Multi-rotor unmanned aerial vehicle

Abstract

FIELD: aviation.SUBSTANCE: multi-rotor unmanned aerial vehicle includes a central part with a cargo platform, power support beams connected to it, on which rotors are mounted, and support legs. The power support beams are designed in the form of a power support ring, on which rotors with twin coaxial counter-rotating propellers, installed in a common annular fairing, are located uniformly along its length and azimuth with a given pitch. The axes of rotation of the screws are oriented along the normal to the plane of the power support ring that connects them. The cargo platform is made connected to the power support ring by means of power plates fixed to it, located in the plane of the power support ring in the spaces between the rotors and oriented radially, or by means of spokes or power threads operating in tension.EFFECT: simplified design, reduced weight and increased carrying capacity of the multi-rotor UAV.3 cl, 12 dwg

Description

[0001] The invention relates to the field of design of unmanned aerial vehicles (UAVs) – drones.

[0002] The use and application of UAVs in civilian life is constantly growing. They are used for security, video and filming, crop dusting, mail and parcel delivery, delivering medical equipment and medications, fire extinguishers to emergency scenes, and more. Military applications of UAVs have also become common and widespread: for reconnaissance, air pollution and radioactivity assessment, wounded evacuation, bombing and missile strikes, and ammunition delivery.

[0003] The most common UAVs are so-called multirotor (multi-rotor) UAVs. They are flying platforms with multiple electric brushless motors and propellers (rotors). Fig. 1 shows a drone with four rotors (a quadcopter), Fig. 2 shows a drone with six rotors (a hexacopter), and Fig. 3 shows a drone with eight rotors (an octocopter).

[0004] These UAVs can be considered analogs of the proposed invention. Their well-known advantages include the ability to take off vertically and hover above an object. They also maintain a horizontal position relative to the ground and can move left, right, forward, backward, up and down, as well as rotate around their axes. These actions are accomplished by varying the thrust on each electric motor.

[0005] Of all types of drones, multirotor UAVs are relatively the simplest to manufacture, control, and relatively cheap (https: / / aviatest.aero / articles / tipy-bespilotnykh-letatelnykh-apparatov-obzor / ; http: / / www.tzmagazine.ru / jpage.php?uid1=1348&uid2=1474&uid3=1479; https: / / aeromotus.ru / drony-s-nepodvizhnym-krylom-ili-multikopter-chto-vybrat-dlya-aerosemki-2 / ; https: / / militaryarms.ru / vertolety / bpla / ; https: / / art-assorty.ru / 54215-gibridnye-kvadrokoptery-chto-eto.html).

[0006] One of the main disadvantages of such drones is their limited load capacity.

[0007] It is known that the payload capacity of such UAVs can be somewhat increased by using so-called coaxial dual rotors—twin coaxial propellers driven by electric motors. For example, the DJI "Agras T 40" multi-rotor UAV shown in Fig. 4 is equipped with such rotors, increasing the UAV's payload capacity by 30%.

[0008] It is also known that it is possible to increase the efficiency of twin coaxial propellers driven by electric motors (Fig. 5) by installing them in a common ring (https: / / Hi.news.ru. Technology. Drone – V – video– Kolca – mozhet).

[0009] Fig. 6 and 7 schematically show the classification of types of multi-rotor UAVs according to the shape of the support beams, the number of rotors and the presence of coaxial propellers: tricopter, quadcopter, hexacopter, and there is no diagram similar to the proposed design.

[0010] The closest to the proposed invention and adopted as its prototype is the DJI "Agras MG-1P" octocopter UAV (https: / / www.aspector.ru / product / multikopter-dji-agras-mg-1p-dlya / ) with eight propellers, each of which is rotated by its own electric motor (eight rotors), located on the periphery of the UAV remote from the central cargo platform using a system of power support beams (Fig. 8). The octocopter is also equipped with support legs that ensure a predetermined position of the UAV when parked.

[0011] This UAV is highly stable and powerful, capable of carrying a relatively large payload and resisting winds more effectively. However, the increased number of rotors (although practically no more than eight) complicates its design, and the combined length and weight of the 12 beams supporting the outboard rotors are excessively large. Another drawback of known multi-rotor UAVs is that the relatively small cargo space in their central section hinders their use for transporting bulky, low-density cargo, such as agricultural spray chemicals. Transporting heavy loads is also challenging due to strength issues and the excessive weight of the extended beam network.

