CN115384760A

CN115384760A - Unmanned aerial vehicle flight platform and unmanned aerial vehicle

Info

Publication number: CN115384760A
Application number: CN202210553352.4A
Authority: CN
Inventors: 王冠林; 曾富涔; 帅晶; 王飞; 张峰; 史海庆
Original assignee: Beijing Guanlin Weihang Technology Co ltd
Current assignee: Beijing Guanlin Weihang Technology Co ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2022-11-25

Abstract

The invention provides an unmanned aerial vehicle flight platform and an unmanned aerial vehicle. Unmanned aerial vehicle flight platform includes: the device comprises a plurality of cross beams, a plurality of longitudinal beams, a connecting piece, a plurality of rotors, a stress monitoring unit and a control unit. The transverse beams and the longitudinal beams are perpendicular to each other and form a grid-like structure, which is not fully symmetrical. The connecting piece connects the cross beam and the longitudinal beam at the intersection point. The plurality of rotors are distributed on the grid-shaped structure. The stress monitoring unit is arranged at a part of the intersection point and used for monitoring the stress data of the cross beam and the longitudinal beam at the intersection point in real time. The control unit is used for calculating a stress control amount for the rotor related to one or more of the cross beam and the longitudinal beam at the intersection point according to the stress data; and calculating a thrust control amount for each rotor based on the stress control amount and the flight control amount. The platform improves the stress distribution of the machine body, and has light weight and heavy load.

Description

Unmanned aerial vehicle flight platform and unmanned aerial vehicle

Technical Field

The invention relates to the technical field of unmanned aerial vehicles in general, in particular to an unmanned aerial vehicle flight platform and an unmanned aerial vehicle.

Background

Along with the gradual maturity of unmanned aerial vehicle technique, many rotor unmanned aerial vehicle are applied to the load transportation more and more. Conventional many rotor unmanned aerial vehicle is four rotor overall arrangement, and lift is limited. In order to increase the load carrying capacity of a multi-rotor unmanned aerial vehicle, the thrust-weight ratio of the unmanned aerial vehicle needs to be improved. The specific scheme comprises the steps of increasing the number of the rotors, increasing the thrust of the rotors, lightening the weight of the structure and the like.

To integrate more rotors, the rotors must be far from the fuselage to ensure that a safe distance is maintained between the rotors. However, the lengthening of the rotor arm increases the structural weight and reduces the rotor area ratio. Through a plurality of rotor arms that are the circumference array form and install on the fuselage, can increase plant protection unmanned aerial vehicle's load. But the planar utilization efficiency of the circumferential array is not the highest.

Patent document CN201922165467.2 discloses an eight-rotor unmanned aerial vehicle, which realizes the design scheme of eight rotors by four main arms and eight support arms. The cantilever system comprises four main arms connected with the body, two support arms extend outwards from the tail end of each main arm, and the motor with the propeller is supported by the tail end of each support arm. The two support arms extend outwards from the tail ends of the four main arms, so that the interval between the main arms is increased, and the number of the main arms is reduced.

In the case of an elongated horn, additional rotors may be mounted on the horn to increase the number of rotors. Patent document two 201620702115.X discloses a multi-rotor heavy-load plant protection unmanned aerial vehicle, which comprises a fuselage; the aircraft comprises a plurality of aircraft arms arranged on the periphery of an aircraft body, wherein the aircraft arms are arranged on the side wall of the aircraft body in a circumferential array manner, each aircraft arm comprises a supporting rod, a first rotor wing, a first brushless motor, a second rotor wing, a second brushless motor and a fixing frame, one end of the supporting rod is fixed on the side wall of the aircraft body, the first brushless motor is fixed in the middle of the supporting rod through the fixing frame, the first rotor wing is connected with an output shaft of the first brushless motor, the second brushless motor is fixed at the tail part of the supporting rod through the fixing frame, and the second rotor wing is arranged on the second brushless motor; a medicine storage tank arranged below the machine body; a drug spraying device mounted on the drug storage tank; and a landing gear mounted below the fuselage. Through a plurality of horn cooperations rotations that are circumference array form and install on the fuselage, the downward air current that produces of reinforcing increases plant protection unmanned aerial vehicle's load. In the solution disclosed in this patent document, single-layer rotors are distributed inside and outside, the rotors are in a circumferential planar array, the rotor area ratio is low, and all loads are transmitted to the central fuselage.

To reduce the weight of the horn structure, a coaxial rotor layout may be used. Every two rotors form a power unit, the washing speed under the rotors is improved in a relay mode, but the area of the coaxial double-rotor propeller is not increased relative to the area of the single rotor. The coaxial rotor does not increase the paddle area and therefore does not effectively improve rotor efficiency. Patent document three 201510782290.4 discloses a design scheme of heavy load unmanned aerial vehicle, including fuselage assembly and the horn assembly more than three, the one end of every horn assembly links to each other with the fuselage assembly, all is equipped with two coaxial rotor subassemblies of arranging on the other end of every horn assembly, and every rotor subassembly all includes a screw and a motor, and the bottom of fuselage assembly is equipped with the carry platform that is used for carrying article. The solution disclosed in this patent document uses double-deck coaxial multiple rotors and four arms, all the load being transferred to the fuselage.

