Micro-miniature semi-tilting unmanned aerial vehicle and control method thereof

Abstract

The invention provides a micro-miniature semi-tilting unmanned aerial vehicle and a control method thereof.The unmanned aerial vehicle comprises a main body structure, a coaxial double-paddle system, a tilting double-rotor system, a full-motion control surface assembly, a flight control system and a power supply assembly; the main body structure is composed of a carbon fiber carbon plate, a carbon tube and a 3D printing photosensitive resin part, and light weight and rigid supporting are achieved; the coaxial double-propeller system provides main lift force and counteracts reverse torsional moment; the double-rotor system is tilted, and a lift force / thrust mode is switched; the pneumatic efficiency of the tilting rotor wing is improved by the full-motion control surface assembly; the control method comprises a low-speed mode and a high-speed forward flight mode, the vertical take-off and landing, hovering and high-speed cruising are integrated, the structure is simplified, the stability is improved, and the cost is low.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, specifically to a micro-sized semi-tilt UAV and its control method. Background Technology

[0002] With the continuous expansion of the application fields of drones, they are widely used in military and civilian fields such as modern agriculture, geological exploration, and counter-terrorism operations. However, different types of rotorcraft have functional shortcomings and cannot meet the comprehensive needs of multiple scenarios: fixed-wing aircraft cannot take off and land vertically, have high requirements for ground space and no hovering ability, and cannot perform fixed-point tasks such as fire fighting; conventional layout helicopters can take off and land vertically and hover, but they do not have high-speed flight capabilities, and their swashplate structure is complex and maintenance costs are high; conventional multi-rotor aircraft have poor aerodynamic efficiency, weak maneuverability, and small internal space, making them unable to complete long-term transportation and long-distance supply missions.

[0003] Among existing similar technical solutions, coaxial UAVs use two sets of counter-rotating rotors on the same main shaft to cancel out the anti-torque, but they require a complex pitch control system and rotor hub structure. The rotor hub needs to precisely support the two sets of rotors on the main shaft, withstand centrifugal force, torque and alternating stress, and also needs to integrate high-precision hinge joints. The pitch control system converts the control commands into changes in blade angle through linkages and rocker arm mechanisms, which is complex and prone to failure. Tiltrotor UAVs integrate the advantages of helicopters and fixed-wing aircraft, but they require complex linkage mechanisms to achieve rotor periodic pitch and collective pitch adjustment. The synchronous control of "rotor tilt + blade pitch adjustment" has high requirements, and timing deviations can easily cause vibration or dynamic imbalance. Moreover, there is an aerodynamic coupling effect when the rotor switches between hovering vortices and high-speed airflow, resulting in poor mode transition stability.

[0004] Therefore, there is an urgent need for a micro-sized unmanned aerial vehicle (UAV) solution that can take off and land vertically, hover, and cruise at high speed, while also having a simplified structure and reliable control. Summary of the Invention

[0005] This invention provides a micro-sized semi-tilt unmanned aerial vehicle and its control method, aiming to solve the problems mentioned in the background art.

