CN109552611B

CN109552611B - Aircraft

Info

Publication number: CN109552611B
Application number: CN201811569840.4A
Authority: CN
Inventors: 胡华智
Original assignee: Ehang Intelligent Equipment Guangzhou Co Ltd
Current assignee: Ehang Intelligent Equipment Guangzhou Co Ltd
Priority date: 2017-01-20
Filing date: 2017-01-20
Publication date: 2021-03-16
Anticipated expiration: 2037-01-20
Also published as: WO2018133588A1; CN109552611A; CN106809382B; CN106809382A

Abstract

The invention discloses an aircraft, which comprises an aircraft main body, an arm component arranged on the aircraft main body and a power device fixed on the arm component, wherein the power device comprises a driving part and a propeller connected with the driving part; the aircraft is in a first state and a second state; the aircraft further comprises a sensor and a control unit; calculating an adjustment angle of the current pitch angle and a lift force provided by the propeller according to the pitch angle, the observation information and the target information; and controlling the aircraft to fly to a target position in front according to the lifting force provided by the propeller and the adjusting angle. The aircraft disclosed by the invention reduces the load of the propeller, and simultaneously reduces the power consumption of the motor so as to achieve longer endurance time of the aircraft under the same configuration of the battery and the power system.

Description

Aircraft

The application is a divisional application with the patent number of CN201710042794.1 and the application date of 2017.01.20, and the invention provides an aircraft and a control method thereof.

Technical Field

The invention relates to the technical field of aircrafts.

Background

Because the unmanned aerial vehicle aircraft has advantages such as the maneuverability is good, low cost, convenient to use, consequently, unmanned aerial vehicle aircraft has been applied to many trades, like in a plurality of fields such as taking photo by plane, agricultural plant protection, survey and drawing have obtained wide application.

In the process of implementing the invention, the inventor finds that the prior art has the following problems: the fixed wing plus propeller aircraft structure can lead the aircraft to generate the lift force of the fixed wing in the vertical direction in the process of flying ahead due to the influence of the fixed wing, and the existing propeller control method can not meet the flight control.

Disclosure of Invention

The invention mainly aims to provide an aircraft, aiming at overcoming the technical problems in the prior art.

In order to achieve the above object, an embodiment of the present invention provides an aircraft, where the aircraft includes an aircraft main body, a horn assembly disposed on the aircraft main body, a driving element fixed on the horn assembly, and a propeller connected to the driving element; the aircraft further comprises a sensor and a control unit;

the aircraft has two states, namely a first state and a second state, wherein the first state is a state when the aircraft flies forwards horizontally or is static on the bottom surface;

the second state is a state when the aircraft flies vertically upwards or hovers in the air, and in the second state, the rotating surface of the propeller is parallel to the horizontal plane, and the plane where the bottom surface of the aircraft is located has an inclination angle with the horizontal plane;

the sensor is used for detecting the current pitch angle and observation information of the aircraft, wherein the observation information is the current position and speed of the aircraft;

the control unit is used for acquiring target information, calculating an adjusting angle of a current pitch angle and lift force provided by a propeller of the aircraft according to the pitch angle, the observation information and the target information, and controlling the aircraft to fly to a target position according to the lift force and the adjusting angle provided by the propeller.

Further, the control unit comprises a first adjusting module, and the first adjusting module is used for adjusting the lift force of the propeller and adjusting the reference rotating speed of all driving pieces of the aircraft.

Further, the control unit comprises a second adjusting module, and the second adjusting module is used for adjusting the rotating speed of the corresponding driving element in all the driving elements of the aircraft.

Further, the horn assembly includes a first horn, a second horn, a third horn, and a fourth horn; and the second adjusting module is used for adjusting the rotating speeds of the driving parts of the first machine arm and the second machine arm according to the reference rotating speed adjusted by the first adjusting module.

Further, the horn assembly includes a first horn, a second horn, a third horn, and a fourth horn; and the second adjusting module is used for adjusting the rotating speeds of the driving pieces of the third and fourth machine arms according to the reference rotating speed adjusted by the first adjusting module.

Further, the aircraft moves upwards, the first adjusting module increases the rotating speeds of all the driving pieces, and the adjusting mode of the adjusting angle is that the second adjusting module increases the rotating speeds of the driving pieces of the first horn and the second horn, and decreases the rotating speeds of the driving pieces of the third horn and the fourth horn.

Further, the aircraft flies forwards, and the first adjusting module controls the rotating speed of the propeller to enable the aircraft to fly at a preset angle of the control unit.