In order to increase plant protection unmanned aerial vehicle's spray range, can adopt the overall arrangement of horizontal rotor. An eight-rotor unmanned aerial vehicle layout is formed by two parallel long arms and a plurality of short arms surrounding a vehicle body. The above design increases rotor utilization efficiency. Patent document four 201822177257.0 discloses a plant protection machine, which comprises a machine body, an undercarriage, a plurality of short arms and two long arms, wherein the short arms are arranged around the machine body, the two long arms are parallel to each other and are respectively arranged on the front side and the rear side of the machine body, one end of each short arm is fixedly connected with the machine body, and the other end of each short arm is provided with a first rotor assembly and is fixedly connected with the long arms; two ends of the long horn are respectively provided with a second rotor wing assembly, and the bottom of each rotor wing assembly is provided with a spraying device; the landing gear top support is connected to the long arm bottom. The integral strength of the machine body structure is ensured under the condition of enlarging the spray amplitude; compare with many rotor unmanned aerial vehicle of conventionality, the spray pattern is great under the equal load condition, and it is higher to spray efficiency, is favorable to saving plant protection activity duration and cost. However, in the technical solution disclosed in this patent document, the two parallel long arms are not directly connected, and the rigidity of the combined body is not effectively increased.

In order to improve the total lift force and the system reliability of the rotor unmanned aerial vehicle, patent document five 201611266600.8 discloses a matrix aircraft which is composed of a plurality of (two or more) basic multi-rotor aircrafts, the plurality of basic multi-rotor aircrafts form an m × n-order matrix, and m is greater than or equal to 1,n is greater than or equal to 1. By connecting a plurality of conventional multi-rotor aircrafts to form a matrix aircraft, higher load-carrying capacity is obtained on the basis of ensuring the flight quality; by adopting a plurality of GPS antennas and lengthening the antenna installation distance, higher position precision and heading precision are obtained, and the track precision and flight quality of the matrix aircraft during autonomous flight are improved; the multi-rotor aircraft can normally fly when one or more basic multi-rotor aircraft have faults, and batteries of the multi-rotor aircraft form a parallel system, so that the utilization efficiency of the batteries can be improved, and the multi-rotor aircraft has the battery fault redundancy capability. However, the plane combination of a plurality of many rotor crafts promotes the bearing capacity, but the mechanism is loose, and the utilization ratio is low, and payload is little, increases unmanned aerial vehicle's quantity simply not only can not reduce the oar dish load, has reduced structural efficiency moreover.

The common feature of the first to fourth patent documents is that a central structure is adopted, and all the arms are finally integrated into the fuselage. Because the rotor horn employed is a cantilever beam structure, the rotor horn needs sufficient strength to ensure structural stability. As the rotor diameter increases, the rotor arm length increases, further increasing the airframe strength requirements and structural weight. In addition, along with the increase of rotor diameter and horn length, the organism is kept away from to the rotor, and the proportion of rotor lifting surface in unmanned aerial vehicle whole projected area reduces, leads to hovering efficiency reduction. Above-mentioned patent document five links together a plurality of monomer unmanned aerial vehicle through the matrix structure, and every unmanned aerial vehicle's rotor still adopts the central type structure, need gather the lift of every unmanned aerial vehicle horn on the fuselage separately.

In the central structure category, the forces and moments of all rotors are summed at the central fuselage, thus requiring the fuselage to have sufficient structural strength. The increase of the number of the rotor wings leads to the increase of the structural weight, the increase of the number of the arms, the passive increase of the strength of the central airframe and the weight increase of the whole structure; by adopting the coaxial rotor wing scheme, the lower washing speed is increased, and the hovering efficiency is lower than that of a single-layer rotor wing, so that the hovering efficiency is not fully improved.

Disclosure of Invention

In order to solve at least one of the above problems in the prior art, an embodiment of the present invention provides an unmanned aerial vehicle flight platform, including: the device comprises a plurality of cross beams, a plurality of longitudinal beams, a connecting piece, a plurality of rotors, a stress monitoring unit and a control unit. The plurality of cross beams and the plurality of longitudinal beams are perpendicular to each other and form a grid-like structure, which is not fully symmetrical. The connecting pieces are arranged at the cross points of the plurality of cross beams and the plurality of longitudinal beams and are used for connecting the cross beams and the longitudinal beams at the cross points. The rotors are distributed on the grid-shaped structure. The stress monitoring unit is arranged at least part of the cross points of the cross beams and the longitudinal beams and is used for monitoring the stress data of the cross beams and the longitudinal beams at the cross points in real time. The control unit is used for: calculating a stress control quantity for a rotor associated with one or more of a cross-beam and a stringer at a cross-point from stress data monitored by the stress monitoring unit at the cross-point; and calculating a thrust control amount for each of the plurality of rotors based on the stress control amount and the flight control amount.

In some embodiments, the center points of the plurality of rotors are disposed at the end points and/or intersection points of the plurality of cross beams and the plurality of longitudinal beams, and the plurality of rotors are distributed axisymmetrically on the lattice structure.

In some embodiments, the stress control amount comprises a relative side stress control amount, wherein the relative side stress control amount is calculated from stress data monitored by a stress monitoring unit at the end of the spar where the rotor is located and a stress monitoring unit at the opposite end.

In some embodiments, the thrust control amount includes the flight control amount and the opposite side stress control amount for a side rotor of the plurality of rotors located at a side position of the lattice structure, wherein the flight control amount is calculated from a polar radius and a polar angle of the side rotor with respect to a center point of the drone flight platform and a flight control command.

In some embodiments, the stress control quantity comprises a cross-edge stress control quantity, wherein the cross-edge stress control quantity is calculated from stress data of the beams and the stringers at a cross-point where the rotor is approaching, as monitored by a stress monitoring unit at the cross-point.