[0006] This invention is implemented as follows: a micro-sized semi-tilt unmanned aerial vehicle (UAV) includes a main structure, a coaxial dual-propeller system, a tilt-rotor system, an all-moving control surface assembly, a flight control system, and a power supply assembly. The main structure includes an outer shell, landing gear, reinforcing carbon rods, a bottom carbon plate, a middle carbon plate, a rear carbon plate, a fuselage connecting carbon tube, a front carbon tube fixing assembly, and a rear carbon tube fixing assembly. The outer shell is made of photosensitive resin and is manufactured by 3D printing, wrapping the front of the fuselage to provide a flow-rectifying and drag-reducing effect. The landing gear, reinforcing carbon rods, bottom carbon plate, middle carbon plate, and rear carbon plate are all made of carbon fiber. The bottom carbon plate is mounted on the landing gear, the middle carbon plate is located above the bottom carbon plate, and the rear carbon plate is located at the tail of the fuselage. The fuselage is equipped with three carbon tubes; the front of the carbon tubes is fixed to the middle carbon plate via a front fixing assembly, and the rear of the carbon tubes is fixed to the rear carbon plate via a rear fixing assembly. Both the front and rear fixing assemblies are made of photosensitive resin and are 3D printed. The coaxial dual-rotor system includes a coaxial upper rotor, a coaxial lower rotor, and a coaxial motor. The coaxial motor consists of two independently controlled brushless motors mounted on the middle carbon plate. The coaxial upper rotor is located above the coaxial motor and rotates clockwise, while the coaxial lower rotor is located below the coaxial motor and rotates counterclockwise. The coaxial dual-rotor system provides the main lift for the UAV and counteracts the rotor's anti-torque. The tilt-rotor system includes a left tilt motor. The system comprises a right tilt motor, a left tilt rotor, a right tilt rotor, a left tilt servo, a right tilt servo, a tilt motor base, a carbon fiber tilt shaft, and a bearing base. The bearing base is mounted on the rear carbon plate and contains four ball bearings. The carbon fiber tilt shaft passes through the bearing base and is freely rotatable; its two sides are fixed to the all-moving control surface assembly, and its two ends are fixed to the tilt motor base. The left and right tilt motors are mounted on the two side tilt motor bases and are both three-phase brushless motors. The left and right tilt rotors are connected to the output ends of the left and right tilt motors, respectively. The left and right tilt servos are mounted on the rear carbon plate, and their output ends are each connected to a servo rocker arm. The servo arm is connected to the all-moving control surface assembly via bolts to drive the carbon fiber tilt shaft, which in turn drives the tilt motor and tilt rotor. The all-moving control surface assembly includes a left all-moving control surface and a right all-moving control surface, both made of photosensitive resin and manufactured by 3D printing. It is positioned below the wake of the tilt rotor to improve its aerodynamic efficiency. The flight control system is integrated into the flight tower, which is mounted on the middle carbon plate via shock-absorbing studs. It includes a flight controller and an electronic speed controller for controlling the operation of the coaxial motor, left tilt motor, right tilt motor, left tilt servo, and right tilt servo. The power supply component is a 2200mAh lithium battery, which is fixed to the bottom carbon plate with nylon clips to power the various electrical components of the UAV.

[0007] Preferably, the maximum tilt angle of the tilt rotor driven by the left tilt servo and the right tilt servo is ≤60°.

[0008] Preferably, the landing gear is manufactured using CNC cutting technology, and the bottom carbon plate, middle carbon plate, and rear carbon plate are all manufactured using CNC cutting technology.

[0009] Preferably, the rotational speeds of the coaxial upper rotor and coaxial lower rotor are independently adjusted by the flight controller to achieve yaw control of the UAV.

[0010] Preferably, the rotational speeds of the left tilt rotor and the right tilt rotor are independently adjusted by the flight controller to achieve roll control of the UAV.

[0011] Preferably, the speed difference between the coaxial dual-propeller system and the tilt-rotor system is adjusted by the flight controller to achieve pitch control of the UAV.

[0012] The control method for the micro-sized semi-tilt UAV includes two modes: low-speed mode control and high-speed forward flight mode control. The low-speed mode control is as follows: the left and right tilt servos remain inactive, the tilt rotors remain vertically upward, the coaxial rotor system provides the main lift, and the tilt rotor system provides some lift; the flight controller generates anti-torque by adjusting the speed difference between the coaxial upper rotor and the coaxial lower rotor to achieve yaw control; it generates thrust difference by adjusting the speed difference between the left and right tilt rotors to achieve roll control; and it generates thrust difference by adjusting the speed difference between the coaxial rotor system and the tilt rotor system to achieve pitch control. The high-speed forward flight mode control: The flight controller sends commands to the left tilt servo and the right tilt servo, driving the servo arm to rotate the all-moving control surface assembly backward, which in turn drives the tilt motor and tilt rotor to tilt forward through the carbon fiber tilt shaft; at this time, the basic logic of the UAV's yaw control, roll control and pitch control is the same as in the low-speed mode, and the flight controller balances the additional yaw torque generated after the tilt rotor tilts by adjusting the speed difference of the coaxial dual propeller system.

[0013] Preferably, in high-speed forward flight mode, when the UAV rolls to the right, the flight controller increases the speed of the left tilt rotor and decreases the speed of the right tilt rotor to generate a rightward roll torque. At the same time, it adjusts the speed difference between the coaxial upper rotor and the coaxial lower rotor to generate a leftward counter-torque torque to counteract the additional rightward yaw torque brought by the tilt rotor.