Further, the aircraft moves downwards, the rotating speed of the driving piece is increased by the first adjusting module, and the adjusting mode of the adjusting angle is that the rotating speed of the first horn and the rotating speed of the second horn are reduced by the second adjusting module, and the rotating speed of the third horn and the rotating speed of the fourth horn are increased.

Further, the range of the adjustment angle is-10 to 10 °.

Further, the control unit is further configured to control the aircraft to fly at a preset pitch angle.

According to the aircraft and the control method thereof provided by the embodiment of the invention, on one hand, the dependence of the aircraft on the propeller can be reduced, so that the load of the propeller is reduced, and meanwhile, the power consumption of the motor is greatly reduced, so that the aircraft can have longer endurance under the same configuration of a battery and a power system; on the other hand, the control in the vertical direction is introduced, and the existing flight control method is perfected.

Drawings

FIG. 1 is a schematic representation of a forward state of an aircraft according to an embodiment of the invention;

FIG. 2 is a schematic structural diagram of an aircraft in accordance with an embodiment of the invention;

FIG. 3 is a top view of an aircraft according to an embodiment of the invention;

FIG. 4 is a side view of an aircraft of an embodiment of the present invention;

FIG. 5 is a front view of an aircraft according to an embodiment of the invention;

FIG. 6 is a rear view of an aircraft of an embodiment of the present invention;

FIG. 7 is a flowchart illustrating a control method of an aircraft according to a first embodiment of the invention entitled "an aircraft and a control method thereof" filed as 2017.01.20 at CN 201710042794.1;

fig. 8 is a schematic structural diagram of a sensor and control unit of an aircraft according to a second embodiment of the invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Implementation of various embodiments of the present invention will now be described with reference to the accompanying drawings. In the following description, suffixes such as "module", "component", or "unit" used to denote elements are used only for facilitating the explanation of the present invention, and have no specific meaning in themselves.

As shown in fig. 1 to 4, an aircraft includes an aircraft body 100, a horn assembly 200 disposed on the aircraft body 100 of the aircraft 10, and a power device 300 fixed on the horn assembly 200, wherein the power device 300 includes a driving member 320 and a propeller 340 connected to the driving member 320, one end of the aircraft body 100 is a nose 160, and the other end is a tail 170; the propeller 340 is arranged obliquely with respect to the aircraft body 100, wherein the propeller 340 is arranged obliquely in the direction of travel of the nose.

The arm assembly 200 provided on the aircraft body 100 includes four arms, each arm is provided with a driving member 320 and a propeller 340 fixed on the driving member 320, and the rotation surfaces of the four propellers 340 and the advancing direction of the aircraft body 100 are arranged in an inclined manner on the whole structure, the specific aircraft body 100 includes a nose 160, and the inclined direction of the four propellers 340 is inclined in a direction of the nose 160 of the aircraft body 100. Based on this, the area of the top surface of the aircraft body 100 is greater than the area of the bottom surface of the aircraft body 100, so that the aircraft body 100 is approximately in an arch structure, further, the length from the nose 160 to the top surface of the tail 170 is greater than the length from the nose 160 to the bottom surface of the tail 170, and the curvature of the top surface of the aircraft body 100 is greater than the curvature of the bottom surface, so that when the aircraft flies forward, the airflow generates a pressure difference on the upper and lower surfaces when passing through the aircraft body 100, thereby generating a climbing force, thereby lifting the aircraft body 100, thereby reducing the dependence on the propeller 340, reducing the load of the propeller 340, and greatly reducing the power consumption of the motor so as to achieve the purpose that the aircraft can have a longer endurance time under the same configuration of a battery and a power system. Preferably, the rotation planes of the four propellers 340 are all parallel to each other.

An air guiding portion 140 is protruded upward from the middle of the top surface of the aircraft body 100, and the air guiding portion 140 extends from the nose 160 to the tail 170. When the aircraft flies forwards, the aircraft body is parallel to the horizontal plane, and when airflow passes through the aircraft body 100, pressure difference is generated between the air guide part 140 and the bottom surface, so that climbing force is generated, the load of the propeller 340 can be reduced, more power is used for normal flight of the aircraft, and the aircraft has longer endurance time.

