directional control capability will be lost, which cannot meet the airworthiness requirements of manned aircraft. The complex mechanical structure also leads to high maintenance costs, low reliability, and difficulty in large-scale application.

[0007] In summary, the industry urgently needs a new type of ducted circumferential distributed omnidirectional vector control system for aircraft to meet the development needs of tandem ducted twin-rotor aircraft. Summary of the Invention

[0008] This invention aims to overcome the shortcomings of existing technologies and provide a ducted circumferential distributed omnidirectional vector control system for aircraft. This system can be widely applied to industrial unmanned aerial vehicles, urban low-altitude manned aircraft, and special vertical takeoff and landing aircraft, and fully complies with the airworthiness design requirements of civil aircraft.

[0009] To achieve the above objectives, the present invention provides a ducted circumferential distributed omnidirectional vector control system for an aircraft. The aircraft has a front duct and a rear duct arranged along its longitudinal axis. The omnidirectional vector control system includes a front vector control device, a rear vector control device, a front duct fan unit, and a rear duct fan unit. The front and rear vector control devices are respectively located at the outlet ends of the front and rear ducts. Each vector control device includes a vector control device housing, a central hub, and multiple independently arranged vector blade units. The central hub is located at the center of the vector control device housing. Each vector blade unit includes a first servo drive motor, guide vanes, and a pivot shaft. The first servo drive motor is disposed on the inner wall of the vector control device housing, and the output shaft of the first servo drive motor is connected to the pivot shaft. One end of the pivot shaft is connected to the drive shaft, and the other end of the pivot shaft is rotatably connected to the central hub; the pivot shaft is arranged radially along the duct and passes through the guide vanes, and the chord direction of the guide vanes is arranged axially along the duct; each guide vane can deflect independently under the drive of its first servo drive motor; the front duct fan unit and the rear duct fan unit are respectively arranged in the front duct and the rear duct, and below the corresponding vector control device; the front duct fan unit and the rear duct fan unit have a fixed height difference in the duct axial direction, and the installation height of the front duct fan unit is lower than the installation height of the rear duct fan unit; each duct fan unit includes a duct motor, a duct fan and a fan unit housing, the duct motor is connected to the duct fan and is used to drive the duct fan to rotate inside the fan unit housing.

[0010] Furthermore, the guide vane adopts a segmented flap-type variable camber structure and is divided into two parts along its airfoil chord direction, including a fixed main airfoil section and a deflectable flap section. The fixed main airfoil section is rigidly connected to the pivot shaft and can deflect as a whole with the pivot shaft. One end of the deflectable flap section is pivotally connected to the trailing edge of the fixed main airfoil section. A second servo drive motor and a bevel gear set are arranged in the cavity of the fixed main airfoil section. The second servo drive motor is connected to the bevel gear set for transmission to drive the deflectable flap section to deflect independently, thereby continuously changing the airfoil camber.

[0011] Furthermore, the bevel gear set includes a driving bevel gear and a driven bevel gear that mesh with each other. The driving bevel gear is disposed on the output shaft of the second servo drive motor, and the driven bevel gear is disposed on the rotating shaft that rotatably connects the deflectable flap section and the fixed main wing section. When the first servo drive motor drives the pivot shaft to rotate, the guide vane deflects with the pivot shaft, thereby realizing angle of attack adjustment. When the second servo drive motor drives the driving bevel gear to rotate, the driving bevel gear rolls circumferentially along the tooth surface of the driven bevel gear, thereby driving the deflectable flap section to deflect synchronously around the rotating shaft.

[0012] Furthermore, the second servo drive motor is a miniature servo drive motor; two second servo drive motors are provided in the cavity of the fixed main wing section, respectively located at both ends of the cavity of the fixed main wing section, and each second servo drive motor is connected to a bevel gear set.

[0013] Furthermore, the deflection range of the guide vane is -25° to +25°; the deflection range of the deflectable flap section is -20° to +20°.

