A vertical take-off and landing compound helicopter and method of controlling the same

Abstract

This invention discloses a vertical takeoff and landing (VTOL) autogyro aircraft and its control method. The aircraft includes a fuselage, a rotor mechanism, a rotor drive system, a ducted fan propulsion system, a control stick, landing gear, and a vectoring nozzle. The rotor drive system consists of two motors rotating in opposite directions, driving the rotor through a parallel gear assembly, and a controller is provided to coordinate the control of rotational speed and torque. Both the drive shaft and the column are equipped with universal joints, and the centers of the rotating shafts coincide. The ducted fan propulsion system can adjust the vertical jet propulsion; the vectoring nozzle can adjust the horizontal jet propulsion. Control method: During vertical takeoff, the rotor drive system provides lift; after reaching a certain altitude, the ducted fan propulsion system provides forward propulsion; after reaching a predetermined forward speed, the rotor drive system is shut down, switching to autogyro mode, where the ducted fan propulsion system maintains altitude and forward speed; during landing, the rotor drive is restored, and the aircraft descends gradually. This invention combines the high safety of VTOL, hovering, and autogyro aircraft.

Description

Technical Field

[0001] This invention relates to the field of autogyro technology, specifically a vertical takeoff and landing autogyro and its control method. Background Technology

[0002] In congested urban environments, aircraft takeoff and landing face numerous limitations. Currently, helicopters are the primary aircraft capable of vertical takeoff and landing in confined spaces such as rooftops, parks, and roads. However, their complex structures and high safety dependence on component reliability and operator skill result in high purchase, operation, and maintenance costs, hindering widespread adoption. While multi-rotor aircraft possess vertical takeoff and landing capabilities, their safety relies on redundant configurations of highly reliable components, leading to high costs and limiting their application to limited areas such as unmanned cargo transport. Existing patent CN109466751 provides a vertical takeoff and landing rotorcraft solution, but its complex structure due to the numerous pitch control mechanisms and high operator skill requirements prevent it from achieving the widespread demand for low-cost, easy-to-operate, and highly safe aircraft.

[0003] Therefore, there is an urgent need to develop a vertical take-off and landing (VTOL) autogyro that is inherently safe to solve the problems in existing technologies. Summary of the Invention

[0004] The present invention provides a vertical takeoff and landing autogyro aircraft, comprising: fuselage, column, rotor mechanism, rotor drive system, ducted fan propulsion system, control stick, landing gear, connecting rod and vector nozzle.

[0005] One end of the column is fixedly connected to the fuselage, and the other end is fixed with the rotor mechanism.

[0006] The operating lever is connected to the column.

[0007] The rotor drive system is fixedly connected to the fuselage and is used to drive the rotor to rotate. The rotor drive system includes: a first motor mechanism, a second motor mechanism, a parallel gear assembly, a reducer, an overrunning clutch, a drive shaft, a motor driver, and a controller. The first motor mechanism includes a motor and a pinion gear, with the motor's output end fixedly connected to the pinion gear. The second motor mechanism has the same structure as the first motor mechanism. The first and second motor mechanisms rotate in opposite directions, and the two motors have identical mechanical and electromagnetic characteristics.

[0008] The ducted fan propulsion system is connected to the tail of the fuselage via a connecting rod, which is fixedly connected to the tail of the fuselage. The ducted fan propulsion system is rotatably connected to the connecting rod. The vector nozzle inlet is connected to the exhaust outlet of the ducted fan propulsion system.

[0009] The present invention also provides a control system for the aforementioned rotor drive system, comprising a first driver, a second driver, and a controller. The controller coordinates the control of the first driver and the second driver. The first driver controls and monitors the speed, voltage, and current of the first motor; the second driver controls and monitors the speed, voltage, and current of the second motor. The first driver ensures that the rotor drive output speed conforms to the set value; the second driver ensures that the output torque of the first motor and the second motor remains consistent.

[0010] Furthermore, the drive shaft is divided into a front part and a rear part. The front part is fixedly connected to the rotor drive, and the rear part is fixedly connected to the rotor mechanism. The front part and the rear part are connected by a universal joint.

[0011] Furthermore, the column is divided into a lower part and an upper part. The lower part is fixed to the fuselage, and the upper part is connected to the rotor mechanism through a bearing. The upper and lower parts are connected by a universal joint. The center of the universal joint shaft of the column coincides with the center of the universal joint shaft of the drive shaft.