In some embodiments, the thrust control quantity comprises the flight control quantity and the cross-edge stress control quantity for an inner rotor of the plurality of rotors located at an inner position of the lattice structure, wherein the flight control quantity is calculated from a polar radius and a polar angle of the inner rotor with respect to a center point of the drone flight platform and a flight control command.

In some embodiments, the drone flight platform further comprises a plurality of energy storage units mounted in a distributed manner on the lattice structure and each of the plurality of energy storage units is for powering an adjacent rotor.

In some embodiments, the unmanned aerial vehicle flight platform further comprises a plurality of load-bearing points disposed in a distributed manner on the lattice-like structure.

In some embodiments, the drone flight platform is switchable between a long side as the head direction and a short side as the head direction.

In a second aspect, embodiments of the present invention provide a drone comprising a drone flight platform according to any of the embodiments described above.

According to the unmanned aerial vehicle flight platform and the unmanned aerial vehicle comprising the unmanned aerial vehicle flight platform, the proportion of the rotor wing area in the projection area of the unmanned aerial vehicle is maximally improved through non-symmetrical layout; through the distributed fuselage structure, the structural strength requirement of the fuselage is reduced, and the structural weight of the fuselage is reduced; the stress distribution of the machine body is improved through distributed task loads, distributed energy storage units and distributed stress monitoring measures, and the weight of the machine body structure is further reduced; the machine head direction is flexibly set, so that the machine head is conveniently applied to the industrial fields of agricultural plant protection, logistics transportation and the like.

The embodiment of the invention adopts an asymmetric distributed stress monitoring multi-rotor unmanned aerial vehicle lift structure, and has the following technical effects:

(1) The structure weight is reduced: the number limit of the rotor wings and the arms of the multi-rotor unmanned aerial vehicle is broken through, and a conventional cantilever beam structure is changed into a simple beam structure, so that the structural strength is improved, the structural weight is reduced, and the larger load-carrying capacity is obtained;

(2) Efficiency of hovering has been promoted: the bottleneck of the number of arms of the existing centralized layout multi-rotor unmanned aerial vehicle is broken through, distributed lift force is formed, the number of rotors is effectively increased, the lift force area is increased, the load of a paddle disc is reduced, and the hovering efficiency is improved;

(3) The stress of the machine body is improved: the stress condition of the machine body is monitored and controlled in real time through intelligent monitoring, unnecessary structural weight is reduced, and hovering efficiency is further improved;

(4) The energy efficiency is improved: by adopting a distributed energy supply mode, the energy storage device is fully close to each rotor wing, the energy supply path is shortened, the loss and the weight of a line pipe are reduced, and the energy conversion efficiency is improved;

(5) The operation efficiency is improved: according to different application scenes, the flight mode with the largest span or the smallest resistance is flexibly selected, and the operation efficiency is improved.

The embodiment of the invention provides a general design scheme of a heavy-load unmanned aerial vehicle for load unmanned aerial vehicles, especially for logistics transportation and agricultural plant protection, can realize high efficiency and long-distance transportation of heavy loads, and can be applied to the technical fields of aerospace, unmanned aerial vehicles and the like.

Drawings

The above and other objects, features and advantages of embodiments of the present invention will become readily apparent from the following detailed description read in conjunction with the accompanying drawings. Several embodiments of the invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which:

fig. 1 shows a schematic diagram of an example of a 24-rotor drone flight platform according to an embodiment of the invention;

fig. 2 shows a schematic diagram of an example of an 18-rotor drone flying platform according to an embodiment of the invention;

figure 3 shows a schematic diagram of an example of a 12-rotor drone flight platform according to an embodiment of the invention;

fig. 4 shows a schematic flight direction diagram of a load-carrying drone according to an embodiment of the invention.

In the drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

Detailed Description

The principles and spirit of the present invention will be described with reference to a number of exemplary embodiments. It is understood that these embodiments are given solely for the purpose of enabling those skilled in the art to better understand and to practice the invention, and are not intended to limit the scope of the invention in any way.

In one aspect, embodiments of the present invention provide an unmanned aerial vehicle flight platform. Unmanned aerial vehicle flight platform includes: the device comprises a plurality of cross beams, a plurality of longitudinal beams, a connecting piece, a plurality of rotors, a stress monitoring unit and a control unit.

An unmanned aerial vehicle flight platform proposed by an embodiment of the present invention is exemplarily described below with reference to fig. 1, and fig. 1 shows a schematic view of an example of a 24-rotor unmanned aerial vehicle flight platform according to an embodiment of the present invention.

As shown in fig. 1, a plurality of cross members (111) (113) (115) (117) and a plurality of longitudinal members (112) (114) (116) (118) are perpendicular to each other and form a grid-like structure, and a connecting member is provided at an intersection of the plurality of cross members and the plurality of longitudinal members for connecting the cross members and the longitudinal members at the intersection. The cross beam, the longitudinal beam and the connecting piece form a body unit of the unmanned aerial vehicle flight platform. The cross beam and the longitudinal beam are connected with each other in a vertical mode through a connecting piece to form a net-shaped machine body structure. The plurality of rotors (121) (122) (123) (124) (125) (126) (127) (128) (131) (132) (133) (134) (135) (136) (137) (138) (141) (142) (143) (144) (145) (146) (147) (148) are distributed on the grid-shaped structure. As one embodiment of the present invention, as shown in fig. 1, the center points of the plurality of rotors are disposed at the end points and/or the intersection points of the plurality of cross members and the plurality of longitudinal members, and the plurality of rotors are axisymmetrically distributed on the lattice structure. Alternatively, the center point of the rotor may be located elsewhere on the cross member and the longitudinal member, as long as a distributed layout is achieved.