[0014] Furthermore, the guide vanes in the front vector control device adopt a high lift-to-drag ratio reference airfoil, with a rated operating angle range of -18° to +18° and an absolute limit protection angle of -25° to +25°; the guide vanes in the rear vector control device adopt a high lift coefficient reference airfoil, with a rated operating angle range of -22° to +22° and an absolute limit protection angle of -25° to +25°.

[0015] Furthermore, each of the vector control devices includes 8 sets of the vector blade units; the fixed main wing section accounts for 65% to 75% of the chord length, and the rear deflectable flap section accounts for 25% to 35% of the chord length.

[0016] Furthermore, the height difference between the front duct fan unit and the rear duct fan unit is 25-40% of the duct diameter; the distance between the centerlines of the front duct and the rear duct in the longitudinal axis direction of the fuselage is 1.8-2.5 times the duct diameter.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention provides a circumferentially distributed omnidirectional vector control system for an aircraft duct, comprising two main modules: a vector control device and a longitudinal elevation difference layout of the entire aircraft. The front vector control device and the rear vector control device are respectively located at the outlet ends of the front and rear ducts. Each vector control device includes eight sets of vector blade units evenly arranged 360° around the duct to completely cover the full flow section of the duct outlet. The pivot axis of each set of vector blade units is arranged radially along the duct, the blade span is along the circumferential direction of the duct, and the blade chord is along the axial direction of the duct. Each set of vector blade units is equipped with an independent waterproof first servo drive motor, which is fixed to the inner wall of the outer ring of the duct and the central hub. The output end is rigidly connected to the blade pivot axis, which can drive a single set of blades to achieve independent deflection. The deflection control of all vector blade units is completely decoupled and does not interfere with each other. In this invention, the vector control device is only located at the duct outlet end, and no guide vane structure is set at the duct inlet end, ensuring smooth and uninterrupted air intake in the duct and maximizing the lift efficiency of the duct fan. At the same time, the vector control device of this invention has a high fault tolerance rate. When any one of the blade units fails, the flight control system automatically shields the failed unit, recalculates the target deflection angle of the remaining 7 blade units, and compensates for the control force and torque of the failed unit through differential deflection, maintaining the stability of the aircraft attitude and achieving a safe emergency landing.

[0019] (2) The present invention provides a ducted circumferential distributed omnidirectional vector control system for an aircraft. The aircraft fuselage is arranged with a front ducted fan unit and a rear ducted fan unit along the longitudinal axis. The two ducted fan units are set with a fixed height difference in the vertical direction. The installation height of the front ducted fan unit is lower than that of the rear ducted fan unit. The distance between the centers of the front duct and the rear duct in the longitudinal axis direction of the fuselage is twice the diameter of the duct, which can effectively ensure that the center of gravity of the whole aircraft is located at the midpoint of the line connecting the centers of the two ducts.

[0020] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0022] Figure 1 This is a schematic diagram of the vector control device in the omnidirectional vector control system of a preferred embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the guide vane structure in a preferred embodiment of the present invention;

[0024] Figure 3This is a schematic diagram of the rotation angle of the guide vane in a preferred embodiment of the present invention; wherein: (a) is a schematic diagram of the guide vane rotating synchronously around the pivot axis; (b) is a schematic diagram of the independently adjustable deflectable flap section;

[0025] Figure 4 This is a schematic diagram of the structure of the longitudinally aligned, height-difference ducted twin-rotor aircraft of this invention;

[0026] Figure 5 This is a layout diagram of the ducted twin-rotor aircraft in this invention;

[0027] Figure 6 This is a schematic diagram of the ducted fan unit in this invention; wherein: (a) is a front view of the ducted fan unit; (b) is a three-dimensional structural view of the ducted fan unit;

[0028] Figure 7 This is a schematic diagram of the vector control device in this invention; wherein: (a) is a schematic diagram of the force principle of the guide vane; (b) is a schematic diagram of the resultant force of the X+ horizontal force of a single duct.

