1. The high-speed coaxial unmanned helicopter with the double tail thrusters is characterized by comprising a main body (1) and the tail thrusters, wherein the main body (1) is provided with coaxial double rotors (2) and adopts a course control system in a semi-differential control mode; the tail push device is arranged on two sides of the tail of the main body (1) and is symmetrically distributed; the tail push does not work under the hovering state of the unmanned helicopter, and gradually participates in work to provide thrust when the unmanned helicopter transits from a low-speed flight state to a high-speed flight state.

2. The double-tail-thrust-added high-speed coaxial unmanned helicopter according to claim 1, characterized in that the main fuselage (1) is streamlined.

3. The high-speed coaxial unmanned helicopter with added double tail thrusts according to claim 1 or 2, characterized in that the tail thrusts are double thrust propellers or double ducted tail rotors.

4. The high-speed coaxial unmanned helicopter with double tail propellers of claim 3, characterized in that the short tail (3) is symmetrically arranged on both sides of the tail of the main fuselage (1), the double propeller comprises two propellers (4), the propellers (4) consist of three blades (10), and the propellers (4) are rotatably connected with the short tail (3) through propeller supports (5) arranged in the middle of the three blades (10).

5. The double-tail-push-added high-speed coaxial unmanned helicopter according to claim 3, characterized in that the double ducted tail rotor comprises two ducted tail rotors (6), four ducted tail rotor blades (11) are arranged in the ducted tail rotor (6), and the ducted tail rotor (6) is directly connected with the tail side of the main fuselage (1).

6. The double-tail-thrust-added high-speed coaxial unmanned helicopter according to claim 1, wherein the heading control system comprises a lower rotor collective pitch and cyclic pitch control system, an upper rotor collective pitch and cyclic pitch control system; the total pitch and periodic pitch control system of the lower rotor is positioned on the lower rotor shaft, the total pitch and periodic pitch control system of the upper rotor is positioned on the upper rotor shaft, and the two systems are mutually independent.

Background

The current mainstream unmanned helicopter mainly comprises two forms of a single-rotor tail rotor and a coaxial double-rotor wing with conventional layout. The coaxial unmanned helicopter has excellent load-carrying performance and good stability, so that the coaxial unmanned helicopter is widely concerned. The coaxial unmanned helicopter can be divided into two types in the course control mode: one is a semi-differential operation mode, and the yaw of the helicopter is realized by controlling the total pitch of a pair of rotors; the other is a full differential operation mode, and the yaw of the helicopter is realized by controlling the total distance of two pairs of rotors.

The existing electric coaxial helicopters are provided with storage batteries, and energy sources in the storage batteries are used for flying of the coaxial helicopters. When the coaxial helicopter flies forward stably, the mutual interference between the two counter-rotating rotors generates additional induced loss, which leads to the increase of the consumed power of the rotors, and the rotors need to bear larger aerodynamic load when flying forward and need larger pitch angle to maintain stable forward flight. In addition, in a high-speed flight state, a main rotor of the coaxial unmanned helicopter needs a larger pitch angle to maintain stable forward flight and needs to bear larger pneumatic load, so that the power consumption of the main rotor is increased, and the flight speed and the flight quality are influenced.

For a coaxial helicopter, as the forward flight speed increases, the relative airflow velocity of the forward side rotor blades will increase and the relative airflow velocity of the aft side blades will decrease. Thus, relative to the blade, the total airflow direction is represented on the forward side as the sum of the forward incoming flow velocity and the tip velocity, and on the aft side as the difference between the forward incoming flow velocity and the tip velocity. Along with the increase of the asymmetry of the forward side and the backward side, the aerodynamic resistance and the vibration level can be obviously improved, and the speed of the unmanned helicopter is greatly influenced.

Therefore, how to improve the electric coaxial dual-rotor unmanned helicopter on the basis of the electric coaxial dual-rotor unmanned helicopter so as to adapt to high-speed flight is a problem to be solved by the technical personnel in the related field.

Disclosure of Invention

In view of the above, the invention provides a high-speed coaxial unmanned helicopter with double tail thrusters, which simplifies a control system of the coaxial unmanned helicopter, reduces the waste resistance of the helicopter, improves the high-speed flight capability of the coaxial unmanned helicopter, and improves the structural reliability of the helicopter, and the specific technical scheme is as follows:

a high-speed coaxial unmanned helicopter additionally provided with double tail thrusters comprises a main body and a tail thruster, wherein the main body is provided with coaxial double rotors and adopts a course control system in a semi-differential control mode; the tail push device is arranged on two sides of the tail of the main body and symmetrically distributed; the tail push does not work under the hovering state of the unmanned helicopter, and gradually participates in work to provide thrust when the unmanned helicopter transits from a low-speed flight state to a high-speed flight state.

In the process of gradually increasing thrust by the tail thruster, the pitch angle of the unmanned aerial vehicle is gradually increased, the attack angle of the rotor wing is also gradually increased, and forward flying tension generated by the rotor wing is gradually replaced by the horizontal thrust device. When the incidence angle of the rotor wing is changed into a positive incidence angle, the required power of the rotor wing is gradually reduced, the rotor wing gradually enters an autorotation state, the transition process is relatively stable, no complicated mechanical structure of tilting or stalling exists, the control difficulty is greatly reduced, and the transition flight risk is avoided.