As an example, as shown in fig. 1, the end points of at least some of the plurality of cross beams and the plurality of longitudinal beams are not connected to the corresponding longitudinal beams and cross beams, in other words, the end points of at least some of the beams are not connected to the end points of other longitudinal beams and cross beams, nor to the middle sections of other longitudinal beams and cross beams.

The plurality of cross beams can be equal in length or unequal in length, and the plurality of longitudinal beams can also be equal in length or unequal in length. As an example, as shown in fig. 1, the beams (111), (117) and (113), (115) are different in length so that a line connecting center points of the rotors at the outer edges among the plurality of rotors has a dodecagon shape.

According to the layout shown in fig. 1, the arms of all rotors are not gathered at the center of the fuselage, but two or more rotors are in a group and are connected with each other in a manner that the arms are directly connected, so that the bearing routes between the rotors are not gathered at the center of the fuselage, the strength requirement at the center of the fuselage is reduced, and the weight of the fuselage structure is reduced.

The structure changes the conventional central centralized bearing mode into a network bearing mode, and forms distributed lift force through a reticular organism structure.

Optionally, the connecting piece can adopt modular structure, has the extension connection function, can make up unmanned aerial vehicle and form bigger distributed unmanned aerial vehicle platform each other, or obtain a plurality of small-size distributed unmanned aerial vehicle platforms through disassembling large-scale distributed unmanned aerial vehicle platform, realize the nimble combination or the decomposition of unmanned aerial vehicle fuselage to constitute the unmanned aerial vehicle flight platform of different rotor quantity.

As shown in fig. 1, the grid-like structure is not fully symmetric. Embodiments of the present invention differ from conventional fully symmetric central centralized fuselages in that: the length of the longitudinal fuselage is not equal to that of the transverse fuselage, and specifically, the length of the cross beam is not equal to that of the longitudinal beam, or the distances (128) - (125), (131) - (136), (132) - (135), (121) - (124) between the longitudinal rotors are not equal to the distances (127) - (122), (138) - (133), (137) - (134) and (126) - (123) between the transverse rotors, so that a non-symmetrical layout is presented, the non-lift area between the rotors is reduced, and the occupation ratio of the total area of the rotors in the projection area of the unmanned aerial vehicle is improved. By adding the inner rotors (141) (142) (143) (144) (145) (146) (147) (148) in the distributed fuselage frame, the occupation ratio of the total rotor area in the projection area of the unmanned aerial vehicle is further improved, and the hovering efficiency is further improved.

Stress monitoring units (151) (152) (153) (154) (161) (162) (163) (164) (165) (166) (167) (168) are arranged at least part of intersection points of the plurality of cross beams and the plurality of longitudinal beams. For example, the stress monitoring unit may be mounted on a portion of the connection member. The stress monitoring unit is used for monitoring the stress data of the cross beam and the longitudinal beam at the intersection point in real time, namely detecting the stress state of the cross beam and the longitudinal beam, for example, detecting the bending moment borne by the cross beam and the longitudinal beam. For example only, the stress monitoring unit may be a strain gauge, a piezo-resistor, a force gauge, or the like. The invention does not limit the specific type of the stress monitoring unit, as long as the stress monitoring unit has the function of stress detection.

The control unit (180) is configured to: calculating a stress control quantity for a rotor associated with one or more of the cross-over point, a cross-beam and a stringer at the cross-over point from the stress data monitored by the stress monitoring unit at the cross-over point; and calculating a thrust control amount for each of the plurality of rotors based on the stress control amount and the flight control amount. Namely, the control unit can adjust the lift force of the rotors in real time through the stress conditions of the cross beam and the longitudinal beam monitored by the stress monitoring unit in real time besides completing the conventional flight control function, and the stress state of the whole body structure is improved.

As an embodiment of the present invention, the rotor may be divided into a horn rotor, a side rotor, and an inner rotor. As shown in fig. 1, the rotary wings (121) (122) (123) (124) (125) (126) (127) (128) are located at the corner points of the grid-like structure of the drone for lift and flight control of the drone; the edge rotors (131) (132) (133) (134) (135) (136) (137) (138) are positioned at the side positions or edge positions of the grid-shaped structure of the unmanned aerial vehicle and are used for lift force, flight control and stress control of the outer edge beam of the unmanned aerial vehicle; the inner rotor (141) (142) (143) (144) (145) (146) (147) (148) is located inside the drone grid structure for lift, flight control and inner beam force control of the drone.

The control unit calculates the stress control quantity according to the real-time stress data, and attenuates or eliminates the bending moment on the connecting piece by adjusting the thrust of the inner rotor and the side rotor, thereby improving the stress state of the whole fuselage structure, reducing the structural strength requirement, further lightening the structural weight and avoiding the potential safety hazard caused by overlarge local stress. The control unit is also used for calculating flight control quantity. The stress control quantity and the flight control quantity are mixed to obtain the thrust control quantity, and the thrust control quantity is output to angle rotor, limit rotor and interior rotor, through real-time adjustment the lift of rotor realizes load unmanned aerial vehicle's stress control and flight control. In addition, through the differential lift of interior rotor, produce supplementary flight control moment, improve load unmanned aerial vehicle's flight control effect.