[0012] The purpose of the proposed invention is to increase the competitiveness of a multi-rotor unmanned aerial vehicle.

[0013] The technical result of the proposed invention consists in simplifying the design of a multi-rotor UAV, reducing the weight of the design and increasing the carrying capacity of the multi-rotor UAV.

[0014] The technical result is achieved by a multi-rotor unmanned aerial vehicle comprising a central section with a cargo platform and associated load-bearing support beams on which rotors and support legs are mounted. The load-bearing support beams are designed as a load-bearing support ring on which rotors with twin coaxial, counter-rotating propellers mounted within a common annular fairing are uniformly spaced along its length and azimuth at a specified pitch. The propeller axes of rotation are oriented normal to the plane of the connecting load-bearing support ring. The cargo platform is connected to the load-bearing support ring via load-bearing plates secured to it and located in the plane of the load-bearing support ring in the spaces between the rotors and oriented radially. Alternatively, the cargo platform is connected to the load-bearing support ring via tension spokes or load-bearing threads.The force plates are additionally equipped with devices for fastening small-sized distributed loads outside and inside the space of the support ring; support posts oriented normally to the plane of the force support ring are also connected to the force support ring.

[0015] The technical result is also achieved by the fact that in a multi-rotor unmanned aerial vehicle, the cargo platform is made in the form of a mesh connected to a power support ring using tension spokes or power threads.

[0016] The technical result is also achieved by the fact that in a multi-rotor unmanned aerial vehicle the total number of rotors does not exceed 20.

[0017] The proposed invention is illustrated by the following figures.

[0018] Fig. 1 – DJI “Mavic Pro Platinum” quadcopter,

[0019] fig. 2 – hexacopter “Yuneec Typhoon H. Professional”,

[0020] Fig. 3 – octocopter, the rotors of which have one screw,

[0021] Fig. 4 – quadcopter with coaxial propellers DJI “Agras T40”,

[0022] Fig. 5 – coaxial rotor with screws and a ring common to them,

[0023] Fig. 6 – diagrams of the main types of support beams for multirotor UAVs,

[0024] Fig. 7 – diagrams of the main types of multirotor UAVs,

[0025] fig. 8 – DJI “Agras MG-1P” octopter,

[0026] Fig. 9 – plan view of the proposed apparatus with a cargo platform in its center,

[0027] Fig. 10 – section view A-A of Fig. 9,

[0028] Fig. 11 – plan view of the proposed apparatus with a cargo net in its center, secured to a system of threads or rods,

[0029] Fig. 12 – section B-B of Fig. 11.

[0030] The positions in Fig. 9-12 are as follows:

[0031] 1 – annular coaxial rotors (electric motors with screws in a common ring connecting them),

[0032] 2 – cargo platform,

[0033] 3 – power support ring,

[0034] 4 – fasteners for distributed payloads on force plates,

[0035] 5 – coaxial propellers in an annular fairing,

[0036] 6 – radially oriented force plates,

[0037] 7 – take-off and landing support legs,

[0038] 8 – cargo net,

[0039] 9 – knitting needles or power threads.

[0040] The proposed multi-rotor unmanned aerial vehicle is designed and operates as follows.

[0041] The multi-rotor UAV's power support beams are combined into a single closed-loop support beam in the form of a power support ring 3 (see Figs. 9-12). Annular coaxial rotors 1—up to approximately 20 in total—are uniformly spaced along the ring's length and azimuth at a specified pitch. To improve the rotors' efficiency, each rotor consists of at least two coaxial counter-rotating propellers 5 mounted in a common annular fairing and driven by its own electric motor (not shown in the figures). The axes of rotation of the rotors 1 are oriented normal to the plane of the power support ring that connects them. The specified pitch of the rotors is determined by the diameter of the power support ring and the number of rotors.