[0029] Figure 8 This is a schematic diagram of the pitch control structure of the longitudinally oriented, height-difference ducted twin-rotor aircraft in this invention;

[0030] Figure 9 This is a schematic diagram of the roll control structure of the longitudinally aligned, height-difference ducted twin-rotor aircraft in this invention; wherein: (a) is the right roll of the entire aircraft around the X-axis; (b) is the left roll of the entire aircraft around the X-axis;

[0031] Figure 10 This is a schematic diagram of the forward flight control structure of the longitudinally aligned, height-difference ducted twin-rotor aircraft in this invention;

[0032] Figure 11 This is a schematic diagram of the level flight control structure of the longitudinally aligned, height-difference ducted twin-rotor aircraft of the present invention; wherein: (a) is the level flight of the aircraft along the negative Y-axis; (b) is the level flight of the aircraft along the positive Y-axis;

[0033] In the figure, 1-first servo drive motor; 2-vector control device housing; 3-guide vane; 4-pivot shaft; 5-center hub; 6-fixed main wing section; 7-second servo drive motor; 8-bevel gear set; 9-deflectable flap section; 10-vector control device; 11-ducted fan unit; 13-ducted motor; 14-ducted fan; 15-fan unit housing. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent transformations or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0035] This invention provides a ducted circumferential distributed omnidirectional vector control system for an aircraft. The aircraft has a front duct and a rear duct arranged along its longitudinal axis. The omnidirectional vector control system includes two main modules: a vector control device 10 and ducted fan units 11 arranged with longitudinal height differences. The two modules cooperate to form a complete closed-loop technical solution, with the specific structure as follows:

[0036] Please see Figures 1 to 3 The vector control device 10 includes a front vector control device and a rear vector control device, which are respectively located at the outlet ends of the front and rear ducts. Each vector control device includes a vector control device housing 2, a central hub 5, and eight independently arranged vector blade units evenly distributed 360° around the duct. The central hub 5 is located at the center of the vector control device housing 2. The eight completely independent vector blade units completely cover the full flow section of the duct outlet. The pivot axis of each vector blade unit is arranged radially along the duct, the blade span is along the circumference of the duct, and the blade chord is along the axial direction of the duct. Specifically, each vector blade unit includes a first servo drive motor 1, a guide vane 3, and a pivot shaft 4. The first servo drive motor 1 is mounted on the inner wall of the vector control device housing 2. The output shaft of the first servo drive motor 1 is connected to one end of the pivot shaft 4, and the other end of the pivot shaft 4 is rotatably connected to the central hub 5. The pivot shaft 4 is arranged radially along the duct and passes through the guide vane 3, and the chord direction of the guide vane 3 is arranged axially along the duct. In this structure, each vector blade unit is equipped with an independent waterproof servo drive motor. The drive motor is fixed to the inner wall of the outer ring of the duct and the central hub. The output end is rigidly connected to the blade pivot shaft, which can drive a single blade to achieve independent deflection within the range of -25° to +25°. The deflection control of all blade units is completely decoupled and does not interfere with each other.

[0037] In one specific embodiment, the guide vane 3 adopts an aerospace-grade segmented flap-type variable camber structure and is divided into two parts along its airfoil chord: a fixed main wing section 6 at the front and a deflectable flap section 9. One end of the deflectable flap section 9 is pivotally connected to the trailing edge of the fixed main wing section 6. The fixed main wing section 6 occupies 65%~75% of the chord length, and the rear deflectable flap section 9 occupies 25%~35% of the chord length. Preferably, the fixed main wing section 6 occupies 70% of the chord length, and the deflectable flap section 9 occupies 30% of the chord length. The fixed main wing section 6 is rigidly connected to the pivot shaft 4 and serves as the main load-bearing structure of the guide vane 3, and can deflect as a whole with the pivot shaft 4. When the first servo drive motor 1 drives the pivot shaft 4 to rotate, the fixed main wing section 6 deflects with the pivot shaft 4, thereby realizing the angle of attack adjustment of the guide vane 3. Two miniature second servo drive motors 7 are integrated within the enclosed cavity of the fixed main wing section 6. Each second servo drive motor 7 is connected to a bevel gear set 8, which includes a meshing active bevel gear and a driven bevel gear. The active bevel gear is located on the output shaft of the second servo drive motor 7, and the driven bevel gear is located on the rotating shaft that is rotatably connected to the deflectable flap section 9 and the fixed main wing section 6. When the second servo drive motor 7 drives the active bevel gear to rotate, the active bevel gear rolls circumferentially along the tooth surface of the driven bevel gear, thereby driving the deflectable flap section 9 to achieve independent deflection within the range of -20° to +20° around the rotating shaft, thus continuously changing the airfoil camber. This, combined with the overall deflection of the guide vanes, achieves dual aerodynamic control of angle of attack and camber.