Big load unmanned aerial vehicle inevitably will produce the organism and warp when the bearing. In the prior art, in order to overcome the deformation, a mode of increasing the strength of the fuselage is generally adopted, but the weight of the fuselage structure is increased. The embodiment of the invention realizes a stress monitoring scheme through the functions of the stress monitoring unit and the control unit. A stress monitoring unit is arranged on a part of cross points of the cross beam and the longitudinal beam, and can measure the stress, such as bending moment, on the cross beam and the longitudinal beam in real time; the control unit calculates the stress control quantity according to the real-time stress data, and attenuates or eliminates the bending moment of the beam at the intersection point by adjusting the thrust of the rotor wing, so that the stress state of the whole fuselage structure is improved, the structural strength requirement is reduced, and the structural weight is further reduced. The control unit is also used for calculating flight control quantity. The stress control quantity and the flight control quantity are mixed to obtain the thrust control quantity, and each rotor wing is output, so that the stress control and the flight control of the load-carrying unmanned aerial vehicle are realized.

As an embodiment of the present invention, the thrust control amount u of any rotor i _i May include flight control quantities

Relative edge stress control

And cross edge stress control

Relative edge stress control

And calculating according to the stress data obtained by monitoring the stress monitoring unit at the end of the beam where the rotor wing is positioned and the stress monitoring unit at the opposite end. Cross edge stress control

And calculating according to the stress data of the cross beam and the longitudinal beam at the intersection point close to the rotor, which is monitored by the stress monitoring unit at the intersection point. As shown in the following formulas (1) and (2):

wherein the content of the first and second substances,

in the above equations (1) and (2), the flight control amount

For implementing flight control functions:

is the polar coordinate of the rotor i relative to the central point O of the grid structure of the unmanned aerial vehicle, d _i In order to be the polar radius of the film,

for rotor i with respect to the coordinate system x of the fuselage _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、 k _Az The flight control gains are roll, pitch, yaw and vertical control gains respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating to obtain rolling, pitching, yawing and vertical flight control instructions for the control unit;

in relation to the turning of rotor i, as shown in the following equation (3):

relative edge stress control

For attenuating or eliminating bending moments on opposite sides of the drone:

controlling gain for opposite side stress, M _i And M _j The stress data, such as bending moment values, measured for the stress monitoring units of the two opposite side rotors i and j.

Internal stress control amount

For attenuating or eliminating unmanned bodiesBending moment of the cross edge of the machine:

the gain is controlled for the cross-edge stress,

and

obtaining a coordinate system x along the machine body for the measurement of a stress monitoring unit j corresponding to the inner rotor i _b Axial direction and y _b Axial stress data, such as bending moment values.

Alternatively, for a rotary wing, including (121) (122) (123) (124) (125) (126) (127) (128), located at a corner point of the grid-like structure among the plurality of rotary wings, the thrust control amount may include only the flight control amount u _fcs ，

Therefore, u _pwr ＝u _fcs 。

As an embodiment of the invention, the side rotor comprises (131) (132) (133) (134) (135) (136) (137) (138), and the thrust control quantity can comprise a flight control quantity u _fcs And relative edge stress control

Thereby to obtain

Wherein, the flight control volume is calculated according to the polar radius and the polar angle of limit rotor relative to unmanned aerial vehicle flight platform's central point and flight control instruction.

As an embodiment of the invention, the thrust control amount may include a flight control amount u for an inner rotor including (141) (142) (143) (144) (145) (146) (147) (148) _fcs And cross edge stress control

Thereby to obtain

And calculating the flight control quantity according to the polar radius and polar angle of the inner rotor relative to the central point of the unmanned aerial vehicle flight platform and the flight control instruction.

The manner of calculating the flight control quantity will be described in detail below by taking the structure of the 24-rotor drone flight platform shown in fig. 1 as an example.

The thrust control amount is only a flight control amount for the rotary wings (121) (122) (123) (124) (125) (126) (127) (128), and the calculation method is as shown in the following equation (4).

Wherein u is _i Indicating the amount of thrust control, where i is the rotor number, d _i The polar radius of the horn rotor i relative to the drone grid center point O,

for the rotary wing i with respect to the coordinate system x of the fuselage _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

in connection with the turning of rotor i, the rotor turns clockwise to-1 and the rotor turns counter-clockwise to 1.

The thrust control amount may include a flight control amount and a relative side stress control amount for the side rotors (131) (132) (133) (134) (135) (136) (137) (138), and is calculated as shown in the following equation (5).

Wherein u is _i Indicating the amount of thrust control, where i is the rotor number, d _i The polar radius of the side rotor i relative to the grid-shaped central point O of the drone,

for side rotor i with respect to the body coordinate system x _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

in relation to the steering of the rotor i, the clockwise steering of the rotor is-1, and the anticlockwise steering of the rotor is 1;

controlling gain for opposite side stress, M _i And M _j Stress data, such as bending moment values, measured for stress monitoring units corresponding to the two opposite side rotors i and j.

The thrust control amount may include a flight control amount and a cross-edge stress control amount for the inner rotor (141) (142) (143) (144) (145) (146) (147) (148), and is calculated as shown in the following equation (6).

Wherein u is _i Indicating thrust control amountWherein i is the rotor mark, d _i The polar radius of the inner rotor i relative to the mesh centre point O of the drone,

is an inner rotor i relative to a body coordinate system x _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

related to the steering of the rotor i, the clockwise steering of the rotor is-1, and the anticlockwise steering of the rotor is 1;

the gain is controlled for the cross-edge stress,

and

It should be noted that the above embodiment is only one specific embodiment of the present invention, in which the rotors are divided into the angle rotor, the side rotor, and the inner rotor. In other embodiments, rotors may be classified according to other classification methods, depending on the particular layout of the beams, stringers, and rotors. As one example, the plurality of rotors may be divided into an outer rotor and an inner rotor. As another example, the plurality of rotors may be divided into an outer rotor, a middle rotor, an inner rotor, and so on. Under different division modes, the calculation mode of the flight control quantity of the rotor wing is adjusted correspondingly.