[0014] Due to the adoption of the above-mentioned solution, the beneficial effects of this invention are as follows: Functional integration: Through the "coaxial dual propeller + tilt-rotor dual rotor" configuration and dual-mode control, vertical take-off and landing, hovering, and high-speed cruise functions are realized, meeting the needs of multiple military and civilian scenarios; The complex pitch control system of existing coaxial and tilt-rotor UAVs is eliminated, and attitude control is achieved through "rotor speed difference", reducing structural complexity and manufacturing difficulty, and improving reliability; The coaxial dual propeller system directly cancels the anti-torque torque through counter-rotation, and in high-speed forward flight mode, the coaxial dual propeller system balances the additional yaw torque, resulting in a smooth mode transition; The use of 3D printing (photosensitive resin parts) and composite materials (carbon fiber parts) balances structural strength and lightweight, and the manufacturing process is simple, reducing production costs. Attached Figure Description

[0015] Figure 1: Schematic diagram of the overall structure of the micro-sized semi-tilt UAV of the present invention. Figure 2: Schematic diagram of the structure of the present invention after removing the outer shell; Figure 3: Schematic diagram of the rear structure of the present invention; Figure 4: Side view schematic diagram of the high-speed forward flight mode of the present invention; Figure 5: Top view of the high-speed forward flight mode of the present invention.

[0016] Among them, 1. Coaxial upper rotor; 2. Coaxial lower rotor; 3. Coaxial motor; 4. Shell; 5. Landing gear; 6. Reinforced carbon rod; 7A. Left all-moving control surface; 7B. Right all-moving control surface; 8A. Left tilt motor; 8B. Right tilt motor; 9A. Left tilt rotor; 9B. Right tilt rotor; 10A. Left tilt servo; 10B. Right tilt servo; 11. Battery; 12. Bottom carbon plate; 13. Flight tower; 14. Middle carbon plate; 15. Front carbon tube fixing assembly; 16. Fuselage connecting carbon tube; 17. Rear carbon tube fixing assembly; 18. Rear carbon plate; 19. Tilting motor base; 20. Carbon fiber tilt shaft; 21. Bearing base; 22. Servo rocker arm. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] like Figure 1-5The image shows a micro-sized semi-tilt unmanned aerial vehicle (UAV), comprising a main structure, a coaxial dual-propeller system, a tilt-rotor system, all-moving control surface components, a flight control system, and a power supply component. The main structure includes an outer shell, landing gear, reinforcing carbon rods, a bottom carbon plate, a middle carbon plate, a rear carbon plate, a fuselage connecting carbon tube, a front carbon tube fixing component, and a rear carbon tube fixing component. The outer shell is made of photosensitive resin and is manufactured using 3D printing, wrapping the front of the fuselage to provide a flow-straightening and drag-reducing effect. The landing gear, reinforcing carbon rods, bottom carbon plate, middle carbon plate, and rear carbon plate are all made of carbon fiber. The bottom carbon plate is mounted on the landing gear, the middle carbon plate is located above the bottom carbon plate, and the rear carbon plate is located at the tail of the fuselage. The drone is equipped with three carbon fiber tubes. The front tubes are fixed to the middle carbon fiber plate via a front fixing component, and the rear tubes are fixed to the rear carbon fiber plate via a rear fixing component. Both the front and rear fixing components are made of photosensitive resin and are 3D printed. The coaxial dual-rotor system includes a coaxial upper rotor, a coaxial lower rotor, and a coaxial motor. The coaxial motor consists of two independently controlled brushless motors mounted on the middle carbon fiber plate. The coaxial upper rotor is located above the coaxial motor and rotates clockwise, while the coaxial lower rotor is located below the coaxial motor and rotates counterclockwise. The coaxial dual-rotor system provides the main lift for the drone and counteracts the rotor's anti-torque. The tilting dual-rotor system includes a left tilting motor and a right tilting motor. The system comprises a tilting motor, a left tilting rotor, a right tilting rotor, a left tilting servo, a right tilting servo, a tilting motor base, a carbon fiber tilting shaft, and a bearing base. The bearing base is mounted on the rear carbon plate and contains four ball bearings. The carbon fiber tilting shaft passes through the bearing base and is freely rotatable; its two sides are fixed to the all-moving control surface assembly at the center, and its two ends are fixed to the tilting motor base. The left and right tilting motors are mounted on the two side tilting motor bases and are both three-phase brushless motors. The left and right tilting rotors are connected to the output ends of the left and right tilting motors, respectively. The left and right tilting servos are mounted on the rear carbon plate, and their output ends are connected to servo rocker arms. The servo arm is connected to the all-moving control surface assembly via bolts to drive the carbon fiber tilt shaft, which in turn drives the tilt motor and tilt rotor. The all-moving control surface assembly includes a left all-moving control surface and a right all-moving control surface, both made of photosensitive resin and manufactured using 3D printing. It is positioned below the tilt rotor's wake to improve the tilt rotor's aerodynamic efficiency. The flight control system is integrated into the flight tower, which is mounted on the middle carbon plate via shock-absorbing studs. It includes a flight controller and an electronic speed controller for controlling the operation of the coaxial motor, left tilt motor, right tilt motor, left tilt servo, and right tilt servo. The power supply component is a 2200mAh lithium battery, fixed to the bottom carbon plate with nylon clips, which supplies power to the various electrical components of the UAV.