The horn assembly 200 is provided with a mounting base 220, the driving member 320 is arranged in the mounting base 220, the driving member 320 comprises a transmission member 322, and the propeller 340 is connected with the transmission member 322. The number of the mounting seats 220 corresponds to that of the horn, that is, each horn is provided with one mounting seat 220, the mounting seats 220 are specifically mounted at the tail end of the horn, and the mounting seats 220 are integrally formed with the horn, so that the horn has sufficient integral structural strength. In addition, the mounting seat 220 is a frame-shaped structure provided with a mounting cavity, the frame-shaped structure is preferably a cylinder, the driving member 320 is a motor, the motor is mounted in the mounting cavity, and then the propeller 340 is assembled, so that the assembly structure of the whole machine is more compact and stable, and the mounting and connecting manner is simple. In addition, the mounting base 220 is arranged at the tail end of the horn component 200, so that the moment generated by the motor can be effectively reduced, the weight of the tail end of the horn component 200 is reduced to the minimum, the weight of the whole machine is effectively reduced, and the flight time is prolonged. Of course, the mounting base 220 may be disposed at other positions on the horn assembly 200 according to the actual application. In another embodiment, the upper side and the lower side of the mounting seat 220 are provided with mounting cavities, the motors are fixed in the upper mounting cavity and the lower mounting cavity, and each motor is provided with one propeller, so that a single-mounting-seat double-propeller structure is formed, and the aircraft can obtain larger flight power and longer flight time.

As shown in fig. 4, when the aircraft is horizontally placed, the rotation plane of the propeller 340 has an inclination angle δ with respect to the horizontal plane, and δ is greater than 0 degree and smaller than 90 degrees. In practical use, according to different size and weight conditions of the aircraft, under the condition of not changing the battery capacity and the power of the driving member 320, through reliable theoretical calculation and simulation analysis, the value of the actual inclination angle delta of the rotating surface and the horizontal surface of the propeller 340 can be selected to be suitable within the range of the inclination angle delta, so that the auxiliary lift provided by the propeller 340 is sufficient, the load burden of the propeller 340 is reduced, and the short board with insufficient battery capacity and limited power of the driving member 320 can be obviously relieved. Of course, in other embodiments, the pitch angle δ of the propeller 340 may have other values, preferably an acute angle, and still be within the scope of the present invention.

Further, the inclination angle δ of the rotation plane of the propeller 340 to the horizontal plane is preferably 28.5 degrees. According to data obtained by theoretical calculation and simulation analysis, the conversion can be carried out, under the condition that the battery capacity and the motor power are fixed, when the inclination angle delta between the rotating surface of the propeller 340 and the horizontal plane is 28.5 degrees, the auxiliary lift force provided by the propeller 340 is the highest, and the degree of load reduction and dependence reduction on the propeller 340 is the most obvious, so that the aircraft has longer endurance under the condition of the same load.

As shown in fig. 2, 5 and 6, the arm assembly 200 includes a first arm 230, a second arm 240, a third arm 250 and a fourth arm 260, wherein the height of the end of the third arm 250 and the end of the fourth arm 260 are higher than the height of the end of the first arm 230 and the end of the second arm 240, the first arm 230 and the second arm 240 are disposed on the left and right sides of the aircraft body 100 in the nose direction, and the first arm 230 and the second arm 240 are respectively extended along the aircraft traveling direction, and the distance from the first arm 230 to the wind guiding portion 140 is equal to the distance from the second arm 240 to the wind guiding portion 140. The third horn 250 and the fourth horn 260 are disposed on the top surface of the aircraft body 100 in the tail direction, the third horn and the fourth horn extend in the vertical upward direction, and the distance from the third horn 250 to the wind guiding portion 140 is equal to the distance from the fourth horn 260 to the wind guiding portion 140. Through above-mentioned arrangement structure not only satisfy under the prerequisite of load requirement, can also make organism structure compacter, occupy littleer space, promote the flight performance of aircraft simultaneously.

The aircraft has two states, namely a first state and a second state, wherein the first state is a state when the aircraft flies forwards horizontally or is static on the bottom surface, in the first state, the rotating surface of the propeller 340 and the horizontal plane have an inclination angle delta, and the plane where the bottom surface of the aircraft body 100 is located is parallel to the horizontal plane; the inclination angle delta of the rotating surface of the propeller 340 to the horizontal plane is greater than 0 degree and smaller than 90 degrees, and preferably, the inclination angle delta of the rotating surface of the propeller 340 to the horizontal plane is 28.5 degrees. The rotation plane of the propeller 340 is inclined with respect to the horizontal plane, thereby generating a component force against the self-gravity of the aircraft, reducing the load of the propeller 340, increasing the flight time, and a component force in the horizontal direction, which is the traveling direction of the aircraft. The second state is a state when the aircraft flies vertically upward or hovers in the air, and in the second state, the rotation plane of the propeller 340 is parallel to the horizontal plane, and the plane on which the bottom surface of the aircraft is located has an inclination angle δ with respect to the horizontal plane.