As an embodiment of the present invention, as shown in fig. 1, the flying platform of the unmanned aerial vehicle further includes a plurality of energy storage units (170) (or energy supply units) for storing energy required by the flying of the unmanned aerial vehicle. It is noted that for the sake of simplicity of the drawing, only three of the plurality of energy storage cells are labeled in fig. 1, and in fact, the dashed graphs having the same shape as the energy storage cells (170) shown in the drawing also all represent energy storage cells. The energy storage unit may be a battery, a fuel tank, a hydrogen tank, or the like. A plurality of energy storage units are distributively mounted on the fuselage frame lattice structure, for example, near the drone rotor units, each of the plurality of energy storage units for powering an adjacent rotor. The distributed installation of a plurality of energy storage units can relieve local stress load of the airframe.

It should be noted that the layout of the energy storage units shown in fig. 1 is only a specific example, and in practical applications, any suitable distributed layout may be adopted for the energy storage units according to the structure of the flight platform and the energy storage requirement.

According to the actual situation, the number or the capacity of the energy storage units can be increased or decreased appropriately. This distributed energy supply scheme arranges the energy storage unit dispersion on whole unmanned aerial vehicle fuselage frame, has shortened cable or oil circuit length between power supply unit and the rotor, has avoided having alleviateed the local load pressure of fuselage because of energy storage unit concentrates the local load pressure of carrying on the fuselage, has reduced fuselage rigidity demand and line loss, has further promoted structural efficiency and flight efficiency.

As an embodiment of the present invention, the unmanned aerial vehicle flight platform may further include a plurality of load-bearing points (not shown in fig. 1) distributed on the grid-like structure, for example, on at least a portion of the connectors. The load may be a mission load for performing a flight mission. The number of loads may be one or more. The load is mounted on the unmanned aerial vehicle fuselage in a multipoint distribution mode. The plurality of loads may be distributed over at least a portion of the connectors, or the entire load may be connected to at least a portion of the connectors in a multi-point distributed fashion. By dispersing the weight of the load on the whole fuselage frame, the local load pressure of the fuselage is reduced, the rigidity requirement and the weight of the fuselage are reduced, and the effective load is further improved.

Through the implementation mode, the machine body structure with the grid-shaped structure is utilized, and besides the distributed lift force, the distributed function and the distributed bearing are realized.

Referring to fig. 2, a schematic diagram of an example of an 18-rotor drone flying platform according to an embodiment of the present invention is shown. As shown in fig. 2, a plurality of cross members (211) (213) (215) and a plurality of longitudinal members (212) (214) (216) (218) are perpendicular to each other and form a grid-like structure, and a connecting member is provided at an intersection of the plurality of cross members and the plurality of longitudinal members for connecting the cross members and the longitudinal members at the intersection. The plurality of rotors (221) (222) (223) (224) (225) (226) (227) (228) (231) (232) (233) (234) (235) (236) (241) (242) (243) (244) are distributed on the grid-shaped structure.

Stress monitoring units (251) (252) (253) (254) (261) (262) (263) (264) are arranged at least part of the intersection points of the plurality of cross beams and the plurality of longitudinal beams. For example, the stress monitoring unit may be mounted on a portion of the connection member.

A control unit (280) for: calculating a stress control quantity for a rotor associated with one or more of the cross-over point, a cross-beam and a stringer at the cross-over point from the stress data monitored by the stress monitoring unit at the cross-over point; and calculating a thrust control amount for each of the plurality of rotors based on the stress control amount and the flight control amount.

As an embodiment of the present invention, the rotor may be divided into a horn rotor, a side rotor, and an inner rotor. As shown in fig. 2, the rotary wings (221) (222) (223) (224) (225) (226) (227) (228) are located at the corner points of the grid-like structure of the drone for lift and flight control of the drone; the edge rotors (231) (232) (233) (234) (235) (236) are positioned at the side positions or edge positions of the grid-shaped structure of the unmanned aerial vehicle and are used for lift force, flight control and stress control of the outer edge beam of the unmanned aerial vehicle; the inner rotor (241) (242) (243) (244) is located inside the grid structure of the drone for lift, flight control and internal beam force control of the drone.

The thrust control amount is only a flight control amount for the rotary wings (221) (222) (223) (224) (225) (226) (227) (228), and is calculated as shown in the following equation (7).

for the rotary wing i with respect to the coordinate system x of the fuselage _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. u _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

For the side rotors (231) (232) (233) (234) (235) (236), the thrust control amount may include a flight control amount and a relative side stress control amount, which are calculated as shown in the following equation (8).

for side rotor i with respect to the coordinate system x of the fuselage _b Polar angle in the axial direction, clockwisePositive; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. u _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

controlling gain for opposite side stress, M _i And M _j And stress data, such as bending moment values, measured for the stress monitoring units corresponding to the two opposite side rotors i and j.

The thrust control amount may include a flight control amount and a cross edge stress control amount for the inner rotor (241) (242) (243) (244), and is calculated as shown in the following equation (9).