[0019] The maximum tilt angle of the tilt rotor driven by the left and right tilt servos is ≤60°.

[0020] The landing gear is manufactured using CNC cutting technology, and the bottom carbon plate, middle carbon plate, and rear carbon plate are all manufactured using CNC cutting technology.

[0021] The rotational speeds of the coaxial upper rotor and coaxial lower rotor are independently adjusted by the flight controller to achieve yaw control of the UAV.

[0022] The rotational speeds of the left and right tilt rotors are independently adjusted by the flight controller to achieve roll control of the UAV.

[0023] The speed difference between the coaxial dual-propeller system and the tilt-rotor system is adjusted by the flight controller to achieve pitch control of the UAV.

[0024] The control method for the micro-sized semi-tilt UAV includes two modes: low-speed mode control and high-speed forward flight mode control. The low-speed mode control is as follows: the left and right tilt servos remain inactive, the tilt rotors remain vertically upward, the coaxial rotor system provides the main lift, and the tilt rotor system provides some lift; the flight controller generates anti-torque by adjusting the speed difference between the coaxial upper rotor and the coaxial lower rotor to achieve yaw control; it generates thrust difference by adjusting the speed difference between the left and right tilt rotors to achieve roll control; and it generates thrust difference by adjusting the speed difference between the coaxial rotor system and the tilt rotor system to achieve pitch control. The high-speed forward flight mode control: The flight controller sends commands to the left tilt servo and the right tilt servo, driving the servo arm to rotate the all-moving control surface assembly backward, which in turn drives the tilt motor and tilt rotor to tilt forward through the carbon fiber tilt shaft; at this time, the basic logic of the UAV's yaw control, roll control and pitch control is the same as in the low-speed mode, and the flight controller balances the additional yaw torque generated after the tilt rotor tilts by adjusting the speed difference of the coaxial dual propeller system.

[0025] In high-speed forward flight mode, when the drone rolls to the right, the flight controller increases the speed of the left tilt rotor and decreases the speed of the right tilt rotor to generate a rightward roll torque. At the same time, it adjusts the speed difference between the coaxial upper rotor and the coaxial lower rotor to generate a leftward counter-torque torque to counteract the additional rightward yaw torque brought by the tilt rotor.

[0026] In high-speed forward flight mode, the left and right tilt motors simultaneously tilt the drone forward at a certain angle. The tilt angle can be controlled by the operator, but it must not exceed 60°. A diagram of the drone after tilting is shown below. Figure 4 , Figure 5 As shown.

[0027] The tilt mechanism operates as follows: The flight controller sends a command, causing the tilt servo to rotate the servo arm 22 backward. The servo arm 22 is bolted to the all-moving control surface, so the rotation of the servo arm 22 causes the all-moving control surface to tilt backward. The all-moving control surface is fixedly connected to the carbon fiber tilt shaft 20, thereby causing the tilt motor base 19, left tilt motor 8A, right tilt motor 8B, tilt rotor 9A, and tilt rotor 9B to tilt forward.