[0038] In one specific implementation, the rated operating angle range of the front duct vectoring blade unit is -18° to +18°, and the absolute limit protection angle is -25° to +25°. It adopts a high lift-to-drag ratio reference airfoil, emphasizing low-drag cruise and forward thrust output. The rated operating angle range of the rear duct vectoring blade unit is -22° to +22°, and the absolute limit protection angle is -25° to +25°. It adopts a high lift coefficient reference airfoil, emphasizing high torque attitude control and maneuvering flight compensation.

[0039] In one specific implementation, based on the connection and drive method of the segmented flap type continuous variable camber adaptive airfoil, the deflectable flap segment 9 can be hinged to the trailing edge of the fixed main airfoil segment 6 through a miniature precision titanium alloy rotating shaft. The second servo drive motor 7 in the closed cavity of the fixed main airfoil segment 6 drives the flap segment to achieve independent deflection within the range of -20° to +20°.

[0040] Please see Figures 4 to 10The ducted fan unit 11 includes a front ducted fan unit and a rear ducted fan unit respectively disposed within the front and rear ducts, and the front and rear ducted fan units are respectively disposed below the corresponding vector control devices; the front and rear ducted fan units have a fixed height difference in the vertical direction, and the installation height of the front ducted fan unit is lower than that of the rear ducted fan unit; each ducted fan unit includes a ducted motor 13, a ducted fan 14, and a fan unit housing 15, the ducted fan 14 being rotatably disposed within the fan unit housing 15, and the ducted motor 13 being connected to the ducted fan 14. Specifically, the height difference between the front and rear ducted fan units is 25-40% of the duct diameter; the distance between the centerlines of the front and rear ducts in the longitudinal axis direction of the fuselage is 1.8-2.5 times the duct diameter, ensuring that the center of gravity of the entire machine is located at the midpoint of the line connecting the centers of the two ducts.

[0041] In one specific embodiment, the vector control device housing 2 is integrally disposed with the corresponding fan unit housing 15, and the integrally disposed housing can be the corresponding duct.

[0042] Example 1

[0043] In this embodiment, the circumferential blade layout of the vector control device is as follows: Figure 1 As shown, the device has a diameter D = 2500 mm, a height H = 500 mm, and a central hub diameter of 200 mm. At the duct outlet end, eight sets of independent vector blade units are evenly arranged along the circumferential 360°, located at 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively, covering the four main axis directions of X+, Y+, X-, and Y-. The circumferential spacing between adjacent blade units is uniform, and there is no motion interference throughout the entire rotation range.

[0044] In this embodiment, the blade unit structural parameters of the vector control device are as follows: Figure 2 As shown, each vector blade unit adopts the NACA0012 symmetrical reference airfoil with a chord length of 70mm and a span of 430mm. The guide vane 3 adopts a sealed airfoil shell integrally formed from T700 carbon fiber, with a pre-reserved drive mechanism installation chamber inside. The shell wall thickness is 5mm, balancing structural strength and lightweight requirements. The pivot shaft 4 is a rotatable titanium alloy shaft with a diameter of 30mm. The pivot shaft 4 and the fixed main airfoil section 6 are rigidly locked together by a flat key, with no relative rotation. The inner end of the pivot shaft 4 is supported in the corresponding hole of the central hub 5 by a precision angular contact bearing, allowing free rotation. The outer end of the pivot shaft 4 is rigidly connected coaxially to the output shaft of the first servo drive motor 1, forming a complete rotary support and transmission link.