Wherein u is _i Indicating the amount of thrust control, where i is the rotor number, d _i The polar radius of the inner rotor i relative to the mesh-like center point O of the drone,

the gain is controlled for the cross-edge stress,

and

As an embodiment of the present invention, as shown in fig. 2, the flying platform of the unmanned aerial vehicle further includes a plurality of energy storage units (270) (or energy supply units) for storing energy required by the flying of the unmanned aerial vehicle. It is noted that for the sake of simplicity of the drawing, only three of the plurality of energy storage cells are labeled in fig. 2, and in practice, the dashed graphs having the same shape as the energy storage cells (270) shown in the drawing also all represent energy storage cells. The energy storage unit may be a battery, a fuel tank, a hydrogen tank, or the like. A plurality of energy storage units are distributively mounted on the grid-like structure, e.g. near the drone rotor units, each of the plurality of energy storage units being for powering an adjacent rotor. The distributed installation of a plurality of energy storage units can relieve local stress load of the fuselage.

As an embodiment of the present invention, as shown in fig. 2, the unmanned aerial vehicle flying platform further includes a plurality of load bearing points, and the plurality of load bearing points are distributed on the grid-shaped structure. The load (290) may be mounted on a plurality of load bearing points. The load (290) may be a mission load for performing a flight mission. The number of loads (290) may be one or more. The load is mounted on the unmanned aerial vehicle fuselage in a multipoint distribution mode. The distribution positions of the loads (290) shown in fig. 2 may represent actual mounting positions of a plurality of loads, or may represent a plurality of connection points when one load is connected to a plurality of load bearing points in a multi-point distributed manner.

Through the implementation mode, the machine body structure with the grid-shaped structure is utilized, and on the basis of forming the distributed lift force, the distributed function and the distributed bearing are realized.

Referring to fig. 3, a schematic diagram of an example of a 12-rotor drone flying platform according to an embodiment of the invention is shown. As shown in fig. 3, a plurality of cross members (311) (313) and a plurality of longitudinal members (312) (314) (316) (318) are perpendicular to each other and form a lattice-like structure, and a connecting member is provided at an intersection of the plurality of cross members and the plurality of longitudinal members for connecting the cross members and the longitudinal members at the intersection. The plurality of rotors (321) (322) (323) (324) (325) (326) (327) (328) (331) (332) (333) (334) are distributed on the grid-shaped structure.

Stress monitoring units (351) (352) (353) (354) are arranged at least part of intersection points of the plurality of cross beams and the plurality of longitudinal beams. For example, the stress monitoring unit may be mounted on a portion of the connection member.

The control unit (380) is configured to: calculating a stress control quantity for a rotor associated with one or more of a cross-member and a stringer at a cross-point from stress data monitored by a stress monitoring unit at the cross-point; and calculating a thrust control amount for each of the plurality of rotors based on the stress control amount and the flight control amount.

As an embodiment of the present invention, the rotor may include a horn rotor and a side rotor. As shown in fig. 3, the rotary wings (321) (322) (323) (324) (325) (326) (327) (328) are located at the corner points of the drone grid for drone lift and flight control; the edge rotors (331) (332) (333) (334) are located at the side positions or edge positions of the grid-shaped structure of the unmanned aerial vehicle and are used for lift force, flight control and stress control of the outer edge beam of the unmanned aerial vehicle.

The thrust control amount is only a flight control amount for the rotary wings 321 (322) (323) (324) (325) (326) (327) (328), and the calculation method is as shown in the following equation (10).

for the rotary wing i with respect to the coordinate system x of the fuselage _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of formula _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

For the side rotors (331) (332) (333) (334), the thrust control amount may include a flight control amount and a relative side stress control amount, and is calculated as shown in the following equation (11).

for side rotor i with respect to the coordinate system x of the fuselage _b The polar angle in the axial direction is positive clockwise; d is the maximum polar radius of all rotors; k is a radical of _P 、k _Q 、k _R 、k _Az Roll, pitch, yaw and vertical control gains are respectively; u. of _P 、u _Q 、u _R 、u _Az Calculating roll, pitch, yaw and vertical flight control instructions for the control unit;

As an embodiment of the present invention, as shown in fig. 3, the drone flight platform further includes a plurality of energy storage units (371) (372) (373) (374) for storing energy required for the drone flight. The energy storage unit may be a battery, a fuel tank, a hydrogen tank, or the like. A plurality of energy storage units are distributively mounted on a grid-like structure, for example, near a drone rotor unit. Each of the plurality of energy storage units is for supplying power or oil to an adjacent rotor in close proximity, e.g., energy storage unit (371) is for supplying power to a nearby rotor (325) (326) (327) (328), and energy storage unit (372) is for supplying power to nearby rotors (331) and (334). The distributed installation of a plurality of energy storage units can relieve local stress load of the fuselage.

According to the actual situation, the number or the capacity of the energy storage units can be increased or decreased appropriately. According to the distributed energy supply scheme, the length of a cable or an oil way between the power supply unit and the rotor wing is shortened, the local load pressure of the aircraft body is reduced, the rigidity requirement and the line loss of the aircraft body are reduced, and the structural efficiency and the flight efficiency are further improved.

As an embodiment of the present invention, as shown in fig. 3, the unmanned aerial vehicle flight platform may further include a plurality of load bearing points, and the plurality of load bearing points are distributed on the grid-like structure, for example, may be disposed on at least a portion of the connecting members. The load (390) may be a mission load for performing a flight mission. The number of loads (390) may be one or more. The load (390) is mounted on the unmanned aerial vehicle fuselage in a multipoint distribution mode. The distribution positions of the loads (390) shown in fig. 3 may represent actual mounting positions of a plurality of loads, or may represent a plurality of connection points when one load is connected to a plurality of load bearing points in a multi-point distributed manner.