Meanwhile, when the tail pushes away and provides thrust, the pitch angle of the unmanned helicopter in high-speed forward flight can be changed, so that the attitude of the unmanned helicopter is changed from head-down to head-up at a small angle, and the power required by the main rotor wing is reduced.

In addition, when the coaxial unmanned helicopter flies at a high speed, the course control effect of the semi-differential control system is weakened, and at the moment, the double-tail thrust can generate yaw torque by adjusting different thrust, so that the course control is compensated. Meanwhile, as the speed increases, the machine body also provides partial lift force, so that the pulling force of the main rotor of the coaxial unmanned helicopter is unloaded, and the power consumption of the main rotor is reduced. The helicopter can thus fly faster, also because the rotor's tension is relieved of its speed, thereby delaying the problem of the compressibility of the air flow on the rotor's forward side.

Therefore, the invention reduces the power consumption of the rotor wing and improves the flight speed of the coaxial double-rotor unmanned helicopter by improving the structure of the existing coaxial double-rotor helicopter and additionally arranging the double-tail push.

Preferably, the main body is streamlined.

Preferably, the tail propeller is a double-thrust propeller or a double-duct tail rotor.

Preferably, the afterbody bilateral symmetry of main fuselage is equipped with the short fin, two thrust propellers include two thrust propellers, thrust propeller comprises three blades, thrust propeller through being located three the screw support in the middle of the blade with the short fin rotates to be connected.

Preferably, the double-duct tail rotor comprises two duct tail rotors, four duct tail rotor blades are arranged in the duct tail rotor, and the duct tail rotor is directly connected with the side edge of the tail part of the main fuselage.

Preferably, the course control system comprises a lower rotor collective pitch and periodic variable pitch control system and an upper rotor collective pitch and periodic variable pitch control system; the total pitch and periodic pitch control system of the lower rotor is positioned on the lower rotor shaft, the total pitch and periodic pitch control system of the upper rotor is positioned on the upper rotor shaft, and the two systems are mutually independent.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a perspective view of a high speed coaxial unmanned helicopter incorporating dual thrust propellers according to the present invention;

FIG. 2 is a main view of the high speed coaxial unmanned helicopter with dual thrust propellers according to the present invention;

FIG. 3 is a top view of the high-speed coaxial unmanned helicopter with dual thrust propellers according to the present invention;

FIG. 4 is a side view of the high-speed coaxial unmanned helicopter with dual thrust propellers according to the present invention;

FIG. 5 is an isometric view of a high speed coaxial unmanned helicopter of the present invention with the addition of a dual ducted tail rotor;

FIG. 6 is a main view of the high-speed coaxial unmanned helicopter with the double ducted tail rotor according to the present invention;

FIG. 7 is a side view of the present invention of a high speed coaxial unmanned helicopter with the addition of a dual ducted tail rotor;

FIG. 8 is a top view of the high speed coaxial unmanned helicopter with the addition of a dual ducted tail rotor of the present invention;

FIG. 9 is a schematic view of the present invention with dual tail thrusters added for high speed coaxial unmanned helicopter maneuvering.

In the figure: 1-main fuselage, 2-coaxial dual rotors, 3-short empennage, 4-thrust propeller, 5-propeller support, 6-ducted tail rotor, 7-electric coaxial, 8-upper rotor, 9-lower rotor, 10-blade, 11-ducted tail rotor blade.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example (b):

as shown in fig. 1-9, the high-speed coaxial unmanned helicopter with double tail thrusters of the present invention comprises a main body 1 and a tail thruster, wherein the main body 1 is provided with coaxial double rotors 2 and adopts a semi-differential steering system; the tail push is arranged at the two sides of the tail part of the main body 1 and is symmetrically distributed; the tail push does not work under the hovering state of the unmanned helicopter, and when the unmanned helicopter transits from a low-speed state to a high-speed flight state, the tail push gradually participates in work to provide thrust.

In the process of gradually increasing thrust by the tail thruster, the pitch angle of the unmanned aerial vehicle is gradually increased, the attack angle of the rotor wing is also gradually increased, and forward flying tension generated by the rotor wing is gradually replaced by the horizontal thrust device. When the incidence angle of the rotor wing is changed into a positive incidence angle, the required power of the rotor wing is gradually reduced, the rotor wing gradually enters an autorotation state, the transition process is relatively stable, no complicated mechanical structure of tilting or stalling exists, the control difficulty is greatly reduced, and the transition flight risk is avoided. And when the tail pushes away and provides thrust, can change the high-speed preceding pitch angle of unmanned helicopter when flying, make unmanned aerial vehicle gesture become the small-angle and raise the head from the low head forward, the incoming flow blows in the tail from the rotor below and pushes away the oar dish, gets into similar rotation rotor state, provides partial lift, has reduced main rotor power demand.