[0045] In this embodiment, the segmented flap-type continuous variable camber structure of the vector control device is implemented: each guide vane 3 is split along the chord direction into a fixed main wing section 6 at the front and a deflectable flap section 9 at the rear, which are connected by two sets of titanium alloy rotating shafts; when the first servo drive motor 1 drives the pivot shaft 4 to rotate, the fixed main wing section 6 deflects with the pivot shaft 4, thereby realizing the deflection of the guide vane 3. Two aerospace-grade miniature second servo drive motors 7 are built into the enclosed cavity of the fixed main wing section 6. Each second servo drive motor 7 is connected to the transmission mechanism of the bevel gear set 8. The fuselage of the second servo drive motor 7 is rigidly connected to the shell of the fixed main wing section 6. When the second servo drive motor 7 drives the active bevel gear in the bevel gear set 8 to rotate, the driven bevel gear cannot rotate because it is hinged and locked to the titanium alloy rotating shaft. The active bevel gear will roll circumferentially along the tooth surface of the driven bevel gear, thereby driving the deflectable flap section 9 to complete synchronous deflection around the rotating shaft. In this structure, the overall deflection of the guide vane 3 (main deflection) and the independent deflection of the deflectable flap section are coordinated to finally achieve precise closed-loop adjustment of the angle of attack of the guide vane 3.

[0046] In this embodiment, the rotation linkage control logic of the vector control device is as follows: Figure 3 As shown, the main deflection angle of the guide vane 3 and the camber angle of the flap achieve linkage compensation. The control logic is as follows: when the main deflection angle of the guide vane 3 is ≤10°, the angle of the deflectable flap section 9 can be independently adjusted within the range of -20° to +20°; when the main deflection angle of the guide vane 3 is >10°, the limit angle of the deflectable flap section 9 narrows linearly with the increase of the main deflection angle. When the main deflection angle reaches 25°, the flap angle is limited to the range of -10° to +10°. The airflow separation is suppressed by dynamic camber compensation to avoid airfoil stall.

[0047] The full-condition operation process of the vector control device in this embodiment is as follows:

[0048] 1. Stable hovering attitude: The flight control system adjusts the deflection angle of the guide vanes and the flap camber in the 8 vector blade units in real time based on the attitude sensor data, and outputs control force and torque in the corresponding direction to counteract external wind disturbances and maintain hovering stability; small attitude adjustments can be achieved by adjusting the flap camber only, without the need for the overall deflection of the guide vanes, resulting in faster response and lower power consumption.

[0049] 2. Omnidirectional translation control: such as Figure 7 As shown, when the vector control device needs to generate a forward (X+) resultant force, it controls the guide vanes at the 90° position to deflect positively, the guide vanes at the 180° position to deflect negatively, and the guide vanes at the 45° / 135° / 225° / 315° positions to deflect in pairs, canceling the Y-axis force component and superimposing the X-axis force component to form a pure forward horizontal resultant force. A single duct can achieve 360° arbitrary direction translation without attitude. Figure 7 (a) and Figure 7In (b), Fa represents the total aerodynamic force acting on the guide vane; Fz represents the axial lift component of the total aerodynamic force; Fx represents the horizontal control force component of the total aerodynamic force; and the high-speed axial airflow is the high-speed axial airflow discharged by the ducted fan.

[0050] 3. High maneuverability: The guide vanes deflect to the target angle of attack, while the flaps deflect downwards to form a positive camber airfoil, which increases the lift coefficient and suppresses airflow separation. There is no stall at an equivalent angle of attack of 25°, and the maximum control torque is output to meet the requirements of high-speed maneuverability.

[0051] 4. Fault-tolerant operation: When any one set of blade units fails, the flight control system automatically shields the failed unit, recalculates the target deflection angle of the remaining 7 sets of blades, and compensates for the control force and torque of the failed unit through differential deflection to maintain the stability of the aircraft attitude and achieve a safe emergency landing.