[0012] Furthermore, the ducted propulsion system can be vertically adjusted relative to the fuselage on the connecting rod to perform longitudinal trim and pitch control.

[0013] Furthermore, vectoring nozzles can adjust the horizontal direction of the ducted fan's exhaust, enabling heading maintenance and regulation.

[0014] The present invention also provides a control method for the above-mentioned aircraft, comprising the following steps: 1. Takeoff phase: Adjust the propeller disk to the trim position to obtain the maximum lift component. 2: Start the rotor drive system and propulsion system to gradually accelerate the rotor; 3. When the lift generated by the rotor speed exceeds the weight of the fuselage, the aircraft takes off. At the moment of takeoff, adjust the rotor disk pitch angle to balance the fuselage; adjust the ducted fan power to balance the thrust component generated by the rotor lift, keeping the fuselage longitudinally stationary. Takeoff trim is complete. 4): During vertical ascent, if it is necessary to change or maintain the heading, the jet direction of the vector nozzle is adjusted to generate a horizontal deflection force, causing the fuselage to deflect or maintain the heading. 5: Increasing rotor speed increases lift, allowing the fuselage to rise vertically; 6: After the fuselage ascends vertically to the preset height, the propulsion system power is increased to propel the fuselage forward; 7: As the forward speed gradually increases, adjust the pitch angle of the propeller disk relative to the fuselage in sync; 8: Adjust the rotor drive system power synchronously according to the forward flight speed to maintain the rotor speed within the corresponding range: When maintaining altitude, the forward flight speed and rotor speed are inversely proportional within a certain range; during the hovering phase, the forward flight speed is zero, and the required rotor speed is the highest; when the forward flight speed reaches the maximum value for maintaining that altitude, the rotor speed is the lowest. 9: When the current airspeed reaches the minimum value for maintaining this altitude, the rotor drive system is shut down; the aircraft enters a fully autorotating rotor state, maintaining altitude and forward speed through the propulsion system; 10: When landing is required, gradually reduce the power of the propulsion system and decrease the forward speed and altitude; 11: When the plane reaches the vicinity of the predetermined landing point and the altitude is within the preset range, the propulsion system power will be reduced to the minimum forward speed required to maintain that altitude. 12: Activate the rotor drive system, maintain the required rotor speed to maintain altitude based on the current forward speed, gradually increase the power of the rotor drive system and decrease the power of the propulsion system to maintain the fuselage at the required forward speed; 13: When the current airspeed drops to zero and the rotor speed reaches the maximum value for maintaining this altitude, the aircraft is in a hovering state; 14: Gradually reduce the power of the rotor drive system, reduce the rotor speed, and lower the altitude of the aircraft. Simultaneously adjust the power of the propulsion system so that the force generated by the propulsion system can balance the backward force generated by the rotor, and keep the fuselage in a horizontal and stationary state. 15: The rate at which the rotor speed decreases determines the aircraft's descent rate; 16: When approaching the landing point, appropriately increase the rotor speed to minimize the aircraft's descent rate; 17: After contact with the ground, continue to reduce the power of the rotor drive system, and the rotor speed will continue to decrease until it stops rotating.

[0015] Compared with existing technologies, the advantages of this invention are: by using a rotor drive without counter-torque, combined with a ducted fan and a vector nozzle, vertical take-off and landing of the autogyro is achieved; on the other hand, the two independent drive sources provide redundancy for the safety of the aircraft, making it safer; it not only reduces manufacturing costs, but also makes it easier for ordinary people to purchase and drive. Attached Figure Description

[0016] Figure 1 This is a front-view perspective view of an overall structure in an embodiment of the present invention; Figure 2 This is a rear-view perspective view of an overall structure in an embodiment of the present invention; Figure 3 This is a side cross-sectional view of the column, rotor assembly, and drive shaft in an embodiment of the present invention; Figure 4This is a structural diagram of the rotor drive system in an embodiment of the present invention; Figure 5 This is a graph showing the relationship between forward flight speed and rotor speed in this embodiment of the invention (the horizontal axis represents forward flight speed, and the vertical axis represents rotor speed).