[0028] The drone's control principle at this time is as follows: the drone's gravity is still offset by the lift generated by the four rotors. In high-speed forward flight mode, the drone's yaw control is the same as in low-speed mode, based on the speed difference between coaxial rotor 1 and coaxial rotor 2, with the yaw torque generated by the rotor's anti-torque torque. In high-speed forward flight mode, the drone's roll control is the same as in low-speed mode, based on the speed difference between left tilt rotor 9A and right tilt rotor 9B, with the roll torque generated by the rotor's thrust. However, unlike low-speed mode, due to the tilt angle, the control at this time introduces an additional yaw torque, which needs to be balanced by the coaxial rotor system. For example, when the drone rolls to the right, increasing the speed of left tilt rotor 9A and decreasing the speed of right tilt rotor 9B causes the tilt rotors to generate a rightward roll torque, propelling the drone to roll to the right. At this point, the tilt rotor, having tilted forward at a certain angle, generates an additional yaw moment to the right. This needs to be balanced by the speed difference between coaxial rotor 1 and coaxial rotor 2, causing the coaxial rotor system to generate a yaw moment to the left. In high-speed forward flight mode, the drone's pitch control is the same as in low-speed mode, based on the speed difference between the coaxial rotor system and the tilt rotor system. The pitch moment is generated by the rotor thrust. For example, when the drone is nose-down, increasing the speed of the tilt rotor system and decreasing the speed of the coaxial rotor system causes the two rotor systems to generate a nose-down pitch moment, leading to the drone nose-down.

[0029] The above description of the embodiments is intended to enable those skilled in the art to understand and use the present invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art based on the principles of the present invention without departing from the scope of the invention should be within the protection scope of the present invention. The above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A micro-sized semi-tilt unmanned aerial vehicle, characterized in that, The application relates to a flight tower, which comprises a main body structure, a coaxial double-propeller system, a tilting double-rotor system, a full-motion rudder assembly, a flight control system and a power supply assembly; the main body structure comprises an outer shell, a landing gear, a reinforced carbon rod, a bottom carbon plate, a middle carbon plate, a rear carbon plate, a fuselage connecting carbon pipe, a carbon pipe front fixing assembly and a carbon pipe rear fixing assembly; the outer shell is made of photosensitive resin and is formed through 3D printing, and the outer shell wraps the front part of the main body to play a role of flow regulation and drag reduction; the landing gear, the reinforced carbon rod, the bottom carbon plate, the middle carbon plate and the rear carbon plate are all made of carbon fiber; the bottom carbon plate is installed on the landing gear, the middle carbon plate is located above the bottom carbon plate, and the rear carbon plate is located at the tail of the fuselage; the fuselage connecting carbon pipe is provided with three carbon pipes, the front part of the carbon pipe is fixed with the middle carbon plate through the carbon pipe front fixing assembly, and the rear part of the carbon pipe is fixed with the rear carbon plate through the carbon pipe rear fixing assembly; the carbon pipe front fixing assembly and the carbon pipe rear fixing assembly are both made of photosensitive resin and are formed through 3D printing; the coaxial double-propeller system comprises a coaxial upper rotor, a coaxial lower rotor and a coaxial motor; the coaxial motor is composed of two independently controlled brushless motors and is installed on the middle carbon plate; the coaxial upper rotor is arranged on the upper part of the coaxial motor and rotates clockwise, and the coaxial lower rotor is arranged on the lower part of the coaxial motor and rotates counterclockwise; the coaxial double-propeller system provides the main lifting force of the unmanned aerial vehicle and offsets the reverse torque of the rotor; the tilting double-rotor system comprises a left tilting motor, a right tilting motor, a left tilting rotor, a right tilting rotor, a left tilting servo, a right tilting servo, a tilting motor base, a carbon fiber tilting shaft and a bearing base; the bearing base is installed on the rear carbon plate and is internally provided with four ball bearings; the carbon fiber tilting shaft is arranged in the bearing base and can rotate freely; the middle parts of the two sides of the carbon fiber tilting shaft are fixed with the full-motion rudder assembly, and the two ends of the carbon fiber tilting shaft are respectively fixed with the tilting motor base; the left tilting motor and the right tilting motor are respectively installed on the two tilting motor bases and are all three-phase brushless motors; the left tilting rotor and the right tilting rotor are respectively connected with the output ends of the left tilting motor and the right tilting motor; the left tilting servo and the right tilting servo are installed on the rear carbon plate and are both connected with a servo arm at the output end; the servo arm is connected with the full-motion rudder assembly through a bolt to drive the carbon fiber tilting shaft to drive the tilting motor and the tilting rotor to tilt; the full-motion rudder assembly comprises a left full-motion rudder and a right full-motion rudder, both of which are made of photosensitive resin and are formed through 3D printing; the full-motion rudder assembly is arranged below the wake of the tilting rotor to improve the aerodynamic efficiency of the tilting rotor; the flight control system is integrated in the flight tower, the flight tower is installed on the middle carbon plate through damping studs, and the flight control system comprises a flight controller and an electronic speed regulator and is used for controlling the operation of the coaxial motor, the left tilting motor, the right tilting motor, the left tilting servo and the right tilting servo; the power supply assembly is a 2200mAh lithium battery which is fixed on the bottom carbon plate through a nylon buckle and is used for supplying power to the electric components of the unmanned aerial vehicle.