Referring to fig. 4, a schematic view of a flight direction of a heavy-duty drone according to an embodiment of the invention is shown. As an embodiment of the invention, the drone flight platform is switchable between a long side as the head direction and a short side as the head direction. Taking the application scene of the load-carrying unmanned aerial vehicle as an example, in the occasions needing large-span flight, such as agricultural plant protection, the load-carrying unmanned aerial vehicle takes the long edge as the direction of the machine head; under the occasion that needs long-range flight, like the commodity circulation transportation, load unmanned aerial vehicle uses the minor face as the aircraft nose direction. According to different application scenes or different flight stages, the load unmanned aerial vehicle can adjust the flight mode at any time.

In another aspect, embodiments of the invention provide a drone comprising a drone flight platform according to any of the embodiments described above.

According to the unmanned aerial vehicle flight platform and the unmanned aerial vehicle comprising the unmanned aerial vehicle flight platform, the proportion of the rotor wing area in the projection area of the unmanned aerial vehicle is maximally improved through non-symmetrical layout; through the distributed fuselage structure, the structural strength requirement of the fuselage is reduced, and the structural weight of the fuselage is reduced; the stress distribution of the airframe is improved through distributed task loads, distributed energy storage units and distributed stress monitoring measures, and the structural weight of the airframe is further reduced; the machine head direction is flexibly set, so that the machine head direction setting device is conveniently applied to the industry fields of agricultural plant protection, logistics transportation and the like.

The embodiment of the invention provides a general design scheme of a heavy-load unmanned aerial vehicle for load unmanned aerial vehicles, particularly for logistics transportation and agricultural plant protection, can realize high efficiency and long-distance transportation of heavy loads, and can be applied to the technical fields of aerospace, unmanned aerial vehicles and the like.

The invention has the main advantages of light weight, heavy load, flexible flight and convenient combination, and is particularly suitable for load-carrying unmanned aerial vehicles. However, the technical solution provided by the embodiment of the present invention is not only suitable for the load-carrying unmanned aerial vehicle, but also can be applied to any scene that needs to reduce the weight of the unmanned aerial vehicle.

The foregoing description of the embodiments of the invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. It will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. An unmanned aerial vehicle flight platform, its characterized in that, unmanned aerial vehicle flight platform includes: a plurality of crossbeams, a plurality of longitudinal beams, a connecting piece, a plurality of rotors, a stress monitoring unit and a control unit,

the plurality of cross beams and the plurality of longitudinal beams are perpendicular to each other and form a grid-like structure, the grid-like structure being non-fully symmetrical,

the connecting pieces are arranged at the cross points of the plurality of cross beams and the plurality of longitudinal beams and are used for connecting the cross beams and the longitudinal beams at the cross points,

the plurality of rotors are distributed on the grid-shaped structure;

the stress monitoring unit is arranged at least part of the cross points of the plurality of cross beams and the plurality of longitudinal beams and is used for monitoring the stress data of the cross beams and the longitudinal beams at the cross points in real time;

the control unit is used for: calculating a stress control quantity for a rotor associated with one or more of a cross-beam and a stringer at a cross-point from stress data monitored by the stress monitoring unit at the cross-point; and calculating a thrust control amount for each of the plurality of rotors based on the stress control amount and the flight control amount.

2. An unmanned aerial vehicle flight platform according to claim 1, wherein the centre points of the plurality of rotors are disposed at the end points and/or intersections of the plurality of cross beams and the plurality of stringers, and the plurality of rotors are distributed axisymmetrically on the lattice structure.

3. The unmanned aerial vehicle flight platform of claim 1, wherein the stress control quantities comprise relative side stress control quantities, wherein the relative side stress control quantities are calculated from stress data monitored by a stress monitoring unit at a home end of a spar on which the rotor is located and a stress monitoring unit at an opposite end.

4. An unmanned aerial vehicle flight platform according to claim 3, wherein the thrust control quantities comprise the flight control quantities and the opposing side stress control quantities for side rotors of the plurality of rotors located at side positions of the lattice structure, wherein the flight control quantities are calculated from a polar radius and a polar angle of the side rotors relative to a center point of the unmanned aerial vehicle flight platform and flight control instructions.

5. An unmanned aerial vehicle flight platform as claimed in claim 1, wherein the stress control quantities comprise cross-edge stress control quantities, wherein the cross-edge stress control quantities are calculated from stress data of the beams and stringers at a cross-point where the rotor is approaching, as monitored by a stress monitoring unit at that cross-point.

6. An unmanned aerial vehicle flight platform as claimed in claim 5, wherein the thrust control quantities comprise the flight control quantities and the cross-edge stress control quantities for an inner rotor of the plurality of rotors located at an interior position of the lattice structure, wherein the flight control quantities are calculated from a polar radius and a polar angle of the inner rotor relative to a center point of the unmanned aerial vehicle flight platform and flight control instructions.

7. An unmanned aerial vehicle flight platform as claimed in claim 1, further comprising a plurality of energy storage units distributively mounted on the lattice structure and each for energizing an adjacent rotor.

8. An unmanned aerial vehicle flight platform as claimed in claim 1, further comprising a plurality of load-bearing points disposed in a distributed manner on the lattice-like structure.

9. A drone flying platform according to claim 1, characterised in that it is switchable between a long side as the nose direction and a short side as the nose direction.

10. A drone, characterized in that it comprises a drone flight platform according to any one of claims 1 to 9.