[0052] The overall layout of the longitudinally aligned, height-difference ducted twin-rotor rotor in this embodiment is as follows: Figure 4 and 5 As shown, the aircraft adopts a tandem dual-duct layout, with a fuselage length of 8000mm and a width of 3000mm. A front duct and a rear duct are arranged along the X-axis, with a longitudinal distance of 2500mm between the centers of the two ducts. The aircraft's center of gravity is located at the midpoint of the line connecting the centers of the two ducts. The front duct is installed at a lower height than the rear duct, with a vertical height difference of 900mm, ensuring that the wake of the front duct completely avoids the air intake of the rear duct, thus completely eliminating aerodynamic interference. Both the front and rear ducts utilize the vector control device of this embodiment. The rated operating angle range of the front duct blades is -18° to +18°, and the rated operating angle range of the rear duct blades is -22° to +22°.

[0053] The full-condition control logic for the longitudinally aligned, height-difference ducted twin-rotor aircraft in this embodiment is as follows:

[0054] 1. Vertical takeoff and landing and hovering: The front and rear ducted propellers accelerate synchronously to provide lift for the whole machine; the differential deflection of the vector blade unit at the outlet end achieves hovering attitude stability and omnidirectional translation in place, and the attitude control and altitude control are completely decoupled, with no altitude fluctuation.

[0055] 2. Pitch control: such as Figure 8 As shown, when the nose is downward, the front duct generates a horizontal resultant force F to the rear (X-), and the rear duct generates a horizontal resultant force F to the front (X+), forming a pitching moment M around the Y-axis. The magnitudes of the front and rear horizontal resultant forces are equal, there is no translational disturbance, and there is no need to change the lift difference between the front and rear ducts, and there is no height coupling; conversely, an upward pitching moment is generated.

[0056] 3. Roll control: such as Figure 9As shown, when the fuselage rolls to the right, the front duct generates a horizontal resultant force F to the left (Y-), and the rear duct generates a horizontal resultant force F to the right (Y+), forming a right rolling moment around the X-axis. The magnitudes of the front and rear horizontal resultant forces are equal, there is no translational disturbance, the front and rear ducts move synchronously, and there is no pitch coupling; conversely, a left rolling moment is generated.

[0057] 4. Forward cruise: such as Figure 10 As shown, the guide vanes in the front and rear ducts deflect synchronously, generating forward thrust to propel the aircraft forward. This allows the aircraft to maintain a level flight attitude without needing to pitch up, significantly reducing forward drag. At the same time, the front duct flaps are adjusted to the 0° neutral position to form a symmetrical airfoil, reducing drag. The rear duct flaps adaptively adjust their camber to compensate for the wake effect, thus enhancing flight efficiency.

[0058] 5. Level flight cruise: such as Figure 11 As shown, the guide vanes in the front and rear ducts are locked at preset operating angles of attack, generating constant lift and cruise thrust to balance the aircraft's own weight and flight drag, maintaining the fuselage's horizontal attitude without pitch or roll deviation, achieving a constant level flight attitude throughout the entire flight, and completely eliminating the additional flight drag caused by attitude fluctuations. At the same time, the deflectable flap section 9 of each guide vane in the front duct is adjusted to an optimized position to match the incoming flow, forming a stable and smooth inlet airflow field to ensure stable lift output. The deflectable flap section 9 of each guide vane in the rear duct adaptively and dynamically adjusts its camber and deflection angle to compensate for the wake interference of the front duct and external airflow disturbances, and to counteract the attitude deviation trend, thus significantly enhancing flight stability and endurance efficiency during the level flight phase.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A ducted circumferential distributed omnidirectional vector control system for an aircraft, wherein the aircraft has a front duct and a rear duct arranged along its longitudinal axis, characterized in that, The omnidirectional vector control system includes a front vector control device, a rear vector control device, a front duct fan unit, and a rear duct fan unit. The front vector control device and the rear vector control device are respectively located at the outlet ends of the front duct and the rear duct. Each vector control device includes a vector control device housing (2), a central hub (5), and multiple independently arranged vector blade units. The central hub (5) is located at the center of the vector control device housing (2). Each vector blade unit includes a first servo drive motor (1), a guide vane (3), and a pivot shaft (4). The first servo drive motor (1) is located on the inner wall of the vector control device housing (2). The output shaft of the first servo drive motor (1) is connected to one end of the pivot shaft (4), and the other end of the pivot shaft (4) is rotatably connected to the central hub (5). The rotating shaft (4) is arranged radially along the duct and passes through the guide vane (3), and the chord direction of the guide vane (3) is arranged along the duct axis; each guide vane (3) can deflect independently under the drive of its first servo drive motor (1); the front duct fan unit and the rear duct fan unit are respectively arranged in the front duct and the rear duct, and below the corresponding vector control device; the front duct fan unit and the rear duct fan unit have a fixed height difference in the duct axis direction, and the installation height of the front duct fan unit is lower than the installation height of the rear duct fan unit; each duct fan unit includes a duct motor (13), a duct fan (14) and a fan unit housing (15), the duct motor (13) is connected to the duct fan (14) and is used to drive the duct fan (14) to rotate in the fan unit housing (15).