[0017] The figures are labeled as follows: 1. Fuselage; 2. Column; 3. Rotor mechanism; 4. Rotor drive system; 42. First motor mechanism; 421. Motor; 422. Pinion; 43. Second motor mechanism; 44. Parallel gear assembly; 45. Reducer; 46. Overrunning clutch; 47. Drive shaft; 5. Ducted fan propulsion system; 6. Control stick; 7. Landing gear; 8. Connecting rod; 9. Vectoring nozzle. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figure 1 and Figure 2 As shown in the figure, the vertical takeoff and landing autogyro aircraft provided in this embodiment includes: fuselage 1, column 2, rotor mechanism 3, rotor drive system 4, ducted fan propulsion system 5, control stick 6, landing gear 7, connecting rod 8, and vector nozzle 9.

[0020] The tail of fuselage 1 is rotatably connected to a ducted fan propulsion system 5 via a connecting rod 8. The connecting rod 8 is fixedly connected to the tail of fuselage 1. The control lever 6 is hinged to the column 2. The landing gear 7 is fixedly installed at the bottom of fuselage 1.

[0021] like Figure 1 , Figure 2 and Figure 3 As shown, one end of the column 2 is fixedly connected to the fuselage 1, and the other end is fixedly connected to the rotor mechanism 3. The rotor drive system 4 is fixedly connected to the fuselage 1 and is connected to the rotor mechanism 3 via a drive shaft 47.

[0022] like Figure 3 and Figure 4As shown, the rotor drive system 4 includes: a first motor mechanism 42, a second motor mechanism 43, a parallel gear assembly 44, a reducer 45, an overrunning clutch 46, a drive shaft 47, a motor driver, and a controller. The first motor mechanism 42 includes a motor 421 and a pinion 422. The output end of the motor 421 is fixedly connected to the pinion 422. The structure of the second motor mechanism 43 is the same as that of the first motor mechanism 42. The rotation directions of the first motor mechanism 42 and the second motor mechanism 43 are opposite. The mechanical and electromagnetic characteristics of the two motors 421 are identical.

[0023] The parallel gear assembly 44 meshes with two pinions 422 respectively. The output end of the parallel gear assembly 44 is connected in sequence to the reducer 45, the overrunning clutch 46 and the drive shaft 47. The motor driver is electrically connected to the motor 421 and the controller respectively.

[0024] like Figure 3 As shown, the drive shaft 47 is divided into a front part and a rear part. The front part is fixedly connected to the output end of the reducer 45 or the overrunning clutch 46, and the rear part is fixedly connected to the rotor hub of the rotor mechanism 3. The front and rear parts are connected by a universal joint.

[0025] The column 2 is divided into a lower part and an upper part. The lower part is fixedly connected to the fuselage 1, and the upper part is connected to the rotor hub shell of the rotor mechanism 3 through a bearing. The upper and lower parts are connected by a universal joint. The center of the universal joint shaft of the column 2 coincides with the center of the universal joint shaft of the drive shaft 47.

[0026] The ducted fan propulsion system 5 can be vertically rotated relative to the fuselage 1 via the connecting rod 8 for longitudinal trim and pitch control.

[0027] The air inlet of the vector nozzle 9 is connected to the exhaust port of the ducted fan propulsion system 5; the nozzle of the vector nozzle 9 can swing left and right for heading control.

[0028] In a vertical takeoff and landing (VTOL) autogyro, the rotor speed is maintained by continuously outputting torque to the rotor via a rotor drive system during the VTOL and hovering phases. At this time, the rotor functions as a "rotating wing," generating lift by displacing air downwards and consuming power. To balance the entire weight (W) of the aircraft, the hovering lift formula is used:

[0029] W: Aircraft weight · air density • A: Rotor disk area •C_T: Tensile coefficient · Rotor angular velocity during hovering (rad / s) For a rotorcraft, the rotor dimensions are fixed, meaning the rotor disk area A is fixed, and the air density is fixed. It is also certain that weight is directly proportional to rotational speed (angular velocity); Once level flight is achieved, the rotor drive is discontinued, allowing it to enter autorotation mode. At this point, the rotor's rotation no longer depends on the rotor drive system but is propelled by the airflow ahead. To maintain stable autorotation, the rotor disk pitch angle must be maintained, along with a suitable forward speed.