Meanwhile, as the speed increases, the machine body also provides partial lift force, so that the pulling force of the main rotor of the coaxial unmanned helicopter is unloaded, and the power consumption of the main rotor is reduced. The helicopter can thus fly faster, also because the rotor's tension is relieved of its speed, thereby delaying the problem of the compressibility of the air flow on the rotor's forward side.

In addition, when the coaxial unmanned helicopter flies at a high speed, the course control effect of the semi-differential control system is weakened, and at the moment, the double-tail thrust can generate yaw torque by adjusting different thrust, so that the course control is compensated.

Further, this coaxial unmanned aerial vehicle's main fuselage 1 is streamlined, can effectively reduce the type and hinder when high-speed flight.

The tail pushing part of the high-speed coaxial unmanned helicopter additionally provided with the double-tail pushing comprises two schemes, namely additionally arranging a double-thrust propeller at the tail part of a main body 1 to perform tail pushing and additionally arranging a double-duct tail rotor at the tail part of the main body 1 to perform tail pushing respectively.

In particular, the method comprises the following steps of,

as shown in fig. 1-4, when a double-thrust propeller is used for tail pushing, short tail fins 3 are symmetrically arranged on two sides of the tail of a main body 1, the double-thrust propeller comprises two thrust propellers 4, the thrust propellers 4 are composed of three blades 10, and the thrust propellers 4 are rotatably connected with the short tail fins 3 through propeller supports 5 positioned in the middle of the three blades 10.

As shown in fig. 5-8, when the dual-duct tail rotor is used as a tail pusher, the dual-duct tail rotor includes two duct tail rotors 6, four duct tail rotor blades 11 are arranged in the duct tail rotor 6, and the duct tail rotor 6 is directly connected with the tail side of the main fuselage 1.

The thrust propeller 4 or the ducted tail rotor 6 does not work in a hovering state, and when the coaxial helicopter is in a transition state from a low-speed flight state to a high-speed flight state, the thrust propeller 4 or the ducted tail rotor 6 gradually participates in work. The thrust propeller 4 or the ducted tail rotor 6 can provide forward flight speed for the coaxial helicopter, so that when the thrust propeller 4 or the ducted tail rotor 6 participates in flying, the pitch angle of the unmanned helicopter is changed, the attitude of the unmanned helicopter is changed from head-down to head-up at a small angle, and the power required by the main rotor wing is greatly reduced. During high-speed flight, the course control effect of the semi-differential control system is weakened, and at the moment, the double-thrust propeller or the double-duct tail rotor generates yaw torque by adjusting different thrust, so that course control is compensated.

The tension of the main rotor of the coaxial unmanned helicopter is unloaded, so that the power consumption of the main rotor is reduced, the power of the main rotor is saved, the coaxial helicopter can fly at a smaller pitch angle, the type resistance is reduced, and the cruising speed of the coaxial helicopter is improved.

Thereby the pulling force of rotor obtains the rotational speed that the uninstallation made the rotor and can reduce, and then alleviates the air current compression problem of rotor antegrade side, and air resistance power and vibration level will all effectively reduce, therefore the helicopter can fly sooner.

Furthermore, the ducted tail rotor 6 of the present invention is safer than the thrust propeller 4.

As shown in FIG. 9, the course control system includes a lower rotor collective pitch and cyclic pitch control system, an upper rotor collective pitch and cyclic pitch control system; the total pitch and periodic pitch control system of the lower rotor is positioned on the lower rotor shaft, the total pitch and periodic pitch control system of the upper rotor is positioned on the upper rotor shaft, and the two systems are mutually independent.

In the invention, a high-speed coaxial unmanned helicopter additionally provided with double tail thrusters belongs to an electric unmanned aerial vehicle, a course control system of the high-speed coaxial unmanned helicopter belongs to a semi-differential control mode, and the principle of the control system is as follows: the course control steering engine is connected with the upper rotor variable-pitch rocker arm through a transmission mechanism, and transmits a course control signal to realize the pitch change of the upper rotor 8; the longitudinal and transverse steering engine is connected with the inclinator through a transmission mechanism, so that periodic pitch change is realized, and the longitudinal and transverse postures of the unmanned helicopter are changed. The detailed structure is disclosed in the patent number 201510741452.X, which is named as a coaxial unmanned helicopter control system of upper rotor semi-differential course control, and the description is not repeated.

Certainly, the semi-differential course control system in the invention can also connect the course control steering engine with the lower rotor wing variable-pitch rocker arm through the transmission mechanism to transmit the course control signal and realize the pitch change of the lower rotor wing 9; the longitudinal and transverse steering engine is connected with the inclinator through a transmission mechanism, so that periodic pitch change is realized, and the longitudinal and transverse postures of the unmanned helicopter are changed. The upper rotor 8 and the lower rotor 9 are connected by an electric common shaft 7.

The coaxial unmanned helicopter adopts the layout of the coaxial dual rotors 2, the tail thrusters are positioned at the tail part of the unmanned helicopter and are symmetrical left and right, the overall layout is reasonable, and the operation is convenient.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.