Based on the above-mentioned aircraft, please refer to fig. 7, a first embodiment of the present invention provides a method for controlling an aircraft, which includes the steps of:

and S10, detecting the current pitch angle and observation information of the aircraft.

In this embodiment, the observation information is the current vertical position and velocity of the aircraft.

In one possible embodiment, this step may be preceded by the step of: and controlling the aircraft to fly at a preset pitch angle.

And S20, acquiring target information in the vertical direction.

And S30, calculating the adjusting angle of the current pitch angle and the lift force provided by the propeller of the aircraft according to the pitch angle, the observation information and the target information.

And S40, controlling the aircraft to fly to the target position in front according to the lift force and the adjusting angle provided by the propeller.

In this embodiment, controlling the aircraft to fly forward to the target position according to the lift force and the adjustment angle provided by the propeller comprises the following steps:

and adjusting the reference rotating speed of a driving piece connected with the propeller according to the lifting force provided by the propeller.

In this embodiment, controlling the aircraft to fly forward to the target position according to the lift force and the adjustment angle provided by the propeller further comprises the steps of:

and adjusting the rotating speed of a corresponding driving piece for controlling the pitching attitude of the aircraft, and adjusting the pitching angle of the aircraft according to the adjusting angle.

In this embodiment, the adjustment angle is in the range of-10 ° to 10 °.

As an example, the initial reference rotation speed value is V1, the adjusted reference rotation speed value is V2, and the rotation speed of the single motor is adjusted on the basis of the adjusted reference rotation speed value V2 to realize the pitch adjustment.

For a better understanding of the invention, the following is illustrated by way of example:

the included angle between the plane of the propeller and the plane of the wing is assumed to be theta, the whole aircraft has the mass of m, the gravity acceleration of g, the forward relative air speed of Va, the lift force borne by the wing is Fa, the lift force provided by the propeller is F, and the air resistance of the aircraft is F.

When the pitch angle is theta + delta theta (delta theta is assumed to range from-10 DEG to 10 DEG):

wing lift is a function of relative airspeed and pitch angle variation: fa is f (Va, Δ θ) (formula 1), where when Va is constant, smaller Δ θ is larger Fa, and larger Δ θ is smaller Fa, where Δ θ is the adjustment angle.

The aircraft air resistance is a function of the relative air velocity: f (va) (formula 2).

When the stress in the vertical direction is balanced: f ═ mg-Fa)/cos (θ ± Δ θ) (formula 3).

When the forward stress is balanced: f × sin (θ ± Δ θ) ═ F (equation 4).

As can be seen from the above, the variables that can be directly changed in the above 4 equations are Δ θ and F, so the motion control for the fly-ahead process can be realized by changing these two variables. Wherein the control priority is vertical motion control > pitch angle control > forward motion control.

Because the lift force F provided by the propeller has the minimum value and is not negative, under a certain condition, the pitch angle is at a certain angle, the lift force F provided by the propeller is the minimum, the forward vertical direction is stressed in balance, and the aircraft flies forward at a certain speed. At the moment, if the aircraft needs an upward force, only the lifting force F provided by the propeller needs to be improved; if the aircraft requires downward force when the lift force F provided by the propeller is minimal, Δ θ is increased to decrease Fa. Since the process is dynamically adjusted all the time during the flight, the changes of Δ θ and F will be output by the control unit, so that the control effect is optimized. The input of the control unit is the target and observation of the vertical motion, and the output is delta theta and F. Specifically, when the pitch angle of the aircraft is at a certain angle and the lift force F provided by the propeller is minimum, the forward vertical direction is stressed in balance, the aircraft flies forward at a certain speed, and at the moment, if the aircraft needs upward force, the lift force provided by the propeller is improved by improving the reference rotating speed of the propeller, so that the aircraft moves upwards; at the moment, if the aircraft needs downward force, the lift force applied to the wing is reduced by increasing the pitch angle of the aircraft, and then the aircraft moves downward. The target position is still reached when the lift provided by the propeller is reduced to a minimum, at which point the pitch angle needs to be increased to further move the aircraft downward. In other embodiments, the aircraft may also be controlled to move up or down by adjusting both the lift and pitch provided by the propellers.