[0030] During level flight, the actual rotational speed (RPM) of the rotor is lower than when hovering. This is because: The lift generated by the rotor depends on the "relative airflow velocity"; The lift generated by an airfoil is proportional to the square of the resultant velocity of the relative airflow. This resultant velocity is composed of two superimposed parts: • Rotational tangential speed: determined by rotor speed Decide • Forward axial velocity: determined by the aircraft's level flight speed (V); When hovering, the forward velocity V=0, and the resultant velocity comes entirely from rotation. In order to generate enough lift to balance the weight, the rotor must be rotated to a very high speed.

[0031] During level flight, the forward velocity V is very large, which is superimposed on the rotational velocity. For any point on the rotor blade, the resultant velocity is the vector sum of the rotational velocity and the forward velocity. Even if the rotor speed decreases, the actual resultant velocity of the blade profile may not be low, and may even be higher (especially for the advancing blade), due to the contribution of the forward velocity. Therefore, the same or even greater lift can be generated with only a lower rotational speed.

[0032] According to research, the rotor speed of a conventional autogyro does not change significantly with its forward flight speed.

[0033] • The rotor speed in level flight mode can be reduced to 60%-75% of that in hover mode, which is a reduction of 25%-40%.

[0034] A simple example: Assuming a rotor radius R = 4m, the rotor tip needs a resultant velocity of 200m / s to generate sufficient lift when hovering.

[0035] • Hovering: Forward speed = 0, so the rotor must provide the full 200m / s tangential speed → Rotation speed = 200 / (R*2*3.14157) = 200 / 25.13 = 7.959 rpm = 477.5 RPM.

[0036] • Level flight: Forward speed = 50 m / s (180 km / h, cruise speed). At this time, the resultant velocity of the propeller tip = the vector sum of the rotational speed and the forward speed (on the advancing side, both are in the same direction). To achieve a resultant velocity of 200 m / s, the rotational speed only needs to provide about 150 m / s. Rotational speed = 150 / (R * 2 * 3.14157) = 150 / 25.13 = 7.959 rpm = 358.1 RPM. The rotational speed can be reduced by 25%.

[0037] There's also the contribution of the "disk angle of attack": during level flight, the rotor pitches back. This pitch angle creates an upward component of the incoming airflow (forward velocity) that passes perpendicularly through the rotor disk. This upward airflow component further aids in lift generation, effectively increasing the blade's effective angle of attack. Therefore, even at lower speeds, lift can be generated efficiently.

[0038] Conversely, the same principle applies to transitioning from level flight to vertical flight; it requires establishing a curve for the rotor speed versus forward speed (including pitch angle) for each aircraft. However, the approximate curve is as follows: Figure 5 As shown It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0039] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A vertical takeoff and landing (VTOL) autogyro, comprising: The fuselage (1), column (2), rotor mechanism (3), rotor drive system (4), ducted fan propulsion system (5), control stick (6), landing gear (7), connecting rod (8) and vector nozzle (9); The feature is that: one end of the column (2) is fixedly connected to the fuselage (1), and the other end is fixed with the rotor mechanism (3); The rotor drive system (4) is fixedly connected to the fuselage; The operating lever (6) is hinged to the column (2); The ducted fan propulsion system (5) is connected to the tail of the fuselage (1) via the connecting rod (8), and the ducted fan propulsion system (5) is rotatably connected to the connecting rod (8); The air inlet of the vector nozzle (9) is connected to the exhaust port of the ducted fan propulsion system (5).

2. The rotor drive system according to claim 1, characterized in that: The rotor drive system (4) includes: a first motor mechanism (42), a second motor mechanism (43), a parallel gear assembly (44), a reducer (45), an overrunning clutch (46), a transmission shaft (47), a motor driver, a controller, etc.; the first motor mechanism (42) includes: the motor (421) and the pinion (422); the output end of the motor (421) is fixedly connected to the pinion (422); the structure of the second motor mechanism (43) is the same as that of the first motor mechanism (42); the rotation directions of the first motor mechanism (42) and the second motor mechanism (43) are opposite; the mechanical and electromagnetic characteristics of the two motors (421) are the same.