2. The micro small tilt-rotor drone according to claim 1, characterized in that, The maximum tilting angle of the left tilting servo and the right tilting servo driving the tilting rotor is less than or equal to 60 degrees.

3. The micro small tilt-rotor drone according to claim 1, wherein, The landing gear is made through a CNC cutting technology, and the bottom carbon plate, the middle carbon plate and the rear carbon plate are all made through the CNC cutting technology.

4. The micro small tilt-rotor drone according to claim 1, wherein, The rotation speed of the coaxial upper rotor and coaxial lower rotor is independently adjusted by the flight controller to realize the yaw control of the unmanned aerial vehicle.

5. The micro semi-tilt unmanned aerial vehicle according to claim 1, wherein, The rotation speed of the left tilt rotor and right tilt rotor is independently adjusted by the flight controller to realize the roll control of the unmanned aerial vehicle.

6. The micro small tilt-rotor drone according to claim 1, wherein, The rotation speed difference between the coaxial dual propeller system and the tilt dual rotor system is adjusted by the flight controller to realize the pitch control of the unmanned aerial vehicle.

7. A control method for the micro semi-tilt unmanned aerial vehicle according to any one of claims 1-6, characterized in that, Two modes are included: low speed mode control and high speed forward flight mode control. In the low speed mode control, the left tilt actuator and the right tilt actuator are not in action, the tilt rotor remains vertical upward, the coaxial dual propeller system provides main lift, and the tilt dual rotor system provides partial lift; the flight controller generates counter torque by adjusting the rotation speed difference between the coaxial upper rotor and the coaxial lower rotor to realize the yaw control of the unmanned aerial vehicle; the flight controller generates thrust difference by adjusting the rotation speed difference between the left tilt rotor and the right tilt rotor to realize the roll control of the unmanned aerial vehicle; the flight controller generates thrust difference by adjusting the rotation speed difference between the coaxial dual propeller system and the tilt dual rotor system to realize the pitch control of the unmanned aerial vehicle. In the high speed forward flight mode control, the flight controller sends instructions to the left tilt actuator and the right tilt actuator to drive the actuator rocker arm to rotate the full-actuated surface assembly backward, and then drive the tilt motor and the tilt rotor forward by the carbon fiber tilt shaft; at this time, the basic logic of the yaw control, the roll control and the pitch control of the unmanned aerial vehicle is consistent with that in the low speed mode, and the flight controller adjusts the rotation speed difference of the coaxial dual propeller system to balance the additional yaw moment generated by the tilt rotor after tilting.

8. The control method according to claim 7, characterized by, In the high speed forward flight mode, when the unmanned aerial vehicle rolls to the right, the flight controller increases the rotation speed of the left tilt rotor and reduces the rotation speed of the right tilt rotor to generate a right roll moment, and adjusts the rotation speed difference between the coaxial upper rotor and the coaxial lower rotor to generate a left counter torque to offset the additional right yaw moment caused by the tilt rotor.

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