2. The omnidirectional vector control system according to claim 1, characterized in that, The guide vane (3) adopts a segmented flap-type variable camber structure and is divided into two parts along its airfoil chord direction, including a fixed main airfoil section (6) and a deflectable flap section (9). The fixed main airfoil section (6) is rigidly connected to the pivot shaft (4) and can deflect as a whole with the pivot shaft (4). One end of the deflectable flap section (9) is pivotally connected to the trailing edge of the fixed main airfoil section (6). A second servo drive motor (7) and a bevel gear set (8) are provided in the cavity of the fixed main airfoil section (6). The second servo drive motor (7) is connected to the bevel gear set (8) for transmission to drive the deflectable flap section (9) to deflect independently, thereby continuously changing the airfoil camber.

3. The omnidirectional vector control system according to claim 2, characterized in that, The bevel gear set (8) includes a driving bevel gear and a driven bevel gear that mesh with each other. The driving bevel gear is set on the output shaft of the second servo drive motor (7), and the driven bevel gear is set on the rotating shaft that rotatably connects the deflectable flap section (9) and the fixed main wing section (6). When the first servo drive motor (1) drives the pivot shaft (4) to rotate, the guide vane (3) deflects with the pivot shaft (4), thereby realizing the angle of attack adjustment. When the second servo drive motor (7) drives the driving bevel gear to rotate, the driving bevel gear rolls circumferentially along the tooth surface of the driven bevel gear, thereby driving the deflectable flap section (9) to deflect synchronously around the rotating shaft.

4. The omnidirectional vector control system according to claim 3, characterized in that, The second servo drive motor (7) is a micro servo drive motor; two second servo drive motors (7) are provided in the cavity of the fixed main wing section (6), respectively located at both ends of the cavity of the fixed main wing section (6), and each second servo drive motor (7) is connected to a bevel gear set (8).

5. The omnidirectional vector control system according to claim 3, characterized in that, The deflection range of the guide vane (3) is -25° to +25°; the deflection range of the deflectable flap section (9) is -20° to +20°.

6. The omnidirectional vector control system according to claim 5, characterized in that, The guide vane (3) in the front vector control device adopts a high lift-to-drag ratio reference airfoil, with a rated working angle range of -18° to +18° and an absolute limit protection angle of -25° to +25°; the guide vane (3) in the rear vector control device adopts a high lift coefficient reference airfoil, with a rated working angle range of -22° to +22° and an absolute limit protection angle of -25° to +25°.

7. The omnidirectional vector control system according to claim 2, characterized in that, Each of the vector control devices includes 8 sets of the vector blade units; the fixed main wing section (6) occupies 65% to 75% of the chord length, and the rear deflectable flap section (9) occupies 25% to 35% of the chord length.

8. The omnidirectional vector control system according to claim 1, characterized in that, The height difference between the front duct fan unit and the rear duct fan unit is 25-40% of the duct diameter; the distance between the centerlines of the front duct and the rear duct in the longitudinal axis of the fuselage is 1.8-2.5 times the duct diameter.

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