3. A control system for the rotor drive system of claim 2, characterized in that: The control system includes a first driver, a second driver, and a controller; the controller controls and coordinates the first driver and the second driver; the first driver controls and monitors the speed, voltage, and current of the first motor; the second driver controls and monitors the speed, voltage, and current of the second motor; the first driver ensures that the output speed of the rotor drive system conforms to the set value; the second driver ensures that the output torque of the first motor and the second motor remains consistent.

4. The rotor drive system (4) according to claims 2 and 3, characterized in that: The drive shaft (47) is divided into a front part and a rear part. The front part is fixedly connected to the rotor drive, and the rear part is fixedly connected to the rotor mechanism (3). The front part and the rear part are connected by a universal joint.

5. The column (2) according to claim 1, characterized in that: The column has two parts. Composition: lower part and upper part, the lower part is fixed to the fuselage (1), the upper part is connected to the rotor mechanism (3) through bearings; the upper part and the lower part are connected by universal joints; the universal joint shaft center of the column (2) coincides with the universal joint shaft center of the drive shaft (47).

6. A vertical takeoff and landing autogyro aircraft according to claim 1, characterized in that: The ducted fan propulsion system (5) can be vertically adjusted relative to the fuselage (1) on the connecting rod (8) to perform longitudinal trim and pitch control.

7. A vertical takeoff and landing autogyro aircraft according to claim 1, characterized in that: The vector nozzle (9) can adjust the horizontal direction of the jet propulsion of the ducted fan propulsion system (5) to maintain and adjust the heading.

8. A control method for a vertical takeoff and landing (VTOL) autogyro aircraft, characterized in that: Includes the following steps: 1) Takeoff phase: Adjust the propeller disk to the trim position to obtain the maximum lift component; 2): Start the rotor drive system and propulsion system to gradually accelerate the rotor; 3) When the lift generated by the rotor speed exceeds the weight of the fuselage, the aircraft takes off. At the moment of takeoff, adjust the rotor disk pitch angle to balance the fuselage; adjust the ducted fan power to balance the thrust component generated by the rotor lift, keeping the fuselage longitudinally stationary. Takeoff trim is complete. 4): During vertical ascent, if it is necessary to change or maintain the heading, the jet direction of the vector nozzle is adjusted to generate a horizontal deflection force, causing the fuselage to deflect or maintain the heading. 5): Increasing the rotor speed increases lift, allowing the fuselage to rise vertically; 6): After the fuselage ascends vertically to the preset height, the propulsion system power is increased to propel the fuselage forward; 7): As the forward speed gradually increases, adjust the pitch angle of the propeller disk relative to the fuselage in sync; 8): Based on the forward flight speed, synchronously adjust the power of the rotor drive system to maintain the rotor speed within the corresponding range: When maintaining altitude, the forward flight speed and rotor speed are inversely proportional within a certain range; during the hovering phase, the forward flight speed is zero, and the required rotor speed is the highest; when the forward flight speed reaches the maximum value for maintaining that altitude, the rotor speed is the lowest. 9): When the current airspeed reaches the minimum value for maintaining this altitude, the rotor drive system is shut down; the aircraft enters a fully autorotating rotor state, maintaining altitude and forward airspeed through the propulsion system; 10): When landing is required, gradually reduce the power of the propulsion system and decrease the forward speed and altitude; 11): When the plane reaches the vicinity of the predetermined landing point and the altitude is within the preset range, the propulsion system power will be reduced to the minimum forward speed required to maintain that altitude. 12): Activate the rotor drive system, maintain the required rotor speed to maintain altitude based on the current forward speed, gradually increase the power of the rotor drive system and decrease the power of the propulsion system to maintain the fuselage at the required forward speed; 13): When the current airspeed drops to zero and the rotor speed reaches the maximum value for maintaining this altitude, the aircraft is in a hovering state; 14): Gradually reduce the power of the rotor drive system, reduce the rotor speed, and lower the altitude of the aircraft. Simultaneously adjust the power of the propulsion system so that the force generated by the propulsion system can balance the backward force generated by the rotor, and keep the fuselage in a horizontal and stationary state. 15): The rate at which the rotor speed decreases determines the descent rate of the aircraft; 16): When approaching the landing point, appropriately increase the rotor speed to minimize the aircraft's descent rate; 17): After contact with the ground, continue to reduce the power of the rotor drive system, and the rotor speed continues to decrease until it stops rotating.

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