When the lift force provided by the propeller is larger than the minimum value, the lift force provided by the propeller has increased and decreased space, and at the moment, if the aircraft needs upward force, the lift force provided by the propeller is increased by increasing the reference rotating speed of the propeller, so that the aircraft moves upwards; at the moment, if the aircraft needs downward force, the lifting force provided by the propeller is reduced by reducing the reference rotating speed of the propeller, so that the aircraft moves downwards. The target position is still reached when the lift provided by the propeller is reduced to a minimum, at which point the pitch angle needs to be increased to further move the aircraft downward.

Referring to fig. 8 in combination with fig. 1 to 6, an aircraft according to a second embodiment of the present invention includes an aircraft body, a horn assembly disposed on the aircraft body, and a power device fixed on the horn assembly, wherein the power device includes a driving member and a propeller connected to the driving member; the aircraft further comprises sensors 10 and a control unit 11;

the sensor 10 is used for detecting the current pitch angle and observation information of the aircraft, wherein the observation information is the current vertical position and speed of the aircraft; a control unit 11 for acquiring target information in a vertical direction; calculating the adjustment angle of the current pitch angle and the lift force provided by the propeller according to the pitch angle, the observation information and the target information; and controlling the aircraft to fly to the target position in front according to the lifting force and the adjusting angle provided by the propeller.

In a possible embodiment, the control unit 11 comprises a first adjustment module 111;

and a first adjusting module 111 for adjusting the reference rotation speed of all the driving members of the aircraft according to the lift force provided by the propeller.

In another possible embodiment, the control unit 11 further comprises a second adjustment module 112;

and a second adjusting module 112 for adjusting the rotation speed of the corresponding driving element of all the driving elements of the aircraft.

Specifically, the second adjusting module 112 may adjust the rotation speed of the driving members of the first and second booms; the rotational speed of the drive members of the third and fourth horn may also be adjusted. As an example, the rotational speed of the first and second horn may be decreased, the rotational speed of the third and fourth horn may be increased, and the pitch angle of the aircraft may be increased.

In this embodiment, the adjustment angle is in the range of-10 ° to 10 °. In a possible embodiment, the control unit 11 is also adapted to control the aircraft to fly at a preset pitch angle.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. The aircraft is characterized by comprising an aircraft body, a horn assembly arranged on the aircraft body, a driving piece fixed on the horn assembly, and a propeller connected with the driving piece; the aircraft further comprises a sensor and a control unit;

the sensor is used for detecting the current pitch angle and observation information of the aircraft, wherein the observation information is the current vertical position and speed of the aircraft;

the control unit is used for acquiring target information in the vertical direction, calculating an adjustment angle of a current pitch angle and lift force provided by a propeller of the aircraft according to the pitch angle, the observation information and the target information, and controlling the aircraft to fly to a target position according to the lift force and the adjustment angle provided by the propeller;

the horn component comprises a first horn, a second horn, a third horn and a fourth horn, the first horn and the second horn are arranged on the left side and the right side of the aircraft body in the direction of the nose of the aircraft, the first horn and the second horn are respectively arranged in an extending mode along the traveling direction of the aircraft, the third horn and the fourth horn are arranged on the top face of the aircraft body in the direction of the tail of the aircraft, and the third horn and the fourth horn are respectively arranged in an extending mode along the vertical upward direction;

the control unit comprises a first adjusting module, and the first adjusting module is used for adjusting the lift force of the propeller and adjusting the reference rotating speed of all driving pieces of the aircraft;

the control unit comprises a second adjusting module, and the second adjusting module is used for adjusting the rotating speed of a corresponding driving element in all driving elements of the aircraft;

if the aircraft moves upwards, the first adjusting module increases the rotating speeds of all driving pieces, and the adjusting mode of the adjusting angle is that the second adjusting module increases the rotating speeds of the driving pieces of the first arm and the second arm and decreases the rotating speeds of the driving pieces of the third arm and the fourth arm; if the aircraft moves downwards, the rotating speed of the driving piece is increased by the first adjusting module, and the adjusting mode of the adjusting angle is that the rotating speed of the first horn and the rotating speed of the second horn are reduced by the second adjusting module, and the rotating speed of the third horn and the rotating speed of the fourth horn are increased.

2. The aircraft of claim 1, wherein the aircraft is flying forward, and the first adjustment module controls the rotation speed of the propeller to enable the aircraft to fly at a preset angle of the control unit.

3. The aircraft of any one of claims 1 to 2, wherein the adjustment angle is in the range-10 ° to 10 °.

4. The aircraft of any one of claims 1-2, wherein the control unit is further configured to control the aircraft to fly at a predetermined pitch angle.