[0042] The platform for placing cargo in the central part of the multi-rotor UAV can be made in the form of a cargo platform 2, located inside the support force ring 3 and rigidly connected to it with the help of force plates 6 fixed to it, located in the plane of the support force ring in the gaps between the rotors 1, distributed evenly along the azimuth and oriented radially (see Fig. 9, 10).

[0043] The cargo platform 2 in the central part of the multi-rotor UAV can be replaced with a removable net 8. In this case, the net 8 is not connected to the force plates 6, but is attached to a system of spokes or force threads 9 operating in tension, located inside the support force ring 3 (see Figs. 11, 12). In this case, each force thread 9 (or each rod 9) passes through the center of the ring 3 and is fixed at two diametrically opposite points of the support force ring 3 between the force plates 6 and the rotors 1. The number of threads 9 (rods 9) is equal to twice the number of rotors. All threads 9 (rods 9) together form a structure capable of holding the removable net 8 with a load. The multi-rotor UAV with a system of spokes and rods can also be used without the net 8.

[0044] The cargo platform 2 in the central part of the multi-rotor UAV can also be attached to the supporting power ring 3 not by means of the power plates 6, but by means of the above-described system of tension spokes or power threads (this option is not shown in the figures).

[0045] In addition, to increase the carrying capacity of the proposed UAV, the force plates 6 are equipped with devices for fastening small-sized distributed payloads 4 outside and inside the space of the ring.

[0046] Due to the small distance between the point of application of the lifting force of the rotors 1 and the point of application of the gravity force of the payloads 4 located between the rotors 1, the bending moments acting on the sections of the support ring 3 are reduced to a minimum. And due to the presence of the payload 4 on the plate 6 outside the space of the ring, the torque acting on the sections of the support ring 3 is reduced to a minimum. This causes an increase in the weight return of the power ring 3.

[0047] To ensure takeoff and landing of the UAV, support legs 7 are installed at the front and rear of the UAV, as well as on its sides. Legs 7 are oriented normal to the plane of the power support ring 3.

[0048] Thus, by replacing a large number of branched networks of straight power support beams with one single, relatively less extended and light - a curved beam - in the form of a power support ring, on which annular coaxial rotors (up to about twenty in number) are evenly located along its length and azimuth, the axes of which are oriented along the normal to the plane of the power support ring, a simplification of the design is achieved.

[0049] The proposed multi-rotor UAV design also enables an expanded range and increased payload capacity. Firstly, these are large, relatively low-density payloads positioned on a cargo platform (or grid) located within the load-bearing support ring and connected to it by uniformly distributed azimuthally and radially oriented load plates (or spokes, load threads). Secondly, these are small, distributed payloads positioned on the same load plates secured to the load-bearing support ring, both inside and outside the ring. The UAV's increased payload capacity is also achieved through the use of a large number (up to approximately 20) of annular rotors constructed in a coaxial configuration, consisting of at least two coaxial, counter-rotating propellers located within a common ring.

[0050] The feasibility of the proposed closed-loop design UAV, in particular, the possibility of achieving in such designs a significant reduction in the weight of their power structure, its simplification, and an increase in the efficiency of solving problems of dynamics and resource, are confirmed by the accumulated experience in creating such designs.

Claims

1. A multi-rotor unmanned aerial vehicle comprising a central portion with a cargo platform, power support beams connected thereto on which rotors are mounted, and support legs, characterized in that the power support beams are made in the form of a power support ring on which rotors with twin coaxial counter-rotating propellers mounted in a common annular fairing are arranged uniformly along its length and azimuth with a given pitch, the axes of rotation of the propellers being oriented normal to the plane of the power support ring uniting them, the cargo platform is made connected to the power support ring by means of power plates secured thereto, located in the plane of the power support ring in the spaces between the rotors and oriented radially, or by means of spokes or power threads operating in tension, the power plates are additionally provided with devices for fastening small-sized distributed loads outside and inside the space of the ring,The support pillars, oriented normally to the plane of the support ring, are also connected to the power support ring.

2. A multi-rotor unmanned aerial vehicle according to paragraph 1, characterized in that the cargo platform is made in the form of a mesh in the case where the cargo platform is connected to the power support ring using tension spokes or power threads.

3. A multi-rotor unmanned aerial vehicle according to paragraph 1, characterized in that the total number of rotors does not exceed 20.

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